Research On Location Dependent Query In Mobile Computing Environment

With the advances in wireless communication technology, users can access the information they need at anytime, anywhere. Mobile computing is a research hot point currently. In mobile computing environment, users need to access applications and data that related to their geographical position, seeking information about unfamiliar places or local lifestyle data. Location dependent query in mobile environment has become the new research direction of mobile computing.Firstly, this dissertation introduces the concept, makeup and the characteristics of mobile computing, gives the concept of Location Dependent Data (LDD) and Location Dependent Query (LDQ) respectively. Then it discusses the processing of LDQ, location translation, and the location granularities adjusting problems.Secondly, it introduces the key technologies of LDQ-------mobilemanagement mechanism of Mobile IP, and devises new mobile management mechanism of Mobile IP based on IPv6.Thirdly, it introduces the location management of mobile objects of LDQ in mobile computing, and devises an algorithm to analyze locations of LDQ based on the analysis of the massive Location Dependent Data, named "Global Analysis of Location (GAL)" .Fourthly, it proposes an approximate answers model using generalized databases and the concept hierarchies based on location for mobile computing query processing. In a mobile computing environment, because of characteristics such as availability, connectivity, low-band width, data quality and usage cost, users may not obtain perfect answers to their queries within an acceptable time. However, within known limits of correctness and precision, an approximate answer may suffice for some mobile users. Generalized databases are smaller than...