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Computers, materials & Continua 2022年第8期72卷 3751-3762页

作者： Ahmed.A.Rosas mona Shokair m.i.Dessouky Department of Electronics and Electrical Communication Engineering Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt

With the obvious throughput shortage in traditional cellular radio networks,Device-to-Device(D2D)communications has gained a lot of attention to improve the utilization,capacity and channel performance of nextgeneration *** this paper,we study a joint consideration of power and channel allocation based on genetic algorithm as a promising direction to expand the overall network capacity for D2D underlaied cellular *** genetic based algorithm targets allocating more suitable channels to D2D users and finding the optimal transmit powers for all D2D links and cellular users efficiently,aiming to maximize the overall system throughput of D2D underlaied cellular network with minimum interference level,while satisfying the required quality of service QoS of each *** simulation results show that our proposed approach has an advantage in terms of maximizing the overall system utilization than fixed,random,BAT algorithm(BA)and Particle Swarm Optimization(PSO)based power allocation schemes.

关键词： 5G D2D communication spectrum allocation power allocation genetic algorithm optimization BAT-optimization particle swarm optimization

The influence of Thomson effect and inclined loads in an electro-magneto-thermoelastic solid with voids under green-Naghdi theories

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Journal of Ocean Engineering and Science 2018年第3期3卷 253-264页

作者： Elsayed m.Abd-Elaziz mohamed i.m.Hilal Department of mathematics Zagazig UniversityFaculty of ScienceP.O.Box 44519ZagazigEgypt

The present investigation deals with the 2-dimensional deformation in a homogeneous thermoelastic solid with voids subjected to inclined *** heat conduction equation is affected with the Thomson *** basic governing equations are modified by using Green-Naghdi theory of *** normal mode analysis technique is used to obtain the components of stress,strain,temperature,induced magnetic field and change in volume fraction *** variations of these quantities have been depicted graphically in the Green-Naghdi theories of type-ii and iii for an insulated *** numerical calculations,the effect of Thomson parameter and angle of inclination on a homogeneous,isotropic,electro-magneto-thermoelastic material with voids is revealed and discussed.

关键词： Electro-magneto-thermoelasticity Normal mode method inclined loads Voids Thomson effect Green-Naghdi theory

Simultaneous scheduling of machines and automated guided vehicles in flexible manufacturing systems using genetic algorithms

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Journal of Central South University 2011年第5期18卷 1473-1486页

作者： i.A.Chaudhry S.mahmood m.Shami National University of Sciences & Technology (NUST) IslamabadPAKISTAN

The problem of simultaneous scheduling of machines and vehicles in flexible manufacturing system (FmS) was addressed.A spreadsheet based genetic algorithm (GA) approach was presented to solve the problem.A domain independent general purpose GA was used,which was an add-in to the spreadsheet *** adaptation of the propritary GA software was demonstrated to the problem of minimizing the total completion time or makespan for simultaneous scheduling of machines and vehicles in flexible manufacturing *** results are presented for a benchmark with 82 test problems,which have been constructed by other *** achieved results are comparable to the previous *** proposed approach can be also applied to other problems or objective functions without changing the GA routine or the spreadsheet model.

关键词： automated guided vehicles (AGVs) scheduling job-shop genetic algorithms flexible manufacturing system (FmS) spreadsheet

Lubricant flow in thin-film elastohydrodynamic contact under extreme conditions

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Friction 2016年第4期4卷 380-390页

作者： P.SPERKA i.KRUPKA m.HARTL Faculty of mechanical Engineering Brno University of Technology Technicka 2896/2 Brno 61669 Czech Republic

To further extend knowledge about fluid film friction in elastohydrodynamic contact,it is important to examine how lubricant *** this paper,several film thickness results obtained by interferometry technique for different kinds of experiments were analyzed and discussed based on lubricant flow *** of two steady-state and two transient experiments are *** speed profiles that can explain observed film thickness distributions were *** is shown that major part of present experiments can be explained by a single speed profile known as a plug *** finding is in contradiction to usual linear speed profile predicted by Reynolds equation.

