VPW: An Effective Personal Space Model for Providing Ubiquitous

User-centrism is one of the most important things in ubiquitous computing. Previously, lots of researches have addressed issues for ubiquitous computing, but most of them oversimplified a personal space as a set of devices in a fixed location or in a communication-ranged space. Thus, they have had a problem to describe sophisticated user-centric services. In this paper, we propose an effective personal space model called VPW (virtual personal world) for providing ubiquitous services. VPW includes various objects over several locations, tasks in progress, and proxies of other users. Thus, service provision based on VPW supports more delicate user-centric adaptation, use of multiple devices spread over locations, and harmony between multiple users and multiple services. Eventually, it increases user satisfaction in providing ubiquitous services. Experimental results show the VPW-based approach increase user satisfaction by around 20% compared to the location-based approach and by around 15% compared to the range-based approach