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线性化行为模型的迭代统计公差分析（英文）

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2015年第5期16卷 353-360页

作者： Antoine DUMAS Jean-Yves DANTAN Nicolas GAYTON Thomas BLES Robin LOEBL laboratoire conception fabrication commande Arts et Métiers Paris Tech MetzMETZ CEDEX 357078France Institut Pascal Clermont UniversitéIFMAUMR 6602BP 10448Clermont-Ferrand 63000France

目的:分析由制造过程产生的变化对机构行为造成的影响。主要分析线性化方法对失败率估计的影响,从而平衡模型线性化造成的误差、计算时间和结果准确性。创新点:简化优化步骤,将机构行为线性化为几个部分,取代整体蒙特卡洛法,并采用一种... 详细信息

目的:分析由制造过程产生的变化对机构行为造成的影响。主要分析线性化方法对失败率估计的影响,从而平衡模型线性化造成的误差、计算时间和结果准确性。创新点:简化优化步骤,将机构行为线性化为几个部分,取代整体蒙特卡洛法,并采用一种迭代算法得到更加精确的结果。方法:1.采用带有非线性约束条件的几何线性化方法和基于失败率置信区间的算法(图3、4和5);2.以一个器件连接器为例,验证该算法在估计装配失败率上的作用。结论:1.线性化方法不影响蒙特卡洛仿真时间;2.线性化次数对计算时间和失败率估计准确率有很大影响(表1);3.线性化迭代统计方法相对于蒙特卡洛法在计算时间、计算精度和计算效率上有很大的优越性。

关键词：公差分析失败率行为模型线性化蒙特卡洛线性化

Catalytic decomposition performance for O_3 and NO_2 in humid indoor air on a MnO_x/Al_2O_3 catalyst modified by a cost-effective chemical grafting method

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Journal of Environmental Sciences 2018年第12期30卷 58-70页

作者： Longwen Chen Michel Ondarts Jonathan Outin Yves Gonthier Evelyne Gonze Université Grenoble Alpes Université Savoie Mont Blanc CNRS Laboratoire d'Optimisation de la Conception et Ingénierie de l'Environnement(LOCIE)

Processes based on non-thermal plasma（NTP） for indoor air treatment inevitably lead to the formation of toxic by-products such as ozone（O3） and nitrogen oxides（NOx）. Adding a step of heterogeneous catalysis in series with NTP could allow for the decomposition of the by-products. Therefore, different catalysts were developed based on transition metal oxides, such as NiOx, CoOxand MnOxwith different weight percentage 1, 5 and 10 wt.%,deposited on a γ-Al2O3 support. The O3 removal efficiency（ORE） and the NOxremoval efficiency（NRE） were very encouraging in dry air： about 65% and 80%, respectively, by using2 g 5 wt.% MnOx/Al2O3 catalyst under the experimental conditions. However, strongly negative effects of relative humidity（RH） on the catalytic decomposition performance were observed. To overcome this limitation, the catalyst surface was modified to make it hydrophobic using a cost-effective chemical grafting method. This treatment consisted in impregnating the 5 wt.% MnOx/Al2O3 catalyst with different trichloro（alkyl）silanes（TCAS）.The effects of different linker lengths and amounts of TCAS for the hydrophobicity and the decomposition performance of surface-modified catalysts under humid conditions were investigated. Our results show that the surface-modified catalyst with the shortest linker and 0.25 mmol/gcatof modifying agent represents the best catalytic decomposition performance for O3. Its ORE is 41% at 60% RH, which is twice that of the non-modified catalyst.

关键词： Indoor air treatment Non-thermal plasma MnOx/Al2O3catalyst Surface modification Ozone

RSSI Based Localization of Bluetooth Devices for Visually Impaired

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Journal of Signal and Information Processing 2019年第2期10卷 37-57页

作者： Muhammad Irfan Aziz Thomas Owens Uzair Khaleeq-uz-Zaman Muhammad Bashir Akbar National University of Sciences and Technology Islamabad Pakistan Department of Electronic and Computer Engineering Brunel University West London UK laboratoire de conception fabrication commande Ecole Nationale Supérieure d’Arts et Métiers Metz France

Localization for visually impaired people in dynamically changing environments with unexpected hazards and obstacles is a current need. Many techniques have been discussed in the literature with respect to location-based services and techniques used for the positioning of devices. Time difference of arrival (TDOA), time of arrival (TOA) and received signal strength (RSS) have been widely used for the positioning but narrow band signals such as Bluetooth cannot efficiently utilize TDOA or TOA. Received signal strength indicator (RSSI) to measure RSS, has been found to be more reliable. RSSI measurement estimations depend heavily on the environmental interference. RSSI measurement estimations of Bluetooth systems can be improved either by improving the existing methodologies used to implement them or by using fusion techniques that employ Kalman filters to combine more than one RSSI method to improve the results significantly. This paper focuses on improving the existing methodology of measuring RSSI by proposing a new method using trilateration for localization of Bluetooth devices for visually impaired people. To validate the new method, class 2 Bluetooth devices (Blue Giga WT-12) were used with an evaluation board. The software required was developed in National Instruments LabView. The PCB was designed and manufactured as well. Experiments were then conducted, and surface plots of Bluetooth modules were obtained to show the signal interference and other environmental effects. Lastly, the results were discussed, and relevant conclusions were drawn.

