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The use of continuum models for the analysis of discrete built-up complex aerospace structures is an attractive idea especially at the conceptual and preliminary design stages. But the diversity of available continuum models and hard-to-use qualities of these models have prevented them from finding wide applications. In this regard, Artificial Neural Networks (ANN or NN) may have a great potential as these networks are universal approximators that can realize any continuous mapping, and can...
Topics: NASA Technical Reports Server (NTRS), NEURAL NETS, STRUCTURAL ENGINEERING, AEROSPACE ENGINEERING,...
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Described are methods and apparatus, including computer program products, for reconfigurable environmentally adaptive computing technology. An environmental signal representative of an external environmental condition is received. A processing configuration is automatically selected, based on the environmental signal, from a plurality of processing configurations. A reconfigurable processing element is reconfigured to operate according to the selected processing configuration. In some examples,...
Topics: NASA Technical Reports Server (NTRS), COMPUTATION, COMPUTER PROGRAMS, COMPUTERS, COMPUTER SYSTEMS...
NASA is interested in finding new methods of surface navigation to allow astronauts to navigate on the lunar surface. In support of the Vision for Space Exploration, the NASA Glenn Research Center developed the Lunar Extra-Vehicular Activity Crewmember Location Determination System and performed testing at the Desert Research and Technology Studies event in 2009. A significant amount of sensor data was recorded during nine tests performed with six test subjects. This paper provides the...
Topics: NASA Technical Reports Server (NTRS), LUNAR SURFACE, SURFACE NAVIGATION, SPACE EXPLORATION,...
The new NASA Vision for Exploration, announced by President Bush in January 2004, proposes an ambitious program that plans to return astronauts to the moon by the 2018 time frame. A recent NASA study entitled "Affordable Fission Surface Power Study" recommended a 40 kWe, 900 K, NaK-cooled, Stirling convertors for 2020 launch. Use of two of the nominal 5 kW convertors allows the system to be dynamically balanced. A group of four dual-convertor combinations that would yield 40 kWe can...
Topics: NASA Technical Reports Server (NTRS), STIRLING CYCLE, SPACECRAFT POWER SUPPLIES, FREE-PISTON...
One-watt refrigerator used for attaining clean room conditions in vacuum system of space simulator
Topic: NASA Technical Reports Server (NTRS)
NASA contributions to bioinstrumentation system - survey
Topic: NASA Technical Reports Server (NTRS)
Micromicroampere current measuring circuit, with two subminiature thermionic diodes with filament cathodes
Topic: NASA Technical Reports Server (NTRS)
The results are presented of a study initiated to evaluate the star tracker axis-to-sunlit earth horizon angle constraint with respect to limitations imposed on the passive target rendezvous capability. The data presented include considerations for dispersions and sensor pointing capabilities and generalizations with respect to the uncertainties associated with the angle constraint available in practice.
Topics: NASA Technical Reports Server (NTRS), EARTH ORBITAL RENDEZVOUS, RENDEZVOUS GUIDANCE, STAR TRACKERS,...
Computer programs to calculate the incompressible potential flow, corrected for compressibility, in two-dimensional nozzles at arbitrary operating conditions are presented. A statement of the problem to be solved, a description of each of the computer programs, and sufficient documentation, including a test case, to enable a user to run the program are included.
Topics: NASA Technical Reports Server (NTRS), COMPUTER PROGRAMS, NOZZLE FLOW, NOZZLE GEOMETRY, POTENTIAL...
The computer programs for the CDC version of SIMWEST (1979 revision) are described. Macro flow charts and source code listings for each major program entity are presented.
Topics: NASA Technical Reports Server (NTRS), CDC COMPUTERS, COMPUTERIZED SIMULATION, ENERGY STORAGE,...
Schlieren photographs have been compiled of the two-dimensional flow at transonic speeds past 37 airfoils. These airfoils have variously shaped profiles, and some are related in thickness and camber. The data for these airfoils were analyzed to provide basic information on the flow changes involved and to determine factors affecting transonic-flow attachment, which is a transition from separated to unseparated flow at the leading edges of two-dimensional airfoils at fixed angles as the subsonic...
