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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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NASA NTRS1986

The TAVERNS emulator: An Ada simulation of the space station data communications network and software development environment

The Space Station DMS (Data Management System) is the onboard component of the Space Station Information System (SSIS) that includes the computers, networks and software that support the various core and payload subsystems of the Space Station. TAVERNS (Test And Validation Environment for Remote Networked Systems) is a distributed approach for development and validation of application software for Space Station. The TAVERNS concept assumes that the different subsystems will be developed by different contractors who may be geographically separated. The TAVERNS Emulator is an Ada simulation of a TAVERNS on the ASD VAX. The software services described in the DMS Test Bed User's Manual are being emulated on the VAX together with simulations of some of the core subsystems and a simulation of the DCN. The TAVERNS Emulator will be accessible remotely from any VAX that can communicate with the ASD VAX.

Howes, Norman R.↗

NASA NTRS1989

Brayton advanced heat receiver development program

NASA Lewis Research Center is managing an advanced solar dynamic (ASD) space power program. The objective of the ASD program is to develop small and lightweight solar dynamic systems which show significant improvement in efficiency and specific mass over the baseline design derived from the Space Station Freedom technology. The advanced heat receiver development program is a phased program to design, fabricate and test elements of a 7-kWe heat-receiver/thermal-energy-storage subsystem. Receivers for both Brayton and Stirling heat engines are being developed under separate contracts. Phase I, described here, is the current eighteen month effort to design and perform critical technology experiments on innovative concepts designed to reduce mass without compromising thermal efficiency and reliability.

Heidenreich, G. R.↗

NASA NTRS1995

Library reuse in a rapid development environment

The Aeroscience and Flight Mechanics Division (AFMD) established a Rapid Development Laboratory (RDL) to investigate and improve new 'rapid development' software production processes and refine the use of commercial, off-the-shelf (COTS) tools. These tools and processes take an avionics design project from initial inception through high fidelity, real-time, hardware-in-the-loop (HIL) testing. One central theme of a rapid development process is the use and integration of a variety of COTS tools: This paper discusses the RDL MATRIX(sub x)(R) libraries, as well as the techniques for managing and documenting these libraries. This paper also shows the methods used for building simulations with the Advanced Simulation Development System (ASDS) libraries, and provides metrics to illustrate the amount of reuse for five complete simulations. Combining ASDS libraries with MATRIX(sub x)(R) libraries is discussed.

Uhde, JO↗

NASA NTRS1995

Flight demonstration of integrated airport surface automation concepts

A flight demonstration was conducted to address airport surface movement area capacity issues by providing pilots with enhanced situational awareness information. The demonstration showed an integration of several technologies to government and industry representatives. These technologies consisted of an electronic moving map display in the cockpit, a Differential Global Positioning System (DGPS) receiver, a high speed VHF data link, an ASDE-3 radar, and the Airport Movement Area Safety System (AMASS). Aircraft identification was presented to an air traffic controller on AMASS. The onboard electronic map included the display of taxi routes, hold instructions, and clearances, which were sent to the aircraft via data link by the controller. The map also displayed the positions of other traffic and warning information, which were sent to the aircraft automatically from the ASDE-3/AMASS system. This paper describes the flight demonstration in detail, along with preliminary results.

Jones, Denise R.↗

NASA NTRS1998

Flight Demonstration of Integrated Airport Surface Technologies for Increased Capacity and Safety

A flight demonstration was conducted to address airport surface movement area capacity and safety issues by providing pilots with enhanced situational awareness information. The demonstration presented an integration of several technologies to government and industry representatives. These technologies consisted of an electronic moving map display in the cockpit, a Differential Global Positioning system (DGPS) receiver, a high speed very high frequency (VHF) data link, an Airport Surface Detection Equipment (ASDE-3) radar, and the Airport Movement Area Safety System (AMASS). Aircraft identification was presented to an air traffic controller on an AMASS display. The onboard electronic map included the display of taxi routes, hold instructions, and clearances, which were sent to the aircraft via data link by the controller. The map also displayed the positions of other traffic and warning information, which were sent to the aircraft automatically from the ASDE-3/AMASS system. This paper describes the flight demonstration in detail, along with test results.

