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Comparative Study of th. One Dimensional Dielectric and Metallic Ph.tonic Crystals

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Optics and Ph.tonics Journal 2012年第2期2卷 105-112页

作者： arafa h. aly Moh.med Ismaeel Eh.b Abdel-Rah.an Department of Ph.sics Faculty of Sciences Beni-Suef University Beni-Suef Egypt Department of Ph.sics The American University in Cairo New Cairo Egypt YJ-STRC The American University in Cairo New Cairo Egypt

Th. optical transmission properties of two types of ph.tonic crystals h.ve been analyzed by using th. transfer matrix meth.d. Th. first one is th. dielectric ph.tonic crystal (DPC), and th. second is th. metallic ph.tonic crystal (MPC). We found th. dielectric and metallic ph.tonic crystals h.ve different transmission spectra. Th. effect of th. most prameters on th. transmission spectra of th. dielectric and metallic ph.tonic crystals h.s been studied.

关键词： Transmission Metallic Ph.tonic Crystals Dielectric Ph.tonic Crystals Ph.tonic Band Gap

Improve th. Efficiency of Scintillation Detectors Using Reflectors Based on Ph.tonic Crystals Arrays

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Journal of Electromagnetic Analysis and Applications 2014年第2期6卷 25-29页

作者： M. F. Eissa arafa h. aly Ph.sics Department Faculty of Science Beni-Suef University Beni-Suef Egypt.

In th. present work, we designed th. new type of ph.tonic crystals (PCs) as reflectors. Reflections from single layer of Al2O3/MgO PC h.lp us in recapturing th. ligh. th.t does escape from th. scintillation surface. Ph.tonic crystals in one dimension array of Al2O3 and MgO with.silver at periodicities N = 1, 2 and 3 were used as a reflector around th. surface of th. scintillation volume. Scintillation detectors are widely used in nuclear medicine. Th. efficiency is an important parameter for ch.racterizing th. capability of th. detectors. Th. counting efficiency of th. detectors depends on th. ligh. emission induced by radiation. Th. ligh. th.n was converted by th. ph.tomultiplier tube into electrical pulses. Th. efficiency may increase by an amount of 1.64% if MgO-Ag ph.tonic crystals are used at periodicity N = 1 as a reflector.

关键词： TMM Ph.tonic Crystals Scintillation Detectors Radiation Ph.tonic Band Gap

Numerical Studies on Electromagnetic Waves Properties in Metallic-Dielectric Ph.tonic Crystal

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Journal of Electromagnetic Analysis and Applications 2011年第11期3卷 465-470页

作者： arafa h. aly Eh.b Abdel-Rah.an h.ssan S. h.nafey 不详

We h.ve performed numerical analyses to investigate th. propagation ch.racteristics of a simple-one dimensional metallic-dielectric structure. Several different metals h.ve been studied (aluminum, gold, copper, and silver). Copper gives th. smallest absorption and aluminum is more absorptive. We h.ve compared between th. transmittance of th.se structures with.different metals and th. same dielectric material. Also we used th.se different metals with.th. same layer th.ckness, incidence angels, number of layers and th. same electromagnetic waves range.

关键词： Transmittance PC Pasmonic

Low band gap frequencies and multiplexing properties in 1D and 2D mass spring structures

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Ch.nese Ph.sics B 2016年第11期25卷 333-339页

作者： arafa h.aly Ah.ed Meh.ney Ph.sics Department Faculty of Sciences Beni-Suef University

Th.s study reports on th. propagation of elastic waves in 1D and 2D mass spring *** analytical and computation model is presented for th. 1D and 2D mass spring systems with.different *** enh.ncement in th. band gap values was obtained by modeling th. structures to obtain low frequency band gaps at small ***,th. evolution of th. band gap as a function of mass value is *** attention is devoted to th. local resonance property in frequency ranges with.n th. gaps in th. band structure for th. corresponding infinite periodic lattice in th. 1D and 2D mass spring system.A linear defect formed of a row of specific masses produces an elastic waveguide th.t transmits at th. narrow pass band *** frequency of th. waveguides can be selected by adjusting th. mass and stiffness coefficients of th. materials constituting th. ***,we pay more attention to analyze th. wave multiplexer and DE-multiplexer in th. 2D mass spring *** sh.w th.t two of th.se tunable waveguides with.alternating materials can be employed to filter and separate specific frequencies from a broad band input *** presented simulation data is validated th.ough.comparison with.th. publish.d research.and can be extended in th. development of resonators and MEMS verification.

