ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • GEOPHYSICS  (1,182)
  • AIRCRAFT  (324)
  • Cell & Developmental Biology
  • ENERGY PRODUCTION AND CONVERSION
  • 1980-1984
  • 1970-1974  (1,693)
  • 1945-1949
  • 1915-1919  (24)
  • 1972  (1,693)
  • 1916  (24)
Collection
Keywords
Publisher
Years
  • 1980-1984
  • 1970-1974  (1,693)
  • 1945-1949
  • 1915-1919  (24)
Year
  • 1
    facet.materialart.
    Unknown
    In:  Other Sources
    Publication Date: 2011-12-21
    Keywords: GEOPHYSICS
    Type: Life Sci. Publ., Vol. 2; 11 p
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Publication Date: 2005-11-30
    Description: Wind tunnel tests to determine the aerodynamic characteristics of basically similar short takeoff aircraft were conducted. The investigations were designed to provide data for a systematic direct comparison of five of the concepts considered. The configurations of the five models are illustrated and described. The aerodynamic data are presented in the form of graphs. It was concluded that the most complex systems require the least amount of net thrust.
    Keywords: AIRCRAFT
    Type: NASA. Langley Res. Center STOL Technol.; p 111-120
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Publication Date: 2005-11-30
    Description: Analysis, design, experimental static testing, wind-tunnel testing, and design integration studies are used to develop an augmentor wing jet flap configuration for a jet STOL transport aircraft having maximum propulsion and aerodynamic performance with minimum noise generation. The program has three basic elements: (1) static testing of a scale wing section to demonstrate augmentor performance and noise characteristics; (2) two-dimensional wind-tunnel testing to determine flight-speed effects on performance, and (3) system design and evaluation that optimizes the complete system and ensures that the design is compatible with the requirements for a large STOL transport having a 500-foot sideline noise of 95 perceived noise decibels (PNdb) or less.
    Keywords: AIRCRAFT
    Type: NASA. Lewis Res. Center Aircraft Engine Noise Reduction; p 291-304
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2005-11-30
    Description: A description of the performance test to compare noise output from a quiet engine with acoustic nacelle to the noise output of the JT3D turbofan engine is presented. Tabulations depict comparative thrusts, bypass ratios, core jet velocities, and fan jet velocities for both engines during simulated takeoff and approach performances.
    Keywords: AIRCRAFT
    Type: Aircraft Engine Noise Reduction; p 215-218
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Publication Date: 2005-11-30
    Description: The principal suppressor parameters and their relationships have been used to formulate a suppressor design methodology which has been applied to the design of several full-scale suppressors. Tests of these suppressors on several full-scale fans have demonstrated noise reductions of the order of 10 PNdB. The amount of suppression in several instances seems to have been limited by reaching noise floors that are not clearly at the estimated jet noise level but are not far above it. In addition to identifying noise floors, two other areas are considered. The first is attenuation by the fan exhaust suppressors, which seems in most cases to be less than that of the inlet. The second is the effectiveness of outer cowl treatment alone on multiple pure tones. This question relates to whether a high-speed fan can become as quiet as a low-speed fan without a substantial increase in the amount of treatment.
    Keywords: AIRCRAFT
    Type: Aircraft Engine Noise Reduction; p 63-102
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Publication Date: 2005-11-30
    Description: The important chemical reaction affecting the neutral composition of the upper stratosphere, mesosphere, and lower thermosphere is discussed. The role of atmospheric transport processes is emphasized and the problem of taking these into account is elucidated.
    Keywords: GEOPHYSICS
    Type: NASA, Washington Phys. of the Space Environment; p 147-155
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2005-11-30
    Description: The time-dependent response of the upper atmosphere to transient heat sources is considered. The basic problem is that of heating a compressible, heat-conducting fluid, which is described in the one-dimensional case by an analytic solution. Comparisons with satellite drag data of such first-order solutions are shown to be useful in determining energy requirements and in determining some constraints on the spatial distribution of the heating. Recent OGO-6 mass spectrometer and interferometric temperature measurements show that atmospheric disturbances during geomagnetic storms are much more prominent in the auroral zones. These results suggest that joule dissipation of auroral currents are important contributors to orbital perturbations of satellites.
    Keywords: GEOPHYSICS
    Type: NASA, Washington Phys. of the Space Environment; p 3-23
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2005-11-30
    Description: The heating and movement of the upper atmosphere at ionospheric levels in response to electric currents are discussed. Joule dissipation, generation of winds, and pressure gradients are significant factors in the energetics of the ionospheric electric currents flowing during magnetic storms and also of the Sq current system.
    Keywords: GEOPHYSICS
    Type: NASA, Washington Phys. of the Space Environment; p 25-40
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2005-11-30
    Description: Observing the development of upwelling on the northeast coast of Africa by measuring ocean surface emission with infrared radiometers on Nimbus satellites is reported. Using the temperature of the ocean as telemetered by the satellite, the biological potential of an area is estimated, and consequently the highest potential for fisheries.
    Keywords: GEOPHYSICS
    Type: Significant Accomplishments in Sci., 1970; p 14-17
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2005-11-30
    Description: The feasibility of carrying microwave radiometers on Nimbus E and F missions for sea ice surveys was studied in the arctic using aircraft. It was found that passive microwave signatures of Arctic Sea ice relate specifically to the structure and type of ice. It is concluded that a new tool for conducting ice surveys from aircraft and satellites with remote sensors was discovered.
    Keywords: GEOPHYSICS
    Type: Significant Accomplishments in Sci., 1970; p 18-21
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 11
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2005-11-30
    Description: The results of theoretical calculations for the reactions between electrons and negative hydrogen atoms are discussed for an electron colliding with a negative hydrogen ion and neutralizing the hydrogen ion by stripping the loosely bound electron from it, and the two free electrons moving away. A semi-quantum description of the process is presented in which the target is described in terms of quantum mechanics, and the projectile electron is described in a classical fashion.
    Keywords: GEOPHYSICS
    Type: Significant Accomplishments in Sci., 1970; p 58-62
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 12
    Publication Date: 2005-11-30
    Description: Externally-blown-flap noise research can be summarized by the following remarks: With lower-surface blowing, the sources of the flap noise are begining to be understood and the noise scaling laws have been established. Further, progress has been made on suppressing the flap interaction noise at the large flap deflections used during landing. Recent small-scale noise tests of configurations using external upper-surface blowing indicate that engine-over-the-wing configurations may be promising.
    Keywords: AIRCRAFT
    Type: Aircraft Engine Noise Reduction; p 259-290
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 13
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2005-11-30
    Description: STOL noise goals, noise sources, and their affects on engine and propulsion systems design are considered. It is shown that major noise sources constitute the blown-flap system with its turbofan engine and the augmentor wing propulsion system. Most of the problem areas associated with STOL propulsion systems are defined and the development of a multistage fan engine with proper rotor-stator spacings and low noise core exhaust jet is illustrated. A variable-area acoustic inlet provides near sonic flow conditions during takeoff and landing.
    Keywords: AIRCRAFT
    Type: Aircraft Engine Noise Reduction; p 247-258
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 14
    Publication Date: 2005-11-30
    Description: The acoustic and aerodynamic test results obtained with the two quiet engines are given in this presentation. Some of the test results reviewed include the performance of the untreated or baseline quiet engines. In addition, test results are shown for various degrees and areas of engine acoustic treatment. Finally, the results obtained on a flight-type, acoustically treated nacelle added to one of the quiet engines is examined.
