Cray X-MP/48


The original machine at Pittsburgh Supercomputing Center, the Cray X-MP/48 could perform up to 840 million arithmetic operations every second.  It had eight million words of memory and was connected to sixteen DD-49’s.  It was also equipped with a 128 million word SSD (solid state storage device).  This SSD could transfer data to the main processor 100 times faster than the disks, and effectively expanded the Cray’s memory to 128 million words. The Cray had four independent processors, each of which had fourteen independent functional units.

 The X-MP was in use from 1986 to 1989.




 Designing Air Quality Control Strategies for Los Angeles

Gregory J. McRae, Armistead G. Russell, and Jana B. Milford

Carneigie Mellon University

This study that was undertaken at the Pittsburgh Supercomputing Center indicated why previous air quality control tactics had failed, and also suggested an alternative strategy that offered the possibility of approaching EPA compliance within the Los Angeles area.  Some conclusions from the study included:

  • It was found that the amount of ozone in the atmosphere does not necessarily decrease if particular emissions are reduced.  It was shown that the exact relationships between amount of pollution and the level of emissions was so complicated that, in some cases, strategies for reducing particular pollutants could actually cause air quality to deteriorate in outlying areas.
  • Found that the EPA’s concentration on hydrocarbon control alone was inadequate.
  • If alternate fuel like methanol were substituted for gasoline in Los Angeles vehicles, substantial reductions in oxidant and particulate pollution could be achieved.

Drug-Protein Binding

Stephen H. Fleischman and Charles L. Brooks, III

Carnegie Mellon University

The goal of this research was to increase understanding of the complicated interactions that determine drug-protein binding to the point of rational predication of drug design changes.  Such a process is quite complicated, however, involving desolvation (the stripping away of solvating water) of the drug molecule and parts of the protein.  The binding of trimethoprim (TMP) and its derivatives to the enzyme dihydrofolate reductase from chicken was what was being studied.  This system was chosen for study because of its pharmacological importance in the treatment of bacterial maladies and its potential as an anti-cancer agent. 

Sinking Satellites of Spiral Galaxy Systems

Peter J. Quinn, Space Telescope Science Institute, Baltimore

Lars Hernquist, Princeton Institute for Advanced Studies

With the discovery of galaxies came many questions, such as how they form and evolve, when in the history of the universe did they first appear, and what are the differences among different galaxies.  Using the CRAY machine as a laboratory, these scientists were able to conduct experiments, uncover new dynamical processes and come closer to understanding the birth and life cycles of the building blocks of the universe, the galaxies.