ondas
... Read more
Less

Article

Pereira, Amarildo A. ; Neves, Athos C.; Ladeira, Débora; Caprace, Jean-David (2024) Marine Structures 97: 103652.
Corrosion is considered an important aspect in assessing the integrity of offshore marine structures. It is a process that involves the risk of keeping floating production storage and offloading (FPSO) tanks out of operation for a long time, incurring undue costs for the operator. Additionally, repairs inside tanks take a long time, especially when material purchases, such as certified steel plates, are required. Therefore, operators are interested in being able to accurately predict when structural elements must be repaired. Despite recent efforts to address this problem, accurate modeling of corrosion growth remains a challenge, mainly due to its complexity and inherent uncertainties. This work proposes the use of a regression tree model, which is a well-known machine learning technique, with the purpose of predicting when and what structural elements of FPSO tanks should be repaired. A prediction model was created by learning and testing from a real data set to estimate corrosion loss as a function of the type of structural element, age, and the fluids surrounding it. The Classification and Regression Trees (CART) algorithm was employed. The results show potential application in the material purchase planning process, minimizing the critical inspection and repair path of the FPSO cargo tank, and preventing loss of storage capacity during operation.
Sondermann, M.; Chou, Sin Chan; Souza, Celia Regina de Gouveia; Rodrigues, Judith; and Caprace, Jean David (2023) Natural Hazards 0.
Southeast Brazil is occasionally affected by intense storm surges that cause coastal erosion, coastal inundation, destruction of local infrastructure, and floods. This work is aimed at identifying the large-scale atmospheric conditions favourable to causing storm surges that reach the coast of the Sao Paulo State in Southeast Brazil. Based on ERA5 reanalysis data from May between 1981 and 2010, storms were identified on 89 surge days. Storm surge days are characterized by a significant wave height that exceeds 2.5 m. These surge days were clustered into three atmospheric patterns. Cluster Pattern 1 contains 10 storm surge days characterized by a low-pressure centre near the coastline and winds blowing parallel to the coast. These surface conditions are combined with upward vertical motion at 500 hPa and an upper-level jet stream, which helps rain formation over the ocean. Cluster Pattern 2 contains 22 events. The main feature of this pattern is the long and wide wind fetch area over the ocean, which generates a large area of intense winds that allows a more efficient propagation of high waves. This pattern shows the most significant rainfall values over the coastal area. Cluster Pattern 3 presents the largest number of surge days, totalling 57. The atmospheric pressure gradient established by the high-pressure system and the elongated trough over the ocean produces intense southerly winds along the coast, which favour high waves in this region. Therefore, the described atmospheric patterns favourable to storm surge events can be applied to forecasting systems and contribute to storm surge alerts in the Sao Paulo coastal zone.
Marques, Crístofer H.; Pereda, Paula C.; Lucchesi, Andrea ; Ramos, Ramiro F.; Fiksdahl, Olav; Assis, Luiz F.; Pereira, Newton N., and Caprace, Jean David (2023) Marine Policy 0(147):105334.
To reduce greenhouse gas emissions from maritime transport, the International Maritime Organization has been studying measures to be implemented in the short term. However, there is a need to carefully analyze the impact of these measures on transport costs. The present work presents an assessment of cost and CO2 emissions from mandatory speed reductions on the world merchant ship fleet. Considering the product usually transported by each ship type and the distance navigated, expenditures and CO2 emissions are calculated to perform a cost-effectiveness analysis. Results reveal that a given speed reduction is more beneficial for some regions and ship types than for others. Higher speed reductions were found to be environmentally beneficial but significantly increase the annual seaborne transport cost. Finally, the cost-effectiveness analysis shows that the cost per avoided ton of CO2 emission ranges between USD 23 and USD 58, in 30% and 40% speed reduction scenarios, respectively.
Fahrnholz, Stefan Faller ; Caprace, and Jean David (2022) Ocean Engineering 257:111642.
In order to estimate the installed propulsion power aboard a boat, naval and ocean engineers make use of tools to assess the hull resistance through the water. It allows the designer to investigate the effect of changes on the hull parameters during the project’s first steps when there is still freedom for modifications. The available models to predict the resistance of sailboats estimate the residual resistance, while the frictional component is calculated based on ITTC-57. This approach leads to difficulties at low speeds since the calculated frictional resistance is larger than the total resistance obtained from the experiment. Therefore, its application is restricted above a minimum speed. Moreover, the available models consist of several sub-models, one for each Froude number. The present work proposes a unique model to predict the total resistance of bare-hull sailboats based on machine learning. Three systematic series were used as input. The best machine learning model could predict the total resistance efficiently even for small Froude numbers. With the presented model, the designer will have a unique tool capable of quickly predicting the total resistance of bare-hull sailboats including at low speeds. Both the input data and the predictive model are shared in complementary digital material.
Ferreira, Ricardo dos Santos; Lima, João Victor Padilha de; and Caprace, Jean-David (2022) Ocean Engineering 255:111439.
Regulations on Greenhouse Gas (GHG) ship's emissions and air pollutant are becoming more restrictive. Therefore, a big effort is being put into ship efficiency discussion, specially on predictive models related to route optimization, fuel consumption and air emissions. This paper compares machine learning predictive algorithms, based on the following techniques: least-squares, decision trees and neural networks, to estimate ship propulsion power between two 8400 TEU container ships from the same series. Additionally, the influence of having a predictive algorithm trained with data of its sister ships is investigated. The data used in this study were recorded from 2009 to 2014 reaching almost 290,000 entries. The results indicate that random forest regression model and decision trees ensemble models have the best fit for this purpose. It has also confirmed the feasibility of predicting the delivered power of a ship having a machine learning algorithm feed with a sister ship information despite differences in the route and/or operating conditions.
Cepeda, Maricruz Fun Sang (2022) Examines in Marine Biology & Oceanography 5(1).
Marques, C. H.; Caprace, J.-D. (2020) Applied Ocean Research 97(65535):1-11.
The present work aims to provide a comprehensive approach to assist within the early-stage project of ship energy systems. This integrated approach enables the optimization of design, synthesis, and operation, considering economic and technical aspects, as well as route weather. A Differential Evolution optimization algorithm is used to maximize the net present value of the system. Constraints are considered to avoid propellers presenting strength, cavitation and vibration concerns. The case study is designed using three liquefied natural gas carriers of different cargo capacities sailing between Lake Charles and Tokyo Bay, via the Panama Canal. The approach is shown to be effective to find an optimal solution quickly and highlights the need for employing constraints to avoid future technical concerns. The approach also succeeded to quantify the gain of the net present value using the economy of scale, i.e. using bigger ships, and higher service speeds.
Martins, I. D.; Moraes, F. F.; Távora, G.; Soares, H. L. F.; Infante, C. E.; Arruda, E. F.; Bahiense, L.; Caprace, J.-D.; Lourenço, M. I. (2020) Ocean & Coastal Management 184(65535):1-11.
Regardless of the economic activity, decommissioning decisions are often highly complex. This is due to the diversity of operational and local parameters, as well as the multitude of stakeholders involved, who generally have conflicting interests. This sets up a challenging multi-criteria decision problem on the activities to be carried out during the decommissioning process. This paper aims to present an overview of decision-support tools applied to decommissioning, and covers many economic sectors, with a focus on the oil and gas sector and on multi-criteria decision analysis (MCDA) methods. The paper delves deep into the aspects to be considered before reaching a decision, examining the experiences and methods found both in industrial reports and in academic papers.
Cepeda, M. A. F.; Pereira, N. N.; Kahn, S.; Caprace, J.-D. J. E. M. (2019) Marine Systems & Ocean Technology 0.
Maritime transport is responsible for about 2.5% of global greenhouse gas emissions representing around 1000 million tons of CO 2 annually. The situation of shipping emissions that strongly depends on future economic grows is aggravated by the fact that global green house gas (GHG) emissions are predicted to increase between 50 and 250% by 2050. This is not compatible with the internationally agreed goal of keeping global temperature increase below to 2∘C compared to pre-industrial levels, which requires worldwide emissions to be at least halved from 1990 levels by 2050. Furthermore, ship owners are facing barriers implementing energy efficiency technologies to reduce CO2 mainly due to reliability, and financial and economic constraints as well as due to the complexity of change. Energy consumption and CO 2 emissions of ships could be reduced by applying operational measures and implementing existing technologies. Further reductions could be achieved by implementing new innovative technologies. The aim of this study is to compare and review low carbon and advanced technologies that may help to reach international GHG reduction goals. A comparison table describing the different technologies, the estimated capital cost, technology readiness as well as the potential GHG reduction is drawn. The table also indicates if the technology suits better to new projects or to retrofitting. The comparison may help the key players to select the most convenient technology for their new projects. It will also be helpful for conversion of existing vessels.
I. D. Martins; F. F. Moraes; G.Távora; H. L. F. Soares; C. E. Infante; E. F. Arruda; L. Bahiense; J.-D. Caprace; M. I. Lourenço (2019) Ocean & Coastal Management 65535:1-20.
Regardless of the economic activity, decommissioning decisions are often highly complex. This is due to the diversity of operational and local parameters, as well as the multitude of stakeholders involved, who generally have conflicting interests. This sets up a challenging multi-criteria decision problem on the activities to be carried out during the decommissioning process. This paper aims to present an overview of decision-support tools applied to decommissioning, and covers many economic sectors, with a focus on the oil and gas sector and on multi-criteria decision analysis (MCDA) methods. The paper delves deep into the aspects to be considered before reaching a decision, examining the experiences and methods found both in industrial reports and in academic papers.
Marques, C. H.; Belchior, C. R. P.; Caprace, J.-D. (2019) Journal of the Brazilian Society of Mechanical Sciences and Engineering 0(41):1-11.
There is still room to establish a methodology to optimise marine propellers, considering design requirements of the vessel, and match it to an electric motor. The method proposed herein consists in an optimisation whose objective function is power required in the electric motor shaft, and design variables are the parameters of Wageningen B-screw series propellers. A differential evolution optimisation algorithm was programmed in MATLAB environment to assess a number of propeller designs. Technical constraints of strength, cavitation, and peripheral velocity were considered. An actual ferryboat designed to operate in a lake in south-eastern Brazil is proposed as the case study. The worst individual of the final population of propellers had its objective function increased by 25%, compared with the worst individual of the initial population, within only 123 s processing time. Substantially dissimilar propeller designs were found for direct and geared drive with open water propeller efficiency between 36.18 and 40.49%. The approach has shown significant gains as an early-stage design tool and highlighted the need for exploring a broad range of propellers to find the optimal motor–propeller matching.
Marques, C. H.; Belchior, C. R. P.; Caprace, J.-D. (2019) Ocean Engineering 0(181):161-172.
Developing design tools to make more information available sooner is desirable because decisions of the greatest impact are made in early stages of ship design. Moreover, there is still room for improvement in the optimisation of energy system selection considering an integrated approach. Therefore, the present work aims to provide a comprehensive early-stage approach to optimise the design, synthesis and operation of a marine energy system for liquified gas carriers, considering their economic and technical aspects, and also weather along the route. Constraints are used to avoid propellers that could present issues concerning strength, cavitation and vibration. Various propellers, engines and operational profiles can be assessed with this approach. A differential evolution optimisation algorithm that maximises the net present value is applied. This part of the study details the approach that we have developed, while the case study, results and discussion, and the main conclusions are given in Part B. Different parameters can be set up in each route-track, which enables various operational profiles and sea conditions to be considered to seek the highest net present value. The proposed approach is expected to be able to automatically search a broad range of possible alternatives and then make small refinements to achieve the optimal arrangement.
Marques, C. H.; Belchior, C. R. P.; Caprace, J.-D.; Martini, Alberto (2019) Journal of Marine Sciences and Engineering 7(20):1-12.
Increasing environmental demands, alongside the planned penetration of natural gas as marine fuel, have rendered dual-fuel engines as an attractive prime mover alternative. In this context, knowing the specific fuel consumption is essential to selecting the most efficient engine. The specific fuel consumption can be approached by simulation models with varying levels of complexity that are either implemented by basic programming languages or simulated by dedicated packages. This study aims to develop a simplified model to predict the specific fuel consumption of dual-fuel two-stroke marine engines driving fixed or controllable pitch propellers. The model relies on clear trends approachable by polynomials that were revealed by normalizing specific fuel consumption. This model requires only the value of specific fuel consumption at a nominal maximum continuous rating to predict the engine consumption at any specified rating, including at partial engine load. The outcome of the study shows that the maximum deviations regarding the two simulated engines did not exceed −3.6%. In summary, the proposed model is a fast and effective tool for optimizing the selection of dual-fuel, two-stroke Diesel engines regarding fuel consumption.
Marques, C. H.; Belchior, C. R. P.; Caprace, J.-D. (2019) Ocean Engineering 174:96-107.
The present work aims to provide a comprehensive early-stage approach to optimise the design, synthesis and operation of a marine energy system for liquified gas carriers, considering their economic and technical aspects, and also weather along the route. Part A of this work details the approach that we have developed while Part B will summarise the first part, it will then describe the case study, results and discussion, as well as the conclusion. Various propellers, 16 engines and 4 operational profiles are assessed. In this part, we will apply a differential evolution optimisation algorithm, whose objective function will be maximised as the net present value. The case study is designed to use a liquefied natural gas carrier of 175,000 m3 sailing between Lake Charles (USA) and Tokyo Bay (Japan), via the Panama Canal. All of the suitable matchings for 15,023 propellers are found. This approach shows a gain of 22% between the worst individual of the initial population and the worst individual of the final population. The required brake power is approximately 22% higher for rough weather than for still water. A difference of over 120% was found by comparing varied matchings of economic scenarios and fuel profiles. Our approach shows a significant gain and highlights the value of exploring a broad range of energy system configurations in an integrated manner, especially considering the weather conditions.
Floriano Pires Junior (2019) Maritime Policy & Management Journal 46(7): 831-844.
The literature on valuation of time charter contracts and real options in shipping generally relies on the complete markets hypothesis and the risk-neutrality of agents. However, these assumptions fail completely in some shipping market segments. This study proposes a numerical approach—based on discounting the certainty equivalent payoff at the risk-free rate—which incorporates the agent’s risk preferences through an exponential utility function. The method comprises an iterative Monte Carlo nested simulation with the real probability measure. This method is applied to a case of Suezmax tankers. The stochastic evolution of the time charter rates is modelled as a geometric mean-reverting process. The case study supports the applicability of the proposed method and evidences that the effect of risk preference may be significant, mainly for more risk-averse agents. Although the method involves intensive computation, it has the benefits of theoretical ease and flexibility, which could encourage utilisation by practitioners.
Muhabie, Y. Tekle ; Rigo, P. ; Cepeda, M. A. F. ; D'Agosto, M. A. ; Caprace, J. D. J. E. M. (2018) Ocean Engineering 149:279-290.
The wind industry is facing new challenges due to the planned construction of thousands of offshore wind turbines all around the world. However, with their increasing distance from the shore, greater water depths, and increasing sizes of the plants, the industry has to face the challenge to develop sustainable installation procedures. Important limiting factors for offshore wind farm installation are the weather conditions and installation strategies. In this context, the focus of this research is the investigation of the most effective approach to installing offshore wind farms at sea, including the effects of weather conditions. This target is achieved through the implementation of a discrete-event simulation approach which includes the analysis of the environmental conditions, distance matrix, vessel characteristics, and assembly scenarios. The model maps the logistics chain in the offshore wind industry. A deterministic and a probabilistic metocean data method have been compared and cross validated. The results point to a good agreement between the two considered models, while highlighting the huge risks to the time and cost of the installation due to the stochastic nature of the weather. We suggest that simulations may improve and reduce these risks in the planning process of offshore wind farms.
Marques, C. H.; Belchior, C. R. P.; Caprace, J.-D. (2018) Applied Energy 232:187-196.
Dual-fuel Diesel engines have become the most interesting alternative for liquefied natural gas carriers (LNGCs) since they are able to use boil-off gas as fuel. However, there is a lack of studies about the optimisation of propulsion system selection considering weather conditions in an integrated approach. Thus, the present work aims to provide a comprehensive approach to perform the optimisation of engine-propeller matching for an LNGC under rough weather. A weather condition was included in the assessment of total resistance and thereby affected the propeller’s open water efficiency, shaft speed and brake power. Constraints were included to the approach in order to avoid propellers that could present issues concerning strength, cavitation and vibration. A differential evolution optimisation algorithm was applied to minimise the fuel expenditure of propulsion for a round trip. The case study was designed using an LNGC with cargo capacity of 175,000 m3 sailing in laden condition from Lake Charles to Tokyo Bay, via Panama Canal, and returning in ballast. All suitable matchings for 5346 propellers were found in 2.8 h and over 28% of them were constrained. The method has shown gains up to 19% of fuel expenditure reduction. The required brake power was approximately 20% higher for rough weather than for still water. Therefore, the approach used here has shown a significant gain and highlighted the value of exploring a broad range of propellers and engines in an integrated manner, as well as considering the weather condition.
Marques, C. H.; Belchior, C. R. P.; Caprace, J.-D. J. E. M. (2017) Marine Systems & Ocean Technology 12(3):138-149.
This study aimed to address the state of the art of marine diesel engines computer simulation models and the main computer applications. There are simple models based on transfer function or more complex models based on computational fluid dynamics. The models may be either implemented through basic programming languages or simulated through dedicated packages of internal combustion engine simulation. Owing to the recent interest to reduce the gas emission, dual-fuel engines are increasingly being used as primary propulsion in merchant ships. In this context, a simplified model of marine dual-fuel low-speed diesel engine has been developed. Through the normalisation of specific fuel consumption and exhaust gas data, clear trends approachable by polynomial curves or surfaces were revealed. Thus, by using the proposed model and knowing the characteristics of an engine at its nominal maximum continuous rating, it is possible to predict the engine operation in any design point on the engine layout diagram, even at part load. The maximum deviations regarding the two simulated engines did not exceed −3.4%. Summarising, the developed model is a simple and effective tool for optimising the selection of dual-fuel low-speed diesel engines to be applied in ship propulsion systems.
Caprace, J.-D.; Fu, G.; Carrara, J. F.; Sang H. R.; Shin B. (2017) Marine Structures 57:69-84.
Steel stiffened panels assembled by fusion welding are widely used in the design of marine structures. Although the numerical model calibrated via experimental measurements is becoming a common solution, certain unrealistic result from numerical welding simulation are commonly observed due to the use of different software and modeler practices. Each selected parameter such as mesh size, material modelling, heat input, boundary conditions play an important role in the finite element model, and directly impact the final results. Therefore, key challenges must be addressed in order to analyse in what extent modeler practice and software influence the reliability and accuracy of the results. This paper propose a benchmark study to understand the influence of the modeler's practice and FEM codes on the welding simulation results. The welding residual stress and distortion of a ”T-joint” weld are analyzed numerically under various material models, boundary conditions and heat inputs. Then, results of various 3D thermo- mechanical simulation models are confronted to a well reported experimental results. The findings show that the difference of modeler practice may have considerable effects on welding residual stresses, i.e. 20% difference whereas welding distortions are less sensitive to the user decisions i.e. 12% difference. Finally we suggest that the sensitive parameters of welding simulation such as equivalent heat source and material modelling need a general guide in order to evolve from a reproduction tool to a prediction method for any welding procedures.
Rigo, P.; Bayatfar, A.; Buldgen, L., Pire, T.; Echeverry, S. ; Caprace , J.-D. (2017) Ship Science & Technology 11(21):9-27.
This paper includes the following parts: Ship Structure Optimization: methodology to perform ship scantling optimization, decreasing steel weight and keeping the production cost at an acceptable level. We first review the links between “Design” and “Optimization” and secondly define the place of “Ship Structure Optimization” within the general framework of a “Ship Optimization”. Ship impacts (Collision), with applications to navigation lock and dry dock gates: these gates have to be designed taking into account accidental loads, such as ship collisions. A new simplified analytical method is proposed, based on the so-called super-element method. This method was developed to rapidly assess the crashworthiness of the collided structure and avoid high computational effort of numerical simulations. Inland waterway Navigation and t he development in South America of Inland Water way Classifications. EMSHIP, European ERASMUS MUNDUS education program (www.emship.eu): the unique master's degree in Ship & Offshore Structures awarded by the prestigious European Erasmus Mundus Program. EMSHIP shares the outstanding experiences of educators, trainers, industrial partners and students in the rapidly developing areas of marine and offshore engineering industry.
Cepeda, M.A.F.; Assis, L.F.; Marujo, L.G.; Caprace, J.-D. (2017) Marine Systems & Ocean Technology 12(3):178-186.
Currently, container ships operators have implemented slow steaming (SS) strategies in their fleets to improve the profit margins by reducing operational costs. However, some ship owners are not yet convinced of this practice because the navigation time is increasing that cause a reduction of the number of travel per year of the ship. The use of speed reduction by liner shipping has been widely discussed in the literature. Nevertheless, this effect has not been studied in bulk carriers because they are navigating slower than container ships. This paper proposes a simulation model of a bulk carrier’s fleet composed by 13 ships from a unique ship owner in three conditions: the actual condition of navigation, the SS and the ultra-slow steaming. A discrete-event simulation model has been developed considering historical data of a bulk carrier fleet. The results obtained are the total fuel consumption, emissions and the cargo transported per year. These values are showing that the fleet can be operated with higher efficiency when the SS strategy is used. Indeed, the saving in fuel cost and emissions are balancing the reduction of the cargo transported per year.
de Araujo, A. O., Rezende Filho, M.; Pires Junior, F. C. M. (2017) Marine Systems & Ocean Technology 12(3):93-103.
The Merchant Marine Fund—FMM—is the main source of financing for shipbuilding and shipping industries in Brazil. As an official system, it operates under favoured and strictly regulated terms. Since the interest rates are subsidized, the shipyards are required to present a detailed ship construction budget. The FMM Agency and the commissioned governmental banks in charge of the loans management are supposed to assess those budgets to prevent overpricing and production inefficiencies. Historically, the budget assessment process has been conducted without formal technical foundation, relying on subjective judgement of the analysts. However, due to the evolution of compliance requirements in governmental institutions and projects, the need for technical improvement of FMM management has become evident. The Decision Support System discussed in this article was developed in this context. Besides the relevance as an analysis tool, in terms of the quality of the approved projects, the database is a valuable instrument, for example, to monitoring maritime industry evolution, design of ships and transport systems and shipbuilding supply chain evaluation. With these objectives, a Decision Support System was developed, aiming at integrating the functions of managing the capture and validation of the database inputs; structured and non-structured queries; statistical analysis of the main cost drivers; and assessment of the total cost of projects submitted by the builder and the owner. The present article discusses the main features and economic impacts of the FMM system. Moreover, the article aims at discussing the structure and functionalities of the Decision Support System.
Caprace, J.-D., Moita, J. V. (2016) Portos e Navios 58(662):46-47.
Operações portuárias mais rápidas e eficientes permitem operadores de embarcações a planejarem melhor suas jornadas e economizar combustível. Um arranjo melhorado de planos de baias e uma ferramenta de Simulação de Evento Discreto podem ajudar a aumentar a eficiência de terminais.
Buldgen, L.; Caprace, J.-D.; Rigo, P.; Le Sourne, H. (2016) Engineering Structures 131:380-393.