    Keywords: AIRCRAFT
    Type: Aircraft Engine Noise Reduction; p 183-214
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 15
    Publication Date: 2005-11-30
    Description: Estimates of the prospects for quiet airplanes in the future are summarized. The SST using afterburning turbojets and no sound suppression is estimated to produce 129 EPNdb on the sideline. Suppression devices and operating techniques can reduce this noise markedly. The present fleet of 707's and DC-8's produces noises nearly as high as 120 decibels on approach. Combinations of sound absorbing devices and engine modifications are expected to give a noise near 100 decibels. The new advanced technology transports (ATT) are being studied with two noise goals in mind: one is 10 decibels and the other is 20 decibels below the FAR level of 106 on takeoff. New trijets using new quiet engines are expected to meet 90 EPNdb. Future advances in technology are expected to yield another 5 decibels to give noise levels of 80 EPNdb. The STOL airplane has a noise goal of 95 EPNdb along a sideline 500 feet from the runway.
    Keywords: AIRCRAFT
    Type: Aircraft Engine Noise Reduction; p 219-246
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 16
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2005-11-30
    Description: The static program has shown to date that very large noise reductions can be achieved by the sonic inlet concept with realistic inlet length and good aerodynamic performance. It is also shown that different inlet concepts produce substantially different results.
    Keywords: AIRCRAFT
    Type: NASA. Lewis Res. Center Aircraft Engine Noise Reduction; p 305-317
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 17
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2005-11-30
    Description: Three high performance fans were designed, built, and tested, accumulating 444 hours. All three fans are both aerodynamically and mechanically suitable for direct incorporation into engine applications. Two turbofan demonstrators to evaluate both low- and high-speed fan systems were also designed, built, and tested. All components and engine systems are demonstrating high reliability. These components have demonstrated advanced state-of-the-art in acoustics, aerodynamics, and mechanical design.
    Keywords: AIRCRAFT
    Type: NASA. Lewis Res. Center Aircraft Engine Noise Reduction; p 143-162
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 18
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2005-11-30
    Description: Estimates of noise reductions for high bypass ratio engines show that bypass ratio fan noise increases with increasing bypass ratio and dominates above a bypass ratio of about 1.0. Fan noise reduction to the level of jet noise is achieved by elimination of inlet guide vanes, elimination of second fan stage, and increased spacing between rotor and stator. Quiet engine design studies show that, at bypass ratios near 5 or 6 and with low noise fans, noise reductions in the order of 15 to 20 decibels relative to DC-8 and 707 airplanes engines are possible.
    Keywords: AIRCRAFT
    Type: Aircraft Engine Noise Reduction; p 139-142
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 19
    Publication Date: 2005-11-30
    Description: Tradeoffs between aerodynamic and acoustic properties of various fan configurations led to the selection of a variety of fans that produce noise levels in the range of 100 to 120 PNdb. Fan configuration and design pressure ratio required for specific mission operations depend in part on the type of mission to be performed. Noise data obtained for single-stage low speed fans, single-stage high speed fans, and two-stage fan engines are presented in table form.
    Keywords: AIRCRAFT
    Type: Aircraft Engine Noise Reduction; p 7-61
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 20
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2005-11-30
    Description: A discussion is presented on the bearing strength and bearing load-penetration relations in lunar soil. These were measured in air as a function of bulk density. It was found that the relation between bulk density and the logarithm of the bearing capacity is about linear. Shapes of the load vs penetration curves were observed to be similar to those obtained with particulate material of terrestrial origin.
    Keywords: GEOPHYSICS
    Type: NASA, Washington Analysis of Surveyor 3 Mater. and Phot. Returned by Apollo 12; p 227-232
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 21
    Publication Date: 2005-11-30
    Description: The discrepancy in temperature measurements of ionospheric electrons by Langmuir electrostatic probes, and radar backscatter are discussed. The discrepancy occurs at altitudes from 350 to 800km, and the probe temperatures are consistantly higher than the radar temperatures. It is concluded that the non-Maxwellian energy distribution provides an explanation for the altitude and the lower radar temperatures.
    Keywords: GEOPHYSICS
    Type: Significant Accomplishments in Sci., 1970; p 43-45
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 22
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2005-11-30
    Description: Passive microwave measurements were studied for determining sea state. It was found that the brightness temperature increases due to the foam produced by winds, and that the surface wind can be determined by the brightness temperature.
    Keywords: GEOPHYSICS
    Type: Significant Accomplishments in Sci., 1970; p 22-27
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 23
    Publication Date: 2005-11-30
    Description: Measurements of wave growth indicate an energy balance of the wave spectrum governed primarily by input from the atmosphere, nonlinear transfer to shorter and longer waves, and advection. The pronounced spectral peak and sharp low frequency cut-off characteristic of fetch-limited spectra are explained as a self-stabilizing feature of the nonlinear wave-wave interactions. The momentum transferred from the atmosphere to the wind waves accounts for a large part of the wind drag. These findings are relevant for remote microwave sensing of the sea surface by backscatter and passive radiometry methods.
    Keywords: GEOPHYSICS
    Type: NOAA Sea Surface Topography from Space, Vol. 2; 55 p
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 24
    Publication Date: 2005-11-30
    Description: Basic features of sea surface topography are reviewed, to show those oceanographic results which may be of value to a geodetic satellite program: (1) the shape and magnitude of the large scale features of the mean sea surface, relative to a level surface; (2) the position and magnitude of the slopes across the western boundary currents, from a variety of data; (3) an estimate of the position of the geoid, tied into the U.S. leveling network; and (4) a documented change of 60 to 70 cm in mean sea level, with respect to the geoid, between the U.S. east and west coasts.
    Keywords: GEOPHYSICS
    Type: NOAA Sea Surface Topography from Space, Vol. 2; 17 p
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 25
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2005-11-30
    Description: Reduction of fan noise emanating from turbofan engines by using acoustically treated nacelles is considered. Test performance prediction for an acoustically lined nacelle having a three ring inlet, a single ring fan duct, and external cowling expect a 15 PNdb fan noise reduction with 5 percent takeoff thrust loss and a 5.4 percent cruise specific fuel consumption increase.
    Keywords: AIRCRAFT
    Type: NASA. Lewis Res. Center Aircraft Engine Noise Reduction; p 163-181
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 26
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2005-11-30
    Description: Progress reported on principle NASA programs for the reduction of aircraft engine noise emphasizes the Quiet Engine Program. Considered are fan noise and performance, fan noise suppression, and jet noise reduction for a broad spectrum of airplanes including new subsonic airplanes, the older subsonic airplanes in service today, STOL airplanes of the future, and future supersonic transports. Noise reductions achieved in the framework of the Quiet Engine Program are demonstrated and future possible applications of low noise technology to airplanes are discussed.
    Keywords: AIRCRAFT
    Type: Aircraft Engine Noise Reduction; p 1-5
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 27
    Publication Date: 2005-11-30
    Description: The vibration environment in a wide range of aerospace and surface vehicles is examined, and definitions related to ride evaluation are reviewed. Three provinces of research and application of ride data are recognized: (1) ride affecting passenger and operator comfort; (2) ride affecting human efficiency; and (3) ride affecting the health and safety of occupants occupationally or repeatedly exposed. Specific reference is made to the proposed ISO guide on human exposure to whole-body vibration. The applications as well as the advantages and limitations of this guide for evaluating vehicle ride are discussed. The derivation of the limits is reviewed with regard to the supporting data and the compromises necessary for wide applicability. Special discussions are included of the frequency and time dependence of these limits and approaches in progress for adjusting them according to different criteria of application.
