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COURSE TIMETABLING AT A TUNISIAN UNIVERSITY:A CASE STUDY

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Journal of Systems Science and Systems Engineering 2008年第3期17卷 334-352页

作者： Abdelaziz DAMMAK Abdelkarim ELLOUMI Hichem KAMOUN jacques A.FERLAND Department of Applied Quantitative Methods GIAD Laboratory University of SfaxFSEGTunisia Department of Applied Quantitative Methods GlAD Laboratory University of SfaxFSEGTunisia Département d'Informatique et de Recherche Opérationnelle Universitéde Montréal QuébecCanada

This paper deals with the Course Timetabling Problem at an institution in a Tunisian University. We introduce a heuristic procedure to construct a feasible timetable for all lectures and tutorials taken by different groups of each sub-section of any section. We describe the timetabling problem using a list of all specific hard and soft constraints. We formulate the problem as a set of linear constraints using two sets of binary variables corresponding to lectures and tutorials, respectively. This heuristic is illustrated with real data for a sub-section of the Faculty of Economics and Management Sciences of Sfax in Tunisia, and the resulting timetables are compared with those generated manually. The results of another full section have confirmed the good quality of the proposed heuristic when compared with the hand made solution.

关键词： Educational timetabling integer programming implementations heuristic search

Chemical Indicator of Spinel During Partial Melting and Subsolidus Equilibration of Mantle Peridotite:Experimental Study and Application to Natural Rocks

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Acta Geologica Sinica(English Edition) 1995年第4期69卷 420-435页

作者： jacques Kornprobst Daniel Vielzeuf Departement de Geologie et Mineralogie University Blaise Pascal63038 Clermont-Ferrand FranceDepartement de Geologie et Mineralogie University Blaise Pascal63038 Clermont-Ferrand France

Systematic experimental studies on partial melting and subsolidus equilibration of three reconstituted spinel-peridotites have been carried out at temperatures ranging from 1000 to 1380℃ and pressures of 1.0 and 1.5 GPa. The results shows (1) during partial melting, Mg# [=Mg/(Mg+Fe)]and Cr# [=Cr/(Cr-Al)]of spinel increase with an increase in degrees of melting) (2) during subsolidus equilibration, with increasing temperatures, Mg# of spinel increases but Cr# of spinel remains almost unchanged in dunite and increases slightly in Iherzolite and harzburgite. The negative and quasi-linear Mg# -Cr# correlation of spinel represents an isotherm of total non-equilibrium. The same results have been obtained by means of mathematical modelling. It is also proved by Mg# -Cr# correlation of spinel in natural peridotites. As a result of the spinel subsolidus equilibration, only variation of Cr# of spinel is limited, and then Cr# of spinel can be used to estimate the relative degree of melting undergone by host rocks. The bigger Cr# of spinel is, the higher the degree of melting will be. By contrast, during crystallization magma, Mg# and Cr# of spinel decrease with decreasing temperatures. Likewise, Cr# of spinel in basalts may be used to indicate the feature of Cr2O3/Al2O3 of magma, and the compositional zoning of spinel may be used to study the evolution of magma (cooling rate and contamination).

关键词： peridotite spinel partial melfing subsolidus equilibration experimental study and application

Planning urban megaprojects in the Gulf： The international consultancy firms in urban planning between global and contingent

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Frontiers of Architectural Research 2016年第2期5卷 254-264页

作者： Oula Aoun jacques Teller ARGENCO Universite Liege Liege 4000 Belgium

Driven by globalization and market openings, many architecture and engineering firms have become global. By focusing on the urban megaprojects in the Gulf, a particular culturat and political context, this paper argues that such firms have a major role in the rapid urban transformation of Gulf countries and act as transfer agents of an international knowledge in the urban planning domain. However, the transfer is adapted by several context-related char- acteristics, such as local governance, urban knowledge, and regulatory framework. This paper explores the procedural adaptation of these firms to the Gulf Cooperation Council （GCC） in terms of internal structure, methodology, adopted tools, and interaction with the context. The level of learning that results from this transfer is also investigated.

关键词： Architecture andensineering firms Construction market GCC Urban megaprojects

PAPR Distribution Analysis at the Output of Nonlinear PAPR Reducers

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Journal of Signal and Information Processing 2012年第4期3卷 465-468页

作者： Désiré Guel jacques Palicot SUPELEC/IETR Campus de Rennes Avenue de la Boulaie CS 47601 F-35576 Cesson-Sévigné cedex

Nonlinear PAPR reducers, such as clipping and companding techniques, are some simple methods used to reduce the Peak-to-Average Power Ratio (PAPR). In this paper, assuming that the baseband OFDM signal is characterized as a band-limited complex Gaussian process, we investigate the PAPR distribution of an OFDM signal when it is passed through a nonlinear PAPR reducer. The obtained PAPR distribution depends on the nonlinear function which characterizes the PAPR reducer. Later in this paper, we apply the obtained PAPR distribution in the clipping case. The comparisons made between the proposed distribution and that obtained thanks to computer simulations show good agreement.

关键词： Orthogonal Frequency Division Multiplexing (OFDM) Peak-to-Average Power Ratio (PAPR) Distribution Nonlinear PAPR Reducers

Field investigation on friction factor in mountainous cobble-bed and boulder-bed rivers

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International Journal of Sediment Research 2011年第2期26卷 210-221页

作者： Hossein AFZALIMEHR jacques GALLICHAND Ehsan BAGHERI Department of Water Engineering Isfahan University of Technology Departement des sols et de genie agroalimentaire Universite Laval Water Engineering Department Isfahan University of Technology

This paper presents results of the friction factor of cobble-bed and boulder-bed rivers based on 23 field measurements in three mountainous rivers in *** reveal that features of our measured velocity profiles in boulder-bed rivers in mountainous region do not present a specific shape but illustrate specific pattern in cobble-bed *** difference is attributed to scale effect of relative submergence. It is found that the relative submergence in cobble and boulders-bed rivers is the only key parameter that influences friction factor estimation and other parameters such as particle Froude number and Froude number have few impacts on flow resistance of cobble-bed and boulder-bed *** proposed relationship for estimation for the friction factor should be useful for large coarse-bed rivers.

