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数学学报(中文版) 1982年第1期 20-27页

作者： U.D'AmBROSIO,R.CHALeAT,D.mANGeRON,m.SHImBO Instituto laboratoire Polytechnic Institute of Jassy.Iasi.Socialist Republic of Romania.At present:Visiting professor to the ImeCC Universidade estadual de Campinas SP Brasil. Division of Information engineering.Hokkaido University Japan. de matemática estatistica e Ci(?)ncia da Computacāo da Universidade estadual de Campinas Sāo Paulo Brasil. de mécanique appliquée de l'Université de Besancon France.

This paper deals with the existence,uniqueness,approximate solutions and errorsvaluation theorems concerning a class of nonlinear selfcontrolled systems with heredi-tary and polywave or polyvibrating ***,a stability p... 详细信息

关键词： INTeGRAL eQUATIONS meTHOD IN STUDIeS CONCeRNING CeRTAIN NONLINeAR SeLFCONTROLLeD SYSTemS WITH HeReDITARY AND POLYWAVe OR POLYVIBRATING OPeRATORS

Performance Analysis of a Vertical Axis Tidal Turbine With Flexible Blades

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Journal of marine Science and Application 2017年第1期16卷 73-80页

作者： mohamed Taher Bouzaher Belhi Guerira mohamed Hadid laboratoire de Génie mécanique Université de Biskra Biskra 07000 Algeria Unit of Applied Research in Renewable energy BP 88 Garat Ettaam Ghardaia Algeria

In this study, a vertical axis tidal turbine with flexible blades is investigated. The focus is on analyzing the effect of flexible airfoils types and blade flexibility on turbine net output power. To this end, five different flexible airfoils （Symmetric and Non-symmetric） are employed. The results show that the use of a thick flexible symmetric airfoil can effectively increase output power compared to that achievable with a conventional rigid blade. moreover, the use of highly flexible blades, as opposed to less flexible or rigid blades, is not recommended.

关键词： flexible blades vertical axis tidal turbine energy harnessing efficiency flow control rigid blade performance analysis

The evolution of Pore Water pressure in a Saturated Soil Layer between Two Draining Zones by Analytical and Numerical methods

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Open Journal of Civil engineering 2015年第4期5卷 390-398页

作者： Abib Tall Cheikh mbow Daouda Sangar&eacute mapath&eacute Ndiaye Papa Sanou Faye laboratoire de m&eacute canique et mod&eacute lisation UFR Sciences de l’Ing&eacute nieur Univer-sit&eacute de Thi&egrave s Thi&egrave s S&eacute n&eacute gal Groupe de Recherches sur les dynamiques des Syst&egrave mes et la m&eacute canique des Fluides Fac-ult&eacute des Sciences et Techniques Universit&eacute Cheikh Anta Diop Dakar S&eacute n&eacute gal laboratoire d’Analyse Num&eacute rique et d’Informatique UFR Sciences Appliqu&eacute es et Technologie Universit&eacute

The building of the infrastructure on the compressible and saturated soils presents sometimes major difficulties. The infrastructure undergoes strong settlement that can be due to several phenomena of consolidation of the soils. The latter results from the dissipation of the excess pore pressure and deformation of the solid skeleton. Terzaghi theory led to the equation modeling the dissipation of excess pore pressure. The objective of this study is to establish solutions, by analytical and numerical method, of the equation of the pore water pressure. We considered a compressible saturated soil layer, between two drainage areas and subjected to a uniform load. Separation of variables is used to obtain an analytical solution and the finite element method for the numerical solution. The results obtained by the finite element method have validated those of analytical resolution.

关键词： Pore Water pressure primary Consolidation Saturated Soil Separated Variables Finite element

Influences of graphene nanoplatelet aspect ratio and thermal treatment on dielectric performances of poly(methyl methacrylate)composites

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High Voltage 2016年第4期1卷 146-150页

作者： Benhui Fan Yu Liu delong He Jinbo Bai laboratoire mécanique des Sols Structures et Matériaux(MSSMat)CNRS UMR 8579Ecole CentraleSupelecUniversitéParis SaclayGrande Voie des Vignes92290 Chatenay-MalabryFrance

The dielectric property and percolated behaviour of polymer matrix composites largely depend on the morphology of conductive fillers and external stimulations especially when the composites are processed by melting blending and extrusion-injection *** this study,the poly(methyl methacrylate)(PmmA)matrix composites incorporated by two kinds of graphene nanoplatelets(GNP),G5 and G150 with different aspect ratios(the ratio of diameter and thickness)are prepared to study the influence of GNP morphology on the dielectric performances close to percolation threshold(f_(c)).After annealing at glass transition temperature(T_(g))for 1 h,the dielectric permittivities of PmmA/G5 and PmmA/G150 near fc increase 43 and 38%,respectively,while the dielectric loss change *** improvement on the dielectric property is possibly attributed to the slight change of the distance between adjacent GNPs after annealing at T_(g)which enables to arouse stronger polarisation by tunnelling effect.

