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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.

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At least 1,747 records · Page 97
All sourcesNASA NTRSDOE OSTI
NASA NTRS1979

Development of space manufacturing systems concepts utilizing lunar resources

Results of a NASA sponsored study to evaluate the merits of constructing solar power satellites using lunar and terrestrial resources are reviewed. Three representative lunar resources utilization (LRU) concepts were developed and compared with a previously designed earth baseline concept, and major system hardware elements as well as personnel requirements were defined. LRU for space construction was shown to be competitive with earth baseline approach for a program requiring 10 to the 5th metric tons per year of completed satellites. Results also indicated that LRU can reduce earth launched cargo requirements to less than 10% of that needed to build satellites exclusively from earth materials, with a significant percentage of the reduction due to the use of liquid oxygen derived from lunar soil. A concept using the mass driver to catapult lunar material into space was found to be superior to the other LRU logistics techniques investigated.

Bock, E. H.↗
NASA NTRS1979

Utilization of 100 mb midlatitude height fields as an indicator of sampling effects on total ozone variations

Midlatitude 100-mb height fields are employed to determine the effects of ground based sampling locations on measurements of variations in the total ozone content of the atmosphere. The precision of the zonal average heights computed by the technique of Angell and Korshover (1978) from data over ozone sampling areas at 50 deg N is compared to the zonal average computed from the entire data set. Linear regressions of ozone contents determined by an analysis of backscatter UV satellite data with respect to 100 mb heights are utilized to transform zonal differences in height to ozone levels. The zonal average total ozone sampling error is found to be on the order of 2% for midlatitudes of the Northern hemisphere, indicating that the general shape of ozone trends determined by ground-based observations appears to be real and the increase of ozone from the mid-1960's to the early 1970's may be greater than previously suggested.

Miller, A. J.↗
NASA NTRS1979

STS utilization planning

The paper shows how NASA plans to utilize the Shuttle to carry a wide variety of payloads. Topics covered include: Shuttle Transportation System (STS) description and capabilities, payload integration and manifesting payload business today, and NASA-JSC user services. Consideration is given to the flight assignment process and flight manifest which is a listing of flights with their attendant launch dates, payload names, days on-orbit, altitude, inclination, and crew required. Additional data such as weight, center of gravity, payload-on-orbit capability, and launch windows are checked to see if the manifest is still valid. The STS traffic model is described along with the small self-contained payloads.

Bauch, G. T.↗
NASA NTRS1979

The utilization of abelian point group symmetry in the graphical unitary group approach to the calculation of correlated electronic wavefunctions

A procedure is described for the utilization of abelian point group symmetry in the graphical unitary group approach (GUGA) to calculations of correlated electronic wavefunctions. The procedure is based on a recursively computed set of symmetry dependent counting indices, and results in the separate numbering, without gaps, of the Gelfand states (configuration functions) belonging to each symmetry species

Shavitt, I.↗
NASA NTRS1979

A program for calculating load coefficient matrices utilizing the force summation method, L218 (LOADS). Volume 1: Engineering and usage

The LOADS program L218, a digital computer program that calculates dynamic load coefficient matrices utilizing the force summation method, is described. The load equations are derived for a flight vehicle in straight and level flight and excited by gusts and/or control motions. In addition, sensor equations are calculated for use with an active control system. The load coefficient matrices are calculated for the following types of loads: translational and rotational accelerations, velocities, and displacements; panel aerodynamic forces; net panel forces; shears and moments. Program usage and a brief description of the analysis used are presented. A description of the design and structure of the program to aid those who will maintain and/or modify the program in the future is included.

Miller, R. D.↗
NASA NTRS1977

Analysis of metabolic energy utilization in the Skylab astronauts

Skylab biomedical data regarding man's metabolic processes for extended periods of weightlessness is presented. The data was used in an integrated metabolic balance analysis which included analysis of Skylab water balance, electrolyte balance, evaporative water loss, and body composition. A theoretical analysis of energy utilization in man is presented. The results of the analysis are presented in tabular and graphic format.

Leonard, J. I.↗
NASA NTRS1979

Results of a utility survey of the status of large wind turbine development

Wind energy conversion systems were surveyed from a utility viewpoint to establish the state of the art with regard to: (1) availability of the type of machines; (2) quality of power generation; (3) suitability for electrical grid; (4) reliability; and (5) economics. Of the 23 designs discussed, 7 have vertical axis wind turbines, 9 have upwind horizontal axis turbines, and 7 have downwind horizontal axis turbines.

Watts, A.↗
NASA NTRS1979

Simulation studies of multiple large wind turbine generators on a utility network

The potential electrical problems that may be inherent in the inertia of clusters of wind turbine generators and an electric utility network were investigated. Preliminary and limited results of an analog simulation of two MOD-2 wind generators tied to an infinite bus indicate little interaction between the generators and between the generators and the bus. The system demonstrated transient stability for the conditions considered.