Jones, Denise R.↗

NASA NTRS1998

Astronomical Software Directory Service

This is the final report on the development of the Astronomical Software Directory Service (ASDS), a distributable, searchable, WWW-based database of software packages and their related documentation. ASDS provides integrated access to 56 astronomical software packages, with more than 16,000 URL's indexed for full-text searching.

Hanisch, R. J.↗

NASA NTRS1995

Flight Demonstration of Integrated Airport Surface Automation Concepts

Jones, Denise R.↗

NASA NTRS1996

Effects of pressure- or volume-overload hypertrophy on passive stiffness in isolated adult cardiac muscle cells

It has been hypothesized that the changes in myocardial stiffness induced by chronic hemodynamic overloading are dependent on changes in the passive stiffness of the cardiac muscle cell (cardiocyte). However, no previous studies have examined the passive constitutive properties of cardiocytes isolated from animals with myocardial hypertrophy. Accordingly, changes in relative passive stiffness of cardiocytes isolated from animals with chronic pressure- or volume-overload hypertrophy were determined by examining the effects of anisosmotic stress on cardiocyte size. Anisosmotic stress was produced by altering superfusate osmolarity. Hypertrophied cardiocytes were enzymatically isolated from 16 adult cats with right ventricular (RV) pressure-overload hypertrophy induced by pulmonary artery banding (PAB) and from 6 adult cats with RV volume-overload hypertrophy induced by creating an atrial septal defect (ASD). Left ventricular (LV) cardiocytes from each cat served as nonhypertrophied, normally loaded, same-animal controls. Superfusate osmolarity was decreased from 305 +/- 3 to 135 +/- 5 mosM and increased to 645 +/- 4 mosM. During anisosmotic stress, there were no significant differences between hypertrophied RV and normal LV cardiocytes in pressure overload PAB cats with respect to percent change in cardiocyte area (47 +/- 2% in RV vs. 48 +/- 2% in LV), diameter (46 +/- 3% in RV vs. 48 +/- 2% in LV), or length (2.4 +/- 0.2% in RV vs. 2.0 +/- 0.3% in LV), or sarcomere length (1.5 +/- 0.1% in RV vs. 1.3 +/- 0.3% in LV). Likewise, there were no significant differences in cardiocyte strain between hypertrophied RV and normal LV cardiocytes from ASD cats. In conclusion, chronic pressure-overload hypertrophy and chronic volume-overload hypertrophy did not alter the cardiocyte response to anisosmotic stress. Thus chronic overload hypertrophy did not alter relative passive cardiocyte stiffness.

Non-NASA Center↗

NASA NTRS2005

Evaluation of NASA Data Products for RPO Applications

This presentation summarizes preliminary investigations at SSC by NASA's ASD in Air Quality including decision support tools, partner plans, working groups, and committees. An overview of follow-on short-term and long-term objectives is also provided. A table of potential NASA sensors for use with air quality applications is included, along with specifications for MODIS 04 and 06 products. This presentation was originally given by Rich Piorot of the Vermont Department of Environmental Conservation - Air Quality as part of a round-table discussion during "Exploring Collaborative Opportunities in Air Quality Monitoring, Modelling and Communication Workshop" in Boulder, CO, on March 21-22, 2005; verbal consent for this presentation to be provided to Mr. Piorot was given by the NASA SSC ASD Air Quality Program Manager on March 14, 2005.

Frisbie, Troy↗

NASA NTRS2006

Radiometric Characterization Results for the IKONOS, Quickbird, and OrbView-3 Sensor

