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Experiments have been carried out that suggest that the observed psychophysical impairment of motion detection in man may not occur equally over the entire visual field. Instead, if impaired motion detection is a consequence of redirection of 'attention' to another portion of the visual field, then movement detection may be impaired the most in the fovea and the least in the region of the subsequent target.
The possibility of accelerating particles with a focused laser is considered. The particle is accelerated transversely by the electric field and redirected to the forward direction within a single half-cycle by the magnetic field of the radiation. The equations of motion of the particle are solved and discussed. Special attention is given to an intuitive understanding of the constraint imposed by the geometry of the focal region. Optimum conditions are examined.
This study was undertaken to develop conceptual designs for a manned, space shuttle sortie mission laboratory capable of supporting a wide variety of experiments in conjunction with communications and navigation research. This space/laboratory would be one in which man may effectively increase experiment efficiency by certain observations, modifications, setup, calibration, and limited maintenance steps. In addition, man may monitor experiment progress and perform preliminary data evaluation to verify proper equipment functioning and may terminate or redirect experiments to obtain the most desirable end results. The flexibility and unique capabilities of man as an experimenter in such a laboratory will add greatly to the simplification of space experiments and this provides the basis for commonality in many of the supportive subsystems, thus reaping the benefits of reusability and reduced experiment costs. For Vol. 4, see N73-19268.
Acoustic measurements for large model eingine-over-the-wing (EOW) research configurations having both conventional and powered lift applications were taken for flap positions typical of takeoff and approach and at locations simulating flyover and sideline. The results indicate that the noise is shielded by the wing and redirected above it, making the EOW concept a prime contender for quiet aircraft. The large-scale noise data are in agreement with earlier small-model results. Below the wing, the EOW configuration is about 10 PNdb quieter than the engine-under-the-wing externally-blown-flap for powered lift, and up to 10 db quieter than the nozzle alone at high frequencies for conventional lift applications.
Development of a scientific rationale for an atmospheric probe designed to be capable of entry into either Saturn or Uranus. The effects of the NASA Monograph model atmospheres (SP 8091 and SP 8103) on the entry and descent trajectory specify instrument sampling design. The cool model atmospheres require descents to the vicinity of 20 bars to satisfy the objectives while about 4 bars is sufficient for the warm models. The measurement performance for a descent sampling time of 44 minutes shows that the atmosphere can be reconstructed from measured data. The required total probe entry weight is 103 kg, of which about 15 kg is for the science instruments. The descent data rate varies from 32 to 51 bps, depending upon the mode of transmitting preentry data. The resulting common probe can be redirected in flight between Saturn and Uranus.
Acoustic measurements for large model engine-over-the-wing (EOW) research configurations having both conventional and powered lift applications were taken for flap positions typical of takeoff and approach and at locations simulating flyover and sideline. The results indicate that the noise is shielded by the wing and redirected above it, making the EOW concept a prime contender for quiet aircraft. The large-scale noise data are in agreement with earlier small-model results. Below the wing, the EOW configuration is about 10 PNdB quieter than the engine-under-the-wing externally-blown-flap for powered lift, and up to 10 dB quieter than the nozzle alone at high frequencies for conventional lift applications.
A description of the scientific instrument arrangement for the large space telescope (LST) is given, with some of the rationale for selecting this concept. The first section of this report describes the basic configuration and was designed for an f/20 telescope focal plane. The subsequent LSTWG meeting held in November gave some redirection to the scientific requirements, and these changes are described in the section, Configuration Update.
The Phase B Extension of the Space Shuttle System Program Definition study was redirected to apply primary effort to consideration of space shuttle systems utilizing either recoverable pressure fed liquids or expendable solid rocket motor boosters. Two orbiter configurations were to be considered, one with a 15x60 foot payload bay with a 65,000 lb, due East, up-payload capability and the other with a 14x45 payload bay with 45,000 lb, of due East, up-payload. Both were to use three SSME engines with 472,000 lb of vacuum thrust each. Parallel and series burn ascent modes were to be considered for the launch configurations of primary interest. A recoverable pump-fed booster is included in the study in a series burn configuration with the 15x60 orbiter. To explore the potential of the swing engine orbiter configuration in the pad abort case, it is included in the study matrix in two launch configurations, a series burn pressure fed BRB and a parallel burn SRM. The resulting matrix of configuration options is shown. The principle objectives of this study are to evaluate the cost and technical differences between the liquid and solid propellant booster systems and to assess the development and operational cost savings available with a smaller orbiter.