    Keywords: AIRCRAFT
    Type: NASA. Langley Res. Center Symp. on Vehicle Ride Quality; p 175-196
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 28
    Publication Date: 2005-11-30
    Description: Satellite observations of electron temperature and the topside electron density structure are used to calculate the red arc according to the thermal conduction model. In this model, energy from the magnetosphere flows in the electron gas along geomagnetic field lines into the ionosphere. This energy heats the ambient F-region electrons sufficiently to excite the oxygen atoms to the O I(1D) level by collisional impact giving rise to the 6300 A emission characteristic of the arc. For the 31 October/1 November 1968 red arc, the calculated emission rate, geographical position, and horizontal extent of the red arc are in agreement with the photometric data obtained by airglow observatories. Almost all of the energy conducted into the red arc is ultimately transferred to the neutral gas through elastic and inelastic collisions. This energy drives a large thermal cell and the circulation extends the influence of the arc thousands of kilometers beyond the region of direct heat input. The calculated neutral gas temperature response to electron heating within the arc is small.
    Keywords: GEOPHYSICS
    Type: NASA, Washington Phys. of the Space Environment; p 45-69
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 29
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2005-11-30
    Description: Miniature mass spectrometers were developed and were carried on sounding rockets to determine the composition of the upper atmosphere. Techniques have been developed that accurately correct for the velocity and spin of the moving vehicle. Above 120 km N2, O2, and Ar appear to be in diffusive equilibrium. Most He concentration measurements show a more rapid decline with altitude than predicted by diffusive equilibrium. Because of the highly reactive nature of atomic oxygen, measurements of this species by mass spectrometry are low by an unknown factor.
    Keywords: GEOPHYSICS
    Type: NASA, Washington Phys. of the Space Environment; p 129-145
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 30
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2005-11-30
    Description: The seasonal changes in aspect of the Niger River in the Republic of Mali, West Africa, as seen in daytime imagery obtained by the high-resolution infrared radiometer on Nimbus 3 are described. The identification of different plants by their reflectance is shown to provide an ecological map that changes with time. It is concluded that Nimbus imagery provides an integrated view of the entire watershed on a daily basis.
    Keywords: GEOPHYSICS
    Type: Significant Accomplishments in Sci., 1970; p 8-13
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 31
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2005-11-30
    Description: Daily Tiros and ESSA satellite television nephanalysis over the Pacific Ocean were collected, and monthly cloud charts drawn to study the interaction of tropical oceans with the atmosphere. The data were correlated with climatological data for rainfall and surface temperatures.
    Keywords: GEOPHYSICS
    Type: Significant Accomplishments in Sci., 1970; p 28-31
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 32
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2005-11-30
    Description: Local geology of Hadley Rille near the landing site of Apollo 15 is described. Orbital photography from the Hasselblad, metric, and panoramic cameras is used to study regional relationships of the rille. The shape of the rille due to various natural causes is examined, along with stratigraphic measurements of mare materials.
    Keywords: GEOPHYSICS
    Type: NASA. Manned Spacecraft Center Apollo 15 Prelim. Sci. Rept.; 5 p
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 33
    Publication Date: 2005-11-30
    Description: High resolution panoramic photographs taken from 110 km orbits of the command service module show the lunar module structure on the moon as evidenced by reflected light and by the shadow. Before and after photographs of the landing site are presented; the increased brightness or halo is attributed to mare surface materials.
    Keywords: GEOPHYSICS
    Type: NASA. Manned Spacecraft Center Apollo 15 Prelim. Sci. Rept.; 3 p
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 34
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2005-11-30
    Description: Although tides and tsunamis are both shallow water waves, it does not follow that they are equally amenable to an observational program using an orbiting altimeter on a satellite. A numerical feasibility investigation using a hypothetical satellite orbit, real tide observations, and sequentially increased levels of white noise has been conducted to study the degradation of the tidal harmonic constants caused by adding noise to the tide data. Tsunami waves, possibly a foot high and one hundred miles long, must be measured in individual orbits, thus requiring high relative resolution.
    Keywords: GEOPHYSICS
    Type: Sea Surface Topography from Space, Vol. 2; 30 p
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 35
    Publication Date: 2005-11-30
    Description: The main conclusions reached are: (1) At low subsonic jet exhaust velocities, jet noise varies as the velocity to the eighth power; (2) at high subsonic exhaust velocities, jet noise approaches a variation with velocity to the third power; (3) use of the jet density squared overcorrects density effects on jet noise; (4) subsonic and supersonic jet noise levels can be predicted; and (6) use of multielement nozzles and acoustically lined ejectors significantly suppress jet noise at intermediate jet exhaust velocities.
    Keywords: AIRCRAFT
    Type: Aircraft Engine Noise Reduction; p 103-137
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 36
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2005-11-30
    Description: Rather than a pattern of cracks in an apparently flat surface, the Apollo 12 photographs suggest an irregular surface that consists of clods or fragments. The impression of flat tiles and crusting, obtained by monoscopic viewing, is an illusion. Instead, the lunar soil deforms and cracks in the same manner as homogeneous isotropic terrestrial soils of moderate bulk density, having a small amount of cohesion.
    Keywords: GEOPHYSICS
    Type: NASA, Washington Analysis of Surveyor 3 Mater. and Phot. Returned by Apollo 12; p 233-235
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 37
    Publication Date: 2005-11-30
    Description: The Proclus Crater region was mapped to test the value, for photogeologic mapping purposes, of Apollo 15 metric photographs and to estimate the scientific value of the area as a potential landing site. Adjacent frames of the metric photography were overlapped with the base frame to provide stereographic images. Because of the high quality of the photographs, it was found that the geologic units could be more definitely interpreted and dated than those of earlier maps. The photographs tend to confirm the earlier interpretation of the rugged area as composed of bedrock uplifted when the Crisium basin formed. They also suggest that an earlier predominantly volcanic interpretation of the terra in this area might be replaced by an interpretation in which mass wasting and fracturing play the major roles in producing different terrain types. It was concluded that because of apparent lithologic homogeneity, the terra of the Proclus region is an undesirable objective for an extensive manned lunar landing mission.
    Keywords: GEOPHYSICS
    Type: NASA. Manned Spacecraft Center Apollo 15 Prelim. Sci. Rept.; 4 p
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 38
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2005-11-30
    Description: The location of the outer boundary of the geomagnetic field, or magnetopause, and the location of the earth's bow shock have been compiled based on data from the first six IMP satellites.
    Keywords: GEOPHYSICS
    Type: Significant Accomplishments in Sci., 1970; p 81-85
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 39
    Publication Date: 2006-03-12
    Description: Some of the elementary methods used in deriving true-height profiles from oblique-incidence ionograms are reviewed. The two principal methods presented are oblique-to-vertical transformation and direct inversion of the oblique-incidence ionogram. Limitations in oblique-incidence inversion due to magnetic-field effects, horizontal gradients, and absolute time delay are discussed.
    Keywords: GEOPHYSICS
    Type: NASA. Ames Res. Center Math. of Profile Inversion; 12 p
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 40
    Publication Date: 2006-03-12
    Description: A method is described to accomplish automatic data selection and profile inversion to obtain ionospheric electron density profiles from digitized radio soundings. The profile inversion is based on a well-established formulation by which the optimum radio frequency sounding intervals can be specified from an approximate knowledge of the profile; the expected virtual height coordinates (h) at these frequencies (f) are estimated, and procedures are then used to select h(f) observations nearest the predicted coordinates from a subsequent digital ionogram. From these the next profile is obtained. The process adaptively follows the changing shape and detail of the profile. The procedure requires an average of 15 sec per profile on a standard data processing computer, and can be adapted, with benefit to online real-time use in a digital ionosonde.
