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Journal of Ocean Engineering and science 2022年第5期7卷 492-497页

作者： Noufe H.Aljahdaly s.A.El-Tantawy Department of Mathematics Faculty of Sciences and Arts-Rabigh campusKing Abdulaziz UniversityJeddahSaudi Arabia Department of Physics Faculty of SciencePort Said UniversityPort Said 42521Egypt Research Center for Physics(RCP) Department of PhysicsFaculty of Science and ArtsAl-MikhwahAl-Baha UniversitySaudi Arabia

A novel approximate analytical solution to the linear damped Kawahara equation using a suitable hypothesis is reported for the first *** on the exact solutions(such as solitary waves,cnoidal waves,etc.)of the undamped Kawahara equation,the dissipative nonlinear structures like dissipative solitons and cnoidal waves are *** obtained solution is considered a general solution,i.e.,it can be applied for studying the properties of all dissipative traveling waves described by the linear damped Kawahara *** technique is not limited to solve the linear damped Kawahara equation only,but it can be used for solving a large number of non-integrable evolution equations related to the realistic natural ***,the maximum global residual error in the whole space-time domain is estimated for checking the accuracy of the obtained *** obtained solutions can help many researchers in explaining the ambiguities about the mechanisms of propagation of nonlinear waves in complex systems such as seas,oceans,plasma physics,and much more.

关键词： semi-analytical solutions Damped Kawahara equation A collisional plasma Dissipative Kawahara solitons and cnoidal waves

Affine transformation of virtual 3D object using 2D localization of fingertips

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Virtual Reality & Intelligent Hardware 2020年第6期2卷 534-555页

作者： Mohammad Mahmudul ALAM s.M.Mahbubur RAHMAN Department of Electrical and Electronic Engineering Bangladesh University of Engineering and TechnologyDhaka 1000Bangladesh

Background Interactions with virtual 3D objects in the virtual reality(VR)environment using the gesture of fingers captured in a wearable 2D camera have emerging applications in *** This paper presents an approach of a two-stage convolutional neural network,one for the detection of hand and another for the *** purpose of VR environments is to transform a virtual 3D object with affine parameters by using the gesture of thumb and index *** To evaluate the performance of the proposed system,one existing,and another developed egocentric fingertip databases are employed so that learning involves large variations that are common in *** results show that the proposed fingertip detection system outperforms the existing systems in terms of the precision of *** The interaction performance of the proposed system in the VR environment is higher than that of the existing systems in terms of estimation error and correlation between the ground truth and estimated affine parameters.

关键词： Affine transformation Detection of fingertips Detection of hand Human-computer interaction Virtual reality

A new insertion sequence for incremental Delaunay triangulation

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Acta Mechanica sinica 2013年第1期29卷 99-109页

作者： Jian-Fei Liu Jin-Hui Yan s.-H. Lo Department of Mechanics and Aerospace Engineering College of EngineeringPeking University Department of Civil Engineering University of Hong Kong

Incremental algorithm is one of the most popular procedures for constructing Delaunay triangulations （DTs）. However, the point insertion sequence has a great impact on the amount of work needed for the construction of DTs. It affects the time for both point location and structure update, and hence the overall computational time of the triangulation algorithm. In this paper, a simple deterministic insertion sequence is proposed based on the breadth-first-search on a Kd-tree with some minor modifications for better performance. Using parent nodes as search-hints, the proposed insertion sequence proves to be faster and more stable than the Hilbert curve order and biased randomized insertion order （BRIO）, especially for non-uniform point distributions over a wide range of benchmark examples.

