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ON SOLVAbILITY OF A bOUNDARY VALUE PRObLEM FOR THE POISSON EQUATION WITH A NONLOCAL bOUNDARY OPERATOR

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Acta Mathematica Scientia 2015年第5期35卷 970-980页

作者： b.j.KADIRKULOV M.KIRANE Tashkent State Institute for Oriental Studies Laboratoire de Mathématiques Image et Applications Université de La Rochelle NAAM Research Group Department of Mathematics Faculty of ScienceKing Abdulaziz University

In this work, we investigate the solvability of the boundary value problem for the Poisson equation, involving a generalized Riemann-Liouville and the Caputo derivative of fractional order in the class of smooth functions. The considered problems are generalization of the known Dirichlet and Neumann oroblems with operators of a fractional order.

关键词： operator of fractional integration and differentiation solvability boundary value problem Riemann-Liouville operator Caputo fractional derivative Poisson equation Dirichlet and Neumann problems

STAbILITY AND RESONANCES OF MULTISTEP COSINE METHODS

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journal of Computational Mathematics 2012年第5期30卷 517-532页

作者： b. Cano M.j. Moreta Departamento de Matemdtica Aplicada IMUVA. Facultad de Ciencias. Paseo Belen 7 CP 47011 Valladolid Spain Departamento de Fundamentos del Andlisis Econdmico I. Universidad Complutense de Madrid. Campus de Somosaguas Pozuelo de Alarcdn 28223 Madrid Spain

In a previous paper, some particular multistep cosine methods were constructed which proved to be very efficient because of being able to integrate in a stable and explicit way linearly stiff problems of second-order in time. In the present paper, the conditions which guarantee stability for general methods of this type are given, as well as a thorough study of resonances and filtering for symmetric ones （which, in another paper, have been proved to behave very advantageously with respect to conservation of invariants in Hamiltonian wave equations）. What is given here is a systematic way to analyse and treat any of the methods of this type in the mentioned aspects.

关键词： Exponential integrators Multistep cosine methods Second-order partial dif-ferential equations Stability Resonances

Interfacial effects in electromagnetic coupling within piezoelectric phononic crystals

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Acta Mechanica Sinica 2009年第1期25卷 95-99页

作者： F. j. Sabina A.b.Movchan Instituto de Investigaciones en Matematicas Aplicadas yen Sistemas Universidad Nacional Autónoma de México Department of Mathematical Sciences University of Liverpool

In this paper, we discuss waves in piezoelectric periodic composite, with the emphasis on the connection between the electromechanical coupling and the effects of dispersion of bloch-Floquet waves. A particular attention is given to structures containing interfaces between dissimilar media and localization of the electrical fields near such interfaces.

关键词： Piezoelectric periodic composites Interfaces Dispersion of bloch-Floquet waves

Approach for electrodynamic force for compensation in low voltage circuit breaker WP 630-1.2 type

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journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第3期8卷 393-396页

作者： LU Na XU L.j Miedzifiski b Automation School Beijing University of Posts and Telecommunications Beijing 100876 China Electrical Power Engineering Institute Wroclaw University of Technology Wroclaw Poland

Undesirable repulsive force between contact members due to both a current path shrink near a real contact area and/or so-called pinch effect is particularly onerous for power switch applications, and results in either contact floating or bouncing which are associated with an electric arc following contact welding. This problem is of great importance for any circuit breaker especially for compact low voltage vacuum circuit breakers. To avoid contact floating at closure and during any inrush current under short circuit conditions, the electrodynamic repulsive force can be employed successfully if we use a special compensation system flexibly combined with the contact itself. However to select and design the compensation system properly, its efficiency has to be known. This paper presents an approach to obtain the electrodynamic force value depending on different shaped (rectangular, square, circle and arch) copper plates used in the compensator by using ANSYS for current values 40 kA RMS. Curve-fitting was done according to the calculating results, the optimization designing of compensation unit is based on them.

