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In an open and dynamic environment, due to the changes in the application’s domain or the user’s requirements, the domain knowledge changes over time and ontology evolves continually. Pi-calculus is a kind of mobile process algebra which can be used for modeling concurrent and dynamic systems. Based on the pi-calculus, this paper proposes a kind of ontology process model used for solving the change implementation and propagation problems in ontology evolution process. This solution is discussed at three levels: the change implementation of single ontology evolution, the push-based synchronization realization for the change propagation in the evolution of multiple dependent ontologies within a single node, and the pull-based synchronization realization for the change propagation of the distributed ontologies evolution.

Based on the pi-calculus, this paper proposes a kind of ontology process model used for solving the change implementation and propagation problems of ontology evolution process. This solution is discussed at three levels: the change implementation of single ontology evolution, the push-based synchronization realization for the change propagation in the evolution of multiple dependent ontologies within a single node, and the pull-based synchronization realization for the change propagation of the distributed ontologies evolution.

The integration of distributed and heterogeneous ontologies is one of the basic problems in the development of techniques for the Semantic Web. Ontological interoperability is not obtained simply by making a global level common ontology that captures the mapping between different local ontologies. It is very common in the Semantic Web that concepts represented in different ontologies are mutually inconsistent. This paper provides a unique pragmatic view on developing a tool for ontology integration.

Researchers need to share information about their publications. They also desire to share opinions and comments about each other’s publications. The paper describes a system which demonstrates how semantic blogging can be used for the purpose. The SWRC ontology has been incorporated in the blogging system for entering the metadata of publications. The semantic blogging system provides means to annotate publications. The system is a decentralized publication aggregation system. It utilizes the RSS technology to aggregate posts. The publication metadata is embedded in the RSS to produce BuRST feed. The RSS aggregator has been extended to handle the BuRST feeds. The system uses the FOAF links of the authors and friends to explore the social network of the research community for aggregation of relevant information.

This paper presents a case-study of converting the content of an existing eLearning portal based on the Learning Object Metadata (LOM) format into a semantic portal. It is shown how the content can be provided for the end-user from dierent semantic perspectives (views) based on a set of ontologies whose concepts are extracted from the original metadata. A semantic recommender system based on the same ontologies and metadata enhances the system usability further. This recommender system links the learning objects of the portal with each other with short labels that explain to the end-user the reason for the links, which is especially important in the eLearning domain. Furthermore, the system links the material also with the content of another cultural semantic portal, providing interportal semantic links. The application, consisting of some 2200 video and audio clips as learning objects, is available on the web where it can be compared with the original portal.

In order to reuse and assess ontologies, it is critical for on- tology engineers to represent and manage ontology versioning and evolu- tions. In this paper, we propose a timing analysis model for ontology evo- lution management with more speci¯c time constraints in a distributed environment. In the model, a timed change operation sequence is called a timed evolution behavior that must satisfy all of the time constraints in a distributed environment. Using this timing analysis model, we can detect whether ontology evolutions are timing consistent in the distributed en- vironment. Given a timed change operation sequence, we also can detect whether it is a timed evolution behavior of the distributed environment. All of these detections can be reduced to detecting whether the group of inequalities has solutions. This enables us to better manage dynamic versioning and evolutions of distributed ontologies. We also developed a prototype system called TEAM that can perform our timing analysis task of distributed ontology evolutions.

Methodologies to find and evaluate solutions for ontology matching should be centered on the practical problems to be solved. In this paper we look at matching from the perspective of a practitioner in search of matching techniques or tools.We survey actual matching use cases, and derive general categories from these. We then discuss the value of existing techniques for these categories.

The reasons for the lack of uptake of the semantic web amongst ordinary users can be attributed to technology perception, comprehensibility and ease of use. To address these three problems, we believe that the interfaces to ontology management tools will need to be engineered in such a way as they disappear into the background from the ordinary person’s perspective. The majority of the state of the art approaches to ontology mapping relies on the user being ontologically aware. In contrast, this paper reports upon an approach to use ‘tagging’ as a means of ontology mapping to support ordinary people.

Numerous ontology alignment algorithms have appeared in the literature in recent years, but only a few make use of the semantics enclosed within the ontologies in order to improve the accuracy. In this paper, we present the Automated Semantic Mapping of Ontologies with Validation (ASMOV) algorithm for ontology alignment. We first provide a brief overview of the algorithm followed by an analysis of its results on the 2007 Ontology Alignment Evaluation Initiative tests. We conclude the paper by identifying the specific strengths and weaknesses of ASMOV, while pointing out the necessary improvements that need to be made.

Within Semantic Web environments, ontologies have been adopted as their conceptual backbone. An important task for Web infor- mation integration and sharing is to resolve semantic con°icts because of semantic heterogeneity and information incompleteness. But it is rather di±cult for ontology engineers to integrate Web information with seman- tic heterogeneity and con°icts. In this paper, a priority based approach is proposed for handling semantic con°icts from ontology information. We can automatically check where semantic con°icts probably exist, and further ¯x so called con°ict points of ontology information. Semantic con°icts can be semi-automatically eliminated by assigning di®erent pri- orities to related rules of con°ict points. Then semantic based query can be performed for information sharing. A case system called CIMS based on ontology representation is implemented for illustrating our method.