During an earthquake, lock gates are subjected to additional pressure since the water contained in the chamber is put into motion by the earthquake. It is difficult to assess the level of this pressure because the system is affected by a fluid–structure interaction. The gate deformations have an effect on the water pressure, which in turn affects the gate vibrations. A common approach, referred to as the added mass method, consists of simulating the fluid action by distributing lumped masses over the gate. However, this method has been questioned, since the calculation of the lumped masses is usually based on the Westergaard formula, which was derived assuming a perfectly rigid structure. Consequently, fluid–structure interactions may not be captured correctly. This paper proposes to investigate the validity of this approach for such problems and to explain why it might not be conservative. The numerical solutions of an added mass model and a fluid–structure interaction model are confronted. The results indicate that the added mass method may eventually lead to conservative results depending on the type of damping used in the model. Based on these observations, some recommendations are suggested to improve the design of lock gates subjected to earthquakes.
This paper describes the development of a semi-empirical computational method to solve the dynamic equilibrium problem for planing hulls with arbitrary geometry, including variable deadrise angles along the length. The method is based on Savitsky׳s method (1964) and it is named ‘Virtual Prismatic Hulls Method’, allowing for the determination of the intensity of the lift force and the resulting center of pressure, in order to determine the dynamic equilibrium position and the drag force, at the fully developed planing regime, for any arbitrary, non-prismatic hard chine hull form. Results produced by the method are presented and investigated and their applicability is established and compared with experimental results of well-known systematic series of planing boats.
Suzen, R. O., Caprace, J.-D. (2015) HANSA International Maritime Journal 0(12):82-83.
Faster and more efficient port operations can allow vessel operators to better plan their journey and save fuel. An improved bay plan arrangement and a Discrete Event Simulation tool can help to improve terminal productivity
Langer, Y.; Bay, M.; Crama, Y.; Bair F.; Caprace, J.-D., Rigo, P. (2015) Ship Technology Research 52(3):141-147.
A scheduling problem arising in factories producing large building blocks is modelled applying optimization techniques. The application is a shipyard workshop producing prefabricated keel elements. The objective is to maximize the number of building blocks produced in the factory during a certain time window. The solution combines a Guided Local Search heuristic with Fast Local Search techniques. A final discussion explains the additional real-life issues arising in the industrial application and how firm-specific constraints can be conveniently considered by the model.
Caprace, J.-D.; Losseau, N.; Bair, F.; Buldgen, L.; Archambeau, D. (2015) Ship Technology Research 54:177-183.
Czarneski, F; Pires, F. (2015) Revista Gestão Industrial 11(2):229-244.
Na última década houve uma retomada de investimentos na construção naval brasileira o que resultou em uma expansão e modernização da capacidade produtiva dos estaleiros nacionais. Os estaleiros nacionais ainda precisam atingir um nível de excelência operacional compatível com o observado nos países líderes de mercado O trabalho apresenta tópicos adotados por estaleiros estrangeiros bem sucedidos e que podem ser implantadas pelos estaleiros brasileiros com o intuito de torná-los competitivos mundialmente. Para isso, realizou-se um estudo de caso em um estaleiro nacional, cujo foco foi o levantamento das tecnologias e processos em uso nesse estaleiro e a classificação com relação às melhores práticas mundiais (benchmarks). Um método de benchmarking desenvolvido para construção de navios foi utilizado no presente estudo. O trabalho pode servir como fonte de informações para realizar ajustes para melhorias em processos produtivos, redução de tempos de ciclo e melhor utilização da mão-de-obra. Dessa forma, pode contribuir para posicionar a situação atual do estaleiro e verificar as necessidades para torná-lo competitivo internacionalmente.
Santos, A.; Junkes, L.; Pires Jr, F. (2014) Maritime Economics & Logistics 16(1):72–91.
Volume-wise, seaborne crude oil represents close to 45 per cent of all internationally traded crude oil – thus remaining as the modern world primary source of energy. The usual focus in seaborne freight rate forecasting literature is the spot rate, whereas, on the other hand, a limited amount of literature has been directed towards period charter rates. To the same extent, there is a scarce amount of literature available dealing with the use of artificial neural networks (NNs) in forecasting seaborne transport market rates. This article focuses on applying NNs to period charter rates forecasting of very large crude carriers. The performance achieved for 1- and 3-year period charter rate time series by two different NN models (multi-layer perceptron and radial basis function (RBF)) is benchmarked against a more elementary performance delivered by an autoregressive integrated moving average (ARIMA) model. We find that NN modelling delivers encouraging end results outperforming the benchmark model (ARIMA). We can also point out that NN using RBFs delivers the best overall predictive performance.
J. Caprace and C. Petcu and M.G. Velarde and P. Rigo (2013) Journal of Marine Science and Technology 18(3):404-417.
In this article we describe the development of a tool that allows planners to efficiently and effectively plan space within valuable areas of a shipyard. Traditionally, space is considered as resource; however, it is difficult to accurately account for and plan its consumption with the currently available planning software’s. The spatial scheduling tool described in this article can be used by planners to manually or automatically reserve space within the shipyard for construction of large blocks over the entire erection period of the ship. The software is coupled with a heuristic optimization solver inspired by an algorithm used for "3D bin-packing problems." The result is the ability to efficiently generate and compare multiple space allocation alternatives in a reduced time with the ultimate goal of maintaining the critical ship erection schedule. A better solution than manual or semi-automatic allocation of blocks can be obtained through the optimization module.
Pires Jr., F. C. M.; de Carvalho, F. S. (2013) Transportation Planning and Technology 36(5):435-449.
This paper proposes a multicriteria methodology for the analysis of investment in inland waterway infrastructure projects, taking into consideration allocative efficiency, the effect on regional development and environmental impact. The methodology is based on an analytic hierarchy process approach. As an example, the case of an important Brazilian Amazonian project is analysed. The Marajó Island waterway project has been under discussion for a long time in Brazil, as it is located in an environmentally sensitive area, but at the same time it is considered to have a critical impact on regional economic development. A Monte Carlo simulation is performed to take into account uncertainties related to knowledge failure on project impact or on the conditions that determine the relative importance of the decision criteria.
Pires Jr., F.; Assis, L. F. ; Rezende Filho, M. ; Vieira, C L B ; Botelho, S.S.C. ; Duarte Filho, N. (2013) Marine Systems & Ocean Technology 8(2):87-93.
The Brazilian shipbuilding industry is presently showing significant recovery prospects. However, there are some problems affecting this process. The high level of builder’s risk perceived by the owners and, mainly, by banks, insurance companies and other stakeholders, is likely the most critical. The main instrument to keep the risk in acceptable levels is a strict control of the construction progress. However, some shipowners have been employing control systems that are excessively complex, detailed and expensive, but, at same time, not sufficiently effective. This paper presents the main characteristics of a computer system developed to provide a broad control over the construction progressand financial balance as well as a continuous risk assessment.
Caprace, J.-D.; Rigo, P. (2012) Computer-Aided Design 44(3):203-208.
The paper introduces an innovative complexity metric for passenger ships taking into account the shape complexity of steel parts, the assembly complexity and the material complexity. The goal is to provide the designer with such information throughout the design process so that an efficient design is obtained at the first design run. Real-time assessment of complexity and quality measurements is rather imperative to ensure efficient and effective optimality search, and to allow real-time adjustment of requirements during the design. Application and validation on a real passenger ship show that the new method is effective in giving a complementary aid to decision process for ship designers.
Caprace, J.-D.; Rigo, P. (2012) Journal of Marine Science and Technology 17(2):216-230.
Cost is perhaps the most influential factor in the outcome of a product or service within many of today’s industries. Cost assessment during the early stage of ship design is crucial. It influences the go, no-go decision concerning a new development. Cost assessment occurs at various stages of ship design development. Economic evaluation as early as possible, in the design phase, is therefore vital to find the best pricefunction compromise for the ship projects. The authors have developed a feature-based costing model for cost effectiveness measurements intended to be used by ship designers for the real time control of cost process. The outcome is that corrective actions can be taken by management in a rather short time to actually improve or overcome predicted unfavourable performance.
Floriano C. M. Pires Jr; Augusto R. Antoun (2012) Int. J. of Computer Applications in Technology 43(3):87-93.
In the near future, the demand for offshore supply vessels in Brazil will be driven by the activities induced by the bids carried out by the regulatory agency, ANP. The likely tendency is to increase the number of bids and consequently, the demand for vessels in the coming years. The proposed model consists of a Monte Carlo simulation of the offshore oil exploration and production projects. The model considers some parameters that aim at capturing the effect of the operators patterns, water depth, duration of seismic research and exploration and drilling work, number of wells, geographic location and geological risk. An estimate is obtained for the additional offshore supply vessels demand, for the period of 2006-2008.
Pires Junior, F. C. M.; Assis, L. F. ; Rezende Filho, M. (2012) African journal of business management 6(25):7397-7402.
Initially, this paper presents a methodology for analysis of investment in a tanker ship, based on Monte Carlo simulation of auto-correlated series of time-charter rates and prices of new building and second hand ships. Subsequently, a real options analysis is introduced, considering the possibility of project abandonment. The method is employed for evaluation of the investment in a suezmax tanker. The results indicate that the investment analysis outcome is significantly sensitive to the consideration of the managerial flexibility to project abandonment. Finally, the paper discusses the effect of the decision maker’s risk attitude on the abandonment option value.
Caprace, J.-D.; Rigo, P. (2011) Journal of Marine Science and Technology 16(1):68-75.
An innovative complexity metric is introduced that provides a way to compare similar or different ship types and sizes at the contract design stage. The goal is to provide the designer with this information throughout the design process so that an efficient design is obtained during the first design run. Application to and validation on real passenger ships indicate that there is a significant correlation between the error in an engineer’s judgement of complexity and the cost assessment error. It follows that this tool could be used to improve knowledge of the ship’s complexity at the contract design stage, and even to try to optimise the design if the complexity criteria are not fixed by the shipowners.
Pires Junior, F. C. M.; Cipriano, W. Q. M. ; Assis, L. F. . (2011) Journal of Transport Literature 5(1):4-32.
The pricing process in the international market of second-hand ships is extremely complex. This paper aims at analyzing the hypothesis that the builder country is one of the significant explanatory variables. The sample analyzed was composed of tankers, bulk carriers and full-containerships with less than 20 years, sold between 2003 and 2005. The econometric analysis has pointed out robust statistical evidence that bulk carriers built in Japan tend to have higher expected value of second-hand price, ceteris paribus. In the cases of the other classes of ships, sample bias due to different reasons precluded any conclusive analysis.
Caprace, J.-D.; Bair, F.; Rigo, P. (2010) Mathematical Modelling in Civil Engineering 2.
In the scantling design of a passenger ship, minimum production costminimum weight and maximum moment of inertia (stiffness) are conflicting objectives. For that purpose, recent improvements have been made to the LBR-5 software (French acronym of “Stiffened Panels Software”, version 5.0) to optimize the scantling of ship sections by considering production cost, weight and moment of inertia in the optimisation objective function. A real multi-criterion optimisation of a passenger ship is presented in this paper. Results highlight that LBR-5 is competitive software to optimise scantling of ships at very early design stage with management of critical problems studied normally at a later step of the design.
Caprace, J.-D.; Bair, F.; Rigo, P. (2010) Marine Structures 23(3):288-302.
Numerous real-world problems related to ship design can be solved by various alternatives. However, the scantling design has conflicting objectives such as minimum production cost, minimum weight and maximum moment of inertia (stiffness). Therefore a multi-purpose solution had to be settled in order to meet all these requirements at once. Ship design is a complex endeavour requiring successful coordination of many different disciplines, both technical and non-technical. Basic design is the least defined stage of the ship design process and seeks to define the optimal amidships section structure. For that purpose, recent improvements have been made to a numerical tool in order to optimise the scantling of ship sections by considering production cost, weight and moment of inertia in the optimisation objective function. A multi-criteria optimisation of a LNG carrier is conducted in this paper to illustrate the analysis process. Pareto frontiers are obtained and results have been validated by the Bureau Veritas rules. The methodology presented in this paper has demonstrated its effectiveness in optimising scantling of ships at a very early design stage thanks to a management of critical problems usually studied at a later stage of the design.
Pires, F. C. M.; Lamb T.; Souza, C. (2009) Int. J. of Business Performance Management 11(3):216-235.
The purpose of the paper is to present a methodology for shipbuilding performance assessment, taking into account the characteristics of the shipyard, the production pattern and the industrial environment of the country or region. A Data Envelopment Analysis (DEA) model to assess shipyard performance is proposed. An Analytic Hierarchy Process (AHP) method for obtaining an indicator of the extent to which the industrial environment of a region is favourable to shipbuilding development is introduced. The model was applied in comparing the efficiency of 12 shipyards in Japan, South Korea, China and Europe. The analysis was supported by visits to each shipyard in the sample and interviews with key technical and managerial personnel. The results indicate that some shipyards that do not have the highest technological level in the world are highly efficient in attaining performance indicators, even in conditions less favourable than for the global leaders.
Turan,O.; Ölçer, A. İ., Lazakis, I.; Rigo, P.; Caprace, J.-D. (2009) Ships and Offshore Structures 4(9):107-125.
The aim of this paper is to investigate the effect of the change in structural weight due to optimisation experiments on life cycle cost and earning elements using the life cycle cost/earning model, which was developed for structure optimisation. The relation between structural variables and relevant cost/earning elements are explored and discussed in detail. The developed model is restricted to the relevant life cycle cost and earning elements, namely production cost, periodic maintenance cost, fuel oil cost, operational earning and dismantling earning. Therefore it is important to emphasise here that the cost/earning figure calculated through the developed methodology will not be a full life cycle cost/earning value for a subject vessel, but will be the relevant life cycle cost/earning value. As one of the main focuses of this paper is the maintenance/repair issue, the data was collected from a number of ship operators and was solely used for the purpose of regression analysis. An illustrative example for a chemical tanker is provided to show the applicability of the proposed approach.
Pires, F. C. M.; Lamb T. (2008) Maritime Policy & Management 35(5):491-502.
Shipbuilding is the subject of public policies in a number of countries, as it is considered a strategic industry and has an impact on employment levels in many regions. Establishing performance targets can be a challenge to shipbuilding policy makers. This paper suggests an approach to this problem, based on the Data Envelopment Analysis (DEA) technique. This approach makes it feasible to estimate productivity and building time potential, taking into account the output pattern, technological level and quality of the industrial environment of the country or region. The methodology is applied to the analysis of the competitive potential of some Brazilian shipyard models. The benchmarking analysis was carried out for a sample of shipyards from the world's principal shipbuilding blocks.
Richir, T.; Caprace, J.-D.; Losseau, N.; Pircalabu, E.; Toderan, C.; Rigo, P. (2007) Ships and Offshore Structures 2(4):339-345.
The LBR-5 software allows optimizing ship structures according to objectives of higher inertia, less weight and/or lower cost. This last criterion offers the choice between two approaches of calculation. The first approach is based on a simplified assessment of the cost in which the total cost is described by rather simple analytical functions which bring into play on the one hand the design variables and on the other hand empirical parameters. In the second approach, the calculation of the cost is based on data specific to the shipyard. The material cost is analyzed according to the first approach while the cost of the labor considers each relevant operation of the ship building with respect to the LBR-5 model. A survey of all the tasks was carried out at Aker Yards France, and a thorough study made it possible to develop assessment tools of the labor cost for each operation as functions of the design variables. Plate straightening operations are also considered in this analysis. This paper presents a cost-based optimization study carried out on a large passenger ship structure with more than 600 design variables, by the use of the detailed approach for the cost calculation. The structural model has been formulated on the basis of technical documentation prepared by Aker Yards France. The loads and strength criteria applied on the model are considered according to classification society rules (Bureau Veritas). Results and conclusions of the study are presented.
Schachter, R. D.; Fernades, A. C. ; Bogosian Neto, S.; Jordani, C. G.; de Castro, G. A. V. (2006) Journal of Offshore Mechanics and Arctic Engineering 128(4):294-303.
The objective of this work is to describe and discuss a design process organization approach named “solution-focused design.” This method has been created and used successfully for advanced marine vehicles (AMV), ship and offshore platform design over the last ten years with reasonable advantages. It was first created in a context where the decision of what concept to be adopted supersedes the use of the classical design spiral, suggesting a combination of the spiral with morphological charts, since the design processes of the concurring concepts are completely different from each other. The advantages are in terms of allowing for the introduction of creative ideas into the conceptual design process, eventually leading to an innovative product or design solution, establishing a sound design sequence and rationalizing the search for design tools and knowledge, parameter and task organization and classification (free variables, restrictions, performance specifications), and the design process itself. In this work the solution-focused design process is described and compared to some usual ones, which normally rely on “problem-focused” strategies for problem solving. It is shown how the process evolves from a preestablished scenario and a design briefing or specification to a design methodology. This is done in brainstorming sessions, using sketches and interactive design flowcharts (similar to design spirals), adapted for this approach. The objective is to provide the designer with means to define quickly and efficiently the optimal configuration of the design, while incorporating novelties into it. In order to show some features of the approach, three different examples of designs previously developed are presented: one for a SPAR Buoy Platform, another for a floating production, storage, and offloading unit (FPSO), and another for the feasibility and concept of a “fully submersible fast boat.” This last one shows features from which the method evolved from AMV’s to offshore platforms’ design: detailed morphological comparisons of different concepts, in this case, of means of support.

Conference Proceeding

Bobadilla, Roberto Bore; Barbosa, Nicholas Miranda; Vera, Sergio; Lourenço, M.I.; Caprace, Jean David , ASME (2024)
Proceedings of Conference 43rd International Conference on Ocean, Offshore and Aerctic Engineering (OMAE2024) . Volume 1, Singapore. ASME, ASME.
Maintenance and continuous monitoring of offshore structures and ships are essential in ensuring the integrity and safety of these high-value assets. Manual inspection methods are labor intensive , time-consuming, and often dangerous. Unmanned Aerial Vehicles (UAVs) also called drones equipped with cameras offer a promising solution for efficient data collection. This research addresses the need for automated corrosion detection and classification in images captured by UAVs, revolutionizing asset maintenance practices. Despite advances in computer vision and deep learning, the development of a robust and accurate deep learning algorithm for the automatic detection and classification of corrosion in UAV-captured images remains an underexplored area. Existing methods lack the precision and adaptability required to meet the rigorous demands of offshore asset management. The primary objective of this research is to develop a state-of-the-art deep learning algorithm that can automatically detect and classify corrosion in images of offshore structures and ships, acquired through UAVs. By achieving this goal, we aim to enhance the efficiency and accuracy of corrosion monitoring, thus extending the service life and safety of these critical assets. We employ YOLOv8 (You Only Look Once), a cutting-edge object detection model, as the core of our approach. The model is fine-tuned using transfer learning, leveraging pre-trained weights from a vast dataset to adapt to our specific corrosion detection task. The algorithm is trained on a diverse dataset of corrosion images. Our deep learning algorithm demonstrates good performance in corrosion detection and classification. Through extensive testing on UAV-captured images, it consistently achieves high accuracy, sensitivity, and specificity. The algorithm's real-time processing capabilities enable swift responses to corrosion-related issues, ensuring timely maintenance interventions. In conclusion, our research presents a novel deep learning approach for automatic corrosion detection and classification in UAV-captured images * Corresponding author: jdcaprace@oceanica.ufrj.br of offshore structures and ships. The utilization of YOLO V8 with transfer learning significantly improves the accuracy and efficiency of corrosion monitoring. This result contributes to the continuous improvement of asset management practices, offering enhanced safety and extended service life, ultimately minimizing costs and environmental impact in the offshore industry.
Távora, Giselle Da Silva; Infante, Carlos Eduardo Durange de Carvalho; Nicolosi, Eduardo Ribeiro; Ferreira, Claudio Violante; Lourenço, M.I. ; Caprace, Jean-David , ASME (2024)
Proceedings of Conference 43rd International Conference on Ocean, Offshore and Aerctic Engineering (OMAE2024) , Singapore. ASME, ASME.
As Brazil's offshore fields age, the need for decommissioning subsea structures is intensifying. While the importance of de-commissioning is well understood, the current literature lacks a detailed stochastic approach for the decommissioning of subsea pipelines. This paper fills the gap by presenting a stochastic multi-criteria decision analysis (MCDA) to aid in determining the most appropriate decommissioning option. The method includes a way to handle data variability and incorporates decision-makers' preferences using MCDA techniques. Through a case study of a rigid pipeline in Brazil's Cação field, various decommission-ing strategies are evaluated against criteria like safety, social, environmental impact, and cost. The study considers various decommissioning alternatives, including leaving the pipeline in place, rock deposition at the pipeline ends, total removal by cutting and lifting sections, and complete removal by reverse reel lay. The study, using Monte Carlo simulations to account for data uncertainties, concludes that leaving the pipeline in place is the preferable choice. This research provides a comprehensive tool for transparent decommissioning decision-making in the face of uncertainties, demonstrating its effectiveness in practical scenarios.
Lourenço, M. I. ; Caprace, J.-D.; Palhano, L. ; Sant'Ana, J. F.; A. M. Angelo; Nicolosi, E. R.; Ferreira, C. V. ; de Freitas, L. R. , OTC Offshore Technology Conference (2024)
Proceedings of Offshore Technology Conference , Houston, Texas, USA, May 2024. , Houston, Texas, USA. OTC Offshore Technology Conference, OnePetro.
Decommissioning decision-making is an integral and complex process in various industries, such as nuclear power plants, oil and gas facilities, and industrial manufacturing plants. The planned service life of many offshore oil and gas facilities is coming to an end. Decommissioning these facilities has emerged as a crucial task due to significant and uncertain expenses, high operational risks, potential social consequences, and environmental considerations related to the marine ecosystem. This paper proposes an evolving methodology to assist a sustainably oriented decision process for decommissioning the subsea infrastructure of offshore oil and gas facilities. Decision-making plays a crucial role in the search for a balance between the concerns of stakeholders, such as oil and gas companies, government bodies, environmental protection organizations, marine and coastal environmental users, and local communities. The decision problem is often complex since, most of the time, no ideal option is available to satisfy all criteria. Decision-makers can employ advanced approaches to address this problem, such as the multi-criterion decision analysis presented in this work. This methodology improves the decision-making process by ranking the various options for decommissioning subsea oil and gas assets. The model considers six criteria: Safety, Environment, Waste Management, Technical, Social, and Economic. Multiple decommissioning alternatives are compared, where groups of structures with similar technical and environmental characteristics are identified and analyzed together. The paper summarizes the application of this methodology in decommissioning different fields off the Brazilian coast, demonstrating excellent performance in helping the decision-making process. The methodology proposed addresses the growing concern about properly disposing of the decommissioned materials in an environmentally responsible manner with guidance from life-cycle assessment methods. Furthermore, attention is given to sustainability-related concerns regarding emissions generated during decommissioning operations. A set of tools was developed to help the stakeholders to have a better understanding of the results. The methodology contributes to reducing the subjectivity of the decision by assisting a project that is still conceptual to make decisions based on solid foundations raised through various databases and specialist knowledge.
Vieira, Joao Henrique; Kastner, Marvin; Caprace, Jean David (2024)
Proceedings of Conference: 35th PIANC World CongressAt: Cape Town, South Africa . PIANC, PIANC.
