329
329
Jun 26, 2011
06/11
by
Harl, Nathan; Pernicka, Henry J
texts
eye 329
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A method is presented for generating and maintaining a lunar mapping orbit using continuous low-thrust hardware. Optimal control theory is used to maintain a lunar orbit that is low-altitude, near-polar, and Sun-synchronous; three typical requirements for a successful lunar mapping mission. The analysis of the optimal control problem leads to the commonly seen two-point boundary value problem, which is solved using a simple indirect shooting algorithm. Simulations are presented for a 50-day...
Topics: WEAR, COMFORT, HELMETS, FIELD OF VIEW, SUITS, VISIBILITY, LAUNCHING, CREWS
216
216
May 31, 2011
05/11
by
Hakkinen, Sirp
texts
eye 216
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Both the observed and simulated time series of the Labrador Sea surface salinities show a major freshening event since the middles. It continues the series of decoder events of the 1970s and 1980s from which the freshening in the early 1970's was named as the Great Salinity Anomaly (GSA). These events are especially distinguishable in the late summer (August and September) time series. The observed data suggests that the 1990's freshening may equal the GSA in magnitude. This recent event is...
Topics: LEAF AREA INDEX, FIELD OF VIEW, MEASUREMENT, DEFOLIATION, VINEYARDS, VALLEYS, PLANTING
357
357
Sep 20, 2010
09/10
by
Blaes, V.; Mcintosh, R.; Roszman, L.; Cooley, J
texts
eye 357
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The results of an analysis of an algorithm that will provide autonomous onboard orbit control using orbits determined with Global Positioning System (GPS) data. The algorithm uses the GPS data to (1) compute the ground track error relative to a fixed longitude grid, and (2) determine the altitude adjustment required to correct the longitude error. A program was written on a personal computer (PC) to test the concept for numerous altitudes and values of solar flux using a simplified orbit model...
Topics: ASTRONOMICAL SPECTROSCOPY, DWARF NOVAE, FIELD OF VIEW, TARGETS, ROSAT MISSION, SKY SURVEYS...
379
379
Jun 13, 2011
06/11
by
Chima, Rodrick V
texts
eye 379
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A three-dimensional unsteady CFD code called CSTALL has been developed and used to investigate compressor stability. The code solved the Euler equations through the entire annulus and all blade rows. Blade row turning, losses, and deviation were modeled using body force terms which required input data at stations between blade rows. The input data was calculated using a separate Navier-Stokes turbomachinery analysis code run at one operating point near stall, and was scaled to other operating...
Topics: FIELD OF VIEW, KALMAN FILTERS, NEAR FIELDS, BORESIGHTS, TANGENTS, ATTITUDE (INCLINATION), FOCUSING,...
422
422
Jun 13, 2011
06/11
by
Batina, John T
texts
eye 422
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An advanced small perturbation (ASP) potential flow theory has been developed to improve upon the classical transonic small perturbation (TSP) theories that have been used in various computer codes. These computer codes are typically used for unsteady aerodynamic and aeroelastic analyses in the nonlinear transonic flight regime. The codes exploit the simplicity of stationary Cartesian meshes with the movement or deformation of the configuration under consideration incorporated into the solution...
Topics: LASER OUTPUTS, REMOTE SENSING, OPTICAL RADAR, LIGHT SOURCES, LIGHT BEAMS, FIELD OF VIEW, DETECTION,...
906
906
May 28, 2011
05/11
by
Litvin, F. L.; Egelja, A.; Tan, J.; Chen, D. Y.-D.; Heath, G
texts
eye 906
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The use of face gears in power transmission and drive systems has a significant number of benefits. Face gears allow a variety of new transmission arrangements as well as high reduction ratio capability. This leads to drive system weight reduction and improvements in performance. In this work, basic information about the design and analysis of face gear drives is presented. The work considers face gears in mesh with spur involute pinions for both intersecting axes and offset drives. Tooth...
Topics: DESIGN ANALYSIS, OPTICAL EQUIPMENT, OPTICAL RADAR, SYSTEMS ANALYSIS, TRADEOFFS, FRESNEL LENSES,...
