Database tomography (DT) is a textual database analysis system consisting o
f two major components: (1) algorithms for extracting multiword phrase freq
uencies and phrase proximities (physical closeness of the multiword technic
al phrases) from any type of large textual database, to augment (2) interpr
etative capabilities of the expert human analyst. DT has been used to deriv
e technical intelligence from a variety of textual database sources, most r
ecently the published technical literature as exemplified by the Science Ci
tation Index (SCI) and the Engineering Compendex (EC). Phrase frequency ana
lysis (the occurrence frequency of multiword technical phrases) provides th
e pervasive technical themes of the topical databases of interest, and phra
se proximity analysis provides the relationships among the pervasive techni
cal themes. In the structured published literature databases, bibliometric
analysis of the database records supplements the DT results by identifying
the recent most prolific topical area authors; the journals that contain nu
merous topical area papers; the institutions that produce numerous topical
area papers; the keywords specified most frequently by the topical area aut
hors; the authors whose works are cited most frequently in the topical area
papers; and the particular papers and journals cited most frequently in th
e topical area papers. This review paper summarizes: (1) the theory and bac
kground development of DT; (2) past published and unpublished literature st
udy results; (3) present application activities; (4) potential expansion to
new DT applications. In addition, application of DT to technology forecast
ing is addressed. (C) 2001 Elsevier Science Inc. All rights reserved.