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排序方式: 共有229条查询结果,搜索用时 281 毫秒
71.
利用与分数次积分相关的Olsen型不等式,我们得到了薛定谔型椭圆方程的内部Morrey估计, 其中位势函数满足反H\"older条件.  相似文献   
72.
A potential reduction algorithm is proposed for optimization of a convex function subject to linear constraints. At each step of the algorithm,a system of linear equations is solved toget a search direction and the Armijo‘s rule is used to determine a stepsize. It is proved that thealgorithm is globally convergent. Computational results are reported.  相似文献   
73.
We discuss the effect of nonlinearity on the scattering dynamics of solitary waves. The pure nth power model with the interaction potential V (Х) = Х^n/n is present, which is a paradigm model in the study of solitary waves. The dependence of the scattering property on nonlinearity is closely related to the topological structures of the solitary waves. Moreover, for one of the four collision types, the rates of energy loss increase with the strength of nonlinearity and would reach 1 at n ≥ 10, which means that the two solitary waves would become of fragments completely after the collision.  相似文献   
74.
杨俊  沈尧天 《应用数学》2006,19(1):110-119
讨论一个含临界位势的广义平均曲率方程在Dirichlet边界条件下解的存在性.此方程相应的变分泛函关于u的梯度非齐次,且Sobolev空间嵌入失去紧性.为了克服这些困难,本文将关于范数的一个基本结论推广到一般的偶泛函,并利用C.K.N不等式及Ambrosetti的山路引理证明了方程存在非平凡解.  相似文献   
75.
A theoretical model is established to simulate the penetration process of C20 clusters in oxides (Al2O3, SiO2) at different incident velocities. The induced spatial potential by the incident clusters is described by the dielectric response formalism, in which the Mermin-type dielectric function is adopted to provide a realistic evaluation of the electronic properties of the oxides. The charge distribution of individual ions is derived by using the Brandt-Kitagawa effective charge model, also under the consideration of the asymmetric influence from the wake potential. The stopping power of the clusters and the Coulomb explosion processes are derived by solving the motion equation of the individual ions, when taking into account the multiple scattering effect simulated by using the Monte Carlo method. It is found that the dynamical interaction potential between ions leads to a spatial asymmetry to the cluster structure and the charge distribution for high velocity clusters, and will not be in effect as the incident velocities decrease.  相似文献   
76.
白鸽  李家荣 《中国物理 C》1996,20(9):801-811
从QGP的动力论方程出发,计及运动检验夸克的色电场扰动,采用微扰方法,并在高温极限下得到QGP中夸克的分布函数和色电势.给出了考虑运动效应在内的德拜长度λD(或屏蔽质量ωD)与温度T的关系,在静态极限下它们与QCD理论相符.  相似文献   
77.
考虑R2中的含临界位势的非线性椭圆方程齐次Dirichlet问题. 通过建立一常数为最佳的含权不等式, 确定了临界位势, 并讨论了含临界位势的Laplace方程特征值问题. 通过建立含一个奇点的解的Pohozaev型恒等式并结合Cauchy-Kovalevskaya定理得到了含临界位势非线性椭圆型方程有奇点的解的不存在性结果. 此外, 利用山路定理和特征值的性质得到了这一问题多重解的存在性的一系列结果.  相似文献   
78.
本文考虑二阶Hamilton系统其中对T>0,为一平均值为零之T周期函数,对常数β>2和α>0,V有形式α|x|~β+W(x),W满足某些增长性条件,则利用鞍点定理证明了此系统具有非平凡的T周期解.  相似文献   
79.
Numerical Solution for the Helmholtz Equation with Mixed Boundary Condition   总被引:1,自引:0,他引:1  
We consider the numerical solution for the Helmholtz equation in R~2 with mixed boundary conditions.The solvability of this mixed boundary value problem is estab- lished by the boundary integral equation method.Based on the Green formula,we express the solution in terms of the boundary data.The key to the numerical real- ization of this method is the computation of weakly singular integrals.Numerical performances show the validity and feasibility of our method.The numerical schemes proposed in this paper have been applied in the realization of probe method for inverse scattering problems.  相似文献   
80.
We investigate the ground-state properties of a two-dimensional two-electron quantum dot with a Gaussian confining potential under the influence of perpendicular homogeneous magnetic field. Calculations are carried out by using the method of numerical diagonalization of Hamiltonian matrix within the effective-mass approximation. A ground-state behaviour (singlet→triplet state transitions) as a function of the strength of a magnetic field has been found. It is found that the dot radius R of the Gaussian potential is important for the ground-state transition and the feature of ground-state for the Gaussian potential quantum dot (QD), and the parabolic potential QDs are similar when R is larger. The larger the quantum dot radius, the smaller the magnetic field for the singlet-triplet transition of the ground-state of two interacting electrons in the Gaussian quantum dot.  相似文献   
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