查询词典 selection

Under only supposed each indidual utility function possessing some continuity, an existence theorem of selection for minority submitting to the majority is got,and prove...

通过在不同空间上构造委员会的偏好结构，指出了这种偏好的锥诱导性和这种偏好的有效选择与多目标决策问题的M－解之间的等价性。

The book is divided into 14 chapters, including Introduction, continuous control system theory, process and discrete sampling, Z transform, sampled-data systems, discrete approximation of continuous system the equivalent, based on mathematical transform the classical design method, based on state space pole placement design methodology, multi-variable system of quadratic optimal control, quantitative effects, the choice of sampling period, the digital control system modeling, digital control system for a variety of design methods, variables quadratic optimal control systems, sampling cycle of selection, non-linear control of the problem, as well as digital control system, a typical application - Disk drive servo control design.

全书共分14章，内容包括概论、连续控制系统理论、采样过程和离散化、Z变换、采样数据系统、连续系统的近似离散等效、基于数学变换的经典设计方法、基于状态空间的极点配置设计方法、多变量系统的二次型最优控制、量化效应、采样周期的选择、数字控制系统的建模问题、数字控制系统的各种设计方法、变量系统的二次型最优控制、采样周期的选择、非线性控制的有关问题，以及数字控制系统的一个典型应用——磁盘驱动器的伺服控制设计等。

The flume's design includes the selection of the material, thickness, contractibility and how to use UG to plot it.

塑料水槽的设计的内容包括制品的材料选择，壁厚的确定，收缩率的确定以及用UG软件绘制的过程。

In chapter one, a review for the trade of urban rail traffic is performed with respects to the developing histories and trend, mode, light rails, vehicle type and so on; In chapter two, a set of contradistinctive analyses between the domestic and the overseas are carried out at aspects of equipment, density of line net, build cost and so on. In chapter three, the competitive status among existing enterprises for urban rail vehicle and equipment manufacturing in our country is analyzed by Potter model; In chapter four, questions that should be paid attention to and strategies in course of our country's urban rail traffic building are provided mainly in terms of plan, cost, construction investment and operation, selection of system type, safety of building process and so on.

本文第一章主要从轨道交通的发展历史、模式、轻轨、车辆类型、发展趋势等方面对城市轨道交通行业的发展作了一个回顾；第二章主要是从设备、线网密度、建设成本等六个方面对国内外城市轨道交通进行了一个对比分析；第三章主要是利用波特模型对我国现有的城市轨道交通车辆设备生产企业之间的竞争状况进行了分析；第四章主要从规划、成本、建设投资和运营、系统类型选择、建设过程安全等方面提出了我国在城市轨道交通建设过程中应该注意的问题和对策。

The heuristic method emploies a genetic algorithm in reducing the redundant attributes of all attributes. Besides taking fitness function as its heuristic function for its selection operation, the genetic algorithm uses the attribute\'s information entropy to construct the heuristic function for its mutate operation, and in this way it markedly elevate the convergence speed of attribute reduction.

启发式方法采用遗传算法进行属性约简，除了存在于选择操作的适应度启发函数外，还在变异操作中以信息熵为基础构造了启发函数；穷举方法基于循环队列自底向上约简，通过剪枝有效地提高了属性约简集的穷举速度。

Because of the problem of convergence, the key techniques to complete the one step simulation were explored thoroughly. The geometry mapping method based on finite element model and inverse deformation was developed to get the approximate initial blank for one step simulation. The effective selection of convergence factor in Newton-Raphson method was studied. The divergence criterion in iterative process for one step simulation was put forward. Also the countermeasure to ill equations coefficient matrix was studied.

由于存在收敛性的问题，本文重点研究了一步模拟方法计算机实现的关键技术：提出了基于有限元模型的几何映射方法和反向变形方法来确定初始毛坯的近似解，研究了带收敛因子的Newton-Raphson方法中如何高效地选取收敛因子，提出了一步模拟迭代求解过程中的发散准则，并研究了病态方程组系数矩阵的修正方法。

To overcome the premature of simple genetic algorithm, the calculating efficiency of SGA is improved by the following two ways; Firstly, in order to ensure convergence of algorithm and reduce influence factor of convergence, elitist selection and adapted crossover and mutation operator are adopted. Secondly, because this study deals with finding minimize volume of structure, to quicken convergence of this problem, in line with mechanics criterion the paper carry out mutation to some genes in chromosome according to variations of internal force. This will let algorithms to search answer with our hoping directions.

针对基本遗传算法存在早熟的问题，本文主要从两个方面进行了改进，首先为了保证算法的收敛和减少影响算法收敛因素，采用了最优保护策略和自适应的交叉和变异算子；其次，由于本文研究内容涉及求结构最小体积问题，为了加快此类问题的收敛速度，本文结合结构优化中的力学准则，对个体染色体中的某一段基因按照内力变化进行变异操作，使得算法按一定方向进行搜索最优解。

The law of the influence of contractive angle of taper nozzles and curvature radius of convergence nozzles' convergent section on jet structure parameters is revealed, and it can provide a basis for optimization selection and design about laser cutting nozzles.

揭示锥型喷嘴收缩段收缩角、收敛型喷嘴收敛段抛物线曲率半径对射流的流场结构参数的影响规律，为激光切割喷嘴的优化选择和设计提供有效依据。标签激光技术激光切割会聚型喷嘴流场结构流体动力学 laser technigue laser cutting assemble nozzle jet structure hydrokinetics

In accordance with discrete, non-symmetry and time-delay feedback neural networks, we provide some theoretical criteria to judge the stability for designing the networks. On continuous feedback networks, we built an algorithm to estimate the convergence region. On the HNN feedback networks, an effective optimization algorithm based on the annealing strategy and the chaotic neural network is presented, and some disciplinary conclusions are provided to guide the selection of parameters. Simulation results on benchmark problems demonstrate that the performances of our algorithm are distinctly superior to those of the classic HNN based on gradient descend and stochastic optimization methods based on probabilistic distribution.

针对离散、非对称和时延等三种类型的动态反馈网络，给出了可用于网络设计的稳定性判别准则；针对连续动态反馈网络，建立了其收敛域估计的一个算法；针对以HNN模型描述的动态反馈网络，基于退火策略和混沌神经网络提出了一种高效的优化算法，建立了可用于指导参数选择的一些规律性结论，对典型算例的仿真研究显示，改进算法在各类性能上相对基于梯度下降的传统HNN模型和基于概率分布的随机优化算法，具有明显的优越性。

However, there are still some shortages for GA, such as searching algorithms in solution space, convergence of solutions and selection of controls parameters.

然而在应用中发现，遗传算法尚存在诸多不足有待完善，如：解空间搜索策略，问题收敛性，控制参数设置等，这也是它之所以长期成为国内外计算智能研究热点。。。

We were cousins—his grandfather was King of Scots,and his great-grandfather was Henry VII of England.

我们是堂姐弟——他的祖父曾是苏格兰国王，他的曾祖父是英格兰的亨利二世。

I do want to help you, but I am in a quandary now!

我是想帮你，但是我现在左右为难啊！