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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 397 records · Page 22
All sourcesNASA NTRSDOE OSTI
NASA NTRS1985

A Brief Description of the Two Primate Experiments to Be Carried Out on SL-4

Two primate experiments to be carried on Spacelab 4 are discussed. One of these investigates thermoregulation of primates during altered gravity. In previous ground-based tests, primate heat distribution was shown to change during centrifugation (a way of subjecting subjects to higher-than-Earth gravity), the inner body cooling off and the skin temperature rising. The adaptive and homeostatic mechanisms triggered by spaceflight are studied. Ways in which to correct any undesirable shifts in the homeostatic capabilities of the thermoregulatory control system are addressed. The other experiment involving primates addressess the changes in fluid distribution and electrolyte content of blood that occur in spaceflight. During previous space missions, fluid shifts from the legs to the chest and head have been noted. Ground-based studies have shown decreases in blood potassium levels and increases in potassium excretion.

Elsea, L.↗
NASA NTRS1980

Smoke and dust particles of meteoric origin in the mesosphere and stratosphere

A height profile of ablated mass from meteors is calculated, assuming an incoming mass of 10 to the -16th g/sq cm/s (44 metric tons per day) and the velocity distribution of Southworth and Sekanina, which has a mean of 14.5 km/s. The profile peaks at 84 km. The fluxes of micrometeorites and residual meteoroids are also calculated. The coagulation of the evaporated silicates into 'smoke' particles is then followed by means of a model adapted from a previous study of the stratospheric sulfate layer. Numerous sensitivity tests are made. Features of the results are a sharp cutoff of the particle distribution above 90 km, and a surface area close to 10 to the -9th sq cm/cu cm all the way from 30 to 85 km. Some confirmation is obtained from balloon studies of condensation nuclei, although the various measurements differ greatly. The optical scattering and extinction are shown to be undetectable. Several potential applications are suggested: nucleation of sulfate particles and noctilucent clouds, scavenging of metallic ions and atoms, and perhaps other aeronomical effects. The latter are limited to processes that can be influenced by a collision time of the order of a day.

Hunten, D. M.↗
NASA NTRS2004

The Development of Two Science Investigator-led Processing Systems (SIPS) for NASA's Earth Observation System (EOS)

In 2001, NASA Goddard Space Flight Center's Laboratory for Terrestrial Physics started the construction of a science Investigator-led Processing System (SIPS) for processing data from the Ozone Monitoring Instrument (OMI) which will launch on the Aura platform in mid 2004. The Ozone Monitoring Instrument (OMI) is a contribution of the Netherlands Agency for Aerospace Programs (NIVR) in collaboration with the Finnish Meteorological Institute (FMI) to the Earth Observing System (EOS) Aura mission. It will continue the Total Ozone Monitoring System (TOMS) record for total ozone and other atmospheric parameters related to ozone chemistry and climate. OMI measurements will be highly synergistic with the other instruments on the EOS Aura platform. The LTP previously developed the Moderate Resolution Imaging Spectrometer (MODIS) Data Processing System (MODAPS), which has been in full operations since the launches of the Terra and Aqua spacecrafts in December, 1999 and May, 2002 respectively. During that time, it has continually evolved to better support the needs of the MODIS team. We now run multiple instances of the system managing faster than real time reprocessings of the data as well as continuing forward processing. The new OMI Data Processing System (OMIDAPS) was adapted from the MODAPS. It will ingest raw data from the satellite ground station and process it to produce calibrated, geolocated higher level data products. These data products will be transmitted to the Goddard Distributed Active Archive Center (GDAAC) instance of the Earth Observing System (EOS) Data and Information System (EOSDIS) for long term archive and distribution to the public. The OMIDAPS will also provide data distribution to the OMI Science Team for quality assessment, algorithm improvement, calibration, etc. We have taken advantage of lessons learned from the MODIS experience and software already developed for MODIS. We made some changes in the hardware system organization, database and software to adapt the system for OMI. We replaced the fundamental database system, Sybase, with an Open Source RDBMS called PostgreSQL, and based the entire OMIDAPS on a cluster of Linux based commodity computers rather than the large SGI servers that MODAPS uses. Rather than relying on a central I/O server host, the new system distributes its data archive among multiple server hosts in the cluster. OMI is also customizing the graphical user interfaces and reporting structure to more closely meet the needs of the OMI Science Team. Prior to 2003, simulated OMI data and the science algorithms were not ready for production testing. We initially constructed a prototype system and tested using a 25 year dataset of Total Ozone Mapping Spectrometer (TOMS) and Solar Backscatter Ultraviolet Instrument (SBUV) data. This prototype system provided a platform to support the adaptation of the algorithms for OMI, and provided reprocessing of the historical data aiding in its analysis. In a recent reanalysis of the TOMS data, the OMIDAPS processed 108,000 full orbits of data through 4 processing steps per orbit, producing about 800,000 files (400 GiB) of level 2 and greater data files. More recently we have installed two instances of the OMIDAPS for integration and testing of OM1 science processes as they get delivered from the Science Team. A Test instance of the OMIDAPS has also supported a series of "Interface Confidence Tests" (ICTs) and End-to-End Ground System tests to ensure the launch readiness of the system. This paper will discuss the high-level hardware, software, and database organization of the OMIDAPS and how it builds on the MODAPS heritage system. It will also provide an overview of the testing and implementation of the production OMIDAPS.