Topic: NASA Technical Reports Server (NTRS)
This report presents two numerical methods considered for the computation of fuel-optimal, low-thrust orbit transfers in large numbers of burns. The origins of these methods are observations made with the extremal solutions of transfers in small numbers of burns; there seems to exist a trend such that the longer the time allowed to perform an optimal transfer the less fuel that is used. These longer transfers are obviously of interest since they require a motor of low thrust; however, we also...
Topics: NASA Technical Reports Server (NTRS), BURNING RATE, COMBUSTION EFFICIENCY, FUEL CONSUMPTION,...
The Geostationary Operational Environmental Satellite R (GOES-R) series is the planned next generation of operational weather satellites for the United States National Oceanic and Atmospheric Administration (NOAA). The National Aeronautics and Space Administration (NASA) is procuring the GOES-R spacecraft and instruments with the first launch of the GOES-R series planned for October 2016. Included in the GOES-R Instrument suite is the Geostationary Lightning Mapper (GLM). GLM is a...
Topics: ASRC Federal Space and Defense, Cholvibul, Ruth, Clarke, Jared, Orbital Sciences Corp., Rafal,...
The CERES SYN1deg product provides climate quality 3-hourly globally gridded and temporally complete maps of top of atmosphere, in atmosphere, and surface fluxes. This product requires efficient release to the public and validation to maintain quality assurance. The CERES team developed web-tools for the distribution of both the global gridded products and grid boxes that contain long term validation sites that maintain high quality flux observations at the Earth's surface. These are found at:...
Topics: Doelling, David, Kato, Seiji, Mitrescu, Cristian, NASA Langley Research Center, Rutan, David,...
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Results of a hardware vs. software correlation of the RDV77 session are presented. Group delays are found to agree (WRMS differences) at an average level of 4.2 psec and with a noise floor of 2.5 psec. These RDV77 comparisons agree well with several previous correlator comparison studies.
Topics: NASA Technical Reports Server (NTRS), VERY LONG BASE INTERFEROMETRY, COMPUTER PROGRAMS,...
Measurements of the temperature profiles in an RF argon plasma were made over magnetic field intensities ranging from 20 amp turns/cm to 80 amp turns/cm. The results were compared with a one-dimensional numerical treatment of the governing equations and with an approximate closed form analytical solution that neglected radiation losses. The average measured temperatures in the plasma compared well with the numerical treatment, though the experimental profile showed less of an off center...
Topics: NASA Technical Reports Server (NTRS), ARGON PLASMA, GASEOUS FISSION REACTORS, PLASMA DIAGNOSTICS,...
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The theory of Massera and Schaeffer relating the existence of unique almost periodic solutions of an inhomogeneous linear equation to an exponential dichotomy for the homogeneous equation was completely extended to discretizations by a strongly stable difference scheme. In addition it is shown that the almost periodic sequence solution will converge to the differential equation solution. The preceding theory was applied to a class of exponentially stable partial differential equations to which...
Topics: NASA Technical Reports Server (NTRS), DIFFERENCE EQUATIONS, PARTIAL DIFFERENTIAL EQUATIONS, PROBLEM...
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Auroral studies are presented of flight data analysis from the Michigan airglow payload. Analysis of the stellar occultation data and results from the twilight flight are reported. Optical emissions from bottled aurora and an electron analyzer for measurement of distributions in energy of electrons along a beam are also presented. A list of related publications is included.
Topics: NASA Technical Reports Server (NTRS), AIRGLOW, AURORAS, LIGHT EMISSION, DATA PROCESSING, DATA...
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by NASA Technical Reports Server (NTRS)
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The Golstone Energy Project was established in 1974 to investigate ways in which the Goldstone Deep Space Complex in California could be made partly or completely energy-sufficient, especially through the use of solar- and wind-derived energy resources. Ways in which energy could be conserved at the Complex were also studied. Findings included data on both wind and solar energy. Obstacles to demonstrating energy self-sufficiency are: (1) operation and maintenance costs of solar energy systems...
Topics: NASA Technical Reports Server (NTRS), ECONOMIC ANALYSIS, ENERGY CONSERVATION, PROJECT PLANNING,...