    Keywords: GEOPHYSICS
    Type: NASA. Ames Res. Center Math. of Profile Inversion; 11 p
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 41
    Publication Date: 2006-03-12
    Description: A general review is given of the inversion techniques used to derive the ionospheric electron density N as a function of altitude h from group path P versus frequency f measurements obtained by vertical incidence ionospheric sounders. The paper discusses the medium under investigation, the experimental techniques used to obtain the P(f) data, the theoretical considerations leading to the integral equation relating P(f) to N(h), and the assumptions made in the inversion process. The lamination inversion technique is then presented, with special attention given to mathematical difficulties arising from discontinuities in the P(f) function, infinities in the integrand, and in some cases unknown integration limits. Methods outlined for minimizing the uncertainties due to discontinuities include the use of redundant information - that is the two distinct P(f) functions available for a given N(h) profile - and the use of models based on statistical data. Mathematical procedures are discussed that increase significantly the efficiency and accuracy of the required numerical integrations. The accuracy of the inversion technique is deduced by comparing the resulting N(h) profile with N(h) data obtained by simultaneous but independent observations.
    Keywords: GEOPHYSICS
    Type: Math. of Profile Inversion; 13 p
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 42
    Publication Date: 2006-03-12
    Description: Statistical retrieval methods for remote sounding are reviewed. Methods are given for constraining an essentially incomplete problem by means of the known statistical behavior of the solution. Information content of the observations and the meteorological structure are discussed. Linear versions of maximum probability and minimum variance methods are given in some detail, and extensions to the nonlinear case are described.
    Keywords: GEOPHYSICS
    Type: NASA. Ames Res. Center Math. of Profile Inversion; 10 p
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 43
    Publication Date: 2006-03-12
    Description: The mathematical inversion of light-scattering observations to obtain the atmospheric ozone profile is discussed in terms of the filtering properties of the physical and mathematical processes for different spatial scales. Within this context, it is shown that the physical process of scattering acts as a low pass filter; which transfers large-scale profile information efficiently to radiance observations but very strongly attenuates small- or fine-scale profile information. To avoid domination of the mathematical inversion by the random error of radiance measurements, an equivalent spatial-scale filtering in the inversion procedure is essential. The available evidence suggests that mathematical inversion to obtain the low level ozone profile below 25 to 30 km is either inferior to or no better than the statistical estimation of the profile using total ozone as predictor. However, inversion profiles for high level ozone above 25 to 30 km appear to have moderately good accuracy.
    Keywords: GEOPHYSICS
    Type: NASA. Ames Res. Center Math. of Profile Inversion; 24 p
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 44
    Publication Date: 2006-03-12
    Description: Mathematical techniques used in atmospheric profile inversion are reviewed, with the discussion limited to methods that do not require extensive information on the statistical properties of the profiles. The basic problem of the calculation of vertical profiles from noise contaminated infrared spectral measurements is examined. Three specific examples of methods of solution are given: the iterative minimum estimation method, a second linear iterative method, and the algorithm of Chahine. Satellite data are used in an empirical comparison of the methods. Several factors are considered, including the stability of solutions, convergence behavior of the iterative methods, and dependence of the solutions on the first guess, a factor that is particularly important in the treatment of data from other planets.
    Keywords: GEOPHYSICS
    Type: Math. of Profile Inversion; 14 p
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 45
    Publication Date: 2006-04-26
    Description: A flight test experiment is described, in which various aspects of ride qualities were explored. Situations included simulated cruise and terminal area maneuvers, as might be typical of STOL transport operations. Various motion components were studied in isolation and in many combinations. The experiment included runs with and without turbulence, variations in airplane stability and handling qualities, and differences of pilot technique. The ride quality was strongly affected by roll, yaw, and heave motions; but very little by pitching. It was strongly affected by airplane stability and handling qualities and, in some cases, by piloting technique.
    Keywords: AIRCRAFT
    Type: NASA. Langley Res. Center Symp. on Vehicle Ride Quality; p 67-89
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 46
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2006-04-26
    Description: An analysis of the factors which affect riding comfort in various modes of transportation is presented. The subjects discussed are: (1) human factor elements in ride quality, (2) current knowledge of flight dynamics and relation to passenger acceptance, (3) study requirements for human factors in ride quality, and (4) possible criteria for human factor in ride quality.
    Keywords: AIRCRAFT
    Type: Symp. on Vehicle Ride Quality; p 1-22
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 47
    Publication Date: 2006-04-26
    Description: Equipment for studying the amplitude frequency response of the ionospheric scattering channel is described, having multipath signal propagation. Experimental results are reported, including nonuniformity in the channel's amplitude frequency response.
    Keywords: GEOPHYSICS
    Type: Morphology of the Quiet and Disturbed Ionosphere; p 39-45
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 48
    Publication Date: 2006-04-26
    Description: The results of the parameters of small-scale ionization inhomogeneities study of the ionosphere's F-region for October-November 1965 and January-February 1966 are presented. It is shown that the most probable values of the inhomogeneity parameters are as follows: degree of anisotropy 1.4-2; vertical dimension 200-400 m; horizontal dimensions along major and minor axes 400-1000 and 200-600 m, respectively; rate of chaotic motions 30-60 m/sec; lifetime 6-9 sec.
    Keywords: GEOPHYSICS
    Type: Morphology of the Quiet and Disturbed Ionosphere; p 23-29
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 49
    Publication Date: 2006-04-26
    Description: Smearing of the scattered-energy flux density over a range of angles of arrival permits the use of a receiving-end antenna with a height lower than theoretical.
    Keywords: GEOPHYSICS
    Type: Morphology of the Quiet and Disturbed Ionosphere; p 65-68
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 50
    Publication Date: 2006-04-26
    Description: The eclipse effect was manifested during the second phase: the ionization of the F1- and F2-layers decreased and the minimum effective heights of E and F2 increased due to recombination processes. The manner in which electron density is distributed over the levels was ascertained from analysis of N(t) curves.
    Keywords: GEOPHYSICS
    Type: Morphology of the Quiet and Disturbed Ionosphere; p 35-38
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 51
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2006-04-26
    Description: Diurnal and seasonal absorption curves measured by a radio astronomical method at Alma-Ata during the IQSY (1964-1965) are submitted. The apparatus is described. The dependence of absorption on solar flares is also indicated.
    Keywords: GEOPHYSICS
    Type: Morphology of the Quiet and Disturbed Ionosphere; p 30-34
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 52
    Publication Date: 2006-04-26
    Description: The basic patterns are described in the behavior of critical frequencies and minimum effective heights of the ionosphere's reflecting E, F1, and F2 layers, according to ionospheric recorder measurements from 1943 to 1967. The variations of critical frequencies and virtual heights are compared with the relative sunspot numbers and the flux of the sun's radio emission at 10.7 cm.
    Keywords: GEOPHYSICS
    Type: Morphology of the Quiet and Disturbed Ionosphere; p 1-6
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 53
    Publication Date: 2006-04-26
    Description: The problem of selecting a vertical base in the ionosphere that permits registration of vertical motions of small-scale ionization inhomogeneities of the ionosphere's F-region is discussed. The accuracy of calculation of the vertical drift-velocity component is estimated.
