Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “Activity”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,405 records · Page 78
All sourcesNASA NTRSDOE OSTI
NASA NTRSDate not supplied

Long Duration Storage of Liquid Hydrogen via Two-Stage Active Cooling Hardware Characterization and Test Planning

The zero boil-off storage of liquid hydrogen using active cooling (cryocoolers) with a two-stage cooling approach is being investigated by NASA. In interest of advancing the technology to enable extended duration storage for the agency’s future long duration missions, NASA’s Technology Demonstration Mission Program has funded this five-year effort which includes the design, build and testing of a test article to demonstrate this concept. This paper includes discussions of the multiple Cryogenic Fluid Management technologies that were studied under NASA’s Cryogenic Propellant Storage and Transfer project, design of the test article to be demonstrated, then the planned test objectives which include characterization testing of the active cooling system, demonstration of the control system, preliminary testing with liquid nitrogen, and a complete demonstration of zero boil-off storage of liquid hydrogen. The full demonstration will be conducted in the East Test Area at NASA Marshall Space Flight Center and is currently scheduled to begin on October 1st, 2024.

Cryogenic Fluid Management↗
NASA NTRS2024

The Future of Arctic Fires: Leveraging Ongoing Activities, New Efforts, and International Cooperation

Fires in the Arctic region are gaining more attention and driving increased concern from the public, the scientific community, and policymakers. An increasing number of scientific projects, collaboration efforts, media coverage, and policy assessments have been and are being implemented and published regarding this emerging and important wildland fire phenomenon. In short, this increased activity comes from the recognition of increasing fire risk and activity close to, within, and impacting the Arctic. There is a need to integrate these numerous and expanding local, national, and international efforts to avoid redundant and overlapping efforts and to focus resources more efficiently. As a response, this report suggests short and long-term goals to respond to the growing fire risk and fire danger in the Arctic. All efforts call for more integrated international collaboration and greater recognition of the importance for Arctic communities to be collaborators and leaders.

Future↗
NASA NTRS1962

Life Sciences Activities Associated with Project Mercury

Fifteen years of speculation and study concerning the problems of placing man into space flight produced a mass of reports which contemplated the hurdles and suggested solutions needed to permit safe flight. The accumulation of problems occurred in all disciplines. This could have been expected because the area of study was in the unknown, and speculation and calculation were the only methods of attack until flight data could be obtained. The Life Sciences community was as prolific in the identification of potential problem areas as the other scientific disciplines. The arrival of the era of manned space flight offers the opportunity to assess the problems directly and to define what is speculation and what is problem. This paper will discuss two areas of life sciences activities during the Project Mercury program. The first area will review the life-support activities associated with the spacecraft development and the provisions for the astronaut. The second area will present a summarization of the data concerning man's ability to live and work in this new environment and will attempt to present an analysis of the significance of the findings in light of future flights.

Physiological response↗
NASA NTRS1962

THE COMBINATION OF ACTIVE AND PASSIVE SHIELDING

I is conceivable that improved shielding of space vehicles against high-energy charged-particle radiation can be obtained by combining active and passive shielding. Methods of shielding calculations and some preliminary observations pertaining to active-passive shielding are given. An analysis based upon the field of a magnetic dipole indicates that weight savings in bulk shielding can be accomplished.

SPACECRAFT SHIELDING↗
NASA NTRS1964

Inflight crew activities.

In flight crew activities covering detailed flight plan, activities and procedures, checklists and summary

ASTRONAUT PERFORMANCE↗
NASA NTRS1971

Active parallel redundancy for electronic integrator-type control circuits

Circuit extends concept of redundant feedback control from type-0 to type-1 control systems. Inactive channels are slaves to the active channel, if latter fails, it is rejected and slave channel is activated. High reliability and elimination of single-component catastrophic failure are important in closed-loop control systems.

Peterson, R. A.↗
NASA NTRS1972

Comparison of catalyst activity

Reactions of highly active catalysts are compared by allowing temperature of catalyst bed, initially at 77 K, to increase slowly; marked deviation in smooth warming curve denotes temperature at which detectable reaction occurs. The lower the temperature at which reaction commences, the more active the catalyst.

Jennings, T. J.↗
NASA NTRS1972

A magnetic mouse activity meter

Activity meter has been developed using Hall effect devices that record passage of selected groups of magnetically tagged mice. Two small permanent magnets are implanted in belly and back of selected mice and electronic circuits are activated as mice move between cages. System has advantage over tagging, detecting, and identification methods currently used.

Henry, J.↗