In the dynamic global container market, the top 10 ports controlled 33% of the total of 852 million TEUs in 2022, where the Port of Santos Complex (BRSSZ) holds the 46th position, handling approximately 4.5 million TEUs, with an annual storage capacity estimated at 5.6 million TEUs. (ALPHALINER, 2023; UNCTAD, 2023). Although PIANC's terminal planning guidelines provide a general equation for estimating terminal capacity (PIANC 158, 2014), this research aims to enhance dynamic capacity modelling and analysis by incorporating the logistic breakdown of cargo mix and establishing statistical premises. The primary objective is to present a technical analysis of capacity utilisation, serving as a strategic tool for both commercial and operational intelligence economic studies. This research used the Port of Santos logistic operators' competition as a case study, introducing an analytical framework that distinguishes between static and dynamic capacities across theoretical design and operational planning approaches. Data collection involves a comprehensive survey of technical information and the processing of economic indicators using statistics from masterplan reports, ANTAQ and SPA databases mainly. The results provided a technical data sheet and economic analysis of the container terminals at the Port of Santos, grounded in infrastructure surveys and dynamic capacity utilisation. In conclusion, the study emphasises the importance of adopting a strategic port intelligence perspective, focussing on the breakdown of the logistic flow quay-yard-gate and the modelling of the storage capacity. Recognising the critical trade-off between supply and demand, the findings guide decisions on opportune moments for investing in terminal asset expansion, influenced by monitoring competitors' capacity utilisation rates.
Moita, João Vitor Marques de Oliveira; Monteiro, Gabriel Premoli; Lourenço, M.I.; and Caprace, Jean David , SOBENA (2022)
29th International Congress on Waterborne Transportation, Shipbuilding and Offshore Constructions . Volume 29. SOBENA, SOBENA.
Ultra-deep-water exploration and production of oil and gas require the installation of complex subsea assets such as flexible risers, flow lines, manifolds, well heads, etc. The structural integrity of these assets is monitored through a costly repetitive inspection process that involves a fleet of remote operated vehicles (ROV) and ROV supply vessels (RSVs). Risk-based inspection (RBI) can be applied to partially mitigate some of these costs. However, there is still room for improvement that links RBI with offshore logistic optimization. This article presents a new methodology that minimizes operating costs and the risk of failure of subsea assets involved in the O&G industry. A discrete event simulation (DES) model is used to simulate the supply vessel fleet and inspection operations, while an RBI model assesses the risk of failure of subsea assets. Variations of the variables of interest are systematically altered to find the best solution. The results show great potential to reduce costs while maintaining the structural integrity of the equipment. In parallel, the model may provide interesting information on optimal fleet size, chartering contract types, and the best inspection strategy for a specific offshore field. The coupling of RBI with logistic optimization seems promising to improve the efficiency of inspection and monitoring of O&G subsea assets in Brazil.
Almansa, María José Legaz; Montalvo, Maria Paz ; Cepeda, Maricruz Aurelia Fun Sang ; Ruiz, Juan; and Caprace, Jean-David , SOBENA (2022)
29th International Congress on Waterborne Transportation, Shipbuilding and Offshore Constructions . Volume 29, Brazil. SOBENA, SOBENA.
Currently, engineering designers are working to automate the design process. Using tools to support decision making, engineers can explore a wider range of options and reduce the time to an initial design. An area which is prominent in the literature is the dimensioning of ships in the early stages. This is a complex part of naval design. Because shipbuilding is a competitive market, the construction cost of a ship is a vital part of the sale price. The objective of this work is to assess the main dimensions of various types of merchant ships by minimizing construction costs with computational methods. The difficulty presented by ship dimensioning is that it is a restricted optimization system of a non-linear type. In this work, to solve it, two mathematical methods have been applied that adapt to this type of problem; the genetic algorithm (GA) method and the sequential quadratic programming (SQP) method. A practical application of the calculation of the main dimensions of a new ship to be designed through the utilization of the procedures described in this work. The advantages of using genetic algorithms for ship dimensions are shown. A graphical interface has been developed to solve the problem of optimal dimensioning of a ship using AppDesigner integrated with Matlab.
Lustosa, Geovanna; Prado, Victor; Lauande, Augusto; Vásquez, Jamil Alejandro Fernández; Souza, Matheus Rodrigues de; Ignez, Bruno Pinto; Silva, Bruno; Paúra, Lidia; and Caprace, Jean-David , SOBENA (2022)
29th International Congress on Waterborne Transportation, Shipbuilding and Offshore Constructions . Volume 29. SOBENA, SOBENA.
O presente resumo tem como objetivo apresentar inovações no desenvolvimento de veículos autônomos subaquáticos (AUVs) dentro das universidades brasileiras. Apesar do início da construção desses veículos datar de 1980, até 2016 ainda não havia projeto de construção de AUVs dentro de universidades da América do Sul, fato que motivou a criação da UFRJ Nautilus, uma equipe de estudantes que visa o desenvolvimento de AUVs voltados para a competição na RoboSub. Atualmente, a equipe conta com três AUVs, sendo o primeiro projeto já aposentado e tendo advindo de modificações feitas em um ROV, o segundo já semifinalista nomeado BrHue que competiu pela primeira vez em 2018, e por último o já premiado projeto Lua que apesar de estar em fase de construção já compete desde 2021 e recebeu a melhor premiação da equipe até o momento como 3° lugar no quesito paper técnico. Nossos AUVs contam com um computador de bordo embarcado, um sistema de inteligência artificial, uma máquina de estados, um backplane, uma rede interna de comunicação, estando tudo dentro de uma estrutura modular e estanque com um sistema de conectores submarinos para controle dos propulsores e atuadores e aquisição de dados dos sensores. Com as últimas competições online também contamos com os modelos tanto do robô quanto da piscina de provas da marinha americana em um simulador especializado para submetermos todos os parâmetros de construção do projeto junto com os códigos e podermos ver como ele se comporta em um ambiente quase real. Esse tipo de simulação também permitiu que a RoboSub acontecesse durante a pandemia com a submissão dos resultados do robô no ambiente virtual. Assim, a equipe vem ao longo dos anos não só representando o Brasil e a UFRJ na maior competição de AUVs do mundo como disseminando o conhecimento envolvido no projeto dentro da faculdade e comunidade acadêmica e também formando melhores alunos com maior conhecimento técnico e prático no desenvolvimento de um projeto.
Oliveira, Giovanna; Lima, Ariel; Martins, Paula ; and Caprace, Jean David , SOBENA (2022)
29th International Congress on Waterborne Transportation, Shipbuilding and Offshore Constructions . Volume 29, SOBENA.
A invenção dos motores a gasolina e diesel possibilitaram o início de um grande marco histórico: A Era do Petróleo, e com isso, a necessidade de inovações para a captação desses produtos fez com que embarcações do tipo PLSV se tornassem primordiais para a perpetuação do sucesso. Essas embarcações de apoio marítimo offshore, são responsáveis pelo lançamento de dutos submarinos de petróleo e gás. Esse tipo de embarcação surgiu devido à expansão mundial do mercado de exploração de petróleo. No Brasil, por exemplo, as descobertas de novos poços de petróleo e gás geraram uma demanda de novas plataformas e, com isso, houve um crescimento na demanda por embarcações que realizem operações adequadas a essas situações. O objetivo do PLSV, portanto, visa a interligação dos poços para o escoamento de óleo e gás para as plataformas na superfície. Em primeira análise, é importante destacar a operacionalidade dessas embarcações. Assim, são definidas em três metodologias para a colocação dos tubos: a primeira delas é a “S-lay”, sendo a mais usada para colocar tubos flexíveis em águas rasas com custos mais baixos em velocidade relativamente rápida; a segunda metodologia empregada é a “J-lay”, sendo a mais utilizada para dutos rígidos; e por último, tem-se a “Reel-lay”, o qual tem um serviço em tempo mais acelerado, de até 4 km/h, porém possui limitação quanto ao tamanho dos dutos lançados. Sob essa ótica, a complexidade da interligação dos dutos submarinos aumenta com a profundidade, além da necessidade de uma produção a curto prazo. A partir desses dois pontos, pode-se ressaltar que inúmeras incertezas apareçam durante o processo, acarretando, assim, em ociosidade nas embarcações ou postergações na produção de petróleo, que podem resultar em prejuízos. Nesse contexto, outro aspecto que cresce ao longo do tempo é a descarbonização do meio marítimo, pois com as emissões dos gases de efeito estufa, há um agravamento no meio ambiente, assim como na saúde humana. Dessa forma, a necessidade de estabelecer metas que conduzam as embarcações para um estado de carbono neutro e possivelmente um Net Zero no futuro se potencializa e demonstra a urgência de medidas de mitigação. Sob essa análise, surge o grande desafio: encontrar um equilíbrio entre economia e meio ambiente, adequando com cada tipo de embarcação estudada. Destarte, as embarcações do tipo PLSV permitem uma continuidade das operações das zonas de perfuração do alto-mar até as usinas de processamento e é uma peça indispensável na totalidade e efetivação das operações de petróleo em alto-mar. Porém, deve-se estabelecer medidas de mitigações dos efeitos estufa para alcançar as metas da IMO. É válido destacar a importância de inovações para uma otimização cada vez maior para suprir as demandas do mercado marítimo, pois com as constantes mudanças no meio tecnológico, a possibilidade de melhoria maximiza a eficiência e garante a perpetuação de êxito na captação de óleo e gás, e nesse sentido, os combustíveis alternativos ganham cada vez mais destaque.
Pitta, Alexandre de Jesus; Guimarães, Gabriel Batista; Cozini, Patricia Oliveira; and Caprace, Jean-David , SOBENA (2022)
29th International Congress on Waterborne Transportation, Shipbuilding and Offshore Constructions . Volume 29. SOBENA, SOBENA.
Os FPSO’s (sigla em inglês para Floating Production Storage and Offloading) vem tomando o lugar das plataformas convencionais na indústria petroleira. Entre as razões para isso, podemos mencionar o baixo custo de produção, uma maior capacidade de armazenamento e, sobretudo, a possibilidade de exploração de poços mais distantes da costa que normalmente apresentam a inviabilidade econômica da instalação de tubos que transportam o produto. O presente trabalho pretende realizar uma revisão do estado da arte acerca das inovações tecnológicas que permitem a otimização de diferentes setores de um FPSO. Os estudos foram realizados com base em softwares como o Aspen HYSYS®, que simula a planta de processo da embarcação, bem como a utilização de técnicas como o Algoritmo Genético e o Método dos Elementos Finitos. Em um dos artigos revisados foi feita uma análise de otimização da planta de processo, o que permitiu uma redução do consumo de energia e, consequentemente, do combustível e das emissões de gases do efeito estufa. Os demais estudos revisados aqui, em suma, seguem o mesmo princípio de utilizar tecnologia de ponta para otimizar processos e/ou estruturas do FPSO, assim proporcionando resultados benéficos em diversas áreas como meio ambiente e economia.
Ramos, Ramiro Fernandes; Strauhs, Mikael; Martins Neto, Severino Virgínio; de Lira, Antonio Rafael Paulino; Cepeda, Maricruz Aurelia Fun Sang; de Carvalho, Luiz Felipe Guaycuru; Moita, João Vitor Marques de Oliveira; Caprace, Jean-David , SOBENA (2021)
Proceedings of 12th International Seminar on Inland Waterways and Waterborne Transportation . Volume 12, Rio de Janeiro. SOBENA, SOBENA.
Computational vision is the ability of a machine to process images or videos. Many technologies are used to develop this ability. Deep learning is a technique inside the machine learning area, where a neural network is used but with a more profound complexity than the usual neural networks. Deep learning is changing the scenario for computational vision since it is more efficient than the others and is becoming more popular. Given this popularity, deep learning for computational vision is applied for multiple fields of study. In the maritime industry, this technique is being used by different researchers to help them identify and classify ships automatically through images and videos. Also, it is being applied in subsea inspections to simplify the task of detecting objects in the seabed. This paper reviews the current state of the art of using deep learning techniques for computational vision within the Maritime Industry. The target for each study is analyzed. A comparison of the dataset used and the type of deep learning are made. The most common target is to identify ships using surveillance cameras or satellite images. Subsea equipment, corals, underwater mines, marine organisms, and oil spills are other targets. The most used deep learning technique is the convolutional networks. This result is not only observed in the maritime domain but for any computational vision problem. The neighbors' data influence the convolutional network result, and the pixel of an image is very similar to its neighbor pixel, evidencing its advantage. There are at least ten different types of convolutional networks being used in the reviewed papers, making it clear that there is space for innovation in this matter. This review and comparison can help future research, giving information on which deep learning technique to choose and how to evaluate its target.
Assis, Luiz Felipe; Bezerra, Franklin Sandino Machado , SOBENA (2021)
Proceedings of 12th International Seminar on Inland Waterways and Waterborne Transportation . Volume 12, Rio de Janeiro. SOBENA, SOBENA.
Preocupações alarmantes relacionadas às mudanças climáticas provocadas pelo aquecimento global têm pressionado as autoridades mundiais a adotar regulamentações limitando as emissões de gases de efeito estufa. O setor marítimo é responsável por 2-3% das emissões de CO2, 4-9% do SOx e 10-15% NOx. No início da última década, a Organização Marítima Internacional (IMO) estabeleceu áreas de controles de emissão em águas costeiras na Europa, América do Norte e Ásia, nas quais, a partir de 2020 só podem ser utilizados combustíveis com teor de enxofre abaixo de 0,1% e, fora destas áreas, apenas 0,5% é permitido. Em 2018, foi estabelecido o objetivo de reduzir em 50% as emissões de CO2 até 2050 se comparado aos níveis de emissões de 2008. Para atingir tais objetivos, faz-se necessário que parte da frota mundial venha a substituir o bunker por outros combustíveis livres de emissões de CO2. Nesse sentido, muitos estudos vêm apontando a amônia como a principal solução. Neste estudo, com base em uma ampla pesquisa bibliográfica, foram analisados aspectos relacionados à produção da amônia livre de emissões de CO2. Com tecnologias já disponíveis, a amônia azul, produzida com captura de carbono CCS, e a amônia verde, produzida via eletrólise, se mostram soluções tecnicamente viáveis. Foram analisados possíveis impactos ambientais no ciclo do nitrogênio global, assim como vantagens e desvantagens da adoção desse novo combustível. Foram também analisados os aspectos operacionais relacionados com o emprego da amônia a bordo como combustível no que tange: as regulamentações vigentes em 2021; toxidade e segurança a bordo; corrosividade e seleção de material para equipamentos em contato direto com a amônia; estratégias para a combustão da amônia em motores a combustão interna; sistemas auxiliares necessários para o suprimento de amônia ao motor de combustão principal e tratamento dos gases de exaustão. Considerando-se o estágio atual, pode-se concluir que utilização da amônia a bordo é tecnicamente viável, bem como, verificou-se que a cadeia global de produção da amônia apresenta 20-25% de capacidade ociosa, sendo capaz de atender a uma demanda inicial do setor de transporte marítimo. Além disso, mais de 120 portos no mundo já possui terminais especializados em amônia, o que facilitaria a logística de distribuição e, consequentemente, uma gradual transição para o uso do combustível alternativo.
Pinheiro, Andre Ricardo; Pires Jr., Floriano; Caprace, Jean-David; Leopoldi, Maria Antonieta Parahyba , SOBENA (2021)
Proceedings of 12th International Seminar on Inland Waterways and Waterborne Transportation . Volume 12, Rio de Janeiro. SOBENA, SOBENA.
O presente artigo faz uma análise sobre o PL n° 4199/20 chamado de “Br do Mar”. É realizado uma apresentação formal do PL seguida de uma análise crítica. Para o presente estudo é adotado uma abordagem cognitiva de análise de políticas públicas proposta por Pierre Muller. Nesse contexto é definido os atores bem como seus interesses nesse Projeto. É exposto conceitos básicos que definem a rede de atores que atuam direta e indiretamente com o objetivo proposto na “Br do Mar” realizando uma conexão causal com a estrutura estrutura de custo da cabotágem. É apresentado o conflito do interesse setorial frente ao objetivo global formalizado pelo “policy maker” analisando as implicações políticas desse Projeto. Apesar da promessa ousada de diminuição do custo, e aumento de competitividade, pelo menos em temos quantitativos, o PL não apresenta uma diminuição dos custos significativos carecendo de uma análise custo-benefício mais abrangente, pois diversos aspectos importantes foram excluídos do projeto, seja por interesse setorial, ou por não legislação do ente federal.
Martins, Vinicius; Ramos, Ramiro Fernandes; Cepeda, Maricruz Aurelia Fun Sang; Caprace, Jean-David , SOBENA (2021)
Proceedings of 12th International Seminar on Inland Waterways and Waterborne Transportation . Volume 12, Rio de Janeiro. SOBENA, SOBENA.
O comércio marítimo desempenha um papel crucial na economia global e os recentes desenvolvimentos tecnológicos aceleraram a logística marítima. No entanto, esse aumento impactou o desempenho portuário, levando ao congestionamento em algumas regiões e distorcendo o fluxo da logística marítima. Poucos estudos empregando dados AIS exploraram o congestionamento do tráfego marítimo, portanto, é necessário desenvolver um sistema que torne as métricas dos portos mais acessíveis. Este trabalho emprega uma metodologia para analisar o nível de congestionamento portuário do Rio de Janeiro. Três algoritmos foram desenvolvidos utilizando dados do Sistema de Identificação Automática (AIS) para identificar a geolocation area, convex hull area, e average vessels proximity. Esses algoritmos foram empregados para calcular os Indicadores de Congestionamento Portuário (PCIs): spatial concentration, spatial density, average service time e técnicas de machine learning foram utilizadas para extrair conhecimento do banco de dados. Como resultado, esse processo identificou os períodos em que o porto está mais congestionado e os centroides desses clusters podem ser usados para prever os níveis de congestionamento. Esses indicadores fornecem recursos para uma melhor gestão e podem motivar ações como a redistribuição dos locais de carga e descarga dos navios e a melhoria do desempenho portuário.
de Carvalho, Luiz Felipe Guaycuru; Ramos, Ramiro Fernandes; Cepeda, Maricruz Aurelia Fun Sang; Caprace, Jean-David , SOBENA (2021)
Proceedings of 12th International Seminar on Inland Waterways and Waterborne Transportation . Volume 12, Rio de Janeiro. SOBENA, SOBENA.
The world's ship fleet is responsible for about 2.7% of greenhouse gas emissions (GHG). The International Maritime Organization (IMO) has fixed the 2050 target for the GHG reduction from marine transportation being half the GHG emission from 2008. The current most applied and documented technology to reach this objective is known as “slow steaming”, which consists of reducing emissions by voluntarily reducing the cruise speed of vessels. However, research and developments are still lacking to achieve the goals of maritime decarbonization established by the IMO. Both energy-saving devices (ESD) and environmentally friendly fuels are two promising solutions. This paper reviews the different wind power propulsion technologies, a kind of ESD, applicable to international cargo vessels. The technologies currently available and already in use, as well as concepts still in preliminary stages of development, are compared using emission, control, and operational criteria. Different routes and wind regimes, including the lacustrine and fluvial environment, are considered in the study. The preliminary results point to a drastic GHG reduction reaching a range between 5 to 30% for large cargo ships. Although still very incipient, the wind propulsion technology applied to large cargo vessels is becoming attractive, i.e. one of the largest mineral carriers (VALEMAX) has been recently equipped with 5 Flettner rotors. The perspectives are encouraging and the results presented here intend to position the technologies in a context of a future broad and worldwide application.
Fun Sang Cepeda, Maricruz A.; Monteiro, Gabriel P.; Moita, João V. M. de Oliveira; Assis, Luiz Felipe; Caprace, Jean-David (2020)
Proceeding of the VI International Ship Design & Naval Engineering Congress (CIDIN) and XXVI Pan-American Congress of Naval Engineering, Maritime Transportation and Port Engineering (COPINAVAL) , Cartagena, Colombia. Instituto Panamericano de Ingeniería Naval and COTECMAR, Springer, Cham.
Automatic Identification System (AIS) data records a huge quantity of information regarding the safety and security of ships and port facilities in the international maritime transport sector. However, this big database is not only useful for the security of ships operations and port facilities. It can also be helpful for other important functions in maritime traffic such as reducing environmental impacts, improve logistics and analyses compliance with current International Maritime Organization (IMO) regulations. This study develops an analytical approach to quantify the impacts of ship emissions in the Guanabara Bay of Rio de Janeiro (Brazil) using the AIS database as well as the life cycle assessment (LCA) tool. The paper describes a method in two steps. First, the inventory of ship emissions is evaluated and geolocated with AIS data through the assessment of fuel consumption calculated for each individual vessel. Then, the impact of the emissions is assessed with the ReCiPe LCA method that translates emissions into a limited number of environmental impact scores by means of so-called characterization factors. The results show that the proposed methodology is efficient to estimate the environmental impact of ship emissions over the Rio de Janeiro Port area. We suggest that quantifying the number of emissions from ships in order to fulfill IMO regulations and reduce the health impacts of people who are living in surrounding areas of high maritime traffic is important for decision-makers and for the maritime authorities to improve their strategies.
Moita, João Vitor Marques de Oliveira; Ramos, Ramiro Fernandes; Nogueira, Luisa; Drummond, Igor; Rodrigues, Geraldo Pinto; Lourenço, Marcelo Igor; Caprace, J.-D. (2020)
Proceedings of Rio Oil & Gas Expo and Conference 2020 , Rio de Janeiro. IBP, IBP.
The use of deep learning in subsea inspection by Autonomous Underwater Vehicles (AUV) is a field that has a non-explored potential. Even though these vehicles operations are already automatized, their image analysis is still done manually, being a tedious job, passive of errors by distraction or exhaustion of the operator. This work develops a deep neural network to detect and locate events on subsea images captured by an AUV campaign. Typical subsea events consist of subsea pipeline track lines, pipeline crossing, presence of subsea valves and manifolds, presence of sacrificial anodes, etc. The final purpose of this study is to reduce the operational time and costs of those inspections by an automatic mapping of the sea floor. The results show the accuracy of the detection and the categorization as well as the efficiency of the geo-localization on a case study of mapping the crossing points (events) between several subsea pipelines.
Vieira, Joao Henrique; Rossi, Fabio Macedo; Ramos, Ramiro Fernande-s; Alves, Sarah Menezes; Caprace, Jean David , SOBENA (2020)
Proceedings of 28th International Congress on Waterborne Transportation, Shipbuilding and Offshore Constructions Proceedings , Rio de Janeiro. SOBENA, SOBENA.
In recent years, the shipping of containers has grown worldwide, as well as the size of container vessels, following the globalization process. According to UNCTAD Statistics (2019), the global container shipping throughput increased from 45 Million TEUs handled in 1996 to 150 Million TEUs handled in 2018. Although, the seaport operational performance measurement is still restrictive to data providers and conservative on refining KPIs from different operational perspectives. The purpose of this article is to develop an analytical process approach of operational indicators of container throughputs and handling performance, deployed by a shipping line service at an Eastern South America and European round trip voyage. The math model applied in this paper pursues key features and metrics that influence the container liner services scheduling. Accordingly, the methodology framework was designed to explore critical berth productivity factors and to correlate capacity efficiency variables. Furthermore, this research explored process benchmarking analysis on berth productivity from terminals and vessel operators' perspectives. It was clarified by KPIs analog to the line service attendance, such as the aggregated quay cranes handling a throughput of 600,722 TEUs in 2018 in contrast to vessel shipping throughput of 525,840 TEUs for the same period. Also, this research played attention to the optimization of port calls and data standardization.
Silva, Marcos Antonio de Souza; Vinzon, Susana B.; Guerra, Josefa Varela; Caprace, J.-D. (2020)
Proceedings of 28th International Congress on Waterborne Transportation, Shipbuilding and Offshore Constructions Proceedings , Rio de Janeiro. SOBENA, SOBENA.