关键词： Compensation. Electrodynamic force. FEM (Finite Element Method)

Hole burning in the Fock Space: from Single to Several Holes

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Chinese Physics Letters 2001年第11期18卷 1467-1469页

作者： b.baseia j.M.C.Malbouisson Instituto de Fisica Universidade Federal de Goias74001-970GoianiaGOBrazil Instituto de Fisica Universidade Federal da Bahia40210-340SalvadorBABrazil

In our previous papers we have studied the production of a single hole in the photon number distribution of a field state [Phys. Lett. A 240 (1998) 277;253 (1999) 123]. In this letter we extend the procedure for the c... 详细信息

关键词： letter creation distribution

Comparisons of electrical and optical properties between graphene and silicene A review

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Chinese Physics b 2018年第2期27卷 299-313页

作者： Wirth-Lima A j Silva M G Sombra A S b Laboratory of Telecommunications and Materials Science and Engineering-www.locem.ufc.br-Fortaleza CearaBrazil Department of Physics Science CenterFederal University of Ceara(U.F C.)-FortalezaCear4Brazil State University of Vale do Acarau SobralCeardBrasil

Two-dimensional （2D） metamaterials are considered to be of enormous relevance to the progress of all exact sciences. Since the discovery of graphene, researchers have increasingly investigated in depth the details of electrical/optical proper- ties pertinent to other 2D metamaterials, including those relating to the silicene. In this review are included the details and comparisons of the atomic structures, energy diagram bands, substrates, charge densities, charge mobilities, conductivities, absorptions, electrical permittivities, dispersion relations of the wave vectors, and supported electromagnetic modes related to graphene and silicene. Hence, this review can help readers to acquire, recover or increase the necessary technological basis for the development of more specific studies on graphene and silicene.

关键词： graphene silicene electrical/optical properties

Female waist-to-hip ratio,body mass index and sexual attractiveness in China

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Current Zoology 2010年第2期56卷 175-181页

作者： b.j. DIXSON baoguo LI A.E DIXSON School of biological Sciences Victoria University of Wellington P O Box 600 Wellington New Zealand College of Life Sciences and Key Laboratory Resource Biology and Biotechnology in Western China Ministry of Education Northwestern University Xi＇an China

Men and women at Northwest University （n=751）, Xi＇an, China were asked to judge the attractiveness of photographs of female patients who had undergone micrograft surgery to reduce their waist-to-hip ratios （WHR）. Micrograft surgery involves harvesting adipose tissue from the waist and reshaping the buttocks to produce a low WHR and an ‘hourglass＇ female figure. This gynoid distribution of female body fat has been shown to correlate with measures of fertility and health. Significantly larger numbers of subjects, of both sexes, chose post-operative photographs, with lower WHRs, as more attractive than pre-operative photographs of the same women. Some patients had gained, and some had lost weight, post-operatively, with resultant changes in body mass index （bMI）. However, these changes in bMI were not related to judgments of attractiveness. These results show that the hourglass female figure is rated as attractive in China, and that WHR, rather than bMI, plays a crucial role in such attractiveness judgments.

关键词： China Waist-to-hip ratio body mass index Female attractiveness Sexual selection

Effects of adenosine triphosphate concentration on motor force regulation during skeletal muscle contraction

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Acta Mechanica Sinica 2017年第2期33卷 243-249页

作者： j. Wei C. Dong b. Chen Department of Engineering Mechanics Zhejiang UniversityHangzhou 310058 China

We employ a mechanical model of sarcomere to quantitatively investigate how adenosine triphosphate (ATP) concentration affects motor force regulation during skeletal muscle contraction. Our simulation indicates that there can be negative cross-bridges resisting contraction within the sarcomere and higher ATP concentration would decrease the resistance force from negative cross-bridges by promoting their timely detachment. It is revealed that the motor force is well regulated only when ATP concentration is above a certain level. These predictions may provide insights into the role of ATP in regulating coordination among multiple motors.

关键词： Motor force regulation ATP Muscle contraction Myosin

Analysis of force and energy density transferred to barrier in a single degree of freedom vibro-impact system

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journal of Central South University 2017年第6期24卷 1351-1359页

作者： j.Marzbanrad M.Shahsavar b.beyranvand Vehicle Dynamical Systems Research Laboratory School of Automotive EngineeringIran University of Science and TechnologyTehyanNarmakIran

A mass-spring-damper linear oscillator with a limiting stop barrier is presented. Modeling non-smooth processes in mechanical engineering is a complex problem. It is especially for the systems with more than a single degree of freedom. but recent studies in dynamical systems have been applied to single degree of freedom systems. The vibrating system, consisting of an oscillator with amplitude of motion limited by a barrier, is known as a vibro-impact system. The amount of force and kinetic energy transferred to a barrier has an important application in designing of engineering systems that undergo the vibro-impact phenomenon. The results show the effect of changing restitution coefficient of a barrier on the amount of force and energy absorbed.

关键词： vibro-impact impact oscillator energy density restitution coefficient