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Existence of local stable manifolds for some nondensely defined nonautonomous partial functional differential equations

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International Journal of Biomathematics 2019年第8期12卷 127-141页

作者： amor Rebey Department of Mathematics College of Science and Human Studies at Hotat Sudair Majmaah University Al-Majmaah 11952Saudi Arabia ISMAIK Kairouan UniversityTunisia

In this paper,we establish the existence of local stable manifolds for a semi-linear differential equation,where the linear part is a Hille-Yosida operator on a Banach space and the nonlinear forcing term f satisfies the ψ-Lipschitz conditions,where ψ belongs to certain classes of admissible function *** approach being used is the fixed point arguments and the characterization of the exponential dichotomy of evolution equations in admissible spaces of functions defined on the positive half-line.

关键词： Evolution family mild solution exponential dichotomy admissibility of function spaces stable manifolds

Robust SVM-direct torque control of induction motor based on sliding mode controller and sliding mode observer

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Frontiers in Energy 2020年第4期14卷 836-849页

作者： Abdelkarim AMMAR amor BOUREK Abdelhamid BENAKCHA LGEB Laboratory Department of Electrical EngineeringUniversity of BiskraBiskraBP 145Algeria

This paper proposes a design of control and estimation strategy for induction motor based on the variable structure *** describes a coupling of sliding mode direct torque control(DTC)with sliding mode flux and speed *** algorithm uses direct torque control basics and the sliding mode approach.A robust electromagnetic torque and flux controllers are designed to overcome the conventional SVM-DTC draw・backs and to ensure fast response and full reference tracking with desired dynamic behavior and low ripple *** sliding mode controller is used to generate reference voltages in stationary frame and give them to the controlled motor after modulation by a space vector modulation(SVM)*** second aim of this paper is to design a sliding mode speed/flux observer which can improve the control performances by using a sensorless algorithm to get an accurate estimation,and consequently,increase the reliability of the system and decrease the cost of using *** effectiveness of the whole composed control algorithm is investigated in different robustness tests with simulation using Matlab/Simulink and verified by real time experimental implementation based on dS pace 1104 board.

关键词： induction motor direct torque control(DTC) space vector modulation(SVM) sliding mode control(SMC) sliding mode observer(SMO) dS1104

Biologically Inspired Node Generation Algorithm for Path Planning of Hyper-redundant Manipulators Using Probabilistic Roadmap

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International Journal of Automation and computing 2014年第2期11卷 153-161页

作者： Eric Lanteigne amor Jnifene Department of Mechanical Engineering University of Ottawa Department of Mechanical and Aerospace Engineering Royal Military College of Canada

This article describes a biologically inspired node generator for the path planning of serially connected hyper-redundant manipulators using probabilistic roadmap planners. The generator searches the configuration space surrounding existing nodes in the roadmap and uses a combination of random and deterministic search methods that emulate the behaviour of octopus limbs. The strategy consists of randomly mutating the states of the links near the end-effector, and mutating the states of the links near the base of the robot toward the states of the goal configuration. When combined with the small tree probabilistic roadmap planner, the method was successfully used to solve the narrow passage motion planning problem of a 17 degree-of-freedom manipulator.

关键词： Path planning hyper-redundant manipulators probabilistic road map(PRM) quasi-deterministic node generation bi-directional search algorithm.

The Heat Equation for the Dirichlet Fractional Laplacian with Negative Potentials:Existence and Blow-up of Nonnegative Solutions

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Acta Mathematica Sinica,English Series 2017年第7期33卷 981-995页

作者： Ali BEN amor Tarek KENZIZI Department of Mathematics Faculty of Sciences of GabèsUniversity GabèsGabès 6072Tunisia Department of Mathematics Faculty of Sciences of TunisUniversity Tunis EIManarTunis 1001Tunisia

We establish conditions ensuring either existence or blow-up of nonnegative solutions for the heat equation generated by the Dirichlet fractional Laplacian perturbed by negative potentials on bounded sets. The elabora... 详细信息

关键词： Fractional Laplacian heat equation Dirichlet form blow-up

Karyological and morphometric variation of the North African green frog Pelophylax saharicus (Anura) in northeastern Africa

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Current Zoology 2010年第6期56卷 678-686页

