%0 Journal Article
%T Effective Location Acquisition Control Algorithms for the Location-Based Alert Services in Mobile Environments
%A So-Young Kang
%A Kwang-Jo Lee
%A Sung-Bong Yang
%J International Journal of Computer Networks & Communications
%D 2010
%I Academy & Industry Research Collaboration Center (AIRCC)
%X The location-based alert services can be regarded as the one of the most practical locationbasedservices. For the services, an alert service system for the services alerts mobile device users whenthey enter into or leave from predefined specific regions, and provides certain services previously askedby the users for special purposes such as security. For providing proper services the alert service systemshould acquire the location information of the users periodically. However, the system that handles thelocations of the users may face serious problems as the number of users increases fast. Hence it is acritical issue to properly adjust the time interval of location data acquisitions while maintaining theaccuracy of the services. In this paper we propose effective location acquisition algorithms; the speedbasedacquisition algorithm, the angle¨Cbased acquisition algorithm, and the hybrid algorithm combiningthe speed with the angle-based algorithms. We also present three grid-based acquisition algorithms inwhich a longer time interval is used when a user is not near the alert areas. The proposed algorithmscould reduce the amount of location information to be acquired based on the movement of the users. Theaverage numbers of location acquisitions of the speed-based, the angle¨Cbased, and the hybrid algorithmswere reduced by 19.2%, 35.8%, and 35.6% over the distance-based algorithm, respectively, while theymaintained the almost same level of accuracy. Among the grid-based algorithms, the grid-angleacquisition algorithm further improved the average number of acquisitions by 5.2% over the angle-basedalgorithm, which is 41.0% improvement over the distance-based algorithm. The experimental results alsoshow that all the grid-based algorithms showed almost equal accuracy.
%K Location-based alert services
%K LBS
%K Location information acquisition
%K Distance-based acquisition algorithm
%U http://airccse.org/journal/cnc/0110s03.pdf