界

Three are three major actions that Mn effects fracture behavior in the alloy at room temperature, as follow: One is that Mn fines grains, antiphase domains and weakens dislocation clog, which retain formation of cleavage crackle. The second is that Mn decreases APB energy and promotes slop and cross slip, in particular, a large number of cross slip make deformed APBs transform from line type into zigzag type and the APBs interact and cross each other, resulting in propagation of cleavage cracks. The last is that Mn raises the relative proportion of cleavage strength to grain-boundary strength and then restrains formation and propagation of cleavage crack.

Mn对合金室温断裂行为的影响主要反映在三个方面，一是Mn的存在细化晶粒和反相畴，使得位错塞积程度减小，从而阻碍解理裂纹源的生成；二是Mn的存在提高解理强度与晶界强度的相对比值，从而抑制了解理裂纹的形成和扩展；三是Mn降低反相畴界能量、促进超位错的滑移、交滑移，特别是断裂前位错大量的交滑移使形变反相畴由直线型变为折线"Z"字型，反相畴界间的相互作用、相互交错阻碍了解理裂纹的扩展。

Lastly, the ruin probability of the bidimensional perturbed risk model are studied, whose upper bound of Lundberg-type within infinit-time is obtained and discussed for the case of light-tailed using the martingale technique, the conclusion is gotten that the strength of the dependent of B strongly impact the upper bound can be achieved.

第四章主要研究了带有扰动项的二维风险模型的破产概率，应用鞅论的技巧，在轻尾条件下，求出Lundberg-type在无限时间内的破产概率的上界；并对破产概率的上界进行讨论，获得的相关性的强弱影响着破产概率可达到的上界。

In chapter four, we prove that a complete open Riemmannian manifold with Ricci curvature negatively lower bounded is of finite topological type provided that the conjugate radius is bounded from below by a positive constant and its excess is bounded by some function of its conjugate radius.

第四章，我们证明了对于Ricci曲率具负下界的完备开Riemannian流形，当其共轭半径有正下界且它的Excess被其共轭半径的某个函数所界定时，它就有有限拓扑型。

FR conjugate gradient methods with perturbations are proposed. The global convergence property of the first method is proved under the condition of main directions' sufficient descent. Whereas, in the proof of the convergence for the other two methods, we only need main directions' descent. Importantly and quite interesting, boundedness conditions such as objective function being bounded below, boundedness of level set are not needed. Chapter 5 presents a version of Dai-Yuan conjugate gradient method with perturbations.

在主方向充分下降的条件下证明了第一个方法的全局收敛性，而后两个方法的收敛性是在主方向下降的条件下证明的，这些收敛性证明的一个共同特征就是不需要目标函数有下界或水平集有界等有界性条件，第5章采用Wolfe或Armijo步长规则提出了带扰动项的Dai-Yuanabbr。

The class of nonlinear systems considered is referred to as a semi-strict feedback system and includes parametric uncertainties, input gain uncertainties and the unknown but bounded nonlinear function and disturbance.

论文所研究的非线性系统是一类广泛的半严格反馈系统，系统的不确定性包括有界的参数不确定性，有界的输入增益的不确定性以及未知但有界的非线性方程和外部干扰。

Based on the concepts of bounded operator, positive bounded operator and possible bounded operator their connections are discussed such that the contents are deeper.

在有界算子，肯定有界算子以及可能有界算子这些概念的基础上，进一步讨论它们之间的联系，使得关于这方面的内容更全面深刻。

It is proved that when all the ratios of the generic term of a subaddtive sequence to its ordinal number form a lower bounded sequence,the ratio sequence must have limitation .

从这一结果出发证明了，当定义在(0，+∞)上的次可加函数与其自变量之比为有界函数时，次可加函数必存在上下确界函数，并证明了其上下确界函数均为齐次线性函数。

At the same time, the variational stability of bounded variation solutions at the effect of perturbation and non-perturbation for the impulsive differential system are discussed, the Ljapunov type theorems for variational stability and asymptotically variational stability for impulsive differential systems are established.

同时，讨论了在无扰动和有扰动的情况下，这类固定时刻脉冲微分方程有界变差解的变筹稳定性，建立了此类微分系统有界变差解变差稳定性和渐近变界稳定性的两个Ljapunov型定理。

In chapter two, we study the boundedness of impulsive ordinary differential equati...

第二章，研究了脉冲常微分方程及脉冲泛函微分方程的有界性，得到了方程解的一致有界及最终一致有界的几个充分条件。

All superclasses of closed unbounded classes are stationary and stationary classes are unbounded, but there are stationary classes which are not closed and there are stationary classes which have no closed unbounded subclass ( such as the class of all limit ordinals with countable cofinality ).

所有闭合无界类的超类是固定的并且固定类是无界的，但是有着不闭合的固定类并且有着没有闭合无界子类的固定类(比如带有可数共尾性的所有极限序数的类)。

Plunder melds and run with this jewel!

掠夺melds和运行与此宝石！

My dream is to be a crazy growing tree and extend at the edge between the city and the forest.

此刻，也许正是在通往天国的路上，我体验着这白色的晕旋。