Browsing
     by title


0-9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

or enter first few letters:   
OK
Full Text
Peer Reviewed
See detailAn Optimistic Posterior Sampling Strategy for Bayesian Reinforcement Learning
Fonteneau, Raphaël ULg; Korda, Nathan; Munos, Rémi

in NIPS 2013 Workshop on Bayesian Optimization (BayesOpt2013) (2013)

We consider the problem of decision making in the context of unknown Markov decision processes with finite state and action spaces. In a Bayesian reinforcement learning framework, we propose an optimistic ... [more ▼]

We consider the problem of decision making in the context of unknown Markov decision processes with finite state and action spaces. In a Bayesian reinforcement learning framework, we propose an optimistic posterior sampling strategy based on the maximization of state-action value functions of MDPs sampled from the posterior. First experiments are promising. [less ▲]

Detailed reference viewed: 65 (0 ULg)
Full Text
See detailOPTIMIZACIÓN DE BIOMATERIALES PARA MODIFICACIÓN DE LA SUPERFICIE CELULAR
Cerda-Cristerna, B.I.; Flores, H; Pozos, A et al

Poster (2010, December)

Detailed reference viewed: 14 (0 ULg)
Full Text
Peer Reviewed
See detailOptimization and analysis of lock gates in the framework of the "Seine-Escaut Est" waterway upgrading
Gernay, Thomas ULg

in Bulletin of the Permanent International Association of Navigation Congresses (2010), (141), 11-26

This paper presents a research study performed on lock gates. It concerns the downstream lock gate of the one of the four new locks planned within the framework of the “Seine-Escaut Est (SEE)” project in ... [more ▼]

This paper presents a research study performed on lock gates. It concerns the downstream lock gate of the one of the four new locks planned within the framework of the “Seine-Escaut Est (SEE)” project in the Walloon Region of Belgium. At the stage of the basic preliminary design, it was decided to use four identical gates, all suspended and moved transversally to the lock. On this basis, the present work tackles different aspects of the lock gate study. The aim is double: on the one hand, to advance in the study of the four SEE project downstream lock gates, and on the other hand, to focus more particularly on lock gate structural analysis, notably the design, optimization and structural behavior in the case of ship impact. First, the design and optimization of the gate are performed, using the LBR5 lock gate optimization software and a linear elastic analysis. An optimized solution is obtained considering the best compromise between the cost and weight aspects of the structure. Then, this optimized gate is modeled with the nonlinear finite elements software FINELG. This program is used to conduct non linear numerical analysis of the effect of boat impact on the previously optimized downstream gate. Several analyses are performed, which allow for a discussion on the influence of the stiffener dimensions and the impact zone on the structural behavior of the gate submitted to the impact. Two different behaviors are brought to light, a ductile one and a fragile one. The results of the numerical analysis underline the importance of the development of a global plastic mechanism with the purpose of dissipating a large amount of energy. Finally, an analytical model presented in literature allows for the simplified calculation of the gate theoretical strength in case of ship impact, and the calculated value is compared with the computed results. [less ▲]

Detailed reference viewed: 70 (34 ULg)
Full Text
Peer Reviewed
See detailOptimization and Application of Electrophoretic Mobility Analysis of Human Red Blood Cells to Study Their in Vitro Stability, Interaction with Polycations and Proteolytic Enzymes
Grandfils, Christian ULg; Foresto, P.; Riquelme, B. et al

in Journal of Biomedical Materials Research, Part A (2008), 84(2), 535-44

Electrophoretic light scattering method has been considered to determine both the mean and polydispersity of electrophoretic mobility of normal human red blood cells. The final goal of our study was to ... [more ▼]

Electrophoretic light scattering method has been considered to determine both the mean and polydispersity of electrophoretic mobility of normal human red blood cells. The final goal of our study was to optimize an in vitro test allowing us to investigate the interaction of xenobiotics, in particular polyelectrolytes, with blood cells. The feasibility of our method has been evaluated based on the reproducibility of our technique to analyze the native electrophoretic mobility of human RBCs, as well as their evolution in the presence of polycationic compounds, i.e. a natural polyamine, spermine, and a synthetic polycation, a polyethylenimine (PEI). Additionally, the follow-up of the human RBCs electrophoretic mobility has been controlled after their incubation with neuraminidase. [less ▲]

Detailed reference viewed: 4 (0 ULg)
Full Text
Peer Reviewed
See detailOptimization and validation of arsenic determination in foods by hydride generation flame atomic absorption spectrometry
Kabengera, C.; Bodart, P.; Hubert, Philippe ULg et al

in Journal of AOAC International (2002), 85(1, Jan-Feb), 122-127

A hydride generation flame atomic absorption spectrometric method was developed and optimized to quantitate arsenic (As) in foods. A wet digestion of the samples with HNO3 + H2O2 was performed and excess ... [more ▼]

A hydride generation flame atomic absorption spectrometric method was developed and optimized to quantitate arsenic (As) in foods. A wet digestion of the samples with HNO3 + H2O2 was performed and excess oxidants were eliminated by addition of hydrochloric acid and urea. As5+ in As3+ was then reduced by potassium iodide. The As3+ solution was analyzed by generation of arsine with sodium tetrahydroborate. As determination ranged from 2.5 to 20 microg/L, with a determination coefficient of 0.997. The limits of detection (LOD) and quantitation (LOQ) were 0.6 and 2.1 microg/L, respectively. The method was validated and good results were obtained for recovery, precision, accuracy, LOD, and LOQ. This method is now used to analyze foods from Rwanda. [less ▲]

Detailed reference viewed: 30 (2 ULg)
Full Text
Peer Reviewed
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: 14 (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)
Full Text
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: 37 (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: 6 (1 ULg)
Full Text
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: 58 (7 ULg)
Full Text
Peer Reviewed
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: 24 (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)