Tilmes, Curt↗
NASA NTRS1996

Studies of Vestibular Neurons in Normal, Hyper- and Hypogravity

During the past year, pre-, in- and postflight studies were conducted in association with the Axon project for Bion 10 (Cosmos 2229). Recordings were made during pre- and postflight studies, from 118 horizontal semicircular canal afferents and 27 vestibular nucleus neurons in 7 rhesus monkeys; 137 pulse rotation protocols alone were executed (548 acceleration and deceleration responses were curve fit). Usable data was obtained from 127 horizontal afferents concerning their spontaneous discharge. Curve fits and analysis was made of sinusoidal and sum of sinusoidal responses from 42 and 35 horizontal afferents, respectively. Also recordings were made from neurons inflight from the two flight animals. The mean spontaneous rate varied from 128 spikes/sec. during preflight to 92 spikes/sec during postflight (day 5) - a change of 28%. In direct contrast to the results of Cosmos 2044, the best fitted neural adaptation operator (k) and the gain of the pulse response were decreased during post flight when compared to preflight. Surprisingly, the best fitted gain and k values for the sum of sines were slightly elevated during post flight tests. The gain and phase of single sine responses were compared for pre- and post flight tests and compared to a larger population of afferents. In contrast to Cosmos 2044 results where on the first day of post flight testing the gains of the best fitted sine response were skewed toward the higher values of the Miles and Braitman distribution, the gain of the best fitted sine responses during the first day of post flight testing (day 2) during Cosmos 2229 were exactly on the mode of the Miles and Braitman distribution. Thus, at least for the periodic stimuli, (pulses and sine waves) we found no change in gain and neural adaptation during post flight testing following Cosmos 2229. This conclusion is different from the one derived following the Cosmos 2044 flight. Cosmos flight 2229 differed from Cosmos flight 2044 in several significant ways: For example, during preflight, (1) The animals preflight training was different (less well trained on the gaze task) and (2) the animals were exposed to more experimental manipulations (surgical and rotational). Inflight, (1) the animals were required to make a pointing gesture (motor response) in association with eye movements to obtain reward, (2) the inflight diet was different (more balanced), (3) the feeder for one of the animals clogged following 9 days of flight resulting in evident dehydration and probably less head motion exposure in that monkey and (4) there was limited video taping of the monkeys in space. During postflight, (1) we were unable to test the flight animals until 26 hours postflight as compared to 14.5 hours during Cosmos 2044, (2) the animals received significantly more exposure to motion stimuli during postflight testing than during Cosmos 2044. These differences in the vestibular environment will require analysis of several parameters other than just neural and eye movement responses. For example, computer programs will have to be written and used to recover and quantify the number of head movements made by each animal during flight. This activity is critical to the production of neural adaptation and increased gain.

Correia, Manning J.↗
NASA NTRS1979

Publications of the planetary biology program for 1978: A special bibliography

The planetary events which are responsible for, or related to, the origin, evolution, and distribution of life in the universe are investigated. Bibliographies from chemical evolution, organic geochemistry, life detection, biological adaptation, bioinstrumentation, planetary environments, and origin of life studies are presented.

Pleasant, L. G.↗
NASA NTRS1984

An approach for automated analysis of particle holograms

A simple method for analyzing droplet holograms is proposed that is readily adaptable to automation using modern image digitizers and analyzers for determination of the number, location, and size distributions of spherical or nearly spherical droplets. The method determines these parameters by finding the spatial location of best focus of the droplet images. With this location known, the particle size may be determined by direct measurement of image area in the focal plane. Particle velocity and trajectory may be determined by comparison of image locations at different instants in time. The method is tested by analyzing digitized images from a reconstructed in-line hologram, and the results show that the method is more accurate than a time-consuming plane-by-plane search for sharpest focus.

