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AN IMPROVED BRANCH-AND-BOUND ALGORITHM TO MINIMIZE THE WEIGHTED FLOWTIME ON IDENTICAL PARALLEL MACHINES WITH FAMILY SETUP TIMES

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Journal of Systems Science and Systems Engineering 2008年第4期17卷 446-459页

作者： Belgacem BETTAYEB Imed KACEM Kondo H.ADJALLAH LOSI-ICD cnrs fre 2848 Université de technologie de Troyes France

This article investigates identical parallel machines scheduling with family setup times. The objective function being the weighted sum of completion times, the problem is known to be strongly NP-hard. We propose a constructive heuristic algorithm and three complementary lower bounds. Two of these bounds proceed by elimination of setup times or by distributing each of them to jobs of the corresponding family, while the third one is based on a lagrangian relaxation. The bounds and the heuristic are incorporated into a branch-and-bound algorithm. Experimental results obtained outperform those of the methods presented in previous works, in term of size of solved problems.

关键词： Scheduling heuristic lower bound branch-and-bound algorithm identical parallel machines family setup times

Numerical Study of Heat Transfer and Contaminant Transport in an Unsaturated Porous Soil

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Journal of Water Resource and Protection 2014年第13期6卷 1238-1247页

作者： Abdelhamid Belghit Mustapha Benyaich Laboratory of Engineering Science for Environment—lasie fre-cnrs 3474 University of La Rochelle La Rochelle France Department of Physics Faculty of Science University Cadi Ayyad Marrakesh Morocco

Penetration of chemicals in the soil ground through irrigation water or rainfall induces important risks for the environment. These risks are badly known and may lead to direct contamination of the environment (atmosphere or ground water) or harmful effects on organisms living at ground level, indirectly affecting men. It is thus necessary to estimate these potential chemical risks on the environment. For that reason, the gradual change of these products (fertilizers, solutions, pollutants, ...) in the ground has been the subject of a lot of recent research works, based in particular on the study of non-saturated porous media in a theoretical, numerical or experimental way. Most of these works are incomplete and, in order to simplify the problem, they don’t take into accounts some process, which may be of prime importance under particular natural conditions. Complexity of such studies results from their multidisciplinary nature. In this communication, we study simultaneous transport of pollutant, the water that provides transport and the heat transfer in a 200 cm long cylindrical column full of sand taken as a non-saturated porous medium. We consider two kinds of conditions on the temperature at the column surface: the case of constant temperature and the case of sinusoidal temperature. We evaluate the influence of this temperature on the transfers. This study is purely numerical. We use the control volume method to determine hydrous, thermal and pollutant concentration profiles.

关键词： Soil Heat and Mass Transfer Porous Media Contaminant

ON IMPROVING AN INTEGRATED INVENTORY MODEL FOR A SINGLE VENDOR AND MULTIPLE BUYERS WITH A RELAXED MATERIAL ORDERING CYCLE POLICY

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Journal of Systems Science and Systems Engineering 2006年第3期15卷 298-313页

作者： Yugang YU Feng CHU Haoxun CHEN fre cnrs 2732 ISTIT-OSI University of Technology of Troyes 10010 Troyes France

In this paper, we propose a new model for improving the lot size obtained with the model of Woo, Hsu, and Wu （2001） proposed in their paper ＂An integrated inventory model for a single vendor and multiple buyers with ordering cost reduction＂（Int. J. Production Economics 73 203-215）. The new model can provide a lower or equal joint total cost as compared to Woo, Hsu, and Wu＇s model due to the relaxation of their integral multiple material ordering cycle policy to a fractional-integral multiple material ordering cycle policy. The proposed model is analyzed and an algorithm for calculating the optimal lot size of the model is developed. A numerical study based on the example used by Woo, Hsu, and Wu is presented.

关键词： Inventory integrated model raw materials single vendor multiple buyers

Numerical Methodology for Metal Forming Processes Using Elastoplastic Model with Damage Occurrence

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Journal of Materials Science & Technology 2006年第2期22卷 279-283页

作者： A.Cherouat H.Borouchaki K.Saanouni P.Laug LASMIS-cnrs fre 2719 University of Technology of Troyes BP 2060-10010TroyesFrance LASMIS-cnrs fre 2719 University of Technology of Troyes BP 2060-10010Troyes France LASMIS-cnrs fre 2719 University of Technology of Troyes BP 2060-10010 Troyes France INRIA Rocquencourt BP 105-78153 Le ChesnayFrance

Ductile damage often occurs during metal forming processes due to the large thermo-elasto （visco） plastic flow Iocalisation. This paper presents a numerical methodology, which aims to virtually improve any metal forming processes. The methodology is based on elastoplastic constitutive equations accounting for nonlinear mixed isotropic and kinematic hardening strongly coupled with isotropic ductile damage. An adaptive remeshing scheme based on geometrical and physical error estimates including a kill element procedure is used. Some numerical results are presented to show the capability of the model to predict the damage initiation and growth during the metal forming processes.

关键词： Finite elastoplasticity Ductile damage Error estimation Adaptive remeshing Metal forming processes

GUEST EDITORIAL:NEW TRENDS ON SERVICE SYSTEMS AND SERVICE MANAGEMENT

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Journal of Systems Science and Systems Engineering 2008年第2期17卷 129-131页

作者： Imed KACEM LOSI-ICD cnrs fre 2848 Université de technologie de TroyesFrance

The International Conference on Service Systems and Service Management （ICSSSM06） was held on October 25-27, 2006 in Troyes, France. This conference was sponsored by IEEE Systems, Man and Cybernetics Society. More than 500 articles were submitted to the conference and after a peer-reviewing process, 284 papers were accepted and published in the conference proceedings.

