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Classification of common discharges in outdoor insulation using acoustic signals and artificial neural network

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high Voltage 2019年第4期4卷 333-338页

作者： Satish Polisetty ayman el-hag Shesha Jayram electrical and Computer Engineering Department University of WaterlooWaterlooCanada

Condition monitoring of outdoor insulation systems is crucial to the integrity of distribution and transmission overhead lines and *** objective of this study is to use a commercial acoustic sensor along with artificial neural network(ANN),to classify different typical types of discharges in outdoor insulation ***,ANN was used to distinguish between five common electrical discharges that were generated under controlled ***,this approach was extended to include outdoor ceramic *** types of defects were tested under laboratory conditions,i.e.a crack in the ceramic disc,surface pollution discharge,and corona near the insulator *** a single disc,and three discs connected in an insulator string were tested with respect to these *** both controlled samples and full insulators,a recognition rate of more than 85%was achieved.

关键词： ceramic insulation artificial

Study of Three Different Types of Plasma Ion Sources

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Plasma Science and Technology 2009年第5期11卷 604-608页

作者： M.M.ABDelRAhMAN h.el-KhABEARy Accelerators & Ion Sources Department Nuclear Research CenterAtomic Energy Authority

Three types of plasma ion sources designed, manufactured and optimized in the Accelerators and Ion Sources Department, Nuclear Research Center, Atomic Energy Authority are introduced. Different means were investigated to generate the discharge current and ion beam current extracted from the plasma. The various plasmas described include a DC glow discharge plasma, an arc discharge plasma and a radio frequency discharge plasma.

关键词： ion sources ionization processes sputtering and etching processes

Special Mappings with Central Values on Prime Rings

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Algebra Colloquium 2020年第3期27卷 405-414页

作者： h.el Mir A.Mamouni L.Oukhtite Laboratory of Modelling and Mathematical Structures Department of Mathematics Faculty of Science and Technology of Fez Box 2202University S.M.Ben Abdellah FezMorocco Department of Mathematics Faculty of Science and Technology Box 509-BoutalamineUniversity Moulay IsmailErrachidiaMorocco

In this paper we investigate commutativity of prime rings with involution*of the second kind in which endomorphisms satisfy certain algebraic ***,we provide examples to show that the various restrictions imposed by th... 详细信息

关键词： prime ring involution commutativity derivation generalized derivation

Enhancing asphaltene precipitation modeling by cubic-PR solid model using thermodynamic correlations and averaging techniques

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Petroleum Science 2020年第1期17卷 232-241页

作者： Aktham E.Shoukry Ahmed h.el-Banbi helmy Sayyouh Petroleum Engineering University of WyomingLaramieWYUSA Petroleum Department Faculty of EngineeringCairo UniversityGizaEgypt Petroleum Engineering American University in Cairo(AUC)GizaEgypt

Cubic equation-of-state solid models are one of the most widely used models to predict asphaltene precipitation *** parameters are needed to model precipitation under different pressures and temperatures and are usually obtained through tuning with multi asphaltene onset *** the purpose of enhancing the cubic Peng–Robinson solid model and reducing its dependency on asphaltene experiments,this paper tests the use of aromatics and waxes correlations to obtain these thermodynamic *** addition,weighted averages between both correlations are *** averaging is based on reported saturates,aromatics,resins,asphaltene(SARA)fractions,and wax *** the methods are tested on four oil samples,with previously published data,covering precipitation and onset *** proposed wax-asphaltene average showed the best match with experimental data,followed by a SARA-weighted *** new addition enhances the model predictability and agrees with the general molecular structure of asphaltene molecules.

关键词： Asphaltene precipitation Asphaltene onset pressure Asphaltene precipitation modeling Asphaltene thermodynamics Cubic equation of state

Micro-fabrication of ceramics:Additive manufacturing and conventional technologies

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Journal of Advanced Ceramics 2021年第1期10卷 1-27页

作者： hany hASSANIN Khamis ESSA Amr elShAER Mohamed IMBABY heba h.el-MONGY Tamer A.el-SAYED School of Engineering Canterbury Christ Church UniversityCanterburyCT11QUUK University of Birmingham EdgbastonB152TTUK Kingston University London Penrhyn RoadKingston Upon ThamesSurreyKT12EEUK Department of Mechanical Design Faculty of EngineeringMatariaHelwan UniversityP.O.Box.11718CairoEgypt Jubail University College Mechanical EngineeringKingdom of Saudi Arabia Center for Applied Dynamics Research(CADR) School of EngineeringUniversity of AberdeenAberdeenAB243UEUK

Ceramic materials are increasingly used in micro-electro-mechanical systems(MEMS)as they offer many advantages such as high-temperature resistance,high wear resistance,low density,and favourable mechanical and chemical properties at elevated ***,with the emerging of additive manufacturing,the use of ceramics for functional and structural MEMS raises new opportunities and *** paper provides an extensive review of the manufacturing processes used for ceramic-based MEMS,including additive and conventional manufacturing *** review covers the micro-fabrication techniques of ceramics with the focus on their operating principles,main features,and processed *** that need to be addressed in applying additive technologies in MEMS include ceramic printing on wafers,post-processing at the micro-level,resolution,and quality *** paper also sheds light on the new possibilities of ceramic additive micro-fabrication and their potential applications,which indicates a promising future.

关键词： micro-electro-mechanical system(MEMS) micro-fabrication ceramics micro parts additive manufacturing

A NOTE ON CONTINUATION AND BOUNDEDNESS OF SOLUTIONS OF A NONLINEAR DIFFERENTIAL EQUATION

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Acta Mathematica Scientia 1984年第3期4卷 259-264页

作者： h.el-OW AIDY,A.S.ZAGROUT Math. Dept. Faculty of Science King Abdul Aziz University Jaddah SAUDI ARABIA Math. Dept. Faculty of Science King Abdul Aziz University Jaddah SAUDI ARABIA

A nonlinear second order differential equation is considered. Sufficient conditions for all solutions to be continuable and bounded to the right of an initial value t0≥0 are given.