206
206
Jun 3, 2011
06/11
by
Kahn, Ralph; Fukushima, Hajime, et al; Anderson, Jim; Anderson, Theodore L.; Bates, Tim; Brechtel, Fred; Clarke, Antony; Dutton, Ellsworth; Flagan, Richard; Fouin, Robert
texts
eye 206
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On five occasions spanning the ACE-Asia field experiment in spring 2001, the multi-angle imaging MISR instrument, flying aboard the NASA Earth Observing System s Terra satellite, took quarter-kilometer data over a 400-km-wide swath, coincident with high-quality observations by multiple instruments on two or more participating surface and airborne platforms. The cases capture a range of clean, polluted, and dusty aerosol conditions. They represent some of the best opportunities during ACE- Asia...
Topics: SEA-VIEWING WIDE FIELD-OF-VIEW SENSOR, MODIS (RADIOMETRY), MULTISENSOR FUSION, WATER COLOR,...
322
322
Jun 2, 2011
06/11
by
Luquette,Richard J.; Sanner, Robert M
texts
eye 322
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Precision Formation Flying is an enabling technology for a variety of proposed space-based observatories, including the Micro-Arcsecond X-ray Imaging Mission (MAXIM) , the associated MAXIM pathfinder mission, Stellar Imager (SI) and the Terrestrial Planet Finder (TPF). An essential element of the technology is the control algorithm, requiring a clear understanding of the dynamics of relative motion. This paper examines the dynamics of relative motion in the context of the Restricted Three Body...
Topics: WATER COLOR, OCEANS, SEA-VIEWING WIDE FIELD-OF-VIEW SENSOR, DATA PROCESSING, MODIS (RADIOMETRY),...
Helmet- and head-mounted display systems, denoted fiber-scanned microdisplays, have been proposed to provide information in an "augmented reality" format (meaning that the information would be optically overlaid on the user's field of view).
Topics: NASA Technical Reports Server (NTRS), HELMET MOUNTED DISPLAYS, OPTICAL FIBERS, FIELD OF VIEW,...
The IMAX camera system is used to record on-orbit activities of interest to the public. Because of the extremely high resolution of the IMAX camera, projector, and audio systems, the audience is afforded a motion picture experience unlike any other. IMAX and OMNIMAX motion picture systems were designed to create motion picture images of superior quality and audience impact. The IMAX camera is a 65 mm, single lens, reflex viewing design with a 15 perforation per frame horizontal pull across. The...
Topics: NASA Technical Reports Server (NTRS), CAMERAS, LENS DESIGN, PHOTOGRAPHIC FILM, PROJECTORS, FIELD OF...
An optical device having a semi-spherical or hemispherical field-of-view is provided. A conically-shaped piece of optical material has an annular surface satisfying Snell's Law for total internal reflection with respect to light passing through the piece and incident on the annular surface from within the piece.
Topics: NASA Technical Reports Server (NTRS), OPTICAL EQUIPMENT, REFRACTION, PATENTS, OPTICAL MATERIALS,...
362
362
May 22, 2011
05/11
by
Rivera, Jorge E.; Bowen, Barry C.; Davis, J. Bradley; Speece, Robert F
texts
eye 362
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A debris/ice/thermal protection system assessment and integrated photographic analysis was conducted for Shuttle mission STS-68. Debris inspections of the flight elements and launch pad were performed before and after launch. Icing conditions on the External Tank were assessed by the use of computer programs, nomographs, and infrared scanner data during cryogenic loading of the vehicle followed by on-pad visual inspection. High speed photography of the launch was analyzed to identify ice/debris...
Topics: SEYFERT GALAXIES, X RAY ASTRONOMY, X RAY BINARIES, X RAY SPECTRA, FIELD OF VIEW, IRON, OXYGEN,...
Robot Systems Technology Branch engineers at Johnson Space Center created the remotely controlled Robonaut for use as an additional "set of hands" in extravehicular activities (EVAs) and to allow exploration of environments that would be too dangerous or difficult for humans. One of the problems Robonaut developers encountered was that the robot s interface offered an extremely limited field of vision. Johnson robotics engineer, Darby Magruder, explained that the 40-degree...
Topics: NASA Technical Reports Server (NTRS), VIRTUAL REALITY, EXTRAVEHICULAR ACTIVITY, ROBOTICS,...
812
812
texts
eye 812
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The unprecedented advances being made in computational fluid dynamic (CFD) technology have demonstrated the powerful capabilities of codes in applications to civil and military aircraft. Used in conjunction with wind-tunnel and flight investigations, many codes are now routinely used by designers in diverse applications such as aerodynamic performance predictions and propulsion integration. Typically, these codes are most reliable for attached, steady, and predominantly turbulent flows. As a...
