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911.
Liu Haijun Deng Renming 《保鲜与加工》1992,(5):51-56
This paper presents a new hierarchical and coordinative control method for reactive power optimization in large-scale interconnected power systems. It combines the interconnection forecast method for hierarchical control in large-scale steady state industrial systems with the incremental linear programming method for reactive power optimization in real time. The results of applying the method to power system examples show that the method not only solves the problem of high dimension in order, but also keeps the advantages of the incremental linear programming method. The proposed method is also suitable for the security analysis of reactive power correction in large-scale interconnected power systems. 相似文献
912.
With the strengthening of constitutional protection that legal private property is not to be encroached upon and the land usufructs paid regime are further clear, the regime of urban housing dismantling and moving is facing a vigorous test. This paper analyzes three problems: the justice of the withdrawal of land use right, the legality of the alteration of the land use right and the rationality of the compensation of the land use right during the urban housing dismantling and moving. Finally, this paper tries to find some effective measures to solve the chain problems. 相似文献
913.
Application system generally refers to all kinds of computer information system. It aims at improving the sharing and application of the resource. The resource in application system usually means data resource. For computer management and maintenance, there are not only data resource, but also program resource and network resource. Effective management of this resource is key to ensure proper work of the application system. In this paper, the basic pattern and policy for resource management is put forward and a method to build and realize the resource layer that lies between database layer and application layer is to be found. This management layer, which skillfully connects the application system with resource and establishes good base for application and exploitation of system, is named as resource management system. 相似文献
914.
The conservation of historic buildings and their environment is an unavoidable problem in urban construction. In this paper, the authors give a few new thoughts about the problem. First, the historic buildings are important part of the core power in city competition.Second,the conservation work should be combined with their development. Third, a classified and multilevel system of protection and reuse of old buildings should be set up. 相似文献
915.
This paper is a part of the research on the lighting techniques of the traditional Chinese buildings in Summer Palace,Beijing,which is a sub-project of the Municipal Research Project on the Correlative Techniques for Beijing's Sustainable Development(Y0604017040391).The work,which the authors took part in,on the most representative Chinese traditional buildings in Summer Palace,is taken as a case study on lighting design and lab simulated experiments and checked by practical result,illustrating a working frame for other similar lighting design works. 相似文献
916.
917.
The deformation characteristics and the plastic-loop of the fine-sandstone is studied under the loading and(unloading) condition at the three different deformation-rates and the two different stress-levels,the results show: 1) There is really the plastic-loop in the deformation curve for the loading deformation curve is different form the unloading deformation curve.But the plastic-loop is nearly unchangeable since the second circulate loading.2) There is different for every imitational parameter between the first deformation curve and the second deformation curve at the different stress-levels and the different deformation-rates,but every imitational parameters become more and more invariable gradually since the second circulate curve.3) With the change of the deformation-rates and stress-levels,the imitational(parameters) will change with it.4) The imitational parameters are different for loading section and unloading section of the fine-sandstone deformation curve at the same circulate curve under the same deformation-rate and stress-level. 相似文献
918.
According to the graphics characteristics of metallic doors & windows design and based on the research of graphics dimension restriction problems. This paper provides a new method for parameterized design of metallic doors & windows in virtue of expression solution. In this method, the restrictions of graphic elements have been changed into the parameter expressions of sizes and positions of graphic elements. Through the calculation of such expressions, the parameter driven method has been reached. Thus the parameterization of graphics can be easier and quicker than before. It can be used to setup the open parameterized graphics libraries. 相似文献
919.
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
920.
Valuation based on the bill of quantifies will change the existing valuation mode of tender and bidding. For the standardized management of tender and bidding for power projects and the inteUigentized information management of power enterprises, it is an inevitable trend of reform to apply the valuation mode based on the bill of quantifies. According to the characteristics of power projects, this paper expounds the working process of the valuation mode based on the bill of quantities and analyzes the goal and function need of the tender and bidding management system. Considering the calculation procedure of the valuation and the quote strategy of quantities bill, the composition of fees for the valuation is settled and the calculation method is designed. To establish the management system of tender and bidding with a valuation based on the bill of quantities is beneficial for the costing reform of power projects and the perfection of the tender and bidding market. Therefore it is of great significance to spread the new management mode of project costing with a valuation based on the bill of quantities. 相似文献