Moving K-Nearest Neighbor Query over Obstructed Regions

In recent years, there has been a growing need for location-based services (LBS), ranging from resource tracking to personal life assistance. The Moving k Nearest Neighbor (MkNN) query is a main problem in the LBS area, which retrieves the top k nearest neighbors while the query consumer moves. Considerable attention is attracted to this query type and a large number of studies are proposed recently. Most of these studies focus on ideal Euclidean plane where any two points are visible. In this paper, we propose a method to process MkNN queries in areas with obstacles, which is more realistic. We propose the obstacle-free safe region (OSR) concept within which a query point has the same kNN. No additional processing is required when the query consumer moves inside one OSR. Several novel properties are also introduced and employed in our efficient MkNN processing algorithm. Our experimental results show that our approach handles the MkNN queries with high accuracy and works efficiently.