Work Items工作的目

1、data management in mobile computingkien a. huaschool of eecsuniversity of central floridaapplications location-based services ubiquitous computing traffic and incident management environmental monitoring mobile communicationchallenge traditional and spatial databases cannot handle the rate of locati

2、on update from moving objects processing range-monitoring query what is range-monitoring query? retrieve mobile objects in a spatial region, and continuously monitor the population in the arearange-monitoring queriesaq2q1bcfderange-monitoring queriesaq2q1bcfde how to minimize location updates? each

3、update involves mobile communication costs and server processing costs how to minimize monitoring update cost? query results keep changing research issuesq1q5q2q4safe regionsq3circular safe regionrectangularsafe regionaproblems with safe regions computing a safe region takes from o(n) to o(n log3 n)

4、 adding a new query requires re-computation of safe regions for all objectshow to provide accurate query results, and real-time updates?challengeproposed: monitoring-query managementq1q2q7q6q3q5q4aresident domain given an objects position p and its processing capability n, its resident domain should

5、computing a resident domain contain position p, and be as large as possible, but contain no more than n queriesdomain and query decompositionq1q4q2q3r1r42r21r31r22r41domain and query decompositionq1q4q2q3r1r42r21r31r22r41adomain and query decompositionq1q4q2q3r1r42r21r31r22r41abinary partitioning tr

6、ee (bp-tree)dddomain nodedata nodedd1d1d2d2binary partitioning tree (bp-tree)d1d1d2d21d22d21d22dbinary partitioning tree (bp-tree)mobile communication cost051015202530102030405060708090100number of messages sent by mobile objects (millions)number of monitoring queries (thousands)mqmsafe regionserver processing cost0.11101001000102030405060708090100number of index nodes accessed (millions)number of monitoring queries (thousands)mqmsafe regionsignificant and impact of mqm mqm is highly scalable, in terms of