比较原理

By using Floquet theory, Comparison theorem of impulsivedifferential equation and analytic method, we investigate the dynamics of thesystem in detail.

通过利用脉冲微分方程的Floquet理论和比较原理，证明了当脉冲周期小于某个临界值时，系统存在一个全局渐近稳定的害虫根除周期解，最后给出了系统持续生存的条件。3。

The main aim of this thesis is to extend some results of classical convex analysis to notions of Carnot groups, which contain the inequalities of Hadamard type, the Lipschitz continuity, the comparison principle and the second order derivatives for convex functions on Carnot groups G and regularity of quasiconvex functions on G.

本文的主要目的是推广欧氏空间凸分析中的一些结果到Carnot群上凸分析的情形，其中包括Carnot群上凸函数的Hadamard型不等式、Lipschitz连续性、比较原理、二阶可微性及拟凸函数的正则性问题。

We are interested in the complicated interactions among multi-nonlinearities from double degeneracy and source and flux.

本文所考虑的双重退化模型一般不具有古典解，而只能从弱解及相应的比较原理出发。

Next,critical global existence exponent and critical Fujita exponent are proved for the half space problem to a doubly degenerate parabolic equation with nonlinear flux condition.

其次，对一类具有非线性边界流的双重退化抛物型方程半无限问题，运用比较原理给出了解的整体存在临界指标和Fujita临界指标。

This kind of equation is from diffusion process with jumps and has important application in stochastic control and finance mathematics.

本文研究一类带有非局部积分项的完全非线性椭圆型方程粘性解的比较原理，这类方程源自带跳跃的扩散过程，在随机控制，金融数学中有广泛而重要的应用。

In this paper we mainly utilize super and sub solution techniques, use comparision principle and construct appropriate supersolution and subsolution by eigenfunctions to discuss two kinds of nonlocal nolinear parabolic systems with homogeneous Dirichlet boundary condition.

两类非线性抛物方程解的整体存在与爆破性质本文主要利用上下解方法，运用比较原理，通过特征函数等构造适当的上下解讨论了两类抛物型方程组解的整体存在与爆破。

Firstly, we investigate the Dirichlet problems comparison principle on a bounded subset for this fully nonlinear intergro-differential equation, at the same time we must assume the measure in the intergro-differential item is absolute continuous.

首先研究这类完全非线性积分微分方程在有界区域上Dirichlet问题的比较原理，此时须假设积分项所涉及的测度是绝对连续的。

In this paper, a disease transmission model of SEIRS type with exponential demographic structure is studied. Two sufficient conditions are obtained to guarantee the local or global exponential stability of the disease free equilibrium by using a new technique based on the concept of comparison.

本文研究了一类具指数人口统计与结构的SEIRS传染病模型，利用一种新的基于比较原理的分析，获得了无病平衡点局部和全局指数稳定的两个充分条件。

The existence of the radially classical solutions with Dirichlet boundary value in unit ball was investigated. Based on perturbation technique, topological method and comparability theorem, the existence of the radially symmetric solutions for the generalized mean curvature equations with proper presupposition was established.

在单位球内考虑广义平均曲率方程组具有Dirichlet边值条件的径向古典解，运用摄动技巧、拓扑方法及比较原理，在一个适当的条件下，证明了广义平均曲率方程组径向对称解的存在性。

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。

I am sure after a few weeks of adaptation and familiarization I will have no difficulty in functioning on a daily basis in an English speaking society or in participating fully in graduate studies.

在大学的三年的学习生活不仅给予我自身的充实，更重要的是磨练和培养了我较强的自觉能力和严谨，踏实的作风以及不怕困难的精神，对未来充满了信心！

As the first volcanoes erupted, one of the gases that bellowed out was steam.

在第一批火山喷发时，喷出的气体之一就是水蒸汽。