• 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 ...
    • Nearest Neighbor Algorithms using xBR-Trees 

      Roumelis, G.; Vassilakopoulos, M.; Corral, A. (2011)
      One of the common queries in spatial databases is the (K) Nearest Neighbor Query that discovers the (K) closest objects to a query object. Processing of spatial queries, in most cases, is accomplished by indexing spatial ...