Chuanwen Li

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The moving k nearest neighbor query, which computes one's k nearest neighbor set and maintains it while at move, is gaining importance due to the prevalent use of smart mobile devices such as smart phones. Safe region is a popular technique in processing the moving k nearest neighbor query. It is a region where the movement of the query object does not(More)
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(More)
We revisit the moving k nearest neighbor (MkNN) query, which computes one's k nearest neighbor set and maintains it while at move. Existing MkNN algorithms are mostly safe region based, which lack efficiency due to either computing small safe regions with a high recomputation frequency or computing larger safe regions but with a high cost for each(More)
The moving $$k$$ k nearest neighbor (MkNN) query has been studied extensively. Most of the studies assume no obstacle in the space. However, obstacles like rivers, buildings and private properties commonly exist in the space, and one may need to go around the obstacles to reach his/her nearest neighbors. In this paper, we study the moving kNN query in(More)
With extensive applications of wireless sensor networks (WSNs), a WSN system with single function such as sea-monitoring and accident succor is expected to supply much more abilities for effective periodic queries or ad hoc queries, because some applications require real-time queries since the results should be returned before deadlines. Meanwhile,(More)
BACKGROUND Accumulating evidence indicates that stroke risk may be increased following herpes zoster. The aim of this study is to perform a meta-analysis of current literature to systematically analyze and quantitatively estimate the short and long-term effects of herpes zoster on the risk of stroke. METHODS Embase, PubMed and Cochrane library databases(More)