An infrared wavelength variable attenuator based on contra-rotating germanium wedges is examined theoretically. The device redirects the paths of internal reflections associated with an optical flat to avoid closely spaced parallel beams at the output. Complementary wedges separated by an air gap compose an optical flat which, when combined with a masking arrangement, restricts unwanted reflections. A model of the device was built and experimentally evaluated. The results compare favorably with the dynamic range of attenuation of 2 to 50 db from theoretical calculations, and show a substantial reduction in the etalon effect associated with pairs of optical flats.
Efforts were directed toward surveying several supernova remnants for the emission of soft X-rays. Rather than attempt to detect such faint X-ray emission, the program was redirected to observe the spectrum and angular structure of the extended X-ray source in the Perseus cluster of galaxies and the super-nova remnant Puppis A. An attempt was made to detect X-ray line emission from Puppis A with a Bragg crystal spectrometer. Observations provide evidence for the presence of X-ray line emission in the spectrum of Puppis A near .65 keV.
Device prevents severe fuel sloshing and bubbling and redirects fluid motion to tank bottom. Cryogenic boiloff, wetted wall areas, and pressure collapse are reduced.
System consists of three major components: vertical deflector assembly, stationary reflector, and motor driven tracking mechanism. Deflector assembly directs incident incoming energy to a vertical direction, using series of horizontally mounted vanes. Energy is then redirected via reflector to fixed collector.
The MITRE methodological studies were conducted to define relevant questions in relation to the concept of total impact analysis and to provide a procedure for integrating diverse checklists of questions which trace the initial and secondary impacts of any major technological application or of society's attempts to respond to or redirect that application. Some of the results of that study are presented in tabular form.
Acoustic data obtained from a model-scale study with 5:1 slot nozzles are analyzed and correlated in terms of apparent noise sources. Variations in nozzle geometry include roof angle and sidewall cutback. In addition, geometry variations in wing size and flap deflection are included. Three dominant noise sources were evident in the data and correlated: fluctuating lift noise, trailing edge noise and a redirected jet mixing noise that included the effect of reflection of jet noise by the surface. Pertinent variables in the correlations include the shear layer thickness and peak jet flow velocity at the trailing edge.
Acoustic data obtained from a model-scale study with 5:1 slot nozzles are analyzed and correlated in terms of apparent noise sources. Variations in nozzle geometry include roof angle and sidewall cutback. In addition, geometry variations in wing size and flap deflection were included. Three dominant noise sources were evident in the data and correlated: fluctuating lift noise, trailing edge noise and a redirected jet mixing noise that included the effect of reflection of jet noise by the surface. Pertinent variables in the correlations included the shear layer thickness and peak jet flow velocity at the trailing edge.
A novel cover slide is reported which increases solar cell output by reducing the reflection of light from the cover slide surface and by redirecting incident light so that none falls on the collection grids of the cell. The new cover slide is fabricated with a sawtooth surface having a periodicity equal to that of the solar cell grids. This configuration refracts the light so that it is directed onto the semiconductor surface between the grid lines. Conventional grid patterns obstruct 7-10 percent of the light incident on the cell; at least half of this loss has been recovered by using the sawtooth cover slide. In addition, surface reflection from the conventional coated cover slide is suppressed by presenting a second surface to any light reflected at the first plane of contact. This double reflection results in a greater reduction of the reflection loss from the cover slide than does an antireflection coating on a flat surface.
Laser energy transmitted from a solar-power satellite via a set of relay satellites is used to power a cruising air transport; i.e., a laser-powered airplane. The result is a nearly fuelless pollution-free flight transportation system which is cost competitive with the fuel-conservative airplane of the future. The major components of this flight system include a laser-power satellite, relay satellites, laser-powered turbofans, and a conventional airframe. The relay satellites are orbiting optical systems which intercept the beam from a power satellite and refocus and redirect the beam to its next target.
In a solar cell array of terrestrial use, an improved double-sided solar cell package, consisting of a photovoltaic cell having a metallized P-contact strip and an N-contact grid, provided on opposite faces of the cell, a transparent tubular body forming an enclosure for the cell. A pedestal supporting the cell from within the enclosure comprising an electrical conductor connected with the P-contact strip provided for each face of the cell, and a reflector having an elongated reflective surface disposed in substantially opposed relation with one face of the cell for redirecting light were also included.