本文選題：非線性規(guī)劃　切入點(diǎn)：Web服務(wù)組合　出處：《江西師范大學(xué)》2014年碩士論文

【摘要】：隨著Web服務(wù)的快速發(fā)展，，基于Qos的Web服務(wù)組合優(yōu)化問(wèn)題已經(jīng)成為Web服務(wù)的研究熱點(diǎn)。Web服務(wù)組合是NP-hard問(wèn)題。典型的與Web服務(wù)相關(guān)的Qos的屬性有響應(yīng)時(shí)間、吞吐率、到達(dá)率等。對(duì)基于Qos的Web服務(wù)組合優(yōu)化問(wèn)題的研究，可以更全面的滿足用戶對(duì)服務(wù)質(zhì)量的要求，這對(duì)于Web服務(wù)的發(fā)展具有十分重要的意義。 本文首先介紹了目前求解Web服務(wù)組合優(yōu)化問(wèn)題常用的幾個(gè)算法。主要有遺傳算法、粒子群算法等等。遺傳算法在求解Web服務(wù)優(yōu)化問(wèn)題中應(yīng)用廣泛，但其參數(shù)選取大多依靠經(jīng)驗(yàn)，不能保證解的有效性，并且在最優(yōu)解的搜索過(guò)程中容易陷入局部收斂。蟻群算法全局搜索能力強(qiáng)，但其模型并不能直接應(yīng)用于Web服務(wù)組合的實(shí)際優(yōu)化問(wèn)題。 本文將BPEL服務(wù)組合流程映射為排隊(duì)網(wǎng)絡(luò)，利用排隊(duì)網(wǎng)絡(luò)的理論對(duì)響應(yīng)時(shí)間、吞吐率以及到達(dá)率等Qos屬性進(jìn)行分析，并采用Mathematica對(duì)數(shù)據(jù)進(jìn)行計(jì)算。計(jì)算結(jié)果表明，該方法具有很強(qiáng)的實(shí)用性。 本文的研究?jī)?nèi)容是在給定的Web服務(wù)中利用非線性規(guī)劃算法優(yōu)選出一組Web服務(wù)，使得這組服務(wù)在滿足約束條件的前提下總費(fèi)用達(dá)到最小。本文基于排隊(duì)網(wǎng)絡(luò)理論，將BPEL順序結(jié)構(gòu)、BPEL條件結(jié)構(gòu)以及BPEL循環(huán)結(jié)構(gòu)映射為排隊(duì)網(wǎng)絡(luò)，利用排隊(duì)網(wǎng)絡(luò)的特點(diǎn)對(duì)三種結(jié)構(gòu)下Web服務(wù)的吞吐率進(jìn)行計(jì)算，進(jìn)而求解Web服務(wù)器的響應(yīng)時(shí)間關(guān)于節(jié)點(diǎn)i (1≤i≤N)的服務(wù)率的表達(dá)式。通過(guò)對(duì)響應(yīng)時(shí)間以及各個(gè)節(jié)點(diǎn)的服務(wù)率設(shè)置約束條件，建立非線性規(guī)劃模型，在Mathematica中對(duì)節(jié)點(diǎn)i (1≤i≤N)的服務(wù)率進(jìn)行求解。通過(guò)將求解的服務(wù)率與給定的Web服務(wù)的服務(wù)率相比較，選取與所求解的服務(wù)率相差最小的一組Web服務(wù)，就是本文所求的最優(yōu)Web服務(wù)組合。
[Abstract]:With the rapid development of Web services, the optimization of Web services composition based on Qos has become the research hotspot of Web services.Typical Qos attributes associated with Web services are response time, throughput, arrival rate, and so on.The research on the optimization of Web services composition based on Qos can more fully meet the requirements of users for the quality of service, which is of great significance for the development of Web services.This paper first introduces several algorithms commonly used to solve Web service composition optimization problem.There are genetic algorithm, particle swarm optimization algorithm and so on.Genetic algorithm (GA) is widely used in solving Web service optimization problem, but its parameter selection depends on experience, which can not guarantee the validity of the solution, and it is easy to fall into local convergence in the process of searching for the optimal solution.Ant colony algorithm has strong global search ability, but its model can not be directly applied to the practical optimization problem of Web service composition.In this paper, the BPEL service composition flow is mapped to a queueing network, and the response time, throughput and arrival rate are analyzed by using the queuing network theory, and the data are calculated by Mathematica.The calculation results show that the method is very practical.The purpose of this paper is to select a set of Web services by using nonlinear programming algorithm in a given Web service, so that the total cost of the set of services can be minimized under the premise of satisfying the constraint conditions.Based on the queuing network theory, the BPEL sequential structure and BPEL cyclic structure are mapped to queueing network, and the throughput of Web services under three kinds of structures is calculated by using the characteristics of queueing network.Then the expression of the response time of the Web server to the service rate of node I 1 鈮

本文編號(hào)：1711037