作者： Nabil amor Sarra FARJALLAH Slim Ben-YacouB Paolo MERELLA Khaled SAID Unité de Recherche:Génétique Biodiversité et Valorisation des Bioressources UR/09-30Institut Supérieur de Biotechnologie de Monastir Dipartimento di Biologia Strutturale e Funzionale Università di Napoli Federico Ⅱ Laboratory of Terrestrial and Aquatic Systems Ecology. University BADJI Mokhtar Annaba Sezione di Parassitologia e Malattie Parassitarie Dipartimento di Biologia Animale Università degli Studi di Sassar

Morphometric variation ofPelophylax saharicus was analysed using univariate and multivariate statistics, with both traditional and geometric morphometrics, based on 148 specimens from four different geographical localities in Tunisia and Algeria. The results show the existence of three morphotypes in Tunisia and one in Algeria, and indicate a significant degree of variation in morphometric characters between regions. Specimens from the southernmost region have the smallest body size and the greatest morphometrie divergence from other populations. This pattern of morphometric variation probably results from phenotypic plasticity in response to local environmental factors. The results of our chromosomal study （C-, Ag-NOR-, endonuclease digestion, DAPI, CMA3 and Q-banding） reveal this species to exhibit the plesiomorphic Pelophylax karyotype of 2n=26 biarmed chromosomes and NORs on the eleventh pair. Similarities and differences of the North African green frog are discussed in relation to the different forms of data collected （chromosomal, morphometric, ecological） [Current Zoology 56 （6）： 678~586, 2010].

关键词： Green frog Pelophylax saharicus Karyology Morphometric variation Tunisia Algeria

Influences of nanoparticles and chain length on thermodynamic and electrical behavior of fluorine liquid crystals

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Chinese Physics B 2022年第10期31卷 410-416页

作者： Ines Ben amor Lotfi Saadaoui Abdulaziz N.Alharbi Talal M.Althagafi Taoufik Soltani Université Tunis El Manar Laboratoire de Physique de la Matiére Molle et de la Modélisation Electromagnétique2092 Tunis Physics Department College of ScienceTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia

Hydrogen-bonded polar nematic liquid crystal series with the general formula n OBAF(n = 7-12) is studied. The mesomorphic characterization is demonstrated through differential scanning calorimetry(DSC) and polarized optical microscopy(POM). The complexes with short alkyl chains(n = 7, 8) present a wide nematic range and monotropic smectic F mesophase, whereas the longer alkyl chain(n = 10-12) analogues show high melting and low clearing mesomorphic liquid crystals. The thermal range of the mesophase and the birefringence increase with chain length decreasing. Furthermore, the effect of the nanoparticles(LiNbO_(3)) on the thermal and the electrical behavior of 8OBAF are investigated. The presence of LiNbO_(3) nanoparticles increases the conductivity and reduces the resistivity of the complex.

关键词： fluorine liquid crystal polar nematic ferroelectric nanoparticles thermal stability dielectric behavior

Simulator Coupled with Distributed Co-Simulation Protocol for Automated Driving Tests

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Automotive Innovation 2021年第4期4卷 373-389页

作者： Max-Arno Meyer Lina Sauter Christian Granrath Hassen Hadj-amor Jakob Andert Teaching and Research Area Mechatronics in Mobile Propulsion RWTH Aachen UniversityAachenGermany FEV Software and Testing Solutions SAS TrappesFrance

To meet the challenges in software testing for automated vehicles,such as increasing system complexity and an infinite number of operating scenarios,new simulation methods must be ***-loop simulations for automated driving(AD)require highly complex simulation models for multiple controlled vehicles with their perception systems as well as their surrounding *** the realization of such models,different simulation domains must be coupled with ***,widely supported model integration standards such as functional mock-up interface(FMI)lack native support for distributed platforms,which is a key feature for AD due to the computational intensity and platform exclusivity of certain *** newer FMI companion standard distributed co-simulation protocol(DCP)introduces platform coupling but must still be used in conjunction with AD *** part of an assessment framework for AD,this paper presents a DCP compliant implementation of an interoperable interface between a 3D environment and vehicle simulator and a co-simulation platform.A universal Python wrapper is implemented and connected to the simulator to allow its control as a DCP slave.A C-code-based interface enables the co-simulation platform to act as a DCP master and to realize cross-platform data exchange and time synchronization of the environment simulation with other integrated models.A model-in-the-loop use case is performed with the traffic simulator CARLA running on a Linux machine connected to the co-simulation master xMOD on a Windows computer via *** virtual vehicles are successfully controlled by cooperative adaptive cruise controllers executed outside of *** standard compliance of the implementation is verified by exemplary connection to prototypic DCP solutions from 3rd party *** exemplary application demonstrates the benefits of DCP compliant tool coupling for AD simulation with increased tool interoperability,reuse potential,and per

