@techreport{TR-IC-98-34,
  number = {IC-98-34},
  author = {Mario A. Nascimento and Jefferson R. O. Silva and Yannis Theodoridis},
  title = {Access Structures for Moving Points},
  month = {October},
  year = {1998}, 
  institution = {Institute of Computing, University of Campinas},
  note = {In English, 23 pages.
    \par\selectlanguage{english}\textbf{Abstract}
      Several applications require management of data which is spatially 
      dynamic, e.g., tracking of battle ships or moving cells in a blood 
      sample.  
    \par
      The capability of handling the temporal aspect, i.e., the history 
      of such type of data, is also important.  This paper presents and 
      evaluates three temporal extensions of the R-tree---the 3D R-tree, 
      the $2+3$ R-tree and the HR-tree---which are capable of indexing 
      spatiotemporal data.  Our experiments have shown that while the 
      HR-tree was the larger structure, its query processing cost was over 
      50$\%$ smaller than the ones yielded by the 3D R-tree and the $2+3$ 
      R-tree.  Also compared to the (non-practical) approach of storing 
      one R-tree for each of the spatial database states it offered the
      same query processing cost, saving around one third of storage space.
  }
}