    Keywords: GEOPHYSICS
    Type: Morphology of the Quiet and Disturbed Ionosphere; p 7-12
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 54
    Publication Date: 2006-04-26
    Description: A test program was undertaken to determine airline passenger reaction to vibration environments that might be encountered in a supersonic transport or other large commercial jet aircraft. The principal problem addressed was to determine accelerations of vertical and lateral vibration that people find objectionable. Further questions experimentally posed were: (1) what is the relationship between human reactions to vertical and lateral vibration, (2) to single- and combined-frequency vibration, and (3) to single- and combined-axis vibration? Interest was confined to reactions to vibration in the frequency range of 0.20 to 7.0 Hz, a range typical of the vibration environment of a large airplane. Results indicated an increasing sensitivity to vertical vibration as frequency was increased from 1.0 to 7.0 Hz. Subjects were found most sensitive to lateral vibration in the 1.0 to 3.0 Hz range. There was a nearly linear decrease in sensitivity as frequency of lateral vibration was increased from 3.0 to 7.0 Hz.
    Keywords: AIRCRAFT
    Type: NASA. Langley Res. Center Symp. on Vehicle Ride Quality; p 91-113
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 55
    Publication Date: 2006-04-26
    Description: A flight test program to determine the effects of low frequency vibrations on passengers in short haul aircraft is discussed. The objective of the program is to accumulate flight test data on aircraft ride quality in terms of vehicle motion and acceleration and human responses. The subjects discussed are: (1) test procedures, (2) data processing, and (3) the program schedule.
    Keywords: AIRCRAFT
    Type: Symp. on Vehicle Ride Quality; p 247-251
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 56
    Publication Date: 2006-04-26
    Description: The approach of an aircraft manufacturer to ride quality in air transportation is presented. The subjects discussed are: (1) the external and internal environment in terms of vibration and acoustic sources and general response, (2) guidelines and criteria reflecting current practice, (3) present and future efforts to develop rideability criteria, and (4) requirements for data, criteria, and research in various rideability areas.
    Keywords: AIRCRAFT
    Type: NASA. Langley Res. Center Symp. on Vehicle Ride Quality; p 23-49
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 57
    Publication Date: 2006-04-26
    Description: A method is proposed for measuring the phase difference fluctuations between vibrations at different frequencies that result from scattering properties of the medium. The measurement equipment is described, along with an ideal communication channel.
    Keywords: GEOPHYSICS
    Type: Morphology of the Quiet and Disturbed Ionosphere; p 47-54
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 58
    Publication Date: 2006-04-26
    Description: The results of measurements of field strength and signal/noise ratio on experimental ionospheric-scattering short wave radio links are presented. It is shown that the seasonal and diurnal variations of field strength are determined by features of solar and meteoric activity. The role of the sporadic E-layer in propagation of short radio waves at frequencies exceeding MUF-F2 is noted.
    Keywords: GEOPHYSICS
    Type: Morphology of the Quiet and Disturbed Ionosphere; p 55-59
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 59
    Publication Date: 2006-04-26
    Description: The state of the ionosphere above stations in Kazakhstan is examined in connection with the proton flares of 7 July, 28 August, and 2 September 1966. Universal time is used. It is established that a proton flare causes increased radio absorption (the ionization of the D-region is enhanced, and the minimum reflected frequencies decrease). Magnetic storms and ionospheric disturbances are observed on the earth one-and-a-half to two days after some proton flares.
    Keywords: GEOPHYSICS
    Type: Morphology of the Quiet and Disturbed Ionosphere; p 17-22
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 60
    Publication Date: 2006-04-26
    Description: The diurnal variations of the critical frequencies of the ionospheric F2 region may be influenced substantially by the 12-hour component of the vertical drift of small-scale ionization inhomogeneities. The appearance of the forenoon maximum of F2 and the evening ionization maximum are examined.
    Keywords: GEOPHYSICS
    Type: Morphology of the Quiet and Disturbed Ionosphere; p 13-16
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 61
    Publication Date: 2006-04-26
    Description: The electric fields at the solar activity minimum on the magnetic equator are evaluated based on data from rocket studies of the vertical profiles of the ionospheric-current magnetic fields and electron concentration. The electric field strength is 1-4 X 100 CGSM units. In addition, the electric field has altitude and time distributions. Its maximum is observed at a height of 110 km, and at 90 and 140 km, it is smaller by a factor of 3-4 than at the 110-km height. The maximum values are registered around noon.
    Keywords: GEOPHYSICS
    Type: Morphology of the Quiet and Disturbed Ionosphere; p 82-89
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 62
    Publication Date: 2006-04-26
    Description: Curves of H (the horizontal component) and Z (the vertical component) of the magnetic field from a strip with an assigned current-density distribution compiled from the results of electrical modelling are calculated. The calculated curves are compared qualitatively with latitude curves obtained from ground magnetic observatory data. It is shown that the forms of the theoretical H and Z and the experimental latitude variations are qualitatively similar.
    Keywords: GEOPHYSICS
    Type: Morphology of the Quiet and Disturbed Ionosphere; p 90-94
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 63
    Publication Date: 2006-04-26
    Description: Measurement results are presented for actual utilization of the short wave frequency band, obtained by continuous registration of the number of radio stations in the 16-23 MHz band over an annual cycle (1965). It is shown that there is a relation between the number of radio stations and the variations of MUF-F2. During years of minimum solar activity and at night, segments free of radio stations operating by normal reflection, can be selected in the 18-23-MHz band for ionospheric-scattering links.
    Keywords: GEOPHYSICS
    Type: Morphology of the Quiet and Disturbed Ionosphere; p 60-64
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 64
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2006-03-12
    Description: Acoustic radar sounding techniques were used to measure the wind velocity and direction in the first 300 m of the atmosphere. Angle-of-arrival and Doppler techniques were developed to obtain two independent measurements of the wind field. These techniques and preliminary experimental results are described briefly.
    Keywords: GEOPHYSICS
    Type: NASA. Ames Res. Center Math. of Profile Inversion; 11 p
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 65
    Publication Date: 2006-03-12
    Description: Vertical temperature profiles are derived from radiation measurements by inverting the integral equation of radiative transfer. Because of the nonuniqueness of the solution, the particular temperature profile obtained depends on the numerical inversion technique used and the type of auxiliary information incorporated in the solution. The choice of an inversion algorithm depends on many factors; including the speed and size of computer, the availability of representative statistics, and the accuracy of initial data. Results are presented for a numerical study comparing two contrasting inversion methods: the statistical-matrix inversion method and the nonstatistical-iterative method. These were found to be the most applicable to the problem of determining atmospheric temperature profiles. Tradeoffs between the two methods are discussed.
    Keywords: GEOPHYSICS
    Type: NASA. Ames Res. Center Math. of Profile Inversion; 7 p
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 66
    Publication Date: 2006-03-27
    Description: A program plan to develop criteria for airworthiness standards for STOL transport aircraft is presented. Initially, three different STOL concepts are to be examined with a goal to arrive at a generalized set of standards. The Breguet 941 deflected-slipstream STOL has been initially evaluated on a piloted motion simulator and in flight. Confidence in establishing criteria for airworthiness standards for STOL transport aircraft has been obtained from these studies.
    Keywords: AIRCRAFT
    Type: STOL Technol.; p 345-351
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 67
    Publication Date: 2006-03-27
    Description: The Augmentor-Wing Jet STOL Research Aircraft has been developed and has started flight tests. The objectives of the program are to compare aerodynamic characteristics predicted from wind-tunnel data with data obtained in flight, to determine flight dynamic characteristics and limitations of the augmentor-wing concepts, and to contribute to the development of STOL design and operational criteria. Initial flight test results have shown that the aerodynamic characteristics are close to values predicted from wind-tunnel tests. The lateral-directional stability and control characteristics are satisfactory for research STOL missions with stability augmentation, but the longitudinal control require improvement. STOL take-off distance over 11 m is about 290 m, and landing approach speeds are between 60 and 65 knots. The investigation of the STOL operational and performance characteristics is continuing.
