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Anti-interference beam pattern design based on second-order cone programming optimization 被引量:1
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作者 戴文舒 鲍凯凯 +1 位作者 王萍 王黎明 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2016年第3期255-260,共6页
When signal-to-interference ratio is low, the energy of strong interference leaked from the side lobe of beam pattern will infect the detection of weak target. Therefore, the beam pattern needs to be op... When signal-to-interference ratio is low, the energy of strong interference leaked from the side lobe of beam pattern will infect the detection of weak target. Therefore, the beam pattern needs to be optimized. The existing Dolph-Chebyshev weighting method can get the lowest side lobe level under given main lobe width, but for the other non-uniform circular array and nonlinear array, the low side lobe pattern needs to be designed specially. The second order cone programming optimization (SOCP) algorithm proposed in the paper transforms the optimization of the beam pattern into a standard convex optimization problem. Thus there is a paradigm to follow for any array formation, which not only achieves the purpose of Dolph-Chebyshev weighting, but also solves the problem of the increased side lobe when the signal is at end fire direction The simulation proves that the SOCP algorithm can detect the weak target better than the conventional beam forming. 展开更多
关键词 anti-interference beam pattern second-order cone programming optimization (SOCP) weak signal detection
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New optimized flux difference schemes for improving high-order weighted compact nonlinear scheme with applications 被引量:2
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作者 Shichao ZHENG Xiaogang DENG Dongfang WANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2021年第3期405-424,共20页
To improve the spectral characteristics of the high-order weighted compact nonlinear scheme(WCNS),optimized flux difference schemes are proposed.The disadvantages in previous optimization routines,i.e.,reducing formal... To improve the spectral characteristics of the high-order weighted compact nonlinear scheme(WCNS),optimized flux difference schemes are proposed.The disadvantages in previous optimization routines,i.e.,reducing formal orders,or extending stencil widths,are avoided in the new optimized schemes by utilizing fluxes from both cell-edges and cell-nodes.Optimizations are implemented with Fourier analysis for linear schemes and the approximate dispersion relation(ADR)for nonlinear schemes.Classical difference schemes are restored near discontinuities to suppress numerical oscillations with use of a shock sensor based on smoothness indicators.The results of several benchmark numerical tests indicate that the new optimized difference schemes outperform the classical schemes,in terms of accuracy and resolution for smooth wave and vortex,especially for long-time simulations.Using optimized schemes increases the total CPU time by less than 4%. 展开更多
关键词 optimization flux difference weighted compact nonlinear scheme(WCNS) resolution spectral error
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Optimized finite difference iterative scheme based on POD technique for 2D viscoelastic wave equation 被引量:1
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作者 Hong XIA Zhendong LUO 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2017年第12期1721-1732,共12页
This study develops an optimized finite difference iterative (OFDI) scheme for the two-dimensional (2D) viscoelastic wave equation. The OFDI scheme is obtained using a proper orthogonal decomposition (POD) metho... This study develops an optimized finite difference iterative (OFDI) scheme for the two-dimensional (2D) viscoelastic wave equation. The OFDI scheme is obtained using a proper orthogonal decomposition (POD) method. It has sufficiently high accuracy with very few unknowns for the 2D viscoelastic wave equation. Existence, stability, and convergence of the OFDI solutions are analyzed. Numerical simulations verify efficiency and feasibility of the proposed scheme. 展开更多
关键词 optimized finite difference iterative (OFDI) scheme viscoelastic wave equation proper orthogonal decomposition (POD) EXISTENCE STABILITY CONVERGENCE numericalsimulation
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Optimized Reimbursement Scheme of China's New Cooperative Medical System Using Monte Carlo Simulation 被引量:2
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作者 MENG Xue Hui HUANG Yi Xiang +1 位作者 RAO Dong Ping LIU Qing 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2013年第11期937-943,共7页
China's Rural Cooperative Medical System collapsed alongside communal farming at the end of the Maoist period in 1976, leaving most farmers vulnerable[1]. In rural areas, where 80% of people have been without health ... China's Rural Cooperative Medical System collapsed alongside communal farming at the end of the Maoist period in 1976, leaving most farmers vulnerable[1]. In rural areas, where 80% of people have been without health insurance of any kind, illness has emerged as a leading cause of poverty[24]. To address the poor state of health care among the rural population, in 2003 the Chinese government launched the New Rural Cooperative Medical System (NCMS), 展开更多
关键词 optimized Reimbursement scheme of China’s New Cooperative Medical System Using Monte Carlo Simulation
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Optimization of stratification scheme for a fishery-independent survey with multiple objectives 被引量:26
