Automatic Inference Of Movements From Contact Histories

Location-Based service (LBS), also known as location-based services. It isthe application of wireless location technology. It provide location information(usually present as geographical coordinates) of mobile terminal users by meansof radio communication networks of the mobile operators (GSM, and CDMA) orexternal positioning (GSP). This technique along with GIS platform, can providevaluable services for users.LBS are used in a variety of contexts, such as health, personal daily life andsecurity, etc. LBS include services to identitfy a location of a person, such asdiscovering the nearest restrant and sort by comments when you want to find someplace to having dinner. Or, it can tell you the store is having a very attractivediscount just10meters behind you. This kind of technique make life easier.This thesis presents a novel approach of inferring the trajectories of movingobjects in a library, conference hall or large shopping mall wherever GPS orcellular localization is not readily available org is deemed too expensive. Oursolution is a distributed one whereby each object records all the other objects itencounters as well as the time of contact and such contact histories collectivelyenable the probabilistic inference of each object’s whereabouts in the past as longas the map of the area is known.