Findings and conclusions derived during the study of freighter aircraft requirements to the year 2008 are summarized. These results represent the stepping off point for the much needed coordinated planning efforts by government agencies, the airlines, the users, and the aircraft manufacturers. The methodology utilized in the investigations is shown. The analysis of the current system encompassed evaluations of the past and current cargo markets and on sight surveys of airport and cargo...
Topics: NASA Technical Reports Server (NTRS), AIR CARGO, AIRLINE OPERATIONS, LOGISTICS MANAGEMENT, MARKET...
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A structured device placed in an aerated crucible to pack ceramics molding substance that is to be processed was designed. The structure is wrapped by sealing material made of pyrex glass and graphite foil or sheet with a weight attached on top of it. The crucible is made of carbon; the ceramics material to be treated through heat intervenient press process is molding substance consisting mainly of silicon nitride.
Topics: NASA Technical Reports Server (NTRS), BOROSILICATE GLASS, CERAMICS, MELTING POINTS, MOLDING...
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by NASA Technical Reports Server (NTRS)
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A GPS-based pitot-static calibration system uses global output-error optimization. High data rate measurements of static and total pressure, ambient air conditions, and GPS-based ground speed measurements are used to compute pitot-static pressure errors over a range of airspeed. System identification methods rapidly compute optimal pressure error models with defined confidence intervals.
Topics: 5fe35dc7ef634145a64392eca0efb517, 64c4a357d1c54e0b9d256dedb5451131, Cunningham, Kevin, Foster, John...
The RAPTR was developed to test ISS payloads for NASA. RAPTR is a simulation of the Command and Data Handling (C&DH) interfaces of the ISS (MIL-STD1553B, Ethernet and TAXI) and is designed for rapid testing and deployment of payload experiments to the ISS. The ISS's goal is to reduce the amount of time it takes for a payload developer to build, test and fly a payload, including payload software. The RAPTR meets this need with its user oriented, visually rich interface.
Topics: Boeing Co., De La Cruz, Melinda, Henderson, Steve, NASA Marshall Space Flight Center
This paper presents one-of-a-kind MPI-parallel computational fluid dynamics simulations for the Stratospheric Observatory for Infrared Astronomy (SOFIA). SOFIA is an airborne, 2.5-meter infrared telescope mounted in an open cavity in the aft of a Boeing 747SP. These simulations focus on how the unsteady flow field inside and over the cavity interferes with the optical path and mounting of the telescope. A temporally fourth-order Runge-Kutta, and spatially fifth-order WENO-5Z scheme was used to...
Topics: Barad, Michael F., Biswas, Rupak, Brehm, Christoph, Kiris, Cetin C., NASA Ames Research Center,...
A method for providing a perfectly flat top with a sharp edge on a dynamic pressure sensor using a cup-shaped stretched membrane as a sensing element is described. First, metal is deposited on the membrane and surrounding areas. Next, the side wall of the pressure sensor with the deposited metal is machined to a predetermined size. Finally, deposited metal is removed from the top of the membrane in small steps, by machining or lapping while the pressure sensor is mounted in a jig or the wall of...
Topics: NASA Technical Reports Server (NTRS), DYNAMIC PRESSURE, FLOW MEASUREMENT, PRESSURE MEASUREMENT,...
Upon observing an abnormal closure of the Space Shuttle s External Tank Doors (ETD), a dynamic model was created in MSC/ADAMS to conduct deflection analyses of the Door Drive Mechanism (DDM). For a similar analysis, the traditional approach would be to construct a full finite element model of the mechanism. The purpose of this paper is to describe an alternative approach that models the flexibility of the DDM using a lumped parameter approximation to capture the compliance of individual parts...
Topics: NASA Technical Reports Server (NTRS), DYNAMIC MODELS, EXTERNAL TANKS, CONSTRUCTION, SPACE SHUTTLES,...
Experiments and flight tests have shown that a Head-Up Display (HUD) and a head-down electronic moving map (EMM) can be enhanced with Synthetic Vision for airport surface operations. While great success in ground operations was demonstrated with a HUD, the research noted that two major HUD limitations during ground operations were its monochrome form and limited, fixed field-of-regard. A potential solution to these limitations found with HUDs may be emerging with Head Worn Displays (HWDs). HWDs...
