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See detailAn Optimization Method for the Design of Physical and Maxwellian Absorbers
Meys, B.; Henrotte, F.; Geuzaine, Christophe ULg et al

in IEEE Transactions on Magnetics (1999), 35(3), 1430--1433

Detailed reference viewed: 11 (0 ULg)
Peer Reviewed
See detailAn Optimization Method for the Design of Physical and Maxwellian Absorbers
Meys, B.; Henrotte, F.; Geuzaine, Christophe ULg et al

in Proceedings of the Eighth Biennal IEEE Conference on Electromagnetic Field Computation (1998)

Detailed reference viewed: 9 (1 ULg)
See detailOptimization Methods
Fleury, Claude ULg; Braibant, V.

in Haug, Edward J. (Ed.) Computer Aided Analysis and Optimization of Mechanical System Dynamics: Computer aided analysis and optimization of mechanical system dynamics: proceedings of the NATO advanced study institute on computer aided analysis and optimization of mechanical system dynamics (1984)

Detailed reference viewed: 13 (2 ULg)
See detailOptimization methods for inverse modeling of forming processes
Ponthot, Jean-Philippe ULg; KLEINERMANN, J.-P.

in Habraken, Anne (Ed.) Proceedings of the Fourth International ESAFORM Conference on Material Forming (2001)

Detailed reference viewed: 9 (1 ULg)
See detailOptimization Methods for Inverse Problems in Large Strain Plasticity
KLEINERMANN, J. P.; Ponthot, Jean-Philippe ULg

in 1st CanCNSM – Canadian Conference on Nonlinear Solid Mechanics (1999)

Detailed reference viewed: 28 (1 ULg)
See detailOptimization Methods for Inverse Problems in Metal Forming Simulation
KLEINERMANN, J. P.; Ponthot, Jean-Philippe ULg

in Proceedings of SACAM 2000, International Conference on Applied Mechanics (2000)

Detailed reference viewed: 14 (1 ULg)
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Peer Reviewed
See detailOptimization Methods for Inverse Problems in Metal Forming Simulation
Kleinermann, Jean-Pascal; Ponthot, Jean-Philippe ULg

in STEELS-Mechanical Technology (2001)

Detailed reference viewed: 36 (1 ULg)
See detailOptimization methods for parameter identification of constitutive models in finite viscoplasticity and damage
Stainier, Laurent ULg; KLEINERMANN, J.-P.; Ponthot, Jean-Philippe ULg

in Proceedings of PLASTICITY 2003 (2003)

Detailed reference viewed: 5 (1 ULg)
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See detailOptimization Methods for the design and production of Naval Structures
Bay, Maud ULg

Doctoral thesis (2011)

In the past decades the marine industry has undergone significant evolution and the production of large passenger ships faced dramatic changes. The size, the complexity and the security standards of the ... [more ▼]

In the past decades the marine industry has undergone significant evolution and the production of large passenger ships faced dramatic changes. The size, the complexity and the security standards of the ships have increased and the ship-owners have become less and less willing to wait once the order is placed. In the meantime, due to growing intense competition, the shipyards have had to improve their efficiency and master their production costs: they progressively moved from manufacture to automated production processes. As a consequence, the shipyards have now to meet this difficult challenge: produce more complex ships, cheaper and faster. In the first part of the thesis we consider the structural optimization problem that arises in the early design phase of a project. Given a vessel overall dimensions and form, structural optimization consists in defining the scantling of the structure’s constitutive elements so as to minimize its total weight or cost, while taking weight, robustness and security issues into account. Designers have to make the most adequate choices within a very short period of time. The decisions made during the design phase have a major impact on the final structure and on its production cost. We propose new algorithms to compute near-optimal solutions of the discrete structural optimization problem. In the second part of the thesis, we turn to the building process of large ships and we present new methods to improve production facility management of shipyards. The ship building process requires the production and the assembly of tens, or even hundreds of thousands of steel elements. We define a space and time allocation problem that arises in assembly halls producing large building blocks and we develop algorithms for its solution. A successful implementation of a flexible and robust application is nowadays in use at a shipyard. [less ▲]

Detailed reference viewed: 55 (7 ULg)
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See detailOptimization model for empty container repositioning
Salmon, Frédéric ULg; Limbourg, Sabine ULg