Topics: DISPLAY DEVICES, ENHANCED VISION, FIELD OF VIEW, FLIGHT SAFETY, SIMULATION, COMPUTER GRAPHICS,...
392
392
Sep 20, 2010
09/10
by
Wolverton, Bill C.; Richter, R.; Lefstad, Sandra M
texts
eye 392
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An organophosphorus insecticide decontaminating solution has been developed that can be used on and around aircraft and spray equipment. This solution converts the insecticides to products which can be disposed of by water washing without the extremely toxic effects to fish normally exhibited by the unaltered insecticides. The solvent component of this decontaminant is dispropylene glycol monomethyl ether (DPGME), a water-soluble, nonhazardous substance used in numerous commercial products. The...
Topics: CALIBRATING, RADIANCE, LUNAR OBSERVATORIES, QUALITY CONTROL, REMOTE SENSING, SOLAR OBSERVATORIES,...
804
804
Jul 25, 2010
07/10
by
Nielsen, Jack Norman; Kaattari, George E.; Anastasio, Robert F
texts
eye 804
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No Abstract Available
Topics: ERROR ANALYSIS, QUALITY CONTROL, TOLERANCES (MECHANICS), FIELD OF VIEW, IMAGING TECHNIQUES,...
186
186
May 23, 2011
05/11
by
McConley, Marc W.; Chubb, Donald L.; McMaster, Matthew S.; Afjeh, Abdollah A
texts
eye 186
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A two-dimensional, linear stability analysis of a thin nonplanar liquid sheet flow in vacuum is carried out. A sheet flow created by a narrow slit of W and tau attains a nonplanar cross section as a consequence of cylinders forming on the sheet edge under the influence of surface tension forces. The region where these edge cylinders join the sheet is one of high curvature, and this is found to be the location where instability is most likely to occur. The sheet flow is found to be unstable, but...
Topics: APPLICATIONS PROGRAMS (COMPUTERS), CROSS CORRELATION, BIDIRECTIONAL REFLECTANCE, IMAGING...
As the astronomical community moves ever more towards fewer and larger telescopes it is not just desirable but essential to make the maximum possible use of these new facilities. The Hitchhiker parallel CCD camera has been specially designed to increase the scientific output of a large telescope by imaging the off-axis field of view. The large data set collected by this instrument consists of deep CCD multicolor data of the distant Universe and is extremely well suited to the study of faint...
Topics: NASA Technical Reports Server (NTRS), ASTRONOMICAL PHOTOGRAPHY, CAMERAS, CHARGE COUPLED DEVICES,...
452
452
Jun 3, 2011
06/11
by
Kay-Bunnell, Lind
texts
eye 452
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The results presented show the level of orbit determination accuracy obtainable for long-period comets discovered approximately one year before collision with Earth. Preliminary orbits are determined from simulated observations using Gauss' method. Additional measurements are incorporated to improve the solution through the use of a Kalman filter, and include non-gravitational perturbations due to outgassing. Comparisons between observatories in several different circular heliocentric orbits...
Topics: GYRES, BIOGEOCHEMISTRY, GEOCHEMISTRY, ATLANTIC OCEAN, OPTICAL PROPERTIES, HYDROGRAPHY, OCEAN...
188
188
May 30, 2011
05/11
by
Wolpert, David H.; Sill, Joseph; Turner, Kaga
texts
eye 188
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Distributed search algorithms are crucial in dealing with large optimization problems, particularly when a centralized approach is not only impractical but infeasible. Many machine learning concepts have been applied to search algorithms in order to improve their effectiveness. In this article we present an algorithm that blends Reinforcement Learning (RL) and hill climbing directly, by using the RL signal to guide the exploration step of a hill climbing algorithm. We apply this algorithm to...
Topics: GAMMA RAY TELESCOPES, IMAGING TECHNIQUES, GAMMA RAY OBSERVATORY, SPACE MISSIONS, GAMMA RAY BURSTS,...
We can determine distances between objects and points of interest in 3-D space to a useful degree of accuracy from a set of camera images by using multiple camera views and reference targets in the camera s field of view (FOV). The core of the software processing is based on the previously developed foreign-object debris vision trajectory software (see KSC Research and Technology 2004 Annual Report, pp. 2 5). The current version of this photogrammetry software includes the ability to calculate...
