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-i6 The timing problem in general does not seem difficult; method [OCRerr]) in particular, could offer almost instantaneous response even with present- day time-sharing system supervisors. Once the answers are known, they must be communicated to the user. Probably the best system would be to present a microfilm reel rwz[OCRerr]ber and frame number, with reference to a reader (preferably reader/printer) located next to the console. For sufficiently large sums of money one could no doubt buy a microfilm reader which could be spaced to the correct frame by the computer, but this would probably cost too much. Also, the microfilm device alone would be valuable and ought to be usable without the computer. The advantage of microfilm output, which can present an iaage of the actual document to the user immediately, is that users are likely to judge the system largely by the elegance of the output. Permitting immediate reference to the answers without leaving onets chair does sound very attractive. However, one must consider the possibility that microfilm equipment will not be available, or that some customer is using a console not in the library, and not close to any collection of journals. In this case the system must depend on its own input-output devices, and it will probably be better to store in the data store a list of the titles, authors, and journals of all articles which can be presented. In fact, microfilm readers may be sufficiently slow to make this desirable under any circumstances. About 1000 8 bits per document should suffice for this data, or 2.5xl0 bits. This takes up about one data cell section. Storing the entire abstract is probably too expensive, and would also in all probability be too slow to type out. No timing problems arise in connection with the production of output,