References of "Bair, Frédéric"
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See detailEarly Structural Assessment and Optimisation of Passenger Ships
Caprace, Jean-David ULg; Bair, Frédéric ULg; Rigo, Philippe ULg

in Procceding of the International Conference on Design and Operation of Passenger Ships (2011, February 23)

A multi-criteria optimisation of a passenger ship is conducted in this paper. Minimum production cost and minimum steel weight are the both objective studied. Moreover the study answers to the following ... [more ▼]

A multi-criteria optimisation of a passenger ship is conducted in this paper. Minimum production cost and minimum steel weight are the both objective studied. Moreover the study answers to the following question: "From when will the higher costs of high tensile steel should be offset by a gain of steel weight?". For a passenger ship, a significant reduction of the steel weight, for a controlled raise of the gravity centre, should lead either to a reduction of fuel consumption either to an additional deck, which for a ship owner means a faster return on investment. Pareto frontiers are obtained and results are validated by classification rules. [less ▲]

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See detailMulti-criterion Scantling Optimisation of Cruise Ships
Caprace, Jean-David ULg; Bair, Frédéric ULg; Rigo, Philippe ULg

in Ship Technology Research = Schiffstechnik (2010), 57(3), 56-64

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 ... [more ▼]

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 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 passenger ship 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 optimizing 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. [less ▲]

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See detailScantling Multi-objective Optimisation of a LNG Carrier
Caprace, Jean-David ULg; Bair, Frédéric ULg; Rigo, Philippe ULg

in Marine Structures (2010), 23(3), 288-302

Numerous real-world problems relating to ship design are characterized by many alternatives. Moreover in the scantling design, minimum production cost, minimum weight and maximum moment of inertia ... [more ▼]

Numerous real-world problems relating to ship design are characterized by many alternatives. Moreover in the scantling design, minimum production cost, minimum weight and maximum moment of inertia (stiffness) are conflicting objectives. Ship design is a complex endeavour requiring the 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 were made to the LBR-5 software to optimise 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 LNG carrier is conducted in this paper to illustrate the analysis process. Pareto frontiers are obtained and 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. [less ▲]

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See detailLeast Weight and Least Cost Optimisation of a Passenger Vessel
Caprace, Jean-David ULg; Bair, Frédéric ULg; Rigo, Philippe ULg

in Mathematical Modelling in Civil Engineering (2010), (2), 17-26

In the scantling design of a passenger ship, minimum production cost, minimum weight and maximum moment of inertia (stiffness) are conflicting objectives. For that purpose, recent improvements were made ... [more ▼]

In the scantling design of a passenger ship, minimum production cost, minimum weight and maximum moment of inertia (stiffness) are conflicting objectives. For that purpose, recent improvements were 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 [less ▲]

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See detailMulti-criterion Scantling Optimisation of Passenger Ships
Caprace, Jean-David ULg; Bair, Frédéric ULg; Rigo, Philippe ULg

in 9th International Conference on Computer Applications and Information Technology in the Maritime Industries (2010, April 12)

In the scantling design of a passenger ship, minimum production cost, minimum weight and maximum moment of inertia (stiffness) are conflicting objectives. For that purpose, recent improvements were made ... [more ▼]

In the scantling design of a passenger ship, minimum production cost, minimum weight and maximum moment of inertia (stiffness) are conflicting objectives. For that purpose, recent improvements were 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. [less ▲]

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See detailLogiciel Eol - Optimisation des mats d’éoliennes terrestres – (Etudes complémentaires)
Rigo, Philippe ULg; Thiry, Arnaud ULg; Bair, Frédéric ULg

Report (2009)

Rapport technique relatifs a des etudes complementaires sur l'optimisation des mats d'éoliennes

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See detailTools for early design stage: presentation of LBR-5 Software
Rigo, Philippe ULg; Bair, Frédéric ULg; Caprace, Jean-David ULg et al

in Zanic, Vedran; Andric, Jerolim (Eds.) Proceedings of IMPROVE Final Workshop (2009, September)

LBR-5 is a tool for early design stage. Taking into account numerous kinds of constraints – structural, geometrical, etc. – an optimum scantling can quickly been found. In the framework of IMPROVE ... [more ▼]

LBR-5 is a tool for early design stage. Taking into account numerous kinds of constraints – structural, geometrical, etc. – an optimum scantling can quickly been found. In the framework of IMPROVE European project many new modules have been implemented to increase the quality of the optimised scantling. Mainly 6 major changes have been brought: implementation of a sloshing module, a fatigue module, a multi-structure module, a multi-materials module, a life cycle cost module and finally a vibration module. Tests to validate these modules have been carried out on the three ships studied in the IMPROVE project: a LNG, a Chemical Tanker and a ROPAX. [less ▲]

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See detailProduction, Operation and Robustness Module
Caprace, Jean-David ULg; Bair, Frédéric ULg; Hübler, Michael et al

(2009, September)

Nowadays, simulation and Life Cycle Cost (LCC) assessment becomes more and more important in shipbuilding industry. In order to survive in the competitive market environment, manufacturers now have to ... [more ▼]