Simulador de navegação é um sistema que reproduz em terra, sob determinadas condições pré-definidas, algumas das atividades executadas a bordo. Algumas teorias são descritas na literatura para aplicação de simuladores na avaliação da segurança em canais de navegação. No entanto, estes trabalhos não abordam a utilização de dados de vento e corrente aplicados em simuladores no modo fast -time, que, por executarem as simulações de forma mais rápida, permitem a análise do canal como um todo, para cada combinação de vento e corrente. Este trabalho teve como objetivo desenvolver um método probabilístico para análise de segurança da navegação ao longo de um canal, utilizando simulador no modo fast-time, combinando dados de vento e corrente. As simulações realizadas tiveram como cenário o canal de acesso ao terminal da Ilha Guaíba/RJ. Os dados obtidos foram classificados quanto a intensidade e combinados em cenários para aplicação no simulador. Para a análise probabilística foram consideradas as teorias desenvolvidas por Briggs et al (2003) e Gucma et al (2018). Foram realizadas 399 simulações no simulador do CASNAV. O canal de entrada, em termos de dimensões horizontais, apresentou grau de segurança adequado. No entanto, as seções 96, 101 e 128 do canal apresentaram riscos relevantes sobretudo nas combinações de dados ambientais de categorias severa e moderada. A metodologia utilizada demonstrou ser eficiente na análise de segurança da navegação de canais de entrada empregando diversos cenários ambientais em simuladores no modo fast-time.
Alcantara, Felipe Jorge; de Souza, Marcelo Igor Lourenco; Pierret, Stephane; Caprace, J.-D. , SOBENA (2020)
Proceedings of 28th International Congress on Waterborne Transportation, Shipbuilding and Offshore Constructions Proceedings , Rio de Janeiro. SOBENA, SOBENA.
Wind energy has already been broadly explored onshore and, in the last years, it has begun to move offshore. However, moving offshore leads to more costs with the construction, installation, maintenance, and decommissioning of the wind turbines. Therefore, this paper presents a methodology to optimize the structure of a monopile offshore wind turbine (OWT) in the preliminary stages of design, aiming at minimizing the welding time, structural weight, and, as a result, the construction costs. The constraints regard the tower top rotation and displacement, structural integrity under ultimate loads, and resonance check.
Strauhs, Mikael Proença; de Lira, Antonio Rafael Paulino; Ramos, Ramiro Fernandes; Moita, João Vitor Marques de Oliveira; Martins Neto, Severino Virgínio; Caprace, J.-D. , SOBENA (2020)
Proceedings of 28th International Congress on Waterborne Transportation, Shipbuilding and Offshore Constructions Proceedings , Rio de Janeiro. SOBENA, SOBENA.
The task of detecting a ship is relevant for a variety of applications in both military and civilian fields, from maritime traffic surveillance to sea pollution monitoring. Despite the recent significant attention, deep learning-based object detection algorithms have received, they are still rarely applied in the detection of ships. Expectedly, we see even fewer applications when the goal is to detect specific ship classes, although those could deliver extra valuable information. In this work, we build a ship detection algorithm capable of distinguishing six common ship types: ore carrier, bulk cargo carrier, general cargo ship, container ship, fishing boat, and passenger ship. To achieve this objective, we firstly built a deep convolutional neural network in python, taking advantage of the TensorFlow framework. Secondly, we analyzed our model’s ability to generalize on a new set of images, apart from the training and testing sets. The results showed that our proposed model is close to state-of-the-art performance since it was able to perform well on the test set - mAP = 97.62%. There is still room for improvement on the model robustness, associated primarily with possible training set limitations. In practice, this paper will contribute to the advance of research and applications on ship detection.
Heckler, Otavio; Souza, Jeferson Avila; Caprace, J.-D.; Marques, C. H. , SOBENA (2020)
Proceedings of 28th International Congress on Waterborne Transportation, Shipbuilding and Offshore Constructions Proceedings , Rio de Janeiro. SOBENA, SOBENA.
Na navegação em hidrovias, a preocupação com as emissões é ainda maior do que em relação a navegação marítima porque os navios operam perto de áreas urbanas ou em reservas naturais, tornando a necessidade de proporcionar uma navegação ecológica de importância primordial. Nesse contexto, uma análise da potência requerida da embarcação é necessária e com esse propósito foi realizado o estudo de uma balsa. O principal objetivo desse estudo foi analisar a resistência ao avanço no casco da balsa em escala real. Dessa forma foi desenvolvido um modelo computacional para estimar a resistência ao avanço da balsa. Esse modelo foi baseado no método VOF (volume of fluid) para escoamentos multifásicos (água e ar) a partir do solver interFoam utilizando o programa OpenFOAM. O solver resolve as equações de Navier-Stokes para dois fluidos isotérmicos, imiscíveis e incompressíveis. A abordagem do escoamento turbulento foi realizada com a modelagem RANS (Reynolds-Average-Navier-Stokes) com o modelo SST K-ω. Após validar o modelo numérico com uma referência da literatura de um ensaio experimental, a curva velocidade-resistência obtida é comparada com a proveniente do método Holtrop para quantificar os desvios entre essas abordagens. Por fim, para aproximar os resultados fornecidos por Holtrop, um valor para o coeficiente de área no plano da água é recomendado, visto que o valor unitário resulta em resistência infinita.
Martins, Vinícius Barreto; Ramos, Ramiro Fernandes; Cepeda, Maricruz Fun Sang; Caprace, J.-D. , SOBENA (2020)
Proceedings of 28th International Congress on Waterborne Transportation, Shipbuilding and Offshore Constructions Proceedings , Rio de Janeiro. SOBENA, SOBENA.
Maritime trade plays a key role in the global economy and recent technological developments have accelerated maritime logistics. The managers and authorities have increasingly been under pressure to improve port performance by ensuring that the port provides services on an internationally competitive basis. However, this increase in maritime trade has an impact on ports performance, leading to port congestion in some regions and distorting the smooth flow of maritime logistics. Port congestion is an important issue from an economic and efficiency point of view because it results, not only, in longer waiting times and low service levels for vessels, but it also contributes to the decrease in competitiveness and demand. Few studies using AIS data has explored marine traffic congestion, there are still significant research gaps yet to be filled, hence the development of a system that makes metrics on ports more accessible is needed. This work employs an innovative methodology to analyze the port congestion level on the port of Rio de Janeiro. From the Automatic Identification System (AIS) data, three algorithms were used to find the convex hull area, the geolocation area, and the average vessel proximity. These algorithms were used to calculate the Port Congestion Indicators (PCIs): i) Spatial Concentration; ii) Spatial Density; iii) Average Service Time. Then, Machine Learning techniques were employed to cluster these indicators into three color-coded (blue, yellow, and purple), corresponding to low, medium, and high congestion levels. As a result, this process identified the periods when the port is most congested and the centroids of these clusters can be used to predict the behavior of port congestion levels. These indicators provide resources for better management and can motivate actions such as the redistribution of ship loading and unloading locations, improving the port performance measurement, and helping understand the aspects that influence port congestion.
Bretas Rozo, L. F.; Assis, L. F. (2019)
Proceedings of the 6to. Congreso Internacional de Diseño e Ingeniería Naval y XXVI Congreso Panamericano de Ingeniería Naval, Transporte Marítimo e Ingeniería Portuaria, COPINAVAL 2019 , Cartagena de Indias, Colombia. IPEN, Pan-American Institute of Naval Engineering (IPEN).
Guimarães, Kelton P.; Cepeda, M. A. F. S.; Caprace, J.-D. , SOBENA (2019)
Proceedings of 11th International Seminar on Inland Waterways and Waterborne Transportation . Volume 1, Brasilia. SOBENA, SOBENA.
As a signatory to the Paris agreement, Brazil needs to look for ways to make its transport logistics more environmentally efficient in order to reduce its greenhouse gas (GHG) emissions. Note that in the academic literature there is no analysis regarding the mitigation of these emissions from the use of logistics corridors recently incorporated into the transport matrix of Mato Grosso. Therefore, this paper aims to quantify the potential mitigation of greenhouse gas emissions generated by the transportation of soybean and matogrossense corn to export through the Top-Down method. Quantify the current transport matrix emissions scenario analyzed and provide a tool for Brazilian decision makers and regulators to assess different possibilities for reducing fuel consumption and GHG emissions from more efficient logistics corridors. The results indicate that compared to 2000, Brazil has already reduced its fuel consumption by 22% and its GHG emissions by 21%. Regarding future scenarios, the target of 20% of biodiesel to fossil diesel and use of ports located in the Barcarena region is expected to reduce fuel consumption by up to 23% and GHG emissions by 22%. Finally, it is noted that compliance with the IMO standards will reduce by up to 80% of the SO2 emissions generated by the use of fuel oil in waterway transportation.
Cepeda, Maricruz Fun Sang; Kneipp, Rafaela Barros; Caprace, J.-D. (2019)
Proceedings of 11th International Seminar on Inland Waterways and Waterborne Transportation , Brasilia. SOBENA, SOBENA DOI: 10.17648/sobena-hidroviario-2019-110565.
In Brazil, the transportation of iron ore corresponds to 74% of the products handled in the Brazilian railways. One of the important centers of the production of this material is the North Brazilian region, namely the Serra dos Carajás. Iron ore is currently drained by rail, but the northern and north-eastern Brazilian zone has large waterways that could be a modal alternative. Water transport routes as a logistical alternative of rail and road modalities for the disposal of soybeans in other areas of Brazil have already been studied, but modal alternatives have not been evaluated for the transport of iron ore. The objective of this work is to develop a prototype system to evaluate the feasibility of transportation of modal alternatives of iron ore from the North region by a mathematical origin-destination model (export point), considering ore production costs, distance, and quantity demanded at the point of destination implementing Geographic Information System (GIS). The GIS provides functionalities to increase efficiency and reliability in the data analysis process. Among these functionalities the representations of real objects, support for spatial analysis, storage and reliability of information through database concepts can be distinguished. Scenarios will be evaluated to have a cost-benefit comparison of modal alternatives. The case study has as its origin the Carajás complex and as destination two export locations of the product, which are Ponta de Madeira and Belém. Actual data on the current iron ore flow in Brazil were considered. The results are providing a technical tool for decision makers comparing the efficiency of the transport alternatives.
Ramos, R. F.; Cepeda, M. A. F. S.; Moita, João V. M. de O.; Monteiro, Gabriel P.; Fiksdahlb, Olav; Caprace, J.-D. , SOBENA (2019)
Proceedings of 11th International Seminar on Inland Waterways and Waterborne Transportation . Volume 1, Brasilia. SOBENA, SOBENA.
The Santos Bay, located in Brazil, holds the largest and busiest container port in Latin America. Many cargo ships pass through this Bay every day and its safety is subject to many researches. Using the Automatic Identification System (AIS) messages sent by those ships it is possible to detect possible near-miss collisions events. This study develops an analytical approach to identify the most common cargo ship types involved in near-miss collisions in Santos Bay (Brazil) using AIS database. It will also identify the most common type of vessel conflict in this area. The model is applied to rank the severity of an encounter between two vessels based on vessel conflict ranking operator (VCRO). The vessel size and the Minimum Distance to Collision (MDTC) concept are considered in the model. The results show that the proposed methodology is adequate to identify various statistics in near-miss collisions. Containers ship is the most common type of cargo ship involved in those situations and the crossing conflict occurs with higher frequency. Understanding the parameters involved in a near-miss collision around areas of high maritime traffic is important to avoid accidents. For the future, comparisons of data between different areas are suggested.
Rossi, Fábio M.; Alves, Sarah M.; Assis, Luiz F. , SOBENA (2019)
Proceedings of 11th International Seminar on Inland Waterways and Waterborne Transportation . Volume 1, Brasilia. SOBENA, SOBENA DOI: 10.17648/sobena-hidroviario-2019-110527.
O presente trabalho consiste em uma pesquisa documental e uma análise preliminar sobre a logística do transporte hidroviário pelo eixo central do Corredor Norte, segundo maior ponto de saída de grãos do Brasil para o exterior. O objetivo do presente trabalho é reunir, analisar e consolidar dados disponíveis, por órgãos do governo e por empresas privadas, sobre a produção e as operações portuárias pelo eixo central do Corredor Norte brasileiro, visando estudar a carência desses dados para análises operacionais. Os resultados indicam que a forma de apresentação e a análise dos dados pode facilitar a compreensão de suas relações e, por consequência, o seu emprego no planejamento logístico do transporte hidroviário no âmbito do Corredor Norte.
Alves, Sarah M.; Ferreira, Bernardo C. B. da C.; Monteiro, Gabriel P.; Moita, João V. M. de O.; Gallo, Marcos; Vinzon, Susana B.; Caprace, J.-D. (2019)
Proceedings of 11th International Seminar on Inland Waterways and Waterborne Transportation . Volume 1, Brasilia. SOBENA, SOBENA DOI: 10.17648/sobena-hidroviario-2019-110562.
Brazil is the world’s second-largest soybean producer considering the last harvest 2017/2018 with a production of 117 million tons. This increases the grain outflow demand that creates a need for larger vessels with greater draft. Navigation on the Amazon River is considered critical due to the presence of fluid mud, which results in restricted depth at 11.7m. However, the current ships can’t navigate at full capacity because of the risk of running aground or damage to the hull. Considering this problem, this paper reports a case study using a marine traffic simulation program that evaluates the tidal windows of the north channel of the Amazon River in order to assess the feasibility of the navigation with greater drafts and, consequently, greater load capacity in this region. The methodology consists of a traffic simulation including tidal prediction and Squat effect to enhance cargo capacity and navigation safety. Preliminary results indicate there is a potential to increase the deadweight of the ships safely. The study proposes to create a model that assists in the decision making of the optimal tide window to navigate which will allow greater cargo transport with less possibility to ground with the bottom.
Tsumura, Shuichi; Meirelles, Eduardo V.; Callil, Victor M.; Lourenço, Marcelo Igor; Caprace, J.-D. (2019)
Proceedings of 11th International Seminar on Inland Waterways and Waterborne Transportation . Volume 1, Brasilia. SOBENA, SOBENA.
Fusion welding is a largely applied method in naval industry, which enables structural strength and watertightness between joined parts. Distinct welding processes were developed, granting various advantages as productivity, structural strength and possibility to join thicker plates. The combination of different welding processes tends to overcome some particular disadvantages of each one, as seeing in hybrid laser/GMAW welding. However, the resultant state of the welded structure becomes more complex to predict, as the possible combinations of welding parameters grows severely on hybrid welding. The purpose of the present work is to evaluate how is affected the behaviour of weld beads and welded structures when hybrid welding parameters are varied. Experimentally, a set of hybrid laser/MAG welds were performed on KD36 (NK Grade), combining different values of laser power, MAG voltage and amperage, travel speed and plate thickness. Temperature field, weld bead dimensions, hardness and residual stresses were the main collected data. For the simulations were carried two combinations of heat sources, where MAG welding was set as a double ellipsoid and laser as a double ellipsoid and a cylindrical heat source. Were observed that the heat input of each welding process influences with different weights the weld bead dimensions. For the parameters evaluated, hardness presented standard behaviour with higher values at FZ and HAZ. Therefore, these regions are more susceptible to break down when submitted to high loads. The simulations achieved a good agreement with measured residual stresses, showing that both combinations of heat sources are efficient.
Alves, S. M.; Caprace, J. D.; Ferreira, B. C. B da C.; Gallo, M.; Moita, J. V. M. O.; Monteiro, G. P.; Vinzon, S. , Marinha do Brasil - IEAPM (2019)
Proceeding of XIII Simpósio Sobre Ondas, Marés, Engenharia Oceânica e Oceanografia por Satélite (OMARSAT) . Volume 1, Arraial do Cabo, RJ, Marinha do Brasil - IEAPM.
A navegação no rio Amazonas é considerada crítica devido à presença de lama fluida, que resulta em uma profundidade restrita de 11,5m. Considerando este problema, este trabalho relata um estudo de caso utilizando um programa de simulação de tráfego marítimo que avalia as janelas de maré do canal norte do rio Amazonas para avaliar a viabilidade da navegação com maior calado e, consequentemente, maior capacidade de carga nesta região. A metodologia consiste em uma simulação de tráfego incluindo previsão de maré e efeito Squat para aumentar a capacidade de carga e a segurança na navegação. Resultados preliminares indicam que há potencial para aumentar o peso morto dos navios com segurança. O estudo propõe a criação de um modelo que auxilie na tomada de decisão da janela de maré ideal para navegação que permitirá um maior transporte de carga com uma baixa possibilidade de encalhe no fundo.
León, Alejandro Roldán; Braga, Hito; Caprace, J. D. (2019)
Proceedings of 11th International Seminar on Inland Waterways and Waterborne Transportation . Volume 1, Brasilia, Brasil. SOBENA, SOBENA.
A strong logistics chain has proven to be a key factor and a priority goal in any modern economy as it provides efficient ways to connect internally in terms of both production and people. However, inland waterways in South American countries are weak and poorly developed. A solid connectivity strategy, aiming at improving productivity and reliability, must be designed and implemented for the entire region. This involves the development of a standardization process that can be based on European, North American and specific local references. This paper intends to provide guidelines originating from a case study, which could be applicable for further studies. As a result, this paper suggests the improvement of a waterway known as “Paraguay-Paraná,” set for convoy use according to the river capacity based on specific calculations including breadth, length, and draught as well as curvature radius. The standardization process will take place in different phases within a specific timeline, and the expected outcome entails a logistics chain capable of boosting the region ́s economy in terms of increasing its load movement capacity, as well as contributing to the development of its own internal waterways classification methodology at the local level.
Guimarães, Kelton P.; Caprace, J.-D. (2019)
Proceedings of 11th International Seminar on Inland Waterways and Waterborne Transportation . Volume 1, Brasilia, Brasil. SOBENA, SOBENA.
With a large volume of public and private investments in recent years, Mato Grosso producers have been betting on the ports of Arco Norte to reduce transportation costs. There are few studies in the literature seeking to quantify this possible cost reduction and a smaller amount of work considers the influence of sea freighting and practice on the advantages obtained in domestic logistics. This paper analyzes the composition of transport costs for the main logistics corridors linking the four most important macroregions of agricultural production in Mato Grosso with the ports of Shanghai, China, and Hamburg, Germany. The results show that Arco Norte ́s ports can reduce domestic transportation costs to certain regions of the state by up to 46% and even with higher sea costs to China compared to southeastern ports, those ports located in the Barcarena (PA) region allow up to a 34% reduction in export costs to shanghai and up to 40% in export costs to Hamburg.
Cepeda, M. A. F.; Monteiro, G. P.; Moita, J. V. M. O.; Caprace, J.-D. J. E. M. (2018)
Proceeding of 17th International Conference on Computer Applications and Information Technology in the Maritime Industries . Volume 1, Rio de Janeiro.
Automatic Identification System (AIS) data stores huge quantity of information regarding the safety of ships and port facilities in the international maritime transport sector. However, this big database is not only useful for the security of ships operations and port facilities. It can also be helpful for other important functions in maritime traffic such as reducing environmental impacts. This study develops an analytical approach to quantify ship emissions in the Guanabara Bay of Rio de Janeiro (Brazil) using AIS database. The model is applied to quantify Green House Gas (GHG) emissions trough the assessment of fuel consumption calculated for each individual vessel. The results shows that the proposed methodology is efficient to estimate total ship emissions over Rio de Janeiro Port area and Guanabara Bay. We suggest that quantifying the amount of emissions from ships in order to fulfil IMO regulations and reduce the health impacts of people who are living in surrounding areas of highmaritime traffic is important for decision makers and for the maritime authorities.
Caprace, J.-D.; Souza, B. O. L. d.; Távora, G. D. S.; Monteiro, G. P.; Lourenço, M. I. (2018)
Proceeding of Rio Oil & Gas Expo and Conference 2018 , Rio de Janeiro, Brasil, Rio Oil & Gas.
Once the Brazilian mature fields are reaching the end of their live, there is a need to take decision on how efficiently perform the decommissioning of their facilities including platforms, topsides and subsea assets. Decision problems such as ranking, choice and sorting problems are often complex and most of the time, there is no one, perfect option available to suit all the criteria (technical, societal, environmental, economic, safety, etc.). The aim of this paper is to confront the comparative assessment method developed for the decommissioning program in Brent Field North Sea to a multi criteria decision analysis (MCDA) called Preference Ranking Organization METHod for Enrichment Evaluation (PROMETHEE). The results are showing important differences in their respective result. The outcome of the study shows that the comparative assessment developed in the North Sea is probably not adequately representing the complexity and the diversity of technical and environmental situations encountered in Brazil. In these terms, the development of a decision-making methodology to Brazilian decommissioning problems integrating technical, environmental, life cycle assessment, social, economic, safety, risks, as well as regulatory, licensing and legal security issues is strongly recommended.
Lazakis, I. ; Bronsart, R.; Caprace, J.-D.; Chen, Y.; Georgiev, P.; Ilnitskiy, I.; Moro, L.; Prebeg, P.; Mendonça, J. S.; Sekulski, Z.; Sicchiero, M.; Sielski, R.; Tang, W.; Toyoda, M.; Varela, J. (2018)
Volume 1: Proceedings of the 20th International Ship and Offshore Structures Congress (ISSC 2018) . Volume 1.
Concern for the synthesis of the overall design process for marine structures, and its integration with production, maintenance and repair. Particular attention shall be given to the roles and requirements of computer-based design and production, and to the utilization of information technology.
Cepeda, M.A.F.; Monteiro, G. P.; Moita, J. V. M. O.; Caprace, J.-D. J. E. M. (2018)
Proceeding of 27th International Congress on Waterborne Transportation, Shipbuilding and Offshore Constructions, SOBENA 2018 , Rio de Janeiro. SOBENA, SOBENA.
Automatic Identification System (AIS) data records huge quantity of information regarding the safety of ships and port facilities in the international maritime transport sector. However, this big database is not only useful for the security of ships operations and port facilities. It can also be helpful for other important functions in maritime traffic such as estimating possible near miss ship collisions during a long period. This study develops an analytical approach to estimate possible near miss ship collisions in the Guanabara Bay of Rio de Janeiro (Brazil) using AIS database. The model is applied to rank the severity of an encounter between two vessels based on vessel conflict ranking operator (VCRO). The vessel size and the Minimum Distance to Collision (MDTC) concept are considered in the model. The results show that the proposed methodology is adequate for ranking and prioritizing encounters between ships. We suggest that ranking the possible near miss ship collisions around areas of high maritime traffic is important for decision makers and for the maritime authorities to make statements of maritime safety in relation to collision accidents.
Rodrigues, L. de O. C. F.; Monteiro, G. P.; Caprace, J.-D. (2018)
Proceeding of 27th International Congress on Waterborne Transportation, Shipbuilding and Offshore Constructions, SOBENA 2018 , Rio de Janeiro. SOBENA, SOBENA.
O crescimento da produção e exploração de petróleo em alto mar tem elevado a utilização de risers flexíveis e rígidos. A costa brasileira é repleta de unidades flutuantes conectadas as cabeças de poços através de risers. Portanto, é de grande importância o monitoramento da integridade estrutural dos risers e dos equipamentos envolvidos no escoamento do petróleo. Esse artigo tem como objetivo de analisar os custos da logística de inspeção de estruturas submarinas através de simulações computacionais considerando a frequência de inspeção, a quantidade de RSV’s em operação e o estado de mar e suas limitações para diversos cenários possíveis. O estudo é realizado a partir de dados probabilísticos a respeito da frequência de inspeção das estruturas submarinas, a velocidade de inspeção contando com a subida e descida do ROV, os critérios de operação do navio e as incertezas do modelo quanto aos atrasos na operação de inspeção. Os resultados obtidos analisam as diferenças entre vários cenários de layout no leito marinho em relação aos custos totais, assim como a influência meteorológica no tempo total de operação de inspeção. Conclui-se que esse tipo de simulação abre precedente para melhoria e otimização dos recursos usados nessas operações.