Topics: NASA Technical Reports Server (NTRS), HEAD-UP DISPLAYS, ENHANCED VISION, PILOT PERFORMANCE, DISPLAY...
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The goal of the current evaluation was to examine five different wet-bath architectural design concepts. The primary means of testing the concepts required participants to physically act-out a number of functional tasks (e.g., shaving, showering, changing clothes, maintenance) in order to give judgments on the affordance of the volume as based on the design concepts. Each of the concepts was designed in such a way that certain features were exploited - for example, a concept may have a large...
Topics: NASA Technical Reports Server (NTRS), BATHS, LUNAR SURFACE, SYSTEMS ENGINEERING, HABITATS,...
The members of the phosphatidylinositol kinase-like kinase family of proteins namely ataxia-telangiectasia mutated (ATM) and ATM- and Rad3-related (ATR) are directly responsible for the maintenance of genomic integrity by mounting DDR through signaling and facilitating the recruitment of repair factors at the sites of DNA damage along with coordinating the deployment of cell cycle checkpoints to permit repair by phosphorylating Checkpoint kinase Chk1, Chk2 and p53. High LET radiation from GCR...
Topics: NASA Technical Reports Server (NTRS), DEOXYRIBONUCLEIC ACID, PROTEINS, CHARGED PARTICLES,...
Since astronauts on future deep space missions will be exposed to dangerous radiations, there is a need to accurately model the transport of radiation through shielding materials and to estimate the received radiation dose. In response to this need a three dimensional deterministic code for space radiation transport is now under development. The new code GRNTRN is based on a Green's function solution of the Boltzmann transport equation that is constructed in the form of a Neumann series....
Topics: NASA Technical Reports Server (NTRS), RADIATION TRANSPORT, EXTRATERRESTRIAL RADIATION, BOLTZMANN...
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A process has been developed that can confer novel properties, such as metal resistance, to a host bacterium. This same process can also be used to produce RNAs and peptides that have novel properties, such as the ability to bind particular compounds. It is inherent in the method that the peptide or RNA will behave as expected in the target organism. Plasmid-born mini-gene libraries coding for either a population of combinatorial peptides or stable, artificial RNAs carrying random inserts are...
Topics: NASA Technical Reports Server (NTRS), PHENOTYPE, RIBONUCLEIC ACIDS, PEPTIDES, BACTERIA, IN VITRO...
We report the Fermi Large Area Telescope detection of gamma -ray (>100 mega-electron volts) pulsations from pulsar J1823--3021A in the globular cluster NGC 6624 with high significance (approx 7 sigma). Its gamma-ray luminosity L (sub 3) = (8:4 +/- 1:6) X 10(exp 34) ergs per second, is the highest observed for any millisecond pulsar (MSP) to date, and it accounts for most of the cluster emission. The non-detection of the cluster in the off-pulse phase implies that its contains < 32...
Topics: NASA Technical Reports Server (NTRS), GLOBULAR CLUSTERS, LUMINOSITY, PULSARS, GAMMA RAY ASTRONOMY,...
INTRODUCTION. Some manufacturers of reduced oxygen (O2) breathing devices claim a comparable hypobaric hypoxia (HH) training experience by providing F(sub I) O2 < 0.209 at or near sea level pressure to match the ambient O2 partial pressure (iso-pO2) of the target altitude. METHODS. Literature from investigators and manufacturers indicate that these devices may not properly account for the 47 mmHg of water vapor partial pressure that reduces the inspired partial pressure of O2 (P(sub I)...
Topics: NASA Technical Reports Server (NTRS), HYPOXIA, OXYGEN BREATHING, HYPOBARIC ATMOSPHERES, RESPIRATORY...
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Nondestructive radiographic tests of resistance welds
Topic: NASA Technical Reports Server (NTRS)
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There are no author-identified significant results in this report. ERTS-1 information will be utilized by resource management groups working in the fields of forestry, hydrology, range management, and agriculture to develop resource inventories of the state of California. Five examples are given of the use of ERTS-1 imagery and aerial photography in identifying different crops and field conditions.
