Research On Context Aware Service Logic Modeling Based On Petri Net

With the development of computer and communication technology, the traditional computing mode has changed a lot. Since Mark Weiser proposed the concept of pervasive computing in 1991, pervasive computing has become a very important research branch of the new computing mode and application development in the future. Context-aware is a key point of pervasive computing and the context-aware application aims at providing the corresponding information and services by the intelligent judgment of users'behavior and purpose through the contextual information collected by the distributed sensors and also adjusts the form and the content of the services and information adaptively. At present, most context-aware applications can accomplish a specific service to a certain degree, while these services are triggered by the sensors. This method is useful and works well at the early stage of the context-aware application development when the contextual information is limited. However, when more and more contextual information can be acquired by the pervasive services, the behaviors of the context aware application become more complex, and the requirement of the context aware application service logic design reaches a new level. A well-designed service logic design method should make an entire support for the system developers and release the burden for them by reducing the possible mistake during the system development.This paper researches about the context aware service logic design and makes a survey of the recent research and trend in the field of pervasive computing. In addition, this paper makes a deep research focuses on proposing a systematic method of the context aware service logic design under the pervasive computing environment.This paper introduces the concept of context and context awareness firstly and then makes a survey of the traditional context aware service logic design methods at home and abroad. Based on the previous research, this paper proposes the context aware service logic model based on petri net. Then this paper introduces this method by three steps:transferring the scenario description from the initial service petri net logic model; constructing the context hierarchy and knowledge base; model consistency checking and model refinement. Then this paper proposes using the dynamic system simulation to simulate the service logic, in order to discover the potential conflict existed in the context aware service logic. Therefore, the service logic model can be ensured consistent not only in the static structure, but also during the dynamic running. In this part, this paper also introduces CPN Tools, which is used widely in the field of petri net simulation, and proposes the specific design method for context aware service simulation.The result of the research in this paper shows this context aware service logic design based on petri net partly solves some problems in the context aware application development. The context aware service logic is sound and incremental by using this method proposed in this paper. It will release the burden and reduce the mistakes for the developers during the context aware application design. This research has a significant value in the engineering use and is worth for the further research.