关键词： composites dielectric property

Resilient modulus of Compacted Lateritic Soils from Senegal at OPm Conditions

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Geomaterials 2013年第4期3卷 165-171页

作者： Fatou Samb meissa Fall Yves Berthaud makhaly Ba laboratoire d’ Alembert—Université Pierre et marie Curie Paris France laboratoire de mécanique et modélisation—UFR Sciences de l’ Ingénieur Université de Thiès Thiès Sénégal

Repeated load triaxial tests were performed on five compacted gravel lateritic soils collected from different locations in Senegal: Sébikotane, Dougar, Pa Lo, mont-Rolland and Ngoundiane. The study revealed that resilient modulus decreases with the increase of the bulk and deviatoric stress in constant confining pressure. In addition, resilient modulus increases with the percentage of cement for appreciably equal contents of moisture. This effect tends to stop for higher stress. Besides, correlations were made with some models of resilient modulus such as the Uzan-Witczack model (Witczack and Uzan, 1988 [1]) and the National Highway Research program (NCHRP) model (2004 [2]). The study confirms that both models give very good results with the best correlations being obtained with the Uzan-Witczack model.

关键词： Gravel Lateritic Soils Resilient modulus mechanical Behaviour Pavement Cyclic Triaxial Test mechanistic design

Hydrodynamic Anisotropy effects on Radiation-mixed Convection Interaction in a Vertical Porous Channel

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Applied mathematics 2016年第1期7卷 22-39页

作者： G&eacute rard degan Christian Akowanou Latif Fagbemi Joël Zinsalo laboratoire d’energ&eacute tique et de m&eacute canique appliqu&eacute es (LemA) Ecole Polytechnique d’Abomey-Calavi (EPAC) Universit&eacute d’Abomey-Calavi (UAC) Cotonou B&eacute nin department of mechanical engineering Ecole de Technologie Sup&eacute rieure Montr&eacute al Canada

The effects of hydrodynamic anisotropy on the mixed-convection in a vertical porous channel heated on its plates with a thermal radiation are investigated analytically for fully developed flow regime. The porous medium is anisotropic in permeability whose principal axes are oriented in a direction that is oblique to the gravity. The generalized Brinkman-extended Darcy model which allows the no-slip boundary-condition on solid wall is used in the formulation of the problem. The flow reversal, the thermal radiation influence for natural, and forced convection are considered in the limiting cases for low and high porosity media. It was found that the anisotropic permeability ratio, the orientation angle of the principal axes of permeability and the radiation parameter affected significantly the flow regime and the heat transfer.

关键词： mixed-Convection Thermal Radiation Anisotropic Porous medium Flow Reversal Heat Transfer

Hydric properties evolution of <i>Spirulina platensis</i>during Drying: experimental Analysis and modeling

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Food and Nutrition Sciences 2019年第6期10卷 561-577页

作者： eloi Salmwendé Tiendrebeogo Guy Christian Tubreoumya A. O. Dissa A. Compaoré Jean Koulidiati F. Cherblanc J.-C. Bénet I. Youm laboratoire de Physique et de Chimie de L’environnement (LPCe) Université Ouaga 1 Pr Joseph Ki-Zerbo Ouagadougou Burkina Faso laboratoire de mécanique et Génie Civil (LmGC) CNRS Université de Montpellier 2 Montpellier France Centre de Recherche sur les energies Renouvelables (CeReR) Université Cheick Anta Diop Dakar Sénégal

Hydric properties evolution during drying differs from one product to another and has been the subject of various studies due to its crucial importance in modeling the drying process. The variation of these parameters in the solid matrix and in time during the drying of Spirulina platensis has not known an advanced understanding. The objective of this study was to evaluate the evolution of the water content profile, the mass flow, the concentration gradient and the diffusion coefficient during the drying of Spirulina platensis taking into account the shrinkage. modeling and experimental analysis (at 50°C and HR = 6%) by the cutting method a cylinder 20 mm in diameter and 40 mm thick were carried. The water content profiles of two different products grown in semi-industrial farms from Burkina Faso and France with initial water contents respectively of the range from 2.73 kgw/kgdb and 3.12 kgw/kgdb were determined. These profiles have been adjusted by a polynomial function. Identical water behavior is observed regardless of the origin of the samples. Water distribution is heterogeneous. mass flow and concentration gradient are greater at the edge than inside the product. The water transport coefficient, ranging from 1.70 × 10?10 to 94 × 10?10 m2/s, is determined from a linear approach.

