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The Vehicle Integrated Thermal Management Analysis Code (VITMAC) was further developed to aid the analysis, design, and optimization of propellant and thermal management concepts for advanced propulsion systems. The computational tool is based on engineering level principles and models. A graphical user interface (GUI) provides a simple and straightforward method to assess and evaluate multiple concepts before undertaking more rigorous analysis of candidate systems. The tool incorporates the...
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Topics: NASA Technical Reports Server (NTRS), AEROTHERMODYNAMICS, ROCKET-BASED COMBINED-CYCLE ENGINES,...
NASA Network Resource and Training Site
Dec 22, 2021 NASA Technical Reports Server (NTRS)
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No abstract available
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Topics: Jarvis, Sarah, Kim, Han, Leidos, Inc., MEI Technologies, Inc., NASA Johnson Space Center, Young,...
NASA Network Resource and Training Site
Jul 7, 2019 NASA Technical Reports Server (NTRS)
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Coronal mass ejections (CMEs) and high-speed solar wind streams (HSS) are two solar phenomena that produce large-scale structures in the interplanetary (IP) medium. CMEs evolve into interplanetary CMEs (ICMEs) and the HSS result in corotating interaction regions (CIRs) when they interact with preceding slow solar wind. CMEs and CIRs originate from closed (active region and filament region) and open (corona) hole) magnetic field regions on the Sun, respectively. These two types of mass emissions...
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Topics: NASA Technical Reports Server (NTRS), CORONAL MASS EJECTION, ENVIRONMENT EFFECTS, SOLAR ACTIVITY,...
NASA Network Resource and Training Site
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NASA's In-Space Propulsion Technology Program is investing in technologies that have the potential to revolutionize the robotic exploration of deep space. For robotic exploration and science missions, increased efficiencies of future propulsion systems are critical to reduce overall life-cycle costs and, in some cases, enable missions previously considered impossible. Continued reliance on conventional chemical propulsion alone will not enable the robust exploration of deep space - the maximum...
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Topics: NASA Technical Reports Server (NTRS), SPACECRAFT PROPULSION, TECHNOLOGY ASSESSMENT, NASA PROGRAMS,...
Studies over the last decade have shown radioisotope-based nuclear electric propulsion to be enhancing and, in some cases, enabling for many potential robotic science missions. Also known as radioisotope electric propulsion (REP), the technology offers the performance advantages of traditional reactor-powered electric propulsion (i.e., high specific impulse propulsion at large distances from the Sun), but with much smaller, affordable spacecraft. Future use of REP requires development of...
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Topics: NASA Technical Reports Server (NTRS), NUCLEAR ELECTRIC PROPULSION, HALL THRUSTERS, ION ENGINES,...
Ring current effect on boundary of geomagnetic field in solar wind
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Topic: NASA Technical Reports Server (NTRS)
NASA Network Resource and Training Site
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Bibliography of aeronautical engineering with abstracts
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Topic: NASA Technical Reports Server (NTRS)
This bibliography lists 295 reports, articles, and other documents introduced into the NASA Scientific and Technical Information System in August 1978.
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Topics: NASA Technical Reports Server (NTRS), AERODYNAMICS, AERONAUTICAL ENGINEERING, AERONAUTICS, AIRCRAFT...
NASA Network Resource and Training Site
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This Program User's Guide discusses the Nuclear Thermal Propulsion (NTP) engine system design features and capabilities modeled in the Nuclear Engine System Simulation (NESS): Version 2.0 program (referred to as NESS throughout the remainder of this document), as well as its operation. NESS was upgraded to include many new modeling capabilities not available in the original version delivered to NASA LeRC in Dec. 1991, NESS's new features include the following: (1) an improved input format; (2)...
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Topics: NASA Technical Reports Server (NTRS), COMPUTERIZED SIMULATION, NUCLEAR ENGINE FOR ROCKET VEHICLES,...
Studies were conducted to develop appropriate space shuttle electrical power distribution and control (EPDC) subsystem simulation models and to apply the computer simulations to systems analysis of the EPDC. A previously developed software program (SYSTID) was adapted for this purpose. The following objectives were attained: (1) significant enhancement of the SYSTID time domain simulation software, (2) generation of functionally useful shuttle EPDC element models, and (3) illustrative...
