查询词典 combinatorial optimization problem

In this dissertation, we mainly dicuss the applications of semidefinite programming in combinatorial optimization.

本论文主要讨论半定规划在组合优化问题里的应用。

Using semidefinite programming relaxation and randomized rounding, we give the corresponding polyniomal approximation algorithms for some NP-hard combinatorial optimization problems.

我们对于一些NP-难的组合优化问题，采用半定规划松弛和随机舍入的方法设计了多项式时间的近似算法，这些算法的性能比都是目前为止最好的结果。

Using this method, the global risk level of the virtual enterprise is minimized by combinatorial optimization of risk solutions with the constraint straint of risk investment.

该方法能够实现在一定风险费用投入的情况下，通过优化组合风险处理措施，达到虚拟企业整体风险水平最低的目标，是虚拟企业风险规划的科学管理方法。

In order to get out from the cockamamie work in road route design for designers, on the basis of studying the internal relations among local schemes, local scheme was decomposed to small unit logic schemes; the directed network was used to represent the topological connection; the united data structure of point-arc was used to express a network graph. Based on the shortest path theory, the combinatorial optimization algorithm that can search optimal logical schemes of some targets in the network graph intelligently and can form the whole scheme automatically was put forward.

为了使设计者从道路线路设计的繁重计算统计工作中解脱出来，在研究了局部方案间内在关联的基础上，提出了将局部方案分解为更小单位的逻辑方案，用有向网络图表示逻辑方案间的拓扑关系，采用节点－弧段联合数据结构来表示网络图；同时基于最短路径理论，提出了在网络图中智能化搜索综合指标最优的逻辑方案集，自动形成整体方案的组合优化算法。

Reconfigurations are typically large,complex,combinatorial,optimization problems.

但是由于配网本身的结构，其重构是一个非常复杂的大规模组合优化问题。

After a further analysis based on the empirical results,a trial probe on the cognitiveprocessing mechanism of the problem representation of the word problem in two types of MLDwas made by the author.The MRD performed much poorer than the MLD only in the mostdifficult equation listing of word problem and the medium and most difficult problemrepresentation of word problem,which showed no difference in computation and comprehensionof simple meaning of the problem,but the gap between two types of MLD became wide as afunction of difficulty and cognitive loading.It indicated that the MLD only had some advantage over MRD for they used more cognitive skills to solve the problem.

基于以上实验的结果，对两类数学困难小学生的应用题问题表征的认知机制作如下推断：混合型数学困难学生仅在高难度水平的应用题列式成绩和中高难度水平应用题问题表征水平上比单纯型数学困难学生得分显著低下，表明两类数学困难小学生在计算能力与理解简单题意的能力上并无差异，但随着难度提高，认知负荷加重，两类数学困难学生在应用题解题上的差异得以突显，表明当需要运用更多的认知能力解决问题时，单纯型数学困难学生比混合型困难学生更具优势。

The problem of finite precision multiuser decorrelator is formulated as linear bounded integer optimization problem,and the problem is shown to be NP-hard problem.

该文首先分析了应用有限精度序列为解相关矩阵序列的解相关接收机，将有限精度解相关的多用户检测问题归约为线性约束整数优化问题，同时证明此问题为NP-hard问题。

Based on Pontryagin maximum principle, the lunar soft landing problem is transformed into a two-point boundary value problem in mathematics. In consideration of the bound condition and transversality condition, the resulted two-point boundary value problem is converted into a parameter optimization problem aiming at the initial values of conjugate variables and the terminal time, then it is solved by the nonlinear programming.

首先，从庞德里亚金极大值原理出发，将有限推力作用下月球软着陆问题转化为数学上的两点边值问题；在考虑边界条件及横截条件的前提下，将该两点边值问题转化为针对共轭变量初值和末时刻的优化问题；然后应用非线性规划方法求解所形成的参数优化问题。

Moreover, if the optimization problem has certain special feature, the simpler relaxation methods can be provided. For example, considering a generalized geometric programming problem, relevant relaxation linear programming can be obtained using its special structure. Based on the branch and bound method, a linear relaxation algorithm of global optimization is presented for generalized geometric programming, and the convergence of the algorithm is also proven.

此外，当优化问题具有某种特殊性质时，我们能给出更加简便的松弛化方法，如考虑广义几何规划问题，能充分利用其特殊结构，建立了广义几何规划问题的松弛线性规划问题；在分枝定界技术的基础上，提出了一个求广义几何规划全局解的线性松弛算法；证明了算法的收敛性。

The membership function can exactly express the fuzzy satisfaction set by considering the vagueness of satisfaction degree of objectives and introducing the membership function for the fuzzy satisfaction sets of system reliability and system cost. The normal distribution and Cauchy distribution of this membership function is modified according to the fuzzy satisfaction sets. By doing this, the multi-objective optimization problem can be converted to a single-objective optimization problem to be solved.

模型充分考虑到目标满意度的模糊性，通过引入系统可靠度与费用的模糊满意集的隶属函数，并根据它们的模糊满意集对其正态分布、柯西分布进行适当修改，使之能够准确表达通常情况下的这两个目标的模糊满意集，最终，把两目标优化问题转化为常规单目标优化问题求解。

Effective local search tactics reaches local searchers when they are ready to buy - with every way that it is possible for them to buy from you.

有效的地方搜索策略达到当地的搜索，当他们准备购买-以各种方式，这是他们有可能从您那里进行购买。

The first two are periodic sentences for their beginnings; and the fifth and the last are also periodic sentences each for the embedding of a parenthetic structure.

1960年代中后期，当战后女权主义和当时的许多其他抗议运动在西欧和北美发展成某种势力时，性别的概念演绎成补充和延伸生物性别差异的概念。