In 2001 TRB published NCHRP Report 450: Transportation Research Thesaurus and User's Guide. The primary purpose of the Transportation Research Thesaurus (TRT) is to provide a common vocabulary for producers and users of TRB's TRIS database. In addition to TRB, other organizations are using the TRT in a variety of applications and platforms: the National Transportation Library Digital Library catalog, the catalogs of academic and department of transportation libraries, and the web-based catalogs of various institutions. Moreover, the TRT vocabulary is mapped to other standard vocabularies, including the Library of Congress Subject Headings (LCSH) and the International Transport Research Documentation Thesaurus. The TRT now contains over 10,000 terms as well as scope notes and “used for terms”.
The Transportation Research Thesaurus was developed in accordance with the principles of the Guidelines for the Construction, Format, and Management of Monolingual Thesauri (ANSI/NISO Z39.19-1993), an American National Standard developed by the National Information Standards Organization and approved August 30, 1993, by the American National Standards Institute. The standard specifies equivalence (synonymous), hierarchical, and associative relationships among terms and recommends print and screen formats to show these relationships.
In FY2006, NCHRP Project 20-70 funded the development of web access to the TRT on the TRB website as well as improvements to the technology that supports use of the TRT by TRIS indexers. Both tasks were successfully completed and implemented.
Although the technical improvements have been significant, users would benefit from the addition of term definitions. Providing more information to those indexing or defining their reports and resources would allow for more consistent use of vocabulary across repositories and thus improve access to like information. Definitions would also support the user who is working outside his/her specialization.
One source of definitions already identified for addition to the TRT is AASHTO's draft multi-modal glossary, which was developed under NCHRP Project 20-7/Task 153. The AASHTO Glossary contains about 3,000 definitions of terms related to transportation. Additional authoritative sources of definitions should be identified and leveraged to improve and enhance the TRT.
The objective of the research is to expand the TRT to include definitions of terms that exist in both the TRT and the AASHTO glossary and/or other authoritative sources.