A dynamic description logic based system for video event detection

Video event detection is an important research area nowadays.Modeling the video event is a key problem in video event detection.In this paper,we combine dynamic description logic with linear time temporal logic to build a logic system for video event detection.The proposed logic system is named as LTD_(ALCO)which can represent and inference the static,dynamic and temporal knowledge in one uniform logic system.Based on the LTD_(ALCO),a framework for video event detection is proposed.The video event detection framework can automatically obtain the logic description of video content with the help of ontology-based computer vision techniques and detect the specified video event based on satisfiability checking on LTD_(ALCO)formulas.

Dynamic hierarchy description and constraint rules of flexibility workflow

A dynamic hierarchical description method for workflow is presented. The method provides a dynamic hierarchical way to define a workflow with non-determinate or dynamic factors. With this method, the main process defined at build-time can be reified and extended by the principle of the sub-organizations at either the build-time or the run-time. To ensure the consistency and integrity of the description, a series of constraint rules are also discussed to realize seamless integration between a decomposed process and its original one. This approach supports the description of unpredictable uncertainties, the dynamic hierarchy of business process, and the dynamic modification of enterprise organizations, and all of these improve the flexibility and extendability of workflow management systems dramatically.

A Dynamic Fuzzy Description Logic

Fuzzy description logics are considered as the logical infrastructure of fuzzy knowledge representation on the semantic Web. To deal with fuzzy and dynamic knowledge on the semantic Web and its applications, a new fuzzy extension of Attribute Language with Complement based on dynamic fuzzy logic called the dynamic fuzzy description logic （DFALC） is presented. The syntax and semantics of DFALC are formally defined, and the forms of axioms and assertions are specified. The DFALC provides more reasonable logic foundation for the semantic Web, and overcomes the insufficiency of using fuzzy description logic FALC to act as logical foundation for the semantic Web. The extended DFALC is more expressive than the existing fuzzy description logics and present more fuzzy information on the semantic Web.

A logical foundation for the semantic Web

The current research progresses and problems of the semantic Web are analyzed in this paper, and the insufficiency of using description logic to act as logical foundation for the semantic Web is analyzed too. According to the characteristics and requirement of the semantic Web, a kind of new dynamic description logic (DDL) framework is presented. The representation and reasoning of static knowledge and dynamic knowledge are integrated in this framework. Especially, a kind of action description method is proposed, and according to description logic theory, the action semantics is described, so DDL is a kind of formal logical framework which can process static knowledge and dynamic knowledge. The DDL has clear and formally defined semantics. It provides decidable reasoning services, and it can support effective representation and reasoning of the static knowledge, dynamic process and running mechanism (realization and subsumption relation of action). Therefore, the DDL provides reasonable logic foundation for the semantic Web, and overcomes the insufficiency of using description logic to act as logical foundation for the semantic Web.