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Topics: NASA Technical Reports Server (NTRS), COMPUTERIZED SIMULATION, ELECTRIC EQUIPMENT, ELECTRIC POWER...
A narrow-beam (1 degree beamwidth), multi-channel (20 to 30 and 89 GHz), polarized (89 vertical and horizontal) radiometer with full azimuth and elevation scanning capabilities has been built with the purpose of improving the detection of in-flight icing hazards to aircraft in the near airport environment. This goal was achieved by co-locating the radiometer with Colorado State University's CHILL polarized Doppler radar and taking advantage of similar beamwidth and volume scan regiments. In...
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Topics: NASA Technical Reports Server (NTRS), AIRCRAFT ICING, DOPPLER RADAR, RADIOMETERS, AVIATION...
NASA Network Resource and Training Site
Dec 3, 2016 NASA Technical Reports Server (NTRS)
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Linea Research Corporation has developed a wearable noninvasive monitor that provides continuous blood pressure and heart rate measurements in extreme environments. Designed to monitor the physiological effects of astronauts' prolonged exposure to reduced-gravity environments as well as the effectiveness of various countermeasures, the device offers wireless connectivity to allow transfer of both real-time and historical data. It can be modified to monitor the health status of astronaut crew...
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Topics: NASA Technical Reports Server (NTRS), BLOOD PRESSURE, PRESSURE MEASUREMENT, HEART RATE, MONITORS,...
The Space Power Architecture Study (SPAS) identified and evaluated power subsystem options for multimegawatt electric (MMWE) space based weapons and surveillance platforms for the Strategic Defense Initiative (SDI) applications. Steady state requirements of less than 1 MMWE are adequately covered by the SP-100 nuclear space power program and hence were not addressed in the SPAS. Four steady state power systems less than 1 MMWE were investigated with little difference between them on a mass...
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Topics: NASA Technical Reports Server (NTRS), HYDROGEN OXYGEN FUEL CELLS, SPACE POWER REACTORS, SPACECRAFT...
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A method of designing a self-adaptive missile guidance system is presented. The system inputs are assumed to be known in a statistical sense only. Newton's modified Wiener theory is utilized in the design of the system and to establish the performance criterion. The missile is assumed to be a beam rider, to have a g limiter, and to operate over a flight envelope where the open-loop gain varies by a factor of 20. It is shown that the percent of time that missile acceleration limiting occurs can...
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Topic: NASA Technical Reports Server (NTRS)
NASA Network Resource and Training Site
Aug 7, 2016 NASA Technical Reports Server (NTRS)
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The crisis which troubles the world market for liquid fuel in general and for carburants in particular is doubtless one of the most serious ever experienced by modern industry. It is a national crisis of economic and political independence for countries like Italy and France. The solutions suggested for meeting the lack of liquid fuel may be summed up under two general headings: the economical use of the petroleum now available; creation of petroleum substitutes from natural sources within the...
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Topic: NASA Technical Reports Server (NTRS)
NASA Network Resource and Training Site
Aug 5, 2016 NASA Technical Reports Server (NTRS)
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This compilation of the outstanding characteristics of the available aircraft engines of the world was prepared as a compact ready reference for desk use. It does not pretend to be anything but a skeleton outline of the characteristics of engines reported in the technical press as being in either the experimental, development, or production stage.
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Topic: NASA Technical Reports Server (NTRS)
A program was undertaken to develop an iron-base alloy having a fracture toughness of 220 MPa. m superscript 1/2 with a corresponding yield stress of 1.4 GPa (200 ksi) at-196 C. An Fe-12Ni alloy was selected as the base alloy. Factors considered included reactive metal additions, effects of interstitial impurities, strengthening mechanisms, and weldability. The goals were met in an Fe-12Ni-0.5Al alloy strengthened by thermomechanical processing or by precipitate strengthening with 2 percent Cu....
Topics: NASA Technical Reports Server (NTRS), CRYOGENICS, FRACTURE STRENGTH, IRON ALLOYS, NICKEL ALLOYS,...