关键词： fluid film friction speed profile flow rate continuity lubricant rheology plug flow

Conditional Probability Approach for Fault Detection in Photovoltaic Energy Farms

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Computer Systems Science & Engineering 2022年第9期42卷 1109-1120页

作者： Nagy i.Elkalashy ibrahim B.m.Taha Electrical Engineering Department Faculty of EngineeringMenoufia University32511Egypt Electrical Engineering Department College of EngineeringTaif University21944Saudi Arabia

Detection of electric faults in photovoltaic (PV) farms enhances a sustainable service continuity of farm energy generation. in this paper, a probabilisticfunction is introduced to detect the faults in the PV farms. The conditional probability functions are adopted to detect different fault conditions such as internalstring faults, string-to-string faults, and string-to-negative terminal faults. As thediodes are important to make the PV farms in-service safely during the faults,the distribution currents of these faults are evaluated with different concepts ofdiode consideration as well as without considering any diode installation. Thispart of the study enhances the diode utilization in the PV farms concerning theprotection point of view. The PV string currents are used as inputs to the conditional probability detection algorithms. However, the setting of the fault detectiontechnique is not portable for the other PV systems due to broad ranges of PV system ratings. To accordingly generalize the proposed fault detection algorithm, thePV string currents are first normalized to the total array current for universallyapplying the detection function at different PV string ratings. The limiting faultresistances are evaluated to show the sensitivity of the proposed fault *** results ensure the application of the proposed probabilistic detection functionfor PV farms.

关键词： Photovoltaic farm fault detection conditional probability diodes

Aspect of the specialty metals potentials of pegmatites in western Oban massif,SE Nigeria:A preliminary geochemical approach

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Chinese Journal Of Geochemistry 2012年第4期31卷 355-361页

作者： Oden m.i. igonor E.E. Department of Geology University of CalabarP.M.B.1115 CalabarNigeria Petra Prospectors Limited Nigeria

minerals in general and rare-metals in particular are of invaluable importance in the development and industrialization of any *** is true as they could affect a nation's national income,employment ratio,Gross National Product,and its entire *** study area(western Oban massif-SE Nigeria) was investigated for its specialty metals bearing potentials because of(1) its geology,which is similar to other specialty metals bearing areas of the world;(2) past works,which points to the area as a likely source of economic deposit of such metals;and(3) the soaring cost of these rare metals in the light of recent upsurge in global information/telecommunication *** from the study,show that only cesium(Cs) and beryllium(Be) show minute signs or indications of enrichment if properly *** these metals should be studied in details to ascertain their economic *** rocks are too deficient in the other rare-metals(lithium,zirconium,strontium,tantalite,niobium,tungsten,gallium,and chromium) to warrant further analysis.

关键词：特种金属尼日利亚地球化学方法电位伟晶岩稀有金属矿地块国民生产总值

Screening the insecticidal Efficacy of Nano ZnO Synthesized via in-situ Polymerization of Crosslinked Polyacrylic Acid as a Template

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Journal of materials Science & Technology 2012年第11期28卷 961-968页

作者： m. mekewi Ahmed Shebl A.i. imam m.S. Amin T. Albert Chemistry Department Faculty of Science Ain Shams University Plants Protection Department Desert Research Center

Nano zinc oxide （ZnO） is a very useful and important material in many industrial and biological applications. in the present work, ZnO was synthesized by post thermal degradation of the precursor ＂zinc acetate di-hydrate＂ templated in crosslinked polyacrylic acid （PAA）. The crosslinked PAA template was prepared through an in-situ polymerization process adopted in presence of ammonium per sulphate, as an initiator, and N, Nt- methylene bis-acrylamide as the crosslinker. Variation of preparation parameters and their impact on the oxide stoichiometry, crystal structure, crystallite size and surface texture of the oxide were investigated. Energy dispersive X-ray technique （EDX）, X-ray diffraction （XRD） and scanning electron microscopy （SEm） were convincingly used to reveal the oxide structural features and characteristics. The performed bioassay tests indicated the efficacy of this method of preparation to produce nano ZnO with novel insecticidal activity against the greater wax moth, Galleria rnellonella.

