随机

Aim at the efficiency and precision of the stochastic FEM, two kind of new stochastic FEM are put forward and the correlative theories and methods are established:1 The stochastic FEM based on Gauss integral methodEstablish the method of Stochastic FEM based on the Legendre integration.

本论文针对如何提高非线性结构随机有限元计算精度和效率，提出了两种新的随机有限元法，建立了相应的理论和方法，具体如下： 1、Gauss类积分随机有限元方法建立了基于Legendre积分的随机有限元方法。

A two dimensional stochastic nonlinear dynamical model of semi-active suspension system is presented considering the stochastic factor of the road. The Hamilton function is also described as one dimension diffusion process by using stochastic average method, the stationary stability is studied by solving the Fokker-Planck-Kolmogorov equation. The Backward Kolmogorov equation for reliability function had been established.

考虑路面随机因素的影响，首先建立二自由度汽车半主动悬架的随机非线性动力学模型，运用随机平均法，将Hamilton函数表示为一维扩散过程，并运用奇异边界理论分析系统的全局随机稳定性，建立可靠性函数所满足的Backward Kolmogorov方程，结合初始条件和边界条件得出数值结果。

In essence, stream cipher is such a pseudorandom generator that its chaos sequence of output and random sequence are computational indistinguishability; and the aim in designing block cipher materially is to design a pseudorandom permutation which is computationally indistinguishable from random permutations.

实际上，序列密码本质上就是一个伪随机生成器G，其输出的乱数序列和随机序列是计算不可分辨的；而分组密码的设计目标实质上就是设计一个伪随机置换，它与随机置换是计算不可分辨的。

Some fundamental properties of four arithmetic operations, intersection and union operation, supremum、infimum as well as superior limit, inferior limit and limit operation of bounded closed complex fuzzy numbers are studied.

为了描述这类动态模糊随机现象演化过程的规律性和有效地解决受模糊随机因素影响的振动工程问题，本文建立了严谨的模糊随机过程论和模糊随机振动理论。

This dissertation focuses on the vector stochastic integral and its applicationsto mathematical finance. We first conduct a comprehensive study on VSI and provide aneconomical justification on the question of why VSI is more suitable than the component-wise stochastic integral for mathematical finance.

本论文以向量随机积分为主线，首先较为系统地研究了向量随机积分，给出了在金融数学中使用向量随机积分较之使用按分量的随机积分更合理的经济学解释。

Under some conditions, we prove that random nonuniformly exponential dichotomy actually imply random uniformly exponential dichotomy. And, using the normal Lyapunov exponents, we also obtain a sufficient condition under which a random compact and invariant subset is a random forward attractor. This is a generalization of the results of Ashwin\'s.

在一定条件下，我们证明了随机非一致指数二分性蕴含着随机一致指数二分性，同时，利用法向Lyapunov指数，我们还给出了一个紧致的随机不(来源：A5cBc765C论文网www.abclunwen.com)变集能成为随机吸引子的一个充分性条件，推广并改进了Ashwin的一些结果。

Both LDPC codes and OFDM technology are studied in this paper. The working and the results obtained are summarized as follow:1. The definition of LDPC codes and its coding/decoding ideas are systematically summarized, a general algorithm of changing any parity-check matrix to lower triangular form, which is suitable for quick encoding, is given out, along with a girth checking algorithm. Absolutely random LDPC codes construction is improved, a new half random construction of LDPC codes with linear time coding and no 4-cycles is brought out.

系统地阐述了低密度校验码的定义及编译码原理，提出了一种将任何校验矩阵变换成适于快速编码的近似下三角形式的通用算法及一种围长检测算法，对完全随机的校验矩阵构造法进行了改进，提出了一类消除4环且可近似线性编码的校验矩阵半随机构造法，仿真表明，在高编码效率情况下，改进后的半随机构造法，其性能稍优于完全随机构造法，并可以线性时间编码，因此更适合实际应用。

Phage display of recombinant human lymphotoxin mutation librariesand receptor affinity screeningContraction of conformable large molecule mutation library is pivotal for molecular evolution study in vitro. In order to extend the range of the screening region of amino acid in LT gene, several receptor binding sites of LT were mutated randomly by overlap PCR amplification with the random nucleotide primers, the R46, S106, L130 combined site-directed random mutation library and R46~A52, S106~F110, R46~A52 + S106~F110 region random mutation libraries of rhLT were constructed successfully.

二。重组人淋巴毒素噬菌体库的构建及受体亲和筛选构建适合的大容量生物大分子变异体文库是进行体外分子进化研究的关键，为了扩大LT基因序列中被筛选的氨基酸范围，我们采用含随机核苷酸序列的引物，通过Overlap PCR的方法对LT的受体结合区域进行多点随机突变，分别构建了rhLT R46+S106+L130三点随机突变组合文库和R46～A52、S106～F110、R46～A52+S106～F110区域随机突变体库。

This paper, the future market conditions as a random event, according to the probability of higher mathematics in the theory of the future market and the level of information, analysis and evaluation of mathematical expectation of random variable as a random variable reflects the average level, it is important to the probability of random variable characteristics.

本文把未来市场状况作为随机事件，依据高等数学中的概率理论，对未来市场和信息的水平作出分析和评价，由于随机变量的数学期望体现了随机变量的平均水平，它是随机变量的重要概率特征。

Considering the randomness of the structural physical parameters and utilizing the random variable's functional moment method and the algebra synthesis method, the mean value and the variance of the mean square value of the structural displacement response under stationary random excitation are computed firstly from the expressions of structural stationary response in frequency domain. And then the expressions of the mean value and the variance of stochastic rigid frames dynamic reliability are educed from the Poisson formula of calculating dynamic reliability.

考虑结构的物理参数具有随机性，从结构随机响应的频域表达式出发，利用求解随机变量数字特征的代数综合法和矩法，导出随机参数刚架结构在平稳随机激励下的位移及速度响应均方值的数字特征，再由动力可靠性的Poisson公式导出结构动力可靠度的计算公式。

The absorption and distribution of chromium were studied in ryeusing nutrient culture technique and pot experiment.

采用不同浓度K2CrO4(0，0.4，0.8和1.2 mmol/L)的Hoagland营养液处理黑麦幼苗，测定铬在黑麦体内的亚细胞分布、铬化学形态及不同部位的积累。

By analyzing theory foundation of mathematical morphology in the digital image processing, researching morphology arithmetic of the binary Image, discussing two basic forms for the least structure element: dilation and erosion.

通过分析数学形态学在图像中的理论基础，研究二值图像的形态分析算法，探讨最小结构元素的两种基本形态：膨胀和腐蚀；分析了数学形态学复杂算法的基本原理，把数学形态学的部分并行处理理念引入到家实际应用中。