Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.
Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.
OCR for page 329
329 used cleverly with carefully planned observing programs, is probably adequate for both applications, although high- bandwidth lines are extremely desirable. With a 56-kbps line, it may prove cost-effective to operate telescopes from remote locations in some cases. For example, the University of California is investigating the possibility of operating a proposed 10-m telescope, located on Mauna Kea, from a control center in California. If remote operation saves only a few round trips per month between Hawaii and California, a net cost savings will be achieved. In the case of the second application, the Panel believes that an observatory operating its tele- scopes with remote observer participation must take responsibility for the terminal at the observer's end of the data link. The costs of such a scheme would there- fore be substantially greater than the costs of the communication service alone and will probably prohibit the implementation of this concept in the 1980's. I X. SPECIALI ZED ARCHITECTURES The Panel investigated the possibility that specialized computer architectures might lead to dramatic improve- ments in astronomical computing. For example, one might imagine a cubical n X n X n array of microprocessors, each able to transfer data to and from its six nearest neighbors and all synchronized by a master oscillator. Such an array would seem to be ideal for some kinds of hydrodynamical calculations and would reduce the computa- tion time by a factor of n3 since n3 operations are performed in parallel. If the top and bottom, left and right, and front and back sides of the array were con- nected, the architecture could be adapted to N-body calculations with n3 particles (one per processor). There are, in fact, several specialized architectures being investigated and/or implemented. NASA/Goddard Space Flight Center is developing the Massively Parallel Proces- sor (MPP), which will contain a 128 X 128 array of proces- sors, each connected to its nearest neighbors on the top, bottom, left, and right. Each processor will be capable of performing only simple functions. The MPP is intended to be used for pipeline processing of Landsat images. It is an interesting development in that the physics of the problem is embodied in the computer architecture. NASA/Ames is developing a specialized computer to be used in hydrodynamic calculations. The emphasis here is