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The Teodorescu Operator in Clifford Analysis

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Chinese Annals of mathematics,Series B 2012年第4期33卷 625-640页

作者： F.BRACKX h.De SChePPeR m.e. LUNA-eLIZARRARS m.ShAPIRO Clifford Research Group Faculty of Engineering and Architecture Ghent University Belgium Instituto Politcnico Nacional mexico City Mexico

euclidean Clifford analysis is a higher dimensional function theory centred around monogenic functions, i.e., null solutions to a first order vector valued rotation in- variant differential operator called the Dirac operator. more recently, hermitian Clifford analysis has emerged as a new branch, offering yet a refinement of the euclidean case; it focuses on the simultaneous null solutions, called hermitian monogenic functions, to two hermitian Dirac operators and which are invariant under the action of the unitary group. In euclidean Clifford analysis, the Teodorescu operator is the right inverse of the Dirac operator __0. In this paper, Teodorescu operators for the hermitian Dirac operators c9~_ and 0_~, are constructed. moreover, the structure of the euclidean and hermitian Teodor- escu operators is revealed by analyzing the more subtle behaviour of their components. Finally, the obtained inversion relations are still refined for the differential operators is- suing from the euclidean and hermitian Dirac operators by splitting the Clifford algebra product into its dot and wedge parts. Their relationship with several complex variables theory is discussed.

关键词： Clifford analysis Teodorescu operator Dirac operator

Nonlinear Dust Acoustic Waves in Dissipative Space Dusty Plasmas with Superthermal electrons and Nonextensive Ions

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Communications in Theoretical Physics 2016年第5期65卷 606-612页

作者： A.m.el-hanbaly e.K.el-Shewy m.Sallah h.F.Darweesh Theoretical Physics Research Group Physics Department Faculty of Science Mansoura University Department of Physics Taibah University

The nonlinear characteristics of the dust acoustic(DA)waves are studied in a homogeneous,collisionless,unmagnetized,and dissipative dusty plasma composed of negatively charged dusty grains,superthermal electrons,and nonextensive *** pseudopotential technique has been employed to study the large amplitude DA ***(Sagdeev pseudopotential)has an evidence for the existence of compressive and rarefractive *** global features of the phase portrait are investigated to understand the possible types of solutions of the Sagdeev *** the other hand,the reductive perturbation technique has been used to study small amplitude DA waves and yields the Korteweg-de Vries-Burgers(Kd V-Burgers)equation that exhibits both soliton and shock *** behavior of the obtained results of both large and small amplitude is investigated graphically in terms of the plasma parameters like dust kinematic viscosity,superthermal and nonextensive parameters.

关键词： Sagdeev pseudopotential KdV-Burgers equation soliton and shock waves reductive perturbation dust kinematic viscosity

Numerical study on polymer nanofibers with electrically charged jet of viscoelastic fluid in electrospinning process

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Journal of Central South University 2017年第10期24卷 2275-2280页

作者： P.Valipour h.Zaersabet m.hatami Ali Zolfagharian S.e.Ghasemi Department of Textile and Apparel Qaemshahr BranchIslamic Azad UniversityQaemshahrIran Department of mechanical engineering Esfarayen University of TechnologyEsfarayenNorth KhorasanIran School of engineering Deakin UniversityGeelongVictoria 3216Australia Young Researchers and elite Club Sari BranchIslamic Azad UniversitySariIran

electrospinning is a useful and efficient technique to produce polymeric nanofibers. Nanofibers of polymers are electrospun by creating an electrically charged jet of polymer solution. Numerical study on non-Newtonian and viscoelastic jets of polymer nanofibers in electrospinning process is presented in this work. In particular, the effect of non-Newtonian rheology on the jet profile during the electrospinning process is examined. The governing equations of the problem are solved numerically using the Keller-Box method. The effects of yield stress and power-law index on the elongation, velocity, stress and total force are presented and discussed in detail. The results show that by increasing the values of yield stress, the fluid elongation is reduced significantly.

关键词： nanofibers electrospinning electrically charged jet viscoelastic fluid synthetic polymers

An Iterative Domain Decomposition Algorithm for the Grad(div)Operator

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Communications in Computational Physics 2009年第2期5卷 391-397页

作者： e.Ahusborde m.Azaıez m.O.Deville e.h.mund TReFLe (UMR CNRS 8505)Ecole Nationale Superieure de Chimie et de Physique de BordeauxPessacFrance Laboratory of Computational engineering Ecole Polytechnique Federale de Lausanne1015 LausanneSwitzerland Unite de Thermodynamique UCL1348 Louvain-La-NeuveBelgium

This paper describes an iterative solution technique for partial differential equations involving the grad(div)operator,based on a domain *** are performed to solve the solution on the *** identify the transmission relationships through the *** relate the approach to a Steklov-Poincare operator,and we illustrate the performance of technique through some numerical experiments.

