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941.
942.
绕组故障时异步电机定子电磁振动频谱的计算 总被引:1,自引:1,他引:0
丁梵林 《西安交通大学学报》1990,24(2):111-119
本文阐述在绕组故障和非故障情况下异步电机定子径向电磁振动频谱的计算方法,这一方法可以全面考虑各种气隙磁场谐波的影响,并对一台绕线式异步电机在定子绕组发生相间短路及正常运行时定子电磁振动的频谱作了计算和比较. 相似文献
943.
944.
Marian Bocea 《Journal of Mathematical Analysis and Applications》2008,342(1):485-496
In the framework of Nonlinear Elasticity, the asymptotic behavior of the free energy of a martensitic material is studied as the height of the sample tends to zero. The effective thin film energy is identified in terms of parametrized probability measures, which allows for a justification of the kinematic compatibility conditions proposed in Bhattacharya and James' theory of thin films of martensitic materials, in the absence of higher order interfacial energy contributions to the three-dimensional bulk energy. 相似文献
945.
In this paper, we propose a GL method for solving the ordinary and the partial differential equation in mathematical physics and chemics and engineering. These equations govern the acustic, heat, electromagnetic, elastic, plastic, flow, and quantum etc. macro and micro wave field in time domain and frequency domain. The space domain of the differential equation is infinite domain which includes a finite inhomogeneous domain. The inhomogeneous domain is divided into finite sub domains. We present the solution of the differential equation as an explicit recursive sum of the integrals in the inhomogeneous sub domains. Actualy, we propose an explicit representation of the inhomogeneous parameter nonlinear inversion. The analytical solution of the equation in the infinite homogeneous domain is called as an initial global field. The global field is updated by local scattering field successively subdomaln by subdomain. Once all subdomains are scattered and the updating process is finished in all the sub domains, the solution of the equation is obtained. We call our method as Global and Local field method, in short , GL method. It is different from FEM method, the GL method directly assemble inverse matrix and gets solution. There is no big matrix equation needs to solve in the GL method. There is no needed artificial boundary and no absorption boundary condition for infinite domain in the GL method. We proved several theorems on relationships between the field solution and Green's function that is the theoretical base of our GL method. The numerical discretization of the GL method is presented. We proved that the numerical solution of the GL method convergence to the exact solution when the size of the sub domain is going to zero. The error estimation of the GL method for solving wave equation is presented. The simulations show that the GL method is accurate, fast, and stable for solving elliptic, parabolic, and hyperbolic equations. The GL method has advantages and wide applications in the 3D electromagnetic (EM) 相似文献
946.
Quantum controlled phase gate and cluster states
generation via two superconducting quantum interference devices in a
cavity 总被引:3,自引:0,他引:3
Z.-Y. Xue G. Zhang P. Dong Y.-M. Yi Z.-L. Cao 《The European Physical Journal B - Condensed Matter and Complex Systems》2006,52(3):333-336
A scheme for implementing 2-qubit quantum controlled phase gate (QCPG) is proposed with two superconducting quantum interference
devices (SQUIDs) in a cavity. The gate operations are
realized within the two lower flux states of the SQUIDs by using a quantized cavity field and classical microwave pulses.
Our scheme is achieved without any type of measurement, does not use the cavity mode as the data bus and only requires a very
short resonant interaction of the SQUID-cavity system. As an application of the QCPG operation, we also propose a scheme for
generating the cluster
states of many SQUIDs. 相似文献
947.
S. Hudlet M. Saint Jean C. Guthmann J. Berger 《The European Physical Journal B - Condensed Matter and Complex Systems》1998,2(1):5-10
We propose a very simple method to determine the electrical tip-surface force in Atomic Force Microscopes used to study the
electrical properties of metallic or insulating materials; the analysis of the measurements as well as determination of the
appropriate experimental procedures requiring an analytical model of the tip-surface capacitance. The comparison of force
expressions obtained by this method with those obtained by exact derivation in the case of the sphere-infinite plane system
shows very good agreement. This method is then applied to determine the tip-surface force, the real shape of the tip being
introduced in the derivation. The obtained expression is compared to experimental and numerical data. We emphasize that this
method is very general and can be applied to any axially symmetric capacitor.
Received: 17 June 1997 / Received: 16 September 1997 / Accepted: 7 November 1997 相似文献
948.
Chitin–cellulose blends dissolved in dimethylacetamide containing LiCl (7% w/w) have been studied in a wide concentration range, from very dilute solutions to medium concentrations and up to solid films (absence of diluent). The intrinsic viscosities at various chitin–cellulose ratios, as well as the phase diagram behavior, imply a good compatibility between the components. The result is confirmed by the infrared measurements on solid films. The lack of anisotropic phase formation in chitin–diluent binary solutions and the anomalous trend of v′CH–CE line on the phase diagram are both interpreted on the basis of aggregation phenomena. 相似文献
949.
在Dirac工作的基础上对电磁场作了更进一步的分解───电磁场按光子对应分解。这一分解的成功找到了经典电磁场与量子电磁场的一种基元对应关系,进而,揭示出电磁场在量子化之前就具有结构上的颗粒性。 相似文献
950.
天线在随机脉动压力作用下的运动感应电磁噪声 总被引:2,自引:0,他引:2
研究了天线在随机脉动压力作用下的运动感应电磁噪声,包括:随机脉动压力谱密度计算公式的建立;电极对天线运动感应电磁噪声的产生机理与计算方法;仿真结果及分析。研究结果对于水下通信有重要的应用意义。 相似文献