Engineering topics

Lehmann, J.

Publications and source records attributed to Lehmann, J..

7 records

NASA NTRS1985

Parallel processor programs in the Federal Government

In 1982, a report dealing with the nation's research needs in high-speed computing called for increased access to supercomputing resources for the research community, research in computational mathematics, and increased research in the technology base needed for the next generation of supercomputers. Since that time a number of programs addressing future generations of computers, particularly parallel processors, have been started by U.S. government agencies. The present paper provides a description of the largest government programs in parallel processing. Established in fiscal year 1985 by the Institute for Defense Analyses for the National Security Agency, the Supercomputing Research Center will pursue research to advance the state of the art in supercomputing. Attention is also given to the DOE applied mathematical sciences research program, the NYU Ultracomputer project, the DARPA multiprocessor system architectures program, NSF research on multiprocessor systems, ONR activities in parallel computing, and NASA parallel processor projects.

Schneck, P. B.↗

NASA NTRS1983

The Shuttle Environment Workshop

Results of shuttle environmental measurement programs were presented. The implications for plasma, infrared and ultraviolet experiments were discussed. The prelaunch environmental conditions, results of key environmental measurements made during the flights of STS 1, 2, 3, 4, and postlanding environmental conditions were covered.

Lehmann, J.↗

NASA NTRS1983

Environmental Measurements Session summaries

Emphasis was placed on data from payloads flown on the subject flights including results from the Induced Environment Contamination monitor (IECM). Brief summaries of the vibroacoustics, loads, electromagnetic and thermal aspects of the environment, as derived from Shuttle system measurements, were presented primarily to indicate where the environment was different than observed and, therefore, where specification changes may be forthcoming. In addition, brief summaries of two somewhat unexpected effects, the vehicle glow and interaction between the low Earth environment and Shuttle payload by materials were presented as an aid in interpreting other environmental data. Papers for each payload/experiment involved in Shuttle flights were presented essentially in flight related chronological order. A significant portion of time was allocated for presentation of IECM data since this payload was flown on STS-2, STS-3, and STS-4 and, therefore, represents the largest data base relative to the contamination environment. Summaries of papers are presented.

Lehmann, J.↗

NASA NTRS1983

Report of the infrared, ultraviolet and space plasma panels

The status of the payload bay and the needs of infrared, ultraviolet and space plasma experiments were discussed. Those measurements important in each area were reviewed. Issues of concern and how these environmental conditions might impact experiments were considered. Several common issues were revealed, and recommendations were made.

Lehmann, J.↗

NASA NTRS1983

Future outlook and comments

The events of the workshop panel sessions are summarized and a synopsis of the future of the shuttle and the shuttle environment is given. Comments and projections in a number of areas addressed include: environmental measurements, contamination effects, orbiter constraints on deployable payloads, documentation and environmental information, ultraviolet experiments, infrared experiments, plasma experiments, and shuttle lidar.

Lehmann, J.↗

NASA NTRS1982

The Shuttle Environment Workshop, executive summary and workshop procedures

One of the main experimental monitors used to determine the environment in the payload bay was the Induced Environment Contamination Monitor. This package of instruments has made environmental measurements during STS flights with a high degree of success. This has shown that the shuttle environment is relatively free of contaminants, except for special instances of increased abundance of methane, water vapor and particulates. Results of these measurements are rapidly becoming more available. In establishing the Shuttle Environment Workshop, the findings were shared with scientific experimenters, users and other individuals who need to know what the Shuttle is like and what experimenters may expect in the payload bay. The Workshop was centered around results obtained from the environmental measurements made on the Shuttle. The program agenda for the workshop is given. The procedures and flow of communications for the workshop are indicated.

Lehmann, J.↗

NASA NTRS1973

Remote sensors - Prospects and limitations

Review of the history, present status, and future prospects and limitations of remote sensing systems for satellite-based earth resources surveys. The objectives and special areas of interest of ongoing sensor development experiments are summarized, and the measurement and performance goals of current potential sensor research is discussed.

Lehmann, J.↗