关键词： Boulder-bed Cobble-bed Friction factor Mountainous river Relative submergence

Investigation of turbulence characteristics in channel with dense vegetation

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International Journal of Sediment Research 2011年第3期26卷 269-280+282+281页

作者： Hossein AFZALIMEHR Razieh MOGHBEL jacques GALLICHAND Water Engineering Department Isfahan University of TechnologyIran 84156 Departement des sols et de genie agroalimentaire Universite LavalSt-FoyQcCanada

In this experimental study,the turbulent flow in a channel with vegetation by using sprouts of wheat on channel bed was *** different aspect ratios of channel were *** Acoustic Doppler Velocimetry was used to measure parameters of turbulent flow over submerged sprouts of wheat,such as velocity *** log law and the Reynolds shear stress distribution were applied. Results indicate that the position of the maximum turbulence intensity superposes on the inflection point situated over the top of submerged vegetation *** analysis shows that near the vegetation bed,the sweeps and ejections appear to be the most dominant phenomenon,while far from the vegetated bed,the outward is dominant *** also show that the aspect ratio plays an important role on the contribution of the different bursting events for Reynolds stress determination.

关键词： Bed vegetation Aspect ratio Reynolds stress Quadrant analysis

Modelling and mathematical results arising from ferromagnetic problems

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Science China Mathematics 2012年第5期55卷 1053-1067页

作者： DESCLOUX Jean FLUECK Michel RAPPAZ jacques Department of Mathematics Ecole Polytechnique Fdrale de Lausanne (EPFL)Lausanne 1015Switzerland

Abstract In this article, we investigate the equations of magnetostaties for a configuration where a ferromagnetic material occupies a bounded domain and is surrounded by vacuum. Furthermore, the ferromagnetic law takes the form B=μ0μr（｜H｜）Hi i.e., the magnetizing field H and the magnetic induction B are collinear, but the relative permeability μr is allowed to depend on the modulus of H. We prove the well-posedness of the magnetostatic problem under suitable convexity assumptions, and the convergence of several iterative methods, both for the original problem set in the Beppo-Levi space W1（R3）, and for a finite-dimensional approximation. The theoretical results are illustrated by numerical examples, which capture the known physical phenomena.

关键词： ferromagnetism nonlinear elliptic problems finite element methods optimisation algorithms

CO_2,carbonate-rich melts,and brines in the mantle

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Geoscience Frontiers 2014年第5期5卷 697-710页

作者： Maria-Luce Frezzotti jacques L.R.Touret Department of Earth and Environmental Sciences University Milano Bicocca.P.za Della Scienza 4.20126 Milano.Italy Mineralogy Universite Pierre et Marie Curie4 Place Jussieu 75272 Paris Cedex 05France

This paper reviews the origin and evolution of fluid inclusions in ultramaflc xenoliths, providing a framework for interpreting the chemistry of mantle fluids in the different geodynamic settings. Fluid inclusion data show that in the shallow mantle, at depths below about 100 km, the dominant fluid phase is CO2 ± brines, changing to alkali-, carbonate-rich （silicate） melts at higher pressures. Major solutes in aqueous fluids are chlorides, silica and alkalis （saline brines; 5-50 wt.% NaCl eq.）. Fluid inclusions in peridotites record CO2 fluxing from reacting metasomatic carbonate-rich melts at high pressures, and suggest significant upper-mantle carbon outgassing over time. Mantle-derived CO2 （±brines） may eventually reach upper-crustal levels, including the atmosphere, independently from, and additionally to magma degassing in active volcanoes.

关键词： Fluid inclusionPeridotiteMantle metasomatismCarbonate-rich meltCO2Saline brine

Heat Transfer Model with Two Heat Transfer Coefficients Along a M ultiperforated Plate-Application to Combustion Chamber Wall Cooling

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Journal of Thermal Science 2003年第4期12卷 363-366页

作者： Brice Petre Eva Dorignac Jean jacques Vullierme Laboratoire d'Etudes Thermiques U.M.R C.N.R.S 6608-ENSMA BP 40109 86961 Futuroscope Chasseneuil Cedex FRANCELaboratoire d'Etudes Thermiques U.M.R C.N.R.S 6608-ENSMA BP 40109 86961 Futuroscope Chasseneuil Cedex FRANCELaboratoire d'Etudes Thermiques U.M.R C.N.R.S 6608-ENSMA BP 40109 86961 Futuroscope Chasseneuil Cedex FRANCE

Walls' cooling of aeronautic propeller combustion chamber is performed with the injection, through the combustion chamber wall, of a part of the air coming from compressors placed upstream. Measurements of the wall thermal fields are made by infrared thermography along the injection wall. This injection wall is pierced by 9 rows of 8 holes (α=90°) in staggered configuration (p/D=s/D=6). We propose a model using two heat transfer coefficients to represent the convective exchanges. The results are non-dimensioned and presented in comparison with the case without holes. The use of this model allows us to define 4 zones. Those 4 zones exist for the 5 blowing rates.

关键词： multiperforation cooling heat transfer coefficients infrared thermography.