关键词： GUEST EDITORIAL FTL QN CLSP than

Needs of thermodynamic properties measurements and modeling in the frame of new regulations on refrigerants

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第5期8卷 724-733页

作者： COQUELET Christophe RICHON Dominique School of Mines of Paris CEP/TEPCNRS FRE 286135rue Saint HonoréFontainebleau 77305France

In 1987, the Montreal Protocol prohibited the worldwide use and production of chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) and hydro fluorocarbons (HFCs) were proposed as alternative refrigerants. Unfortunately, HFCs have non negligible global warning potential and therefore new refrigerants must be proposed or old refrigerants must be used associated with HFC. Accurate experimental thermodynamic data and predictive techniques are required for better under-standing of the performance of the newly proposed refrigerants. In this communication, experimental techniques based on either analytic or synthetic methods are first described. Data are reported. Then two newly developed predictive models based on thermodynamic approach with the isofugacity criterion and artificial neural network method are presented. The results can provide better evaluation of refrigerants, especially with the aim of studying global warning effects.

关键词： Refrigerants Experimental apparatus Thermodynamic Modeling Vapor-liquid equilibria (VLE) Phase diagram Density

Pressureless sintering behavior and properties of Ag-SnO_2

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Rare Metals 2019年第1期38卷 35-41页

作者： Henri Desplats Elodie Brisson Philippe Rogeon Patrick Carré Alexandre Bonhomme Department of Materials Engineering IRDL FRE CNRS 3744University of South Brittany Schneider Electric-Electropole 31 rue Pierre Mendes France

In this study, the results of measurements on pressureless sintering behavior of Ag-SnO_2(88%wt Ag,12%wt SnO_2) pellets were reported. Dilatometric measurements, relative densities, hardness values, rupture transverse strength and electrical conductivities function of sintering temperatures were presented. A constant thermal expansion coefficient was determined, and a threshold temperature of densification(T_d) was exhibited. Sintering kinetics were reported for different temperatures. Hardness values were measured, and no increase in hardness is found under Td. Three-points bending tests were used to determine the transverse rupture strength whose evolution appears importantly well under Td. In the same manner, the increase in initial electrical conductivities begins well under Td. Under the threshold temperature, the relative increase in electrical conductivity is found to be independent of initial density of green compact pellets. This work highlights different evolutions in function of sintering temperature for the electrical conductivity and transverse rupture strength on the one hand, and for the densification and hardness on the other hand.

关键词： Ag-SnO2 Pressureless sintering Dilatometry Mechanical properties Electrical conductivity

Compressive behavior and energy absorption of metal porous polymer composite with interpenetrating network structure

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中国有色金属学会会刊：英文版 2006年第B02期16卷 439-443页

作者： LIU Yu GONG Xiao-lu Institut Charles Delaunay CNRS FRE 2848 LASMIS UTT 12 rue Marie Curie BP 2060 10010 Troyes France

Interpenetrating phase composites (IPCs) are a new class of composite materials with improved combinations of mechanical and physical properties. This study was performed on a new type of IPC called metal porous polymer composite (MPPC) with an interpenetrating network structure. Aluminum-polypropylene (AI-PE) and Aluminum-epoxy resin (Al-Ep) composites were produced by infiltrating the polymer in the aluminum foam. The composite microstructures were characterized using SEM observation. The compressive behavior and energy absorption characteristics of MPPC were investigated and compared with the aluminum foams. The compressive modulus of composite was compared with the VOIGT-REUSS bounds and HASHIN-SHTRIKMAN (H-S) bounds models. The experimental modulus of compressive tests falls well within the theoretical models.

关键词：金属多孔聚合物复合物互穿网络结构压缩行为能量吸收 MPPC复合物

Direct growth of ZnO nanowires on civil engineering materials:smart materials for supported photodegradation

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Microsystems & Nanoengineering 2019年第1期5卷 70-76页

作者： Marie Le Pivert Romain Poupart Martine Capochichi-Gnambodoe Nathan Martin Yamin Leprince-Wang UniversitéParis-Est ESYCOM(CNRS-FRE2028)UPEM5 Boulevard Descartes77420 Champs sur MarneFrance

Photocatalysis is one of the most promising processes for treating air and water *** civil engineering materials for environmental depollution by photocatalysis have already been synthesized by incorporating TiO_(2) or ZnO nanoparticles in *** method suffers from two flaws:first,most of the NPs are incorporated into the cement and useless for photocatalysis;second,rain and wind could spread the potentially carcinogenic nanoparticles from the cement surface into ***,we propose the efficient synthesis of nontoxic and biocompatible ZnO nanostructures solely onto the surface of commercially available concrete and tiling pavements by a low-cost and lowtemperature hydrothermal *** samples exhibited enhanced photocatalytic activity for degrading organic dyes in aqueous media,and dye molecules are commonly used in the pharmaceutical,food,and textile *** studies showed no loss of efficiency after four photocatalysis *** supported structures,which are easy to implement onto the varying surfaces of commercially available materials,are promising for integration into civil engineering surfaces for environmental depollution in our daily life.

关键词： nanowires nanoparticles cement