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Under the NASA-KAIA-KARI ATM research collaboration agreement, SOSS ICN Model has been developed for Incheon International Airport. This presentation describes the model validation work in the project. The presentation will show the results and analysis of the validation.\n\n\n\n\n\n
Topics: SGT, Inc., Zhu, Zhifan
The Station Explorer for X-ray Timing and Navigation Technology (SEXTANT) is a technology demonstration enhancement to the Neutron-star Interior Composition Explorer (NICER) mission. NICER is a NASA Explorer Mission of Opportunity that will be hosted on the International Space Station (ISS). SEXTANT will, for the first time, demonstrate real-time, on-board X-ray Pulsar Navigation (XNAV), a significant milestone in the quest to establish a GPS-like navigation capability available throughout our...
Topics: Arzoumanian, Zaven, Gendreau, Keith C., Hassouneh, Munther A., Mitchell, Jason W., NASA Goddard...
No abstract available
Topics: Mears, Teri, NASA Marshall Space Flight Center
No abstract available
Topics: Arnold, B., Chao, Fow-Sen, Kelly, Lisa, Maryland Univ. Baltimore County, NASA Marshall Space Flight...
When optimizing the performance of complex systems, a logical area for concern is improving the efficiency of useful energy. The energy available for a system to perform work is defined as a system's energy content. Interactions between a system's subsystems and the surrounding environment can be accounted for by understanding various subsystem energy efficiencies. Energy balance of reactants and products, and enthalpies and entropies, can be used to represent a chemical process. Heat transfer...
Topics: Alabama Univ., Clem, Kirk A., Mesmer, Bryan L., NASA Marshall Space Flight Center, Nelson, George...
GEMS and ultrafine grained polyphase units (UFG-PU) in anhydrous IDPs are probably some of the most primitive materials in the solar system. UFG-PUs contain nanocrystalline silicates, oxides, metals and sulfides. GEMS are rounded approximately 100 nm across amorphous silicates containing embedded iron-nickel metal grains and sulfides. GEMS are one of the most abundant constituents in some anhydrous CPIDPs, often accounting for half the material or more. When NASA's Stardust mission returned...
Topics: American Museum of Natural History, Bechtel, H. A., Brownlee, D. E., Butterworth, A. L., California...
Supported dual-mode burst diaphragm protects vacuum vessels from transient internal pressures. It forms the interface between the vacuum in the vessel and an external pressure.
Topic: NASA Technical Reports Server (NTRS)
Testing device stretches elastic materials biaxially over large deformation ranges and varies strain ratios in two perpendicular directions. The device is used in conjunction with a tensile testing machine, which holds the specimen and permits control over the direction and magnitude of the stresses applied.
Topic: NASA Technical Reports Server (NTRS)
Linear theory is used, without two dimensional or slender body assumptions, to predict flow field produced by aircraft wing, nose, inlet, and pylons. Aircraft shock wave locations are predicted, and their effect on flow field is included through transformation of aircraft geometry. Program was written in FORTRAN IV for CDC 6400 computer.
Topics: NASA Technical Reports Server (NTRS), CDC 6000 SERIES COMPUTERS, COMPUTER PROGRAMS, FLOW...
The research included ongoing development of methodology that provides probabilistic lifetime strength of aerospace materials via computational simulation. A probabilistic material strength degradation model, in the form of a randomized multifactor interaction equation, is postulated for strength degradation of structural components of aerospace propulsion systems subjected to a number of effects or primative variables. These primative variable may include high temperature, fatigue or creep. In...
Topics: NASA Technical Reports Server (NTRS), AIRCRAFT CONSTRUCTION MATERIALS, COMPUTER PROGRAMS,...
One of the critical datasets for optimal selection of future lunar landing sites is local- to regional-scale topography. Lunar base site selection will require such data for both engineering and scientific operations purposes. The Lunar Geoscience Orbiter or Lunar Observer is the ideal precursory science mission from which to obtain this required information. We suggest that a simple laser altimeter instrument could be employed to measure local-scale slopes, heights, and depths of lunar surface...
Topics: NASA Technical Reports Server (NTRS), LASER ALTIMETERS, LUNAR BASES, LUNAR LANDING SITES, LUNAR...
The field of human factors is as varied and diverse as the human subject itself. But one of its most important applications is the facilitation of safety and efficiency in a particular working environment through the implementation of paradigms known about humans and their working relationship with machines and systems. During the period since World War II (which is often viewed as the birth of Human Factors) no area has been the subject of more human factors research than aviation. And in no...
