查询词典 random function

PSO is a population-based optimization algorithm, which mimics the social behavior of animals in a flock. It makes use of individual and group memory to update each particle position allowing global and local search optimization. The objective function considered was the total weight of the structure subjected to stresses, displacements and forces constraints. The effects of the parameters were investigated as well and such combination of tuning parameters promote a better global search behavior avoiding premature convergence while rapidly converging to the optimal solution. Results showed the effectiveness of the proposed method by comparing with ANSYS Design Optimization Tool (zero-order method). The PSO with the tuning parameters makes it an ideal method for offshore wind turbines foundations optimization tasks.(2) A reliability analysis method for pile foundation bearing axial loads based PSOThe performance function of pile foundation's axially bearing capacity sometimes is nonlinear and complex, on the basis of geometric meaning of structural reliability index, an optimum model with PSO for structural reliability analysis under arbitrary random variables was established, The PSO algorithm is very efficient to solve global optimization problemsIts use in structural reliability field presents not only the advantage of its facility of implementation, but also the possibility to obtain the design point and the failure probability with a good accuracy. In addition, PSO is a zero order algorithm, for no derivative is necessary for its implementation.

本文的研究针对桩式海上风机基础结构的特点，在国内外有关研究成果的基础上对海上风机基础结构优化设计理论和可靠度方法一些相关问题进行了较为深入的研究，具体做了以下几个方面的工作：(1)基于粒子群优化的桩式海上风机基础确定性优化设计方法桩式海上风机基础的优化设计是一个复杂的、非线性约束的优化问题，针对传统的基于梯度信息的优化方法在处理非线性问题中易陷入局部最优解的问题，本文将一种耦合惩罚函数的PSO算法引入到海上风机基础结构概念设计中，PSO算法是从群体动物聚集觅食这一活动中受到启发而发展的，该算法利用个体和群体的信息共享不断改进自身的位置从而进行局部和全局最优搜索，本文中以桩和三脚架连接段直径及壁厚为设计变量，以基础总重量作为优化的目标函数，在给定的约束条件下建立了三脚架基础优化数学模型，另外本文还研究了PSO参数变化对结果的影响，协调的参数组合可以避免陷入早熟收敛而能够快速的获得全局的最优解，通过与ANSYS优化模块的计算结果比较验证了该方法的有效性，本方法为海上风机基础的确定性设计提供了一条有效的途径。

The property of continuous function and the formula of probability addition to the convergence in probability of continuous function sequence of random vector is used.

摘要将依概率收敛的一维随机变量序列的连续函数仍依概率收敛的结论推广到随机向量序列的情形。

From the statistical meaning of random load action, the cumulative distribution function and probability density function of equivalent load are developed according to the property of order statistics when load acts for many times.

从载荷作用的统计学意义出发，根据顺序统计量的性质，建立载荷多次作用时等效载荷的累积分布函数和概率密度函数。

Secondly, by the P-L estimation of survivor function, this paper proposed the regression models of polynomial cumulative hazard function distribution models, respectively in the case of complete date and random right censoring date; meanwhile generalized least squares estimations of unknown parameters were proposed respectively using two steps algorithm and principal component analysis algorithm.

与已有的关于多项式危险函数模型的研究成果相比，首先本文在统计模型的构造上充分考虑了累积危险函数乘积限估计量的非独立性，给出了协方差矩阵的估计；其次在模型检验方面，本文利用非参数回归分析方法，充分利用了数据本身的信息，减少了对回归关系假定的主观因素，因而分析结果更为可靠。

The current sensitivity probability density function of energetic materials was deduced based on Frank-Kamenetskii parameter and resistance supposing as stochastic variable of normal distribution, by the application of the probability density formula of function in two random variables.

将Frank-Kamenetskii参数和电阻假设为正态分布的随机变量，应用二维随机变量函数的概率密度公式，推导出了含能材料电流点火感度的概率密度函数。

Because of the random of the membership function, which aggregator to be selected and the non-linearity of system, the fuzzy decision goal function is non-convex commonly.

由于隶属度函数定义的任意性、合成算子选择的不同和控制对象的非线性，模糊决策目标函数的优化一般是非凸优化问题。

Secondly,the deterministic equivalence problem of theprobabilistic inequality is discussed,and the expression formula of thedeterministic equivalences for several commonly used probabilitydistributions,such as normal,exponent,uniform,β and Γ distributions etc.,are given for the linear function with respect to random variables,which solvesthe problem of the deterministic equivalence for the linear-function-class.

其次，本章讨论了概率不等式的确定性等价问题，就随机变量的线性函数类，给出了与几种常用的概率分布，如正态分布、指数分布、均匀分布、β分布、Γ分布等等，相关的确定性等价问题。

In the graph of this example noise function, the red spots indicate the random values defined along the dimension of the function.

图中这个噪声波的例子中，红点表示定义沿着在函数维上的随机值。

In allusion to Funar Conjecture :"If a random triangle lies in a closed unit square,then its inscribed circle s radius,r≤(5-1)/4",an equivalent minimum problem about a function of 2-variables is studied;the stagnation point and its value,value on the boundary of the function of 2-variables are studied,the equivalent problem is proved correct,so the Funar Conjecture is proved correct.

针对Funar猜想："设任意三角形位于闭单位正方形内，则该三角形的内切圆半径，r≤(5-1)/4"，研究了与其等价的某二元函数的最小值问题；利用对此二元函数驻点及其取值、边界取值讨论，证明了等价问题成立，进而此Funar猜想得证。

The relation between the limit state function of large and complex structural systems and input random parameters is always unknown. A quadratic polynomial is considered to simulate the physical limit state function.

工程中大型、复杂结构的极限状态方程与输入随机变量的关系往往是未知的，利用响应面法，用一个二次多项式来模拟结构的极限状态方程。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。