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981.
The feasible control problem is presented for the day-operation of the Three-Gorge Caseade Hydropower Station. The significance of the problem is explained. Basic propetties ofthe problem and the approaches to study it are discussed. Two methfods are given for solving theproblem. which are calculus of variation and linear programming. In the former. the Euler equationwith time-lag and the generalised two-point boundary conditions are obtained and the correspondingpractical implication is interpreted. In the latter. the rationality for the discrete model is exptainedand the computalional details are given for the implement software. some questions which should bepaid much attentfon and the corresponding propeels are prasented based on the numerical results andtheoretical analysis  相似文献   
982.
面对全球、我国和我省种子产业的发展趋势,分析了我国高校近年来建立种子学科的现状和广东有关高校种子学科建设的可能性,提出了一些仅供参考的设想.  相似文献   
983.
Gymnasium in Harbin Normal University Sports Center is a large-scale gymnasium. This paper analyzes unfavorable factors in its acoustics and illustrates different kinds of intention of the design. At the same time, the questions about the project operation and technique are pondered one by one, it is expected that these thinking can provide some experience to the similar project.  相似文献   
984.
985.
This paper analyzes the current situation of university students' credit evaluation and set up an evaluation index system of university students' credit to compensate a loan.Based on this index system,this paper sets up a matter-element evaluation model on the individual credit of university students loan by means of extensible engineering method.The grade of individual credit and the index for evaluating the level of individual credit are made as matter-element,meanwhile,the classical field,the segment field,the weight coefficient are obtained.Dependence function is established based on the grade of individual credit and then the grade is judged by calculating the synthetic dependence degree.Finally,this paper presents the evaluation method by giving an example.This method is simple in calculation,reasonable in evaluation with high applicability.  相似文献   
986.
Along with the establishment of the constructor association,how to locate the constructor association is extremely important at present,which is not only related to the efficiency of the constructor trade management,but also related to the future development of the constructor trade.This paper launches the discussion on the constructor association's localization from three aspects,namely the legal localization,the profession localization and the relation localization with the government and its members,and puts forward some proposals and individual opinions.  相似文献   
987.
MA Li  TANG Qi 《保鲜与加工》2002,(2):124-127
According to the present research situation of conductive polymer materials- polyaniline (PAN) ,we reviewed the structure and properties of PAN, the effecting factors and the best conditions of electrochemical synthesis and chemical synthesis of PAN , the doping mechanism of PAN, inorganic and organic acid doping,secondary doping, the method of increase soublity and processability of PAN and the broad application of PAN. The development derection and prospect of PAN are pointed out.  相似文献   
988.
The preparation method of transparent film of electrochromism polyaniline on the glass supporter is studied by a dipping polymerization. The electric and optic properities of the resulting film are measured as a function of oxidant,dopant,reaction time and temperature.The optimum technology term is obtained in the normal atmospheric temperature.The experimental result is testified by fuzzy set theory.  相似文献   
989.
The policy of public participation in urban planning was first practiced in Europe in the 1960s. After 40 years of development, the policy has become the essential step of city planning in Western countries where as is just at the elementary step in China. For the purpose of knowing the situation about the policy performing in local cities and discussing the feasibility of public participation in urban planning, several kinds of investigation have been done. From the investigation, it is found that although the public participation has already been the important step of urban planning in some city during just several years,there are still many problems. This paper shows a panorama view of this issue. Th describe the future of public participation in e authors will offer some solutions according to the problems and the urban planning.  相似文献   
990.
Voltage fluctuation and flicker is one of the main causation that imperils reliability of power supply. Steelmaking EAF with large load of distribution network produces large impact and interference on the public electric network in operation. So it is very important to control reactive power for voltage fluctuation and flicker mitigation. STATCOM possessing high response speed is an effective measure to mitigate voltage fluctuation and flicker of distribution network. Here, comparing to static var compensation, many advantages of STATCOM are analyzed. Operation principles COM mitigating voltage fluctuation and flicker, general control strategies and control method are introduced cussed. The researching pivot and trend in the future are also discussed. of STAT- and discussed. The researching pivot and trend in the future are also discussed.  相似文献   
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