Topics: NASA Technical Reports Server (NTRS), AIRCRAFT SAFETY, CERTIFICATION, COMPLEX SYSTEMS, FLIGHT...
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The invention is a multiple interconnected network of intelligent message-repeating remote nodes which employs an antibody recognition message termination process performed by all remote nodes and a remote node polling process performed by other nodes which are master units controlling remote nodes in respective zones of the network assigned to respective master nodes. Each remote node repeats only those messages originated in the local zone, to provide isolation among the master nodes.
Topics: NASA Technical Reports Server (NTRS), ANTIBODIES, PROTOCOL (COMPUTERS), REPETITION, PATENTS,...
In 1986, RAID (redundant array of inexpensive (or independent) disks) technology was introduced as a viable solution to the I/O bottleneck. A number of different RAID levels were defined in 1987 by the Computer Science Division (EECS) University of California, Berkeley, each with specific advantages and disadvantages. With multiple RAID options available, taking advantage of RAID technology required matching particular RAID levels with specific applications. It was not possible to use one RAID...
Topics: NASA Technical Reports Server (NTRS), COMPUTER STORAGE DEVICES, DATA RETRIEVAL, DATA STORAGE, DATA...
Attitude estimator use observations from different times to reduce the effects of noise. If the vehicle is rotating, the attitude at one time needs to be propagated to that at another time. If the vehicle measures its angular velocity, attitude propagating entails integrating a rotational kinematics equation only. If a measured angular velocity is not available, torques can be computed and an additional rotational dynamics equation integrated to give the angular velocity. Initial conditions for...
Topics: NASA Technical Reports Server (NTRS), ANGULAR VELOCITY, DYNAMIC MODELS, SATELLITE ORIENTATION,...
Practitioners of climate change prediction base many of their future climate scenarios on General Circulation Models (GCM's), each model with differing assumptions and parameter requirements. For representing the atmosphere, GCM's typically contain equations for calculating motion of particles, thermodynamics and radiation, and continuity of water vapor. Hydrology and heat balance are usually included for continents, and sea ice and heat balance are included for oceans. The current issue of...
Topics: NASA Technical Reports Server (NTRS), ATMOSPHERIC GENERAL CIRCULATION MODELS, CLIMATE MODELS,...
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Investigations leading to a specification for aviation turbine fuel produced from whole crude shale oil are described. Refining methods involving hydrocracking, hydrotreating, and extraction processes are briefly examined and their production capabilities are assessed.
Topics: NASA Technical Reports Server (NTRS), AIRCRAFT FUELS, FUEL PRODUCTION, JET ENGINE FUELS, SHALE OIL,...
Design and process development tasks intended to demonstrate composite blade application in large high by-pass ratio turbofan engines are described. Studies on a 3.0 aspect radio space and shell construction fan blade indicate a potential weight savings for a first stage fan rotor of 39% when a hollow titanium spar is employed. An alternate design which featured substantial blade internal volume filled with titanium honeycomb inserts achieved a 14% potential weight savings over the B/M rotor...
Topics: NASA Technical Reports Server (NTRS), AIRFOILS, ALUMINUM ALLOYS, BORON REINFORCED MATERIALS,...
Most investigators ascribe mare basalt magma genesis to partial melting at depths of approximately 130 to greater than 400 km within the cumulate pile deposited from a lunar magma ocean. Mare basalts share with mid-ocean ridge basalts the characteristic of relative depletion in LREE and other incompatible trace elements that arises from melting within 'used' mantle, from which crust-forming elements have already been separated. Some mare basalt types do not show the classical, La-Nd depleted...
Topics: NASA Technical Reports Server (NTRS), ASCENT, ASSIMILATION, BASALT, CONES (VOLCANOES), EARTH CRUST,...
Maximum possible error in position in least squares elliptical orbit
Topic: NASA Technical Reports Server (NTRS)
A comparison of three square root filter formulations with the standard extended Kalman filter is described. The characteristics of the algorithms were compared by simulating the application of a phase one GPS system to the determination of a LANDSAT-D Satellite.
Topics: NASA Technical Reports Server (NTRS), ALGORITHMS, DIGITAL FILTERS, SATELLITE NAVIGATION SYSTEMS,...
