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Mixed sensitivity H_∞ control for LTI systems with varying time delays

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Journal of Systems Engineering and Electronics 2018年第3期29卷 611-617页

作者： ould mohamed mohamed vall College of Computer and Information Sciences Al Jouf University

Designing a robust controller for a system with timevarying delays poses a major challenge. In this paper, we propose a method based on mixed sensitivity H∞ for the control of linear time invariant（LTI） systems with varying time delays. The time delay is assumed bounded and the upper bound is known. In the technique we propose, the delay affecting the plant to be controlled is treated as an unmodeled uncertainty（in form of multiplicative uncertainty）. That uncertainty is approximated and then an H∞based controller, for the plant represented by the multiplicative uncertainty and the nominal model, is calculated. The obtained H∞controller is used to control the LTI systems with varying time delays. Simulation examples are given to illustrate the effectiveness of the proposed method.

关键词： linear time invariant(LTI) systems mixed sensitivity H∞ varying time delay unmodeled uncertainty H∞ control

Heat, Resolvent and Wave Kernels with Multiple Inverse Square Potential on the Euclidian Space R<sup>n</sup>

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Applied Mathematics 2014年第16期5卷 2612-2618页

作者： mohamed vall ould moustapha Unité de Recherche: Analyse EDP et Modélisation (AEDPM) Département de Mathématiques et Informatique Faculté des Sciences et Techniques Universit&#232 des Sciences de Technologie et de la Médecine (USTM) Nouakchott Mauritanie

In this paper, the heat, resolvent and wave kernels associated to the Schr?dinger operator with multi-inverse square potential on the Euclidian space Rn are given in explicit forms.

关键词： Heat Kernel Wave Kernel Resolvent Kernel Multiple-Inverse Square Potential Bessel Function Lauricella Hypergeometric Function

ON SINGULAR EQUATIONS INVOLVING FRACTIONAL LAPLACIAN

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Acta Mathematica Scientia 2020年第5期40卷 1289-1315页

作者： Ahmed YOUSSFI Ghoulam ould mohamed MAHMOUD National School of Applied Sciences Sidi mohamed Ben Abdellah University-Fez Laboratory of Mathematical Analysis and Applications My Abdellah Avenue Road ImouzerP.O.Box 72 Fes-Principale30000FezMorocco National School of Applied Sciences Sidi mohamed Ben Abdellah University-Fez My Abdellah Avenue Road ImouzerP.0.Box 72 Fes-Principale30000FezMorocco

We study the existence and the regularity of solutions for a class of nonlocal equations involving the fractional Laplacian operator with singular nonlinearity and Radon measure data.

关键词： fractional Laplacian singular elliptic equations measure data

Analysis and Control of the Vehicle Roll Dynamics Using Sum of Squares Polynomial Approach

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Journal of Systems Science & Complexity 2024年第6期37卷 2318-2346页

作者： IBEN AMMAR Imen DOUMIATI moustapha TALJ Reine CHOKOR Abbas MACHMOUM mohamed ESEO-IREENA Institut de Recherche en énergie électrique de Nantes Atlantique Sorbonne Universités Université de Technologie de Compiègne CNRS Continental

The safety of vehicle travel relies on good stability performance, making vehicle motion control a vital technology in vehicles. This paper focuses on investigating the impact of roll control on vehicle performance, particularly in terms of avoiding rollover and ensuring lateral stability. By introducing a feedback roll moment, the roll motion can be effectively controlled. The paper considers two roll reference generators: A static one aimed at zero roll, and a dynamic one based on the vehicle's lateral acceleration. The static roll reference generator enhances stability by employing a fixed reference, particularly beneficial during routine driving conditions. In contrast, the dynamic roll reference generator continually adapts the roll angle reference in response to real-time vehicle dynamics and driving conditions. These proposed reference generators can be paired with varying suspension systems — Static reference could be achieved using semi-active suspensions, while the dynamic one is integrated into advanced active suspension systems, offering heightened adaptability and *** address the roll control objectives, this paper proposes a novel sum of squares(SOS) integral polynomial tracking control. The proposed controller satisfies control bounds and considers control constraints during the design phase. The effectiveness and robustness of the proposed control scheme are evaluated through numerical simulations using a full vehicle nonlinear model in Matlab/Simulink. The results of these simulations are compared to super-twisting sliding mode and Lyapunov-based controllers.