Conference (2013, February 07)

Empty container management is a transportation issue relating to the imbalance of container demand and supply in various parts of the world. Hence the necessity for shippers to move empty containers to ... [more ▼]

Empty container management is a transportation issue relating to the imbalance of container demand and supply in various parts of the world. Hence the necessity for shippers to move empty containers to supply areas. The purpose of this research is to develop a decision support tool applying to intermodal freight transport. This project aims at minimizing the overall cost of empty container management in the hinterlands of the ports of Antwerp and Rotterdam. The proposed model is a two-stage stochastic network model which takes account of transit time between ports and terminals, shipping cost, the carrying capacity of the various modes of transport, the stochastic demand and supply of each terminal and port as well as other parameters such as substitution or holding costs. In addition, the proposed model considers the possibility of intermodality with road transportation. Along with the optimal solution, our experimental data should yield an understanding of the impact of costs on the repartition of ows and inventories [less ▲]

Detailed reference viewed: 19 (0 ULg)
See detailOptimization model for empty container repositioning
Salmon, Frédéric ULg; Limbourg, Sabine ULg

Scientific conference (2013, February 07)

Empty container management is a transportation issue relating to the imbalance of container demand and supply. This project aims at minimizing the overall cost of empty container management. It takes ... [more ▼]

Empty container management is a transportation issue relating to the imbalance of container demand and supply. This project aims at minimizing the overall cost of empty container management. It takes account of transit time, shipping cost, the carrying capacity of the various modes of transport, the stochastic demand and supply of each terminal and port as well as other parameters such as substitution or holding costs, plus the intermodality with road transportation. [less ▲]

Detailed reference viewed: 38 (5 ULg)
Peer Reviewed
See detailOptimization of a drug-cyclodextrin complexation reaction by a static supercritical carbon dioxide process
Brion, Michael; Nizet, Dominique; Evrard, Brigitte ULg

Poster (2008)

Detailed reference viewed: 10 (0 ULg)
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See detailOptimization of a formic/acetic acid delignification treatment on beech wood and its influence on the structural characteristics of the extracted lignins
Simon, Mathilde; Brostaux, Yves ULg; Vanderghem, Caroline ULg et al

in Journal of Chemical Technology & Biotechnology (2014), 89(1), 128-136

Background In order to replace petrochemicals by bio-based lignin products in a lot of high value-added applications, a formic/acetic acid treatment was adapted to beech wood (Fagus sylvatica L.) for ... [more ▼]

Background In order to replace petrochemicals by bio-based lignin products in a lot of high value-added applications, a formic/acetic acid treatment was adapted to beech wood (Fagus sylvatica L.) for lignin extraction. Results Beech wood particles were delignified at atmospheric pressure by a formic acid/acetic acid/water mixture. Cooking time and temperature were optimized for delignification, pulp yield and 2-furfural concentration. Response surface design analysis revealed that delignification yield increased with cooking time and temperature. Conclusion The multi-criteria optimization of delignification was used to find the ideal cooking conditions (5h07 min, 104.2°C) which could be satisfactory for the maximization of delignification (70.5%) and pulp yield (58.7%) and, to a lesser extent, for the minimization of 2-furfural production. Treatment conditions were found to influence the chemical structure of extracted lignins. Cooking time and temperature influenced inversely lignin molecular weights. [less ▲]

Detailed reference viewed: 49 (30 ULg)
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See detailOptimization of a formic/acetic acid treatment of beech wood (Fagus sylvatica L.) for delignification
Simon, Mathilde ULg; Richel, Aurore ULg; Vanderghem, Caroline ULg et al

Poster (2011)

Lignin is a promising molecule constituting a renewable alternative to some petrochemical industry products. Lignin is an aromatic cross-linked heteropolymer composed of three phenylpropanoids (p ... [more ▼]

