Engineering topics

Likens, William C.

Publications and source records attributed to Likens, William C..

3 records

NASA NTRS1991

The Life Support Database system

The design and implementation of the database system are described with specific reference to data available from the Build-1 version and techniques for its utilization. The review of the initial documents for the Life Support Database is described in terms of title format and sequencing, and the users are defined as participants in NASA-sponsored life-support research. The software and hardware selections are based respectively on referential integrity and compatibility, and the implementation of the user interface is achieved by means of an applications-programming tool. The current Beta-Test implementation of the system includes several thousand acronyms and bibliographic references as well as chemical properties and exposure limits, equipment, construction materials, and mission data. In spite of modifications in the database the system is found to be effective and a potentially significant resource for the aerospace community.

Likens, William C.↗

NASA NTRS1991

Analysis of an initial lunar outpost life support system preliminary design

A preliminary design of a life-support system (LSS) was developed as part of an ongoing comprehensive trade study of advanced processor technologies and system architectures for an initial lunar outpost. The design is based on a mission scenario requiring intermittent occupation of a lunar-surface habitat by a crew of four. It incorporates physiochemical process technologies that were considered for Space Station Freedom. A system-level simulation model of the design was developed to obtain steady-state material balances for each LSS processor. The mass-flow rate predictions were used to obtain estimates of the LSS mass, volume, and power consumption by means of processor-sizing correlations that were extrapolated from Space Station Freedom processor designs. The results were used to analyze the impacts of varying crew size, mission duration, processor-operation strategy, and crew-cabin loads on the LSS mass, average power consumption, volume, periodic resupply mass, and waste-accumulation rates. The merits of the design were quantified relative to an open-loop LSS, and the implications of this assessment for future LSS research and technology development were identified.

Ballin, Mark G.↗

NASA NTRS1988

A preliminary investigation of communication techniques for local and remote access to image databases

A software technique which allows users to examine images remotely while minimizing transmission time, is discussed. The technique provides a browsing capability, making it possible to roam over larger images, to zoom to various resolution levels, and to specify subregions of interest in the image to display at full resolution. The software permits analysts to remotely submit images for processing and to review the processing result. The capabilities of the technique under varying conditions and the speed at which imagery can be displayed over direct connect serial lines are discussed and examples of the imagery at various levels of resolution are presented.

Ma, Mathias↗