Radiometric calibration of commercial imaging satellite products is required to ensure that science and application communities better understand commercial imaging satellite properties. Inaccurate radiometric calibrations can lead to erroneous decisions and invalid conclusions and can limit intercomparisons with other systems. To address this calibration need, the NASA Applied Sciences Directorate (ASD) at Stennis Space Center established a commercial satellite imaging radiometric calibration team consisting of three independent groups: NASA ASD, the University of Arizona Remote Sensing Group, and South Dakota State University. Each group independently determined the absolute radiometric calibration coefficients of available high-spatial-resolution commercial 4-band multispectral products, in the visible though near-infrared spectrum, from GeoEye(tradeMark) (formerly SpaceImaging(Registered TradeMark)) IKONOS, DigitalGlobe(Regitered TradeMark) QuickBird, and GeoEye (formerly ORBIMAGE(Registered TradeMark) OrbView. Each team member employed some variant of reflectance-based vicarious calibration approach, requiring ground-based measurements coincident with image acquisitions and radiative transfer calculations. Several study sites throughout the United States that covered a significant portion of the sensor's dynamic range were employed. Satellite at-sensor radiance values were compared to those estimated by each independent team member to evaluate the sensor's radiometric accuracy. The combined results of this evaluation provide the user community with an independent assessment of these sensors' absolute calibration values.

Holekamp, Kara↗

NASA NTRS2006

Verification and Validation of NASA-Supported Enhancements to PECAD's Decision Support Tools

The NASA Applied Sciences Directorate (ASD), part of the Earth-Sun System Division of NASA's Science Mission Directorate, has partnered with the U.S. Department of Agriculture (USDA) to enhance decision support in the area of agricultural efficiency-an application of national importance. The ASD integrated the results of NASA Earth science research into USDA decision support tools employed by the USDA Foreign Agricultural Service (FAS) Production Estimates and Crop Assessment Division (PECAD), which supports national decision making by gathering, analyzing, and disseminating global crop intelligence. Verification and validation of the following enhancements are summarized: 1) Near-real-time Moderate Resolution Imaging Spectroradiometer (MODIS) products through PECAD's MODIS Image Gallery; 2) MODIS Normalized Difference Vegetation Index (NDVI) time series data through the USDA-FAS MODIS NDVI Database; and 3) Jason-1 and TOPEX/Poseidon lake level estimates through PECAD's Global Reservoir and Lake Monitor. Where possible, each enhanced product was characterized for accuracy, timeliness, and coverage, and the characterized performance was compared to PECAD operational requirements. The MODIS Image Gallery and the GRLM are more mature and have achieved a semi-operational status, whereas the USDA-FAS MODIS NDVI Database is still evolving and should be considered

McKellipo, Rodney↗

NASA NTRS2006

Laboratory Measurement of Bidirectional Reflectance of Radiometric Tarps

Objectives: a) To determine the magnitude of radiometric tarp BRDF; b) To determine whether an ASD FieldSpec Pro spectroradiometer can be used to perform the experiment. Radiometric tarps with nominal reflectance values of 52%, 35%, and 3.5%, deployed for IKONOS. QuickBird, and OrbView-3 overpasses Ground-based spectroradiometric measurements of tarp and Spectralon@ panel taken during overpass using ASD FieldSpec Pro spectroradiometer, and tarp reflectance calculated. Reflectance data used in atmospheric radiative transfer model (MODTRAN) to predict satellite at-sensor radiance for radiometric calibration. Reflectance data also used to validate atmospheric correction of high-spatial-resolution multispectral image products

Knowlton, Kelly↗

NASA NTRS2008

Software Performs Complex Design Analysis

Designers use computational fluid dynamics (CFD) to gain greater understanding of the fluid flow phenomena involved in components being designed. They also use finite element analysis (FEA) as a tool to help gain greater understanding of the structural response of components to loads, stresses and strains, and the prediction of failure modes. Automated CFD and FEA engineering design has centered on shape optimization, which has been hindered by two major problems: 1) inadequate shape parameterization algorithms, and 2) inadequate algorithms for CFD and FEA grid modification. Working with software engineers at Stennis Space Center, a NASA commercial partner, Optimal Solutions Software LLC, was able to utilize its revolutionary, one-of-a-kind arbitrary shape deformation (ASD) capability-a major advancement in solving these two aforementioned problems-to optimize the shapes of complex pipe components that transport highly sensitive fluids. The ASD technology solves the problem of inadequate shape parameterization algorithms by allowing the CFD designers to freely create their own shape parameters, therefore eliminating the restriction of only being able to use the computer-aided design (CAD) parameters. The problem of inadequate algorithms for CFD grid modification is solved by the fact that the new software performs a smooth volumetric deformation. This eliminates the extremely costly process of having to remesh the grid for every shape change desired. The program can perform a design change in a markedly reduced amount of time, a process that would traditionally involve the designer returning to the CAD model to reshape and then remesh the shapes, something that has been known to take hours, days-even weeks or months-depending upon the size of the model.

