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Degenerate Anisotropic Elliptic Problems and Magnetized Plasma Simulations

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Communications in Computational Physics 2012年第1期11卷 147-178页

作者： stephane Brull Pierre Degond Fabrice Deluzet Institut de Mathematiques de Bordeaux UMR 5251 Equipe Mathematiques Appliquees de Bordeaux(MAB)Universite Bordeaux 1351cours de la Liberation-33405 TALENCE cedexFrance Universite de Toulouse UPSINSAUT1UTMInstitut de Mathematiques de ToulouseF-31062 ToulouseFrance CNRS Institut de Mathematiques de Toulouse UMR 5219F-31062 ToulouseFrance

This paper is devoted to the numerical approximation of a degenerate anisotropic elliptic *** numerical method is designed for arbitrary spacedependent anisotropy directions and does not require any specially adapted coordinate *** is also designed to be equally accurate in the strongly and the mildly anisotropic *** method is applied to the Euler-Lorentz system,in the drift-fluid *** system provides a model for magnetized plasmas.

关键词： Anisotropic elliptic problem asymptotic-preserving scheme Lorentz force large magnetic field low-Mach number drift-fluid limit

A Maximum Likelihood TOA Based Estimator For Localization in Heterogeneous Networks

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International Journal of Communications, Network and System Sciences 2010年第1期3卷 38-42页

作者： Mohamed LAARAIEDH stephane AVRILLON Bernard UGUEN 不详

In this paper, we exploit the concept of data fusion in hybrid localization systems by combining different TOA (Time of Arrival) observables coming from different RATs (Radio Access Technology) and characterized by different precisions in order to enhance the positioning accuracy. A new Maximum Likelihood estimator is developed to fuse different measured ranges with different variances. In order to evaluate this estimator, Monte Carlo simulations are carried out in a generic environment and Cramer Rao Lower Bounds (CRLB) are investigated. This algorithm shows enhanced positioning accuracy at reasonable noise levels comparing to the typical Weighted Least Square estimator. The CRLB reveals that the choice of the number, and the configuration of Anchor nodes, and the type of RAT may enhance positioning accuracy.

关键词： Localization TOA Ranging Weighted least square Maximum Likelihood Hybrid Data Fusion UWB WLAN Cramer Rao Lower Bound

Designing an Automatic Control System for the Improved Functioning of a Solar Wall with Phase Change Material (PCM)

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Open Journal of Energy Efficiency 2016年第1期5卷 19-29页

作者： Patrick Favier Laurent Zalewski stephane Lassue Sohail Anwar IUT Bethune Université d’ Artois Arras France LGCgE Laboratory Université d’ Artois Arras France Department of Engineering Altoona College Pennsylvania State University Altoona PA USA

Solar walls constitute an important green architectural feature that positively contributes to energy saving in buildings. Different configurations may be proposed, such as, solar wall with Phase Change Material (PCM), composite solar wall, photovoltaic solar wall, zigzag solar wall, and solar hybrid wall. Being environmentally friendly, these passive solar components can provide thermal comfort and help save energy. Their disadvantages include principally unpredictable heat transfer, heat losses by night for some systems or inverse thermo-siphon phenomenon. Appropriate energy management techniques can be used to control and optimize the performances of solar walls. An experimental study for energy management of a PCM based solar wall is described in this paper. The experimental results show the effectiveness of the proposed automatic control system in regulating the capture of solar energy.

关键词： Solar Walls Solar Energy Energy Storage Phase Change Material Energy Management

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工业供应链中供应商的选择模型研究

工业供应链中供应商的选择模型研究

作者： Yossanguem Madjinoudji stephane 重庆大学

学位级别：硕士

对于想在本领域有竞争性的公司而言,选择供应商的问题是决策过程中至关重要组成部分。供应商的选择是一个费时费力的工作,涉及到采集数据和仔细分析影响决策好坏的各种因素。然而对于每个公司而言,供应商的选择是一个影响显著的关键的... 详细信息

对于想在本领域有竞争性的公司而言,选择供应商的问题是决策过程中至关重要组成部分。供应商的选择是一个费时费力的工作,涉及到采集数据和仔细分析影响决策好坏的各种因素。然而对于每个公司而言,供应商的选择是一个影响显著的关键的环节。本文中,明确了选择供应商过程中的八大评价标准,即:科技含量、柔性化、产品质量、公司财力、配送速度、亲近程度、组织文化和策略、产品价格。对这些标准进行细分,又可分为22项子标准。明确这些标准后,通过问卷调查及走访一些公司来确定在实际选择合作伙伴的过程中哪一项因素所占比重较大。通过数据处理及结果解读,采用线性加权模型来表示每个因素的重要性。该模型属于分层结构,可应用目标函数方法进行分析计算。运用人工神经网络(ANN)重新计算标准比重来提高目标函数准确性,以便帮助公司做出正确的选择。本文的目的是帮助买方/公司建立一个评估和选择的参考模型,该模型可以在选择供应链过程中为买方/公司指引方向或提供一种新的模式。

关键词：供应商选择评估准则权重人工神经网络

Preliminary Study of Simulated HLW Glass Alteration in Aqueous With Simple Fracture

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Preliminary Study of Simulated HLW Glass Alteration in Aqueo...