    Keywords: AIRCRAFT
    Type: STOL Technol.; p 259-282
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 68
    Publication Date: 2006-03-27
    Description: The considerations involved in making a piloted simulator an effective research tool in the design and development of new aircraft are discussed. An assessment of the limitations of the simulator in depicting real flight as well as the problem of recognizing erroneous results when the simulator is supplied with incorrect input data is made. Examples of the ways in which the simulator is used to design and develop the augmentor-wing aircraft are presented. Four areas of investigation are: (1) to design the lateral control system for proper feel and response, (2) determine the effect of engine failure during approach, (3) develop the best technique for controlling flight path during approach, and (4) the significance of lift loss in ground effect and how to compensate for such loss.
    Keywords: AIRCRAFT
    Type: Stol Technol.; p 283-290
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 69
    Publication Date: 2006-03-27
    Description: A STOL ride-control development program has been initiated with the objective of generating ride-control technology through development and evaluation of an active control system specifically designed to provide ride smoothing on a STOL vehicle. Although much can be learned through analysis, there are deficiencies in technology for translating analysis results into operating hardware. The general approach being followed is to select an existing STOL vehicle for trial and then carry out a study to establish feasibility of a control system or systems to smooth the ride and generate system trade-off data.
    Keywords: AIRCRAFT
    Type: STOL Technol.; p 215-226
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 70
    Publication Date: 2006-03-27
    Description: The development of STOL technology for application to operational short-haul aircraft is accompanied by the requirement for solving problems in many areas. One of the most obvious problems is STOL aircraft operations in the terminal area. The increased number of terminal operations needed for an economically viable STOL system as compared with the current CTOL system and the incompatibility of STOL and CTOL aircraft speeds are positive indicators of an imminent problem. The high cost of aircraft operations, noise pollution, and poor short-haul service are areas that need improvement. A potential solution to some of the operational problems lies in the capability of making curved landing approaches under both visual and instrument flight conditions.
    Keywords: AIRCRAFT
    Type: STOL Technol.; p 245-258
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 71
    Publication Date: 2006-03-27
    Description: Analytical investigations and piloted moving base simulator evaluations were conducted for manual control of flight path and airspeed for the approach and landing of a powered lift jet STOL aircraft. Flight-path and airspeed response characteristics were described analytically and were evaluated for the simulation experiments which were carried out on a large motion simulator. The response characteristics were selected and evaluated for a specified path and speed control technique. These characteristics were the initial flight-path response, flight-path overshoot, flight-path-airspeed coupling in response to a change in thrust, and the sensitivity of airspeed to pitch-attitude changes. Results are presented in the form of pilot opinion ratings and commentary, substantiated where appropriate by response time histories and aircraft states at the point of touchdown.
    Keywords: AIRCRAFT
    Type: STOL Technol.; p 181-198
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 72
    Publication Date: 2006-03-27
    Description: Data from wind-tunnel measurements are presented to show the magnitude of adverse ground effects on the longitudinal aerodynamic coefficients of a powered-lift STOL airplane. A steady-state analysis shows the changes in thrust and angle of attack required during the landing approach and flare as the airplane flies close to the ground. The piloting problems that these ground effects may create were investigated with an in-flight simulator to find the consequences of lift loss during the landing-flare maneuver for a STOL transport. Flight tests were made using the variable stability Navion setup with STOL transport aerodynamics and control responses and were flown at design approach speeds and descent conditions.
    Keywords: AIRCRAFT
    Type: STOL Technol.; p 199-213
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 73
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2006-03-27
    Description: Short takeoff aircraft technology development related to the requirements for an expanded and improved short-haul air transportation system is discussed. Systems requirements are summarized, principal aircraft requirements are identified, the status of STOL technology is analyzed, and the scope of the technology efforts covered by the conference are outlined. Charts and diagrams are provided to explain system requirements, lift capability trends, and terminal airspace requirements.
    Keywords: AIRCRAFT
    Type: STOL Technol.; p 35-42
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 74
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2006-03-27
    Description: The application of short takeoff and landing aircraft for improving short-haul air transportation is examined. The contracts with industry to study quiet turbofan short-field aircraft in the short-haul air transportation system are identified. Studies of appropriate propulsion systems are conducted in parallel with the aircraft studies. The objectives of the studies are to: (1) determine economic and social viability of short-haul air transportation, (2) identify critical technology and technology-related problems, (3) define representative aircraft configurations and characteristics to include development and operational costs, and (4) to establish desirable technology advances for improving short-haul transportation systems.
    Keywords: AIRCRAFT
    Type: STOL Technol.; p 9-22
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 75
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2006-03-27
    Description: The requirements for short-haul air transportation services in the 1980 time period are analyzed. The identification of short takeoff and landing aircraft to perform this service is reviewed. The adequacy of technical programs for developing short-haul aircraft is examined. The characteristics of several candidate short-haul aircraft are described. A system analysis, to include the economic and environmental factors, is developed.
    Keywords: AIRCRAFT
    Type: STOL Technol.; p 1-8
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 76
    Publication Date: 2006-03-12
    Description: The direct problem is to compute reflection coefficients for an assumed electron-density profile, using a full-wave solution. The inverse problem is treated numerically, using derivatives of the reflection matrix with respect to model parameters. A technique for the rapid computation of the derivatives is described. An algorithm for determining resolution in the profile is discussed.
    Keywords: GEOPHYSICS
    Type: NASA. Ames Res. Center Math. of Profile Inversion; 7 p
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 77
    Publication Date: 2006-03-12
    Description: A method for converting topside sounder ionograms into topside electron density profiles is discussed. The lamination method used is modified to take into account the variation of electron density and magnetic field within each lamination. Also included is a change of variable to produce a finite integrand of the integral involved, an iteration scheme that permits convergence on an initially unknown density, a second iteration scheme to overcome the problem of an uncertainty in the electron density at the satellite, and a modification to compensate for the changing satellite altitude over the duration of the sounding. Two applications of the technique are discussed: field-aligned traces for computing field-aligned profiles and computer-aided systems for scaling ionograms.
    Keywords: GEOPHYSICS
    Type: NASA. Ames Res. Center Math. of Profile Inversion; 11 p
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 78
    Publication Date: 2006-03-12
    Description: An operational two-satellite microwave occultation system will establish a pressure reference level to be used in fixing the temperature-pressure profile generated by the SIRS infrared sensor as a function of altitude. In the final error analysis, simulated data for the SIRS sensor were used to test the performance of the occultation system. The results of this analysis indicate that the occultation system is capable of measuring the altitude of the 300-mb level to within 24 mrms, given a maximum error of 2 K in the input temperature profile. The effects of water vapor can be corrected by suitable climatological profiles, and improvements in the accuracy of the SIRS instrument should yield additional improvements in the performance of the occultation system.
    Keywords: GEOPHYSICS
    Type: NASA. Ames Res. Center Math. of Profile Inversion; 13 p
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 79
    Publication Date: 2006-03-12
    Description: A ground-based vertically pointing FM-CW radar is described that permits remote probing of the refractive index structure in the troposphere. The radar has the characteristics of extremely high sensitivity, ultrahigh range resolution, and close minimum detection range without clutter. The sounder routinely detects layer structures in the lower troposphere. These layers are always associated with gradients in the vertical refractive index profile, and are frequently very thin, approaching the resolution of the radar (1 m). Very often they are perturbed by wave motions. Examples of various wave patterns are presented, and an explanation is given for organized substructures frequently superimposed on larger scale wave motions.
