定理

The existence of the optimal control for the system is demonstrated via compactness theorem and prior estimates.

根据预备知识，利用紧性定理和先验估计，证明了系统最优控制的存在性。

By using the compactness theorem of SBD space, Poincaréinequality onthe BD functions,we prove the existence for variational problems.

主要利用SBD函数空间的紧性定理，BD函数的Poincaré不等式等给出了变分问题的存在性。

Since bounded closed sets in infinite dimensional space are notcompact generally,in order to employ Horn's fixed point theorem the compactness of operator Pis initially proved in section 3 in this chapter.

由于无限维空间的有界闭集一般不具备紧性，为了应用Horn不动点定理，我们先证明了Poincare算子P的紧性。

Firstly, a comparison theorem is proved.

首先，证明了比较定理。

We also give one kind of multi-dimensional comparison theorem of Y.

我们先运用与EL.Karoui在[1]中使用的类似的方法得到了单边界情形K的多维比较定理。

And the comparison theorem of the optimal cost of descriptor systems is given.

并给出广义系统的最优代价比较定理。

This paper gives a proof of a comparison theorem on the viscosity solution of HJB Equation.

证明了与随机控制问题有关的动态规划方程粘性解的比较定理。

We use comparison theorem and a new method to analysis the problem of persistence and extinction.

消费者种群的长期影响，利用比较定理及一种全新的方法对自治Leslie系统给出了种群弱持续生存和灭绝的条件；对拟非自治系统给出了种群弱持续生存和灭绝的阈值。

This paper is in the comparison theorem of Sturm-Liouville problem, based on the type of separation is given.

该文讨论了一类分离边界条件下的Sturm-Liouville特征值问题，就不同的势函数q，分别在右定和左定情形下建立了特征值的比较定理。

In this paper, A class of diffusion systems with nonlinear source were studied, using comparison theorem and method of upper and lower solutions .

本文利用比较定理与上、下解方法研究了一类具非线性源的扩散系统，证明了该系统整体解的存在性与零解的稳定性，推广了C。

We have no common name for a mime of Sophron or Xenarchus and a Socratic Conversation; and we should still be without one even if the imitation in the two instances were in trimeters or elegiacs or some other kind of verse--though it is the way with people to tack on 'poet' to the name of a metre, and talk of elegiac-poets and epic-poets, thinking that they call them poets not by reason of the imitative nature of their work, but indiscriminately by reason of the metre they write in.

索夫农 、森那库斯和苏格拉底式的对话采用的模仿没有一个公共的名称；三音步诗、挽歌体或其他类型的诗的模仿也没有——人们把&诗人&这一名词和格律名称结合到一起，称之为挽歌体诗人或者史诗诗人，他们被称为诗人，似乎只是因为遵守格律写作，而非他们作品的模仿本质。

The relationship between communicative competence and grammar teaching should be that of the ends and the means.

交际能力和语法的关系应该是目标与途径的关系。