Topics: NASA Technical Reports Server (NTRS), CAMERAS, PHOTOGRAMMETRY, FABRICATION, CUBIC LATTICES, FIELD...
428
428
May 27, 2011
05/11
by
Chow, Pao-Li
texts
eye 428
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In recent years, active and passive control of sound and vibration in aeroelastic structures have received a great deal of attention due to many potential applications to aerospace and other industries. There exists a great deal of research work done in this area. Recent advances in the control of sound and vibration can be found in the several conference proceedings. In this report we will summarize our research findings supported by the NASA grant NAG-1-1175. The problems of active and...
Topics: GLOBAL POSITIONING SYSTEM, APPROACH, NAVIGATION, SIMULATION, ANTENNA COMPONENTS, ATTITUDE...
391
391
May 30, 2011
05/11
by
Hall, Dorothy K.; Riggs, George A.; Salomonson, Vinvent V.; DiGirolamo, Nicolo; Bayr, Klaus J
texts
eye 391
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On December 18, 1999, the Terra satellite was launched with a complement of five instruments including the Moderate Resolution Imaging Spectroradiometer (MODIS). Many geophysical products are derived from MODIS data including global snow-cover products. These products have been available through the National Snow and Ice Data Center (NSIDC) Distributed Active Archive Center (DAAC) since September 13, 2000. MODIS snow-cover products represent potential improvement to the currently available...
Topics: CHLOROPHYLLS, OCEANOGRAPHY, PERIODIC VARIATIONS, ALGORITHMS, CARBON CYCLE, COASTAL ZONE COLOR...
We have recently reported on a theoretical digital signal-processing algorithm for improved energy and position resolution in position-sensitive, transition-edge sensor (POST) X-ray detectors [Smith et al., Nucl, lnstr and Meth. A 556 (2006) 2371. PoST's consists of one or more transition-edge sensors (TES's) on a large continuous or pixellated X-ray absorber and are under development as an alternative to arrays of single pixel TES's. PoST's provide a means to increase the field-of-view for the...
Topics: NASA Technical Reports Server (NTRS), SIGNAL PROCESSING, X RAY DETECTORS, CALORIMETERS, ALGORITHMS,...
Although many of their scientific interests overlap, current GeV and reV telescopes have many properties that show strong contrasts. Field of view, duty cycle, speed of analysis, photon counting statistics, background, and data release policies differ markedly. The challenge for cooperative studies has been to make the best use of complementary properties. One example is GeV discovery and monitoring surveys for AGN coupled with rev time variability studies. Another is GeV spectral measurements...
Topics: NASA Technical Reports Server (NTRS), TELESCOPES, SPECTRUM ANALYSIS, GAMMA RAYS, FIELD OF VIEW,...
An optical device having a semi-spherical or hemispherical field-of-view is provided. A conically-shaped piece of optical material has an annular surface satisfying Snell's Law for total internal reflection with respect to light passing through the piece and incident on the annular surface from within the piece.
Topics: NASA Technical Reports Server (NTRS), OPTICAL MATERIALS, REFRACTION, OPTICS, FIELD OF VIEW,...
342
342
Jun 12, 2011
06/11
by
Papatheodorou, Andreas; Busuttil, Loui
texts
eye 342
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Aviation deregulation is usually a challenging and demanding task and accession to the European Union requires that all candidate states should harmonize their legislation in the context of the European Common Aviation Area. Malta and Cyprus, the small Mediterranean island-states to join the EU in 2004, will have to abandon any protectionist policies in favour of their flag-carriers and let them survive in a liberal framework. The paper discusses the implications of this regime change for civil...
Topics: HOLOGRAPHIC OPTICAL ELEMENTS, AIRBORNE RADAR, DIFFRACTION, OPTICAL RADAR, TELESCOPES, CONICAL...
The onboard navigational system for the X-33 test flights will be based on the use of measurements collected from the Embedded Global Positioning System (GPS)/INS system. Some of the factors which will affect the quality of the GPS contribution to the navigational solution will be the number of pseudorange measurements collected at any instant in time, the distribution of the GPS satellites within the field of view, and the inherent noise level of the GPS receiver. The distribution of GPS...
Topics: NASA Technical Reports Server (NTRS), GLOBAL POSITIONING SYSTEM, SPACECRAFT TRAJECTORIES, FIELD OF...