关键词： Drying experiment modeling Spirulina platensis Hydric property

FLOWABILITY INdeX OF STOReD BULK FOOD prODUCTS

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FLOWABILITY INDEX OF STORED BULK FOOD PRODUCTS

design and development of High efficiency 150 kW Very Compact PLA Core electromagnetic Coupler for Highly Resonant Power Transfer Technology

The Second International Conference on measurement and Control of Granular materials

作者： minh Phong LUONG CNRS 317 Laboratoire de Mécanique des Solides Ecole Polytechnique91128 PalaiseauFrance

Silo storage of bulk solid materials generates an unsual class of both structural and functional failure problems,resulting often from an incomplete understanding of the rheology of the stored products,A realistic knowledge of their mechanical behaviour should permit a better evaluation of loads and stresses on the silo *** paper proposes a rheological characterization of some granular food products on different stress paths using the conventional triaxial *** characteristic state concept or disaggregation threshold of the granular structure reveals to be quite suitable and even indispensible for examining the mechanical behaviour and the flowability of the stored bulk materials.

关键词： silo storage bulk materials characteristic threshold arching flowability index

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Journal of electromagnetic Analysis and Applications 2020年第9期12卷 131-144页

作者： Fatima Zahra Boudara marc Rivaletto Laurent Pecastaing Antoine Silvestre de Ferron Sylvain Paquet Jean-Pierre Brasile Univ Pau & Pays Adour/e2s Uppa Laboratoire Des Sciences De L’ingénieur Appliquées A La Mécanique Et Au Génie Electrique Federation Ipra Ea4581 Pau France effitech Pau France

Highly Resonant Power Transfer (HRPT) technology is currently receiving very significant attention from the industry and the smart power grid distribution community in particular. This technology ensures electrical power transmission between two points while controlling the level of transmitted power and ensures the immediate shutdown of the transmitted power in the event of a problem. This paper reviews the inductive power transfer method and describes the design of an ultra-compact PLA core electromagnetic coupler. The proposed architecture confines the magnetic field in a toroidal PLA core transformer, and by avoiding the use of heavy and bulky shielding plates, reduces magnetic losses and avoids the Curie point. As a result, the overall unit has a weight of 5 kg and a volume of only 0.013 m3. The electromagnetic coupler is capable of transferring a peak power of 150 kW with an operating frequency of 193 kHz, giving a satisfactory efficiency of 95%. The proposed novel system was first investigated through CST 3D numerical modelling to determine the electrical parameters of the coupler’s equivalent circuit and its efficiency, to verify its compatibility with the ICNIRP 2010 standard and to evaluate its temperature rise with an air-cooling system. Afterwards, the designed coupler was built with a 3D printing device and finally tested experimentally. Simulation and experimental results are compared and show a good agreement.

关键词： PLA Core Toroidal Coupler Resonant System Low Stray emission Smart Grid

Soil Subgrade’s Characterization and Classification of Thies (Senegal, West Africa) on a Radius of 2.5 Kilometers along Five Roads

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Geomaterials 2016年第1期6卷 1-17页

作者： e.H.B.m. Niakhate Séni Tamba makhaly Ba Adama Dione Issa Ndoye laboratoire de mécanique et modélisation-UFR Sciences de l’Ingénieur Université de Thies Thies Sénégal ecole Polytechnique de Thies (ePT/Thies) Thies Sénégal

This article explains the results of a study conducted on the characterizations of subgrade soils in the region of Thies. The road platforms are mainly composed of a background soil, which is generally overlapped by a surface layer that plays two roles. Firstly, it protects the soil structure, ensures the leveling, and facilitates the movement of vehicles. Secondly, it brings harmony in the mechanistic characteristics of the materials that compose the soil while improving the long-term life force. The methodology consisted in taking samples of subgrade soil along the roads all over the region of Thies in a 5 km diameter span. The identification tests allowed the Thies-Tivaoune, Thies-Khombole and Thies-Noto axes are characterized by tight sands, poorly graded size. While Thies Pout-axis is characteristic of severe solid particle size and spread well graded and serious to spread and well graded particle size. Finally the Thies-montrolland axis is characterized by severe to very tight particle size and graduated to spread and serious and well graded particle size. The specific gravity values found proctor test shows the presence of sand, sandy laterite and laterite. In the target area, polished soils of the A-3 type according to the AASHTO classification system are the most represented with 60%, followed by the A-2-6 type 25%, and the A-2-4 type with 9%, which are typical of gravel, clay, and silty sands. Soils of the A-1-b type (2%) typical of roc fragments, sands and clay are also represented. Polished sands of the A-3 type have a better efficiency on road infrastructures than other types of soil listed above. Finally, we’ve also noted the presence of soils of the A-2-7 and A-4 types with the low percentage of 2%. Subgrade soils of class S4 are the most represented with 58%, followed by those of class S5 with 42%. Samples of the Thies-montrolland road have a claylike plasticity (CL or CH group), while those of the Thies-Pout road belong to the mL or OL and CL or OL

关键词： Subgrade Soil mechanistic Pavement design Arc GIS AASHTO CBR Resilient modulus