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Survey of Clustering Schemes in Mobile Ad hoc Networks

Communications and Network 2013年第2期5卷 8-14页

作者： abdelhak bentaleb abdelhak Boubetra Saad Harous Department of Computer Science University of Bachir el Ibrahimi Bordj Bou Arreridj Algeria Faculty of Information Technology United Arab Emirates University P.O Box 17551 Al Ain UAE

Mobile ad-hoc networks (MANETs) are a specific kind of wireless networks that can be quickly deployed without pre- existing infrastructures. They are used in different contexts such as collaborative, medical, military or embedded applications. However, MANETs raise new challenges when they are used in large scale network that contain a large number of nodes. Subsequently, many clustering algorithms have emerged. In fact, these clustering algorithms allow the structuring of the network into groups of entities called clusters creating a hierarchical structure. Each cluster contains a particular node called cluster head elected as cluster head according to a specific metric or a combination of metrics such as identity, degree, mobility, weight, density, etc. MANETs has drawbacks due to both the characteristics of the transmission medium (transmission medium sharing, low bandwidth, etc.) and the routing protocols (information diffusion, path finding, etc.). Clustering in mobile ad hoc networks plays a vital role in improving resource management and network performance (routing delay, bandwidth consumption and throughput). In this paper, we present a study and analyze of some existing clustering approaches for MANETs that recently appeared in literature, which we classify as: Identifier Neighbor based clustering, Topology based clustering, Mobility based clustering, Energy based clustering, and Weight based clustering. We also include clustering definition, review existing clustering approaches, evaluate their performance and cost, discuss their advantages, disadvantages, features and suggest a best clustering approach.

关键词： Clustering Mobile Ad hoc Networks Routing Protocol

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A complete modeling and simulation of DFIG based wind turbine system using fuzzy logic control

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Frontiers in Energy 2016年第2期10卷 143-154页

作者： abdelhak DIDA Djilani BENATTOUS Electrical Engineering Department University of Biskra Biskra 07000Algeria Electrical Engineering Department University of El-Oued El Oued39000 Algeria

The current paper talks about the variable speed wind turbine generation system （WTGS）. So, the WTGS is equipped with a doubly-fed induction generator （DFIG） and two bidirectional converters in the rotor open circuit. A vector control （VC） of the rotor side converter （RSC） offers independent regulation of the stator active and reactive power and the optimal rotational speed tracking in the power maximization operating mode. A VC scheme for the grid-side converter （GSC） allows an independent regulation of the active and reactive power to exchange with the grid and sinusoidal supply currents and keeps the DC-link voltage constant. A fuzzy inference system （FIS） is adopted as an alternative of the conven- tional proportional and integral （PI） controller to reject some uncertainties or disturbance. The performances have been verified using the Matlab/Simulink soft-ware.

关键词： wind turbine generation system (WTGS),doubly-fed induction generator (DFIG) maximum power point tracking (MPPT) vector control (VC) fuzzy logic controller (FLC)

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Doubly-fed induction generator drive based WECS using fuzzy logic controller

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Frontiers in Energy 2015年第3期9卷 272-281页

作者： abdelhak DIDA Djilani BEN ATTOUS Department of Electrical Engineering Biskra University Biskra 07000 Algeria Department of Electrical Engineering El-Oued University El Oued 39000 Algeria

The purpose of this paper is to improve the control performance of the variable speed, constant frequency doubly-fed induction generator in the wind turbine generation system by using fuzzy logic controllers. The control of the rotor-side converter is realized by stator flux oriented control, whereas the control of the grid-side converter is performed by a control strategy based on grid voltage orientation to maintain the DC-link voltage stability. An intelligent fuzzy inference system is proposed as an alternative of the conventional proportional and integral （PI） controller to overcome any disturbance, such as fast wind speed variation, short grid voltage fault, parameter variations and so on. Five fuzzy logic controllers are used in the rotor side converter （RSC） for maximum power point tracking （MPPT） algorithm, active and reactive power control loops, and another two fuzzy logic controllers for direct and quadratic rotor currents components control loops. The performances have been tested on 1.5 MW doubly-fed induction generator （DFIG） in a Matlab/Simulink software environment.