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作者 XU Binduo REN Yiping +3 位作者 CHEN Yong XUE Ying ZHANG Chongliang WAN Rong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第12期154-169,共16页
Fishery-independent surveys are often used for collecting high quality biological and ecological data to support fisheries management. A careful optimization of fishery-independent survey design is necessary to improv... Fishery-independent surveys are often used for collecting high quality biological and ecological data to support fisheries management. A careful optimization of fishery-independent survey design is necessary to improve the precision of survey estimates with cost-effective sampling efforts. We developed a simulation approach to evaluate and optimize the stratification scheme for a fishery-independent survey with multiple goals including estimation of abundance indices of individual species and species diversity indices. We compared the performances of the sampling designs with different stratification schemes for different goals over different months. Gains in precision of survey estimates from the stratification schemes were acquired compared to simple random sampling design for most indices. The stratification scheme with five strata performed the best. This study showed that the loss of precision of survey estimates due to the reduction of sampling efforts could be compensated by improved stratification schemes, which would reduce the cost and negative impacts of survey trawling on those species with low abundance in the fishery-independent survey. This study also suggests that optimization of a survey design differed with different survey objectives. A post-survey analysis can improve the stratification scheme of fishery-independent survey designs. 展开更多
关键词 fishery-independent survey optimization stratified random sampling stratification scheme computer simulation
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Modeling and Optimization of Ethane Steam Cracking Process in An Industrial Tubular Reactor with Improved Reaction Scheme 被引量:3
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作者 Mohsin Ali Liao Zuwei +4 位作者 Yao Yang Sun Jingyuan Jiang Binbo Wang Jingdai Yang Yongrong 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2020年第4期117-125,共9页
Ethane steam cracking process in an industrial reactor was investigated.An one-demsional(1D)steady-state model was developed firstly by using an improved molecular reaction scheme and was then simulated in Aspen Plus.... Ethane steam cracking process in an industrial reactor was investigated.An one-demsional(1D)steady-state model was developed firstly by using an improved molecular reaction scheme and was then simulated in Aspen Plus.A comparison of model results with industrial data and previously reported results showed that the model can predict the process kinetics more accurately.In addition,the validated model was used to study the effects of different process variables,including coil outlet temperature(COT),steam-to-ethane ratio and residence time on ethane conversion,ethylene selectivity,products yields,and coking rate.Finally,steady-state optimization was conducted to the operation of industrial reactor.The COT and steam-to-ethane ratio were taken as decision variables to maximize the annual operational profit. 展开更多
关键词 ethane steam cracking tubular reactor Aspen Plus molecular reaction scheme process simulation process optimization
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A Distributed Optimal Scheme Based on Local QoS for Web Service Composition 被引量:2
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作者 DAI Huijun QU Hua +2 位作者 ZHAO Jihong DONG Wenhan XIE Wujie 《China Communications》 SCIE CSCD 2014年第A01期142-147,共6页
The goal of web service composition is to choose an optimal scheme according to Quantity of Service (QoS) which selects instances in a distributed network. The networks are clustered with some web services such as o... The goal of web service composition is to choose an optimal scheme according to Quantity of Service (QoS) which selects instances in a distributed network. The networks are clustered with some web services such as ontologies, algorithms and rule engines with similar function and interfaces. In this scheme, web services acted as candidate service construct a distributed model which can't obtain the global services' information. The model is utilized to choose instances according to local QoS information in the progress of service composition. Some QoS matrixes are used to record and compare the instance paths and then choose a better one. Simulation result has proven that our ~pproach has a tradeoff between efficiency and ~quality. 展开更多
关键词 local QoS service composition distributed optimal scheme instance path
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Comparison of Optimization Schemes for the Flue Gas Purification System of a Garbage Incineration Power Plant 被引量:3
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作者 Wu Yuefeng 《Meteorological and Environmental Research》 CAS 2018年第2期58-61,66,共5页
A garbage incineration power plant is proposed to be built somewhere. Due to local environmental capacity and local policy,the demand on the flue gas emission indicators of the project is high,but the conventional pur... A garbage incineration power plant is proposed to be built somewhere. Due to local environmental capacity and local policy,the demand on the flue gas emission indicators of the project is high,but the conventional purification process of flue gas produced during waste incineration( SNCR denitrification +dry/semi-dry deacidification + adsorption of dioxins and heavy metals by activated carbon + bag dusting) has been unable to meet this requirement,and the newly added wet deacidification and SCR denitrification processes can meet this requirement. The flue gas purification process was optimized,and two feasible schemes were compared to choose the better one. 展开更多