关键词： Bluetooth Localization Navigation Assistance Received Signal Strength Indicator Visually Impaired

Transportation of low-grade thermal energy over long distance by ammonia-water absorption

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Chinese Science Bulletin 2009年第6期54卷 948-957页

作者： MA Qiang WANG RuZhu LUO LinGai XIA ZaiZhong LIN Peng Institute of Refrigeration and Cryogenics Shanghai Jiao Tong University Shanghai 200240 China laboratoire Optimisation de la conception et Ingenierie de I'Environnement Polytech'Savoie 73376 Le Bourget-Du-Lac France

This paper presents the importance and the cycle choice for long-distance transportation of low-grade thermal energy, and the thermodynamic and hydrodynamic feasibility of single-effect ammonia-water absorption system for heat or cold transportation over long distance are also involved. A model of a long-distance thermal energy transportation system is built and analyzed, which shows satisfactory and attractive results. When a steam heat source at 120℃ is available, the user site can get hot water output at about 55℃ with the thermal COP of about 0.6 and the electric COP of about 100 in winter, and cold water output at about 10℃ with the thermal COP of about 0.5 and the electric COP of 50 in summer. A small-size prototype is built to verify the performance analysis. Basically the experimental data show good accordance with the analysis results. The ammonia-water absorption system is a potential pro-spective solution for the heat or cold transportation over long distance.

关键词：氨水吸收式低品位热能远距离交通长途运输吸收系统流体力学运输系统

Suction variations and soil fabric of swelling compacted soils

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Journal of Rock Mechanics and Geotechnical Engineering 2010年第2期2卷 129-134页

作者： H.Nowamooz F.Masrouri laboratoire Environnement Géomécanique & OuvragesNancy Université laboratoire de Génie de la conception INSA de Strasbourg

This study addresses firstly the soil fabric variations of loose and dense compacted soil samples during a single wetting/drying cycle at suctions between 0 and 287.9 MPa using mainly the mercury intrusion porosimetry（MIP） *** suction techniques were employed to apply this wide suction range：the osmotic technique for suctions less than 8.5 MPa,and the vapor equilibrium or salt solution technique for suctions higher than 8.5 ***,the soil water retention curves（SWRCs） were predicted by the MIP test results for both loose and dense soil samples.A reasonable correspondence between MIP results and SWRCs was found on the wetting path at lower suctions close to saturation and on drying path at higher suctions.

关键词： expansive soil experimentation modelling drying/wetting cycle

A Lattice Boltzmann Model to Study Sedimentation Phenomena in Irrigation Canals

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Communications in Computational Physics 2013年第3期13卷 880-899页

作者： Olivier Marcou Bastien Chopard Samira El Yacoubi Boussad Hamroun Laurent Lefevre Eduardo Mendes Institut de Modelisation et Analyse en Geo-Environnement et Sante Universite de Perpignan Via DomitiaPerpignanFrance Computer Science Department University of GenevaSwitzerland laboratoire d’Automatique et de Genie des Procedes Universite Claude BernardLyonFrance laboratoire de conception et Integration des Systemes Grenoble INPValenceFrance

Fresh water is one of the most significant resources for human activities and survival,and irrigation is among the most important uses of *** sustainibility and performance of irrigation canals can be greatly affected by sediment transport and *** our previous works,we proposed a Lattice Boltzmann model for simulating a free surface flow in an irrigation canal,as an alternative to more traditional models mainly based on shallow water *** we introduce the sedimentation phenomenon into our model by adding a new algorithm,based on the earlier work by ***,*** and ***[9,11,12,27].Transport,erosion,deposition and toppling of sediments are taken into account and enable the global sedimentation algorithm to simulate different transport modes such as bed load and suspended *** the present work,we study both the behaviour of a sediment deposit located at an underflow submerged gate(depending on the gate opening and the flow discharge)and the influence of the presence of such a deposit on the *** numerical and experimental validations have been *** experiments were realized on the micro-canal of the LCIS laboratory at Valence,*** comparisons between simulations and experiments give good qualitative agreement.

