查询词典 periodic distribution

Some conditions for weakly Persistence and extinction are obtained;In the second part, we respectively use C_h space and C_g space theorem to study the existence of periodic solutions of Lotka-Volterra equation with infinite delay, in the end we get the condition of the existense of periodic solutions and estimate the interzone of it.

第二部分利用相空间理论，分别以C_h空间和C_g空间为相空间研究了具有无限时滞的Lotka-Volterra方程周期解的存在性问题，给出了周期解存在的充分条件，并估计出了周期解的存在区间。

The property of translate invariant transformation in randomly-perturbed periodic structure is widely extended, owing to the demonstration of its origin from the spectral periodicity of the periodic structure.

4指出无序扰动周期结构中关于局域长度的平移等价变换是扰动前周期结构光谱周期性的结果，从而将该变换推广到所有厚度无序扰动的周期结构。

In the present work,the existence and uniqueness results aboutperiodic boundary value problems for different kinds of the nonlin-ear periodically perturbed nonconservative systems are establishedthrough the discretization technique,under suitable assumptions,by using global inverse function theorem and result about the ex-istence and uniqueness of periodic solution for nonhomogeneouslyfirst order linear periodic boundary value problem.

本文的第一章概述了在讨论原问题解的存在唯一性过程中以及构造和分析相关的数值求解方法时将要用到的全局反函数定理、有关矩阵特征值的若干重要引理、线性常微分方程非齐次周期问题解的存在唯一性定理和单参数影射方法及有关结论，并简单回顾了已有的证明非线性微分方程周期边值问题解的存在唯一性的方法，其中包括谱理论、最大最小化形式方法、摄动技术和全局反函数理论方法，最后，介绍了两类数值求解非线性微分方程问题的方法。

Consisting of the protracting graph of hydrogen-like atom"s angle distributing, computer simulation of the symmetry of molecular orbital and chemical reaction mechanism, showing the molecular point group and symmetry element, computer simulation of molecular vibration, Bravias"s crystal lattice and their transforming, extracting of plane periodic lattice, extracting of solid periodic lattice, close packing of isometrical pellet and the structure of simple mental substance, close packing of unequal pellet and crystal structure of representative ionic crystal, Computer Simulation of Phase Analysis by X-ray Diffraction.

内容包括类氢原子角度分布图的绘制，分子轨道对称性和反应机理的微机模拟，分子点群和对称元素显示，分子振动运动的微机模拟，布拉维晶格和晶格转化，平面点阵抽取，立体点阵抽取，等径网球的密堆积和金属单质结构，不等径圆球密堆积和典型离子晶体结构，X射线多晶衍射的微机模拟十个子模块。

This system is permanent by comparative principle and globally asymptotically stable through constructing a Liapunov function; for the periodic case, the research has obtained conditions for existence, uniqueness and stability of a positive periodic solution.

利用比较原理研究了系统的持久性，通过构造Liapunov函数证明了系统的全局渐近稳定性，在假设系统为周期系统的条件下得到了正周期解的存在唯一性和全局渐近稳定的充分条件。

Furthermore, when the system is a periodic system, sufficient conditions are obtained that guarantee the existence, uniqueness and global attractivity of the positive periodic solution by applying the Brouwer fixed theorem and the method of constructing Liapunov function.

利用比较原理给出了系统一致持久性的充分条件；当系统是周期系统时，应用Brouwer不动点原理和构造Liapunov函数的方法给出其存在惟一且全局吸引的ω-周期正解的充分条件，并通过实例验证了文中定理条件的可实现性。

Furthermore, Fourier-type periodic DOE is one of the most important kinds of DOEs. Therefore, based on scalar diffraction theory, this project will study the efficiency limit of static and dynamic Fourier-type periodic DOEs.

又傅氏周期性绕射光学元件为最重要的绕射光学元件种类之一，故本计画将依据纯量绕射理论，深入研究傅氏周期性绕射光学元件的绕射效率上限。

The second section: Under the conditions of nonlinear boundary controbility, we consider the initial boundary value problem of Camassa—Holm equations with dissipative. By using the contractive mapping fixed point theorem and a priori estimates, the existence of global smooth solution, global attractor in H〓, time periodic solution or almost-periodic solution and the global exponential stability are proved.

第二部分：在非线性控制边界条件之下，对于带耗散项的Camassa—Holm方程的初边值问题，用压缩映射不动点原理及先验估计方法，证明了整体光滑解的存在性、整体解的指数稳定性、H〓空间中整体吸引子的存在性以及时间周期解和殆时间周期解的存在性。

In the chapter 3,we base on the existence of periodic solution ,using the method of linearization and applying the mean value theorem and the variation-of-constants formula, we get the sufficient condition of the exponential stability of periodic solution of a class of nonlinear functional differential system .

在第三章中，建立在系统周期解存在的基础上，利用线性化的方法，根据微分中值定理和常量变差公式，得到了一类非线性泛函微分系统周期解指数稳定的充分条件。

Methods: Twenty-four Kkay mice were divided into three groups(n=8):diabetes group,methionine-diet group,folic acid and vitamin B12 treatment group. C57Bl/6 mice were used as controls(C57). Four months later,the mice were sacrificed and their serum levels of Hcy,folic acid and vitamin B12 were measured by fluorescence polarization immunoassay. Pathological changes in kidneys were examined with the periodic acid schiff method with periodic acid-silver methenamine staining under electron microscope. Expression of MMP-9 protein or mRNA was detected by RT-PCR with immunohistochemical staining. Results: Different morphological changes of DN were found in Kkay mice.

Kkay糖尿病鼠随机分3组：糖尿病组、高蛋氨酸组和叶酸、维生素B12组，C57BL/6鼠为对照(C57)，以相应饲料喂养4个月后取材，测定血糖、血同型半胱氨酸、叶酸和维生素B12，以PAS、六氨银染色法光镜下及超微电镜观察各组DN病变，比较各组肾小球硬化指数；以免疫组化和半定量图像分析肾小球MMP-9蛋白表达，并以RT-PCR检测肾脏MMP-9 mRNA水平。

His exceptional social benefits have placed it to the worldly eyes like the great favorite for to achieve the worldwide title, but the two breakings of the past Sunday, an oil leak in Raikkonen's car and an engine trouble in the one belonging to Massa have cooled something tempers.

他的特殊社会效益放在它以世俗的眼睛一样伟大的最爱，为实现世界范围内的名称，但两地breakings的过去周日，石油泄漏，在莱科宁的赛车和一个引擎发生故障，在一个属於马萨有冷却一些脾气。

The obtained activation barrier of β-scission of 1-butene is 217 kJmol^(-1) in the reverse reaction of ethene dimerization.

反应的逆过程也就是1-丁烯在酸性分子筛表面的1-丁基烷氧化合物发生B分裂反应，计算所得相应的l-丁烯B分裂反应的能垒为217kJmol^(-1)，远高于相应的乙烯二聚反应能垒。