Topics: NASA Technical Reports Server (NTRS), CALIFORNIA, INVENTORIES, LANDSAT 1, RESOURCES MANAGEMENT,...
A condensation refrigerator suitable for operation in a zero gravity space environment was constructed. The condensed liquid refrigerant is confined by surface tension inside a porous metal matrix. Helium-4 and helium-3 gases were condensed and held in a copper matrix. Evaporative cooling of confined liquid helium-4 resulted in a temperature of 1.4K. Using a zeolite adsorption pump external to the cryostat, a temperature of 0.6 K was achieved through evaporative cooling of liquid helium-3. The...
Topics: NASA Technical Reports Server (NTRS), CRYOGENICS, LIQUID COOLING, LIQUID HELIUM, REFRIGERANTS,...
The on-orbit phase of flight was analyzed to identify the functions that had to be performed to meet flight objectives. The functions identified were combined into a top-level functional flow diagram (3.0 On-Orbit Operations). Each function, in turn, was analyzed to determine the major activities necessary to perform the function. The activities and activity sequences were presented in second level functional flow diagrams. Each major activity was further analyzed to define the operator tasks...
Topics: NASA Technical Reports Server (NTRS), COSTS, ECONOMIC FACTORS, FLIGHT TRAINING, OPERATIONS...
Dual variable-capacitance tachometer measures angular speed and sense of rotation without magnetic components. Thus it eliminates magnetic flux interference with associated instrumentation in an electromechanical system.
Topic: NASA Technical Reports Server (NTRS)
A computer program is presented which calculates the cutter location file needed to machine models of airplane wings or wing-fuselage combinations on numerically controlled machine tools. Input to the program is a data file consisting of coordinates on the fuselage and wing. From this data file, the program calculates tool offsets, determines the intersection between wing and fuselage tool paths, and generates additional information needed to machine the fuselage and/or wing. Output from the...
Topics: NASA Technical Reports Server (NTRS), AIRCRAFT MODELS, COMPUTER SYSTEMS PROGRAMS, USER MANUALS...
Solidification rate effect on beta phase in 5456 aluminum alloy
Topic: NASA Technical Reports Server (NTRS)
Specimen thermionic emitters were electropolished and electroetched to study the effect of surface preparations on improving thermionic emission. The best technique found was to electropolish the annealed rhenium surface and then electroetch it. The effect of electroetching was to remove other crystal planes faster than basal planes.
Topic: NASA Technical Reports Server (NTRS)
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Document presents optical-data processing information on a level which will convey the basic principles involved to those having a general technical background. Mathematical discussions are included but are not required for a basic understanding.
Topic: NASA Technical Reports Server (NTRS)
Superpressure mylar balloon technology in United States - applications, balloon size criteria, and possible improvements
Topic: NASA Technical Reports Server (NTRS)
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Explorer 35 measurement data analysis for magnetic properties of lunar body
Topic: NASA Technical Reports Server (NTRS)
Small amplitude solutions to spatially uniform plasma continuity equations for low frequency oscillations in electron density and neutral atoms
Topic: NASA Technical Reports Server (NTRS)
A pair feeding method and apparatus are provided for experimental animals wherein the amount of food consumed is immediately delivered to a normal or control animal so that there is a qualitative, quantitative and chronological correctness in the pair feeding of the two animals. This feeding mechanism delivers precisely measured amounts of food to a feeder. Circuitry is provided between master and slave feeders so that there is virtually no chance of a malfunction of the feeding apparatus,...
Topics: NASA Technical Reports Server (NTRS), ANIMALS, FEEDERS, LABORATORY EQUIPMENT, BIOENGINEERING,...
Silicon members are hermetically sealed to each other. Process produces no measurable deformation of silicon surfaces and is compatible with package designs of tight tolerance. Seals have been made with glass coatings in 10-mm to 20-mm thickness range without any prior annealing of coated silicon substrates.
Topics: NASA Technical Reports Server (NTRS), BOROSILICATE GLASS, ELECTRONIC PACKAGING, ELECTROSTATICS, LOW...