The key objectives of the NASA ASP are to: Improve mobility, capacity efficiency and access of the airspace system. Improve collaboration, predictability, and flexibility for the airspace users. Enable accurate modeling and simulation of air transportation systems. Accommodate operations of all classes of aircraft. Maintain system safety and environmental protection. In support of these program objectives, the major goal of the NextGen-SAIE Project is to enable the transition of key capacity...
Topics: NASA Technical Reports Server (NTRS), AIRSPACE, AIR TRANSPORTATION, ENVIRONMENT PROTECTION,...
In the next decade, gravitational wave instruments in space may provide high-precision measurements of gravitational-wave signals from strong sources, such as black holes. Currently variations on the original Laser Interferometer Space Antenna mission concepts are under study in the hope of reducing costs. Even the observations of a reduced instrument may place strong demands on numerical relativity capabilities. Possible advances in the coming years may fuel a new generation of codes ready to...
Topics: NASA Technical Reports Server (NTRS), BLACK HOLES (ASTRONOMY), GRAVITATIONAL WAVES, RELATIVITY,...
No abstract available
Topics: Burnside, C. G., NASA Marshall Space Flight Center, Pedersen, K. W., Pierce, C. W.
NASA utilizes an evidence based system to perform risk assessments for the human system for spaceflight missions. The center of this process is the multi-disciplinary Human System Risk Board (HSRB). The HSRB is chartered from the Chief Health and Medical Officer (OCHMO) at NASA Headquarters. The HSRB reviews all human system risks via an established comprehensive risk and configuration management plan based on a project management approach. The HSRB facilitates the integration of human research...
Topics: Francisco, D., NASA Johnson Space Center, Romero, E., Wyle Science, Technology and Engineering Group
ZnBeO and ZnCdSeO alloys have been disclosed as materials for the improvement in performance, function, and capability of semiconductor devices. The alloys can be used alone or in combination to form active photonic layers that can emit over a range of wavelength values. Materials with both larger and smaller band gaps would allow for the fabrication of semiconductor heterostructures that have increased function in the ultraviolet (UV) region of the spectrum. ZnO is a wide band-gap material...
Topics: NASA Technical Reports Server (NTRS), ZINC ALLOYS, SEMICONDUCTOR DEVICES, FABRICATION, P-I-N...
Land surface modeling and data assimilation can provide dynamic land surface state variables necessary to support physical precipitation retrieval algorithms over land. It is well-known that surface emission, particularly over the range of frequencies to be included in the Global Precipitation Measurement Mission (GPM), is sensitive to land surface states, including soil properties, vegetation type and greenness, soil moisture, surface temperature, and snow cover, density, and grain size. In...
Topics: NASA Technical Reports Server (NTRS), PRECIPITATION MEASUREMENT, HYDROLOGY, SURFACE PROPERTIES,...
This presentation discusses use of 4 kilometer satellite-based sea surface temperature (SST) data to monitor and assess coral reef areas of the Florida Keys. There are growing concerns about the impacts of climate change on coral reef systems throughout the world. Satellite remote sensing technology is being used for monitoring coral reef areas with the goal of understanding the climatic and oceanic changes that can lead to coral bleaching events. Elevated SST is a well-documented cause of...
Topics: NASA Technical Reports Server (NTRS), CLIMATE CHANGE, CORAL REEFS, REMOTE SENSING, SEA SURFACE...
Presentation for FAA sponsored meeting to discuss time-based metering trial planning. This presentation describes the Dynamic Routes for Arrivals in Weather (DRAW) concept and the associated trial planning functionality.
Topics: Gong, Chester, NASA Ames Research Center
This paper explores the differences between, and shares the lessons learned from, two hypervelocity impact experiments critical to the update of orbital debris environment models. The procedures and processes of the fourth Satellite Orbital Debris Characterization Impact Test (SOCIT) were analyzed and related to the ongoing DebriSat experiment. SOCIT was the first hypervelocity impact test designed specifically for satellites in Low Earth Orbit (LEO). It targeted a 1960's U.S. Navy satellite,...
Topics: Aerospace Corp., Air Force Systems Command, Ausay, Erick, Blake, Brandon, Boyle, Colleen, Cornejo,...
The Communications and Intelligent Systems Division provides expertise, plans, conducts and directs research and engineering development in the competency fields of advanced communications and intelligent systems technologies for application in current and future aeronautics and space systems.