Design methods are described for unobstructed, plane-symmetric, anamorphic systems composed of three mirrors. Low order imaging constraints are used to reduce the dimensionality of the configuration space. Examples are presented from a specific class of systems with fixed packaging constraints.
Topics: NASA Technical Reports Server (NTRS), MIRRORS, FIELD OF VIEW, IMAGING TECHNIQUES, SYMMETRY,...
234
234
May 31, 2011
05/11
by
Goyne, C. P.; McDaniel, J. C.; Krauss, R. H.; Day, S. W.; Reubush, D. E
texts
eye 234
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Temporally and spatially-resolved, two-component measurements of velocity in a supersonic hydrogen-air combustor are reported. The combustor had a single unswept ramp fuel injector and operated with an inlet Mach number of 2 and a flow total temperature approaching 1200 K. The experiment simulated the mixing and combustion processes of a dual-mode scramjet operating at a flight Mach number near 5. The velocity measurements were obtained by seeding the fuel with alumina particles and performing...
Topics: DISPLAY DEVICES, AIRPORT TOWERS, AIRCRAFT MANEUVERS, AIRCRAFT DETECTION, VISUAL FIELDS, FIELD OF...
The serendipitious WFC sources under investigation, i.e., those which just happened to lie in the field of view while another object was being studied, were disappointing. The integration times were chosen to suit the primary target not the serendipitous targets. UX UMa, CZ Ori, BI Ori, WX Cet and AR And were not detected. A long (approximately 17 ksec) pointed observation of UX Uma (PI Wood) has since been carried out (February 1993) and the data is expected shortly. The other observations...
Topics: NASA Technical Reports Server (NTRS), ASTRONOMICAL SPECTROSCOPY, DWARF NOVAE, FIELD OF VIEW,...
NASA offers companies an optical system that provides a unique panoramic perspective with a single camera. NASA's Marshall Space Flight Center has developed a technology that combines a panoramic refracting optic (PRO) lens with a unique detection system to acquire a true 360-degree field of view. Although current imaging systems can acquire panoramic images, they must use up to five cameras to obtain the full field of view. MSFC's technology obtains its panoramic images from one vantage point.
Topics: NASA Technical Reports Server (NTRS), FIELD OF VIEW, IMAGING TECHNIQUES, PANORAMIC CAMERAS,...
A particle size spectrometer having a fixed field of view within the forward light scattering cone at an angle .theta..sub.s between approximately 100 and 200 minutes of arc (preferably at 150 minutes), a spectral range extending approximately from 0.2 to 4.0 inverse micrometers (.mu.m.sup.-1), and a spectral resolution between about 0.1 and 0.2 .mu.m.sup.-1 (preferably toward the lower end of this range of spectral resolution), is employed to determine the distribution of particle sizes,...
Topics: NASA Technical Reports Server (NTRS), FIELD OF VIEW, FORWARD SCATTERING, FREQUENCY SCANNING, LIGHT...
520
520
May 23, 2011
05/11
by
McGowan, David Michae
texts
eye 520
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The analytical formulation of curved-plate non-linear equilibrium equations including transverse-shear-deformation effects is presented. The formulation uses the principle of virtual work. A unified set of non-linear strains that contains terms from both physical and tensorial strain measures is used. Linearized, perturbed equilibrium equations (stability equations) that describe the response of the plate just after buckling occurs are then derived after the application of several simplifying...
Topics: UPPER ATMOSPHERE, ACCUMULATORS, ANISOTROPY, GAMMA RAYS, TEMPORAL RESOLUTION, COSMIC RAY SHOWERS,...
A system that comprises optical and electronic subsystems has been developed as an infrastructure for a spectroradiometer that measures time-dependent spectral radiance of the daylight sky, in a narrow field of view (having angular width of the order of 1 ) centered on the zenith, in several spectral bands in the wavelength range from 0.3 to 2.2 m. This system is used in conjunction with two commercially available monolithic spectrometers: a silicon-based one for wavelengths from 0.3 to 1.1 m...
Topics: NASA Technical Reports Server (NTRS), COLLIMATORS, GALLIUM ARSENIDES, SPECTRAL BANDS,...
The purpose is to discuss the role of geometry in determining the perception of spatial layout and perceived orientation in pictures viewed at an angle. This discussion derives from Cutting's (1988) suggestion, based on his analysis of some of the author's data (Goldstein, 1987), that the changes in perceived orientation that occur when pictures are viewed at an angle can be explained in terms of geometrically produced changes in the picture's virtual space.