    Keywords: GEOPHYSICS
    Type: NASA. Ames Res. Center Math. of Profile Inversion; 8 p
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 80
    Publication Date: 2006-03-12
    Description: The requirements for a numerical inversion method to calculate electron density profiles from ionograms are discussed. A systematic investigation about the independence of the two magnetoionic components shows that the extent to which the range of ambiguity can be reduced depends mainly on the magnetic latitude. Error estimates and first-order corrections for less elaborate methods are included.
    Keywords: GEOPHYSICS
    Type: NASA. Ames Res. Center Math. of Profile Inversion; 13 p
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 81
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2006-03-12
    Description: Several alternative methods for solving the group height equation are presented. Three of these are now in operation at Ames Research Center and use data contained in a single ionogram trace. From the data an electron density profile N(h) is computed. If the ionogram also exhibits other traces, reverse ionogram traces are computed, using the N(h) profile, for comparison with the redundant data. When agreement is poor, the initial data trace is reinterpreted, another N(h) profile computed, and the reverse traces generated once again. This process is repeated until a desired degree of consistency is achieved. To reduce the necessity for human intervention and eliminate decision making required in conjunction with the preceding methods, a method is proposed that accepts as input, all data from a single ionogram. In general, no electron density function will satisfy these data exactly, but a best N(h) profile can be computed. Finally, a method is described that eliminates the need to assume that the ionosphere is spherically stratified. Horizontal gradients in electron density are detected and accounted for by processing several ionograms from the same satellite pass simultaneously. This idea is derived as an extension of one of the basic methods.
    Keywords: GEOPHYSICS
    Type: NASA. Ames Res. Center Math. of Profile Inversion; 10 p
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 82
    Publication Date: 2011-08-16
    Description: The problems and potential of V/STOL transportation are examined. A detailed review is given of the development, characteristics, and requirements of V/STOL, STOL, and VTOL systems. The problem of whether V/STOL is worth the effort is considered, and it is concluded that such aircraft have a role in meeting real transport requirements, and that their development should be pursued. Finally, a forecast of V/STOL economics is presented, and implementation problems are discussed.
    Keywords: AIRCRAFT
    Type: Technology Review; 74; May 1972
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 83
    facet.materialart.
    Unknown
    In:  Other Sources
    Publication Date: 2011-08-16
    Description: Noise and congestion present the two main technological constraints on air-transportation growth. Although some of the noise reduction will come with improved flight-path control and steep approaches, the main requirement remains quiet propulsion systems. Higher engine temperatures will compensate for efficiency losses due to noise suppression. Composite structures can reduce structural weight by 20%. New developments in rotorcraft transports are discussed together with advanced subsonic transports of the 1980s and the possibilities for further evolution of the SSTs, leading to a hypersonic aircraft.
    Keywords: AIRCRAFT
    Type: Astronautics and Aeronautics; 10; Jan. 197
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 84
    facet.materialart.
    Unknown
    In:  Other Sources
    Publication Date: 2011-08-16
    Description: Observation of shadow bands during the solar eclipse of Mar. 7, 1970. Data were gathered by recording onto magnetic tape of the output from six collimated photocells whose spectral responses ranged from the ultraviolet to the infrared, and by visual and mechanical measurement of the orientation and motion of the bands. The recorded data were later processed using the output from a frequency spectrum analyzer. Most of the energy of the shadow bands ranges between 1 and 25 Hz, and appears not unlike plots of scintillation spectra. The onset, amplitude, and duration of the shadow bands seem to be spectrally related to the limb darkening of the sun's photosphere. Other results of the experiment conclusively indicate that the shadow band phenomenon is a manifestation of atmospheric turbulence in the form of air packets of different density from that of their environment (density schlieren), made visible by the light from the crescent sun.
    Keywords: GEOPHYSICS
    Type: Journal of Atmospheric and Terrestrial Physics; 34; Apr. 197
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 85
    Publication Date: 2011-08-16
    Description: Discussion of the technique of evaluating density values from precise radar-tracking data of satellites in the altitude region from 130 to 140 km. Inclinations of these satellites were between 106 and 112 deg. A detailed examination of all elements of the density-reduction techniques was conducted, and consideration was given to recent advances in geodesy, drag-coefficient modeling, and orbit-determination techniques. Ten days of high-resolution density data deduced from orbital decay of each of three satellites are presented. Three types of density variations at 140 km are discernible in these data: periodic daily density variations with a density amplitude of about 10%; density increases of up to 35% associated with enhanced geomagnetic activity during which the planetary geomagnetic index Kp reached a value of 8 units; and an observed semiannual variation of about 20%, which indicates a total semiannual variation of 35 to 40%.
    Keywords: GEOPHYSICS
    Type: Journal of Geophysical Research; 77; Apr. 1
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 86
    Publication Date: 2011-08-16
    Description: A review of engineering and research data requirements for altitudes 30-100 km is made, indicating a variety of concrete data applications above 30 km (10 mb). The required data have in large measure been provided from meteorological rocket soundings, of which 18,000 have been taken, at considerable cost, since 1959. Remote vertical soundings based on satellite infrared radiation measurements have been obtained since 1969 with considerable success to an altitude of 25 km (30 mb). From developmental work in progress, it is expected that reliable temperature soundings may be obtained to 40-45 km. A discussion of the overall reliability and utility of the satellite data leads to several conclusions regarding the continuing need for rocket soundings.
    Keywords: GEOPHYSICS
    Type: American Meteorological Society; vol. 53
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 87
    Publication Date: 2011-08-16
    Description: Black and white infrared imageries obtained from satellites over the oceans were transformed into color presentations. Investigations in different regions (Persian Gulf, Arabian Coast, Somali Coast and the Northwest Coast of Australia) revealed that temperature gradients and temperature differences of two degrees Celsius can be displayed by the color process from the imageries. This data display can be used for a rapid analysis of information obtained with an APT station.
    Keywords: GEOPHYSICS
    Type: Remote Sensing of Environment; 2; Feb. 197
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 88
    Publication Date: 2011-08-16
    Description: Evaluation of observations of surface temperature and salinity along the western edge of the Gulf Stream made from a ship and of concurrent temperature observations obtained by instrumented aircraft at six altitudes. The major feature along a five-kilometer line normal to the Stream's edge is a temperature gradient of about 0.75 C/kilometer within which are embedded two abrupt temperature increases of about 1.5 C. Temperature variations were compensated by salinity variations, yielding nearly constant density through the frontal zone; a sharp lateral current shear was associated with the thermohaline mixing region between the steps. The attenuation of surface temperature measured by the airborne radiometer was compared with a theoretical model. The analysis supports the view that a two-part correction technique is required: one part for bulk-skin temperature differences, and another for atmospheric attenuation of sea surface emission due to the mass and temperature of interfering gases.
    Keywords: GEOPHYSICS
    Type: Remote Sensing of Environment; 2; Feb. 197
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 89
    facet.materialart.
    Unknown
    In:  Other Sources
    Publication Date: 2011-08-16
    Description: The characteristics of midlatitude sporadic-E layers are observed using rocket payloads incorporating a probe and a propagation experiment. Layers below 120 km show evidence of preferred altitudes. The slopes of layers are within 1 deg of horizontal. The horizontal dimensions are deduced to be several hundred kilometers. Individual profiles of daytime layers show a range of shapes ranging from triangular to rectangular. The plasma frequency derived from the peak electron density in the layer is found to agree with the blanketing frequency given by the local ionosphere sounder.
