eSPAK: Top-K Spatial Keyword Query Processing in Directed Road Networks

Given a query location and a set of query keywords, a top-k spatial keyword query rank objects based on the distance to the query location and textual relevance to the query keywords. Several solutions have been proposed for top-k spatial keyword queries in Euclidean space. However, few algorithms study top-k keyword queries in undirected road networks where every road segment is undirected. Even worse, insufficient attention has been given to the processing of keyword queries in directed road networks where each road segment has a particular orientation. Therefore, in this paper, we present an algorithm called eSPAK that can efficiently answer the top-k spatial keyword queries in directed road networks. Our experimental results demonstrate that eSPAK significantly outperforms conventional solution in terms of query processing cost.