Topics: NASA Technical Reports Server (NTRS), ANGULAR RESOLUTION, FIELD OF VIEW, IMAGE ANALYSIS, VISUAL...
This paper will explore suitability of a newly available capacitance to digital converter for use in a 3D Electrical Capacitance Tomography system. A switch design is presented along with circuitry needed to extend the range of the capacitance to digital converter. Results are then discussed for a 15+ hour drift and noise test.
Topics: NASA Technical Reports Server (NTRS), CAPACITANCE, TOMOGRAPHY, DIELECTRICS, CIRCUITS, ELECTRODES,...
The Lyman Alpha Spicule Observatory (LASO) sounding rocket will observe smallscale eruptive events called "Rapid Blue-shifted Events" (RBEs) [Rouppe van der Voort et al., 2009], the on-disk equivalent of Type-II spicules, and extend observations that explore their role in the solar coronal heating problem [De Pontieu et al., 2011]. LASO utilizes a new and novel optical design to simultaneously observe two spatial dimensions at 4.2" spatial resolution (2.1" pixels) over a...
Topics: NASA Technical Reports Server (NTRS), LYMAN ALPHA RADIATION, SPICULES, OBSERVATORIES, SOUNDING...
We were awarded l00OkS of INTEGRAL spacecraft time (Priority A) to observe the ultraluminous infrared galaxy (ULIG) Mrk 2273 in order io measure the integrated flux of the 20-1003 KeV gamma-Ray emission, and to use this information to search for the presence of an highly obscured active galactic nucleus (AGN). With this observation we hope to be able to better assess the role of AGN in the complete class of ULIGs and therefore to better constrain their contribution to the hard X-ray and soft...
Topics: NASA Technical Reports Server (NTRS), ACTIVE GALACTIC NUCLEI, GALAXIES, LUMINOSITY, CAMERAS,...
175
175
Jun 2, 2011
06/11
by
Engblom, W. A
texts
eye 175
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Computational results are presented for the performance and flow behavior of single-expansion ramp nozzles (SERNs) during overexpanded operation and transonic flight. Three-dimensional Reynolds-Averaged Navier Stokes (RANS) results are obtained for two vehicle configurations, including the NASP Model 5B and ISTAR RBCC (a variant of X-43B) using the WIND code. Numerical predictions for nozzle integrated forces and pitch moments are directly compared to experimental data for the NASP Model 5B,...
Topics: BIOGEOCHEMISTRY, SARGASSO SEA, WATER COLOR, OCEAN SURFACE, ADVANCED VERY HIGH RESOLUTION...
Many factors affect the suitability of an out-the-window simulator visual system. Contrast, brightness, resolution, field-of-view, update rate, scene content and a number of other criteria are common factors often used to define requirements for simulator visual systems. For the past 7 years, NASA has worked with the USAF on the Operational Based Vision Assessment Program. The purpose of this program has been to provide the USAF School of Aerospace Medicine with a scientific testing laboratory...
Topics: NASA Technical Reports Server (NTRS), DESIGN ANALYSIS, FIELD OF VIEW, DISPLAY DEVICES, FLIGHT...
209
209
May 31, 2011
05/11
by
Huff, Dennis L
texts
eye 209
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History shows that the problem of high-speed jet noise reduction is difficult to solve. the good news is that high performance military aircraft noise is dominated by a single source called 'jet noise' (commercial aircraft have several sources). The bad news is that this source has been the subject of research for the past 50 years and progress has been incremental. Major jet noise reduction has been achieved through changing the cycle of the engine to reduce the jet exit velocity. Smaller...
Topics: SOLUBILITY, INTERNATIONAL SPACE STATION, SPACE FLIGHT, SPACEBORNE EXPERIMENTS, VELOCITY...
This paper describes the Analytical Spectral Devices (ASD) Fieldspec Calibration Setup and Techniques. The topics include: 1) ASD Fieldspec FR Spectroradiometer; 2) Components of Calibration; 3) Equipment list; 4) Spectral Setup; 5) Spectral Calibration; 6) Radiometric and Linearity Setup; 7) Radiometric setup; 8) Datadets Required; 9) Data files; and 10) Field of View Measurement. This paper is in viewgraph form.
Topics: NASA Technical Reports Server (NTRS), CALIBRATING, SPECTRORADIOMETERS, REMOTE SENSING, PORTABLE...