关键词 Garage incineration power plant Flue gas purification optimization of schemes
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Optimal Schemes of Teleportation One-Particle State by a Three-Particle General W State 被引量:1
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作者 查新未 宋海洋 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第5期852-854,共3页
Recently, Xiu et al. [Commun. Theor. Phys. 49 (2008) 905] proposed two schemes of teleporting an N particle arbitrary and unknown state when N groups of three particle general W states are utilized a.s quantum chann... Recently, Xiu et al. [Commun. Theor. Phys. 49 (2008) 905] proposed two schemes of teleporting an N particle arbitrary and unknown state when N groups of three particle general W states are utilized a.s quantum channels. They gave the maximal probability of successful teleportation. Here we find that their operation is not the optimal and the successful probability of the teleportation is not maximum. Moreover, we give the optimal schemes operation and obtain maximal successful probability for teleportation. 展开更多
关键词 optimal operation scheme probability teleportation general W states
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Research of University Educational Administration System Bottlenecks and Overall Optimization Scheme 被引量:1
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作者 Lv Shenmin 《International Journal of Technology Management》 2014年第5期74-76,共3页
This paper analyzes of the bottleneck to influence the running efficiency of educational administration system in universities and colleges,and from the system deployment architecture, server configuration, database S... This paper analyzes of the bottleneck to influence the running efficiency of educational administration system in universities and colleges,and from the system deployment architecture, server configuration, database SQL statement optimization and other aspects, it puts forwards the optimization scheme. 展开更多
关键词 UNIVERSITY Educational administration system The bottleneck of the system The optimization scheme
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A New D-optimal Design Scheme for the Identification of Cubic Polynomials
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作者 李东林 田自耘 +1 位作者 张宏伟 郭素云 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1995年第4期24-27,共4页
In this paper, the limitations of the single cube D-optimal design scheme is studied, and a double cube D-optimal design scheme is suggested in order to overcome the limitations. For a sort of incomplete cubic polynom... In this paper, the limitations of the single cube D-optimal design scheme is studied, and a double cube D-optimal design scheme is suggested in order to overcome the limitations. For a sort of incomplete cubic polynomials, the test design of the identification is developed with this new scheme, and the comparation with the single cube scheme is also given. This scheme is shown to be perfectly suitable for the optimal identification of the complete cubic polynomials. 展开更多
关键词 ss: Identification regression optimAL DESIGN D-optimal DESIGN scheme
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Optimal Selection Model of Equipment Design Scheme Based on Set Pair Analysis
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作者 赵劲松 康建设 +1 位作者 张春润 贺宇 《Journal of Donghua University(English Edition)》 EI CAS 2015年第6期982-985,共4页
Selecting the optimal one from similar schemes is a paramount work in equipment design.In consideration of similarity of schemes and repetition of characteristic indices,the theory of set pair analysis(SPA)is proposed... Selecting the optimal one from similar schemes is a paramount work in equipment design.In consideration of similarity of schemes and repetition of characteristic indices,the theory of set pair analysis(SPA)is proposed,and then an optimal selection model is established.In order to improve the accuracy and flexibility,the model is modified by the contribution degree.At last,this model has been validated by an example,and the result demonstrates the method is feasible and valuable for practical usage. 展开更多
关键词 set pair analysis(SPA) equipment design scheme optimal selection model nearness degree
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Optimization Scheme Based on Differential Equation Model for Animal Swarming
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作者 Takeshi Uchitane Atsushi Yagi 《Open Journal of Optimization》 2013年第2期45-51,共7页
This paper is devoted to introducing an optimization algorithm which is devised on a basis of ordinary differential equation model describing the process of animal swarming. By several numerical simulations, the natur... This paper is devoted to introducing an optimization algorithm which is devised on a basis of ordinary differential equation model describing the process of animal swarming. By several numerical simulations, the nature of the optimization algorithm is clarified. Especially, if parameters included in the algorithm are suitably set, our scheme can show very good performance even in higher dimensional problems. 展开更多