Gilbert, L. J.↗
NASA NTRS1980

Space construction and utility distribution

Technology advancement to effect an orderly development program leading to construction of space platforms was defined, in a program that utilized a viable platform and service module concept with concise OSS/OAST mission and payload models. Consideration was given to concepts for alternate platform servicing of the payloads described in the model. Using the baseline configuration, issues pertinent to platform development as well as orbit emplacement and operation and on orbit construction methodology were analyzed. These analyses provided the following data: (1) payload definitions and installation options; (2) identified structural and subsystems options; (3) developed integrated platform system concepts; and (4) identified technology deficiencies and recommended technology development timelines.

Bloom, K. A.↗
NASA NTRS1980

A digitally implemented communications experiment utilizing the communications technology satellite, Hermes

Developments which will reduce the costs associated with the distribution of satellite services are considered with emphasis on digital communication link implementation. A digitally implemented communications experiment (DICE) which demonstrates the flexibility and efficiency of digital transmission of television video and audio, telephone voice, and high-bit-rate data is described. The utilization of the DICE system in a full duplex teleconferencing mode is addressed. Demonstration teleconferencing results obtained during the conduct of two sessions of the 7th AIAA Communication Satellite Systems Conference are discussed. Finally, the results of link characterization tests conducted to determine (1) relationships between the Hermes channel 1 EIRP and DICE model performance and (2) channel spacing criteria for acceptable multichannel operation, are presented.

Jackson, H. D.↗
NASA NTRS1979

A study of the potential impacts of space utilization

Because the demand for comprehensive impact analysis of space technologies will increase with the use of space shuttles, the academic social sciences/humanities community was surveyed in order to determine their interests in space utilization, to develop a list of current and planned courses, and to generate a preliminary matrix of relevant social sciences. The academic scope/focus of a proposed social science space-related journal was identified including the disciplines which should be represented in the editorial board/reviewer system. The time and funding necessary to develop a self-sustaining journal were assessed. Cost income, general organizational structure, marking/distribution and funding sources were analyzed. Recommendations based on the survey are included.

Cheston, T. S.↗
NASA NTRS1980

Federal policies to promote the widespread utilization of photovoltaic systems. Supplement: Review and critique

Review comments of the Congressional report entitled 'Federal Policies to Promote the Widespread Utilization of Photovoltaic Systems' are presented. Responses to the review comments by the Jet Propulsion Laboratory, preparer of the Congressional report, are also presented. The Congressional report discussed various issues related to promoting the deployment of photovoltaic systems through the Federal Photovoltaic Program. Various program strategies and funding levels were examined.

Smith, J. L.↗
NASA NTRS1980

Simulator results of an F-14A airplane utilizing an aileron-rudder interconnect during carrier approaches and landings

A piloted simulator study was conducted to evaluate an aileron rudder interconnect (ARI) control system for the F-14A airplane in the landing configuration. Effects on pilot performance and handling characteristics were investigated. Two ARI configurations were tested and compared to the standard F-14 fleet control system. A nonlinear aerodynamic model of the F-14 was used in conjunction with a six degree of freedom motion base simulator. The evaluation task, which utilized three subject pilots, consistent of a night carrier approach and landing. Both ARI configurations produced improved pilot performance and pilot ratings when compared to the standard control system. Sideslip due to adverse yaw as considerably reduced by the ARI systems and heading control was more stable and precise. Lateral deviation from centerline was reduced during the approach and lateral touchdown dispersion on the carrier deck was reduced with the ARI control systems.

Kelly, W. W.↗
NASA NTRS1980

Orbiter electrical equipment utilization baseline

The baseline for utilization of Orbiter electrical equipment in both electrical and Environmental Control and Life Support System (ECLSS) thermal analyses is established. It is a composite catalog of Space Shuttle equipment, as defined in the Shuttle Operational Data Book. The major functions and expected usage of each component type are described. Functional descriptions are designed to provide a fundamental understanding of the Orbiter electrical equipment, to insure correlation of equipment usage within nominal analyses, and to aid analysts in the formulation of off-nominal, contingency analyses.

Source record↗
NASA NTRS1979

A 4-W 56-dB gain microstrip amplifier at 15 GHz utilizing GaAs FET's and IMPATT diodes

Performance results and design considerations are presented for an all solid-state Ku-band power amplifier which is feasible for use in PM communication systems for airborne or spacecraft transmitter applications. A six-stage GaAs FET preamplifier and a driver and balanced power amplifier utilizing GaAs IMPATT diodes operating in the injection locked oscillator mode are discussed. For high power and efficiency Schottky-Read IMPATT's with low-high-low doping profiles are employed. For improved reliability the IMPATT's incorporate a TiW barrier metallization to retard degradation of the IMPATT's. Results of accelerated life testing of the IMPATT devices are also presented.

Sokolov, V.↗
NASA NTRS1980

An automated approach to design of solid rockets utilizing a special internal ballistics model

A pattern search technique is presented, which is utilized in a computer program that minimizes the sum of the squares of the differences, at various times, between a desired thrust-time trace and that calculated with a special mathematical internal ballistics model of a solid propellant rocket motor. The program is demonstrated by matching the thrust-time trace obtained from static tests of the first Space Shuttle SRM starting with input values of 10 variables which are, in general, 10% different from the as-built SRM. It is concluded that an excellent match is obtained.

Sforzini, R. H.↗