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41.
The Lexicographic method has subjective and empirical character,so a weighting coefficient is introduced by considering the importance and proportion of each individual object,the preferable result of every individual object can be confirmed by comparing the degree of similarity between the perfect one and the ecumenic one and the Fuzzy optimization will be perfect.The effectiveness of these methods is illustrated by a fuzzy optimal design of the three-bar truss.  相似文献   
42.
以某钢厂四流中间包为研究对象,根据相似原理建立了1∶3的物理模型。模型研究了不同结构的挡墙、导流孔和湍流抑制器对中间包内流动特性的影响。实验结果表明,“Y”型挡墙和梯形湍流抑制器(方案F)组合的控流装置能获得相对较优的实验结果。采用方案F的控流装置后,总体的死区比例从原型的23.69%降为8.02%,钢液能得到更为充分的混匀;各流平均停留时间的标准差从原型方案的23.56降低到7.34,各流一致性也得到了明显的改善。  相似文献   
43.
The conjugate direction method for solving the unconstrained optimization problem is extended to solving the constrained optimization problem by method of differential geomtry.By inducing a new class of affine connections on a constrained sub-manifold, the primary constrched optilnhation problem is converted to a unconstrained local quadratic programming problem.Based on the definition and construction of a new class of generalized conjugate directions, it isproved that optimum value of the primary constrained optimization problem must be located on thegeodesic line which is formed by the conjugate directions mentioned above and can be reached withinfinite searching step. Therefore a new curve search algorithm with generalized conjugate directions isput forward.  相似文献   
44.
In combination with the migration of industrial projects to be in undated in thereservior area of The Three Gorges project, a level analysis apptoach is used to formulate a policy-making model of invest optimization for the projectS to be migrated,in which various kinds of influ-encial factor on the projects are presented quantitatively and the restriction of limited resourccs isconsidered; An effective,overall and aaplicablc policymaking approach is provided for the migrationof the Three Gorges project.  相似文献   
45.
This paper presents a reactive power optimization method which combines thelinear programming model with secure correction. In correction. this mOdel presents a new idea inwhich the feasible control region of con trol variables is resolved by over constrained state varlables. This method is quick and reliable and overcomes oscillation of a general linear programming model.  相似文献   
46.
In this paper, a new high - strength worm gearing, named'rolling cone enveloping hourglass worm gearing' is proposed. With such a new type of worm gearing, the motion form between meshing tooth surfaces is changed in nature. A systematic theoretical study. a lot of numerical calculations and parameter analyses have been done. Based on these analyses,the optimum design of worm gearing is obtained. It is shown that this worm gearing possesses the virtues of high efficiency, large load capacity, long life -span and easy meanufacture.  相似文献   
47.
A new trust region algorithm is proposed for solving unconstrained optimization problems. According to the quadratic approximate model of the original optimization problem,the trust region algorithm uses directions,a convex combination of the quasi-newton direction and the steepest descent direction. This algorithm with new strategy is analyzed and the global and local quadratic convergent theorems are proved. At last,the implementation and computational results of the algorithm are demonstrated.  相似文献   
48.
Based on alalysing the mathematical models for one dimensional equal stock cutting problem,a knapsack column generation algorithm has been constructed,which is a successive approximate algorithm for the practical engineering.In the end of this paper,some computational examples have been presented,which show that the convergence and optimum results of the algorithm are quite good.  相似文献   
49.
基于对目前产品平台设计的研究综述,分析并指出了研究中的不足。介绍了产品平台的概念和特征,探讨了基于公共平台的产品族设计方法。提出了基于主从关联结构的层次优化设计理念,以及实现这一理念的方法和模型框架:并对模型的数学形式、模糊层次优化做了阐述。  相似文献   
50.
An irrigation water management research programme was implemented by Hydraulics Research in collaboration with the National Irrigation Administration of the Philippines on the Porac Area of Porac Gumain Rivers Irrigation System. The objectives of the study are to monitor the response of the main canal network to changes in water availability and assess its capability to deliver crop water requirements to sub-areas jointly managed by National Irrigation Administration staff and existing Irrigator Associations. This paper presents an analysis of the response of the main system to the varying irrigation demands, and assesses the conjunctive use of groundwater with surface water and the potential of computer models to assist management with the preparation of the annual irrigation schedules.  相似文献   
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