关键词： A NOTE ON CONTINUATION AND BOUNDEDNESS OF SOLUTIONS OF A NONLINEAR DIFFERENTIAL EQUATION

Bedouin farms in the Saint Katherine mountainous area(South Sinai,Egypt)

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Journal of Mountain Science 2019年第10期16卷 2232-2242页

作者： Kamal h.ShALTOUT Khaled h.el-hAMDI Safaa A.el-MASRY Ebrahem M.EID Botany Department Faculty of ScienceTanta UniversityTanta31527Egypt Soil Department Faculty of AgricultureMansoura UniversityMansoura35516Egypt Biology Department College of ScienceKing Khalid UniversityAbha61321P.O.Box9004Saudi Arabia Botany Department Faculty of ScienceKafr El-Sheikh UniversityKafr El-Sheikh33516Egypt

This study aims to assess the natural and cultivated plant species in 26 Bedouin farms in Saint Katherine Protectorate(SKP),identify their soil and water characteristics,and assess the suitability of these farms for the cultivation of some wild medicinal *** farms were selected to represent wide wadis with deep sand and clay deposits,gorge-like wadis covered with rock fragments of different sizes,spot-like oases,and the Al Q’aa *** TWINSPAN(two-way indicator species analysis)and DCA(detrended correspondence analysis)techniques,the 26 farms were classified into 5 groups(Ⅰ-Ⅴ)based on their floristic composition of wild *** groups reflect an elevation gradient among the farms above sea level from a mean of 119 m to a mean of1,865m.A total of 73 wild species were recorded,with47 in groupⅡ(500-1,000 m)and 25 in group V(>1,700 m).The common target species were Artemisia judaica,Acacia tortilis ***,Origanum syriacum *** and Varthemia montana(34.6%-26.9%).The cultivated speciesnumbered 25,with 17 in groupⅡ(500-1,000 m) andⅡin groupⅣ(1,500-1,700 m).The common fruit trees were olive,grape,fig,apple,palm,almond,apricot and pomegranate(73.0%-42.3%).Based on the soil characteristics,13 farms belong to soil class 2that describes good soils with moderate limitations,and 12 belong to soil class 3 that describes moderately good soils,which can be used regularly for crops after proper treatment.

关键词： Agroforestry Saint Katherine Protectorate Wild medicinal plants elevation gradient Multivariate analysis Wadi Feiran

Numerical Study of Greenhouse Nocturnal heat Losses

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Journal of Thermal Science 2011年第4期20卷 377-384页

作者： F.Berroug E.K.Lakhal M.el Omari M.Faraji h.el Qarnia Laboratoire d'Automatique de l'Environnement et Procédés de Transfert UniversitéCadi AyyadFacultédes Sciences Semlalia-Département de PhysiqueMarrakech-MarocAffiliéau CNRSTURAC 28 Laboratoire de Physique des Materiaux MicroelectroniqueAutomatique et TechniqueDepartement de PhysiquesFaculte des Sciences Ain ChockUniversite Hassan IICasablanca-Maroc

In this study we quantify and analyze different components of nocturnal losses from a heated greenhouse with the presence of vegetation for typical winter weather conditions in Marrakesh-Morocco,using a non linear model,based on the greenhouse heat and mass *** was found that 12% of the total input heat was dissipate as a sensible and latent leakage losses,66% was lost by convective exchange through air-inner *** gain of energy at the inner-cover is dissipated at the outer-cover by radiation(66%)and convection(34%).This results point toward some practical measures to reduce heat losses:increasing air tightness,using covering materials with low-emissivity in the long wave band or putting up an external thermal curtain should provide significant energy savings.

关键词： Greenhouse energy balance heat losses numerical analysis.

Task Scheduling Optimization in Cloud Computing by Rao Algorithm

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Computers, Materials & Continua 2022年第9期72卷 4339-4356页

作者： A.Younes M.Khelnahary Monagi h.Alkinani hamdy h.el-Sayed Faculty of Computers and Information Department of Computer ScienceSohag UniversitySohag82524Egypt Department of Computer Science and Artificial Intelligence College of Computer Science and EngineeringUniversity of JeddahJeddah21959Saudi Arabia

Cloud computing is currently dominated within the space of highperformance distributed computing and it provides resource polling and ondemand services through the ***,task scheduling problem becomes a very important analysis space within the field of a cloud computing environment as a result of user’s services demand modification *** main purpose of task scheduling is to assign tasks to available processors to produce minimum schedule length without violating precedence *** heterogeneous multiprocessor systems,task assignments and schedules have a significant impact on system *** the heuristic-based task scheduling algorithm,the different processes will lead to a different task execution time(makespan)on a heterogeneous computing ***,a good scheduling algorithm should be able to set precedence efficiently for every subtask depending on the resources required to reduce(makespan).In this paper,we propose a new efficient task scheduling algorithm in cloud computing systems based on RAO algorithm to solve an important task and schedule a heterogeneous multiple processing *** basic idea of this process is to exploit the advantages of heuristic-based algorithms to reduce space search and time to get the best *** evaluate our algorithm’s performance by applying it to three examples with a different number of tasks and *** experimental results show that the proposed approach significantly succeeded in finding the optimal solutions than others in terms of the time of task implementation.

关键词： heterogeneous processors RAO algorithm heuristic algorithms task scheduling multiprocessing cloud computing