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Study on Garden Plant Species and Their Disposition Optimization in Arid Valley of West China
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作者 谢学强 《Journal of Landscape Research》 2010年第12期68-72,共5页
Based on survey of plant species and disposition in major gardens at arid valley and optimization of plant disposition in Sichuan University for Nationalities,the study pointed out the overall target for disposition o... Based on survey of plant species and disposition in major gardens at arid valley and optimization of plant disposition in Sichuan University for Nationalities,the study pointed out the overall target for disposition optimization of garden plants in arid valley,concluded the principles and approaches to optimize garden plant disposition at arid valley and highlight garden features at arid valley,emphasized the vital significance to develop local wild plant resources and introduce exotic garden plants. 展开更多
关键词 ARID valley GARDEN PLANT species PLANT disposition optimization
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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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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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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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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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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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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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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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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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Research progress on subjective well-being and dispositional optimism of the elderly
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作者 Li Zhu Xiang-Shu Cui 《Psychosomatic Medicine Research》 2022年第3期24-29,共6页
The subjective well-being of the elderly is an integral part of healthy aging.This review introduces the concept of subjective well-being of the elderly and the evaluation tools used,reviews the influencing factors of... The subjective well-being of the elderly is an integral part of healthy aging.This review introduces the concept of subjective well-being of the elderly and the evaluation tools used,reviews the influencing factors of subjective well-being of the elderly,and summarizes the intervention measures of subjective well-being of the elderly.From the perspective of positive psychology,based on the introduction of the concept and evaluation tools of temperament optimism,this paper reviews the research status of temperament optimism and subjective well-being and the research progress of their correlation,so as to provide a theoretical basis for the intervention to improve the subjective well-being of the elderly. 展开更多
关键词 The elderly Subjective well-being dispositional optimism OVERVIEW
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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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A Novel Approach for Optimal Schemes in Progressive Censoring Plans
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作者 Z. A. Abo-Eleneen 《通讯和计算机(中英文版)》 2012年第4期426-433,共8页
关键词 优化方案 寿命试验 最佳方案 删失数据 最优准则 寿命分布 联合熵 最大熵
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Novel Discrete Particle Swarm Optimization Based on Huge Value Penalty for Solving Engineering Problem 被引量:7
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作者 YU Ying YU Xiaochun LI Yongsheng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2009年第3期410-418,共9页
For the purpose of solving the engineering constrained discrete optimization problem, a novel discrete particle swarm optimization(DPSO) is proposed. The proposed novel DPSO is based on the idea of normal particle s... For the purpose of solving the engineering constrained discrete optimization problem, a novel discrete particle swarm optimization(DPSO) is proposed. The proposed novel DPSO is based on the idea of normal particle swarm optimization(PSO), but deals with the variables as discrete type, the discrete optimum solution is found through updating the location of discrete variable. To avoid long calculation time and improve the efficiency of algorithm, scheme of constraint level and huge value penalty are proposed to deal with the constraints, the stratagem of reproducing the new particles and best keeping model of particle are employed to increase the diversity of particles. The validity of the proposed DPSO is examined by benchmark numerical examples, the results show that the novel DPSO has great advantages over current algorithm. The optimum designs of the 100-1 500 mm bellows under 0.25 MPa are fulfilled by DPSO. Comparing the optimization results with the bellows in-service, optimization results by discrete penalty particle swarm optimization(DPPSO) and theory solution, the comparison result shows that the global discrete optima of bellows are obtained by proposed DPSO, and confirms that the proposed novel DPSO and schemes can be used to solve the engineering constrained discrete problem successfully. 展开更多
关键词 discrete particle swarm optimization location updating scheme of constraints level huge value penalty optimization design BELLOWS
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A New Integrated Design Method Based on Fuzzy Matter-Element Optimization 被引量:5
