ISR11 Design Consideration for Time Shared Automatic Documentation Centers chapter M. E. Lesk Harvard University Gerard Salton Use, reproduction, or publication, in whole or in part, is permitted for any purpose of the United States Government. x-6 the beginning of the project; requests and new documents are looked up as they arrive. When new documents are added, they are also studied to see if the dictionaries are still reasonably up-to-date. Experience shows, and c[OCRerr]nmon sense would indicate, that provision for repeated or iterated searches is necessary. Any system is certain to exhibit some peculiarities, derived from the document collection if fr[OCRerr] nothing else, and requests must be adjusted to them. This has already been noted in the experimental system. The following may represent a possible outline of the steps involved in processing a request. 1) The user approaches a console, probably located in a library, that is attached to a large time-shared computer. He identifies himself and provides whatever accounting information is required by the system operators, and is then placed in contact with the retrieval programs. 2) The user types his request in natural few rules designed to insure clarity. of his need which would be clear to a for the computer. English, observing only a Basically, any statement librarian should suffice 3) His request is looked up in a thesaurus and its associated phrase dictionary, and the adjusted request image is prepared for searching. 4) The request is now matched against documents from the reference collection, using an efficient but accurate search strategy, and those documents relevant to the request are selected by the computer. 5) Within a time interval measured in seconds, an answer is provided. Depending on the hardware available, this might be a document accession nimiber, a bibliographic citation, a citation plus the document title, a citation plus the document abstract, a microfilm reel and frame mmber for the library microfilm room, or a picture