Source record↗

NASA NTRS2009

The Astrophysics Science Division Annual Report 2008

The Astrophysics Science Division (ASD) at Goddard Space Flight Center (GSFC) is one of the largest and most diverse astrophysical organizations in the world, with activities spanning a broad range of topics in theory, observation, and mission and technology development. Scientific research is carried out over the entire electromagnetic spectrum from gamma rays to radio wavelengths as well as particle physics and gravitational radiation. Members of ASD also provide the scientific operations for three orbiting astrophysics missions WMAP, RXTE, and Swift, as well as the Science Support Center for the Fermi Gamma-ray Space Telescope. A number of key technologies for future missions are also under development in the Division, including X-ray mirrors, and new detectors operating at gamma-ray, X-ray, ultraviolet, infrared, and radio wavelengths. This report includes the Division's activities during 2008.

Oegerle, William↗

NASA NTRS2010

The Application of Modeling and Simulation to the Behavioral Deficit of Autism

This abstract describes a research effort to apply technological advances in virtual reality simulation and computer-based games to create behavioral modification programs for individuals with Autism Spectrum Disorder (ASD). The research investigates virtual social skills training within a 3D game environment to diminish the impact of ASD social impairments and to increase learning capacity for optimal intellectual capability. Individuals with autism will encounter prototypical social contexts via computer interface and will interact with 3D avatars with predefined roles within a game-like environment. Incremental learning objectives will combine to form a collaborative social environment. A secondary goal of the effort is to begin the research and development of virtual reality exercises aimed at triggering the release of neurotransmitters to promote critical aspects of synaptic maturation at an early age to change the course of the disease.

Anton, John J.↗

NASA NTRS2018

Improving the Performance of the OMPS Limb Profiling Instrument in Monitoring Aerosols in the Post-Pinatubo Stratosphere

The OMPS Limb Profiling (LP) instrument was launched on NOAA's Suomi NPP (SNPP) weather satellite in October 2011. The instrument measures limb-scattered radiation in the ultraviolet, visible and NIR wavelengths with high vertical resolution (~2 km) and relatively dense spatial and temporal sampling (several thousand measurements/day covering the entire sunlit globe). These measurements have very high sensitivity to stratospheric aerosols due to long path of the incoming solar photons through the aerosol layer. However, unlike the recently launched ISS/SAGE III that directly measures extinction of solar/lunar radiation by gases and particles along the line of sight (LOS) of the instrument, information content of OMPS LP measurements is complex. It consists of solar radiation singly scattered and attenuated by aerosols, air, and trace gases along the LOS of the instrument, as well as diffuse upwelling radiation from the lower atmosphere that also gets scattered and attenuated into the LOS. To unscramble this complex signal one needs to have good knowledge of aerosol size distribution (ASD) and their complex refractive index. We will describe our recent efforts in constraining the ASD parameters by analyzing in-situ balloon data from Laramie, Wyoming; aerosol microphysical model data from CARMA; and spectral information provided by OMPS LP. We will also discuss our proposed methodology to reï¬ne this information by adjusting the microphysical properties of the aerosols to make data from various occultation and scattering instruments internally consistent. This is a generalized version of the technique employed by AERONET in which solar extinction data are combined with scattered radiation measured by the almucantar technique to determine aerosol particle shape, complex refractive index and size distribution. We suggest that such closure studies are essential to develop confidence in space-based data to validate aerosol microphysical models, such as CARMA, and aerosol chemistry- transport models, such as GOCART, and for estimating radiative forcing due to stratospheric aerosols in both volcanic and quiescent time periods.