Topics: Miranda, Felix A., NASA Glenn Research Center
A flight simulation study was conducted at NASA Langley Research Center to evaluate flight deck systems that (1) predict aircraft energy state and/or autoflight configuration, (2) present the current state and expected future state of automated systems, and/or (3) show the state of flight-critical data systems in use by automated systems and primary flight instruments. Four new technology concepts were evaluated vis-à-vis current state-of-the-art flight deck systems and indicators. This...
Topics: Daniels, Taumi, Etherington, Tim, Evans, Emory, NASA Langley Research Center, Rockwell Collins,...
The feasibility of remotely piloted aircraft performing year around missions at an altitude of 70,000 feet is determined. Blimp and airplane type vehicles employing solar-voltaic, microwave, or nuclear propulsion systems were considered. A payload weighing 100 pounds and requiring 1000 watts of continuous power was assumed for analysis purposes. Results indicate that a solar powered aircraft requires more solar cell area than is available on conventional aircraft configurations if designed for...
Topics: NASA Technical Reports Server (NTRS), AIRCRAFT FUELS, AIRSHIPS, MICROWAVE TRANSMISSION, NUCLEAR...
Rigorous analytical technique, called criticality determination methodology /or CD technique/ determines the probability that a given complex system will successfully achieve stated objectives. The CD technique identifies critical elements of the system by a failure mode and effects analysis.
Topic: NASA Technical Reports Server (NTRS)
A numerical simulation of the final stages of transition to turbulence in plane channel flow at a Reynolds number of 7500 is described. Three dimensional, incompressible Navier-Stokes equations are numerically integrated to obtain the time evolution of two and three dimensional finite amplitude disturbances. Computations are performed on the CYBER-203 vector processor for a 32 by 33 by 32 grid. Solutions indicate the existence of structures similar to those observed in the laboratory and which...
Topics: NASA Technical Reports Server (NTRS), CHANNEL FLOW, FLOW DISTRIBUTION, NUMERICAL FLOW...
This databank is the collation of radiation test data submitted by many testers and serves as a reference for engineers who are concerned with and have some knowledge of the effects of the natural radiation environment on microcircuits. It contains radiation sensitivity results from ground tests and is divided into two sections. Section A lists total dose damage information, and section B lists single event upset cross sections, I.E., the probability of a soft error (bit flip) or of a hard...
Topics: NASA Technical Reports Server (NTRS), LATCH-UP, MICROELECTRONICS, RADIATION DAMAGE, RADIATION...
Computer implemented phase-slope and cross-correlation methods are introduced for measuring time delays between pairs of broadband ultrasonic pulse-echo signals for determining velocity in engineering materials. The phase-slope and cross-correlation methods are compared with the overlap method which is currently in wide use. Comparison of digital versions of the three methods shows similar results for most materials having low ultrasonic attenuation. However, the cross-correlation method is...
Topics: NASA Technical Reports Server (NTRS), CROSS CORRELATION, NONDESTRUCTIVE TESTS, SOLIDS, ULTRASONICS,...
An initial modification to the MSF/J70 Thermospheric Model, in which the variations due to sudden geomagnetic disturbances upon the Earth's upper atmospheric density structure were modeled is presented. This dynamic model of the geomagnetic variation included is an improved version of one which SAO developed from the analysis of the ESRO 4 mass spectrometer data that was incorporated in the Jacchia 1977 model. The variation with geomagnetic local time as well as with geomagnetic latitude are...
Topics: NASA Technical Reports Server (NTRS), ATMOSPHERIC MODELS, EARTH (PLANET), MAGNETIC ANOMALIES,...
The development and use of NASA's Pilot Climate Data System (PCDS) are discussed. The PCDS is used as a focal point for managing and providing access to a large collection of actively used data for the Earth, ocean and atmospheric sciences. The PCDS provides uniform data catalogs, inventories, and access methods for selected NASA and non-NASA data sets. Scientific users can preview the data sets using graphical and statistical methods. The system has evolved from its original purpose as a...
Topics: NASA Technical Reports Server (NTRS), ATMOSPHERIC PHYSICS, DATA BASE MANAGEMENT SYSTEMS, DATA...