关键词： fuzzy logic wind turbine vector control,doubly-fed induction generator (DFIG)

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Effect of pressure and space between electrodes on the deposition of SiN_(x)H_(y)films in a capacitively coupled plasma reactor

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Chinese Physics B 2021年第5期30卷 507-512页

作者： Meryem Grari CifAllah Zoheir Yasser Yousfi abdelhak Benbrik University Mohamed First Department of PhysicsLETSER LaboratoryOujdaMorocco University Mohamed First Department of MathematicsLANO LaboratoryOujdaMorocco

The fluid model,also called the macroscopic model,is commonly used to simulate low temperature and low pressure radiofrequency plasma *** varying the parameters of the model,numerical simulation allows us to study several cases,providing us the physico-chemical information that is often difficult to obtain *** this work,using the fluid model,we employ numerical simulation to show the effect of pressure and space between the reactor electrodes on the fundamental properties of silicon plasma diluted with ammonia and *** results show the evolution of the fundamental characteristics of the plasma discharge as a function of the variation of the pressure and the distance between the *** examining the pressure-distance product in a range between 0.3 Torr 2.7 cm and 0.7 Torr 4 cm,we have determined the optimal pressure-distance product that allows better deposition of hydrogenated silicon nitride(SiN_(x)H_(y))films which is 0.7 Torr 2.7 cm.

关键词： fluid model numerical simulation SiN_(x)H_(y) capacitively coupled plasma reactor

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Regional averaged controllability for hyperbolic parameter dependent systems

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Control Theory and Technology 2020年第3期18卷 307-314页

作者： Mouna ABDELLI abdelhak HAFDALLAH Faycal MERGHADI Meriem LOUAFI Laboratory of Mathematics Informatics and Systems(LAMIS) University of Larbi Tebessi12002 TebessaAlgeria

The purpose of this paper is to extend the notion of regional controllability for hyperbolic parameter dependent *** key idea is the characterization of the averaged regional control with minimal *** control steers the state average(with respect to such a parameter)towards the desired state only on a given part of the system evolution *** this paper,we give the precis definition and the properties of this new ***,we use an approach based on an extension of the Hilbert uniqueness method devoted to the calculation of the control in two different cases:zone control and pointwise control.

关键词： Parameter dependent system averaged regional controllability averaged control Hilbert uniqueness method minimum energy

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Modeling and control of a permanent magnet synchronous generator dedicated to standalone wind energy conversion system

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Frontiers in Energy 2016年第2期10卷 155-163页

作者： Louar FATEH Ouari AHMED Omeiri AMAR Djellad abdelhak Bouras LAKHDAR Department of Electrical Engineering University of Badji MokhtarAnnaba 23000 Algeria Department of Electrical Engineering University of 20 Aout 1955Skikda Skikda 21000 Algeria

The interest for the use of renewable energies has increased, because of the increasing concerns of the environmental problems. Among renewable energies, wind energy is now widely used. Wind turbines based on an asynchronous generator with a wound rotor present the inconvenience of requiring a system of tings and brooms and a multiplier, inferring significant costs of maintenance. To limit these inconveniences, certain manufacturers developed wind turbines based on synchronous machines with large number of pairs of poles coupled directly with the turbine, avoiding using the multiplier. If the generator is equipped with permanent magnets, the system of rings and brooms is eliminated. The control of the permanent magnet synchronous generator （PMSG） can be affected with the implementation of various techniques of control. This paper presented a new approach mainly based on the control strategy of power production system based on the PMSG. In fact, a mathematical model that simulates the Matlab chain was established with the introduction of control techniques, such as direct control of the torque （DTC） to control the load side converter （LSC）, the control of the speed of the turbine and the DC-bus voltage ensured by PI regulators. To show the performance of the correctors used, some simulation results of the system were presented and analyzed.

关键词： wind turbine permanent magnet synchronous

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Male genital damage in COVID-19 patients:Are available data relevant?