关键词： Distributed co-simulation protocol Co-simulation Automated driving Traffic simulation Tool coupling

Concept development and testing of the UK’s first hydrogenhybrid train(HydroFLEX)

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Railway Engineering Science 2021年第3期29卷 248-257页

作者： Charles Calvert Jeff Allan Peter amor Stuart Hillmansen Clive Roberts Paul Weston Birmingham Centre for Railway Research and Education School of EngineeringUniversity of BirminghamEdgbastonBirmingham B152TTUK Jeff Vehicles Ltd BeavercreekUSA

In October 2018,Porterbrook and the University of Birmingham announced the HydroFLEX project,to demonstrate a hydrogen-hybrid modified train atRail Live *** concept of modifying a Class 319 Electric Multiple Unit was developed,with equipment including a fuel cell stack,traction battery,24 V control system and hydrogen storage elements to be mounted inside one of the *** was followed by procurement of a fuel cell stack,traction batteries,and control equipment,which was then installed inside the train,being fixed to the seat *** substantial change from the concept was the provision of considerably more hydrogen storage than the minimum necessary,providing the train with more potential to be further modified to allow for higher speed mainline *** the Rail Live exhibition where HydroFLEX was demonstrated,numerous modifications were performed to increase the reliability and power of the HydroFLEX train,primarily concerned with modifying the base train logic,with the aim of a successfulmainline *** this effort was a multitude of documentation concerning safety,operations,and approvals to gain approvals from the relevant approvals *** project demonstrated the feasibility of using hydrogen fuel cells as an autonomous fuel for railway propulsion systems,which has the potential for full decarbonisation.

关键词： Hydrogen Fuel cell Hybrid Systems engineering

Kinetics of the Anti-oxidant Response to Salinity in the Halophyte Cakile maritima

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Journal of Integrative Plant Biology 2007年第7期49卷 982-992页

作者： Nader Ben amor Ana Jimenez Wided Megdiche Marianne Lundqvist Francisca Sevilla Chedly Abdelly Centre de Biotechnologie a la Technopole de Borj Cedna Laboratoire d'Adaptation des Plantes sux Stress Abiotiques BP 901 Hammam-Lif 2050 Tunisia Department of Plant Stress Biology and Pathology Centro de Edafologia y Biologia Aplicada del Segura Consejo Superior de Investigaciones Cientificas (CSIC) Apdo. 164 E-30100 Murcia Spain

The effects of NaCl stress on the activity of anti-oxidant enzymes （superoxide dismutase, catalase （CAT）, peroxidase （POD）, ascorbate peroxidase （APX）, monodehydroascorbate reductase, dehydroascorbate reductase （DHAR）, and glutathione reductase （GR））, anti-oxidant molecules （ascorbate and glutathione）, and parameters of oxidative stress （malondialdehyde （MDA）, electrolyte leakage, and H2O2 concentrations） were investigated in Cakile maritima, a halophyte frequent along the Tunisian seashore. Seedlings were grown in the presence of salt （100, 200, and 400 mmol/L NaCl）. Plants were harvested periodically over 20 days. Growth was maximal in the presence of 0-100 mmol/L NaCl. At 400 mmol/L NaCl, growth decreased significantly. The salt tolerance of C. maritima, at moderate salinities, was associated with the lowest values of the parameters indicative of oxidative stress, namely the highest activities of POD, CAT, APX, DHAR, and GR and high tissue content of ascorbate and glutathione. However, prolonged exposure to high salinity resulted in a decrease in anti-oxidant activities and high MDA content, electrolyte leakage, and H2O2 concentrations. These results suggest that anti-oxidant systems participate in the tolerance of C. maritima to moderate salinities.

关键词： anti-oxidant activities ascorbate glutathione halophyte lipid peroxidation salt tolerance.