    Keywords: GEOPHYSICS
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 90
    Publication Date: 2011-08-16
    Description: The use of IR aerial photographs for determining the dynamic characteristics of evapotranspiration at the Gila River Test Site is discussed. Evapotranspiration was measured as a function of plant volume, surface conditions, soil moisture storage, and ground water levels.
    Keywords: GEOPHYSICS
    Type: NASA. Manned Spacecraft Center 4th Ann. Earth Resources Program Rev., Vol. 3; 9 p
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 91
    Publication Date: 2011-08-16
    Description: A study was made of the spatial registration of fluoride and phosphate pollution parameters in central Florida by utilizing remote sensing techniques. Multispectral remote sensing data were collected over the area and processed to produce multispectral recognition maps. These processed data were used to map land areas and waters containing concentrations of fluoride and phosphate. Maps showing distribution of affected and unaffected vegetation were produced. In addition, the multispectral data were processed by single band radiometric slicing to produce radiometric maps used to delineate areas of high ultraviolet radiance, which indicates high fluoride concentrations. The multispectral parameter maps and radiometric maps in combination showed distinctive patterns, which are correlated with areas known to be affected by fluoride and phosphate contamination. These remote sensing techniques have the potential for regional use to assess the environmental impact of fluoride and phosphate wastes in central Florida.
    Keywords: GEOPHYSICS
    Type: NASA. Manned Spacecraft Center 4th Ann. Earth Resources Program Rev., Vol. 3; 12 p
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 92
    facet.materialart.
    Unknown
    In:  Other Sources
    Publication Date: 2011-08-16
    Description: Efforts to develop an automated system, from ERTS data, for producing computer models and computer maps of land use and other environmental factors for the Phoenix quadrangle are outlined.
    Keywords: GEOPHYSICS
    Type: NASA. Manned Spacecraft Center 4th Ann. Earth Resources Program Rev., Vol. 3; 19 p
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 93
    Publication Date: 2011-08-16
    Description: The functions, activities, and objectives of the Geography and Human-Cultural Resources Working Group of the EROS program are outlined. The Group's primary function is to coordinate remote sensing experiments of physical scientists and the needs of socioeconomic and culturally orientated planners, policy makers, administrators, and other user groups. Other functions of the Group include land use analysis, resource mapping, and development of an operational automatic information system receptive to land use and environmental data.
    Keywords: GEOPHYSICS
    Type: NASA. Manned Spacecraft Center 4th Ann. Earth Resources Program Rev., Vol. 3; 4 p
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 94
    facet.materialart.
    Unknown
    In:  Other Sources
    Publication Date: 2011-08-16
    Description: A specified approach to the automatic extraction and catographic presentation of thematic data contained in multispectral photographic images is presented. Experimental efforts were directed toward the mapping of open waters, snow and ice, infrared reflective vegetation, and massed works of man. The system must also be able to process data from a wide variety of sources.
    Keywords: GEOPHYSICS
    Type: NASA. Manned Spacecraft Center 4th Ann. Earth Resources Program Rev., Vol. 3; 13 p
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 95
    facet.materialart.
    Unknown
    In:  Other Sources
    Publication Date: 2011-08-16
    Description: Progress is reported on efforts to develop techniques of using space vehicle and high altitude aircraft imagery in cartography projects. Major efforts were made to develop an operational system for isolating specified themes from the imagery.
    Keywords: GEOPHYSICS
    Type: NASA. Manned Spacecraft Center 4th Ann. Earth Resources Program Rev., Vol. 3; 8 p
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 96
    facet.materialart.
    Unknown
    In:  Other Sources
    Publication Date: 2011-08-16
    Description: The use of remote sensing techniques by the Bureaus of Indian Affairs and Land Management in planning resource problems, making decisions, writing environmental impact statements, and monitoring their respective programs is investigated. For Indian affairs, data cover the Papago, Fort Apache, San Carlos, and South Dakota Reservations. For the Land Management Office, data cover cadastral surveys, California desert study, range watersheds, and efforts to establish a natural resources information system.
    Keywords: GEOPHYSICS
    Type: NASA. Manned Spacecraft Center 4th Ann. Earth Resources Program Rev., Vol. 3; 7 p
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 97
    Publication Date: 2011-08-16
    Description: Two clustering techniques were used for terrain mapping by computer of test sites in Yellowstone National Park. One test was made with multispectral scanner data using a composite technique which consists of (1) a strictly sequential statistical clustering which is a sequential variance analysis, and (2) a generalized K-means clustering. In this composite technique, the output of (1) is a first approximation of the cluster centers. This is the input to (2) which consists of steps to improve the determination of cluster centers by iterative procedures. Another test was made using the three emulsion layers of color-infrared aerial film as a three-band spectrometer. Relative film densities were analyzed using a simple clustering technique in three-color space. Important advantages of the clustering technique over conventional supervised computer programs are (1) human intervention, preparation time, and manipulation of data are reduced, (2) the computer map, gives unbiased indication of where best to select the reference ground control data, (3) use of easy to obtain inexpensive film, and (4) the geometric distortions can be easily rectified by simple standard photogrammetric techniques.
    Keywords: GEOPHYSICS
    Type: 4th Ann. Earth Resources Program Rev., Vol. 3; 30 p
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 98
    Publication Date: 2011-08-16
    Description: Results of Imp 5 magnetic-field measurements at geomagnetic latitudes up to 75 deg and at distances beyond six earth radii, revealing the permanent existence of a broad depressed field region centered on the polar or dayside cusp. Field strengths at seven earth radii on cusp field lines that connect to the earth are typically only 50 to 70% of that of an undistorted dipole field. The transition region between the magnetosheath and the point where the fields are clearly of dipolar origin is characterized by large-amplitude fluctuations and the lack of a clear magnetopause boundary. Magnetic-field perturbations are observed in the cusp region with magnitudes up to 45 gamma and in directions that are approximately perpendicular to the average field. These perturbations are suggestive of field-aligned currents, and their magnitudes are consistent with the low-altitude measurements obtained on polar-orbiting spacecraft.
    Keywords: GEOPHYSICS
    Type: Journal of Geophysical Research; 77; Feb. 1
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 99
    facet.materialart.
    Unknown
    In:  Other Sources
    Publication Date: 2011-08-16
    Description: The dynamics of tracked air-cushion vehicles considered for high-speed ground transportation systems are examined using a vehicle model represented by a one-degree-of-freedom system. The respective equations of motion are derived, and the control system is discussed. The equations obtained for the cushion are solved using an analog computer. The computer showed the effect of the control technique on the relative motion between vehicle and guideway.
    Keywords: AIRCRAFT
    Type: Instruments and Control Systems; 45; Apr. 197
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 100
    facet.materialart.
    Unknown
    In:  Other Sources
    Publication Date: 2011-08-16
    Description: A study of the internal structure of the neutral sheet in the geomagnetic tail has been made from data obtained by the NASA-GSFC magnetic-field experiment on the Explorer 34 spacecraft during its tail passage in the first half of 1968. The data used in the analysis are individual measurements of the vector magnetic field at 2.56-sec intervals. The experimental results consist of statistical studies of relevant properties of the magnetic field as a function of field magnitude. The results do not support nearly one-dimensional field models with characteristic lengths for field variation parallel to the neutral sheet much larger than the neutral-sheet width. The principal conclusion from the data points toward consistency with a quasi-periodic (possibly turbulent) structure with a tendency to formation of magnetic loops as one might expect from stability studies.
    Keywords: GEOPHYSICS
    Type: Journal of Geophysical Research; 77; Jan. 1
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...