Fault-tolerant multiprocessor (FTMP) operation is discussed. Fault-modeling in the bus guardian units (BGUs) is covered. Testing the BGU is discussed. A testing algorithm is proposed.
Topics: NASA Technical Reports Server (NTRS), BUS CONDUCTORS, FAULT TOLERANCE, MULTIPROCESSING (COMPUTERS),...
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Initial results obtained from the registration of LANDSAT-4 MSS data to LANDSAT-2 MSS data are documented and compared with results obtained from a LANDSAT-2 MSS-to-LANDSAT-2 MSS scene-to-scene registration (using the same LANDSAT-2 MSS data as the base data set in both procedures). RMS errors calculated on the control points used in the establishment of scene-to-scene mapping equations are compared to errors computed from independently chosen verification points. Models developed to estimate...
Topics: NASA Technical Reports Server (NTRS), LANDSAT 4, MULTISPECTRAL BAND SCANNERS, PATTERN REGISTRATION,...
Citations are presented for 1380 for formal reports; quick-release technical memorandum; contractor reports; journal articles and periodical literature; technical talks and meeting presentations; computer programs; tech briefs, and patents produced during 1982. An author index is provided.
Topics: NASA Technical Reports Server (NTRS), AERODYNAMICS, AERONAUTICAL ENGINEERING, AEROSPACE...
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This directory lists the technical capabilities, personnel, and program structure for remote sensing activities as they existed in each state in late 1980. The institutional framework, participating agencies, applications, status, equipment, software, and funding sources are also indicated.
Topics: NASA Technical Reports Server (NTRS), DIRECTORIES, ENVIRONMENTAL MONITORING, REMOTE SENSING,...
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An analytical model was developed to predict the interior noise of propeller-driven aircraft. The fuselage model is that of a cylinder with a structurally-integral floor. The cabin sidewall is stiffened by stringers and ring frames, and the floor by longitudinal beams. The cabin interior is covered with a sidewall treatments consisting of layers of porous material and an impervious trim septum. Representation of the propeller pressure field is utilized as input data in the form of the propeller...
Topics: NASA Technical Reports Server (NTRS), AIRCRAFT COMPARTMENTS, AIRCRAFT NOISE, NOISE REDUCTION,...
A unified method is presented for deriving the influence functions of moving singularities which determine the field quantities in aerodynamics and aeroacoustics. The moving singularities comprise volume and surface distributions having arbitrary orientations in space and to the trajectory. Hence one generally valid formula for the influence functions which reveal some universal relationships and remarkable properties in the disturbance fields. The derivations used are completely consistent...
Topics: NASA Technical Reports Server (NTRS), AEROACOUSTICS, AERODYNAMICS, CORRELATION, KINEMATICS,...
The technical effort and computer code developed during the first year are summarized. Several formulations for Probabilistic Finite Element Analysis (PFEA) are described with emphasis on the selected formulation. The strategies being implemented in the first-version computer code to perform linear, elastic PFEA is described. The results of a series of select Space Shuttle Main Engine (SSME) component surveys are presented. These results identify the critical components and provide the...
Topics: NASA Technical Reports Server (NTRS), COMPUTER PROGRAMS, ENGINE PARTS, FINITE ELEMENT METHOD,...
Topic: NASA Technical Reports Server (NTRS)
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There has been intensive research in neural network applications to pattern recognition problems. Particularly, the back-propagation network has attracted many researchers because of its outstanding performance in pattern recognition applications. In this section, we describe a new method to generate membership functions from training data using a multilayer neural network. The basic idea behind the approach is as follows. The output values of a sigmoid activation function of a neuron bear...
Topics: NASA Technical Reports Server (NTRS), ALGORITHMS, COMPUTER VISION, FUZZY SETS, HEURISTIC METHODS,...
Topic: NASA Technical Reports Server (NTRS)
Topic: NASA Technical Reports Server (NTRS)
Curation of extraterrestrial samples is the critical interface between sample return missions and the international research community. The Astromaterials Acquisition and Curation Office at the NASA Johnson Space Center (JSC) is responsible for curating NASA's extraterrestrial samples. Under the governing document, NASA Policy Directive (NPD) 7100.10E "Curation of Extraterrestrial Materials," JSC is charged with ". . . curation of all extraterrestrial material under NASA control,...