关键词： Domain decomposition grad(div)operator stable approximation iterative substructuring method Steklov-Poincar´e operator

high Gain Predictions for Ni-Like Ta Ions

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Chinese Physics Letters 2013年第11期30卷 80-83页

作者： Wessameldin S.Abdelaziz A.A.Farrag h.m.hamed mai e.Ahmed National Institute of Laser enhanced Sciences Cairo UniversityGizaEgypt Faculty of Science Cairo UniversityGizaEgypt environmental Affairs Agency(eeAA) Egypt

Atomic structure data and effective collision strengths for 1s^(2)2s^(2)2p^(6)3s^(2)3p^(6)3d^(10) and 54 fine-structure levels are contained in the configurations 1s^(2)2s^(2)2p^(6)3s^(2)3p^(6)3d^(9)4l(l=s,p,d,f)for the nickel-like Ta *** data are used in the determination of the reduced population for the 55 fine structure levels over a wide range of electron densities(from 10^(21) to 10^(23))and at various electron plasma *** gain coefficients for those transitions with a positive population inversion factor are determined and plotted against the electron density.

关键词： density nickel structure

Design of area and power efficient Radix-4 DIT FFT butterfly unit using floating point fused arithmetic

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Journal of Central South University 2016年第7期23卷 1669-1681页

作者： Prabhu e mangalam h Karthick S Department of electronics and Communication engineering Amrita School of EngineeringCoimbatore Amrita Vishwa Vidyapeetham Amrita University Department of electronics and Communication engineering Sri Krishna College of Engineering and Technology Department of electronics and Communication engineering Bannari Amman Institute of Technology

In this work, power efficient butterfly unit based FFT architecture is presented. The butterfly unit is designed using floating-point fused arithmetic units. The fused arithmetic units include two-term dot product unit and add-subtract unit. In these arithmetic units, operations are performed over complex data values. A modified fused floating-point two-term dot product and an enhanced model for the Radix-4 FFT butterfly unit are proposed. The modified fused two-term dot product is designed using Radix-16 booth multiplier. Radix-16 booth multiplier will reduce the switching activities compared to Radix-8 booth multiplier in existing system and also will reduce the area required. The proposed architecture is implemented efficiently for Radix-4 decimation in time(DIT) FFT butterfly with the two floating-point fused arithmetic units. The proposed enhanced architecture is synthesized, implemented, placed and routed on a FPGA device using Xilinx ISe tool. It is observed that the Radix-4 DIT fused floating-point FFT butterfly requires 50.17% less space and 12.16% reduced power compared to the existing methods and the proposed enhanced model requires 49.82% less space on the FPGA device compared to the proposed design. Also, reduced power consumption is addressed by utilizing the reusability technique, which results in 11.42% of power reduction of the enhanced model compared to the proposed design.

关键词： floating-point arithmetic floating-point fused dot product Radix-16 booth multiplier Radix-4 FFT butterfly fast fouriertransform decimation in time

enhancing fault-clearing algorithm for renewable-energy-based distribution systems using artificial neural networks

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Clean energy 2024年第5期8卷 97-116页

作者： Rania G.mohamed m.A.ebrahim Shady h.e.Abdel Aleem electrical engineering Department Institute of Aviation Engineering and TechnologyGiza12658Egypt electrical engineering Department Faculty of Engineering at ShoubraBenha UniversityCairo11629Egypt

Integrating small and large-scale photovoltaic(PV)solar systems into electrical distribution systems has become mandatory due to increased electricity bills and the concern for limiting greenhouse ***,the reliable and efficient operation of PV-based distribution systems can be confronted by the intermittence and high variability of solar sources and their consequential *** this regard,this article suggests a moderated fault-clearing strategy based on the incremental conductance–maximum power point tracking(IC–mPPT)technique and artificial neural networks(ANNs)to enhance fault detection,localization,and restoration pro-cesses in PV-based distribution *** proposed strategy leverages IC–mPPT to ensure optimal power generation from the PV solar system,even in the presence of *** tracking the maximum power point,the algorithm maintains the performance of the system and mitigates against the impact of faults on the output ***,an ANN is employed to improve fault detec-tion and localization *** developed ANN-based moderated fault-clearing strategy is trained using historical data and fault scenarios,enabling it to recognize fault patterns and make informed decisions through extensive simulations and comparisons with traditional fault-clearing *** accomplish this study,benchmarks in PV-based distribution systems are constructed and em-ployed using the mATLAB®/Simulink®software ***,to validate the efficacy of the developed ANN-based moderated fault-clearing strategy,a real case study of a 1-mW PV-based distribution system in an industrial field located in Giza governorate,egypt,is tested and *** obtained results demonstrate the effectiveness of the IC–mPPT and ANN-based moderated fault-clearing strategy in achieving faster fault detection,precise fault localization,and efficient restoration in PV solar-based dis-tribution systems while preserving maximum power extraction under small and larg

