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51.
海河二道闸和防潮闸优化调度研究 总被引:1,自引:0,他引:1
汛期为腾空海河河道并保证二道闸下咸水不致上溯,二道闸闸下水位应控制在1.0m左右。利用一维非恒定流模型对海河自西河闸至入海口河段进行数值模拟,研究了西河闸分流量为80、100、120m3/s3种情况下,海河防潮闸和二道闸优化调度结果。 相似文献
52.
According to the new requirement of sustainable development in the new stage, this paper puts forward the definition of the safeguarding capacity of regional sustainable development and uses some statistical methods of frequency statistics and principal component analysis to construct the index system of safeguarding capacity. Then it takes the data of the Three Gorges reservoir area for example to make empirical analysis, and provides efficient measurement tools to further measure the regional sustainability together with its safeguarding capacity, and therefore helps the government and the relevant organizations to establish more scientific policies of sustainable development. 相似文献
53.
54.
FENG Wei-min~ 《保鲜与加工》2004,(6):103-108
The society-economy-environment appraisal for construction project can help our government to control macro-economy, make correlation policy and formulate laws and draw up city plan.It has great influence on the sustainable development of our society and it is the demand of the law for the environment evaluation in China.This paper introduced the basic structure of society-economy-environment appraisal system for construction project and the thought of elements transaction.Using the method of AHP, the model of project analyzing and optimizing selection is designed.For the more, the methods of the optimizing models on the selected schemes are put forward.Finally, the integrative analysis has been made on the system design and appliance of this appraisal system. 相似文献
55.
:In
accordance with the problems, occurred in the mountainous city's construction, especially
the crises such as the destruction of ecological and humanistic environment, the loss of
traditional culture and characteristics and the disorder of urban structure, this paper
discusses the distinctive landscape characteristic of mountainous city thoroughly. 相似文献
56.
Chang Baobo Sun Hongbo 《保鲜与加工》1997,(6):16-22
This paper has applied the var cost to the theory of spot price.An augmented Lagrange method is employed to develop the exact model of spot price of active power and reactive power,and the physical means of Lagrange multipliers are explained.The numerical examples are given to demonstrate the validity of the proposed model. 相似文献
57.
Aimed at soving the problem existing in the knowledge-acquisition directing-operation expert systems, a new method is proposed to acquire knowledge of expert-operation, excluding errors existed in examples and reinforce the accuracy of examples,the goal of knowledge acquisition can be achieved, the method presented in this paper solves the problem of self-enhancement of expert knowledge on line efficiently. 相似文献
58.
As a product of work division and cooperation in construction industry,the construction supervision has contributed actively to China's construction.As the international and home situations have changed,a higher requirement has been put for China's construction supervision sector.Based on the principles of generalization and comparison this paper studies and discusses the existed problems on sustainable development of construction supervision sector in the ideological recognition,the theoretical study,the administrative system,the code building and the practical manipulation,etc.and corresponding suggestions are given on this basis. 相似文献
59.
In the general directing-operation expert systems.the information of directingoperation is often shown after the subprocess has finished,The aim of the thesis is to enhance thefunction of directing-operation,and suggest that we add the self-tuning predictor in the expertsystems and use it to direct the present operation.We have shown the case oftemperature-predicting experiment made in the small wine distillatorv so that we can illustrate thatit is feasible to use the predictor to direct the operation. 相似文献
60.
Urbanization in China is at an essential point in its transformation from the initial stage to accelerating stage. With quick expansion of city scale and large occupation of land for urban construction, the contradiction between land resource shortage and people's living needs becomes more and more prominent. It has great affection on the grand plan of China's sustainable development of economy and society. How to adjust the relations between the development of urban construction and protect the land resource, promote the rational use of urban land, perfect and complete the protection system of land resource for improving the efficiency of urban land use. In order to conserve land resource and find a sustainable way for development of people's living and environment construction, the above mentioned problems are the most important issue for urban construction and important subject of this paper. 相似文献