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The building in the top photo is the new home of the National Permanent Savings Bank in Washington, D.C., designed by Hartman-Cox Architects. Its construction was based on a money-saving method of preparing building specifications which derived from NASA technology developed to obtain quality construction while holding down cost of launch facilities, test centers and other structures. Written technical specifications spell out materials and components to be used on construction projects and...
Topics: NASA Technical Reports Server (NTRS), BUILDINGS, SPECIFICATIONS, COMPUTER NETWORKS, CONSTRUCTION,...
Primitive carbonaceous chondrites contain a wide variety of organic material, ranging from soluble discrete molecules to insoluble unstructured kerogen-like component as well as structured nano-globules of macromolecular carbon. The relationship between the soluble organic molecules, macromolecular organic material, and host minerals are poorly understood. Due to the differences in extractability of soluble and insoluble organic materials, the analysis methods for each differ and are often...
Topics: Berger, E. L., Burton, A. S., California Univ., Cao, T., Clemett, S. J., ERC International, Inc.,...
The Orion Multi-Purpose Crew Vehicle (MPCV) is an American spacecraft for carrying four astronauts during deep space missions. This paper describes an innovative application of Power Injection Method (PIM) for allocating Orion cabin continuous noise Sound Pressure Level (SPL) limits to the sound power level (PWL) limits of major noise sources in the Environmental Control and Life Support System (ECLSS) during all mission phases. PIM is simulated using both Statistical Energy Analysis (SEA) and...
Topics: Allen, Christopher S., Chu, S. Reynold, Dandaroy, Indranil, Lockheed Martin Corp., NASA Johnson...
Several techniques were employed to apply or otherwise form porous layers of various materials on the surface of hot-pressed silicon carbide ceramic. From mechanical properties measurements and studies, it was concluded that although porous layers could be applied to the silicon carbide ceramic, sufficient damage was done to the silicon carbide surface by the processing required so as to drastically reduce its mechanical strength. It was further concluded that there was little promise of...
Topics: NASA Technical Reports Server (NTRS), CERAMICS, IMPACT STRENGTH, SILICON CARBIDES, ENERGY...
The low gravity environment of earth orbit offers the potential for performing experiments involving baroclinic Geophysical Fluid Dynamics (GFD) on spherical surfaces. These experiments in turn have the potential for providing deeper understanding of large scale planetary and solar circulations. However, to perform these experiments, one requires an experimental technique whereby a radially directed body force can be generated to simulate a radial gravitational force field. One viable technique...
Topics: NASA Technical Reports Server (NTRS), EARTH ATMOSPHERE, ENVIRONMENT SIMULATION, BAROCLINITY, FLUID...
The effect of varying the two important display parameters of a pictorial display on pilot opinion performance, and pilot aircraft display system servomechanism response is examined. The display presents a picture of a three dimensional box that moves along the desired path ahead of the aircraft. The two display parameters examined are the field of view of the picture (from + or - 5 deg to + or - 45 deg) and the distance to the box (from 92 m (300 ft) to 6100 m (20 000 ft)). The results show...
Topics: NASA Technical Reports Server (NTRS), AIRCRAFT INSTRUMENTS, DISPLAY DEVICES, SERVOMECHANISMS, ERROR...
Several advanced atmospheric remote sensing systems developed at the Jet Propulsion Laboratory were demonstrated under various field conditions to determine how useful they would be for general use by the California Air Resources Board and local air quality districts. One of the instruments reported on is the Laser Absorption Spectrometer (LAS). It has a pair of carbon dioxide lasers with a transmitter and receiver and can be flown in an aircraft to measure the column abundance of such gases as...
Topics: NASA Technical Reports Server (NTRS), MOISTURE CONTENT, OZONE, WATER VAPOR, ABSORPTION SPECTRA, AIR...
Recent observations using the Hubble Space Telescope of the z = 0.156 QSO 3C 273 have discovered a surprisingly large number of Ly-alpha absorption lines. In particular, Morris et al. found 9 certain and 7 possible Ly-alpha lines with equivalent widths above 25 mA. This is much larger (by a factor of 5-10) than the number expected from extrapolation of the high-redshift behavior of the Ly-alpha forest. Within the context of pressure-confined models for the Ly-alpha clouds, this behavior can be...
Topics: NASA Technical Reports Server (NTRS), DARK MATTER, DISK GALAXIES, GALACTIC HALOS, LYMAN SPECTRA,...
