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81.
Cansu Betin 《代数通讯》2013,41(6):1901-1907
We consider a ring whose left modules of finite length are semisimple and prove some results on such a ring. We also consider when such a ring is a left V-ring.  相似文献   
82.
In this paper, we present a measure of distance in a second-order cone based on a class of continuously differentiable strictly convex functions on ℝ++. Since the distance function has some favorable properties similar to those of the D-function (Censor and Zenios in J. Optim. Theory Appl. 73:451–464 [1992]), we refer to it as a quasi D-function. Then, a proximal-like algorithm using the quasi D-function is proposed and applied to the second-cone programming problem, which is to minimize a closed proper convex function with general second-order cone constraints. Like the proximal point algorithm using the D-function (Censor and Zenios in J. Optim. Theory Appl. 73:451–464 [1992]; Chen and Teboulle in SIAM J. Optim. 3:538–543 [1993]), under some mild assumptions we establish the global convergence of the algorithm expressed in terms of function values; we show that the sequence generated by the proposed algorithm is bounded and that every accumulation point is a solution to the considered problem. Research of Shaohua Pan was partially supported by the Doctoral Starting-up Foundation (B13B6050640) of GuangDong Province. Jein-Shan Chen is a member of the Mathematics Division, National Center for Theoretical Sciences, Taipei Office. The author’s work was partially supported by National Science Council of Taiwan.  相似文献   
83.
In this work, a partial differential equation, which has several important applications, is investigated, and some techniques based on semianalytic (or quasi‐numerical) approaches are developed to find its solution. In this article, the homotopy perturbation method (HPM), Adomian decomposition method, and the modified homotopy perturbation method are proposed to solve the Eikonal equation. HPM yields solution in convergent series form with easily computable terms, and in some case, yields exact solutions in one iteration. In other hand, in Adomian decomposition method, the approximate solution is considered as an infinite series usually converges to the accurate solution. Moreover, these methods do not require any discretization, linearization, or small perturbation, and therefore reduce the numerical computation a lot. Several test problems are given and results are compared with the variational iteration method. © 2009 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2010  相似文献   
84.
The invariant Hermitian lattices in the Steinberg module of SL2(q) are described. These lattices are connected with generalized quadratic residue codes over a field of four elements. The isometry groups of in-variant lattices are calculated. In particular, lbdimensional unimodular lattices over Eisenstein numbers with minimum norm 3 and automor- phism group Z6x PSp6(3) are obtained.  相似文献   
85.
单位圆内拟亚纯映射的奇异点   总被引:1,自引:0,他引:1  
本文通过一般化Tsuji的一个结果,证明了单位圆内零级K-拟亚纯映射涉及重值的一类奇异点的存在性.  相似文献   
86.
We present a model and an associated numerical scheme to simulate complex electrokinetic processes in channels with nonuniform cross‐sectional area. We develop a quasi‐1D model based on local cross‐sectional area averaging of the equations describing unsteady, multispecies, electromigration‐diffusion transport. Our approach uses techniques of lubrication theory to approximate electrokinetic flows in channels with arbitrary variations in cross‐section; and we include chemical equilibrium calculations for weak electrolytes, Taylor–Aris type dispersion due of nonuniform bulk flow, and the effects of ionic strength on species mobility and on acid–base equilibrium constants. To solve the quasi‐1D governing equations, we provide a dissipative finite volume scheme that adds numerical dissipation at selective locations to ensure both unconditional stability and high accuracy. We couple the numerical scheme with a novel adaptive grid refinement algorithm that further improves the accuracy of simulations by minimizing numerical dissipation. We benchmark our numerical scheme with existing numerical schemes by simulating nonlinear electrokinetic problems, including ITP and electromigration dispersion in CZE. Simulation results show that our approach yields fast, stable, and high‐resolution solutions using an order of magnitude less grid points compared to the existing dissipative schemes. To highlight our model's capabilities, we demonstrate simulations that predict increase in detection sensitivity of ITP in converging cross‐sectional area channels. We also show that our simulations of ITP in variable cross‐sectional area channels have very good quantitative agreement with published experimental data.  相似文献   
87.
An experimental investigation of quasireversible maximum (QRM) of azobenzene on mercury electrode by two methods, i.e., traditional square‐wave voltammetry (SWV) and fast Fourier transformed square‐wave voltammetry (FT‐SWV), was presented, and the influence factors on QRM of FT‐SWV were discussed. The results show that the rate constants derived from FT‐SWV agree with that of derived from traditional SWV with acceptable differences, showing a sound verification that the rate constants derived from FT‐SWV were reliable. In addition, some theoretical predictions on FT‐SWV were experimentally confirmed through the characterization of strongly adsorbed azobenzene on mercury film electrode. As a result, FT‐SWV is further proved to be a powerful technique in kinetic studies of the surface adsorbed processes.  相似文献   
88.
正规几乎PP环   总被引:2,自引:0,他引:2  
陈兰清 《数学研究》1998,31(2):221-224
首先探讨正规几乎PP环的内刻划及左右对称性;其次,研究正规几乎PP环与PP环的关系,最后证明多项式环R[X」是正规几乎PP环当且仅当R是正规几乎PP环.  相似文献   
89.
In this paper, we consider the set-valued vector optimization problems with constraint in locally convex spaces. We present the necessary and sufficient conditions for Henig efficient solution pair, globally proper efficient solution pair and super efficient solution pair without the ordering cones having the nonempty interior.  相似文献   
90.
The Quasi-phase-matching periodically poled flux-grown KTP by high electrical field method is researched. A 8×5×1mm3, Λ=9.0μm PPKTP wafer is successfully fabricated for the first order QPM SHG. The interactive length of the sample is about 3mm. The SHG scheme of Nd:YAG at 1064nm tested that the output power of cw 532nm green light is 0.2mw at room temperature with fundamental power of 1.2w. The normalized conversion efficiency is about 0.09% (W·cm)-1.  相似文献   
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