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991.
导体旋转椭球电学量的一种计算方法 总被引:8,自引:4,他引:4
用一种新方法,计算了孤立导体旋转椭球的面电荷密度、电容、电势和电场强度,并得出相应的解析表达式。 相似文献
992.
993.
S. Cafieri M. D’Apuzzo M. Marino A. Mucherino G. Toraldo 《Journal of Optimization Theory and Applications》2006,129(1):55-75
In this paper, we present an interior-point algorithm for large and sparse convex quadratic programming problems with bound
constraints. The algorithm is based on the potential reduction method and the use of iterative techniques to solve the linear
system arising at each iteration. The global convergence properties of the potential reduction method are reassessed in order
to take into account the inexact solution of the inner system. We describe the iterative solver, based on the conjugate gradient
method with a limited-memory incomplete Cholesky factorization as preconditioner. Furthermore, we discuss some adaptive strategies
for the fill-in and accuracy requirements that we use in solving the linear systems in order to avoid unnecessary inner iterations
when the iterates are far from the solution. Finally, we present the results of numerical experiments carried out to verify
the effectiveness of the proposed strategies. We consider randomly generated sparse problems without a special structure.
Also, we compare the proposed algorithm with the MOSEK solver.
Research partially supported by the MIUR FIRB Project RBNE01WBBB “Large-Scale Nonlinear Optimization.” 相似文献
994.
995.
996.
利用线性电位扫描光伏安法等技术研究钛基体上Se半导体薄膜的电化学形成及转化过程.实验结果表明,在H_2SeO_3溶液中进行电沉积可获得p型Se薄膜,它可在酸性CdSO_4溶液中阴极转化为n型CdSe.讨论了Se的电沉积动力学及其转化为CdSe的可能机理.所述原理可望用于p-n异质结的电化学制备. 相似文献
997.
若干二维问题的WKB近似能级 总被引:2,自引:0,他引:2
讨论了二维空间的WKB近似方法,导出了Bohr-Sommerfeld量子化条件,并计算了若干具体问题的能级,包括中心势情况和Aharonov-Bohm势加中心势情况。 相似文献
998.
Teik-Cheng Lim 《Journal of mathematical chemistry》2007,42(1):93-101
This paper tests the validity of a Lennard–Jones-type and Morse-type potential functions, consisting a combination of pi and
golden ratio constants, for describing intermolecular and interatomic interaction energy. The adjustable parameter, n, can be obtained based on experimental data near the minimum well-depth or by parametric conversion from other established
potential functions. The remarkably good correlation of the proposed potential functions with experimental data and other
potential functions reveal an intriguing property of the relationship between pi and golden ratio within the context of chemistry. 相似文献
999.
B. G. Vakulov 《Mathematical Notes》2006,80(5-6):645-657
In this paper, we study the images of operators of the type of spherical potential of complex order and of spherical convolutions with kernels depending on the inner product and having a spherical harmonic multiplier with a given asymptotics at infinity. Using theorems on the action of these operators in Hölder-variable spaces, we construct isomorphisms of these spaces. In Hölder spaces of variable order, we study the action of spherical potentials with singularities at the poles of the sphere. Using stereographic projection, we obtain similar isomorphisms of Hö lder-variable spaces with respect to n-dimensional Euclidean space (in the case of its one-point compactification) with some power weights. 相似文献
1000.
Ching-Chuan Su 《Foundations of Physics Letters》2006,19(2):187-194
It is known that for the magnetic force due to a closed circuit, the Weber force law can be identical to the Lorentz force
law. In this investigation it is shown that for both the electric and the magnetic force of the quasi-static case, the Riemann
force law can be identical to the Lorentz force law, while the former is based on a potential energy depending on a relative
speed and is in accord with Newton's law of action and reaction. 相似文献