Lignin is a promising molecule constituting a renewable alternative to some petrochemical industry products. Lignin is an aromatic cross-linked heteropolymer composed of three phenylpropanoids (p-hydroxyphenyl, guaiacyl and syringyl units) linked together via radical coupling reactions by specific ether or carbon-carbon bonds. With this phenylpropanoid structure, lignin is a rich resource of biobased products that could find high-valued applications in a lot of different areas like petrochemical polymer reinforcement and replacement, antioxidants, stabilizers, resins and vanillin production... The first challenge of the valorization of lignins is their extraction from raw materials. Lignins can be found in different lignocellulosic substrates like grasses, softwood and hardwood. This extraction process needs the development of suitable biomass treatments, allowing efficient lignin recuperation without degradation. This one could lead to the loss of some interesting properties and so of some valorization possibilities. In this study, beech wood (Fagus sylvatica L.) was collected in the region of Gaume (Belgium). Beech wood particles were delignified at atmospheric pressure by a mixture of formic acid/acetic acid/water. A central composite design and response surface methodology were used for the optimization of treatment parameters for delignification. The optima of two independent variables, namely time (1h30, 3h, 4h30) and temperature (87°C, 97°C, 107°C), were determined on delignification yield, pulp yield, concentration of degradation products (furfural and hydroxymethylfurfural). Moreover, the impact of these two variables on the amount of residual linkages between phenylpropanoid units was evaluated by semi-quantitative bidimensional nuclear magnetic resonance spectroscopy (NMR-HSQC). Our results highlight that the delignification yields increase when cooking time and temperature are elevated. Nevertheless, under these conditions, pulp yield decreases as hydrolysis of hemicelluloses and cellulose occurs. The hydrolysates of carbohydrates (free sugars or oligosaccharides) are contained in the black liquor. At elevated temperature and time, the amount of degradation products in the black liquor is increased. [less ▲]

Detailed reference viewed: 48 (9 ULg)
See detailOptimization of a formic/acetic acid treatment of beech wood for lignin extraction
Simon, Mathilde ULg; Richel, Aurore ULg; Vanderghem, Caroline ULg et al

Conference (2012, August)

Lignocellulosic substrates are a promising alternative resource for the sustainable production of energy (biofuels), bio-based products and organic compounds. In the past, the extraction and recycling of ... [more ▼]

Lignocellulosic substrates are a promising alternative resource for the sustainable production of energy (biofuels), bio-based products and organic compounds. In the past, the extraction and recycling of cellulose (into fermentable glucose) constituted the central axis of lignocellulosic biorefinery processes. Degraded hemicelluloses and lignins were recovered as side-products with no possibilities of high-added value applications. Within the context of an integrated biorefinery, and for economic reasons, the recovery and the non-energetic valorization of lignins have opened recently new horizons. Lignin is a cross-linked phenolic polymer and is considered as potential alternative to petrochemical polymers or as a source of antioxidants for cosmetics and food industry, resins, chelating agent... As the final application of lignin depends on both extraction process and type of lignocellulosic sources, the development of fast and efficient physicochemical characterization methods is thus a prerequisite to optimize extraction processing conditions. In this study, beech wood particles (Fagus sylvatica L.) are delignified at atmospheric pressure by a formic acid/acetic acid/water mixture. Firstly, response surface methodology is used to optimize cooking time and temperature for delignification, pulp yield and concentration of degradation products (2-furfural and 5-hydroxymethylfurfural). The results highlight that best delignification is obtained in the highest cooking times and temperatures and that 5-hydroxymethylfurfural is produced during the formic/acetic acid treatment but is also degraded into 2-furfural. With the aim to develop an integrated biorefinery approach, multi-criteria optimization is used to find ideal cooking time and temperature (5h07, 104.2°C) leading to the maximization of delignification and pulp yield and to the minimization of 2-furfural production Finally, physicochemical and chemical structures of extracted lignins are found dependent on treatment conditions harshness. [less ▲]

Detailed reference viewed: 78 (23 ULg)
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See detailOptimization Of A Heat Pump For Satellite Cooling
Bell, Ian ULg; Lemort, Vincent

in 15 th International Refrigeration and Air Conditioning Conference at Purdue (2014, July)

Detailed reference viewed: 16 (3 ULg)
Peer Reviewed
See detailOptimization of a high performance thin layer chromatography method to quantify solanines in patatoes
Bodart, P.; Hubert, Philippe ULg; Angenot, Luc ULg et al

in Journal de Pharmacie de Belgique (1999), 54

Detailed reference viewed: 17 (0 ULg)