查询词典 discrete optimization

Taking a heavy truck cab as the example, a model of the spotweld space based on finite element was built to analyse the torsional stiffness of the model, and the amount and layout of the spotweld using the discrete variable topology optimization were optimized. Comparing with the original model in welding spot's number and the torsional stiffness, the optimized model has less number of welding spot, but the torsional stiffness of the two model is almost the same.

以某重型卡车驾驶室为例，在有限元模型基础上建立焊点空间模型进行扭转刚度分析，并采用离散变量拓扑优化方法对焊点的数量及空间布局进行优化，通过优化前后的对比可知，优化后在不降低扭转刚度的同时减少了焊点数目。

Then its optimization result was presented by means of genetic algorithm because of some discrete parameter , complicated target function and inequation constraint.

考虑到该优化问题的目标函数非常复杂且涉及到不等式约束、离散变量的处理技术等问题，采用了基于遗传算法的优化计算方法。

Based on characteristics of NEC VR4122(μPD30122) microprocessor, optimization methods on IMDCT(Inverse Modified Discrete Cosine Transform) of Ogg Vorbis audio decoding program are presented.

针对NEC VR4122(μPD30122)微处理器的特点，从算法优化和存储空间优化2个方面，对开放源代码的Ogg 音频解码的IMDCT进行性能优化。

Keywords:lattice shell; optimization design; full stress criterion; genetic algorithm; discrete variable

关键词］网壳结构；优化设计；满应力准则；遗传算法；离散变量

We construct algorithms in which directions are computed by these two systems and the step-sizes are generated by Armijo line search to solve the original constrained optimization problem and prove that the discrete scheme based on the differential equation system with the second order information has the locally quadratic convergence rate under the local Lipschitz condition.

我们构造了搜索方向由两个微分系统计算，步长采用Armijo线搜索的算法分别求解这个约束最优化问题，在局部Lipschitz条件下基于二阶信息的微分方程系统的迭代方法具有二阶的收敛速度。

Based on analysing the respective characteristics of regular PID controller in trational control theory and fuzzy logical controller in intelligent control theory, the idea and technique of expert system is introduced to develop a novel kind of hybrid intelligent controller. It can coordinate two kinds of control algorithms and tune the control parameters on-line for different working zones of the controlled process.(3) The hybrid knowledge expression model, which combines discrete state space model, fuzzy relational model and rule base model, is proposed based on analysing the characteristics of all kinds of knowledge expression models. The knowledge of the controlled process in different aspects can be expressed resonably by it. Based on the model mentioned above, the related optimization strategy for complex system is developed.

本文的主要贡献体现在：（1）以炼油厂的催化裂化装置和钢铁联合企业的大型焦炉装置两个典型的复杂工业过程为例，分析了工业大系统的许多不易控制的特性，并归纳了其中的几个典型特征；（2）针对经典控制理论中的常规PID调节器和智能控制技术中的模糊逻辑控制器各自的特点，通过引入专家系统的思想和方法，开发了一类混合式专家控制器，它同时具备在线协调两种不同控制规律和自动学习控制规则的能力；（3）通过分析各种知识表达模型的特点，提出了一类包括离散状态空间模型、模糊关系模型和规则基模型在内的混合知识表达模型，它能对过程知识在各个不同侧面给予合理的描述。

ABSTRACT Sample path perturbation analysis is a newly-developed approach for the study of discrete event dynamic systems. PA has many advantages and is very effective in parametric analysis and optimization.

摄动分析是近年来提出的一种研究离散事件动态系统的新方法，它具有许多优点，在进行参数分析和优化时特别有效。

This paper proposed a modified Particle Swarm Optimization algorithm to solve the mixed model assembly line sequencing problem in discrete space with two objectives:total production rate variation and total idle-overload time.

提出在离散空间用一种改进的微粒群优化算法来解决混流装配线的多目标排序问题，考虑两个目标：总生产变化率最小和总闲置－超载时间最小，并对两个目标函数进行了规范化处理以消除量纲的影响。

Combination optimization problem has many extensive application backgrounds, and its objective is to find the optimal combinations of discrete status in the solution space.

组合优化问题具有广泛的应用背景，它的目标是寻找解空间中离散状态的最优组合。

SUI Yunkang, different filter functions of element weight, element allowable stress and element stiffness are introduced to change the 0-1 type discrete topological variables to continuous topological variables between 0 and 1, thus a topological optimization model with continuous topological variables is built.

删除无效约束技术就是在近似射线步以后，根据一定的准则，将约束分为无效约束和有效约束，删除无效约束，保留有效约束，减小优化模型的规模，提高求解效率。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。