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Zhang C.,CAS Institute of Policy and Management | Liu Y.,CAS Institute of Policy and Management | Qiao H.,National Research Institute for Rural Electrification
Physics and Chemistry of the Earth | Year: 2015

The relationship among the population, economy and water resources is complex, and the contradictions and conflicts will appear and aggravate with the rapid development of economy and society in Northeast China. Based on the statistical analysis of the available data, this paper depicted the static distribution characteristics of the population, economy and water resources of Northeast China in 2011. It was found that the spatial distribution of the population, economy and water resources was unbalanced in Northeast China. The water resources mismatched with the population and economy. The population and economy were relatively dense and developed in the southwestern part of Northeast China respectively, while the water resources was relatively scarce. However, the situations in the northern part of Northeast China were opposite to those in the southwestern part. The population-economy inconsistence indexes of the cities in northern part of Northeast China showed a significant trend of spatial aggregation and heterogeneity. The cities with lower (<1.5) and higher (>1) inconsistence indexes all faced the problem of water resources shortage. Applying geometric gravity center method and grey correlation model, the result indicated that there was relatively high spatial relevance and the relative deviation among the spatial dynamic distributions of the population, economy and water resources was large. The gravity centers of economy and per capita average annual total water resources moved westward, while the gravity center of population gravity center moved eastward in the period of 1997-2011 in Northeast China. It must be noted that, the migration trend of the economy gravity center was more significant than those of the population and water resources. © 2015 Elsevier Ltd. Source


Cheng X.,National Research Institute for Rural Electrification
Shuili Fadian Xuebao/Journal of Hydroelectric Engineering | Year: 2012

An extension model of regional river division is put forth to consider influences of technology, economy, zoology and so on, all of which are important factors in division of river carrying capacity. This model takes multi-index values as key decision factors, particularly for hydropower station in rural areas, and solves the conflict between technical exploiter and ecologic exploiter through extension transform and evaluation. Application to typical rivers in Zhejiang province is demonstrated. © right. Source


Cheng X.,National Research Institute for Rural Electrification
Shuili Fadian Xuebao/Journal of Hydroelectric Engineering | Year: 2013

Nowadays there exist many difficulties in national hydro-energy division. This paper designs and studies an evaluating decision support system for national hydro-energy resource division (NHRDS) to guide rational allocation and efficient use of hydro-energy. This system is based on J2EE development technology and an extension evaluation model, and it is equipped with three-dimensional properties of the role based access control (RBAC), river basin hydro-energy resources assessment function based on GIS, data mining function, and integration and intelligent reasoning functions of hydro-energy resources evaluation algorithm. The core technologies used for its design and development include hierarchical design techniques, AOP design, FSSH flexible architecture design technology and IoC (inversion of control technology). It has a good mechanism in security, augment ability, coupling and interactivity and can perform mass data mining and processing effectively. Pilot run results show that the system supports river basin hydro-energy resources division and intelligent decision for effective integration of river basin development and thus it lays a basis for further development toward nationwide application. © Copyright. Source


Xu Y.,China Institute of Technology | Zhang R.,China Institute of Technology | Zhang R.,China University of Technology | Cheng X.,National Research Institute for Rural Electrification
Shuili Fadian Xuebao/Journal of Hydroelectric Engineering | Year: 2014

Considering the shortage of real machine test data in design of pump-turbine for most of the pumped storage power stations in China, this paper presents a study of plant optimal operation and joint economic operation of hydropower and thermal power stations based on model test data of pump turbine, design data of pipe system, and efficiency characteristic curve of generator provided by the manufacturer to enhance the dynamic benefits of pumped storage stations. First, data of fuzzy dynamic characteristics were measured and a point-to-point modification on fixed dynamic characteristics of fuzzy data was made with an "exponential decay" static method in combination with the historical databases recorded by the computer monitoring system of pump-storage station. Then, the data of dynamic characteristics were corrected dynamically via an extension neural network training method based on a principle called "disjoint and linear equidistant head of unit". These two methods were coded in integrated modules that are embedded in a software system. Thus we have developed the system V3.0 for analysis of the dynamic characteristics of pump-turbine in pumped storage power station. Application shows that the characteristic equations of pump-storage station derived using the previously-mentioned modification and correction better describe the real cases and their solution produces satisfactory results. The present work would lay a basis for further study on plant optimization of pump-storage station and economic operation of joint hydro-thermal power stations. ©, 2014, Tsinghua University Press. All right reserved. Source


Mao J.,China Institute of Technology | Zhang R.,China Institute of Technology | Zhang R.,Zhejiang University of Technology | Wang W.,Zhejiang University of Technology | Cheng X.,National Research Institute for Rural Electrification
Shuili Fadian Xuebao/Journal of Hydroelectric Engineering | Year: 2015

Some large and medium-sized irrigation water pumps in China have run for a long time, and their existing dynamic characteristics are significantly different from the design conditions. To obtain more accurate dynamic characteristics of these pumps, first we obtained the raw data of dynamic characteristics from the raw material of pump source, design data, and efficiency curve of the motor, etc. Second, the dynamic characteristics were corrected using a static correction method of exponential decay and a dynamic training method of the extension neural network in combination with the measurements of pump sets in practical operation. Finally, we developed a large and medium-sized irrigation pumps dynamic characteristics analysis code V3.0 that integrates the two methods into a single module. Practical application shows that the modified equation of pump power characteristics that is used in this code, can describe the real engineering conditions. And typical characteristic curves produced by the code have a reasonable spacing and follow the same trend without intersecting. The data fitting errors of the code are low and the actual results of the code applications are satisfactory. This study would lay a basis for further study on the optimization of joint operation of the pumps and the gates. © All right reserved. Source

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