一阶

Many high-rise buildings can be simplied into variable cross-section cantilever beam, which equation of free vibration is variable coefficient differential equation of higher order and there is no general solving process for which in mathematics.

对这类方程，数学上没有提供一般的解法。本文采用的级数解法可求出任何变系数的四阶微分方程，在给定边界条件下的解。

This paper proposes an equivalent second order elastic wave equation to solve the problem of being unable to completely separate the coupled P and S wave by full elastic wave equation.

给出了一种等价的二阶弹性波动方程，以解决弹性波场中完全弹性波动方程不能完全分离耦合的纵、横波波场问题。

Based on the equivalent transformation from fuzzy possibility distribution to random probability density distribution, the fuzzy random failure probability calculation can be formulated easily, and a First Order and Second Moment method for fuzzy - random analysis is established.

提出了模糊随机可靠性分析的近似解析和数字模拟综合方法，基于模糊变量的等价随机化变换，可以方便地得到模糊随机失效概率的计算公式，并建立了模糊随机可靠性分析的一次二阶矩法。

An approach for structure dynamic modification based on an exact solution is proposed.

提出了一种高阶累积量在结构诊断中的应用的方法。

In view of the third purpose, time series method is applied, by means of Sylvester Expansion Theorem, this paper improves an algorithm of constructional analysis of l...

本文基于建模目的3，应用时间序列方法，依据Sylvester展开定理提出一种线性系统结构分析的算法，并给出线性系统的一个简易定阶法。

In order to solve the special technical problems, a structure model with double-stair and multiple-stage compression was given, the structure of pressing chamber of present screw press was improved, and a laboratory-scale cold expeller was designed and manufactured.

针对双低油菜籽脱皮籽仁在冷榨过程中存在的一些关键技术问题，提出了双阶多级压榨的冷榨结构模型，对现有的螺旋榨油机的榨膛结构进行了改进，设计并制造了一种小型实验型冷榨机。

Perhaps you are president who keeps aloof, perhaps is disdains by under the step which as soon as the human raises imprisoning, perhaps is thousands of nameless inactivity extraordinariness, but in each person's parents' eye all is the most lovable child, does not divide the north and south, regardless of the ancient and modern, the parents really love is eternal, through ancient times invariable.

或许你是高高在上的总统，或许是不屑被人一提的阶下之囚，或许是千万个无名无为的平凡者，但在每个人的父母的眼中都是最可爱的孩子，不分南北，无论古今，父母真挚爱是永恒的，亘古不变。

This dissertation investigates the construction of pseudo-random sequences (pseudo-random numbers) from elliptic curves and mainly analyzes their cryptographic properties by using exponential sums over rational points along elliptic curves. The main results are as follows:(1) The uniform distribution of the elliptic curve linear congruential generator is discussed and the lower bound of its nonlinear complexity is given.(2) Two large families of binary sequences are constructed from elliptic curves. The well distribution measure and the correlation measure of order k of the resulting sequences are studied. The results indicate that they are "good" binary sequences which give a positive answer to a conjecture proposed by Goubin et al.(3) A kind of binary sequences from an elliptic curve and its twisted curves over a prime field F_p. The length of the sequences is 4p. The "1" and "0" occur almost the same times. The linear complexity is at least one-fourth the period.(4) The exponential sums over rational points along elliptic curves over ring Z_ are estimated and are used to estimate the well distribution measure and the correlation measure of order k of a family of binary sequences from elliptic curves over ring Z_.(5) The correlation of the elliptic curve power number generator is given. It is proved that the sequences produced by the elliptic curve quadratic generator are asymptotically uniformly distributed.(6) The uniform distribution of the elliptic curve subset sum generator is considered.(7) We apply the linear feedback shift register over elliptic curves to produce sequences with long periods. The distribution and the linear complexity of the resulting sequences are also considered.

本文研究利用椭圆曲线构造的伪随机序列，主要利用有限域上椭圆曲线有理点群的指数和估计讨论椭圆曲线序列的密码性质——分布、相关性、线性复杂度等，得到如下主要结果：(1)系统讨论椭圆曲线-线性同余序列的一致分布性质，即该类序列是渐近一致分布的，并给出了它的非线性复杂度下界；(2)讨论两类由椭圆曲线构造的二元序列的"良性"分布与高阶相关性(correlation of order κ)，这两类序列具有"优"的密码性质，也正面回答了Goubin等提出的公开问题；(3)利用椭圆曲线及其挠曲线构造一类二元序列，其周期为4p(其中椭圆曲线定义在有限域F_p上)，0-1分布基本平衡，线性复杂度至少为周期的四分之一；(4)讨论了剩余类环Z_上的椭圆曲线的有理点的分布估计，并用于分析一类由剩余类环Z_上椭圆曲线构造的二元序列的伪随机性；(5)讨论椭圆曲线-幂生成器序列的相关性及椭圆曲线-二次生成器序列的一致分布；(6)讨论椭圆曲线-子集和序列的一致分布；(7)讨论椭圆曲线上的线性反馈移位寄存器序列的分布，线性复杂度等性质。

A new method of implementing high order FIR filter with FPGA is presented.

提出一种新的高阶FIR滤波器的FPGA实现方法。

In order to compute the failure probability of structural systems for stability of gravity retaining walls, firstly, two performance functions against overturning and sliding of gravity retaining walls were established. Then, the first order second moment theory in structural reliability analysis, i.e., the checking point method was introduced to compute the two failure modes respectively, and two corresponding reliability indexes could be obtained.

为了计算重力式挡土墙稳定性的结构体系失效概率，首先分别建立重力式挡土墙结构抗倾覆稳定性和抗滑移稳定性的功能函数，然后引入结构可靠度分析一次二阶矩法中的验算点法分别对两种失效模式进行计算，得出两个相应的可靠度指标。

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。