Simões, R.U.; Freitas, A. A. M. T. de F.; Marques,C. H.; Caprace, J.-D. (2018)
Proceeding of 27th International Congress on Waterborne Transportation, Shipbuilding and Offshore Constructions, SOBENA 2018 , Rio de Janeiro. SOBENA, SOBENA.
Voyage optimization in maritime transportation is essential to ensure good conditions of the operation – such comfort of the crew, reduce time of voyage and to maintain the efficiency and sustainability in the way to ensure cost competitiveness of ship operations. The constant need to maximize profit motivates even more developments and improvements in time organization and travel optimization systems. In fact, these technologies can lead to avoiding heavy sea conditions and to a significant reduction in travel time, fuel consumption and Green House Gas emissions. This work presents travel optimization schedules based on the Dijkstra algorithm and on Kwon’s added resistance modelling. Supported in the vessel’s movement and stochastic weather conditions, the forecast model evaluates the voyage according to different objectives: to reach the port of destination with the minimum travel time, to spend the least amount of fuel, to travel in the lowest conditions of Beaufort – in the best sea conditions - and to travel with the minimum head sea – the condition which the waves find the ship with less angulation relative to its surge movement. Therefore, the optimal route is obtained by considering both voluntary and involuntary sailing speed reduction. By utilizing a decision support tool, the ship’s crew may select the optimum route according to their objectives. The validation of the model is performed by comparing the results obtained with established commercial routes. It is then possible to compare, by the means of knowing the vessel’s and main engine characteristics, the amount of fuel consumed on the travel time for the determined routes. Work that opens the way for the consideration of greenhouse emissions.
Ramos, R. F; Caprace, J.-D. (2018)
Proceeding of 27th International Congress on Waterborne Transportation, Shipbuilding and Offshore Constructions, SOBENA 2018 , Rio de Janeiro. SOBENA, SOBENA.
Mooring is a common operation carried out by ships when they are moored in ports. With the growth of the ship’s main dimensions and the growth of their sail area, the external forces that are supported by the mooring is also growing. To ensure that a ship will support a given wind, the responsible for the mooring, in some cases, uses too many hawsers. This attitude implies in an overuse of resources and time. It is possible, using methods that integrate the mechanical mooring problem, to calculate the max-imum wind speed a given mooring configuration can withstand. The present paper demonstrates a method for calculating this speed. After the presentation of this method an analysis is done, using one vessel and one pier, both theoretical. This analysis, made through calculation with the method, observes the influence of the transversal hawsers on the maximum wind speed supported by the ship. The results show that it is possible to increase wind resistance by up to 44% with the proposed modifications. It is concluded that there are other ways to increase wind resistance without adding extra hawsers to the ship.
Schachter, R. D.; Gomes Jr., R. S. (2018)
Proceeding of 27th International Congress on Waterborne Transportation, Shipbuilding and Offshore Constructions, SOBENA 2018 . SOBENA, SOBENA.
This work presents the development of an Excel computational tool to make the necessary calculations of the preliminary structural design of Offshore Support Vessels, applying the rules of the American Bureau of Shipping Classification Society for vessels constructed of steel. The philosophy of this development was to streamline the structural calculation process in the preliminary design, from several days to a few hours, without loss of precision, based on the main characteristics of the vessel and some structural characteristics, on the user's prescription of the cave, type of steel and manufacturer, the program automatically calculates all the rules, displays all plate thicknesses calculated and adopted by commercial table and defines which reinforcing elements need to be sized. The user must then dimension the structural elements by providing the profile type, thickness and height of the web and thickness and length of the flange, such as: bottom, double bottom, side, double sided, deck and bulkhead stiffeners. The program not only verifies that the values ​​of the structural elements are in agreement with the values ​​required by the classification society at all times, but also it shows the design of the master section of the boat, that modifies to each decision of the user. In addition, the program checks the overall structural strength by calculating the steel area, section module and moment of inertia of the vessel beam and compares these values ​​with the minimum rule values ​​and analyzes whether the vessel will have longitudinal strength. Based on the master section of the ship, the sectional area curve and the position of the transverse bulkheads, the program estimates the steel weight and center of gravity of the structure. At the end, the user can generate a detailed report containing all the information generated by the program as well as the calculation memory. An example application is displayed.
Roldan, A.; de Moraes, H. B. ; Caprace, J.-D. (2018)
Proceeding of 27th International Congress on Waterborne Transportation, Shipbuilding and Offshore Constructions, SOBENA 2018 , Rio de Janeiro. SOBENA, SOBENA.
This research paper looks at some of the main elements to consider during an oil spill in open or restricted waters, focusing on the emergency first response, and the most suitable equipment available in the market. The first section reviews global figures of oil spills, the international legislation and criteria for claiming compensation, and the marine effects of an oil spill from different angles. The paper also explains how oil behavior, exposure time, and available resources are the parameters needed to establish the most time-efficient and cost-effective response strategy. Lastly, resorting to a comparative analysis, it concludes that specialized oil-spill vessels have proven to add significant value in responding to emergencies at sea and mitigating environmental damages.
Moraes, A. C.; Moita, J. V. M. O.; Caprace, J.-D. (2018)
Proceeding of 27th International Congress on Waterborne Transportation, Shipbuilding and Offshore Constructions, SOBENA 2018 , Rio de Janeiro. SOBENA, SOBENA.
The essence of logistics operations is complex by nature. Upstream logistics is constantly challenged to maintain and even increase profitability at oil exploration and production (E&P) system, where production costs are impressive. Since there are high risks involved, the research field around E&P systems is benefic to assure system performance. This paper addressed a simulation model for fleet design optimization in E&P logistics. The model regards deck cargo transportation between port and offshore unit, realized by platform support vessels. The simulation was developed in software of discrete-event environment for process flow analysis. This system was parameterized under the influence of stochastic parameters as demand, weather conditions and charter prices, by the application of probability distribution functions. The results present an effective tool for fleet design estimation, with total cost and operation data appended.
Silvino, V. R. G.; Assis, L. F. (2018)
Proceeding of 27th International Congress on Waterborne Transportation, Shipbuilding and Offshore Constructions, SOBENA 2018 , Rio de Janeiro. SOBENA, SOBENA.
O presente trabalho tem como objetivo avaliar a inserção do Porto do Açu (RJ) como porto concentrador de carga conteinerizada. São considerados diferentes cenários de serviços na rota ligando a Costa Leste da América do Sul e o Extremo Oriente (SAEC/ASIA), tendo em vista os custos de transporte da carga conteinerizada com a utilização de navios porta-contêiner de grande capacidade. Os custos por TEU obtidos para as novas configurações foram comparados com os praticados nos serviços regulares atuais. A análise mostrou a viabilidade da inserção de um novo sistema portuário na matriz de transporte de contêineres na costa brasileira, com a redução de portos escalados no Brasil e integração ao sistema de cabotagem já existente.
Schachter, R. D.; de Oliveira, P. V. S. (2018)
Proceeding of 27th International Congress on Waterborne Transportation, Shipbuilding and Offshore Constructions, SOBENA 2018 , Rio de Janeiro. SOBENA, SOBENA.
This work presents a computational tool for the conceptual and preliminary design of vessels, for calculations of hydrostatic characteristics, stability intact, easy to use and fast application, from the form represented by beacons. This code applies to vessels of various types, including monohulls and multihulls. The software integrates a computational system that contains multidisciplinary design modules, such as the generation of the shape of the hull interacting with a simplified general arrangement with features of drag and drop of objects, structural design and compartmentalization, as well as dynamic balance routines (support, drag and dynamic trim), propulsion and wave behavior. The features of this program include graphical and numerical results for screen viewing and printing of Hydrostatic and Cross Curves and Tables, Intact Stability Curves, Loading and Prescription Conditions, and Stability Criteria analysis in an environment that integrates system files. The Intact Stability code comprises a menu that allows the user to select preprogrammed stability criteria with modifiable default values ​​such as area criteria, passenger or weight accumulation on one edge, high-speed turn maneuver, combined wind with balance, allowing the choice of all required values ​​such as number and weight of passengers, arms, speeds, wind speed, application points, etc., which combined by the user allows the composition of almost any criterion of stability intact. The methodology used for hydrostatic calculations is applied using the hull beacons, a single system file. Although this program is not a form-definition routine, as the calculations are done with B-splines, in a method developed for the interpolation of the coordinates of the beacons, it is possible to create intermediate beacons to the existing ones, allowing greater precision of a simple file of input. The numerical results were compared in detail with the results of Maxsurf Hydromax (or Stability) and Freeship, in an analysis that shows the differences between these three programs and that it provides reasonable and accurate results.
Fiasca, R. B., Assis, L. F., and Pires Jr., F. C. M. , Carlos Guedes Soares, Ângelo P. Teixeira (2018)
Proceedings of the 17th International Congress of the International Maritime Association of the Mediterranean (IMAM 2017) , Lisbon, Portugal, Taylor & Francis Group.
The article presents an econometric analysis to test the hypothesis that the builder’s country influences the second hand ship value. The analysis is based on econometric modelling of second hand ship prices, having, as regressors, deadweight, age, indexes of earnings and newbuilding prices, LIBOR, and dummy variables representing the building country or region. Models specific for tankers, bulk carriers and containerships were estimated. The analysis has evidenced that, in general, the effect of the origin of the ship on the second hand price may be statistically significant.
Rigo, P.; Bayatfar, A.; Buldgen, L., Pire, T.; Echeverry, S. ; Caprace , J.-D. (2017)
Proceeding of 5th International Congress for Ship Design and Naval Engineering . Cotecmar.
Paz, P. A.; Caprace, J.-D.; Cajaiba, J. F.; Netto, T. A. (2017)
ASME 2017 36th International Conference on Ocean, Offshore and Arctic Engineering . Volume 5, Trondheim. Ocean, Offshore and Arctic Engineering Division, ASME.
Scaling problems in oil production happen frequently. There are chemical and mechanical treatments to fight with this problem. Knowing if they will happen under particular circumstances of temperature and pressure is the best way to avoid or to control their apparition. This paper shows the most important characteristics that improve the calcium carbonate scaling accumulation in pipelines in order to understand how kinetic and thermodynamic characteristics affects the scaling process. Monitoring the scaling process using the Saturation Index was considered a method for scaling solutions, this method uses characteristics as solution pH, temperature, ion concentrations, among others. The influence that temperature and initial ion concentration have over the solution pH of the scaling system was studied using an experimental test in a batch reactor, this allows to follow the scaling process in real time through pH changes. The prediction of calcium carbonate scaling process represents another objective in this work. Numerical analysis based on artificial intelligence as Multi Layer Perceptron and Probabilistic Neural Network were used. A good learning process and a good prediction model for the ANN methods was shown when the experimental SI and predicted SI were compared. It was possible to confirm the accuracy of the ANN methods using external experimental tests.
Cepeda, M. A. F.; Simoes, R. U.; Moita, J. V. M. O.; Assis, L. F.; Caprace, J.-D. J. E. M. , Bertram, V. (2017)
Proceedings of the 16th International Conference on Computer Applications and Information Technology in the Maritime Industries . Volume 1, Hamburg.
Today, Big Data is getting popular in shipping where large amounts of information is collected to better understand and improve logistics, emissions, energy consumption and maintenance. In shipping, the Automatic Identification System (AIS) records millions of information of ships operations. However, to get the most of these big chunks of information specific technologies should be applied to process these data within an acceptable time. This paper presents a model to extract patterns from AIS records in the field of supply chain of offshore platforms. Here a solution using distributed processing framework based on Hadoop Hive queries (map/reduce) and Hadoop Distributed File Systems (HDFS) is developed. First, a short benchmark study is present to compare performance of Big Data technology in front of former technology. Second, results of the pattern extraction regarding navigational behaviour of Platform Supply Vessels are presented. Then, the new knowledge is introduce in a stochastic simulation to mimic the supply chain management of offshore platforms. The results shown that the proposed methodology is efficient to reproduce offshore logistic activities taking into account uncertainties related to operational matters, as well as weather uncertainties that affect the system. Moreover, big data technologies are greatly reducing time to extract pattern from considerable amount of data.
Marques, C. H.; Belchior, C. R. P.; Caprace, J.-D. J. E. M. (2017)
Proceeding of International Maritime Association of the Mediteranean (IMAM) , Lisbon, C.R.C. Press. Taylor & Francis Ltd.
Cepeda, M. A. F.; Pereira, N. N.; Kahn, S..; Caprace, J.-D. J. E. M. (2017)
Proceedings of the XXV Pan-American Conference of Naval Engineering, Maritime Transportation & Port Engineering, COPINAVAL 2017 , Ciudad de Panama, Panama. IPEN, Pan-American Institute of Naval Engineering (IPEN).
Maritime transport is responsible for about 2.5% of global greenhouse gas emis-sions, around 1000 million tons of CO2 annually. The situation of shipping emis-sions that strongly depends on future economic grows is aggravated by the fact that global Green House Gas (GHG) emission are predicted to increase between 50% and 250% by 2050. This increase is not compatible with the internationally agreed goal of keeping global temperature increase to below 2°C compared to preindustrial levels, which requires worldwide emissions to be at least halved from 1990 levels by 2050. Although, shipowners are facing barriers to imple-ment energy efficiency technologies to reduce CO2 mainly due to reliability, fi-nancial and economic constraints as well as complexity of change. Ships' energy consumption and CO2 emissions could be reduced by applying operational measures and implementing existing technologies. Further reductions could be achieved by implementing new innovative technologies. The aim of this study is to compare and review low carbon and advanced technologies that may help to reach the international GHG reduction goals. A comparison table describing the different technologies, the estimated capital cost, the technology readiness as well as the potential GHG reduction is drawn. The table also indicates if the technolo-gy is more adapted to new projects or refurbishment. The comparison may help the key players to select the most convenient technology for their new projects. It will also be helpful for conversion of existing vessels.
Fiasca, R. B. ; Assis, L. F. ; Pires Jr., F. (2017)
Proceeding of International Maritime Association of the Mediterranean Annual Conference . Volume 1, Lisboa. IMAM 2017 Annual Conference.
Simoes, R. U., Moita, J. V. M. O., Gormus, D., Caprace, J.-D. (2016)
Proceeding of the Rio Oil & Gas . IBP, IBP.
Considering that the price of crude oil is actually coming back to the lower levels existing before 2000’s, cost reductions is becoming a critical factor for offshore industry. Therefore, improving the offshore upstream supply chain efficiency is becoming a major challenge for the O&G companies. In this paper, we present a discrete-event simulation model that may evaluates alternative fleet size configurations taking into consideration uncertainty in weather conditions and unexpected delays. Innovation states in the use of automatic identification system (AIS) data as model input. A time depend historical database of 6 months for 90 platform supply vessels has been analyzed. Based on these data, a methodology has been developed to detect the most probable navigational behavior of the vessels (sailing, waiting at sea, loading/unloading at port, loading/unloading at platform, moored, etc.). Later, it is shown that straightforward statistical distributions can be used to characterize speed, loading and unloading times at port terminals, loading and unloading time at offshore platforms as well as mooring time. A discrete-event simulation (DES) model representing the Campos Brazilian basin that includes one port, 23 PSVs and 38 offshore production platforms has been used as a validation case. The preliminary results show a good accordance between the simulation outputs and real data. We suggest that this novel approach can be adopted as a tool to examine the efficiency of existing PSV fleets as well as to identify the effect of different operational and management strategies in offshore logistics activities such as adjusting the routes of vessels, deciding the fleet size, determining the composition of PSV fleets, optimizing the scheduling of platform clusters.
Muhabie, Y., Petcu, C., Rigo, P., Caprace, J.-D. (2016)
PIANC Yearbook 2015 . PIANC, PIANC.
The offshore wind energy development has shown a progress in the last ten years. Distance from the coast line and the depth of the water are getting increased from time to time. The transport and installation of offshore wind turbines is highly dependent on weather condition at sea. Any disturbance along the logistics chain could result in a signifi cant delay in the project completion. The purpose of this paper is to carry out a weather down time analysis for offshore wind turbine transport and installations considering the weather restriction criteria for each activities along the logistics chain. A Discrete Event Simulation (DES) model has been developed taking the vessel characteristics, distance matrix, installation methodology and sequence of activities into account. The results pointed out that the lifting operation causes higher down time over other activities and improving the lifting operations could result in a significant reduction in the overall project completion time. This paper also gives an insight how a simulation weather down time analysis could improve the decision support system in the offshore wind energy development industry at the planning phase.
Vieira, L. M., Ramos, R. F.; Assis, L. F.; Caprace, J.-D. , SOBENA (2016)
Congresso Nacional de Transporte Aquaviário, Construção Naval e Offshore . Volume 1. SOBENA, SOBENA.
In the context of shipbuilding, the block erection process is one of the most critical point of planning. It is known that the production cycle in the preassembly area determines the production capacity. Therefore, optimization of the shipbuilding activities is crucial to improve productivity and competi-tiveness. However, the tools commonly used in the design phase do not cover all stages of ship-building, allowing only an incomplete planning. Thus, the purpose of this work is to simulate the pre erection and erection processes of large ships to compare the effectiveness of different building strategies. In order to achieve this objective, a discrete-event simulation model have been developed which has the advantage to include all parameters of building processes providing results closer to reality. The analysis found that the production time using different sequences of building: ring, pyra-mid or layer can be significantly affected. The methodology provided is effective to identify the per-formance of different erection sequences. Therefore, this tool might be applied to identify the best assembly alternatives that improve shipyard productivity.
Moita, J. V. M. O., Baltazar, L. R. S., Molinas, E., Gallo, M. N., Vinzon, S. B., Caprace, J.-D. , PIANC (2016)
Proceeding of the Ninth International Conference On Coastal and Port Engineering in Developing Countries , Rio de Janeiro. PIANC-COPEDEC.
It has been shown how traffic simulations can be used to improve trade performance of approach channels and port logistic. Two specific situations merits to be highlighted. First, in some approach channels, fluvial currents combined with tidal currents may be too strong at certain stages of the tide to allow some ships to navigate safely. Second, depending on transit times and traffic, it may be possible to use tidal windows to bring in deeper drafts ships than would normally be acceptable. This implies that there will be access downtime for which the channel will not be available for such ships. Therefore, there is a need to include theses parameters into traffic simulation in order to improve the channel navigation safety as well as the port efficiency. In order to solve this problem, a discrete-event traffic simulation combined with a 2DH hydrodynamic model is proposed in this paper. A case study of the Amazon North Channel is studied because it is considered critical for navigation due to sandy banks migration, macro tides and limited depths (lower than 10 m). Both, astronomical tides and river flow are considered to assess the currents and under keel clearance. Therefore, together with ship speed and draft, the travelling and waiting times can be assessed. The results show the influences of ship draft and speed over water on tidal windows size for both upstream and downstream travels. Finally, this study suggests that the proposed model can improve the decision making regarding acceptable tidal windows. It will lead to a better safety and better efficiency of ports and channel operations.
Baltazar, L. R. S., Moita, J. V. M. O., Gallo, M. N., Vinzon, S. B., Caprace, J.-D. , SOBENA (2016)
Congresso Nacional de Transporte Aquaviário, Construção Naval e Offshore , Rio de Janeiro. SOBENA.
The North channel of the Amazon River is a dynamic coastal environments with a navigation chan-nel particularly sensible due to the limitation to the ships draft and the risk of running aground on sandbanks. The hydrodynamic of this area provides the deposition contributing to the for-mation/evolution of banks at the estuary mouth. The converging effect on the incident macro-tide induce an increase of its amplitude, with height above 3 m, beyond that, flood/ebb asymmetries and seasonally modulation are observed throughout the navigation channel. However, measure-ments of the levels take place in the coastal station in Ponta do Céu with a low predictability of levels over the 100 km of the approach channel. Thus, in order to contribute to the safety and effi-ciency of navigation, this work presents different improvements to forecast the water levels and navigable depths, through the operation of hydrodynamic modeling and discrete-event simulations of the traffic. With the simulation of water levels/currents results was possible to identify the tidal windows taking into account the tidal variations during differents spring tides scenarios and sea-sonality of the river. This research conclude that the inclusion of tidal windows in traffic simula-tions result positively in decision making for safer and efficient navigation in areas of macro tide.
Cepeda, M. A. F., Marujo, L. G., Assis, L. F., Caprace, J.-D. , SOBENA (2016)
Congresso Nacional de Transporte Aquaviário, Construção Naval e Offshore , Rio de Janeiro. SOBENA.
Currently, container ship operators have implemented in their fleets slow steaming strategies to raise the profit margins by reducing operational costs. However, some ship owners are not yet convinced of this practice because the navigation time is increasing that causes a reduction in the number of travels per year of the ship. The use of speed reduction by liner shipping has been widely discussed in the literature. Nevertheless, this effect has not been studied in bulk carriers be-cause they are navigating slower than container ships. This paper proposes a simulation model of a bulk carrier’s fleet composed of 13 ships from a unique ship-owner in three conditions: the actual condition of navigation, the slow steaming, and ultra-slow steaming. A discrete-event simulation model has been developed with a database of a bulk carrier fleet. The results obtained are the total fuel consumption, emissions, and cargo transported for one year. These values are show-ing that the fleet can be operated with higher efficiency when the slow steaming strategy is used. Indeed, the saving in fuel cost and emissions are balancing the reduction of the cargo transported per year.
Moita, J. V. M. O., Caprace, J.-D. , PIANC (2016)
Ninth International Conference On Coastal Engineering In Developing Countries , Rio de Janeiro. PIANC-COPEDEC.
Good planning and management of container terminal operations reduces waiting time of the vessels and lead to the improvement of the terminal productivity. Moreover, being faster in ports allows a ship to transit at slower speeds (slow steaming) and to save fuel as well as to reduce emissions. Important key factor to reduce unproductive times are the optimization of berth allocation, quay crane allocation as well as scheduling. However, it can only be done if a good understanding on how the resources are interacting and affecting the berthing time of ships is obtained. This paper investigates the effect of quay cranes assignments and scheduling on the container terminal productivity through stochastic simulations. A container vessel berthing simulation model is created based on the data warehouse of an actual container terminal. The uncertainties and unpredictable events related to operations are implemented using stochastic variables. Calibration of the simulation model is based on five operations of the same container carrier in the terminal. Following the setting of the stochastic parameters included in the model, the simulation is repeated until sufficiently large sets of iterations are available for statistical analysis. Results of the simulation of 9 scenarios considering various loading conditions and crane allocation are compared. Then, the dispersion of the net average berthing time and net cranes productivity are discussed and confronted to measured data. We advocate that simulation provide a good decision assistance tool to perform operational productivity studies for both ship owners (bay plan optimization) and container terminals (layout optimization). Therefore, some patterns and recommendations are formulated to help to improve the productivity in container terminals.
Monteiro, G. P.; Roppa, G. A.; Campos, C. C. L. F. E.; Selamoglu, A.; Assis, L. F., Caprace, J.-D. , SOBENA (2016)
Congresso Nacional de Transporte Aquaviário, Construção Naval e Offshore , Rio de Janeiro. SOBENA.