Calibrating an ultrasonic transducer can be performed with a reduced number of calculations and testing. A wide-band pulser is connected to an ultrasonic transducer under test to generate ultrasonic waves in a liquid. A single frequency is transmitted to the electrostatic acoustic transducer (ESAT) and the voltage change produced is monitored. Then a broadband ultrasonic pulse is generated by the ultrasonic transducer and received by the ESAT. The output of the ESAT is amplified and input to a...
Topics: NASA Technical Reports Server (NTRS), BROADBAND, CALIBRATING, ELECTROACOUSTIC TRANSDUCERS,...
In recent years a variety of space-activity schedulers have been developed within the aerospace community. Space-activity schedulers are characterized by their need to handle large numbers of activities which are time-window constrained and make high demands on many scarce resources, but are minimally constrained by predecessor/successor requirements or critical paths. Two needs to exchange data between these schedulers have materialized. First, there is significant interest in comparing and...
Topics: NASA Technical Reports Server (NTRS), AEROSPACE INDUSTRY, CRITICAL PATH METHOD, INTERNATIONAL SPACE...
One of the clear benefits of conducting scientific research in space is to take advantage of the reduced acceleration environment. Many accelerometer packages have proven to accurately measure the acceleration environment at frequency levels above one Hz. However, for particular classes of experiments the quality of science returns is a direct function of the extremely low frequency (less than 0.01 Hz), quasi-steady acceleration environment. One class particularly interested in this...
Topics: NASA Technical Reports Server (NTRS), CRYSTAL GROWTH, ACCELEROMETERS, ACCELERATION (PHYSICS), REAL...
An extensive wind tunnel test campaign was undertaken to quantify the performance and acoustics of a counter-rotating open rotor system. The present document summarizes the portion of this test performed with the so-called \"Historical Baseline\" rotor blades, designated F31/A31. It includes performance and acoustic data acquired at Mach numbers from take-off to cruise. It also includes the effect of propulsor angle of attack as well as an upstream pylon. This report is accompanied by...
Topics: NASA Glenn Research Center, Stephens, David B.
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An overview of the observations of TGFs by BATSE during the nine-year mission of the Compton Gamma-ray Observatory will be presented.
Topics: NASA Technical Reports Server (NTRS), GAMMA RAY OBSERVATORY, GAMMA RAY BURSTS, GAMMA RAYS,...
Knowledge of the gravitation field, in combination with surface topography, provides one of the principal means of inferring the internal structure of a planetary body. Previous analyses of the lunar gravitational field have been based on data from the Lunar Orbiters, the Apollo subsatellites, and the low altitude passes of the Apollo spacecraft. Recently, Konopliv et al. have reanalyzed all available Lunar Orbiter and Apollo subsatellite tracking data, producing a 60th degree and order...
Topics: NASA Technical Reports Server (NTRS), GRAVITATION, GRAVITATIONAL FIELDS, LUNAR GRAVITATION, LUNAR...
The abundance and distribution of H2O within the terrestrial planets, as well as its timing of delivery, is a topic of vital importance for understanding the chemical and physical evolution of planets and their potential for hosting habitable environments. Analysis of planetary materials from Mars, the Moon, and the eucrite parent body (i.e., asteroid 4Vesta) have confirmed the presence of H2O within their interiors. Moreover, H and N isotopic data from these planetary materials suggests H2O...
Topics: Boyce, Jeremy W., California Univ., Carnegie Institution of Washington, Elardo, Stephen M.,...
Topic: NASA Technical Reports Server (NTRS)
Topic: NASA Technical Reports Server (NTRS)
The Mars robotic sample return mission has been a potential flagship mission for NASA s science mission directorate for decades. The Mars Exploration Program and the planetary science decadal survey have highlighted both the science return of the Mars Sample Return mission, but also the need for risk reduction through technology development. One of the critical elements of the MSR mission is the Mars Ascent Vehicle, which must launch the sample from the surface of Mars and place it into low...
Topics: NASA Technical Reports Server (NTRS), MARS SAMPLE RETURN MISSIONS, LAUNCH VEHICLES, MARS...
Abstracts are presented of research conducted on source encoding for two-dimensional data.
Topics: NASA Technical Reports Server (NTRS), ABSTRACTS, CODING, DATA PROCESSING, ERRORS, INFORMATION...