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R-tree based spatial join is useful because of both its superior performance and the wide spread implementation of R-trees. We present a new R-tree join method called BFRJ (Breadth-First R-tree Join). BFRJ synchronously traverses both R-trees in breadthfirst order while processing join computation one level at a time. At each level, BFRJ creates an(More)
Efficient path computation is essential for applications such as intelligent transportation systems (ITS) and network routing. In ITS navigation systems, many path requests can be submitted over the same, typically huge, transportation network within a small time window. While path precomputation (path view) would provide an efficient path query response,(More)
Efficient path query processing is a key requirement for advanced database applications including GIS (Geographic Information Systems) and ITS (Intelligent Transportation Systems). We study the problem in the context of automobile navigation systems where a large number of path requests can be submitted over the transportation network within a short period(More)
Web Service selection is an important issue in dynamic Web Service composition. The existing approaches are QoS local optimization based. They cannot achieve global constraints and preferences set by user. In general, service selection with QoS global optimization is a NP-complete problem. So, we propose a model of Web Service selection with QoS global(More)
The development of a cost model for predicting the performance of spatial joins has been identified in the literature as an important and difficult problem. In this paper, we present the first cost model that can predict the performance of spatial joins using R-trees. Based on two existing R-trees (join targets), our model first estimates the number of(More)
In this paper, we present an experimental evaluation of graph clustering strategies in terms of their effectiveness in optimizing I/O for path query processing in digital map databases. Clustering optimization is attractive because it does not incurs any run-time cost, and is complimentary to many of the existing techniques in path query optimization. We(More)
Transcriptomics continues to provide ever-more evidence that in morphologically complex eukaryotes, each protein-coding genetic locus can give rise to multiple transcripts that differ in length, exon content and/or other sequence features. In humans, more than 60% of loci give rise to multiple transcripts in this way. Motifs that mediate protein-protein(More)
The emergence of Web services has led to more interest into Web service composition, which is an active area of research. The formidable problem of efficient and effective composition of existing Web services is the subject of much current attention. The study of workflow model is one of the most important parts and a key layer of Web service composition.(More)
Targets with uniform rotational motion may cause migration through cross-range cells during the imaging time, which makes the inverse synthetic aperture radar image smeared. Traditional motion compensation methods hardly work well because it is difficult to estimate the quadratic phase error (QPE) caused by uniform rotational motion efficiently. To solve(More)
Current literature on parallel bulk-loading of R-tree index has the disadvantage that the quality of produced spatial index decrease considerably as the parallelism increases. To solve this problem, a novel method of bulk-loading spatial data using the popular MapReduce framework is proposed. MapReduce combines Hilbert curve and random sampling method to(More)