关键词 optimIZATION scheme DIFFERENTIAL EQUATION Model ANIMAL SWARMING
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Optimazing operation and maintenance Telang II tidal reclamation scheme in relation to agricultural development
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作者 Megawaty   Robiyanto Hendro Susanto +1 位作者 F. X. Suryadi Ngudiantoro   《Agricultural Sciences》 2012年第2期287-298,共12页
The objective of this research is to study the hydraulic performance of the water management system of the Telang 2 tidal lowland reclamation scheme with respect to the operation and maintenance of the system. The hyd... The objective of this research is to study the hydraulic performance of the water management system of the Telang 2 tidal lowland reclamation scheme with respect to the operation and maintenance of the system. The hydraulic performance of the system should inline with the food crop water requirement and its cropping pattern. Based on the result of this research, a basic model will be set up in order to support a sustainable agricultural development in the area. The methodology of this research consists of 1) Analysing the hydraulic performance of the water management system for the existing condition as well as under the proposed scenarios;2) socio-economical approach to the related farmers in relation to the operation and maintenance of the water management system;3) Mathematical modelling of crop water requirement and an optimal water management system and its water management zoning system;4) Cost benefit analysis related to operation and maintenance of the water management system, role sharing and cost sharing. In this study, computer softwares CROPWAT, DUFLOW dan ArcGIS have been used as supporting tools in the analysis and evaluation. CROPWAT model was used for calculating the crop water requirement based on the climatological condition and proposed cropping pattern (rice-maize and rice-rice) and its calendar. Based on the result of the CROPWAT model, DUFLOW model was used in order to evaluate the capacity and hydraulic performance of the open canal system. Finally based on the field water layer condition, water management zoning can be derived by using ArcGIS in relation to the crop water requirement and required water levels in the water management system. Based on this research, it can be concluded that the cropping pattern rice-rice or rice-maize are preferable and the co sharing is 50% by the Government and 50% by the farmers is the best option and this is also inline with the hydro-topographical condition of the related area. 展开更多
关键词 optimalization Water Management TIDAL LOWLAND RECLAMATION scheme Mathematical Modelling
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Scheme optimization of AT shifting element based on genetic algorithm
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作者 岳会军 刘艳芳 +2 位作者 马明月 徐向阳 王书翰 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第2期539-545,共7页
In order to realize the computer aided design of AT shifting element schemes, a mathematical model of shifting element schemes which can be easily identified by computers was built. Taking the transmission ratio seque... In order to realize the computer aided design of AT shifting element schemes, a mathematical model of shifting element schemes which can be easily identified by computers was built. Taking the transmission ratio sequence as an optimization objective and simple shifting logic between adjacent gears through operating only one shifting element as a constraint condition, a fitness function of shifting element schemes was proposed. ZF-8AT shifting element schemes were optimized based on GA work-box of MATLAB, and the feasibility of the optimization algorithm was verified. 展开更多
关键词 hydrodynamic automatic transmission shifting element scheme optimization
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Upgrade and Optimization Scheme:GSM Intelligent Network to Destination Network
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作者 Guo Zhong Xu Kai(Jiangsu Branch of China United Telecommunications Corporation,Nanjing 210000,China) 《ZTE Communications》 2007年第4期50-54,共5页
The networking of intelligent networks involves overlay network and destination network.Destination network triggers intelligent services by the CAMEL Subscription Information(CSI),and it has broader applications than... The networking of intelligent networks involves overlay network and destination network.Destination network triggers intelligent services by the CAMEL Subscription Information(CSI),and it has broader applications than overlay network.Upgrade from existing network to destination network requires a multitude of preparations and tests.Cities and provinces upgrade their networks from the aspects of Service Control Point(SCP),Home Location Register(HLR),Mobile Switching Center(MSC),Gateway Mobile Switching Center(GMSC)and subsciption information through different processes.In order to fully realize the destination network after upgrading the accounting systems,the bill collection have to be rebuilt while the value-added services have to be upgraded.However,many difficulties,such as the Originating-CAMEL Subscription Information(O-CSI),the Terminating-CAMEL Subscription Information(T-CSI),and the special access number optimization,which all needs a particular solution,exist in upgrading. 展开更多
关键词 HLR MSC GSM Upgrade and optimization scheme
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Higher Order Iteration Schemes for Unconstrained Optimization
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作者 Yangyang Shi Pingqi Pan 《American Journal of Operations Research》 2011年第3期73-83,共11页