关键词： Nano ZnO in-situ polymerization Polymer template insecticide Bioassay Galleria mellonella

Numerical analysis and centrifugal modeling of LNAPLs transport in subsurface system

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Progress in Natural Science:materials international 2006年第4期16卷 416-424页

作者： LO i.m.C. mEEGODA J.N. Department of Civil Engineering Hong Kong University of Science and Technology Hong Kong SARChina Department of Civil and Environmental Engineering New Jersey institute of Technology USA

The transport of non-aqueous phase liquids (NAPLs) in unsaturated soils and groundwater is an important research topic in geo-environmental engineering. in this paper, the mechanism of light NAPLs (LNAPLs) transport in subsurface system is briefly introduced, and the mass transport equations, fluid flow equations, and the constitutive model of relative permeability - saturation - capillary pressure are discussed. Then the numerical method is introduced to simulate the multiphase flow problems in porous media, and the tempospatial distribution of LNAPLs is obtained. moreover, different boundary conditions are employed in numerical simulation to investigate its effect on transport behavior. To verify the numerical data, centrifugal tests are conducted to model the LNAPLs migration in unsaturated soils and groundwater. The calculation results are agreeable with the experimental findings of centrifugal modeling, which indicates that LNAPLs from leaking point move downwards due to gravity force, and form a high concentration zone above the capillary fringe, and then spread out laterally along the groundwater table. Some LNAPL enters groundwater system to further migrate. The combination of numerical simulation and centrifuge modeling can be a useful means to study the transport behavior of LNAPLs in subsurface system.

关键词： geo-environmental engineering subsurface contamination multiphase flow light non-aqueous phase liquids (LNAPLs) centrifugal modeling technique numerical simulation.

measurement of mass attenuation coefficients,effective atomic numbers,and electron densities for different parts of medicinal aromatic plants in low-energy region

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Nuclear Science and Techniques 2018年第10期29卷 200-209页

作者： m.i.Sayyed F.Akman i.H.Geccbesler H.O.Tekin Department of Physics University of TabukTabuk 009662Saudi Arabia Department of Electronic Communication Technology Vocational School of Technical SciencesBingo¨l University12000 Bingo¨lTurkey Department of Occupational Health and Safety Faculty of Health ScienceLaboratory of Natural Product ResearchBingo¨l University12000 Bingo¨lTurkey Department of Radiotherapy Uskdar University34662 I stanbulTurkey

The mass attenuation coefficients(l/q) for different parts(root, flower, stem, and leaf) of three medicinal aromatic plants(Teucrium chamaedrys L. subsp. sinuatum,Rheum ribes, and Chrysophthalmum montanum) were measured using an ^(241)Am photon source in a stable geometry and calculated using the monte Carlo N-Particle Transport Code System-extended(mCNPX) code and the WinXCOm program. The experimental and theoretical mCNPX and WinXCOm values exhibited good *** measured mass attenuation coefficient values were then used to compute the effective atomic number(Z_(eff))and electron density(N_E) of the samples. The results reveal that S1-S(stem of Teucrium chamaedrys L. subsp. sinuatum) has the highest values of l/q and Zeff.

关键词： medicinal Aromatic plant mCNPX code mass attenuation coefficient Photon WinXCOm

Diffusion of Six-Atom Cu islands on Cu(111)and Ag(111)

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Chinese Physics Letters 2011年第5期28卷 99-102页

作者： Sardar Sikandar Hayat i.Ahmad m.Arshad Choudhry Department of Physics and Astronomy Hazara UniversityMansehra 23100Pakistan Department of Physics The Islamia University of BahawalpurBahawalpur 63120Pakistan

Diffusion of Cu hexamer islands on Cu(111)and Ag(111)is studied using a molecular dynamics simulation technique with many-body potentials obtained from the embedded atom *** are carried out at temperatures 300,500 and 700 K,showing that shape-changing multiple-atom processes are more helpful for the diffusion rather than concerted motion of *** plots of the diffusion coefficients provide effective energy barrier values of 161.29±5 meV for Cu(111)and 179.34±5 meV for Ag(111)*** 700K,one pop-up atom among island atoms is observed with correlative changes in the position and shape of the lower-layer adatoms.

关键词： Cu(111) method Diffusion