An Index Structure for Efficient k-NN Query Processing in Location Based Services

Many studies on index structures for k-NN query processing have been done in Location Based Services(LBS). However, they are not suitable for the moving objects because their update costs are so expensive due to the frequent location updates of the moving objects. In this paper, we propose Incremental Search R-tree(ISR-tree) that processes k-NN queries efficiently in the environment with static objects and moving clients. In ISR-tree, the leaf-nodes maintain the entries pointing to their relevant neighbor nodes and the entries help to find the neighbor leaf-nodes without visiting internal nodes when k-NN queries are processed. We prove the superiority of ISR-tree through the comparison with previous works. As a result, since ISR-tree saves the costs to visit internal nodes, it significantly improves the performance over the existing index structure.