Search

The number of searched nodes and the computation time in an index should be minimized for optimizing the processing cost of the nearest neighbor query. The Measurement of search distance considered a circular location property of objects is required to accurately select the nodes which will be searched in the nearest neighbor query. In this paper, we propose the processing method of the nearest neighbor query be considered a circular location property of object where the search space consists of a circular domain and show its performance by experiments. The proposed method uses the circular minimum distance and the circular optimal distance which are the search measurements for optimizing the processing cost of the nearest neighbor query.

To increase the retrieval performance in spatial and multimedia database systems, it is required to develop spatial indexing methods considering the spatial locality. The spatial locality is related to the location property of objects. Most spatial indexing methods, however, were not considered the circular location property of objects. In this paper, we propose a dynamic spatial index structure, called CR*-tree. It is a new spatial index structure to support the circular location property of objects in which a search space is organized with the circular and linear domains. We include the performance test results that verify this advantage of the CR*-tree and show that the CR*-tree outperforms the R*-tree.