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Asian Journal of Urology 2021年第3期8卷 324-326页

作者： Youssef Kharbach abdelhak Khallouk Urology Department Tangier University HospitalFaculty of MedicineAbdelmalek Essaadi University90000TangierMorocco

Over the past few weeks,we have observed increasing concern about the possible impact of coronavirus disease 2019(COVID-19)which is caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2 virus)on male *** mechanisms of male reproductive damages are still unclear,but it seems that high temperature resulting from persistent fever and triggering a secondary autoimmune response leading to an autoimmune orchitis are the most likely involved ***,angiotensin conversion enzyme 2(ACE2)plays a highly important role in cellular entry for SARS-CoV-2 and male genital system presents high ACE2 *** these preliminary findings suggest that COVID-19 could impact men's reproductive ***,we examined available data including published and unpublished articles to assess the potential risk of COVID-19 in particular on the male reproductive system.

关键词： Coronavirus disease 2019 Severe acute respiratory syndrome coronavirus 2 Male genital system Testis Male infertility

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Pointwise Second-Order Necessary Conditions for Stochastic Optimal Control with Jump Diffusions

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Communications in Mathematics and Statistics 2023年第4期11卷 741-766页

作者： abdelhak Ghoul Mokhtar Hafayed Imad Eddine Lakhdari Shahlar Meherrem Laboratory of Mathematical Analysis Probabilities and OptimizationsUniversity of BiskraPo Box 14507000 BiskraAlgeria Department of Mathematics Yasar UniversityUniversity avenAgaclıYol No.35-57IzmirTurkey

In this paper,we establish a second-order necessary conditions for stochastic optimal control for jump *** controlled system is described by a stochastic differential systems driven by Poisson random measure and an independent Brownian *** control domain is assumed to be *** second-order maximum principle for controlled jump diffusion in terms of the martingale with respect to the time variable is *** proof of the main result is based on variational approach using the stochastic calculus of jump diffusions and some estimates on the state processes.

关键词： Optimal control Stochastic systems with jumps Pointwise second-order necessary condition Maximum principle Variational equation

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Finite element analysis of stress concentrations and failure criteria in composite plates with circular holes

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Frontiers of Mechanical Engineering 2014年第3期9卷 281-294页

作者： abdelhak KHECHAI Abdelhamid GUETTALA Abdelouahab TATI Laboratory of Civil Engineering University of Biskra Biskra 07000Algeria Laboratory of Energy Engineering and Materials University of BiskraBiskra 07000 Algeria

In this study, the （SCF） in cross-and-angle-ply stress concentration factors laminated composite plates as well as in isotropic plates with single circular holes subjected to uniaxial loading is studied. A quadrilateral finite element of four-node with 32 degrees of freedom at each node, previously developed for the bending and mechanical buckling of laminated composite plates, is used to evaluate the stress distribution in laminated composite plates with central circular holes. Based up on the classical plate theory, the present finite element is a combination of a linear isoparametric membrane element and a high precision rectangular Hermitian element. The numerical results obtained by the present element compare favorably with those obtained by the analytic approaches published in literature. It is observed that the obtained results are very close to the reference results, which demonstrates the accuracy of the present element. Additionally, to determine the first ply failure （FPF） of laminated plate, several failure criterions are employed. Finally, to show the effect of E1/E2 ratio on the failure of plates, a number of figures are given for different fiber orientation angles.

关键词： laminated composite plates stress concentration geometric singularity anisotropic effect

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Asymptotic properties of a nonparametric conditional density estimator in the local linear estimation for functional data via a functional single-index model

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Statistical Theory and Related Fields 2022年第3期6卷 208-219页

作者： Fadila Benaissa Abdelmalek Gagui abdelhak Chouaf University Oran 1 Ahmed Ben Bella Oran OranAlgeria Laboratory of Statistics and Stochastic Processes Djillali Liabes UniversitySidi Bel AbbesAlgeria

This paper deals with the conditional density estimator of a real response variable given a functional random variable(i.e.,takes values in an infinite-dimensional space).Specifically,we focus on the functional index model,and this approach represents a good compromise between nonparametric and parametric *** we give under general conditions and when the variables are independent,the quadratic error and asymptotic normality of estimator by local linear method,based on the single-index ***,wecomplete these theoretical advances by some simulation studies showing both the practical result of the local linear method and the good behaviour for finite sample sizes of the estimator and of the Monte Carlo methods to create functional pseudo-confidence area.

关键词： Mean squared error single functional index conditional density function nonparametric estimation local linear estimation asymptotic normality functional data

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