Topics: NASA Technical Reports Server (NTRS), EXTRATERRESTRIAL MATTER, NASA PROGRAMS, SAMPLE RETURN...
We have been studying the backscatter ratio of the two CALIPSO wavelengths for 3 different targets. We are showing the ratio of integrate attenuated backscatter coefficient for cirrus clouds, ocean surface and liquid. Water clouds for one month of nightime data (left:July,right:December), Only opaque cirrus classified as randomly oriented ice[1] are used. For ocean and water clouds, only the clearest shots, determined by a threshold on integrated attenuated backscatter are used. Two things can...
Topics: NASA Technical Reports Server (NTRS), CALIBRATING, OPTICAL RADAR, SCATTERING COEFFICIENTS, ICE...
Orthostatic intolerance after space flight is still an issue for astronaut health. No in-flight countermeasure has been 100% effective to date. NASA currently uses an inflatable anti-gravity suit (AGS) during reentry, but this device is uncomfortable and loses effectiveness upon egress from the Shuttle. The Russian Space Agency currently uses a mechanical counter-pressure garment (Kentavr) that is difficult to adjust alone, and prolonged use may result in painful swelling at points where the...
Topics: NASA Technical Reports Server (NTRS), GARMENTS, ORTHOSTATIC TOLERANCE, ASTRONAUTS, CARDIOVASCULAR...
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by NASA Technical Reports Server (NTRS)
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Concerns have been raised about the possible connections between the local and regional photochemical problem and global warming. The current study assesses the trend of ozone in Hong Kong and the Pearl River Delta (PRD) in South China and investigates the interannual changes of sensitivity of ozone to air temperature, as well as the trends in regional precursors. Results reveal, at the three monitoring sites from the mid-1990s to 2010, an increase in the mean ozone concentrations from 1.0 to...
Topics: 0000-0001-9011-3663, City Univ. of Hong Kong, Columbia Univ., Hao, S., Lai, C. S., Lam, Y. F., Lee,...
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by NASA Technical Reports Server (NTRS)
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Low-leakage, long-life turbomachinery seals are important to both Space and Aeronautics Missions. (1) Increased payload capability (2) Decreased specific fuel consumption and emissions (3) Decreased direct operating costs. NASA GRC has a history of significant accomplishments and collaboration with industry and academia in seals research. NASA's unique, state-of-the-art High Temperature, High Speed Turbine Seal Test Facility is an asset to the U.S. Engine / Seal Community. Current focus is on...
Topics: NASA Technical Reports Server (NTRS), TURBINES, SEALS (STOPPERS), HIGH TEMPERATURE, LEAKAGE, FLUID...
The potential risk of injury to crewmembers is inherent in aggressive surface activities, whether they be Moon-, Mars-, or asteroid-based. In December 2005, the Space Medicine Division at JSC requested a study to identify Apollo mission issues that had an impact to crew health or performance or both. This talk focused on the Apollo EVA suit and lunar surface operations concerning crew health and performance. There were roughly 20 recommendations from this study of Apollo for improving these two...
Topics: Chicago Univ., Davis, J. R., Duncan, J. M., Gillis, D. B., Jones, J. A., NASA Johnson Space Center,...
Exposure to high doses of ionizing radiation produces both acute and late effects on the collagenized tissues and have profound effects on wound healing. Because of the crucial practical importance for new radioprotective agents, our study has been focused on evaluation of the efficacy of non-toxic naturally occurring compounds to protect tissue integrity against high-dose gamma radiation. Here, we demonstrate that molecular integrity of collagen may serve as a sensitive biological marker for...
Topics: Clearant, Inc., Griko, Y. V., NASA Ames Research Center, Yan, Xiaoli
This report is intended to provide a broad knowledge of various topics associated with NASA's Aeronautics Research Mission Directorate (ARMD), with particular interest on the NASA SBIR contracts awarded from 2011-2012 executed by small companies. The content of this report focuses on the high-quality, cutting-edge research that will lead to revolutionary concepts, technologies, and capabilities that enable radical change to both the airspace system and the aircraft that fly within it,...