Advanced Technology to Anneal Current and Future AHSS

作者： ZHANG Hua GIN stephane CEA-Marcoule France

The nuclear glass block is fractured after it is poured into the *** alteration of glass involves essentially surface mechanisms;hence it is great importance to determine the surface area of the fractured glass block subject to alteration in order to compute the quantities of altered glass and the radio nuclides liable to be released from the glass depending on the environmental *** lab experiments have been done to study the solution transport and chemistry mechanism. In this experiment,a simple fracture was developed to study the effect of fracture on simulated HLW glass *** composition of the sample is same as R7T7 type glass,and the solution analysis

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Advanced Technology to Anneal Current and Future AHSS

Disparities in Agricultural Practices According to Cashew Nut Production Regions in Côte d’Ivoire and Probable Incidence on Nut Quality

“第十届中国钢铁年会”暨“第六届宝钢学术年会”

作者： Eric Magadoux stephane Mehrain

Water Quench technology has been used on certain continuous annealing lines for more than 30 years now to produce HSS grades and the market tendency for higher strength steel grades is accelerating today. Various AHSS grades have been developed for which yield strength and other properties are also considered, to ensure formability. The production of AHSS grades in a continuous annealing line requires a strict cooling control to limit strength deviation within the coil to improve homogeneity and formability. To reach the required AHSS characteristics, Wet Flash Cooling;has been developed, offering a more flexible control of the strip cooling cycle, including initial and final strip temperatures and modulation of cooling rate. This technology has been successfully operating in a large capacity industrial continuous annealing line at a major steel plant for 6 years following its start up in 2009. This paper describes the new challenges of quenching technologies to respond to the evolving AHSS production needs.

关键词： water cooling cooling flexibility martensite Q&P

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Agricultural Sciences 2021年第10期12卷 1168-1183页

作者： Koffi Yao stephane Kouadio James Halbin Soya Joseph Research Group of Crop Production Quality Management Laboratory of Agrovalorisation UFR Agroforesterie Jean Lorougnon Guédé University Daloa C&#244 te d’Ivoire Laboratory of (Bio) Toxicology and Industrial Hygiene DPPSST CNPS Abidjan Abidjan C&#244 te d’Ivoire

Improving the quality of agricultural products depends largely on production process. In the absence of data on farmers’ practices and the average quality of cashew nuts in Côte d’Ivoire, the present study aimed to provide a detailed description of the cashew nut production process. Thus, a survey was carried out in the zones of Mankono, Dabakala and Bondoukou among 386 cashew producers selected at random and interviewed using the face-to-face technique. The results revealed that intercropping was practiced in cashew cultivation (42% - 62% of the producers), modern cultivation technique (72% - 98% of the producers) but with rare use of selected seeds (8% - 20% of the producers), labour/ha during nut harvesting (2.6 - 12 workers/ha). Concerning the harvesting process, the time taken to pick the nuts varies from 1 to 14 days;the use of pesticides during harvesting (14% to 97% of the producers) and the absence of sorting of the nuts in 42% of the Mankono producers justify the probable conservation of defective and immature nuts in their production. For drying, the main dryers were the slatted table, the cemented surface and the tarpaulin, but other dryers were found such as the mosquito net, the propylene rice bag, the fertiliser bag and the black bag. Generally, the drying time of cashew nuts was very short: 2 days (43% - 77% of the producers interviewed) but surprisingly 1 day (7% - 27% of the producers interviewed). For Mankono, the use of chemicals was permanent during all stages of the cashew production process. Overall, the results suggest the need to assess the real impact of farmers’ practices on the quality of cashew nuts from Côte d’Ivoire.

关键词： Cashew-Nuts Production-Process Quality-of-Nuts Pesticides

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弗朗西斯.福特.科波拉

Visualizing the importance of oxide-metal phase transitions in the production of synthesis gas over Ni catalysts

2020年

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Journal of Energy Chemistry 2020年第11期29卷 178-186页

作者： Luis Sandoval-Diaz Milivoj Plodinec Danail Ivanov stephane Poitel Adnan Hammud Hannah C.Nerl Robert Schldgl Thomas Lunkenbein Department of Inorganic Chemistry Fritz-Haber-Institut der Max-Planck-GesellschaftFaradayweg 4-614195 BerlinGermany Electron Spectrometry and Microscopy Laboratory School of Basic SciencesEcole Polytechnique Federale de Lausanne1015 LausanneSwitzerland Max Planck Institute for Chemical Energy Conversion StiftstraJSe 34-3645470 Miihlheim a.d.RuhrGermany

Synthesis gas, composed of H2 and CO, is an important fuel which serves as feedstock for industrially relevant processes, such as methanol or ammonia synthesis. The efficiency of these reactions depends on the H2: CO ratio, which can be controlled by a careful choice of reactants and catalyst surface ***, using a combination of environmental scanning electron microscopy(ESEM) and online mass spectrometry, direct visualization of the surface chemistry of a Ni catalyst during the production of synthesis gas was achieved for the first time. The insertion of a homebuilt quartz tube reactor in the modified ESEM chamber was key to success of the setup. The nature of chemical dynamics was revealed in the form of reversible oxide-metal phase transitions and surface transformations which occurred on the performing catalyst. The oxide-metal phase transitions were found to control the production of synthesis gas in the temperature regime between 700 and 900 ℃ in an atmosphere relevant for dry reforming of methane(DRM, CO2: CH4=0.75). This was confirmed using high resolution transmission electron microscopy imaging, electron energy loss spectroscopy, thermal analysis, and C18O2 labelled *** dedicated operando approach of simultaneously studying the surface processes of a catalyst and its activity allowed to uncover how phase transitions can steer catalytic reactions.

关键词： Dry reforming of methane Partial oxidation of methane Environmental scanning electron microscopy Synthesis gas Operando