关键词： Active suspensions lateral stability polynomial control rollover avoidance SOS approach

PLANNED LEAD TIME OPTIMIZATION IN MATERIAL REQUIREMENT PLANNING ENVIRONMENT FOR MULTILEVEL PRODUCTION SYSTEMS

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Journal of Systems Science and Systems Engineering 2008年第2期17卷 132-155页

作者： Faicel HNAIEN Alexandre DOLGUI mohamed-Aly ould LOULY Industrial Engineering and Computer Science Centre(G2I)Ecole des Mines de St Etienne 158cours Fauriel42023 Saint EtienneFrance King Saud University College of Engineering-Industrial Engineering Department P.O.B 800 Riyadh 11421Kingdom of Saudi Arabia

This paper deals with the problem of planned lead time calculation in a Material Requirement Planning （MRP） environment under stochastic lead times. The objective is to minimize the sum of holding and backlogging costs. The proposed approach is based on discrete time inventory control where the decision variables are integer. Two types of systems are considered： multi-level serial-production and assembly systems. For the serial production systems （one type of component at each level）, a mathematical model is suggested. Then, it is proven that this model is equivalent to the well known discrete Newsboy Model. This directly provides the optimal values for the planned lead times. For multilevel assembly systems, a dedicated model is proposed and some properties of the decision variables and objective function are proven. These properties are used to calculate lower and upper limits on the decision variables and lower and upper bounds on the objective function. The obtained limits and bounds open the possibility to develop an efficient optimization algorithm using, for example, a Branch and Bound approach. The paper presents the proposed models in detail with corresponding proofs and se＇~eral numerical examples. Some advantages of the suggested models and perspectives of this research are discussed.

关键词： Multilevel assembly and production control model planned lead time optimization systems MRP random lead times discrete inventory

Toxicology,biosynthesis,bio-control of aflatoxin and new methods of detection

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Asian Pacific Journal of Tropical Biomedicine 2016年第9期6卷 808-814页

作者： mohamed Amine Gacem Aminata ould El Hadj-Khelil Laboratory of Protection of Ecosystems in Arid and Semi-Arid Area University of Kasdi Merbah Department of Biology Faculty of ScienceUniversity of Amar Tlidji

Mycotoxins and their derivatives since their discoveries and until the present time are behind unspecified economic and medical *** are classified according to their physical–chemical and toxicological characters in the most dangerous row of the *** aflatoxins are in part responsible,of irreversible medical disasters that are not easily manageable such as cancer of the liver and kidneys,and in the other part,of losses in the stored cereal *** on these crucial findings,monitoring of this toxin became imperative in post-harvest food products,during storage,during transformation chain and even during the long phases of *** of this toxin is delivered by detection methods using very advanced technologies to respond in the shortest possible *** addition,the knowledge of factors supporting the biosynthesis of aflatoxins such as the temperature,moisture content,concentration of nitrogen and carbon,and the molecules responsible for the genetic control of the synthesis will be reflected later in the choice of bio-control *** control is currently based on new strategies using the bioactives substances of the plants,the lactic bacteria and some strains of actinomycetes that have good inhibiting activity against aflatoxins with fewer side effects on *** the other hand,this brief review summarizes the results of new studies demonstrating the toxicity of the toxin,new detection methods and bio-control.

关键词： Mycotoxins Aflatoxins Cancer Biosynthesis Bio-controls Detection methods

An Analytical Model for Torus Networks in the Presence of Batch Message Arrivals with Hot-spot Destinations

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International Journal of Automation and computing 2009年第1期6卷 38-47页

作者： Yulei Wu Geyong Min mohamed ould-Khaoua Hao Yin Department of Computing School of Informatics University of Bradford Bradford BD7 1DP UK Department of Computing Science University of Glasgow Glasgow G12 8RZ UK Department of Computer Science Tsinghua University Beijing 100084 PRC