Nowadays, simulation and Life Cycle Cost (LCC) assessment becomes more and more important in shipbuilding industry. In order to survive in the competitive market environment, manufacturers now have to consider reducing the cost of the entire life cycle of a product, called LCC. This research was initiated with the idea of developing a methodology/framework to be able to assess the life cycle cost/earning of production and maintenance/repair with respect to the scantlings structural optimization variables to be used during the conceptual ship design stage. Three main modules as been implemented during this project: A life cycle cost/earning of production and maintenance/repair, a detailed Discrete Event Simulation (DES) for production and scheduling and a design robustness of the structural solution related to various fabrication and operational parameters. These three modules as well as the main results are briefly presented here. [less ▲]

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See detailLNG carrier- Structural design aspects
Amrane, Amirouche ULg; Constantinescu, Adrien; Bair, Frédéric ULg et al

in IMPROVE Workshop (EU Project FP6 n°031382), DUBROVNIK 17-18 Sept. 2009, Croatia, Editor V. Zanic – Univ. of Zagreb, pp90-95 (Vol I) (2009, September)

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See detailOptiView − A Powerful and Flexible Decision Tool Optimising Space Allocation in Shipyard Workshops
Caprace, Jean-David ULg; Bair, Frédéric ULg; Losseau, Nicolas ULg et al

in Conference on Computer Applications and Information Technology in the Maritime Industries (COMPIT) (2008, May)

This paper presents new developments to maximize the number of ship blocks and ship sections produced in various workshops of shipyards during a certain time window. The visualization tool OptiView® was ... [more ▼]

This paper presents new developments to maximize the number of ship blocks and ship sections produced in various workshops of shipyards during a certain time window. The visualization tool OptiView® was developed to support users to improve the space utilization and workshop productivity. The software is coupled with a heuristic optimisation solver. The paper describes the approach to the space allocation problem and gives three application examples. [less ▲]

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See detailA Data Mining Analysis Applied to a Straightening Process Database
Caprace, Jean-David ULg; Losseau, N.; Bair, Frédéric ULg et al

in Ship Technology Research = Schiffstechnik (2007), 54(4), 177-183

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See detailA Data Mining Analysis Applied to a Straightening Process Database
Caprace, Jean-David ULg; Losseau, Nicolas; Bair, Frédéric ULg et al

in Ship Technology Research = Schiffstechnik (2007), 54(4), 177-183

The complexity of modern manufacturing processes in a highly competitive environment forces the manufacturers to invest massively in automation and monitoring systems. The large data flows from these new ... [more ▼]

The complexity of modern manufacturing processes in a highly competitive environment forces the manufacturers to invest massively in automation and monitoring systems. The large data flows from these new installations are sources of valuable and hidden knowledge that is so far hardly used. Data mining methods through integrated data analysis tools give a solution to this situation, allowing easy retrieval of knowledge starting from a data base. This is also a unique opportunity to learn faster about the process and to detect hidden and complex relationships between parameters involved. Within this framework we have decided to apply this data analysis method to the straightening process in shipbuilding. We refer to Caprace et al. (2007) for additional illustrations. In shipbuilding, the assembly of elements by welding involves temperature gradients within the ma- terial. These cause deformations which sometimes have to be reduced to obtain an acceptable surface flatness. The straightening process to eliminate these distortions for esthetical or functional reasons is labour intensive. Estimating the straightening impact on the production workload is interesting in the context of production simulation, cost assessment of ship hull, structure optimization, design for production, etc. To reach these objectives, the idea was to elaborate, through a data mining approach, a formula linking the straightening cost to the sections scantlings (plate thickness, dimension and inter-distance of longitudinal stiffeners, dimension and inter-distance of transversal frames) and to other section characteristics. This paper describes each stage of the methodology: data description, analysis of data quality, data exploration and finally choice of discriminatory attributes and the generation of the data-driven models. [less ▲]

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See detailA Data Mining Analysis Applied to a Straightening Process Database
Caprace, Jean-David ULg; Losseau, Nicolas ULg; Archambeau, Dominique et al

in Conference on Computer Applications and Information Technology in the Maritime Industries (COMPIT) (2007, April)

The paper presents the results of a data mining analysis aiming to improve the cost knowledge of the labour intensive straightening process. The data mining approach yields a formula linking the ... [more ▼]

The paper presents the results of a data mining analysis aiming to improve the cost knowledge of the labour intensive straightening process. The data mining approach yields a formula linking the straightening cost to the sections scantlings (plate thickness, dimension and inter-distance of longitudinal stiffeners, dimension and inter-distance of transversal frames) and to other section characteristics. [less ▲]

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See detailMinimization of Production Cost by use of an Automatic Cost Assessment Method and Simulation
Caprace, Jean-David ULg; Bair, Frédéric ULg; Losseau, Nicolas ULg et al

in The Euro-Asia Maritime Network (EAMARNET) (2007, January)

This paper will present different ways to minimize cost in shipbuilding industry. Amongst them we have the production simulation methods, the cost assessment methods and the optimization methods. Nowadays ... [more ▼]