关键词： photovoltaic solar systems fault-clearing algorithm incremental conductance renewable energy artificial neural network maximum power point tracking

The INFLUeNCe OF ISLAND-INDUCeD STRAIN ON The Si SURFACe mORPhOLOGY IN Ge-Si mULTILAYeRS: A TRANSmISSION eLeCTRON mICROSCOPY STUDY

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Acta metallurgica Sinica(english Letters) 2005年第3期18卷 228-236页

作者： h.m.Lu e.Spiecker W.Jaeiger L.Vescan Centerformicroanalysis FacultyofEngineeringChristian-Albrechts-UniversityKielKaiserstraβe2Kiel24143Germany／／StateKeyLaboratoryofSiliconMaterialsZhejiangUniversityHangzhou310027China Centerformicroanalysis FacultyofEngineeringChristian-Albrechts-UniversityKielKaiserstraβe2Kiel24143Germany InstitutfürSchichtenundGrenzflaechen ForschungszentrumJülichGmbHJülich52425Germany

Growth and ordering of coherently strained Ge-rich islands in Ge/Si single layer and multilayer systems and the influence of island arrangements on the evolutio n of the surface morphology of Si cap layers during deposition by low-pressure c hemical vapour deposition(LPCVD) on Si(001) substrates at 700℃ have been invest igated by Tem of cross-section and plan-view specimens. At distances between the Ge layers of 35-50nm, vertical order of GeSi islands is observed for Ge-Si bila yer systems and for Ge-Si multilayer systems consisting of 5 layer pairs whereas lateral ordering parallel to substrate directions is observed for the lat ter case only. In agreement with earlier results the vertical ordering in the mu ltilayer system can be understood as result of the elastic interaction between i sland nuclei forming in the layers with close islands in a buried layer below. T he lateral ordering along may be attributed to the anisotropy of the elast ic interaction. Characteristic for all Si surfaces are the spatial correlation b etween the presence of island-induced lattice strain and the appearance of array s of larger square-shaped pyramids with distinct faceting and facet edges along . The results reflect the importance of the control of growth parameters an d of the island-induced strain state for the evolution of the Si top layer surfa ce morphology during LPCVD growth.

关键词： Si-Ge heteroepitaxy surfaces strain nanostructures transmission electron microscopy

Traces of Defects in the electronic Structure of Porous Ni—Ti Alloys

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Journal of materials Science & Technology 2013年第4期29卷 344-348页

作者： O.m.Ozkendir e.Cengiz e.Tirasoglu mehmet Kaya I.h.Karahan N.Orhan Tarsus Technical Faculty of education Mersin UniversityTarsusTurkey Institute for molecular Science UVSOR FacilityOkazaki 444-8585Japan Science Faculty Department of PhysicsKaradeniz Technical UniversityTrabzonTurkey Vocational School Adiyaman University.Adiyaman 02040Turkey Department of mechanical engineering Texas A&M UniversityCollege StationTX 77843USA Faculty of Arts and Sciences Department of PhysicsMustafa Kemal UniversityHatayTurkey Faculty of Technology Department of Metallurgy and Material EngineeringFirat UniversityElazigTurkey

The electronic structures of Ni-Ti shape-memory alloy samples were investigated by X-ray absorption fine structure （XAFS） spectroscopy both experimentally and theoretically. In the experimental section, the samples were measured at low temperature to determine the persistent traces of both preheating process and atomic concentration effects on the crystal and electronic structure by X-ray absorption near-edge structure （XANeS） spectroscopy. As a second step, the extended-X-ray absorption fine structure （eXAFS） calculations, which are based on different choices of one electron potentials according to Ti coordinations by using the real space multiple scattering method FeFF 8.2 code, were performed. The crystallographic and electronic structures of the porous Ni-Ti alloys were tested at various temperatures ranging from 5 to 1323 K.

关键词： electronic structure Porous Ni-Ti alloys Shape memory effect Transition metals