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941.
周期系数的高维Riccati方程的周期解 总被引:2,自引:0,他引:2
本文研究了周期系数的高维Riccati方程X’=X·A(t)·X+B(t)·X+C(t),其中X∈R(n×1)A(t)∈R(1×n),B(t)∈R(n×n),C(t)E∈R(n×1);A(t),B(t),C(t)均是以2π为周期的实连续矩阵或向量函数,建立了该方程存在广义周期解的一个充要条件和存在周期解的两个充分条件,推广了周期系数的Riccati方程存在周期解的一些结论. 相似文献
942.
广义n阶Euler-Bernoulli多项式 总被引:23,自引:2,他引:23
刘国栋 《数学的实践与认识》1999,29(3):5-10
本文得到了广义n阶Euler数和广义n阶Bernoulli数,广义n阶Euler多项式和广义n阶Bernoulli多项式的关系式。 相似文献
943.
广义对角占优阵的一个等价条件 总被引:2,自引:0,他引:2
郑秉文 《纯粹数学与应用数学》1999,15(2):37-41
给出了实方阵为广义对角占优阵的充要条件,同时给出了判断广义对角占优阵可靠,可行,较简单方法。 相似文献
944.
This paper presents a meshless method for the nonlinear generalized regularized long wave(GRLW) equation based on the moving least-squares approximation.The nonlinear discrete scheme of the GRLW equation is obtained and is solved using the iteration method.A theorem on the convergence of the iterative process is presented and proved using theorems of the infinity norm.Compared with numerical methods based on mesh,the meshless method for the GRLW equation only requires the scattered nodes instead of meshing the domain of the problem.Some examples,such as the propagation of single soliton and the interaction of two solitary waves,are given to show the effectiveness of the meshless method. 相似文献
945.
In this paper, the generalized Darboux transformation is constructed to variable coefficient nonlinear Schrödinger (NLS) equation. The N-th order rogue wave solution of this variable coefficient NLS equation is obtained by determinant expression form. In particular, we present rogue waves from first to third-order through some figures and analyze their dynamics. 相似文献
946.
In this paper, the form invariance and the Lie symmetry of Lagrange's equations for nonconservative system in generalized classical mechanics under the infinitesimal transformations of group are studied, and the Noether's conserved quantity, the new form conserved quantity, and the Hojman's conserved quantity of system are derived from them. Finally, an example is given to illustrate the application of the result. 相似文献
947.
ZHAO Hui WANG Zhi-Xi 《理论物理通讯》2007,47(1):45-48
We investigate the entanglement of formation for a class of high-dimensional quantum mixed states. We present a kind of generalized concurrence for a class of high-dimensional quantum pure states such that the entanglement of formation is a monotonically increasing convex function of the generallzed concurrence, from the monotonicity and convexity the entanglement of formafion for a class of high-dimensional mixed states has been calculated analytically, 相似文献
948.
Tiziana Parasassi Ewa K. Krasnowska Luis Bagatolli Enrico Gratton 《Journal of fluorescence》1998,8(4):365-373
The steady-state and dynamic fluorescence spectral properties of 2-dimethylamino-6-lauroylnaphthalene (LAURDAN) and several other naphthalene derivatives are summarized to illustrate their sensitivity to the polarity of the environment. Results obtained both in solvents of different polarity and in phospholipid vesicles in two phase states are presented. The emission red shift observed in polar solvents and in the phospholipid liquid–crystalline phase is explained on the basis of dipolar relaxation of solvent molecules surrounding the fluorescent naphthalene moiety of these probes. In phospholipid environments, experimental evidence is shown that excludes the intramolecular relative reorientation of the dimethylamino and carbonyl groups in the naphthalene and the reorientation of the entire fluorescent moiety. The solvent dipolar relaxation observed for LAURDAN and PRODAN in phospholipid bilayers has been attributed to a small number of water molecules present at the membrane interface. A comparison between LAURDAN emission in phospholipid vesicles prepared in D2O and in H2O is also presented. The definition and the derivation of the generalized polarization function are also discussed. 相似文献
949.
Non-Maxwellian particle distribution functions possessing high energy tail
and shoulder in the profile of distribution function considerably change the damping characteristics of the waves. In the present paper Landau damping of electron plasma (Langmuir) waves and ion-acoustic waves in a hot, isotropic, unmagnetized plasma is studied with the generalized
(r,q) distribution function. The results show that for the Langmuir
oscillations Landau damping becomes severe as the spectral index r or q
reduces. However, for the ion-acoustic waves Landau damping is more
sensitive to the ion temperature than the spectral indices. 相似文献
950.