Stanton, A. C.↗
NASA NTRS1994

Analytical models of the magnetic field of disk-shaped current sheets

Disk-shaped current distributions are useful tools in modeling the magnetospheres of Earth and other planets and have also been adapted for modeling the geotail. Such models usually start with an axisymmetric vector potential but may be modified to account for observed asymmetries, variable thickness, and warping in response to an inclined orientation of the planetary dipole axis. Models of this type until now either have lacked the ability to simulate a sharp inner edge of the current and to control accurately its falloff with distance or did not allow a simple analytical representation. Here existing methods will be reviewed, after which a new class of models which overcomes the above deficiencies and also allows the modeling of current disks of finite thickness flanked by current-free regions will be presented.

Tsyganenko, N. A.↗
NASA NTRS1999

Studies for the Loss of Atomic and Molecular Species from IO

The general objective of this project has been to advance our theoretical understanding of lo's atmosphere and how various atomic and molecular species are lost from this atmosphere and are distributed in the circumplanetary environment of Jupiter. This grant has provided support for the activities of Dr. Michael Combi at the University of Michigan to serve as a small part in collaboration with a larger project awarded to Atmospheric & Environmental Research, Inc., with primary principal investigator Dr. William H. Smyth. Dr. Combi is the Principal Investigator and Project Manager for the Michigan grant NAG5-6187. This Michigan grant has provided for a continuation of a collaboration between Drs. Smyth and Combi in related efforts beginning in 1981, and with the object to develop and apply sophisticated theoretical models to interpret and to relate a number of new and exciting observations for the atmospheric gases of the satellite. The ability to interpret and then to relate through the theoretical fabric a number of these otherwise independent observations are a central strength of this program. This comprehensive approach provides a collective power, extracting more from the sum of the parts and seeing beyond various limitations that are inherent in any one observation. Although the approach is designed to unify, the program is divided into well-defined studies for the likely dominant atmospheric gases involving species of the SO2 family (SO2, SO, O2, S and O) and for the trace atmospheric gas atomic sodium and a likely escaping molecular ion NaX(+) (where Na(X) is the atmospheric molecule and X represents one or more atoms).Attachments: IO's sodium corona and spatially cloud: a consistent flux speed distribution. and Io's plasma environment during the Galileo flyby: global three-dimensional MHD modeling with adaptive mesh refinement.

Combi, Michael R.↗
NASA NTRS2003

Novel Propulsion and Power Concepts for 21st Century Aviation

The air transportation for the new millennium will require revolutionary solutions to meeting public demand for improving safety, reliability, environmental compatibility, and affordability. NASA s vision for 21st Century Aircraft is to develop propulsion systems that are intelligent, virtually inaudible (outside the airport boundaries), and have near zero harmful emissions (CO2 and NO(x)). This vision includes intelligent engines that will be capable of adapting to changing internal and external conditions to optimally accomplish the mission with minimal human intervention. The distributed vectored propulsion will replace two to four wing mounted or fuselage mounted engines by a large number of small, mini, or micro engines. And the electric drive propulsion based on fuel cell power will generate electric power, which in turn will drive propulsors to produce the desired thrust. Such a system will completely eliminate the harmful emissions.

Sehra, Arun K.↗
NASA NTRS2003

Revolutionary Propulsion Systems for 21st Century Aviation

The air transportation for the new millennium will require revolutionary solutions to meeting public demand for improving safety, reliability, environmental compatibility, and affordability. NASA's vision for 21st Century Aircraft is to develop propulsion systems that are intelligent, virtually inaudible (outside the airport boundaries), and have near zero harmful emissions (CO2 and Knox). This vision includes intelligent engines that will be capable of adapting to changing internal and external conditions to optimally accomplish the mission with minimal human intervention. The distributed vectored propulsion will replace two to four wing mounted or fuselage mounted engines by a large number of small, mini, or micro engines, and the electric drive propulsion based on fuel cell power will generate electric power, which in turn will drive propulsors to produce the desired thrust. Such a system will completely eliminate the harmful emissions. This paper reviews future propulsion and power concepts that are currently under development at NASA Glenn Research Center.

