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61.
In urban design, only by continuous and dynamic research work from design to finally putting it into practice, can we made good control on city appearance. This article analyzes nowadays defects in our urban design from two aspects as the result establishment and validated control, and tries to conceive a feasibility plan to solve the problem. 相似文献
62.
TAN Wen-an 《保鲜与加工》2004,(12):73-77
By analyzing the process of enterprise information engineering construction and intra relationship among information system requirement, business process modeling, application system constructing and project management, one of 4 meta model composed of requirement engineering, process engineering, application system engineering and support engineering is proposed for enterprise information engineering. The developments and applications of the business processes and its application systems are integrated into the same development space and application space. Basing on this, a prototype system composed of requirement modeling environment, business process modeling environment, application system modeling environment, and support engineering environment has been designed and built, which is used for supporting enterprise information engineering constructing. It is valued for the enterprise information engineering construction in our country. 相似文献
63.
In this paper the test results of mixed mode fracture of three kinds of brittle rock under two kinds of stress paths are reported. The fracture mechanism and failure patterns of brittle lock under different stress paths are discussed. Theory analysis and test results show that the Compression- Shear fracture criterion of brittle rock can be expressed: 相似文献
64.
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
65.
Liu Chongde Wang Xiaoming Gu Lan 《保鲜与加工》1992,(6):10-17
A optimal design with whole structure parameters and its program are carried out. A reasonable model is established. Using the method a optimal design with whole structure parameters by original parameters of American P&H2300xp excavator was calculated. The size,carried out by the method,approximates to the size of P&H2300xp excavator very well. 相似文献
66.
Zheng Xiaoqing 《保鲜与加工》1995,(4):9-17
In view of the complication of compreliensive evaluation to development projectplanning alternatives,an AHP model for comprehensive evaluation to the alternatives is advanced,the way of determinating the weight of each index affecting the aIternatives' quality is expounded,and the general methods of evaluating the alternatives with the indexes are given. 相似文献
67.
Based on the analysis of the status of building construction in China, the development of Assembled Structure System (ASS) can solve not only the problems in construction, but also is the key for realization of building industrialization. On the basis of technique innovations, a study on the structural performance, construction method and precast production of ASS should be carried out to inherit the old one and overcome its demerits. The process reengineering should be done in the construction enterprise to promote the development of building industrialization. 相似文献
68.
Condition assessment on power transformer is an important approach to improve reliability of transformer and provide proper decision-making for condition-based maintenance. For long, static assessment method used in the past has already not adapted to the development of modem electricity transmission and distribution technology. So based on the deficiency of fuzzy synthetic assessment method, matter-element synthetic assessment method is introduced. The method can evaluate transformer condition not only in quality but also in quantity. Because each index weight can be given fairly and fast through improved analytic hierarchy process, which need not carry on consistency chec accuracy of assessment can be improved. Examples analysis has proved that assessment method of power transformer condition based on matter-element theory is rational and effective. 相似文献
69.
70.
This paper takes "how to estimate the complex security of Large Convention and Exhibition Centre effectively" as the research goal.Based on analyzing the difficulties,target system,technical constitution,probing into the architecture,safety science,and using for reference the mathematics,operational research,statistics and modern system theory and method,trying to explore establishing an evaluation methodological system,which is provided with integrated characters on subject.Based on these ways,it exerts "quality to quantity" fuzzy analytical hierarchy process(FAHP) and aims at discussing the safety grade assessment of the Chongqing International Conference Exhibition Center focusing on designing theories.The aim is to enhance the integration of design practice and safe consciousness,strengthen the building safety management,and perfect city public security system.In practice,it is also an efficient tool for favoring values of architectural environmental safety. 相似文献