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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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The possibilities are considered that modern electronics and engineering have to offer the individual with a damaged or disordered nervous system, especially the blind person. Discussed are the incidence and principal causes of blindness, past research activities, and a capsule review of some of the more interesting programs designed to provide the blind with the ability to be mobile in their environment and to read printed matter.
The impact of 'fourth generation' computers (STAR 100 or ILLIAC 4) on NASTRAN is considered. The desired characteristics of large programs designed for execution on 4G machines are described.
A precision trajectory program has been developed to serve as a test bed for geocentric orbit raising steering laws. The steering laws to be evaluated have been developed using optimization methods employing averaging techniques. This program provides the capability of testing the steering laws in a precision simulation. The principal system models incorporated in the program are described, including the radiation environment, the solar array model, the thrusters and power processors, the geopotential, and the solar system. Steering and array orientation constraints are discussed, and the impact of these constraints on program design is considered.
The cloud data bank, the 4-D atmospheric model, and a set of computer programs designed to simulate meteorological conditions for any location above the earth are described in turns of space vehicle design and simulation of vehicle reentry trajectories. Topics discussed include: the relationship between satellite and surface observed cloud cover using LANDSAT 1 photographs and including the effects of cloud shadows; extension of the 4-D model to the altitude of 52 km; and addition of the u and v wind components to the 4-D model of means and variances at 1 km levels from the surface to 25 km. Results of the cloud cover analysis are presented along with the stratospheric model and the tropospheric wind profiles.
A possible measurement program designed to obtain the information requisite to determining the feasibility of airborne and/or satellite-borne LDV (Laser Doppler Velocimeter) systems is discussed. Measurements made from the ground are favored over an airborne measurement as far as for the purpose of determining feasibility is concerned. The expected signal strengths for scattering at various altitude and elevation angles are examined; it appears that both molecular absorption and ambient turbulence degrade the signal at low elevation angles and effectively constrain the ground based measurement of elevation angles exceeding a critical value. The nature of the wind shear and turbulence to be expected are treated from a linear hydrodynamic model - a mountain lee wave model. The spatial and temporal correlation distances establish requirements on the range resolution, the maximum detectable range and the allowable integration time.
The results are reported of the research on the viscous interactions effects on transonic airfoil design and analysis. The boundary layer methods and the design program are discussed.
Results of the medically related activities of the NASA Application Team Program at the Research Triangle Institute are reported. A survey of more than 300 major medical device manufacturers has been initiated for the purpose of determining their interest and opinions in regard to participating in the NASA Technology Utilization Program. Design and construction has been commissioned of a permanent exhibit of NASA Biomedical Application Team accomplishments for the aerospace building of the North Carolina Museum of Life and Science at Durham, North Carolina. The team has also initiated an expansion of its activities into the Northeastern United States.
Results are presented of an initial experiment in a research program designed to develop objective techniques for psychological assessment of individuals and groups participating in long-duration space flights. Specifically examined is the rationale for utilizing measures of attention as an objective assessment technique. Subjects participating in the experiment performed various tasks (eg, playing matrix games which appeared on a display screen along with auditory stimuli). The psychophysiological reactions of the subjects were measured and are given. Previous research of various performance and psychophysiological methods of measuring attention is also discussed. The experiment design (independent and dependent variables) and apparatus (computers and display devices) are described and shown. Conclusions and recommendations are presented.
Two major marketing programs were initiated during 1974: (1) the unlimited search plan, and (2) the sales representative plan for northern California. The unlimited search plan was a six month program designed to offer clients multiple searches for a fixed fee. Although initial response was quite favorable, interest waned, and the plan was not renewed. Expansion and improvement of the on-line retrieval service continued. The ERIC thesaurus was added to the system. This thesaurus is an important acquisition as it gives the user greater flexibility in determining the best strategy for his search. Total terminal output time was reduced with a change to the direct access work file.
Dynamic modeling is being developed to provide a tool for systematic analysis of performance characteristics in energy systems where time-dependent behavior is important. A dynamic model program designed to aid in the understanding of solar collector behavior over the full range of operating conditions was constructed and tested in the evaluation of a conceptual collector design.
During Mars entry, each Viking Lander will collect and send to earth large quantities of measurement data, both scientific and engineering in nature. Software has been developed to statistically process this and other data in order to reconstruct, for mission support purposes, the entry trajectory, an 'engineering' atmosphere, and a wind profile. Procedures are described for processing limited amounts of the available data in such a manner that the maximum amount of information can be extracted therefrom, consistent with program design, response requirements, and mission operations constraints. Results of observability studies and simulations indicate that accuracy requirements will be met.
The paper discusses a program designed for the development of a GaAs IOC transmitter consisting of a monolithic surface laser whose output is coupled into patterned channel waveguides. Modulation and switching of the radiation occur in the waveguide circuit and are controlled separately. These structures are to be fabricated monolithically on a single semiconductor chip with each device amenable to integrated low-cost manufacture. The waveguide outputs of the IOC transmitter will be coupled to single mode optical fibers which form a transmission cable. The properties of the semiconductors (Ga,Al)As and (Ga,In)As permit performance of each of the basic functions included in the device considered. The concept of monolithic nondiscrete GaAs diode lasers is examined along with optical stripline channel waveguides and electro-optic channel waveguide modulators and switches.
Candidate autopilot control laws that control the engine failure transient sink rates by demonstrating the engineering application of modern state variable control theory were defined. The results of approximate modal analysis were compared to those derived from full state analyses provided from computer design solutions. The aircraft was described, and a state variable model of its longitudinal dynamic motion due to engine and control variations was defined. The classical fast and slow modes were assumed to be sufficiently different to define reduced order approximations of the aircraft motion amendable to hand analysis control definition methods. The original state equations of motion were also applied to a large scale state variable control design program, in particular OPTSYS. The resulting control laws were compared with respect to their relative responses, ease of application, and meeting the desired performance objectives.
The development of an experimental airborne multispectral scanner to provide both active (laser illuminated) and passive (solar illuminated) data from a commonly registered surface scene is discussed. The system was constructed according to specifications derived in an initial programs design study. The system was installed in an aircraft and test flown to produce illustrative active and passive multi-spectral imagery. However, data was not collected nor analyzed for any specific application.
An airfoil design program and a boundary layer analysis were developed. Boundary conditions were derived for ventilated transonic wind tunnels and performing transonic windtunnel wall calculations. A computational procedure for rotational transonic flow in engine inlet throats was formulated. Results and conclusions are summarized.
Auroral morphology is emphasized over auroral dynamics in a paper describing conspicuous auroral features picked up by the ISIS-2 scanning photometer. Results of improved programs designed to transform the data into a corrected geomagnetic coordinate frame and generate latitude profiles of auroral intensities at different magnetic local times are reported. The diffuse aurora and its relation to the morphology of discrete aurorae is given special attention.
Results of an IR survey program designed to obtain the spatial and brightness distributions of a representative sample of IR-emitting objects in the 3-30 micron range are analyzed. Small cryogenically cooled telescopes carried above the atmosphere on sounding rockets were employed in the research. Minimization of sky noise and photon background, experimental equipment, and data reduction techniques are discussed.
Report describes comprehensive test-and-evaluation program designed to improve performance of 7.5 kW electron-beam welder. Report describes prototype and seventeen changes incorporated to improve performance.