查询词典 combinatorial optimization problem

The gradient projection method is a class of effective algorithms for constrained optimization problem,and it has an important position in optimization.

梯度投影法是一类有效的约束最优化算法，在最优化领域中占有重要的地位。

In this dissertation, incorporating the level set algorithm, the gradient projection method, the nonlinear mapping technique, the return mapping algorithm and the mean curvature flow technique into topological optimization theory, a level set algorithm for topology optimization with multi-material structures is put forward, which can optimize a problem with general objective functions, multi-constraints, multi-materials and multi-load cases.

同时，又将拓扑导数理论和水平集算法结合起来，提出了结构拓扑优化的拓扑导数与水平集算法，进一步提高了计算效率。

In the other hands, we present a levelvalue estimation method for solving global optimization. The global optimization problem will be converted into solve the first root of a nonlinear equation.

此外，我们提出了求解总极值问题的水平值估计方法，将一全局优化问题转化为求解一元非线性函数方程的根。

The existence theorem of generalized weak efficient solutions with respect to variable, cone for a linear G〓teaux differentiable mapping is proved with set valued mapping fixed-point theorem and the relation between a vector optimization and a variational inequality problem. The existence of weak efficient solutions for multi-objective convex vector optimization is characterized.

建立映射在线性G〓teaux可微条件下关于可变锥的广义弱有效解的存在性及多目标凸向量优化问题在G〓teaux可微条件下弱有效解的特征，利用集值映射不动点定理及向量优化与变分不等式的关系证明线性G〓teaux可微锥凸映射关于可变锥的广义弱有效解的存在性定理。

In order to optimize tolerance values for an assembly system, a model for geometric dimension tolerance optimization was established and an algorithm for optimal tolerance design was proposed. The algorithm is divided into two stages: at the first stage, design centering problem is solved and statistical optimization for further lowing the cost is solved at the second stage.

为优化装配系统中公差链的公差值，建立了几何尺寸公差的优化模型，并提出公差的分层优化设计算法：第一层，解决设计公称值居中的优化问题；第二层，解决进一步降低成本的概率性优化问题。

A necessary and sufficient condition for the existence of guaranteed cost control is derived. Furthermore, it is shown that this condition is equivalent to the solvability of a system of linear matrix inequalities, and its solution provides a parameterized representation of guaranteed cost controllers. Based on that, the design of the optimal guaranteed cost controller is formulated as a convex optimization problem, which can be solved by the existing convex optimization techniques.

通过采用线性矩阵不等式的方法，导出了存在保性能控制律的一个充要条件，进而，证明了该条件等价於一组线性矩阵不等式的可解性问题，并用这组线性矩阵不等式的可行解给出了保性能控制律的一个参数化表示。

Because the Gibbs free energy function has multiple minima caused by the strong nonideality and the optimization problem always has a tiresome trivial solution, local optimization algorithm will not converge to global minimum in general, which leads to wrong judgment for phase stability.

对于强非理想体系，或在高压条件下，其TPDF表现出复杂形态，有平凡解和多极值，传统方法难以求得满足约束的全局最小值，从而导致判别失误。

For solving Multi-objective and multi-restriction optimization problem , this paper used non-dominated ranking method, elitist preserve strategy, niche approaches, and presented an individual vector module adaptive function as wash out rule, then an improved Pareto multi-objective optimization with genetic algorithm was found.

为解决含多个目标和多约束的优化问题，本文结合了非支配排序思想、精英保留策略，小生境技术，并对传统的小生境技术中基于个体适应度的淘汰技术进行改进，提出了一种向量模适应度函数来作为淘汰准则，得到一种改进的Pareto遗传多目标优化算法。

Finally a comparison of optimization results between complex method and genetic algorithm is carried out, which shows the value of objective function ha s decreased 6.6% under GA. This will help decrease the slippage of steering whee l and wear extent of tyre. At the same time, it also verifies the feasibility an d superiority of genetic algorithm in solving the nonlinear optimization problem s with many restraints and variables.

计算结果表明：与复合形法相比，遗传算法使目标函数值减少了6.6%，取得了较好的优化效果，从而更有利于减小转向车轮的滑移量和轮胎的磨损量，同时也验证了遗传算法解决多约束、多变量类型优化问题的可行性和优越性。

In allusion to the NP complete problem of multi objective optimization of QoS routing, the purpose of this paper is to find the most optimum solution of the routing optimization in a sense of Grey fuzzy within multinominal time.

针对QoS路由多目标优化的NPC问题，希望在多项式时间内找到QoS路由多目标优化在灰色模糊意义下的最优解。

We have something to do in the new stage.

在这段崭新的时期中，我们有一些要做的。

The difference between tourism decision-making under uncertainty and risky tourism decision-making is indistinctive.

其中不确定性旅游决策和风险旅游决策的界线比较模糊，两者的区分是相对的。