关键词： Incremental Delaunay triangulation algorithms Insertion sequences Kd-tree

A review of ferroelectric materials for high power devices

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Journal of Materiomics 2022年第4期8卷 739-752页

作者： sergey I.shkuratov Christopher s.Lynch Loki Incorporated 1334 Royal RoadNorwoodMO65717USA Bourns College of Engineering University of California at RiversideCA92521USA

Compact autonomous ultrahigh power density energy storage and power generation devices that exploitthe spontaneous polarization of ferroelectric materials are capable of producing hundreds of kilovoltvoltages,multi-kiloampere currents,and megawatt power levels for brief interval of *** storagelife of these devices is four orders of magnitude longer than that for electrochemical batteries andelectrochemical *** is an up to date survey of ferroelectric materials used for these highpower *** types of ferroelectric ceramics possess the ability to be depolarized under adia-batic compression and can be successfully used for high power *** addition to bulk ferro-electric ceramics,multilayer ferroelectric films are very efficient materials for high power *** importance is the ability of relaxor ferroelectric single crystals to produce significantly higherelectric charge density and energy density than ceramics,making them promising materials for highpower *** provided is a brief survey of recent developments of ferroelectric materials forhigh energy density and power density dielectric *** ceramics have been developed,including antiferroelectric and relaxor antiferroelectric solid solutions,providing high energy densityand efficiency simultaneously.

关键词： Energy storage Ferroelectric Antiferroelectric Relaxor High power density

JOINT INVEsTIGATION OF ROTATING FLOW WITH VORTEX BREAKDOWN UsING CFD, VIsUALIZATION AND LDV

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Journal of Hydrodynamics 2005年第4期17卷 455-458页

作者： LIU Ying-zheng CHEN Han-ping KOYAMA Hide s. school of Mechanical and Power Engineering Shanghai Jiaotong University Shanghai 200030 China Department of Mechanical Engineering Tokyo Denki University Tokyo Japan

Vortex breakdown of the steady axisymmetic rotating flow in a confined cylindrical container with a rotating endwall was numerically and experimentally studied. High-quality precision-controlled turntable facilities were established at shanghai Jiaotong University and Tokyo Denki University independently. Collaborative investigations of vortex breakdown were carried out using CFD, Laser Doppler Velocimetry （LDV） and streakline visualization, respectively. The characteristics of vortex breakdown were delineated in terms of comparative investigation using numerical and experimental results. sIMPLEC scheme and FMG multigrid was applied to numerical simulation. Numerical simulation was extensively compared with streakline visualization and LDV measurements, showing qualitative and quantitative agreements.

关键词： vortex breakdown CFD visualization Laser Doppler Velocimetry (LDV)

Efficient WENO-Based Prolongation strategies for Divergence-Preserving Vector Fields

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Communications on Applied Mathematics and Computation 2023年第1期5卷 428-484页

作者： Dinshaw s.Balsara saurav samantaray sethupathy subramanian Department of Physics University of Notre DameNotre DameINUSA Department of ACMs University of Notre DameNotre DameINUSA

Adaptive mesh refinement(AMR)is the art of solving PDEs on a mesh hierarchy with increasing mesh refinement at each level of the *** treatment on AMR hierarchies requires accurate prolongation of the solution from a coarse mesh to a newly defined finer *** scalar variables,suitably high-order finite volume WENO methods can carry out such a ***,classes of PDEs,such as computational electrodynamics(CED)and magnetohydrodynamics(MHD),require that vector fields preserve a divergence *** primal variables in such schemes consist of normal components of the vector field that are collocated at the faces of the *** a result,the reconstruction and prolongation strategies for divergence constraint-preserving vector fields are necessarily more *** this paper we present a fourth-order divergence constraint-preserving prolongation strategy that is analytically *** to higher orders using analytically exact methods is very *** overcome that challenge,a novel WENO-like reconstruction strategy is invented that matches the moments of the vector field in the faces,where the vector field components are *** approach is almost divergence constraint-preserving,therefore,we call it *** make it exactly divergence constraint-preserving,a touch-up procedure is developed that is based on a constrained least squares(CLsQ)method for restoring the divergence constraint up to machine *** the touch-up,it is called *** is shown that refinement ratios of two and higher can be *** item of broader interest in this work is that we have also been able to invent very efficient finite volume WENO methods,where the coefficients are very easily obtained and the multidimensional smoothness indicators can be expressed as perfect *** demonstrate that the divergence constraint-preserving strategy works at several high orders for divergence-free vector fields as well as vecto