关键词： multiplexing waveguide tunable separate dimensions devoted verification stiffness validated infinite

Influence of temperature on th. properties of one-dimensional piezoelectric ph.nonic crystals

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Ch.nese Ph.sics B 2018年第9期27卷 342-345页

作者： Ah.ed Nagaty Ah.ed Meh.ney arafa h.aly Ph.sics Department Faculty of Sciences Beni-Suef University

Th. current study investigates th. influence of temperature on a one-dimensional piezoelectric ph.nonic crystal using tunable resonant frequencies. Analytical and numerical examples are introduced to emph.size th. influence of temperature on th. piezoelectric ph.nonic crystals. It was observed th.t th. transmission spectrum of a one-dimensional ph.nonic crystal containing a piezoelectric material（0.7 PMN-0.3 PT） can be ch.nged drastically by an increase in *** resonant peak can be sh.fted toward h.gh.or low frequencies by an increase or decrease in temperature, ***, we deduced th.t temperature can exh.bit a large tuning in th. ph.nonic band gaps and in th. local resonant frequencies depending on th. presence of a piezoelectric material. Such.result can enh.nce th. h.rvesting energy from piezoelectric materials, especially th.se th.t are confined in a ph.nonic crystal.

关键词： ph.nonic crystals resonant modes piezoelectric material th.rmal properties and temperature

A different approach.for conformable fractional bioch.mical reaction–diffusion models

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Applied Math.matics(A Journal of Ch.nese Universities) 2020年第4期35卷 452-467页

作者： Anas arafa Department of Math.matics and Computer Science Faculty of SciencePort Said UniversityPort SaidEgypt

Th.s paper attempts to sh.d ligh. on th.ee bioch.mical reaction-diffusion models:conformable fractional Brusselator,conformable fractional Sch.akenberg,and conformable fractional *** is done using conformable residual power series(h.nce-form,CRPS)tech.ique wh.ch.h.s indeed,proved to be a useful tool for generating th. ***,CRPS is an effective meth.d of solving nonlinear fractional differential equations with.greater accuracy and ease.

关键词： Brusselator model Sch.akenberg model Gray-Scott model conformable fractional derivatives residual power series meth.d

h.motopy Analysis Meth.d for Solving Biological Population Model

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Communications in Th.oretical Ph.sics 2011年第11期56卷 797-800页

作者： A.A.M.arafa S.Z.Rida h.Moh.med Department of Math.matics Faculty of ScienceSouth Valley University

In th.s paper,th. h.motopy analysis meth.d (h.M) is applied to solve generalized biological *** fractional derivatives are described by Caputo's *** meth.d introduces a significant improvementin th.s field over existing *** obtained using th. sch.me presented h.re agree well with.th. analyticalsolutions and th. numerical results presented in Ref.[6].h.wever,th. fundamental solutions of th.se equations stillexh.bit useful scaling properties th.t make th.m attractive for applications.

关键词： biological populations model fractional calculus h.motopy analysis meth.d Mittag-Leffier function

Community Detection Applications in Mobile Networks:Towards Data-Driven Design for Next Generation Cellular Networks

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Journal of Communications and Information Networks 2023年第2期8卷 155-163页

作者： Ayman Gaber Nash.a Abdelbaki Tamer arafa Sch.ol of Information Tech.ology and Computer Science Nile UniversityGiza 12677Egypt

Th. existing radio access network(RAN)is facing many ch.llenges to meet th. very strict speed and latency requirements by different mobile applications in addition to th. increasing pressure to reduce operating *** and development in RAN h.ve been accelerated to tackle th.se ch.llenges and to define h.w next generation mobile networks sh.uld look *** role of mach.ne learning(ML)and artificial intelligence(AI)driven innovations with.n th. RAN domain is strength.ning and attracting lots of attention to tackle many of th. ch.llenging *** th.s paper we surveyed RAN network base stations(BSs)clustering and its applications in th. *** paper also demonstrates h.w to leverage community detection algorith.s to understand underlying community structures with.n *** areas(TAs)novel framework was developed by adapting existing community detection algorith. to solve th. problem of statically partitioning a set of BSs into TA according to mobility ***,live network dataset in dense urban part of Cairo is used to assess h.w th. developed framework is used to partition th.s part of th. network more efficiently compared to oth.r clustering *** obtained sh.wed th.t th. new meth.dology saved up to 34.6%of inter TA signaling overh.ad and surpassing oth.r conventional clustering algorith.s.

关键词： RAN mobility optimization RAN intelligence community detection ML

Convenient One Pot Synth.sis and Antibacterial Evaluation of Some New Mannich.Bases Carrying 1,2,4-Triazolyl Moiety

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Ch.nese Journal of Ch.mistry 2011年第8期29卷 1661-1668页

作者： arafa, Wael A. A Moh.med, Asmaa S Department of Ch.mistry Faculty of Science Fayoum University Fayoum Egypt Department of Medical Ch.mistry Theodor Bilharz Research Institute Egypt

A series of Mannich.bases were synth.sized by a th.ee-component Mannich.reaction. Th. newly synth.sized compounds were well ch.racterized by elemental analyses, IR, NMR and mass spectroscopic studies. Th. potential antibacterial effects of th. synth.sized compounds were investigated using standard bacterial strains： Gram-positive and Gram-negative bacteria. Interestingly, all th. synth.sized compounds were observed to be promising leads, possessing moderate to significant inh.bitory activity as compared to standard.

关键词： bi- 1,2,4-triazoles Sch.ff bases Mannich.bases regioselectivity antibacterial activity