Bhartia, P. K.↗

NASA NTRS2018

Hybridized Agile Software Development of Flight Control Team Tools for International Space Station's Payload Operations Integration Center

Ground systems operations at the National Aeronautics and Space Administration's (NASA) Payload Operations and Integration Center (POIC) at Marshall Space Flight Center (MSFC) recently increased via a High Operations Tempo (HOT) initiative, in order to support more science activities with a fourth crew member on the International Space Station (ISS). The Flight Control Team's (FCT) need to support this increasing pace of payload science operations was the impetus for creating a series of new tools. While their need was clear, the full scope and user experience for each tool was not as well-understood, thus establishing a fixed set of initial requirements was not feasible. A hybridized Agile Software Development (ASD) paradigm was created to take advantage of this uncertainty, plan for it, permit the exploration of novel concepts, and also facilitate a rapid and flexible response to inevitably changing requirements. The POIC's hybridized ASD approach places preeminent focus on providing customer value through the delivery of high quality, customer-focused solutions in short timeframes. This has been successfully achieved through creating unprecedented modes of cooperation and collaboration between operations and software development teams, frequent user evaluations of the software with well-defined feedback mechanisms, increased human factors involvement, and a dedication to successful outcomes by the whole of the POIC. Since space science operations and software development are not typically so closely linked, this paper discusses an approach that offers an optimal way to provide an increased return on investment and a faster time-to-completion than traditional software development paradigms, while aiming at delivering high quality products and customer-driven value.

Albers, Cerese M.↗

NASA NTRS2019

Radiometric Calibration of A Non-Imaging Airborne Spectrometer To Measure the Greenland Ice Sheet Surface

Methods to radiometrically calibrate a non-imaging airborne visible-to-shortwave infrared (VSWIR) spectrometer to measure the Greenland ice sheet surface are presented. Airborne VSWIR measurement performance for bright Greenland ice and dark bare rock/soil targets is compared against the MODerate resolution atmospheric TRANsmission (MODTRAN ® ) radiative transfer code (version 6.0), and a coincident Landsat 8 Operational Land Imager (OLI) acquisition on 29 July 2015 during an in-flight radiometric calibration experiment. Airborne remote sensing flights were carried out in northwestern Greenland in preparation for the Ice, Cloud, and land Elevation Satellite 2 (ICESat-2) laser altimeter mission. A total of nine science flights were conducted over the Greenland ice sheet, sea ice, and open-ocean water. The campaign's primary purpose was to correlate green laser pulse penetration into snow and ice with spectroscopic-derived surface properties. An experimental airborne instrument configuration that included a nadir-viewing (looking downward at the surface) non-imaging Analytical Spectral Devices (ASD) Inc. spectrometer that measured upwelling VSWIR (0.35 to 2.5 µm) spectral radiance (Wm −2 sr −1 µm −1 ) in the two-color Slope Imaging Multi-polarization Photon-Counting Lidar's (SIMPL) ground instantaneous field of view, and a zenith-viewing (looking upward at the sky) ASD spectrometer that measured VSWIR spectral irradiance (W m −2 nm −1 ) was flown. National Institute of Standards and Technology (NIST) traceable radiometric calibration procedures for laboratory, in-flight, and field environments are described in detail to achieve a targeted VSWIR measurement requirement of within 5 % to support calibration/validation efforts and remote sensing algorithm development. Our MODTRAN predictions for the 29 July flight line over dark and bright targets indicate that the airborne nadir-viewing spectrometer spectral radiance measurement uncertainty was between 0.6 % and 4.7 % for VSWIR wavelengths (0.4 to 2.0 µm) with atmospheric transmittance greater than 80 %. MODTRAN predictions for Landsat 8 OLI relative spectral response functions suggest that OLI is measuring 6 % to 16 % more top-of-atmosphere (TOA) spectral radiance from the Greenland ice sheet surface than was predicted using apparent reflectance spectra from the nadir-viewing spectrometer. While more investigation is required to convert airborne VSWIR spectral radiance into atmospherically corrected airborne surface reflectance, it is expected that airborne science flight data products will contribute to spectroscopic determination of Greenland ice sheet surface optical properties to improve understanding of their potential influence on ICESat-2 measurements.

Christopher J. Crawford↗