Interconnection networks are hardware fabrics supporting communications between individual processors in multi- computers. The low-dimensional k-ary n-cubes （or torus） with adaptive wormhole switching have attracted significant research efforts to construct high-performance interconnection networks in contemporary multi-computers. The arrival process and destination distribution of messages have great effects on network performance. With the aim of capturing the characteristics of the realistic traffic pattern and obtaining a deep understanding of the performance behaviour of interconneetion networks, this paper presents an analytical model to investigate the message latency in adaptive-routed wormhole-switched torus networks where there exists hot-spot nodes and the message arrivals follow a batch arrival process. Each generated message has a given probability to be directed to the hot-spot node. The average degree of virtual channel multiplexing is computed by the GE/G/1/V queueing system with finite buffer capacity. We compare analytical results of message latency with those obtained through the simulation experiments in order to validate the accuracy of the derived model.

关键词： Multi-computers interconnection networks non-uniform traffic generalised exponential distribution GE/G/1/V.

Mineralization and Exploration Perspectives in the Oudiane Elkharoub Zone, Birimian Domain, Reguibat Shield, Mauritania

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Open Journal of Geology 2023年第12期13卷 1312-1330页

作者： Hdeid ould Mahmoud mohamed Raji Malika Adjour Isselmou Brahim vall Department of Geology Faculty of Sciences Ben M’sik Hassan II University Casablanca Morocco National Agency for Geological Research and Mining Heritage Nouakchott Mauritania

The Oudiane Elkharoub Zone is one of the major areas of the Reguibat Shield due to its position in the extreme northeast of the Birimian formation (dated between 1.6 and 2.7 Ga) within the Reguibat Shield, coupled with its closeness to with the Archean Domain in the Shield’s southern portion and with the Taoudeni Basin to the east. The results of field mapping, together with chemical (Fire Assay) and XRF (fluorescence spectrometer X-ray) analyses, shows significant Au, Ag, Cu, Pb, Mn, Cr, Ni, Th and Y anomalies in samples taken from the Oudiane Elkharoub Zone. The results of those analyses will allow us to build a geochemistry maps for the anomalous metal for the study area, understand the relationships between different rock units and the mineralization and the mineralization control and their style, such as structural or lithological control. This context reflects a structural control of the Mineralization according to the conducted analyses and the observation on the field. The mineralization auriferous mainly hosted in quartz vein or quartz-carbonate vein with sulfide (pyrrhotite and pyrite) alteration.

关键词： Oudiane Elkharoub Reguibat Shield Birimian Anomalies Mineralization XRF Fire Assay

E-Passport and Building Online Passport Service System

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E-Passport and Building Online Passport Service System

作者： mohamed Lemine ould Nomane（诺曼）武汉理工大学

学位级别：硕士

随着IT技术的发展,生物识别技术已经成为一个研究的热点领域。各国政府都纷纷资助生物识别技术方面的研究,该领域方面的学术会议吸引了政府和业界众多的参与者,理论研究的成果正快速地转换为商业产品。在某种意义上讲,生物识别技术属于...

随着IT技术的发展,生物识别技术已经成为一个研究的热点领域。各国政府都纷纷资助生物识别技术方面的研究,该领域方面的学术会议吸引了政府和业界众多的参与者,理论研究的成果正快速地转换为商业产品。在某种意义上讲,生物识别技术属于理论知识前沿范畴,可以表达复杂的设计问题,因此生物识别技术和RFID技术尤为重要。在此基础上,论文研究电子护照和护照服务系统的构建,电子护照记载了公民的特征信息,是政府及各国海关识别公民身份的重要依据。对电子护照的相关技术以及护照相关信息的管理展开研究,具有较为重要的研究和应用价值。论文主要工作包含两部分：(1)对于包含生物识别和RFID芯片的公民电子护照的论证;(2)使用UML和DOTNET设计并实现了了电子护照的在线服务系统。第一部分首先介绍了生物识别技术和RFID相关技术。概述了几种不同的生物识别技术：虹膜识别、手型识别、指纹识别、视网膜识别和面部识别等技术,综述了PKI和数字签名技术,而后介绍了RFID标签、RFID结构等相关技术。第二部分探讨了如何利用C#、***和UML开发一个在线的护照服务系统,讨论了护照在线服务系统的设计,采用用例图和类图分别描述需求和功能设计,应用概念数据模型和物理数据模型描述数据库设计。

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