This paper will present different ways to minimize cost in shipbuilding industry. Amongst them we have the production simulation methods, the cost assessment methods and the optimization methods. Nowadays, cost assessment is a key task of an integrated ship design. The various methods to estimate the production cost differ with the known information (input data). The less information is detailed, the earlier a method can be used in the design process. The more information is used, the better we can assess the differences between design alternatives. The methods presented here and the “design for production” concept promise to increase the productivity trough the following points: a more accurate cost estimation, an improvement in the deadlines planning and the production schedule, a progress in distribution of the workload between the various production workshops, a better knowledge of the individual costs that will permit to reduce the global cost. In order to illustrate our work, we present in this paper three methods to decrease the global cost of a ship. [less ▲]

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See detailSIMULATION AND OPTIMIZATION OF A SHIPBUILING WORKSHOP
Bair, Frédéric ULg; Langer, Yves; Richir, Thomas et al

in ICCC Bexi Conference (2006, June)

This study concerns the simulation of a shipbuilding workshop, and its optimization to improve its productivity. Usually, simulation is used to improve efficiency but this optimization is often done ... [more ▼]

This study concerns the simulation of a shipbuilding workshop, and its optimization to improve its productivity. Usually, simulation is used to improve efficiency but this optimization is often done manually, particularly for shipbuilding workshop. This is due to the particularity of pieces to be manufactured: almost each of them is different and required thus particular operations. The automation is not so much present as, for example, in automotive industry. In spite of high CPU time for that kind of simulation, we will try to use optimization methods to improve productivity. Algorithm used is a genetic algorithm. [less ▲]

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See detailModélisation, Simulation et Optimisation d'un Atelier de Construction Navale
Bair, Frédéric ULg; Langer, Yves; Rigo, Philippe ULg

in 6ème Conférence Francophone de MOdélisation et SIMulation - MOSIM, Maroc (2006)

This study is about the simulation of a shipbuilding workshop, and its optimization in order to improve its productivity. The objective is to model precisely a complex workshop and to evaluate ... [more ▼]

This study is about the simulation of a shipbuilding workshop, and its optimization in order to improve its productivity. The objective is to model precisely a complex workshop and to evaluate possibilities to automate the optimization. The virtual model developed will be coupled with a genetic algorithm. [less ▲]

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See detailOptimization of Surface Utilization Using Heuristic Approaches
Langer, Yves; Bay, Maud ULg; Crama, Yves ULg et al

in Ship Technology Research = Schiffstechnik (2005), 52(3), 141-147

We present a scheduling problem that arises in factories producing large building blocks. This is a three dimensional bin-packing problem with two spatial dimensions and a time dimension. We propose an ... [more ▼]

We present a scheduling problem that arises in factories producing large building blocks. This is a three dimensional bin-packing problem with two spatial dimensions and a time dimension. We propose an algorithm based on the guided local search heuristic of Faroe and al. (Informs Journal of Computing,vol.15, 2003). The algorithm is especially developped to consider real-life issues. Finally the algorithm is applied on an industrial problem and shows excellent performances in speed and quality of the solution. [less ▲]

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See detailOptimization of Surface Allocation using Heuristic Approaches
Langer, Yves; Bay, Maud ULg; Crama, Yves ULg et al

in COMPIT 2005 , Hambourg, Germany (2005, May)

In this paper, we present a scheduling problem that arises in factories producing large building blocks (in our case, a shipyard workshop producing prefabricated keel elements). The factory is divided in ... [more ▼]

In this paper, we present a scheduling problem that arises in factories producing large building blocks (in our case, a shipyard workshop producing prefabricated keel elements). The factory is divided in several equal size areas. The blocks produced in the factory are very large, and, once a building block is placed in the factory, it cannot be moved until all processes on the building block are finished. The blocks cannot overlap. The objective is to maximize the number of building blocks produced in the factory during a certain time window. To solve this problem, we propose heuristics inspired by techniques initially developed for the three-dimensional bin packing problem, e.g. Faroe and al. (2003), since constraints for both problems are quite similar. Starting from an unfeasible solution, where blocks can overlap, a Guided Local Search (GLS) heuristic is used to minimize the sum of total overlap. If a solution with zero overlap is found, then it is a feasible solution; otherwise the block with the biggest overlap is removed and the procedure is restarted. The GLS algorithm has been improved by Fast Local Search (FST) tech- niques in order to speed up convergence to a local minimum. Additionally, neighborhoods are restricted to their smallest size so as to allow their evaluation in polynomial-time. In a last step, we explain the additional real-life issues arising in the industrial application and how firm-specific constraints can be conveniently considered by the model. [less ▲]

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See detailModelling, Simulation and Optimization of a Shipbuilding Workshop
Bair, Frédéric ULg; Langer, Yves; Caprace, Jean-David ULg et al

in COMPIT'2005 -Conference on Computer Applications and Information Technology in the Maritime Industries, Hamburg (2005, May)

Detailed reference viewed: 122 (31 ULg)