Dissertation > Excellent graduate degree dissertation topics show

The Research of QoS-Aware Web Services Selection and Fault-Tolerance of Runtime Service Composition

Author: CaiMeiLing
Tutor: GaoChunMing
School: Hunan Normal University
Course: Computer Software and Theory
Keywords: Service Composition Quality of Service Genetic Algorithms Tree-coding failure-tolerance replaning
CLC: TP393.09
Type: Master's thesis
Year: 2007
Downloads: 229
Quote: 4
Read: Download Dissertation

Abstract


As the newest application model for decentralized computing,Web service is an effective mechanism for the data and service integration on the Internet. Services composition is a process that assembles multiple component services according to their functionality, semantica and logic relationships to a composite service for providing new functionality.As Web services increase explosively,the number of services with similar functionality or implementing the same function is larger and larger,so selecting the component service considering non-functionality (i.e.QoS) is a critical technology of Web service composition.In addition,the component services of composition service may fail for various factors when running in the dynamic environment.For the sake of making users aware of the failure,it is important to re-select available Web composition plans to complete the business process required,and at the same time to satisfy the users’ preference and constraints set by the user or by the structure of the composite services. This is fault-tolerance of composition service at run time.Our work mainly focuses on providing business with certain quality effectively in the complex environment of Internet,according to users’ requirements.First of all,a Web service architecture (Web Jet) is proposed to support QoS-aware Web service selection and failure-tolerant processing of composition services at run time. QoS model Web Jet adopted is introduced,so are the QoS computing methods of single service and composite service.Then we contrive a QoS-driven global optimization algorithms named TGA for services selection based on Genetic Algorithms (GAs).We designed a novel data model- Process Tree(PTree) model to describe combination relationships among the tasks in composition services.PTree model provides good data structure for QoS computation of specific Composition Plan,and it is also the critical factor for replanning Web Services Composition at run time.Based on PTree which can express abstract process of composite service,we design Tree-coding scheme as the chromosome code of TGA. The experiment results show that Tree-coding is effective in global optimization of services composition.We carried on a series of experiments comparing our TGA with the exact solutions for services composition(0-1 heuristics for QoS-aware Web Service Composition).The experiment results confirm that our Tree-coding Genetic Algorithms is effective in QoS-aware Web Service Composition.Due to the dynamic attributes of services composition execution environment,the component services may become unavailable or the QoS of the component service may change significantly.We researched on the run-time fault-tolerance mechanism of services composition.Three policies are proposed to adapt to dynamic environment.The policies are retrying to invoke the failure componet service, replacing the failure service with a new component service and replanning a local-process required to execute afterward. The experiments confirm the validity of replanning.For retrying and replanning mechanism,experiments are carried on to check their execution effects.

Related Dissertations

  1. Development of the on-line Training and Examination System of Army,TP311.52
  2. Designs and Applications of Fuzzy Synthetic Evaluation Models Based on Parallel Algorithms,TP18
  3. An Approach for Business Process Oriented Service Dynamic Composition,TP393.09
  4. Based on Genetic Algorithm Pishihang irrigation canal water allocation marshalling model of,S274
  5. Genetic Algorithm in logistics and warehousing Optimization Research,F259.2
  6. Mining resources based on genetic algorithm optimization model of,O224
  7. The Research and Application of Modified Algorithms About Fuzzy Predictive Functional Control,TP273
  8. Research on Petri Net-based Service-Oriented Modeling of Information Management Software,TP311.52
  9. The Research of Service Quality Management of Mobile Communication Industry in the Perspective of Customer Satisfaction,F626;F224
  10. Optimal Control of Emulsion System in Cold Rolling,TP273
  11. Research on the Marshalling-scheduling Model and Algorithms of Freight Trains Based on Game Theory,O225
  12. Multi-directional Mutation Genetic Algorithm and Research on Neural Network Optimization,TP18
  13. The Application of Using Genetic Algorithms on Universities Course-arranging System,TP18
  14. Research on Mobile Robot Path Planning and Simulation Realization,TP242
  15. Research on Routing Algorithmin Sensor Networks Based on Cluster with Mobile Sink,TP212.9
  16. Research and Implement of the Theme Crawler for Automotive Industry,TP391.3
  17. The Studies on Some Improvements of the GA and Their Applications in SVM,TP18
  18. Optimal Riser Design of Steel Casting Based on CAE Analysis,TG260
  19. In-furnace Temperature Information Included Combustion Optimization of a Utility Boiler,TK227.1
  20. Design of High-efficiency Thermophotovoltaic System,TM914.4
  21. Web Service Composition Based on QoS Awareness,TP393.09

CLC: > Industrial Technology > Automation technology,computer technology > Computing technology,computer technology > Computer applications > Computer network > General issues > The application of computer network
© 2012 www.DissertationTopic.Net  Mobile