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作者 ZHAO Yan-wei 1, ZHANG Guo-xian 2 (1. College of Mechanical Engineering, Zhejiang University o f Technology, Hangzhou 310014, China 2. College of Mechanical & Electronic al Engineering, Shanghai University, Shanghai 200072, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期136-,共1页
This paper puts forward a new integrated design met ho d based on fuzzy matter-element optimization.On the based of analyzing the mod el of multi-objective fuzzy matter-element , the paper defines the m atter-element ... This paper puts forward a new integrated design met ho d based on fuzzy matter-element optimization.On the based of analyzing the mod el of multi-objective fuzzy matter-element , the paper defines the m atter-element weightily and changes solving multi-objective fuzzy optimization into solving dependent function K(x) of the single-objective optimization according to the optimization criterion. The paper particularly describes the realization approach of GA process of multi -objective fuzzy matter-element optimization: encode, produce initial populati on, confirm fitness function, select operator, etc. In the process, the adaptive macro genetic algorithms (AMGA) is applied to enhancing the evolution speed. Th e paper improves the two genetic operators: crossover and mutation operator. The modified adaptive macro genetic algorithms (MAMGA) is put forward simultane ously. It is adopted to solve the optimization problem. Three optimization methods, namely fuzzy matter-element optimization method, li nearity weighted method and fuzzy optimization method, are compared by using the table and figure, it shows that not only MAMGA is a little better than the AMGA , but also it reaches the extent to which the effective iteration generation is 62.2% of simple genetic algorithms (SGA). By the calculation of optimum exam ple, the improved method of genetic in the paper is much better than the method in reference of paper. 展开更多
关键词 multi-objective optimization fuzzy matter-elem ent genetic algorithms scheme design
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Multi-objectives fuzzy optimization model for ship form demonstration based on information entropy 被引量:4
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作者 ZHANG Wei-ying LIN Yan +1 位作者 JI Zhuo-shang DENG Lin-yi 《Journal of Marine Science and Application》 2006年第1期12-16,共5页
Selecting optimization ship form scheme is an important content in the process of concept design of ship. Multi-objective fuzzy decision-making model for ship form demonstration is set up according to the fuzzy patter... Selecting optimization ship form scheme is an important content in the process of concept design of ship. Multi-objective fuzzy decision-making model for ship form demonstration is set up according to the fuzzy pattern-recognition theory. Weight coefficients of each target of ship form scheme are determined by information entropy and individual subjective partiality. This model is used to select the optimal ship form scheme, the example shows that the model is exact and the resuh is credible. It can provide a reference for choosing the optimization scheme of ship form. 展开更多
关键词 ship form scheme information entropy MULTI-OBJECTIVE fuzzy optimization
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Perforation optimization of layer-penetration fracturing for commingling gas production in coal measure strata 被引量:5
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作者 Bing Hou Zhuang Cui +3 位作者 Ji-Hui Ding Feng-Shou Zhang Li Zhuang Derek Elsworth 《Petroleum Science》 SCIE CAS CSCD 2022年第4期1718-1734,共17页
Optimization of fracturing perforation is of great importance to the commingling gas production in coal measure strata.In this paper,a 3 D lattice algorithm hydraulic fracturing simulator was employed to study the eff... Optimization of fracturing perforation is of great importance to the commingling gas production in coal measure strata.In this paper,a 3 D lattice algorithm hydraulic fracturing simulator was employed to study the effects of perforation position and length on hydraulic fracture propagation in coal measures of the Lin-Xing block,China.Based on field data,three lithologic combinations are simulated:1)a thick section of coal seam sandwiched by sandstones;2)a thin coal seam layer overlay by gas-bearing tight sandstone;3)two coal seams separated by a thin layer of sandstone.Our simulation shows that perforation position and length in multi-layer reservoirs play a major role in hydraulic fracture propagation.Achieving maximum stimulated volume requires consideration of lithologic sequence,coal seam thickness,stress states,and rock properties.To improve the combined gas production in coal measure strata,it is possible to simultaneously stimulate multiple coal seams or adjacent gas-bearing sandstones.In these cases,perforation location and length also significantly impact fracture propagation,and therefore should be carefully designed.Our simulation results using 3 D lattice algorithm are qualitatively consistent with laboratory physical simulation.3 D lattice models can be used to effectively simulate the fracture propagation through layers in coal measure strata.The numerical results provide guidance for perforation optimization in the hydraulic fracturing of coal measure strata. 展开更多
关键词 Coal measure strata Combined production 3D lattice algorithm Perforation scheme optimization Fracture propagation
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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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