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991.
This paper presents a new practical criterion for voltage stability based on the real-time information at the substation and the quasi-time information from power system.By using the criterion,it is effective to predict the bus voltage stability margin.This is of great importance to raise the security operation level and prevent voltage collapse.The practical criterion for voltage stability is tested on the IEEE-14-bus test system.It needs less calculation time and is very suitable for real-time control of power systems. 相似文献
992.
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
993.
This paper presents the lately released frame work for Client / Server applica-tions software development, stressing on the characteristics of its OOP and Multi-DataBase supports. 相似文献
994.
995.
In this paper,the electrical field distribution along the polluted cylindrical insu-lator before a nd after the local a re appea rs is calculated with the optim lzed pa rtially cha rge simula-tinn method and measured with the pockels device. Based on the calculating and measuring results,the in fluen ce of the electric field distri bu tion on the propagation of local a re in the flashover ofcyIlndrical insufator under various conditions is analyzed systematieally. 相似文献
996.
Dai Dayu Xu Mingxi Peng Qingchu 《保鲜与加工》1993,(3):99-103
The status quo of heauy-metals pollution in water phase of course of Long-Tan hydropower statian was eualuated by water Quality Standand Level Method. With this special method,mone objectiue and definite results were obtained. 相似文献
997.
Sun Hongbo Xu Guoyu Qin Yihong 《保鲜与加工》1992,(4):80-86
This paper proposes a multi - objective fuzzy decision - making approach for power network planning under uncertainty ,which simutaneously considers not only the least investment cost,the minimum power loss,the maximum reliability,and the least environmental impacts, but also the uncertainty about the future load growth and the capital investment availability. The validity and effectiveness of the proposed approach is verified with numerical examples. 相似文献
998.
999.
Gong Jian Liu Fei Xu Zhongjun 《保鲜与加工》1997,(1):92-97
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
1000.
本文对不同类型小麦品种（系）的11个与产量密切相关的农艺性状,生理指标进行了主成分分析。11个原始指标综合成为三个独立的新指标,分别表示“光合同化因子”、“库与碳氮代谢因子”、“库与氮素营养因子”。主成分值与产量相关分析表明,小麦产量与第一、第二主成分值有极显著正相关关系。通过回归分析,建立了小麦产量与主成分值之间的回归方程。它能较好地反映不同类型品种的产量水平。 相似文献