O ambiente atual da indústria naval vem exigindo cada vez mais sofisticação do planejamento estratégico com o objetivo de aumentar a competitividade. Dentro desse contexto, os estaleiros apresentam um enorme potencial de desenvolvimento. Para explorá-lo, destacam-se como ferra-mentas a otimização do aproveitamento de espaço e tempo dos processos referentes a seus pátios de aço. Esse artigo tem como objetivo o estudo da otimização do espaço e dos proces-sos utilizados nas operações do pátio de aço, ou seja, a análise de diferentes disposições do pátio, assim como de diferentes maneiras de movimentação das chapas. Foram analisados dife-rentes cenários do pátio de aço, através da utilização de ferramentas de simulação estocástica associadas à otimização computacional. Foi analisado como o sistema responde às variações da frequência de chegada das chapas de aço e da área de armazenamento, representado pelo núme-ro de pilhas de aço e sua capacidade. Os resultados obtidos comprovam que é possível, por meio do planejamento de logística, a redução significante dos tempos de operação e do trabalho em progresso (Working In Progress). O uso de técnicas de otimização auxiliadas por ferramentas de simulação apresenta-se como grande diferencial para o auxílio do planejamento estratégico garantindo uma maneira eficiente e de baixo risco de melhorar a produção na indústria de cons-trução naval.
Marques, C. H., Belchior, C. R. P., Caprace, J.-D. , FURG (2016)
Proceeding of the VII Seminar and Workshop in Ocean Engineering , Rio Grande. FURG.
Marine transport of natural gas, mostly in its liquid phase, is of growing importance in the global energy markets. The fleet of liquefied natural gas carriers is thereby increasing and being upgraded to enhance its performance. Since there is no well defined procedure about how to perform the selection of the propulsion system considering the peculiarities of this kind of vessel, this work intended to fill this gap. In other words, the present article aimed to propose an approach so that one could perform the optimised selection of liquefied natural gas carriers propulsion system mainly concerning financial aspects. Firstly, some fundamentals about liquefied natural gas and its transport were presented followed by reasons why the traditional steam turbine propulsion plant was abandoned and dual-fuel diesel engines have been applied instead. Then, a list of criteria was discussed and studies that inspired this work were summarised. A case study of a ship with cargo capacity of 174,000 m³ operating between Lake Charles and Tokyo Bay via Panama Canal has been selected. Owing to this route and environmental rules, the ship has to travel at three different levels of service speed unlike ordinary ones, which usually keep a steady speed throughout voyage. Maximising the net present value of the project is the objective function that is intended to be achieved by optimising eleven variables regarding synthesis, design and operation of the propulsion system. Finally, it is suggested that this work may assist marine engineers and shipowners to design and outline the operation of liquefied natural gas carriers.
Marques, C. H., Belchior, C. R. P., Caprace, J.-D. , SOBENA (2016)
Congresso Nacional de Transporte Aquaviário, Construção Naval e Offshore , Rio de Janeiro. SOBENA.
This study aimed to address the state-of-the-art of computer simulation models of marine diesel engines and the main computer applications. There are simple models based on transfer function or more complex models based on computational fluid dynamics. The models may be implemented through basic programming languages or dedicated packages of internal combustion engine simulation. Owing to the recent interest to reduce the gas emissions, dual-fuel engines are increasingly being used as primary propulsion in merchant ships. In this context, a simplified model of marine dual-fuel low-speed diesel engine has been developed. Through the normalisation of specific fuel consumption and exhaust gas data, clear trends approachable by polynomial curves or surfaces was revealed. Thus, by using the proposed model and knowing the characteristics of an engine at its nominal maximum continuous rating, it is possible to predict engine operation in any design point on the engine layout diagram, even at part load. The maximum deviations regarding the two simulated engines did not exceed -3.4%. In short, the developed model is a simple and effective tool for optimising the selection of dual-fuel low-speed diesel engines to be applied in ship propulsion systems.
Ronchini, P. M.; Assis, L. F. , SOBENA (2016)
Congresso Nacional de Transporte Aquaviário, Construção Naval e Offshore . SOBENA.
Uma questão fundamental na indústria de construção naval no Brasi é o chamado risco estaleiro, que está associado a um histórico de mau desempenho na execução de projetos no que se refere ao cumprimento de prazos e orçamentos. Assim, o controle do progresso físico e financeiro dos empreendimentos é uma medida de fundamental importância para manter o risco em níveis aceitáveis. No Brasil, praticamente todos os projetos de construção naval contaram com o financiamento do Fundo de Marinha Mercante, que, durante muito tempo, não possuia um sistema mínimo de acompanhamento. Exigia apenas um orçamento padrão conhecido como a Ordem de Serviço no 5 (OS-5). Todavia, mais recentemente, passou-se a se exigir que os projetos financiados pelo FMM apresentem uma Estrutura Analítica de Projeto (EAP) e Quadro de Usos e Fontes (QUF). O presente trabalho comparou o sistema de acompanhamento da construção de um rebocador portuário seguindo os padrões atualmente adotados pelo Fundo da Marinha Mercante com o acompanhamento realizado utilizando-se dois sistemas computacionais, o Primavera® e o Synchro®, que utilizam o método Earned Value Management para verificar o avanço da obra. O segundo programa citado ainda possibilita a visualização 4D do andamento da construção.
de Araujo, A. O., Rezende Filho, M.; Pires Junior, F. C. M. (2016)
Proceeding of 26th International Congress on Waterborne Transportation, Shipbuilding and Offshore Constructions, SOBENA 2016 . Volume 1, SOBENA.
O Fundo da Marinha Mercante – FMM é a principal fonte de financiamento para as indústrias de construção naval e transporte aquaviário no Brasil. Para todos os projetos financiados, os estaleiros são obrigados a apresentar um orçamento detalhado de custos de produção. O Conselho Diretor do FMM e os agentes financeiros, que são bancos públicos federais, devem avaliar esses orçamentos para evitar sobrefinanciamento e excesso de ineficiência produtiva. Este artigo apresenta as principais características de um sistema computacional orientado para a gestão de uma base de dados de custos de produção e para suporte a análise de orçamentos.
Rodrigues, N. C. C. ; Simoes, R. U. ; Pinto, L. A. V. ; Assis, L. F. ; Caprace, J.-D. J. E. M. , Bertram, V. (2016)
Proceeding of 16th International Conference on Computer Applications and Information Technology in the Maritime Industries . Volume 1, Cardiff.
Muhabie, Y. T.; Patcu, C.;Rigo, P.;; Caprace, J.-D. J. E. M. (2016)
Annual General Assembly of the World Association for Waterborne Transport Infrastructure (PIANC) .
The offshore wind energy development has shown a progress in the last ten years. Distance from the coast line and the depth of the water are getting increased from time to time. The transport and installation of offshore wind turbines is highly dependent on weather condition at sea. Any disturbance along the logistics chain could result in a signifi cant delay in the project completion. The purpose of this paper is to carry out a weather down time analysis for offshore wind turbine transport and installations considering the weather restriction criteria for each activities along the logistics chain. A Discrete Event Simulation (DES) model has been developed taking the vessel characteristics, distance matrix, installation methodology and sequence of activities into account. The results pointed out that the lifting operation causes higher down time over other activities and improving the lifting operations could result in a signifi cant reduction in the overall project completion time. This paper also gives an insight how a simulation weather down time analysis could improve the decision support system in the offshore wind energy development industry at the planning phase.
de Araujo, A. O., Rezende Filho, M.; Pires Junior, F. C. M. (2016)
Proceeding of International Conference on Naval Architecture and Ocean Engineering, NAOE2016 . Volume 1, Saint-Petersburg, Russia.
The Merchant Marine Fund – FMM is the main source of financing for the shipbuilding and shipping industries in Brazil. Since the interest rates are subsidized, the shipyards are required to present a detailed ship construction budget. The FMM Agency and the commissioned governmental banks in charge of the loans management are supposed to assess these budgets to prevent overpricing and production inefficiencies. This paper presents the main features of a Decision Support System oriented to management of a production cost database and to modelling and running the relevant statistical analysis.
Schachter, R. D. (2016)
Proceeding of 26th International Congress on Waterborne Transportation, Shipbuilding and Offshore Constructions, SOBENA 2016 , Rio de Janeiro. SOBENA, SOBENA.
Este trabalho apresenta o desenvolvimento um software a ser integrado a um sistema computacional, que também funciona autonomamente, para determinar o Equilíbrio Dinâmico e Resistência ao Avanço de lanchas planadoras com métodos analítico-empíricos (Savitsky e Virtual Prismatic Hulls) e de cascos de deslocamento convencional e de alta velocidade com método estatístico (Holtrop). É parte de um módulo que, além do equilíbrio dinâmico dos cascos mencionados, fará o equilíbrio dinâmico das demais embarcações de alto desempenho baseadas em sustentação hidrodinâmica, aerodinâmica e aerostática, integrando diversas rotinas já programadas. O módulo integrará um Sistema Computacional em fase final de desenvolvimento, o Solution Focused Design System (SFDS), permitindo testar configurações e desenvolver projetos de embarcações. Esta parte do módulo de Equilíbrio Dinâmico é um desenvolvimento inédito, por tratar da sustentação dinâmica, buscar o ponto de equilíbrio (centro de pressão, com o peso e CG) e depois determinar o arraste ou apenas calculando a resistência, dependendo da concepção. É feito para diversas velocidades (com gráficos), além de abordar cálculos de estabilidade dinâmica longitudinal (porpoising). O software e sua interface foram desenvolvidos com uma ergonomia de menus, resultados numéricos, diversos gráficos de todos os parâmetros calculados, animação da variação do trim com a velocidade, avisos de inconsistência de parâmetros, que permite avaliar alternativas de projeto, agilizar os cálculos e provê a versatilidade de passar de um método a outro, importando dados, permitindo o input (em qualquer ordem ou unidade) dos dados de entrada, faixas desejadas e propriedades (há defaults) em dois sistemas de unidades, convertendo-os e apresentando ambos, assim como os dados de entrada e de saída, organizados em colunas lado a lado. Os resultados podem ser exportados para planilhas Excel, além das telas poderem ser impressas. Um exemplo da aplicação é apresentado.
Schachter, R. D.; Monteiro, F. V. (2016)
Proceeding of 26th International Congress on Waterborne Transportation, Shipbuilding and Offshore Constructions, SOBENA 2016 , Rio de Janeiro. SOBENA, SOBENA.
Um dos fatores essenciais para o sucesso de um projeto de uma embarcação é a compatibilidade entre os softwares utilizados. Atualmente, o mercado possui alguns softwares na área de projeto na-val que procuram integrar cada vez mais todas as fases de projeto no mesmo sistema e dentre esses encontram-se os produtos comerciais NAPA e o Maxsurf. Esse trabalho tem como intuito realizar uma análise comparativa do funcionamento dos softwares comerciais NAPA e Maxsurf. Para isso, foi desenvolvido o projeto da embarcação Fast Supply Vessel (FSV), em paralelo, no NAPA e no Maxsurf, sendo anotadas todas as diferenças percebidas, como a facilidade de utilização, qualidade da interface, tempo necessário para definir os dados de entrada, tempo de processamento das análises, integração do programa, clareza dos dados de saídas. A estruturação e a sequência de utilização em cada Sistema foram analisadas, mostradas e comparadas. O processo de projeto aplicado utilizou uma metodologia comum aos dois, desenvolvida para o proje-to e envolveu fatores como a definição da Forma (de deslocamento de alta velocidade), Hidrostáticas, Cruzadas, Resistência, Propulsão (supercavitante), Borda Livre, Arqueação, Estrutura, Compartimen-tação, Arranjo Geral, Peso Leve, Condições de Carregamento, Equilíbrio, Estabilidade Intacta e Ava-riada (probabilística), Seakeeping, etc. A cada fator executado, comparações são feitas, resumidas e analisadas no final do trabalho. A embarcação FSV em estudo transporta 50 Passageiros, 315 t de Óleo e Água e 250 t de Carga e opera a 22 nós.
Cepeda, M. A., Caprace, J.-D. (2015)
Proceeding of the Offshore Technology Conference . Volume 1. Offshore Technology Conference.
This paper describes the use of navigation data to generate a model in order to answer to the following questions. What is the ship with less efficiency in my fleet? What is the best strategy to improve the overall efficiency of my fleet? What is the ship that I should sell in priority? What is the influence of this maintenance policy on the performance of my fleet? The application case of this paper is based on one fleet of 13 ships containing 223 trips that gather approximately 6844 traveling days. The developed mathematical model is using Key Performance Indicators (KPIs) based on Fuel consumption performance, Aging, Work performance, Sea condition, Steaming Time, Emissions, and Port Logistic. Afterwards a Data Envelopment Analysis (DEA) model is discussed. Both laden and ballast conditions are considered. Afterwards, a Multi Criterion Decision Analysis (MCDA) is proposed in order to assist the ship-owner in the improvement of the performance of their fleet. A methodology to compare the efficiency of various ships in a fleet has been introduced in this paper and it provides a way to compare similar or different ship types and sizes during their operation. This study offers a method to exclude the engineer subjectivity by assessing the ship efficiency from different aspects using Data Envelopment Analysis. The results suggest that this new methodology can efficiently provide a multi-criteria decision framework to improve maintenance and fleet management strategies. The outcomes show a performance classification of the ships inside a fleet in a way that best and worst ships are identified at any moment. These findings provide a new way to address efficiency and performance in ship fleet management. Developed methodology allows to minimize operational resources hence reduce costs.
Suzen, R. O., Moita, J., CAPRACE, J.-D. (2015)
14th International Conference on Computer Applications and Information Technology in the Maritime Industries . Volume 1, Ulrichshusen, Germany, Technische Universität Hamburg-Harburg.
This paper proposes a productivity analysis of a new bay plan design which intends to be faster during loading and unloading at container terminals. The operational efficiency of a container terminal is investigated for various conditions and its effect on berthing time is reviewed. A fully parametrical Discrete Event Simulation (DES) model is created and calibrated based on a 7 months’ statistical data set of a real container terminal. The uncertainties are implemented using semi-random numbers. Finally, the results concerning efficiency of a new bay plan were obtained, where high/low tide, higher/lower crane speeds and multiple crane usage conditions are considered.
Cepeda, M., Caprace, J.-D. (2015)
Proceeding of the 5th World Maritime Technology Conference 2015 , Providence, Rhode Island, USA. WMTC.
The world merchant fleet has increased in the last decade producing an increase of fuel consumption and greenhouse gas emissions (GHGs). Thus, the concerns of ship-owners to implement alternatives to improve the fleet efficiency are growing. However, shipowners are facing barriers to implement energy efficiency technologies mainly due to reliability, financial and economic constraints as well as complexity of change. Actually several shipowners are using onboard data measurements systems that collect navigation and propulsion information of their ships. Therefore, after being sent via satellite and stored in data warehouse, these data are being made available to assess the performance of their fleets. This paper describes the use of these data to generate models in order to answer to the following questions: What is the ship with least efficiency in my fleet? What is the best strategy to improve the overall efficiency of my fleet? What is the ship that I should sell in priority? What is the influence of this maintenance policy on the performance of my fleet? The application case of this paper is based on one fleet of 13 ships containing 223 trips that gather approximately 6,844 traveling days. After the definition of the key performance indicators (KPIs), a data envelopment analysis (DEA) models is discussed. Then, a multicriterion decision analysis (MCDA) model is compared to the DEA outputs. The results suggest that this new methodology can efficiently provide a multicriteria decision framework to shipowners avoiding engineers’ subjectivity. These findings offer a new way to address efficiency and performance in ship management.
Muhabie, Y., Caprace, J.-D., Petcu, C., Rigo, P. (2015)
Proceeding of the 5th World Maritime Technology Conference 2015 , Providence, Rhode Island, USA. WMTC.
The offshore wind energy development is highly affected by the condition of the weather at sea. Hence, it demands a well-organized planning of the overall process starting from the producers’ sites until the offshore site where the turbines will finally be installed. The planning phase can be supported with the help of Discrete Event Simulation (DES) where weather restrictions, distance matrix, vessel characteristics and assembly scenarios are taken into account. The purpose of this paper is to simulate the overall transport, assembly and installation of the wind turbine components at sea. The analysis is carried out through DES considering both the real historical weather data (wind speed and wave height) and probabilistic approach. Results of the study, applied to the real Offshore Wind Farm (OWF) configuration, are showing a good agreement between the two proposed models. The results point out that the probabilistic approach is highly affected by the semi-random numbers used to model the stochastic behavior of the input variable so that several iterations (200 to 400) are required to reach the convergence of the simulation outputs. We suggest that seasonality of the outputs of both models are preserved, i.e. the variation of the results depending on the variation of the weather along the year. These findings provide a new framework to address risks and uncertainties in OWF installations.
Cepeda, M., Silva, R., Caprace, J.-D. (2015)
Proceeding of the XXIV Pan-American Conference of Naval Engineering, Maritime Transportation & Port Engineering, COPINAVAL 2015 , Montevideo, Uruguai. IPEN, Pan-American Institute of Naval Engineering (IPEN).
Nowadays, the oil offshore industry is making every effort to improve the logistic in oil production. Supply of offshore platforms require a high level of service using minimal logistic resources. Weather conditions and vessel off-hire are the main variables that induces delays in operations planning. These delays postpone or disturb the oil production in offshore platforms and FPSOs. Actual cargo logistic maritime fulfillment indicator shows that there is a huge potential for improvement. The objective of this paper is to forecast the delays that are occurring during the delivery of the supplies for offshore platforms operating in Brazil. In order to achieve this goal, a database of 2 851 offshore supply vessels travels have been processed with several data mining tools such as apriori, decision tree and multi-layer perceptron. The type of cargo (dry bulk, liquid bulk or container), the cargo priority, and type of operation (load, backload or transshipment) are some of the input parameters of the models developed in this study. The findings provide a new way to address efficiency and performance supply logistics of offshore platforms even if some future model improvements are required. Knowing in advance were the delays are more susceptible to occurs in the supply chain allows the planners to anticipate their strategies and delivery routes.
Cepeda, M., Caprace, J.-D. (2015)
Proceeding of the XXIX Congresso de Pesquisa e Ensino em Transportes , Ouro Preto, Brazil. ANPET, ANPET.
Operators of container ships have recently implemented slow steaming strategies to reduce the emissions and raise the profit margins by reducing operational costs. However, some ship owners are not yet convinced of this practice because the navigation time is increasing. Liner shipping enterprises use slow steaming in their fleets, but this effect has not been studied in bulk carriers because they are navigating slower than container ships. This paper proposes a simulation model of a bulk carriers fleet in three conditions: the actual condition of navigation, the slow steaming and ultra-slow steaming. We developed a Discrete Event Simulation model with a real database of a bulk carrier fleet. The results obtained are the total fuel consumption and the cargo transported for one year. These values are showing the saving in fuel cost, reflecting the reduction of operational costs.
Caprace, J.-D.; Constantinescu, A.; Chirica, I., Rigo, P. (2014)
Proceeding of the 25 Congresso Nacional de Transporte Aquaviário, Construção Naval e Offshore (SOBENA) .
This paper introduces a complexity metric for ships and offshore structures. The goal is to provide the designers and managers with such information throughout the design process so that an efficient design is obtained at the first design run. Real-time assessment of complexity and quality measurements is rather imperative to ensure efficient and effective optimality search, and to allow real-time adjustment of requirements during the design. Application on a Handling Tug Supply boat (AHTS) show that the new method is effective in giving a complementary aid to decision process for ship designers.
Petroianu, L. P. G.; Pires Júnior, F. C. M.; Assis, L. F. (2014)
Proceeding of 25th International Congress on Waterborne Transportation, Shipbuilding and Offshore Constructions, SOBENA 2014 . Volume 1. SOBENA, SOBENA.
O presente artigo discute como o Lean Manufacturing pode auxiliar no processo de melhoria e reestruturação da indústria de construção naval brasileira que atualmente se mostra com grande demanda, mas baixa capacidade de atendê-la e fraca competitividade. O principal objetivo do Lean é o aumento de produtividade e redução de custos através da eliminação de operações desnecessárias, consideradas como desperdícios. O conceito já é utilizado em diferentes segmentos industriais e, apesar de ter sido desenvolvido para processos de produção seriada, com algumas adaptações, também tem se mostrado eficiente para outros tipos de indústria, como as orientadas ao objeto, por exemplo, aeronáutica e naval. O artigo analisa os benefícios que o Lean Manufacturing pode trazer para a melhoria de um processo de construção naval e como pode ser implementado, focando em um estudo de caso de uma linha de construção de blocos planos de um estaleiro de médio porte no Rio de Janeiro. O trabalho apresenta uma metodologia que pode ser empregada em processos simples ou agregados no ambiente da construção naval brasileira, para incorporar os paradigmas da filosofia Lean.
Pires Junior, F. C. M., de Araujo, A. O. (2014)
Proceeding of 25th International Congress on Waterborne Transportation, Shipbuilding and Offshore Constructions, SOBENA 2014 . Volume 1, Rio de Janeiro, SOBENA.
O trabalho apresenta um modelo de análise de opções reais para apoio a decisão de investimento em navios petroleiros. O modelo considera a flexibilidade gerencial para abandono e interrupção do projeto, ou seja, venda do navio e lay-up, durante a vida útil do projeto. A análise é baseada na simulação de Monte Carlo do fluxo de caixa do projeto, considerando o afretamento time-charter em contratos anuais. O modelo considera que a cada ano o investidor decide a continuação, interrupção ou abandono do projeto. Os projetos interrompidos são analisados para continuação em lay-up, retorno a operação ou venda do navio. O critério de decisão é o do Equivalente Certo positivo, descontado o fluxo futuro à taxa de desconto livre de risco. Para o cálculo do Equivalente Certo é considerada a função utilidade exponencial, que tem como parâmetro o coeficiente de aversão a risco do investidor. Os resultados são parametrizados em relação ao coeficiente de aversão a risco, cujo efeito no valor de opção e, consequentemente, na decisão de investimento é analisado.
Pires Jr., F. C. M.; Uchoa Neto, A. G. (2014)
Proceeding of 25th International Congress on Waterborne Transportation, Shipbuilding and Offshore Constructions, SOBENA 2014 . Volume 1. SOBENA, SOBENA.
Na prática mundial dos transportes marítimos, o atendimento de navios em terminais graneleiros obedece à ordem de chegada (first-in-first-out), e o tempo de estadia (lay-time) é calculado a partir do aviso de chegada do navio (NOR – notice of readiness). Com o objetivo de promover a redução, simultaneamente, do custo de combustível e do impacto ambiental dos navios, bem como do congestionamento nos portos, têm sido propostos sistemas de chegada virtual. O presente trabalho apresenta uma análise do impacto potencial do sistema de chegada virtual, com controle de velocidade de navios, para um terminal típico de minério de ferro. O modelo analisado baseia-se na estimativa do tempo de chegada do navio, navegando na velocidade de serviço, a partir da entrada em uma região de controle definida por uma circunferência centrada no porto de destino. A partir da estimativa do tempo de chegada, o navio é colocado na fila de atendimento, e a velocidade pode ser otimizada, minimizando o consumo de combustível, e atendendo, para cada navio, as restrições de velocidade máxima igual à velocidade de serviço, e velocidade mínima para operação segura. Para estimativa dos impactos, foi empregado um modelo de simulação para o caso de um terminal típico de exportação minério de ferro, com movimentação de carga própria, berço único e apenas um tipo de minério. A frota é composta de navios capesize. A análise inclui os custos de combustível, emissão de poluentes e formação de filas. São considerados os efeitos combinados de variações de distâncias de controle e de níveis de incerteza na operação do porto. Os resultados indicam que, superadas as dificuldades relativas aos atuais padrões de contratação de navios e de operação de terminais, a adoção de chegada virtual tem significativo potencial de impacto econômico e ambiental.
Czarneski, F. R. ;Pires Jr., F. C. M.; Botelho, S.S.C. ; Duarte Filho, N. ; Abdallah, P. R. (2014)
Proceeding of 25th International Congress on Waterborne Transportation, Shipbuilding and Offshore Constructions, SOBENA 2014 . Volume 1, Rio de Janeiro. SOBENA, SOBENA.
