Research On Semantic Interoperation For E-Government Information System

It's goal of every government in the world to build government information system via modern network technology. These systems can help governments to improve public services and public administration. The coordination government affairs and sharing of information resources are important contents in e-government building. While the problem of lacking consistent understanding of data between information systems has made the work of building become more difficultly and complexly. It's a good method to adopt semantic interoperation technology to solve problem mentioned above.Because semantic technology is in development, there are still many works to be done to realize semantic interoperation. There is semantic difference between local ontologies originated from autonomous information systems. Normal models of semantic interoperation are not suit for solving problem mentioned above, because they have not thoutht of characteristics of e-government. Whether can find information resource is precondition of semantic interoperation. Building Information resource catalog based on meta-data technology is a normal method now. When querying information resource, method based on key words matching is used, which have not good query quality. Even if information resource is found, its meaning is also lack, and mistake will be made because of semantic difference. The problem of how to transform data of data-source into semantic data should be considered. If relative data are transformed into static ontology, it will have big size which traditional reasoner can't deal with. If using segmentation technology at the same time, ontology segmented still has big size because of ontology instance is usually neglected by segmentation technology. Some algorithms translate semantic query into SQL statements to solve this problem, but they have limited supporting for semantic. There are semantic conflicts between data of autonomous information systems. Database schemas are mapped into local ontologies in normal methods, during which conflictions are eliminated. But only parts of conflictions are eliminated.On the basis of questions mentioned above, my main work and innovation points can be summarized as follow:(1)Propose a semantic interoperation model on e-government domain. Aiming at the complexity of data source, the concept of data view is proposed. Database tables and switch services are transformed into unified data form via data view. Meaning of data view relies on its original data source. Domain knowledge is presented as global ontology,local ontology and confliction ontology in my layered interoperation model. There are three kinds of mapping:data view to local ontology, local ontology to global ontology, local ontology to local ontology. With these mapping, semantic of data has been discovered and interoperation between ontologies has been realized.(2)Propose the concept and building method of semantic information resource catalog. The concept of semantic information resource catalog is proposed. That how to organize it is discussed also. Four kinds of rules are designed especially to dig out hidden semantics of data deeply.(3)Design the algorithm of querying on large scale of data source, which called DSQ. In the algorithm called DSQ, data schemas are transformed into ontology leaving data records having its original form. During the computing of DSQ, domain ontologies are transformed into GRAPH, semantic queries are also transformed into GRAPH, and semantic match is done between them. Result of match is transformed into SQL statements later. The algorithm called DSQ not only supports RDFs but also supports part of OWL DL vocabularies.(4)Propose a framework for solving semantic confliction. Having analyzed possible conflictions in semantic interoperation, the concept of semantic confliction is defined, and relative framework solving confliction is proposed which can eliminate many kinds of conflictions. Especially, a kind of confliction called property confliction is defined. Confliction ontology is designed to solve property confliction whose instances are dynamically managed.(5)Semantic interoperation framework for e-government information system is designed with prototype implementation. Theory in this dissertation is preliminarily verified by experiment.