A SMART-GATE BASED COMPOSITION METHOD TO PROVIDE SERVICES BY SOLVING CONFLICT USING DYNAMIC USER PRIORITY AND COMPROMISE POLICY1

摘要

Context-aware service is a hot topic in the research filed of ubiquitous computing. Composition of smart objects/context provides a flexible way to compose context-aware services, which means related smart objects around a user automatically being integrated together to provide the appropriate services. However, (1) there is no effective mechanism to coordinate the work of multiple smart objects and solve conflict problem in composition of smart objects; (2) priority is an effective method to solve conflict problem, however, the current priority based policies are static and thus not flexible; (3) when a conflict occurs for a numeric action of a smart object, e.g., changing of volume of a TV, it is not reasonable to just follow allothing policy, i.e., satisfy one user's requirement and ignore another one's, however, to find a compromised value to satisfy both users as much as possible. To solve the above problems, in this paper, a smart-gate based composition method is proposed. The smart gate has uniform interface to communicate with multiple smart objects and modules to coordinate the work of multiple smart objects and resolve conflict of services. Moreover, two novel policies are proposed in the smart gate for solving the conflict problem. One is a dynamic user priority based policy. The other is a compromise policy to minimize the required tolerance of users. Finally, we evaluate the proposed method through an experiment. The experiment result shows that the composition method works well and effective for resolving conflict problem.