| With the rapid development of computer and network technology, the information process of this society is accelerated and deepened; the organization and information systems are also becoming more and more related. With the speeding up tempo of economy, the problems such as how to carry out effective integration of information systems in organization and make it adaptive with the changes in external environment, how to meet fast-changing customer requirements timely so as to keep information superiority in fierce competition environment, have become severe challenges in the information construction of many organizations. In recent years, the use of services to encapsulate heterogeneous application and data resources, while using service composition to build complex application inter-organization, has become the prevailing trend in distributed computing technology, and the composite services become an important form in the construction of cross-organization applications. In this background, the research on evolution method of composite services has far-reaching significance for improving the ability of applications to adapt with external changing environment.Taking composite services in semantic web environments as research object, the challenges in composite service evolution are analyzed systematically in this dissertation. The structural evolution method of semantic web services (SWS) is introduced in this dissertation, then, to realize automatic assistant process in the evolution cycle, several key technologies are studied, such as formalization of composite service evolution requirements, syntactic consistency maintenance of service description, and semantic consistency analysis of OWL-S service description. The main contributions of this dissertation are as follows:(1) Research on the structural evolution method of composite services in semantic web envrionment. Composite service evolution is an important component of change management in composite service life cycle, and it is usually a complicated job to evolve composite service when face to complex applications. In this dissertation, a semantic web service evolution method EM4CS is introduced, which take SWS described by OWL-S ontology as research object. EM4CS divide the composite service evolution process into 6 stages and 12 sub-processes. First, EM4CS will guide knowledge engineerer (KE) to obtain evolution requirements from problem domain, and then these requirements will be formalized as Maintenance Request Script (MRS) on the basis of Evolution Ontology (EO). On the driven of MRS, the syntactic and semantic consistency maintenance will be finished in an iterative refined way. After the evolution results are confirmed, these results will be published and broadcasted, so that, the related applications and running instances can synchronize former changes, and global application consistency should be realized.(2) Research on formal representation of composite service evolution requirements based on Evolution Ontology (EO). The formal representation of evolution requirements is the base of EM4CS, which make evolution intentions of KE understandable by machine. In this work, the core concepts of SWS are defined according to the OWL-S syntactic specification, and a complete basic change operation set which orient to these core concepts is introduced, while composite change operations in higher abstract layer are also defined. Then, an Evolution Ontology is introduced to define such change operations, relations between these changes and inference rules of these changes formally. On the basis of EO, the evolution requirements are formally represented by concept Maintenance Request (MR) on service description. MR is composed of positive change list (PCL) and negative change list (NCL), the former represent goals of service description modification, while the latter represent the constrain conditions in the process of composite service evolution. At last, in the support of EO, the potential conflictions in MR can be found through reasoning method, so that the efficiency in follow-up stages of composite service evolution can be improved.(3) Research on the method to check and maintain the syntactic consistency of OWL-S service description. In this work, the syntactic consistent constraints are defined formally according to OWL-S syntactic specification, and then a method to check syntactic consistency of OWL-S service description is given. So as to resolve syntactic inconsistency on the aid of machine, the inconsistency resolving strategies are analyzed in this paper, and a resolve strategy configuration vector is proposed to represent the private inconsistency resolving requirement of KE. At last, an algorithm named SCMA is proposed to obtain the available syntactic consistency maintenance plan. In SCMA, the processes of implementation of maintenance request script and maintenance of syntactic consistency of OWL-S service description are considered together, so that, the available maintenance plan will be constructed in an iterative way.(4) Research on the technology to analyze semantic consistency of OWL-S service description. In this dissertation, semantic consistency of composite service is divided into two types, i.e. data semantic consistency and procedural semantic consistency, the former analyzes the inclusions between concept types of source and destination parameters in dataflows; the latter mainly validates the composite logics in composite SWS. In this work, two methods are introduced to analyze data semantic consistency of OWL-S service description, i.e. method based on reasoning and method based on similarity computation of concepts. The former method can find out strict inclusion relation between concept types of source and destination parameters in dataflows, while the latter method can provide decision foundations through computing similarity probability between concepts. To analyze procedural semantic consistency, an extended petri net, which called Process Model Net (PM_net), is intorduced to model the process model of OWL-S service description, and the analysis of procedural semantic consistency is transformed into the soundness validation of underlying PM_net. Then, a PM_net soundness validation algorithm PSA_CG which based on analysis of coverability graph is presented to validate the procedural semantic consistency of OWL-S service description. At last, the reduction rules of PM_net and method to locate logic errors in OWL-S process model are depicted.(5) Based on the research of above-mentioned EM4CS methodology and key technologies, a composite service evolution support system ESS4CS that follow EM4CS is designed and realized. Then, an electronic trading service is taken as example to illustrate how to use EM4CS and ESS4CS system to evolve composite service, so the feasibility and effectiveness of EM4CS is further verified.To sum up, this dissertation presents a structural composite service evolution method in semantic web environment systematically, and researches on the key technologies involved. We believe that our contributions make a nice groundword for future research and engineering on improving the adaptability of composite service applications in dynamic environments.
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