关键词： PDEs Numerical schemes Mimetic

some Dielectric Properties of some Resin Varnishes

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Journal of Materials science & Technology 1995年第2期11卷 119-121页

作者： s.A.El-Henawii(Faculty of science, Helwan University, Cairo, Egypt) Heiwan Univ Cairo Egypt

The dielectric constant, the dielectric loss and the power factor of three types of resins namely polyesteramide, alkyd polyesteramide and alkyd resins were measured with in the frequency range of 105 to 107 Hz and the temperature range of 20 to 50℃. The activation energy of dielectric relaxation and the entropy changes were also calculated using the usual rate equation. The results obtained are recorded and discussed.

关键词： some Dielectric Properties of some Resin Varnishes RT

CuPc based organic-inorganic hetero-junction with Au electrodes

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Journal of semiconductors 2010年第7期31卷 22-25页

作者： Zubair Ahmad Muhammad H.sayyad Kh.s.Karimov Ghulam Ishaq Khan Institute of Engineering sciences and Technology TopiNWFP23460Pakistan Department of Mechanical Engineering 20 Symond Street AucklandUniversity of AucklandNew Zealand

A hetero-junction of n-silicon（n-si） and copper phthalocyanine（CuPc） has been *** current -voltage characteristics were investigated to explain the rectification and conduction *** effect of temperature and humidity on the electrical properties of n-si/CuPc hetero-junction has also been *** characteristics of the junction have been observed to be temperature and humidity dependent,so it is suggested that this junction can be used as a temperature and humidity sensor.

关键词： inorganic-organic hetero-junction n-si CuPc

Magnetic Behaviour of sm2Co7/Fe/sm2 Co7, Nanocomposite Trilayers with Cr and Ti Additions

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Chinese Physics Letters 2009年第3期26卷 255-257页

作者： F. shahzad s. A. siddiqi J. Zhou Advaaced Light source Berkeley Lab University of California Berkeley CA 94720 USA Centre for solid state Physics University of the Punjab Lahore-54590 Pakistan Department of Physics University of California Berkeley California 94720 USA

Trilayered sm2Co7/Fe/sm2Co7 spring exchange magnets are fabricated by dc magnetron sputtering on MgO substrates. Very thin layers （0.3-0.7 nm） of Cr and Ti are added at the interfaces of the two magnetic phases. The thickness of stucCo7 is kept at 20nm and Fe at 6nm while the thickness of Cr and Ti are varied as 0.3, 0.5, and 0.7nm. The base pressure of sputtering chamber is kept below 10^-7 Torr and Ar pressure at 3-8m Torr. The samples are characterized by x-ray diffraction （XRD） and sQUID magnetometer. We report improvement in exchange coupling of nonacomposite magnets by addition of thin layers of Cr at interfaces.

关键词： No English Keywords

Production of neutron-rich exotic nuclei in projectile fragmentation at Fermi energies

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Nuclear science and Techniques 2017年第2期28卷 18-23页

作者： R.Ogul N.Buyukcizmeci A.Ergun A.s.Botvina Department of Physics University of Selcuk ITP and Frankfurt Institute for Advanced studies J.W.Goethe University Institute for Nuclear Research Russian Academy of Sciences

Isotopic fragment yields of projectile fragmentation in peripheral collisions of^(86)Kr on^(124;112)sn and the mean neutron-to-proton ratios of the fragments are calculated, theoretically, within the ensemble approach of statistical multifragmentation model. Obtained data are compared to the experimental cross-section measurements for the projectile-like fragmentation in the reaction of 25 Me V/nucleon^(86)Kr+^(124;112)sn at Texas A&M *** show the enhancement in the production of neutronrich isotopes close to the projectile as observed in the experiments. We also demonstrate the universality of the limitation of the excitation energy induced in the projectile residues.

关键词： Projectile fragmentation Peripheral collisions Isotope productions Universality