Research And Implementation Of Semantic Web Services Composition

With the development of information technology, more and more information isprovided to the users in the form of Web services. However, a single Web service isfunction limited, and often can not meet the complex and diverse user needs, so we needto compose multiple existing services to create a more powerful Web service. Under thatbackground, the introduction of semantic information drives the development ofautomantic Web services composition technology. Therefore, semantic based automaticWeb services composition technology has become a focus of study, and it has become anurgent problem to compose semantic Web services accurately, efficiently, andautomatically. The specific content of the paper is as follows.Firstly, this paper studies the semantic Web services composition method. This paperanalyzes the I/O based service relationships exist between the network services, and thenstudies four composition formations that may apppear in composition graph. On this basis,a service closure based semantic Web services composition approach is proposed to solvethe composition problem of the multi-input and multi-output reticular formation. Theapproach is divided into two stages. In the first stage, the approach finds out the Webservices associated with the composition to reduce the search space. In the second stage,the approach searches the results of the first stage backwardly, and gets the compositionresults.Secondly, this paper studies the services matching problem in the compositionprocess, and analyzes the semantic distance based similarity computation formula. On thisbasis, a fast I/O matchmaking approach is proposed according to the characteristics of theformula. The approach indexes the Web services before users submit a service request, andafter users submit the service request, it searches the index to get the matching services.The approach reduces the number of semantic similarity calculation, and improves thematchmaking efficiency.Finally, we develop a semantic Web services composition prototype system due to thelack of standard semantic Web services composition experimental platform and data, and elaborate the semantic Web services composition implementation process via describingone instance in detail. The prototype system achieves the composition approach proposedin this paper, and it verifies the feasibility of the composition approach.