关键词： Lattice Boltzmann method irrigation canals modeling sedimentation

MULTISCALE OPTIMIZATION OF FLOW DISTRIBUTION BY CONSTRUCTAL APPROACH

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China Particuology 2005年第6期3卷 329-336页

作者： Lingai Luo Daniel Tondeur laboratoire Optimisation de la conception et Ing#nierie de rEnvironnement ESlGEC-University de Savoie Campus Scientifique Savoie Technolac 73376 Le Bourget-Du-Lac cedex France laboratoire des Sciences du Genie Chimique CNRS-ENS/C 1 rue Grandvfl/e 54000 Nancy France

Constructal approach is a recent concept allowing to generate and optimize multi-scale structures, in particular, branching structures, connecting a microscopic world to a macroscopic one, from an engineer＇s point of view. Branching morphologies are found in many types of natural phenomena, and may be associated to some kind of optimization, expressing the evolutionary adaptation of natural systems to their environment, In a sense, the constructal approach tries to imitate this morphogenesis while short-cutting the trial-and-error of nature. The basic ideas underlying the constructal concept and methodology are illustrated here by the examples of fluid distribution to a multi-channel reactor, and of the design of a porous material and system for gas adsorption and storage. In usual constructal theory, a tree branching is postulated for the channels or flow-paths or conductors, usually a dichotomic tree （every branch is divided into two ＂daughters＂）. The objective function of the optimization is built from the resistances to mass or heat transport, expressed here as ＂characteristic transport times＂, and the geometric result is expressed as a shape factor of a domain. The optimized shape expresses the compromise between the mass or heat transport characteristics at adjacent scales. Under suitable assumptions, simple analytical scaling laws are found, which relate the geometric and transport properties of different scales. Some challenging geometric problems may arise when applying the constructal approach to practical situations where strong geometric constraints exist. The search for analytical solutions imposes simplifying assumptions which may be at fault, calling for less constraining approaches, for example making only weak assumptions on the branching structure. Some of these challenges are brought forward along this text.

关键词： multiscale fractal constructal optimization flow distribution

Numerical Investigation of Constructal Distributors with Different Configurations

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Chinese Journal of Chemical Engineering 2009年第1期17卷 175-178页

作者：范志伟周兴贵罗灵爱袁渭康 State Key Laboratory of Chemical Engineering East China University of Science and Technology Shanghai 200237 China laboratoire Optimisation de la conception et Ingenierie de I'Environnement Universite de Savoie Savoie Technolac 73376 France

Seven distributors with different configurations are designed and optimized by constructal approach. Their flow distribution performance and energy dissipation are investigated and compared by computational fluid dynamics （CFD） simulation. The reliability of CFD simulation is verified by experiments on the distributor that has all distributing rectangle channels on a plate. The results show that the symmetry of the distributing channels has decisive influence on the performance of flow distribution. Increasing the generations of channel branching will improve the flow distribution uniformity, but on the other hand increase the energy dissipation. Among all the seven constructal distributors, the distributor that has dichotomy configuration, Y-type junctions and straight interconnecting channels, is recommended for its better flow distribution performance and less energy dissipation.

关键词： constructal distributor configuration flow distribution energy dissipation

A roadmap for security challenges in the Internet of Things

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Digital Communications and Networks 2018年第2期4卷 118-137页

作者： Arbia Riahi Sfar Enrico Natalizio Yacine Challal Zied Chtourou VRIT Lab - Military Academy Nabeul Tunisia Sorbonne Universites Universite de technologie de Compiegne CNRS Heudiasyc UMR 7253 CS 60319 60203 Compiegne Cedex France laboratoire de Methodes de conception de Systemes (LMCS) Ecole Nationale Superieure d'Informatique (ESI) Centre de Recherche sur I'Information Scientifique et Technique (CERIST) Algiers Algeria

Unquestionably, communicating entities （object, or things） in the Internet of Things （IoT） context are playing an active role in human activities, systems and processes. The high connectivity of intelligent objects and their severe constraints lead to many security challenges, which are not included in the classical formulation of security problems and solutions. The Security Shield for IoT has been identified by DARPA （Defense Advanced Research Projects Agency） as one of the four projects with a potential impact broader than the Internet itself. To help interested researchers contribute to this research area, an overview of the loT security roadmap overview is presented in this paper based on a novel cognitive and systemic approach. The role of each component of the approach is explained, we also study its interactions with the other main components, and their impact on the overall. A case study is presented to highlight the components and interactions of the systemic and cognitive approach. Then, security questions about privacy, trust, identification, and access control are discussed. According to the novel taxonomy of the loT framework, different research challenges are highlighted, important solutions and research activities are revealed, and interesting research directions are proposed. In addition, current stan dardization activities are surveyed and discussed to the ensure the security of loT components and applications.

关键词： Internet of Things Systemic and cognitive approach Security Privacy Trust Identification Access control