Topics: ATA Engineering, Inc., Corke, Thomas C., Creare, Inc., Davis, Joshua T., Dimension Technologies,...
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This disclosure provides water processing apparatuses, systems, and methods for recovering water from wastewater such as urine. The water processing apparatuses, systems, and methods can utilize membrane technology for extracting purified water in a single step. A containment unit can include an ionomer membrane, such as Nafion(TradeMark) over a hydrophobic microporous membrane, such as polytetrafluoroethylene (PTFE). The containment unit can be filled with wastewater, and the hydrophobic...
Topics: Kelsey, Laura, MacCallum, Taber K., c1bb252a2fa547f99da535a93923b31e,...
We propose a method for TMR insertion verification that satisfies the process for reliable and trusted systems. If a system is expected to be protected using TMR, improper insertion can jeopardize the reliability and security of the system. Due to the complexity of the verification process, there are currently no available techniques that can provide complete and reliable confirmation of TMR insertion. This manuscript addresses the challenge of confirming that TMR has been inserted without...
Topics: ASRC Federal Space and Defense, Berg, Melanie, LaBel, Kenneth A., NASA Goddard Space Flight Center
The effects of fuselage cross sections and structural members on the performance of hypersonic cruise aircraft are evaluated. Representative fuselage/tank area structure was analyzed for strength, stability, fatigue and fracture mechanics. Various thermodynamic and structural tradeoffs were conducted to refine the conceptual designs with the primary objective of minimizing weight and maximizing aircraft range.
Topics: NASA Technical Reports Server (NTRS), AIRCRAFT DESIGN, HYPERSONIC VEHICLES, TANK GEOMETRY, COOLING,...
High-energy X-ray spectra of the Crab Nebula, Cyg- XR-1, and Cen A were determined from observations with the scintillation spectrometer on board the OSO-8 satellite, launched in June, 1975. Each of these sources was observed over two periods of 8 days or more, enabling a search for day-to-day and year to year variations in the spectral and temporal characteristics of the X-ray emission. No variation in the light curve of the Crab pulsar was found from observations which span a 15-day period in...
Topics: NASA Technical Reports Server (NTRS), NEUTRON SPECTROMETERS, OSO-8, SCINTILLATION COUNTERS, X RAY...
The author has identified the following significant results. Studies of cover distribution along Delaware's coast, especially in tidal wetlands, were made utilizing semi-automated analysis of LANDSAT-1 MSS digital data. Cover maps with eleven vegetation and other cover categories were produced with accuracy of identification above 80% in all categories. Recent studies have tested a new technique for training automated analysis which uses ground measured reflectance and atmospheric correction...
Topics: NASA Technical Reports Server (NTRS), COASTS, CROP IDENTIFICATION, DELAWARE, REFLECTANCE,...
This report gives the results of tests on a rectangular wing model with a 20% full spun split flap, conducted on the whirling arm at the Daniel Guggenheim Airship Institute in Akron, Ohio. The effect of a ground board on the lift and pitching moment was measured. The ground board consisted of an inclined ramp rising up in the test channel to a level floor extending for some distance parallel to the model path. The path of the wing model with respect to the ground board accordingly represented...
Topics: Akron Univ., Long, M. E.
Topic: NASA Technical Reports Server (NTRS)
The development of new cowlings, applicable to a short-nose radial engine, is described. These cowlings, designated the NACA cowlings D(sub s) and D(sub sf), employ a larger spinner and a higher inlet-velocity ratio than does the conventional NACA cowling C. The pressures available for cooling and the estimated critical Mach number were found to be higher with the new cowlings than are usually encountered with the conventional NACA cowling C. Large-chord propeller cuffs were found to have a...
Topics: National Advisory Committee for Aeronautics. Langley Aeronautical Lab., Valentine, E. Floyd
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Individual frames on a photographic film strip in a projector are automatically positioned by a simple circuit. The circuit uses a photodiode that senses frame registry position and a relay that stops the film-advance motor to suspend the film at point of registry.
Topic: NASA Technical Reports Server (NTRS)