All of DSpace

Browsing by Subject "Spatial query processing"

Now showing items 1-8 of 8

    • An efficient algorithm for bulk-loading xBR+-trees 

      Roumelis G., Vassilakopoulos M., Corral A., Manolopoulos Y. (2018)
      A major part of the interface to a database is made up of the queries that can be addressed to this database and answered (processed) in an efficient way, contributing to the quality of the developed software. Efficiently ...

    • Efficient processing of all-k-nearest-neighbor queries in the MapReduce programming framework 

      Moutafis P., Mavrommatis G., Vassilakopoulos M., Sioutas S. (2019)
      Numerous modern applications, from social networking to astronomy, need efficient answering of queries on spatial data. One such query is the All k Nearest-Neighbor Query, or k Nearest-Neighbor Join, that takes as input ...

    • The K group nearest-neighbor query on non-indexed RAM-resident data 

      Roumelis G., Vassilakopoulos M., Corral A., Manolopoulos Y. (2016)
      Data sets that are used for answering a single query only once (or just a few times) before they are replaced by new data sets appear frequently in practical applications. The cost of buiding indexes to accelerate query ...

    • LB-Grid: An SSD efficient Grid File 

      Fevgas A., Bozanis P. (2019)
      Recent advances in non-volatile memory technology have led to the introduction of solid state drives (SSD). NVMe SSDs are the latest development in flash based solid state drives and they were designed as a means of low ...

    • MapReduce algorithms for the k group nearest-neighbor query 

      Moutafis P., Vassilakopoulos M., García-García F., Corral A., Mavrommatis G., Iribarne L. (2019)
      Given two datasets of points (called Query and Training), the Group (K) Nearest Neighbor (GNN) query retrieves (K) points of the Training dataset with the smallest sum of distances to every point of the Query one. This ...

    • Plane-sweep algorithms for the K Group Nearest-Neighbor Query 

      Roumelis, G.; Vassilakopoulos, M.; Corral, A.; Manolopoulos, Y. (2015)
      One of the most representative and studied queries in Spatial Databases is the (K) Nearest-Neighbor (NNQ), that discovers the (K) nearest neighbor(s) to a query point. An extension that is important for practical applications ...

    • SliceNBound: Solving closest pairs and distance join queries in apache spark 

      Mavrommatis G., Moutafis P., Vassilakopoulos M., García-García F., Corral A. (2017)
      The (K) Closest-Pair(s) Query, KCPQ, consists in finding the (K) closest pair(s) of objects between two spatial datasets. Recently, several systems that enhance Apache Spark with spatial-awareness have been presented, ...

    • The xbr+-tree: An efficient access method for points 

      Roumelis G., Vassilakopoulos M., Loukopoulos T., Corral A., Manolopoulos Y. (2015)
      Spatial indexes, such as those based on Quadtree, are important in spatial databases for efficient execution of queries involving spatial constraints. In this paper, we present improvements of the xBR-tree (a member of the ...