Search (2 results, page 1 of 1)

  • × author_ss:"Bell, T.C."
  • × language_ss:"e"
  • × type_ss:"a"
  • × year_i:[1990 TO 2000}
  1. Wittan, I.H.; Bell, T.C.; Nevill, C.G.: Indexing and compressing full-text databases for CD-ROM (1991) 0.02
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    Abstract
    CD-ROM is an attractive delivery vehicle for full text databases. Large storage capacity and low access speed, carefully designed indexing structures, including a concordance, are necessary to enable the text to be retrieved efficiently. However, the indexes are sufficiently large that they tax the ability of the main store to hold them when processing queries. The use of compression techniques can substantially increase the volume of text that a disc can accomodate, and substantially decrease the amount of primary storage needed to hold the indexes. Describes a suitable indexing mechanism, and its compression potential using modern compression methods. It is possible to double the amount of text that can be stored on a CD-ROM disc and include a full concordance and indexes as well
  2. Bell, T.C.; Moffat, A.; Nevill-Manning, C.G.; Witten, I.H.; Zobel, J.: Data compression in full-text retrieval system (1993) 0.01
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    Abstract
    When data compression is applied to full-text retrieval systems, intricate relationships emerge between the amount of compression, access speed, and computing resources required. We propose compression methods, and explore corresponding tradeoffs, for all components of static full-text systems such as text databases on CD-ROM. These components include lexical indexes, and the mein text itself. Results are reported on the application of the methods to several substantial full-text databases, and show that a large, unindexed text can be stored, along with indexes that facilitate fast searching, in less than half its original size - at some appreciable cost in primary memory requirements