FRESIP Project observations of cataclysmic variables would provide unique data sets. In the study of known cataclysmic variables they would provide extended, well sampled temporal photometric information and in addition, they would provide a large area deep survey; obtaining a complete magnitude limited sample of the galaxy in the volume cone defined by the FRESIP field of view.
Topics: NASA Technical Reports Server (NTRS), CATACLYSMIC VARIABLES, FIELD OF VIEW, GALAXIES, PHOTOMETRY,...
492
492
Jul 12, 2010
07/10
by
Birks, N
texts
eye 492
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Sodium chloride is deposited on the surface of alumina substrates and exposed to air containing 1% SO2 at temperatures between 500 C and 700 C. In all cases the sodium chloride was converted to sodium sulfate. The volatilization of sodium chloride from the original salt particles was responsible for the development of a uniform coating of sodium sulfate on the alumina substrate. At temperatures above 625 C, a liquid NaCl-Na2SO4 autectic was formed on the substrate. The mechanisms for these...
Topics: SPACE RENDEZVOUS, TUMBLING MOTION, SPACECRAFT DOCKING, VIDEO EQUIPMENT, ANGULAR MOMENTUM, FIELD OF...
A display for producing a seamless composite image from at least two discrete images. The display includes one or more projectors for projecting each of the discrete images separately onto a screen such that at least one of the discrete images overlaps at least one other of the discrete images by more than 25 percent. The amount of overlap that is required to reduce the seams of the composite image to an acceptable level over a predetermined viewing angle depends on a number of factors...
Topics: NASA Technical Reports Server (NTRS), IMAGE PROCESSING, PHOTOMAPPING, DISPLAY DEVICES, FIELD OF...
266
266
May 31, 2011
05/11
by
Li, Jian-Zhong; Cheung, Samson H.; Ning, C. Z
texts
eye 266
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Electron and hole diffusions in the plane of semiconductor quantum wells play an important part in the static and dynamic operations of semiconductor lasers. It is well known that the value of diffusion coefficients affects the threshold pumping current of a semiconductor laser. At the same time, the strength of carrier diffusion process is expected to affect the modulation bandwidth of an AC-modulated laser. It is important not only to investigate the combined DC and AC effects due to carrier...
Topics: IRRADIANCE, CALIBRATING, SEA-VIEWING WIDE FIELD-OF-VIEW SENSOR, OCEAN SURFACE, OPTICAL PROPERTIES,...
A viewgraph presentation describing maintenance procedures for head mounted displays is shown. The topics include: 1) Study Goals; 2) Near Eye Displays (HMDs); 3) Design; 4) Phase I-Evaluation Methods; 5) Phase 1 Results; 6) Improved HMD Mounting; 7) Phase 2 -Evaluation Methods; 8) Phase 2 Preliminary Results; and 9) Next Steps.
Topics: NASA Technical Reports Server (NTRS), HEAD-UP DISPLAYS, MAINTENANCE, SYSTEMS INTEGRATION,...
Two studies were performed to determine whether a subject's response to naturalistic optical flow specifying egomotion would be affected by a concurrent attention task. In the first study subjects stood in a moving room in which various areas of the optical flow generated by room movement were visible. Subjects responded to room motion with strong compensatory sway when the entire room was visible. When the side walls of the room were completely obscured by stationary screens, leaving only the...
Topics: NASA Technical Reports Server (NTRS), CUES, MOTION PERCEPTION, VISUAL STIMULI, COMPENSATION, FIELD...
254
254
Jun 13, 2011
06/11
by
Stohlgren, Tom; Schnase, John; Morisette, Jeffrey; Most, Neal; Sheffner, Ed; Hutchinson, Charles; Drake, Sam; Van Leeuwen, Willem; Kaupp, Vern
texts
eye 254
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The National Institute of Invasive Species Science (NIISS), through collaboration with NASA's Goddard Space Flight Center (GSFC), recently began incorporating NASA observations and predictive modeling tools to fulfill its mission. These enhancements, labeled collectively as the Invasive Species Forecasting System (ISFS), are now in place in the NIISS in their initial state (V1.0). The ISFS is the primary decision support tool of the NIISS for the management and control of invasive species on...
Topics: GAMMA RAY BURSTS, TARGET ACQUISITION, SWIFT OBSERVATORY, X RAY TELESCOPES, FIELD OF VIEW,...