Pires Jr., F. C. M.; Monteiro, d. S. E. F. (2014)
Proceeding of 25th International Congress on Waterborne Transportation, Shipbuilding and Offshore Constructions, SOBENA 2014 . Volume 1. SOBENA, SOBENA.
O trabalho apresenta uma análise da aplicabilidade do Mecanismo de Desenvolvimento Limpo (MDL), criado pela Conferência das Partes da Convenção Quadro das Nações Unidas sobre Mudanças do Clima (CQNUMC) como uma forma de ajudar os países a cumprirem as metas do Protocolo de Quioto, no processo de redução de emissões dos gases de efeito estufa. O MDL tem sido empregado, internacionalmente, em vários segmentos da economia. Entretanto, observa-se uma significativa concentração em projetos em apenas alguns setores, sendo o setor de transportes pouco utilizado em projetos de MDL. Em particular no Brasil, existem poucos projetos de transporte, sendo apenas um relacionado com o modal marítimo, e nenhum com a navegação interior. Para analisar o potencial de aplicação nos transportes fluviais no Brasil, o trabalho concentra-se em um estudo de caso, para um tráfego representativo do segmento mais importante do setor no Brasil. Foi considerado o caso de um projeto de implantação de uma hidrovia no Rio Teles Pires - Tapajós, para escoamento de soja do centro-oeste, para exportação. O modelo considera o transporte até o porto de embarque por rodovia, e o transporte hidroviário entre Sinop - MT e o porto de Santarém - PA, para exportação e compara com as rotas já existentes. O estudo pretende mostrar que a construção da hidrovia Teles Pires - Tapajós atende aos critérios básicos de um projeto de MDL.
Czarneski, F. R. ;Pires Jr., F. C. M.; Botelho, S.S.C. ; Duarte Filho, N. ; Abdallah, P. R. (2014)
Proceeding of XXI Simpósio de Engenharia de Produção , AURU, SIMPEP.
Schachter, R. D.; Silva, M. S. (2014)
Proceeding of 25th International Congress on Waterborne Transportation, Shipbuilding and Offshore Constructions, SOBENA 2014 , Rio de Janeiro. SOBENA, SOBENA.
Este trabalho apresenta o desenvolvimento um software integrado a um sistema computacional existente para fazer os cálculos necessários do projeto estrutural aplicando as regras para High Speed Craft da Sociedade Classificadora ABS para embarcações monocasco construídas em aço ou alumínio. Este programa de computador é a evolução de um anterior, que aplica as regras do ABS para embarcações em aço de comprimento igual ou menor que 90 metros, e as incorpora, aperfeiçoando sua interface, ergonomia de telas, menus, imagens e procedimentos. A intenção deste desenvolvimento, foi de agilizar o processo de cálculo estrutural no projeto preliminar, sem perda de precisão: o programa importa as linhas da forma do casco definida no sistema, o usuário prescreve o cavernamento e o espaçamento entre longarinas (há sugestão), escolhe a regra e o material e pede para calcular as regras. O programa calcula todas as regras, apresenta todos os elementos e suas espessuras, calculadas e adotadas por tabela comercial (aço ou alumínio), determina e dimensiona todas as cavernas (por interpolações cúbicas da forma), que o usuário pode editar (excluir, acrescentar). O programa provê visualização de cada caverna, com todos os elementos estruturais selecionados, com dimensões e espessuras calculadas, modificáveis pelo usuário, como, sicordas, escoas, reforços secundários longitudinais, fundo-duplo, conveses, anteparas longitudinais e transversais, hastilhas, cavernas, longarinas, etc., gerando planos nas três vistas principais. Este processo é feito de um menu dos elementos, selecionáveis em qualquer ordem e que podem ser alterados interativamente, com avaliações parciais. O programa calcula, a cada momento, o Peso de Aço e Centro de Gravidade (com listagem de todos os elementos selecionados, com espessuras reais) da embarcação e sua Resistência Estrutural, calculando o Módulo de Seção e Momento de Inércia, comparando-os com os valores mínimos de regra e analisa, a cada tentativa, se a embarcação será ou não resistente longitudinalmente. Um exemplo de aplicação é apresentado.
Schachter, R. D.; Melo, V. V (2014)
Proceeding of 25th International Congress on Waterborne Transportation, Shipbuilding and Offshore Constructions, SOBENA 2014 , Rio de Janeiro. SOBENA, SOBENA.
O presente artigo analisa tecnicamente uma alternativa inovadora de embarcação para apoio a exploração de petróleo e gás na região da Bacia de Santos, através da apresentação do projeto conceitual de um navio de dimensões reduzidas para evitar congestionamento de linhas, com cerca de 30 metros de comprimento, do tipo SWATH (Small Waterplane Area Twin Hull), para suporte a inspeção e manutenção de estruturas e equipamentos submersos através do mergulho raso, mergulho saturado e operação de ROVs (Remotely Operated Vehicles). As vantagens e desvantagens inerentes a este tipo peculiar de multicasco são julgadas através dos dados recorrentes de cada etapa do projeto conceitual de um navio RSV (ROV Support Vessel) com velocidade de 16 nós, onde o objetivo é demonstrar que a embarcação específica com essas características, onde se destacam uma maior estabilidade transversal e um melhor comportamento em ondas, seja atraente e viável para operação na região de Bacia de Santos, provando sua eficácia em relação a monocascos e catamarans, comumente utilizados para esta finalidade. A forma do casco foi otimizada utilizando-se o método de Michell, incluindo diferentes alternativas de forma e estudando a influência da distância entre cascos. Os sistemas propulsivo e de posicionamento dinâmico foram selecionados. Sua estrutura foi dimensionada em alumínio (ABS – High Speed Craft), além de projetados seu arranjo geral e calculados o peso leve e a estabilidade.
Schachter, R. D.;Souza, L. A.; Fanchini, R. T.; Melo, V. V. (2014)
Proceeding of 25th International Congress on Waterborne Transportation, Shipbuilding and Offshore Constructions, SOBENA 2014 . SOBENA, SOBENA.
O presente artigo analisa tecnicamente uma alternativa inovadora de embarcação para apoio a exploração de petróleo e gás na região da Bacia de Santos, através da apresentação do projeto conceitual de um navio de dimensões reduzidas para evitar congestionamento de linhas, com cerca de 30 metros de comprimento, do tipo SWATH (Small Waterplane Area Twin Hull), para suporte a inspeção e manutenção de estruturas e equipamentos submersos através do mergulho raso, mergulho saturado e operação de ROVs (Remotely Operated Vehicles). As vantagens e desvantagens inerentes a este tipo peculiar de multicasco são julgadas através dos dados recorrentes de cada etapa do projeto conceitual de um navio RSV (ROV Support Vessel) com velocidade de 16 nós, onde o objetivo é demonstrar que a embarcação específica com essas características, onde se destacam uma maior estabilidade transversal e um melhor comportamento em ondas, seja atraente e viável para operação na região de Bacia de Santos, provando sua eficácia em relação a monocascos e catamarans, comumente utilizados para esta finalidade. A forma do casco foi otimizada utilizando-se o método de Michell, incluindo diferentes alternativas de forma e estudando a influência da distância entre cascos. Os sistemas propulsivo e de posicionamento dinâmico foram selecionados. Sua estrutura foi dimensionada em alumínio (ABS – High Speed Craft), além de projetados seu arranjo geral e calculados o peso leve e a estabilidade.
Tokola, H.; Niemi, E.; Assis, L.F. (2013)
Proceeding of the International Conference on Computer Applications in Shipbuilding (ICCAS) , Busan, South Korea.
In shipbuilding, blocks are erected to the hull and welded together to form the ship. Welding of blocks after erection involves lots of variation, especially when compared to the production of the blocks, which can be done in a factory environment. Therefore, it is worthwhile to make an erection sequence that optimizes the welding. This paper introduces an optimization model to sequence the erection so that as much welding as possible occurs as early as possible. The model is used to optimize the erection sequence of a Suezmax tanker ship by solving the optimization model using a local search heuristic. Optimized sequence is compared to the sequences got from aft-to-fore, bottom-up and pyramid erection strategies and, further, simulation is used to study how much benefit can be obtained by the optimized sequencing in different capacity conditions.
Pires Jr., F.; Rezende Filho, M. (2013)
Proceeding of 16th International Conference on Computer Applications in Shipbuilding (ICCAS) , Busan. Royal Institution of Naval Architects.
The paper presents the main features of a computer system for support the analysis of investment in ships, based on Real Options Analysis – ROA and Monte Carlo simulation. ROA has been increasingly adopted for large projects, subject to high degree of uncertainty and presenting significant managerial flexibility. Despite of the recognized applicability in shipping, ROA is not normally applied, mainly because of the technical and operational complexity. The system aims at overcoming these problems, and was designed to make feasible ROA application by non-specialists. The proposed ROA methodology for shipbuilding projects may incorporate options of abandon, defer or lay-up. The models for stochastic series of time-charter rates and ship prices, necessary for ROA, may be automatically or interactively selected. The system also allows the interactive definition of the cash flow structure, including the managerial options to be considered. The architecture of the computer system and the user interface are discussed.
Pires Jr., F.; Azevedo, I. R. ;Assis, L. F. ; ; Vieira, C. L. B. (2013)
Proceeding of 15th International Congress of the International Maritime Association of the Mediterranean, IMAM 2013 , A Coruña, Spain. IMAM, IMAM.
Ferreira, R. A. O.; Pires Jr., F.; Assis, L. F. (2013)
Proceeding of XXIII Pan-American Conference of Naval Engineering, Maritime Transportation & Port Engineering, COPINAVAL 2013 , Isla de Margartita, Venezuela. IPEN, IPEN.
Assis, L.F., Pires, F. C. M., Trevisani, C., Freire. R. M., Baptista, M., Portugal, B. (2012)
Proceeding of the 24 Congresso Nacional de Transporte Aquaviário, Construção Naval e Offshore (SOBENA) . SOBENA, SOBENA.
Os processos de montagem, pré-edificação e edificação de blocos podem ser considerados críticos para grande parte dos estaleiros de construção naval. Essas fases construtivas apresentam alta complexidade de programação, principalmente no caso de construção simultânea de navios com grande número de blocos de portes e conteúdos de trabalho diferentes. Além das restrições técnicas, que exigem que determinadas seqüências de atividades sejam respeitadas, o compartilhamento de recursos de movimentação é outro desafio para a gestão de processos. O presente trabalho apresenta um modelo de simulação de eventos discretos para facilitar a análise dos principais processos que ocorrem durante a construção simultânea de navios. O modelo desenvolvido proporciona ferramenta genérica de estudo do comportamento de sistemas, sendo possível adequá-lo a diferentes tipos de estaleiros, ou navios, bastando apenas alterar a base de dados acessados. O estudo pretende mostrar o potencial da técnica no suporte à tomada de decisões estratégicas, e no controle do desempenho de sistemas produtivos.
Pires Jr., F.; Souza, F. C. (2012)
Proceeding of 2012 International Research Conference on Short Sea Shipping, SSS2012 . Volume 1, Lisbon, Portugal .
F.C.M. Pires Jr. ; L.F. Assis ; M. Rezende e C.L.B. Vieira ; N. Duarte Filho ; S.S.C. Botelho (2012)
Proceeding of 2012 International Conference on Offshore and Marine Technology: Science and Innovation . Volume 1, Rio Grande, IEEE.
Após um longo período de crise, a indústria naval brasileira está passando por um novo processo de expansão. Entretanto, alguns dos problemas críticos que ainda persistem podem vir a impor barreiras à consolidação do setor. O risco do estaleiro apresenta-se como um dos principais problemas da indústria. O controle do progresso físico e financeiro dos empreendimentos é uma medida de fundamental importância para manter o risco em níveis aceitáveis. O presente trabalho apresenta as principais características de um sistema computacional desenvolvido para prover um controle abrangente do processo de construção e uma avaliação contínua de riscos.
Pires Jr., F.C.; Barauna Vieira, C.; Assis, L. F.; Queiroz, J.V. (2012)
Proceeding of nternational Conference on Value Chain Sustainability, ICOVACS 2012 . Volume 1, Izmir, Turkey. Izmir University of Economics, Izmir University of Economics Publications.
The shipbuilding sector is the main element of the shipping industry supply chain. As the shipbuilding itself is a very unstable and volatile industry, it becomes a critical source of risk for shipping investors. The problem is particularly critical in developing countries. The Brazilian maritime industry is experiencing a very rapid expansion process. A number of greenfield shipyards projects are under development as well as the modernization and expansion of existing shipyard facilities. The general economic growth has provoked the increasing of coastal shipping activities and consequently an increasing demand for domestic ship construction as the cabotage trades are reserved to national flagged ships. However, the poor performance records and the lack of continuity of shipyard operations are obstacles for shipowners to order newbuildings. The development of shipbuilding risk evaluation tools will be a significant contribution to the maritime industry recovery in Brazil. This paper presents a multicriteria approach to establish a risk rating for Brazilian shipyards. The methodology is then applied to the analysis of a set of typical shipbuilding companies. The shipyard risk rating is based on accounting and financial indicators , operational performance and technical and managerial capabilities and is useful to financers, insurers and other stakeholders, besides the shipowner , in the decision making process.
Queiroz, J. V. d.; Pires Jr., F. C. M. (2012)
Proceeding of 24th International Congress on Waterborne Transportation, Shipbuilding and Offshore Constructions, SOBENA 2012 . Volume 1, Rio de Janeiro. SOBENA, SOBENA.
A indústria de construção naval no Brasil passou por um período de profunda crise nos anos 80 e 90, mas vive agora uma fase de expansão decorrente principalmente da forte demanda do setor de exploração e produção de petróleo offshore. Nesta fase de recuperação, os riscos ainda são altos e isso gera um ambiente de incerteza, que representa um obstáculo para a contratação de novas construções por armadores privados. Com isso, o desenvolvimento do setor no país fica prejudicado. Neste contexto, o presente trabalho apresenta uma análise comparativa de riscos da construção naval no Brasil, sob o ponto de vista de armadores ou instituições financeiras. É apresentado o desenvolvimento de uma metodologia para o tratamento do risco-estaleiro. São feitas duas abordagens: na primeira, são tratados os principais riscos no setor naval no Brasil, sob ponto de vista do armador, para a execução de um projeto. Na segunda, são tratados os principais riscos a serem considerados na elaboração de um rating do risco-estaleiro, observando o estaleiro como empresa. A metodologia proposta é baseada em uma estrutura analítica onde os riscos são apresentados de forma hierárquica. Para ilustrar a aplicabilidade do modelo foram idealizados estaleiros representativos do setor no Brasil.
Weiss, J. M. G.; Schachter, R.; Pires Jr., F.; Morishita, H. M.; Mendes, A. B.; Tancredi, T. P.; ;Viterbo, J. C. (2012)
Proceeding of 24th International Congress on Waterborne Transportation, Shipbuilding and Offshore Constructions, SOBENA 2012 . SOBENA, SOBENA.
O artigo apresenta resultados parciais do projeto conceitual de uma embarcação de apoio marítimo destinada a atender aos requisitos operacionais da região de petróleo e gás localizada na Bacia de Santos. Esta região, distante cerca de 300 quilômetros de costa, se caracteriza prela prevalência de condições ambientais mais adversas e/ou bastante distintas daquelas encontradas em outras localidades do mundo. Para enfrentar as grandes distâncias envolvidas, bem como as condições ambientais mais severas, uma nova geração de embarcações de apoio está sendo envolvida. Na fase de projeto do casco foram estudadas duas vertentes de projeto: (1) variações sistemáticas das formas de popa, dos tipos de proa e do centro de carena, visando minimizar a resistência ao avanço e os movimentos em ondas (seakeeping) e (2) definição por otimização paramétrica em função das funcionalidades exigidas para a embarcação. Diante da perspectiva de significado aumento da demanda por essas embarcações e da mudança tecnológica para sistemas de propulsão diesel-elétricos, o trabalho também apresenta oportunidades e restrições econômicas ao desenvolvimento de máquinas e equipamentos nacionais que poderão equipar essas embarcações. O objetivo final desta pesquisa é selecionar concepções de projeto, maquinário e equipamentos a serem introduzidos no pacote de projeto e maquinário de uma embarcação de apoio de 4500 DWT.
Texeira, V. B.; Pires Jr., F.; Assis, L. F. (2012)
Proceeding of 24th International Congress on Waterborne Transportation, Shipbuilding and Offshore Constructions, SOBENA 2012 . Volume 1. SOBENA, SOBENA.
Assis, L. F. ; Pires Jr., F.; Silva, C. T.; Freire, R. M.; Baptista, M. T. p.; Portugal, B. P. (2012)
Proceeding of 24th International Congress on Waterborne Transportation, Shipbuilding and Offshore Constructions, SOBENA 2012 . Volume 1. SOBENA, SOBENA.
Os processos de montagem, pré-edificação e edificação de blocos podem ser considerados críticos para grande parte dos estaleiros de construção naval. Essas fases construtivas apresentam alta complexidade de programação, principalmente no caso de construção simultânea de navios com grande número de blocos de portes e conteúdos de trabalho diferentes. Além das restrições técnicas, que exigem que determinadas seqüências de atividades sejam respeitadas, o compartilhamento de recursos de movimentação é outro desafio para a gestão de processos. O presente trabalho apresenta um modelo de simulação de eventos discretos para facilitar a análise dos principais processos que ocorrem durante a construção simultânea de navios. O modelo desenvolvido proporciona ferramenta genérica de estudo do comportamento de sistemas, sendo possível adequá-lo a diferentes tipos de estaleiros, ou navios, bastando apenas alterar a base de dados acessados. O estudo pretende mostrar o potencial da técnica no suporte à tomada de decisões estratégicas, e no controle do desempenho de sistemas produtivos.
Conde, M.P.; F.C.M. Pires Jr. ; L.F. Assis (2012)
Proceeding of 24th International Congress on Waterborne Transportation, Shipbuilding and Offshore Constructions, SOBENA 2012 . Volume 1. SOBENA, SOBENA.
Caprace, J.-D. ; Freire, R M ; Assis, L. F. ; Pires, F. C. M ; Rigo, P. (2011)
Proceeding of the 22th Pan American Conference Of Naval Engineering - Maritime Transportation & Ports Engineering , Buenos Aires, Argentina.
Nowadays, shipyards are making huge effort to efficiently manage equipments and resources such as laborers, gantry cranes, transporters, steel and block stock yards, etc. Previously scheduling was manually performed by an experienced manager of a shipyard. But such a scenario leads to undesirably long times for producing scheduling results. In addition, the quality of the scheduling results was usually not optimal. To improve the overall process, Discrete Event Simulations (DES) have been developed and recently use in shipbuilding industry. The use of simulation-based design and virtual reality technologies leads to higher efficiency in terms of work strategy planning, and offers, as a result, significant productivity gains. It gives computer-supported answers to the major questions: when and where to produce what and with which resources depending on the availability and restrictions of resources and materials. The first part of the paper presents a multi-criteria analysis to select the most appropriate DES software for shipyards. Then, the second part of the paper shows production simulation model focusing on block erection stage. Two different blocks splitting are compared and then the results are discussed.
Caprace, J.-D.; Trevisani, C.; Rigo, P.; Pires, F. C. M. (2011)
Proceeding of the 10th International Conference on Computer and IT Applications in the Maritime Industries (COMPIT) .
Nowadays, shipyards are making every effort to efficiently manage equipments and resources such as labourers, gantry cranes, transporters, steel and block stock yards, etc. The block erection scheduling of a gantry crane has thus far been manually performed by a manager of a shipyard. Such a scenario leads to undesirably long times for producing scheduling results. In addition, the quality of the scheduling results may not be optimal. To improve the overall process, block erection discrete event simulations have been developed in this study by using techniques of optimization. The first results presented in this paper are promising even if some future work must be realized.
Pires Jr., F.; Assis, L. F. ; Rezende Filho, M. ; Vieira, C L B (2011)
Proceeding of International Conference on Computer Applications in Shipbuiding, ICCAS 2011 , Trieste. Royal Institution of Naval Architects - RINA, Royal Institution of Naval Architects - RINA.
The Brazilian shipbuilding industry is presently showing significant recovery prospects. However, there are some problems affecting this process. The high level of builder's risk perceived by the owners and, mainly, by banks, insurance companies and other stakeholders, is likely the most critical. The main instrument to keep the risk in acceptable levels is a strict control of the construction progress. However, some shipowners have been employing control systems that are excessively complex, detailed and expensive, but, at same time, not sufficiently effective. This paper presents the main characteristics of a computer system developed to provide a broad control over theconstruction progress and financial balance as well as a continuous risk assessment.
Pires, F. C. M.; Guimarães, L.F.; Almeida, M.F.; Fischer, R. (2011)
Proceeding of International Conference on Computer Applications in Shipbuilding, ICCAS 2011 , Trieste. Royal Institution of Naval Architects - RINA, Royal Institution of Naval Architects - RINA.
Pires, F. C. M.; Trevisani, C. (2010)
Proceeding of the 23 Congresso Nacional de Transporte Aquaviário, Construção Naval e Offshore (SOBENA) .
A Simulação de Processos vem trazendo benefícios voltados para a análise de gargalos, otimização da produção e utilização eficiente de recursos para setores, como por exemplo, indústrias aeronáutica e automobilística. O presente estudo classifica os estaleiros brasileiros em grupos de empresas em fase de planejamento do arranjo físico (ou de ampliação de oficinas), e em fase de operação (funcionamento). Foram levantadas questões relativas a cada tipo de estaleiro, que poderiam ser analisadas através de simulação, e descritos os principais processos construtivos. Exemplos de aplicações nacionais e internacionais no setor naval foram destacados, assim como foram ressaltados a evolução da técnica, e os programas (simuladores) disponíveis. Uma estrutura hierárquica é apresentada, contendo os critérios relativos ao fornecedor, ao programa (simulador) e ao usuário, de forma a facilitar a escolha do programa mais adequado ao perfil do estaleiro. Finalmente, como exemplos de aplicação, são apresentados estudos de caso: Pátio de armazenagem aço, Linha de fabricação de painéis planos e Montagem e Pré-edificação de anéis.
Pires, F. C. M., Schachter, R. D., Assis, L. F. (2008)
Proceeding of the 22 Congresso Nacional de Transporte Aquaviário, Construção Naval e Offshore (SOBENA) .
O presente trabalho apresenta uma análise de demandas para a indústria brasileira de construção naval, a partir da perspectiva do Programa de Engenharia Oceânica da COPPE/UFRJ. É feita uma discussão sobre as principais tendências internacionais nas áreas de gerenciamento de projetos, gestão de operações e projeto do produto, bem como perspectivas para indústria brasileira de construção naval. O trabalho também discute alguns resultados nas áreas de gerenciamento de projetos, projeto do navio orientado à construção, simulação de processos de construção naval e manufatura digital.
Souza, C. M.; Trevisani, C.; Freire, R.M.; Costermani, H.; Mendes, Y. (2008)
Proceeding of the 22 Congresso Nacional de Transporte Aquaviário, Construção Naval e Offshore (SOBENA) .