Using a predictor-corrector tactic, this paper derives new iteration schemes for unconstrained optimization. It yields a point (predictor) by some line search from the current point;then with the two points it constru... Using a predictor-corrector tactic, this paper derives new iteration schemes for unconstrained optimization. It yields a point (predictor) by some line search from the current point;then with the two points it constructs a quadratic interpolation curve to approximate some ODE trajectory;it finally determines a new point (corrector) by searching along the quadratic curve. In particular, this paper gives a global convergence analysis for schemes associated with the quasi-Newton updates. In our computational experiments, the new schemes using DFP and BFGS updates outperformed their conventional counterparts on a set of standard test problems. 展开更多
关键词 UNCONSTRAINED optimization ITERATION scheme ODE Method QUASI-NEWTON Update Convergence Analysis
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The scheme optimization on construction diversion with discharge control feature of upstream operational reservoir
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作者 Liu Quan Hu Zhigen +2 位作者 Fan Wuyi Ni Jinchu Li Qinjun 《Engineering Sciences》 EI 2012年第4期61-67,82,共8页
There is a discharge control feature of construction diversion system with the upstream operational reservoir. The risk evaluation model of construction diversion is established by taking into consideration the risk f... There is a discharge control feature of construction diversion system with the upstream operational reservoir. The risk evaluation model of construction diversion is established by taking into consideration the risk factors of construction diversion system with discharge control feature as well as their composition. And the risk factors include the upstream operational reservoir discharge control, the interval flood and branch flood and the diversion system itself. And then based on analyzing of the conversion relation between risk index and investment index of diversion scheme, the risk control and conversion principals of diversion system are put forward, and the feasible diversion scheme model is built. At last, the risk and economic evaluation and scheme economic feasibility analysis method of diversion scheme are shown by an example of construction diversion scheme optimization with the discharge control condition of upstream hydropower station. The study is valuable for establishment and optimization of construction diversion scheme with upstream reservoir discharge control. 展开更多
关键词 construction diversion cascade hydropower development risk analysis scheme optimization
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OPTIMAL SCHEME FOR SEQUENTIAL COMPUTATIONS OF F_m(z) INTEGRALS IN AB INITIO CALCULATIONS----COMBINATORY USE OF UPWARD AND DOWNWARD RECURSIONS
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《Chemical Research in Chinese Universities》 SCIE CAS 1986年第1期76-84,共9页
The quantitative rules of the transfer and variation of errors,when the Gaussian integral functions F.(z) are evaluated sequentially by recurring,have been expounded.The traditional viewpoint to negate the applicabili... The quantitative rules of the transfer and variation of errors,when the Gaussian integral functions F.(z) are evaluated sequentially by recurring,have been expounded.The traditional viewpoint to negate the applicability and reliability of upward recursive formula in principle is amended.An optimal scheme of upward-and downward-joint recursions has been developed for the sequential F(z) computations.No additional accuracy is needed with the fundamental term of recursion because the absolute error of Fn(z) always decreases with the recursive approach.The scheme can be employed in modifying any of existent subprograms for Fn<z> computations.In the case of p-d-f-and g-type Gaussians,combining this method with Schaad's formulas can reduce,at least,the additive operations by a factor 40%;the multiplicative and exponential operations by a factor 60%. 展开更多
关键词 COMBINATORY USE OF UPWARD AND DOWNWARD RECURSIONS INTEGRALS IN AB INITIO CALCULATIONS optimAL scheme FOR SEQUENTIAL COMPUTATIONS OF F_m down AB
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Study on joint optimization operation scheme forPangduo reservoir and Zhikong reservoir
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作者 WANG Qiang 《东北水利水电》 2018年第12期71-72,共2页
The cascade hydropower system composed of Pangduo reservoir and Zhikong reservoir are formed on the middlereach of the main Lasahe river. For giving full play of joint compensation effect of the two reservoirs, the pa... The cascade hydropower system composed of Pangduo reservoir and Zhikong reservoir are formed on the middlereach of the main Lasahe river. For giving full play of joint compensation effect of the two reservoirs, the paper studied the joint operationscheme for Pangduo reservoir and Zhikong reservoir. Based on the respective operation scheme, a reservoir group joint operationmodel is built, the model is solved by the simulation- optimization method, and then the practical and operational scheme isachieved. The scheme could give full play of the joint regulation and storage effect of the reservoir group and improve effectivelythe utilization factor of hydropower resources. 展开更多
关键词 RESERVOIR operation CASCADE RESERVOIRS JOINT operation scheme simulation optimIZATION
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