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111.
Characteristics of a tire are the foundation of vehicle dynamics studying, especially play a vital role in vehicle handling study. It is necessary to establish a tire model in the simulation for vehicle handling because the tire characteristics got by test can not be satisfied.The optimization of fitting to the tire test data curves by Magic Formula is discussed, included the digitalization of tire test data curves, designing objective functions and optimization processes,etc. Finally the parameters in Magic Formula tire model are obtained and they lay a foundation for the development of vehicle handling aftertime.  相似文献   
112.
Bomsster is a key load-bearing part of railway lorry bogie.Because of its inherent defects casting-steel bomsster could not meet the demands of the heavy load,acceleration and security for lorry.So forging process is proposed to form it.The forming performance of forging-steel bomsster is analyzed.A forging technology is presented which realizes two forging-steel bomsster parts formed in one die.With the plastic forming simulation software DEFORM-3D,the simulation and optimization of the forming process of forging bomsster has been taken based on 3D rigid visco-plastic FEM theory.Optimized scheme has been used to direct the pilot product.The results of product's testing and application suggest that the new forging technology is feasible and the performance of the product is credibility and stabilization.The factory has realized large scale production of a series of forging-steel bomsster.Remarkable benefits of both economy and society have been achieved.  相似文献   
113.
This paper investigates the coordinated operation of the progress planning with the resource planning when carrying out engineering projects and puts forward a method of "RSM" under the resource limit conditions. Then, the "RSM" was improved to avoid complicated calculation. This method not only reduces the calculating work by hand but saves computer's memory as well, making the time-resource optimization work more quick and convenient.  相似文献   
114.
Through the analysis in this paper,the optimum relation of the discharging current peak interval t m ,the discharging loop equivalent inductance L and equivalent resistance R is obtained.This paper analyze the original discharging loop equivalent inductance L ,which provides an effective method for adjustment and selection of inductance L to realize the optimization energy saving design of the welding machine.  相似文献   
115.
An optimization approach for multi-relational joins based on the matching concept in graph theory is introduced. The basic idea lies in constructing a join graph from an expression of N-relation query, and seeking for a maximun matching with minimun total weight. The algorithm for bipartition(X, Y) is proposed in this paper.  相似文献   
116.
Based on the analysis and study on some existed models for two-dimensional Guillotine Cutting-Stock problem, it is pointed out that some kinds of the models may miss some good cutting patterns,and some may result in inadequate solutions because of only considering the patterns with the smallest waste. A kind of revised two-dimensional cutting-stock models are developed,which transform the two-dimensional problem into the one-dimensional one using the dimension-decreasing heuristic method and whose initial patterns are considered comprehensively. In this kind of models, not only the least waste,but also the other constraints,such as the demands and the relative area of the order plates are considered.  相似文献   
117.
A structural optimization algorithm is performed for single-layer Kiewit reticulated dome by means of ANASYS. In the process of optimum design, the overall weight is taken as objective function; the stress constraints and stability constraints etc are considered. Meanwhile, the geometrical non-linearity is taken into account. Then the overall stability analysis for the optimized single-layer reticulated dome is operated. The results show that the optimization design is reliable.  相似文献   
118.
In this paper, based on the discussion of orthogonal decomposition method for the buckling mode of unsymmetrical structure, taking the variable-section beam-column as an example, a simple and direct method of the second order analysis is presented. In the new method, the conception of enlargement coefficient brought forward by Timoshenko is developed. To begin with the curvature of the variable-section beam-column, the linear equations are set up. With their solution, a group of orthogonal buckling mode can be obtained. The primary deflection can be decomposed to a group of homomorphic deflection similar to buckling mode. Then, the group of deflection is multiplied by corresponding enlargement coefficient and plus the result, finally, the second-order total deflection can be obtained.  相似文献   
119.
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   
120.
A nonlinear finite element analysis of 4 RC deep flexural simply supported beams with the program VT2 is presented. Crack development and failure modes , longitudinal reinforcement strain distributions and load -deflection curves were compared as a result in order to evaluate the validity of the disturbed stress field model to analyse such deep simply supported beam.  相似文献   
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