O trabalho desenvolvido apresenta a aplicação da simulação no planejamento e organização de estações de trabalho e na análise integrada de processos críticos como a montagem de blocos e edificação. Os modelos representam oficinas de um estaleiro hipotético dedicado à fabricação de navios tanque Suezmax. A metodologia desenvolvida pode fornecer suporte à tomada de decisões no que se refere ao planejamento da produção, dimensionamento de recursos e estabelecimento de regras de trabalho. A estrutura do corpo paralelo de um navio Suezmax típico foi modelada tridimensionalmente. Para cada peça da estrutura foi determinada identificação própria, permitindo o entendimento de suas necessidades e processos inerentes. Duas frentes de análise foram estabelecidas de forma independente. A primeira corresponde a modelos com diferentes configurações para a montagem de blocos e a segunda corresponde ao processo de edificação. O modelo de montagem de blocos avalia problemas de agrupamento de blocos em estações de trabalho específicas e de dimensionamento de estações de trabalho. No modelo de edificação foram avaliadas diferentes estratégias (anel, camada e piramidal), avaliando-se a utilização de recursos e tempos de produção. Em seguida, os modelos foram integrados. A integração permitiu verificar como as interferências entre as duas áreas consideradas podem alterar de forma relevante os cenários de produção.

Book Chapter

, Editor: Papanikolaou, A. Authors: Caprace, J.-D.; Rigo, P.; Sekulski, Z; Bayatfar, A.; Jaramillo, S. E. (2018) . Structural Design Optimization – Tools and Methodologies.
Volume 1, pages 1, Springer.
This chapter focuses on methodologies to perform ship structure optimization, decreasing steel weight and keeping the production cost at an acceptable level. Ship performance is always an important concern when a design is started, and should always be considered for new designs. This is in line with the evolution of ship classes and size. For this reason, several aspects are important to be taken into account within the optimization procedure and therefore, multi-objective optimization is the common route. This chapter outlines actual trends in optimization methodologies, comments on the quality assessment of the obtained Pareto solutions and describes modern tools used in/by the maritime industry (with focus on the LBR-5, BESST and HOLISHIP projects). The importance of consideration of risk assessment in the structural design optimization procedure (e.g. of a ship collision with an offshore structure) is also elaborated with a highlight on the Response Surface Method and its use in combination with optimization algorithms for ship and offshore structures in early design stages.
, Editors: Freng, J. C.; Jukes, P.; Sang, C. Y.. Authors: Praillon, J.; Cabos, C.; Caprace, J.-D. J. E. M.; Czaban, Z. J.; Peschmann, J.; Zanic, V. (2017) . Structural Design Methods and Documentation.
pages 1-12, John Wiley & Sons, Ltd. . John Wiley & Sons, Ltd. edition.
Ship design and production activities are strongly driven by a very competitive environment as well as a reduction of time to market. The use of computer tools is thus strongly needed but is subject to many constraints. This article aims to provide the reader with a global view of this topic.
, Edithors: Guedes, C. G.; Garbatov, Y.; Fonseca, N.; Teixeira, A.P. Authors: Rigo, P.; Caprace, J.-D. (2012) . Optimisation of ship structures.
Volume 2, pages 925-944, Taylor & Francis Ltd.
Limiting CO2 emissions is a great challenge being faced by society today. Society, through the United Nations Framework Convention on Climate Change (UNFCCC), and actors like the EU, is applying pressure on all industries, including the shipping industry, to reduce CO2 emissions. This paper presents a way to decrease the GHG emissions by ship scantling optimisation, i.e. decreasing steel weight and keeping the production cost at an acceptable level. The authors first review the links between “Design” and “Optimization” and secondly define the place of “Ship Structure Optimization” within the general framework of a “Ship Optimization”. Then, the LBR-5 ship structure optimisation software is presented. It is based on a convex lin-earization coupled with a dual approach and is based on a rational assessment of the ship structures behaviour. Few applications of structures optimization are then presented.
, Editors: Soares, C. G.; Das, P.K. Authors: Losseau, N.; Caprace, J.-D.; Rigo, P.; Fernandez, F. A. (2009) . Chapter 6: A data mining analysis to evaluate the additional workloads caused by welding distortions.
pages 365-370, Taylor & Francis Ltd.
The idea used to establish relations between those supplementary workloads and the residual welding distortions was to lead a statistical analysis based on the production data from a shipyard. This paper gathers the results of several analyses realised with the so called data mining technique.

Master Thesis

Vinicius Barreto Martins (2021). Master's thesis
Federal University of Rio de Janeiro, Rio de Janeiro.
Joice Fernandes Carrara (2020). Master's thesis
Federal University of Rio de Janeiro, Rio de Janeiro.
Brunna Fuoco Serpa Ribeiro (2020). Master's thesis
Federal University of Rio de Janeiro, Rio de Janeiro.
de Santana, Luiz Filipe Ferreira; (2019). Master's thesis
Federal University of Rio de Janeiro, Rio de Janeiro.
This paper presents the development of a discrete event simulation model for the logistic analysis of a system consisting of a maritime oil terminal, a refinery and its customers. The developed model was applied to study an existing system to demonstrate its diagnostic and prognostic capabilities. Each modeling step performed, the algorithmic structure of the elaborated model, it is programming in a simulation environment, the main key performance indicators (KPIs) for the analysis of the system and the results of the case study are presented and discussed.
Roldán León Ramiro Alejandro (2019). Master's thesis
Universidade Federal do Pará, Belem, Pará, Brazil.
Kelton Pimentel Guimarães (2019). Master's thesis
Universidade Federal do Rio de Janeiro.
Marcos Thadeu Palmeira Baptista (2018). Master's thesis
Federal University of Rio de Janeiro.
Semih Yellice (2018). Master's thesis
Federal University of Rio de Janeiro.
Marcio Fleming (2018). Master's thesis
Federal University of Rio de Janeiro.
Marcelo Costa Alves (2017). Master's thesis
Federal University of Rio de Janeiro.
In this paper will be raised and ranked the crisis situations frequently occurring in the activity of entering the port, in the view of the respondents, to the preparation of the study. Using a simulated exercise, the bridge team's decision-making and reasoning, in the face of unexpected situations, could be recorded and the results compared to a table drawn up by experts from the National Council of Pilotage (CONAPRA) from past experiences. Therefore, this research outlines initial evidence within the methodology applied in the universe searched. In view of the proposed activity, aspects of the cognitive activity were identified for accomplishing the task and collected elements that make it possible to say that the experience of those involved was the primordial factor in the success of the execution of the maneuvers
Leonardo Sousa Soares (2017). Master's thesis
Federal University of Rio de Janeiro.
The Electronic Chart Display and Information System (ECDIS) has become a key element in ships' bridge and it is of great importance for the officer to interact well with the system to maintain safety of navigation. The objective of the study is to analyze the shared cognitive system between the operator and the ECDIS system during navigation from the perspective of Resilience Engineering. The data for analysis were obtained through simulation. For the preparation of the scenario for simulation, interviews with specialists were carried out and documents were analyzed on the technology in question, as well as accident reports. As stated in the International Convention on Standards of Training, Certification and Watchkeeping for Seafarers (STCW), Situational Awareness (SA) when using ECDIS is a requirement. Therefore the first approach of the work was to try to measure the SA of officer according to Endsley's theory. For that, a questionnaire was applied to the simulation participants for objective measurement. The results indicated an overall CS level of 41% In addition, the verbal protocol was recorded through the think aloud process and functional cognitive models were used to understand the participants' mental processes during the task and the results showed that difficulties faced can lead to goal changes, but it is still possible maintain control and thus safety of navigation. The results suggest that the vision for ix these models can be complete by being able to represent and consider the aspects of time and objectives of the operator
Rafael Basílio da Silva (2017). Master's thesis
Federal University of Rio de Janeiro, Rio de Janeiro.
Logistics plays a fundamental role in the petroleum and oil industry, since large distances between offshore units and its onshore supply base demand an efficient supply chain. In this scenario, oil companies use huge infrastructure to service, maintain and develop operations of offshore units, composed by airports, ports, hubs, warehouses, specialized vessels, among other resources. Weather conditions, vessels off-hire rates and vessel waiting time to operate offshore units are the more sensitive variables that affect offshore supply operations. In this context, the present work aims to find the ideal amount of supply vessels necessary for the logistics of offshore cargo transportation to fulfill its function without affecting the service level demanded. In this study, resource costs perspective will be incorporated for analysis purposes.
Rafael Fischer Dutra e Mello dos Santos (2017). Master's thesis
Federal University of Rio de Janeiro.
The global shipping industry is under constant pressure to develop sustainable alternatives related to the emission of greenhouse gases, which is directly related to the fuel consumption. One of the main problems of vessel’s performance is consequence of deterioration of the hull and propeller. Based on this, it is necessary to predict the best maintenance interval without increasing resource spending. The sailing data was analyzed through data mining method, from the pre-processing of the database to the regression and classification analyzes. The result is a model of hull and propeller maintenance planning that identifies the best interval for execution of interventions in order to avoid a significant increase in ship consumption. The study demonstrates that it is possible to improve the efficiency of a fleet by means of this model developed from the sailing data already available in the daily routine of the vessels.
Gormus, D. M. (2016). Master's thesis
Federal University of Rio de Janeiro.
Logistics of offshore production sites is rising in importance due to massive increase in exploration and production of oil and gas. In addition to this, the number of production sites and number of the ships that are working in these fields such as crude oil tankers and Platform Supply Vessels (PSV) are increasing significantly with the complexity of logistics operation process. Although there are some researches about fleet efficiency of supply vessel in offshore logistics, there are only few studies simulating the complete supply chain management of the offshore production fields. This thesis covers the investigation of the logistics of supplies and transportation of oil from/to offshore production sites around Brazilian coasts. Besides, it proposes an option to extract relevant information from an AIS (Automatic Identification System) database and use this information to create the inputs of a stochastic simulation about logistics of offshore production sites. A database which contains 6 months of AIS tracking data for 90 ships has been analyzed. An algorithm has been developed to be able to identify the behavior and role of each PSV and each crude oil tanker in the studied offshore supply chain. Offshore logistics activities in Campos Basin, i.e one of important coastal sedimentary basins of Brazil, has been modeled by using Discrete Event Simulation (DES) methodology. It includes 5 ports, 15 crude oil tankers, 23 PSVs and 38 offshore production platforms such as FPSO (Floating Production, Storage and Offloading), fixed platforms and SS (Semi-submersibles). Several distributions have been extracted for each type of ship and operation profilethen used as input variables for the simulation. Following the implementation of stochastic parameters into the model, the simulation is repeated until it reaches to convergence. The preliminary results show a good accordance between simulation outputs and measured data from AIS database. However, future work is required to improve the offshore supply chain simulation and robustness of the simulation. Optimization is also a possible improvement for the next future. We suggest that DES is a useful tool to make precise analyses and decisions in offshore logistics applications.
Selamoglu, A. (2016). Master's thesis
Federal University of Rio de Janeiro.
Ship building involves complicated production processes in a highly competitive environment. Therefore improving and obtaining more efficient production facilities is getting more and more important. This fact results in the increase of usage of simulation and optimization tools in the industry. However, coupling these two fields of applications is still not common. This paper proposes a new application by coupling two commercial tools present in the market, QUEST by Delmia for Discrete Event Simulation (DES) and MODEFRONTIER for optimization in a case of improving a steel stockyard in a shipyard. A multi-objective optimization is carried out by taking three design variables and aiming to optimize the objective functions. Number of steel plate piles in stockyard, steel plate capacity of each pile and frequency of steel plate arrival to shipyard are selected as design variables. The objectives are minimizing the area used for stocking and minimizing the Work In Progress (WIP). It is suggested that shipyards with different steel processing capacities would require different sizes of stockyards and different frequencies of incoming steel plates. Therefore a layout plan should be made based on running optimization tasks. The findings provide that production cost can be reduced by carrying out proper planning. The fundamental knowledge of coupling optimization and stochastic simulation tools may result in significant reduction of production costs by minimizing storing area and work in progress. The new solution is also valid for other fields of ship building such as block erection or steel processing and may be modified for further applications.
In 2014, the ship world fleet grew by 3.5% and reached a total of 1.69 billion DWT that consisted of 89 464 vessels including bulk carriers, oil tankers and container carriers. Consequently, it produces a growth of fuel consumption and Green House Gas (GHG) emissions at sea. Therefore, the concerns of ship owners to implement alternatives solutions to improve the fleet efficiencies are growing. Although, ship owners are facing barriers to implement energy efficiency technologies mainly due to reliability, financial and economic constraints as well as complexity of change. Therefore, it is important to undertake actions that will optimize actual system with small investments. Nowadays, several ship owners use on-board data measurements systems that collect navigation and propulsion information of their ships. The information gathered is available to assess the performance of their fleets. This thesis develops a mathematical model to assess fleet ship performance using a database of 13 ships with 6844 daily navigation reports. This model use criteria based on speed, ship delivery date, gross tonnage, specific fuel oil consumption, admiralty coefficient, emissions quantity (CO2, SOX and NOX), ship work, and cargo quantity. Multi Criteria Decision Analysis (MCDA) and Data Envelopment Analysis (DEA) are combined in order to assist the ship owner in the improvement of the performance of their fleet. The outcomes give an efficiency outranking of the ships inside a fleet in a way that best and worst ships are identified at any moment. The results suggest that this new methodology can provide a multicriteria decision framework to ship owners avoiding engineer's subjectivity. These findings offer a new way to address efficiency and performance in ship management.
Rasih Onur Süzen (2015). Master's thesis
Federal University of Rio de Janeiro.
Efficiency improvement in container terminal operations can lead to increase service capacity, reduce berthing time and operational expenses of ports. Moreover, being faster in ports allows a ship to transit at lower speeds (slow steaming) thus to save fuel as well as to reduce emissions, or else ship can sail at same speed to have higher annual cargo capacity and income. Despite that there being researches about existing container terminal productivity assessment, no papers analyzing port efficiency of a new bay plan design of a container ship stochastically have been published. This thesis proposes a productivity analysis of a new bay plan design which intends to be faster during loading and unloading at container terminals. The operational efficiency of a container terminal is investigated for various conditions and its effect on berthing time is reviewed. Port productivity, i.e. the time needed to move a selected number of containers, is assessed using a Discrete Event Simulation methodology. A fully parametrical port simulation model is created and calibrated based on a 7 months statistical data set of a real container terminal. The uncertainties and unpredictable events i.e. several types of delays related to operations are implemented using semi-random numbers. Following the description of the stochastic parameters included in the model, the simulation is repeated until sufficiently large sets of iterations are available for statistical analysis. Then, the dispersion of results regarding the port productivity are discussed and compared to measured data. Finally, we obtain the results concerning efficiency of a new bay plan where various conditions, such as the high/low tide, higher/lower crane speeds and multiple crane usage, are considered We suggest that DES is one of the most precise analysis and decision assistance tool to accomplish operational performance studies for new bay plans and container terminals.
Orlando José Teixeira Fernandes (2015). Master's thesis
Federal University of Rio de Janeiro.
The Shipbuilding Industry in general doesn’t use methods and indicators to track and control projects, as others sectors do. This Project presents a case study to introduce a method as an alternative to the usual method used in this Industry. Both methods are applied to compare the results. The usual method utilizes Work Breakdown Structure suitable for standard budget, based on Order Standard (OS-5) of Merchant Marine Fund. The Work Breakdown Structure groups the vessel construction elements according to Order of Service-5 definitions. The performance measurement is based on the comparison between performed and budgeted. The proposed method also uses Work Breakdown Structure, but enriched by the Precedence Network of project activities. In this model, the performance measurement is analyzed by Earned Value Management, one of the most powerful tools to structured assessment of project performance. To compare the results, each method is analyzed, evaluating the resources of measuring progress and of cost and schedule projections. In addition to that, is observed how this resources support to identify problems and to improve the project performance, by evaluating the work and deadline of project activities. The proposed model can be used to support decision-making by managers involved in the project.
Larissa Prates Guimarães Petroianu (2014). Master's thesis
Universidade Federal do Rio de Janeiro.
This paper shows how Lean Manufacturing may assist in process improvement and restructuring of Brazilian shipbuilding that currently has high demand but low capacity to meet it and weak competitiveness. The main goal of Lean is to increase productivity and reduce costs through the elimination of unnecessary operations, considered as waste. The concept is already used in different industrial segments and, despite having been developed for mass production processes, with some adaptations, it has also proven effectiveness in other types of industry, such as object-oriented, like shipbuilding. The dissertation examines benefits that Lean Manufacturing can provide to shipbuilding's process improvement and how to implement them, focusing on a case study based on a line of block construction in a medium sized shipyard. Three scenarios were simulated in Arena software, the existing situation, the same stabilized and a new restructuration suggestion. Through simulation, its results and possible benefits were measured.
Texeira, V. B. (2011). Master's thesis
Federal University of Rio de Janeiro, Rio de Janeiro.
This work outlines a laytime behavior analysis based on a computer supported simulation model for brazilian crude oil transhipment operations carried out under Baia da Ilha Grande Tanker Terminal (TEBIG) influence zone. A laytime comparison is presented considering transhipments done via terminal only and also considering same tanker arrival pattern but with transhipment operations to be executed also via ship-to-ship operation at a support anchorage area under same TEBIG influence area. The simulation model has considered as input a real data base with regards to tanker arrivals to Baia de Ilha Grande Tanker Terminal which is not a public terminal and is managed by Petrobras Transporte S.A. – Transpetro. To the same extent the model aims based on the tanker arrivals real data base and also on further assumptions to the base case scenario to present laytime and export volumes behavior with and without having a support anchorage area for ship-to-ship operations. The use of transhipment has been shown effective alternative to reducing the laytime and giving increased capacity to export volumes.
Conde, M.P. (2011). Master's thesis
Federal University of Rio de Janeiro.
The aim of this assignment is to analyze the oceanic terminal PRA-1 operation with the development of a simulation model using the ARENA software. Allowing the planning, in a short and long time, and investments to ensure the operation in production areas. For a better comprehension, the assignment starts with the problem contextualization. In this phase is made a reflection about the reason and the development story of the petroleum extraction industry in Brazil. This contextualization ends with an analysis of the reasons why Petrobras decided to install an oceanicterminal at Bacia de Campos. After that, the assignment presents the bibliographic revision that was made a broad survey about logistics works, distribution and simulation techniques. Next, the assignment presents the problem description of used methodology and advanced on petroleum field studies which use the oceanic terminal PRA-1 for production flow. In this moment the assignment presents the Petrobras structure and the agents that participate on PDET. After that, the assignment presents the developed of the simulation model for FSO-CIMA operaction. In the end the assignment presents the results and their utility, determining the best moment for the beginning of the monobuoy operational, which is an important part of the terminal.
Clarice Trevisani da Silva (2010). Master's thesis
Universidade Federal do Rio de Janeiro.
This study presents the Discrete Event Simulation as a State of the Art highlighting the various sectors that use this technique, and it presents the development of the tool. A hierarchical structure of criteria is presented to facilitate the appropriate choice of computational simulator for the corporation. Shipyards were classified into groups that are in the planning stages of the physical arrangement (or extension of the workshops), and groups that are in operational phase. According to the profile of the shipyard, and its difficulties, the Simulation of Industrial Processes was presented as a way to assist the processing and analysis of issues relevant to the type of the organization. We describe the main processes of Shipbuilding and cited examples of the use of this technology in specific constructive stages. Finally we present three case studies from developing models of Steel Sock Yard, Assembly, Painting and Pre-erections blocks, and Panel Line. These case studies highlight the methodology of a simulation project, the requirements for the modelling and the results that can be obtained.
Alessandro Barile (2009). Master's thesis
Federal University of Rio de Janeiro.
This work describes the development of a computer program for Mono Hull Planning Boats Structural Design, that allows the interactive action of the designer, computing and drafting all structural elements, such as plates and stiffeners, based on Classification Society American Bureau of Shipping (ABS), “Guide for Building and Classing High-Speed Craft” of October 2001”. For a given vessel, the program imports its geometry, allows for its compartmentation, calculates local pressures imposed to the structure, plates thicknesses, longitudinal and transverse structural elements, bulkheads stiffeners, acting bending moment along the entire vessel, section modulus and inertias required and offered for the vessel’s sections, approximates calculated plate thicknesses to standard thicknesses, checks longitudinal elements for buckling stability and at the end calculates the weight and center of gravity of the designed structure. The program was developed to be interactively user friendly, with screens for straight forward operation. The commands are designed for logical choices of action and results, workable by simple mouse clicks. At the end of calculations, the program generates a report with the results of all calculations performed.

PhD Thesis

Cepeda, Maricruz Fun Sang (2022). PhD thesis
Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
Automatic Identification System (AIS) data records a high quantity of information regarding the safety and security of ships and port facilities in the international maritime transport sector. However, the big databases are not only useful for these safety functions. It can also be helpful for other areas in maritime traffic, such as reducing environmental impacts, improving logistics, and examining compliance with current International Maritime Organization (IMO) regulations. The purpose of this research is to provide a ship emission inventory and an assessment of the efficiency of several technical options to reduce the impact of ocean-going ships on the atmosphere and climate. In other words, this work aims to examine how technological improvements and policy strategies might help reducing emissions from international shipping in the future. Input data for these approaches were collected from different sources and maritime databases such as the worldwide ship fleet register and AIS database. The present proposal assess how possible improvements in technology or alternative energies and fuels could impact the future evolution of ship emissions. Three cases of studies are developed to estimate ship emissions based on AIS. The last case study added an application of scenarios, and it defined considering a combination of technologies and several future ship traffic demand scenarios mainly determined by the economic growth. The prediction is for 2050. The result shows how alternative energies and fuels could impact almost 50% of most minor ship emissions, concurrently implementing newly introduced international policy measures. In conclusion, a better quantitative understanding of the efficiency and impact of the technical alternative to reduce ship emissions may help the decision-makers to improve their strategies.
Cassiano Marins de Souza (2009). PhD thesis
Universidade Federal do Rio de Janeiro.
The main purpose of this work is a joint approach to innovative concepts, techniques and tools under a broader scientific perspective and moreover with an original application to the shipbuilding industry. Putting together Technology Group concept, Artificial Inteligence and Discrete Event simulation techniques is a relevant contribution to shipbuilding planning, scheduling and control functions. This contribution is able to lead to significant efficiency gains and originating an upgrade on productivity levels, mainly considering Brazilian shipbuilding environment. To take advantage from concepts and tools mentioned above it is necessary that production performance indicators be controlled in an effective way. A production control system was then developed to monitor shipbuilding activities on different areas of a shipyard. With this system it is possible to identify impacts from planning and scheduling actions and also feed up replanning activities or newbuilding planning.

Technical Report

Victor Mello Callil (2020). Technical Report
Universidade Federal do Rio de Janeiro, Rio de Janeiro. Trabalho de Conclusão de Curso (Graduação em Engenharia Naval e Oceânica).
Worldwide, shipyards manufacturers of cruise and roll-on/roll-off vessels worldwide have adopted steel-aluminum joints made by the explosion method to fasten the steel plate of the hull to the aluminum plates of the decks. Although this methodology is used in the naval field, it presents weak mechanical properties, CO2 emission, high-cost production, and low manufacturing safety. The purpose of this work is to analyze the effects of process parameters joining the dissimilar materials AA6082 and AISI316 by Friction Stir Welding (FSW) and to compare them to the mechanical properties obtained by the explosion bonding technique. Both the aluminum and steel plates were 300 x 150 x 6 mm, laid out in butt-joint configuration with tool displaced towards the aluminum sheet in order to prevent wear of the probe. The best results were obtained for an offset of 0.1 mm with a 300 RPM rotation speed, 2.0 mm/s translation speed, 12.5 KN axial force, and 1o tilt angle. The ultimate tensile strength achieved 62.73% of the aluminum base material, while the maximum tensile strength of explosion welding corresponds to 24.19% of the aluminum plate. These results may help improve the manufacturing techniques of marine structures, with FSW as one of the possible future joining techniques of dissimilar materials.