极限函数

The semi-low normal distribution membership function of fatigue limit is determined, and the anti-fatigue fuzzy reliability compute formula of rotor is deduced. The fuzzy reliability model of rotor anti-fatigue is set up. Taking an internal shaft of the rotor of aero electric generator for an example, its reliability design can be realized by adopting the anti-fatigue reliability design theory presented in the dissertation.

首次确定出了疲劳极限降半正态分布形式的隶属函数，推导出了转轴抗疲劳的模糊可靠度计算公式，建立了转轴抗疲劳的模糊可靠性模型；以航空发电机转子内轴为例，对其进行了抗疲劳的可靠性设计，并用本文建立的抗疲劳的模糊可靠度计算公式，对其进行了模糊可靠性校核。

To fulfill the requirement of preliminary design,uniform design method is proposed to make parametric analysis and approximate optimization.

作为算例，对一个柱支承预应力扁网壳进行了参数分析，得到了网壳用钢量、变形和极限荷载系数与三个主要设计参数(单层部分材料设计应力折减系数、单层部分范围和预应力值)之间的近似函数关系，并找出了满足规范要求的各参数之间的较理想的最优水平组合。

Since the concept of NA have a lot of applications in multivariate statistical analysis, reliability theory and percolation theory, various aspects of NA are significant and have been investigated by a host of scholars Fist, we give some Fuk-Nagaev type probability inequalities, moment inequalities of maximal partial sum for sequence of NA random variables, and some strong law of large numbers and complete convergence for sequence of NA random variables are obtained.

在本论文中我们对不要求强平稳或同分布的NA随机变量列进行了多方面的研究：首先对NA列建立了一组具有NA特点的关于最大部分和的Fuk-Nagaev型概率不等式及其关于某一类特定函数的矩不等式，它们在后续给出的极限定理的证明中发挥着重要作用；研究了具有不同分布的NA列的强收敛性，如对NA列建立了更一般条件下的Wittmann型强大数律及完全收敛性，同时也进一步改进了R。

Based on the simplified theoretical solution deduced by the authors,the temperature profiles in the burner,the flammable limit and maximum half cycle were theoretically predicted by a piecewise linear function.

借助于先前推导的简化理论解，利用分段线性函数，构建了燃烧器内温度分布曲线、可燃极限和最大半周期。

The advantages and limitations of every kind of methods for calculating the failure probability is reviewed. The frist order reliability method, the second order reliability method and many kinds of boundary method have achieved remarkable success and formed nature fields of reliability. However, the precision of these methods decrease as the increase of complexity of problem. The numrical methods are versatile, except numerical intergration is only adaptable to special problems which have small number variables and regular intergral domain. Particularly, the advanced variance reduction techniques own the following character: high precision and a small amount computation. But some questions remain to study in the future because only an initial work about these techniqes is developed.

全面评述了计算失效概率各种方法的优点和局限性，其中经典的解析法包括一次可靠性方法、二次可靠性方法、一阶边界法、Vanmarcke上边界、PENT上边界和Ditlevsen二阶窄边界法，这些方法对于多设计点、变量较多且相关、密度函数不是正态以及极限状态方程较复杂的情况，其计算精度较差；而已有的数值方法却是具有较好的通用性，其中除数值积分法只对变量较少、积分域较规则的特殊问题适用外，各种数值模拟方法均具有较广的适应性，特别是各种改进的方差减小技术，精度高、计算量小，但由于其处在研究的初级阶段，还有许多问题有待于解决。

Secondly, the existence of chaos in a special class of discrete-time neural network models with sinusoidal activation function in the sense of Devaney with some parameters of the systems entering some regions are rigorously presented by means of anti-integrable limit method. Whats more, period-doubling bifurcation and saddle-node bifurcation in the neuron model are studied.

其次，利用反向可积极限方法证明了一类周期输入输出函数的离散神经网络模型在参数达到一定范围时产生Devaney意义下的混沌，并讨论了其一维情形的神经元模型出现倍周期分支和鞍-结点分支的情况。

The stability of system equilibrium point and the existence condition of 3-D Hopf bifurcation as well as the stability of hence generated periodic solution were analyzed, so that the existence of limit cycles on the two-dimensional stable manifold of one microbial species and its nutrition was verified when other one had the disadvantage in the competition so as to become extinct.

研究当营养消耗率δ1＝δ1为一般的非减连续函数和δ2＝常数的三维Chemostat模型，分析系统平衡点的稳定性，三维系统经历Hopf分支的条件和由此产生的周期解的德定性，证明系统中某一微生物物种处于竞争劣势而趋于灭绝时另一微生物物种和营养的二维稳定流形上极限环的存在性。

The stability of system equilibrium point and the existence condition of 3-D Hopf bifurcation as well as the stability of hence generated periodic solution were analyzed,so that the existence of limit cycles on the two-dimensional stable manifold of one microbial species and its nutrition was verified when other one had the disadvantage in the competiti.

研究当营养消耗率1δ=1δ为一般的非减连续函数和2δ=常数的三维Chemostat模型，分析系统平衡点的稳定性，三维系统经历Hopf分支的条件和由此产生的周期解的稳定性，证明系统中某一微生物物种处于竞争劣势而趋于灭绝时另一微生物物种和营养的二维稳定流形上极限环的存在性。

In this thesis, using the qualitative theory and stability theory of ordinary differential equation, we study the global stability of equilibrium, existence and uniqueness of limit cycle for a predator-prey model with sublinear functional response function.

本学位论文利用常微分方程定性理论和李亚普诺夫稳定性理论的基本方法，研究了具次线性功能性反应函数的食饵-捕食者模型的平衡点的全局稳定性，极限环的存在性和惟一性。

Generally speaking, the activation function should be symmetric, and the neural network should be trained to a value that is lower than the limits of the function.

一般而言，激活功能应该是对称的，而神经网络应训练的值比函数的极限低。"/页"

Chrysanthemum of 10 thousand birthday is lax to edaphic requirement, with the arenaceous qualitative loam with fecund, good drainage had better.

万寿菊对土壤要求不严，以肥沃。排水良好的砂质壤土为好。

He unstepped the mast and furled the sail and tied it.

他拔下桅杆，把帆卷起，系住。