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991.
This paper reports a detailed numerical study of soliton switching in a high as well as low birefringent nonlinear coupler. It is shown that by controlling the polarization angle one can have nearly 100% transmission with excellent switching characteristics. It is shown that soliton remains stable during its propagation inside the coupler. However it is observed that high birefringent coupler exhibits relatively better soliton stability. We show that the coupler could be used as a soliton switch even at an input peak power less than the critical power, the power at which 50-50 power sharing takes place between the two cores, just by a judicious choice of the polarization angle.  相似文献   
992.
In this study, we use the addition theorem and superposition technique to solve the scattering problem with multiple circular cylinders arising from point sound sources. Using the superposition technique, the problem can be decomposed into two individual parts. One is the free‐space fundamental solution. The other is a typical boundary value problem (BVP) with specified boundary conditions derived from the addition theorem by translating the fundamental solution. Following the success of null‐field boundary integral formulation to solve the typical BVP of the Helmholtz equation with Fourier densities, the second‐part solution is easily obtained after collocating the observation point exactly on the real boundary and matching the boundary condition. The total solution is obtained by superimposing the two parts which are the fundamental solution and the semianalytical solution of the Helmholtz problem. An example was demonstrated to validate the present approach. The parameter study of size and spacing between cylinders are addressed. The results are well compared with the available theoretical solutions and experimental data. © 2011 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 2011  相似文献   
993.
The Unit Vector Method (UVM) is an orbit determination method extensively applied. In this paper, the UVM and classical Differential Orbit Improvement (DOI) are compared, and a fusion method is given for the orbit determination with different kind data. Based on non-orthogonal decomposition of position and velocity vectors, an approximation scheme is constructed to calculate the state transition matrix. This method simplifies the calculation of the approximate state transition matrix, analyzes the convergen...  相似文献   
994.
A general Fatou Lemma is established for a sequence of Gelfand integrable functions from a vector Loeb space to the dual of a separable Banach space or, with a weaker assumption on the sequence, a Banach lattice. A corollary sharpens previous results in the finite-dimensional setting even for the case of scalar measures. Counterexamples are presented to show that the results obtained here are sharp in various aspects. Applications include systematic generalizations of the distribution of correspondences from the case of scalar Loeb spaces to the case of vector Loeb spaces and a proof of the existence of a pure strategy equilibrium in games with private and public information and with compact metric action spaces.  相似文献   
995.
The aim of this paper is to extend the so-called perturbation approach in order to deal with conjugate duality for constrained vector optimization problems. To this end we use two conjugacy notions introduced in the past in the literature in the framework of set-valued optimization. As a particular case we consider a vector variational inequality which we rewrite in the form of a vector optimization problem. The conjugate vector duals introduced in the first part allow us to introduce new gap functions for the vector variational inequality. The properties in the definition of the gap functions are verified by using the weak and strong duality theorems.  相似文献   
996.
由分段三次参数多项式曲线拼合成的C1插值曲线的形状与数据点处的切矢有很大关系.基于对保形插值曲线特点的分析,本文提出了估计数据点处切矢的一种方法:采用使构造的插值曲线的长度尽可能短的思想估计数据点处的切矢,并且通过四组有代表性的数据对本方法和已有的三种方法进行了比较.  相似文献   
997.
第Ⅰ类两态叠加多模叠加态光场的非线性高阶压缩特性研究   总被引:101,自引:40,他引:61  
本文在文献20的基础上进一步提出了多模辐射场的N-Y最小测不准态、N-H最小测不准态、N-Y压缩最小测不准态以及N-H压缩最小测不准态等的定义.构造了由多模(q模)相干态|{Zj}>q及其相反态|{-Zj}>q的线性叠加所组成的第Ⅰ类两态叠加多模叠加态光场|ψ(2)1>q,利用文献20新近提出的有关多模辐射场的两种非线性高阶压缩的定义,首次对态|ψ(2)1>q的N次方Y压缩及N次方H压缩效应进行了详细研究.结果表明,1)当N为偶数时,态|ψ(2)1>q恒处于N-Y最小测不准态;当N为奇数时,态|ψ(2)1>q在一定条件下可呈现出周期性变化的、任意阶的N次方Y压缩效应.2)当q·N为偶数时,态|ψ(2)1>q恒处于N-H最小测不准态;当q·N为奇数时,在另外的条件下,态|ψ(2)1>q则可呈现出周期性变化的、任意阶的N次方H压缩效应.3)N次方Y压缩及N次方H压缩效应的压缩深度与腔模总数q、压缩参数Rj以及压缩阶数N等非线性相关,后者与上述参量的非线性关联程度要比前者的更强.  相似文献   
998.
Some existence results for vector quasivariational inequalities with multifunctions in Banach spaces are derived by employing the KKM-Fan theorem. In particular, we generalize a result by Lin, Yang and Yao, and avoid monotonicity assumptions. We also consider a new quasivariational inequality problem and propose notions of weak and strong equilibria while applying the results to traffic network problems.  相似文献   
999.
本文引入向量水平函数和向量水平集的概念。这两个概念的意义在于:(1)利用向量水平集的性质推断单调系统的路集性质;(2)利用向量水平集的性质判断多态系统是否关联;(3)利用向量水平集的性质可心简化多态单调关联系统模型类的分析,本文先给出一般性结果,然后分析了二部件三态系统。  相似文献   
1000.
In this note, we provide general sufficient conditions under which, if F is a compact [resp. w*-compact] subset of the topological dual Y* of a nonreflexive normed space Y partially ordered by a closed convex pointed cone K, then the set of points in F that can be supported by strictly positive elements in the canonical embedding of Y in Y** is norm dense [resp. w*-dense] in the efficient [maximal] point set of F. This result gives an affirmative answer to the conjecture proposed by Gallagher (Ref. 19), and also generalizes the results stated in Ref. 19 and some space specific results given in Refs. 17, 18, and 11.  相似文献   
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