Sehra, Arun K.↗
NASA NTRS1994

Distribution of cultivated and uncultivated cyanobacteria and Chloroflexus-like bacteria in hot spring microbial mats

Oligodeoxynucleotide hybridization probes were developed to complement specific regions of the small subunit (SSU) rRNA sequences of cultivated and uncultivated cyanobacteria and Chloroflexus-like bacteria, which inhabit hot spring microbial mats. The probes were used to investigate the natural distribution of SSU rRNAs from these species in mats of Yellowstone hot springs of different temperatures and pHs as well as changes in SSU rRNA distribution resulting from 1-week in situ shifts in temperature, pH, and light intensity. Synechococcus lividus Y-7c-s SSU rRNA was detected only in the mat of a slightly acid spring, from which it may have been initially isolated, or when samples from a more alkaline spring were incubated in the more acid spring. Chloroflexus aurantiacus Y-400-fl SSU rRNA was detected only in a high-temperature mat sample from the alkaline Octopus Spring or when lower-temperature samples from this mat were incubated at the high-temperature site. SSU rRNAs of uncultivated species were more widely distributed. Temperature distributions and responses to in situ temperature shifts suggested that some of the uncultivated cyanobacteria might be adapted to high-, moderate-, and low-temperature ranges whereas an uncultivated Chloroflexus-like bacterium appears to have broad temperature tolerance. SSU rRNAs of all uncultivated species inhabiting a 48 to 51 degrees C Octopus Spring mat site were most abundant in the upper 1 mm and were not detected below a 2.5-to 3.5-mm depth, a finding consistent with their possible phototrophic nature. However, the effects of light intensity reduction on these SSU rRNAs were variable, indicating the difficulty of demonstrating a phototrophic phenotype in light reduction experiments.

Non-NASA Center↗
NASA NTRS2013

Ground Water and Climate Change

As the world's largest distributed store of fresh water, ground water plays a central part in sustaining ecosystems and enabling human adaptation to climate variability and change. The strategic importance of ground water for global water and food security will probably intensify under climate change as more frequent and intense climate extremes (droughts and floods) increase variability in precipitation, soil moisture and surface water. Here we critically review recent research assessing the impacts of climate on ground water through natural and human-induced processes as well as through groundwater-driven feedbacks on the climate system. Furthermore, we examine the possible opportunities and challenges of using and sustaining groundwater resources in climate adaptation strategies, and highlight the lack of groundwater observations, which, at present, limits our understanding of the dynamic relationship between ground water and climate.

climate change↗
NASA NTRS2022

Wichita Climate II: Quantifying and Mapping Urban Heat to Inform Equitable and Sustainable Urban Planning Initiatives in Wichita, Kansas

Wichita, Kansas is experiencing a host of climate threats, particularly extreme heat manifested through Urban Heat Islands (UHI). Heat is unevenly distributed within cities due to factors such as income inequality, historical discriminatory practices like redlining, and divestment in neighborhoods of color. This leads to less vegetation and more heat-absorbing infrastructure in specific communities. Moreover, adverse effects of heat, including heat-related morbidity and mortality, disproportionately impact populations that experience vulnerability through social inequities and structural discrimination. Heat vulnerability is a combination of the factors of heat exposure, sensitivity, and adaptive capacity, and can be harnessed to guide urban heat interventions. This DEVELOP project partnered with the City of Wichita to understand the spatial distribution and drivers of UHIs and heat vulnerability indicators. The team modeled outcomes of tree cover interventions using Landsat 8’s Thermal Infrared Sensor (TIRS) and Operational Land Imager (OLI), Landsat 9 TIRS-2 and OLI-2, and the International Space Station’s Ecosystem Spaceborne Thermal Radiometer Experiment on the International Space Station (ECOSTRESS) sensor, along with the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) Urban Cooling model. The team also leveraged statistical analysis by implementing principal component analysis to develop a heat vulnerability index (HVI) specific to Wichita. Ultimately, the project’s outputs will inform the City of Wichita’s Climate Adaptation and Mitigation Plan, identify priority areas for heat mitigation initiatives, and be used in public-facing communications to educate communities on the impacts of urban heat.

Environmental Justice↗
NASA NTRS1991

The AI Bus architecture for distributed knowledge-based systems

The AI Bus architecture is layered, distributed object oriented framework developed to support the requirements of advanced technology programs for an order of magnitude improvement in software costs. The consequent need for highly autonomous computer systems, adaptable to new technology advances over a long lifespan, led to the design of an open architecture and toolbox for building large scale, robust, production quality systems. The AI Bus accommodates a mix of knowledge based and conventional components, running on heterogeneous, distributed real world and testbed environment. The concepts and design is described of the AI Bus architecture and its current implementation status as a Unix C++ library or reusable objects. Each high level semiautonomous agent process consists of a number of knowledge sources together with interagent communication mechanisms based on shared blackboards and message passing acquaintances. Standard interfaces and protocols are followed for combining and validating subsystems. Dynamic probes or demons provide an event driven means for providing active objects with shared access to resources, and each other, while not violating their security.

Schultz, Roger D.↗
NASA NTRS1998

Mapping the Distribution of Wildfire Fuels Using AVIRIS in the Santa Monica Mountains

Catastrophic wildfires, such as the 1990 Painted Cave Fire in Santa Barbara or Oakland fire of 1991, attest to the destructive potential of fire in the wildland/urban interface. For example, during the Painted Cave Fire, 673 structures were consumed over a period of only six hours at an estimated cost of 250 million dollars (Gomes et al., 1993). One of the primary sources of fuels is chaparral, which consists of plant species that are adapted to frequent fires and may actually promote its ignition and spread of through volatile organic compounds in foliage. As one of the most widely distributed plant communities in Southern California, and one of the most common vegetation types along the wildland urban interface, chaparral represents one of the greatest sources of wildfire hazard in the region. An ongoing NASA funded research project was initiated in 1994 to study the potential of AVIRIS for mapping wildfire fuel properties in Southern California chaparral. The project was initiated in the Santa Monica Mountains, an east-west trending range in western Los Angeles County that has experienced extremely high fire frequencies over the past 70 years. The Santa Monica Mountains were selected because they exemplify many of the problems facing the southwest, forming a complex mosaic of land ownership intermixed with a diversity of chaparral age classes and fuel loads. Furthermore, the area has a wide diversity of chaparral community types and a rich background in supporting geographic information including fire history, soils and topography. Recent fires in the Santa Monica Mountains, including several in 1993 and the Calabasas fire of 1996 attest to the active fire regime present in the area. The long term objectives of this project are to improve existing maps of wildland fuel properties in the area, link AVIRIS derived products to fuel models under development for the region, then predict fire hazard through models that simulate fire spread. In this paper, we describe the AVIRIS derived products we are developing to map wildland fuels.

Roberts, Dar↗
NASA NTRS1989

Embedded adaptation for time dependent real fluid/gas flows

An embedded adaptation algorithm is used to illustrate applications and requirements for Navier-Stokes and nonequilibrium unsteady two-dimensional flow fields. Both grid refinement and equation modification are included for unstructured distributions of quadrilateral cells. Multiple refinement parameters for distinct physical phenomena serve to monitor the evolving nonuniform field and to recognize flow features in isolated and overlapping subdomains. Examples from subsonic, hypersonic, internal, and external fields show substantial advantages for the adaptive approach.

Baron, Judson R.↗
NASA NTRS1989

Adaptive structures; Proceedings of the ASME Winter Annual Meeting, San Francisco, CA, Dec. 10-15, 1989

The present conference on adaptive structures discusses piezoelectric and electrostrictive sensors and actuators for adaptive structures and smart materials, real-time control for composite structures with embedded actuators and sensors, a laminated-shell theory incorporating embedded distributed actuators, traveling-wave power flow techniques, uncertainty modeling for the control of an active structure, and active vibration isolation in the presence of unmodeled structural dynamic response. Also discussed are the control of flexible beams via free-free active truss, truss structure control using member actuators with latch mechanism, neural processors for smart-structure control, the effect of imperfections on the static control of adaptive structures, adaptive structures for segmented optical systems, and the shape-control of flexible structures.

Wada, Ben K.↗
NASA NTRS1991

The walking robot project

A walking robot was designed, analyzed, and tested as an intelligent, mobile, and a terrain adaptive system. The robot's design was an application of existing technologies. The design of the six legs modified and combines well understood mechanisms and was optimized for performance, flexibility, and simplicity. The body design incorporated two tripods for walking stability and ease of turning. The electrical hardware design used modularity and distributed processing to drive the motors. The software design used feedback to coordinate the system and simple keystrokes to give commands. The walking machine can be easily adapted to hostile environments such as high radiation zones and alien terrain. The primary goal of the leg design was to create a leg capable of supporting a robot's body and electrical hardware while walking or performing desired tasks, namely those required for planetary exploration. The leg designers intent was to study the maximum amount of flexibility and maneuverability achievable by the simplest and lightest leg design. The main constraints for the leg design were leg kinematics, ease of assembly, degrees of freedom, number of motors, overall size, and weight.

Williams, P.↗