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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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All sourcesNASA NTRSDOE OSTI
NASA NTRS2012

Prediction of BVI Noise for an Active Twist Rotor Using a Loosely Coupled CFD/CSD Method and Comparison to Experimental Data

Numerical predictions of the acoustic characteristics of an Active Twist Rotor (ATR), using two methods to compute the rotor blade aerodynamics and elastic blade motion are compared to experimental data from a wind tunnel test in the NASA Langley Transonic Dynamics Tunnel (TDT) in 2000. The first method, a loosely coupled iterative method, utilizes the Computational Fluid Dynamics (CFD) code OVERFLOW 2 and the Computational Structural Dynamics (CSD) code CAMRAD II. The second method utilizes the CAMRAD II free-wake model only. The harmonic active-twist control to the main rotor blade system is identified with three parameters - harmonic actuation frequency, actuation amplitude, and control phase angle. The resulting aerodynamics and blade motion data from the two methods are then used in the acoustics code PSU-WOPWOP to predict acoustic pressure on a spherical array of equally spaced observers surrounding the rotor. This spherical distribution of pressure is used to compute the sound power level representing baseline and actuated conditions. Sound power levels for three categories of noise are defined as - blade-vortex interaction sound power level (BVIPWL), low frequency sound power level (LFPWL), and overall sound power level, OAPWL. Comparisons with measured data indicate the CFD/CSD analysis successfully captures the trends in sound power levels and the effects of active-twist control at advance ratios of 0.14 and 0.17. The free-wake model predictions show inconsistent sound power levels relative to the trends in the experimental and CFD data. This paper presents the first ever comparison between CFD/CSD acoustic predictions for an active-twist rotor and experimental measurements.

Fogarty, David E.↗
DOE OSTI2021

A Proposed Geospatial Data Preservation Strategy for DOE's Office of Legacy Management

Identifying and planning preservation and curation activities associated with geospatial data will improve the ability of the U.S. Department of Energy Office of Legacy Management (LM) to support their core mission of protecting human health and the environment. This report documents the development LM's strategy for preserving and curating geospatial data within the context of LM's data-lifecycle-management framework. The strategy consists of preservation and curation elements, specific activities, and key enabling factors that ensure LM's geospatial data is maintained. Preservation elements enable the effective preservation of LM's geospatial data and recognizes that strategies need to be flexible to adapt to ongoing changes in scale, technology, and standards. Key enabling factors are intended to highlight critical data management responsibilities that must be addressed by LM to meet its preservation and curation objectives. A summary of best practices for geospatial data preservation is provided as part of the strategy.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2016

A GATE evaluation of the sources of error in quantitative {sup 90}Y PET

Purpose: Accurate reconstruction of the dose delivered by {sup 90}Y microspheres using a postembolization PET scan would permit the establishment of more accurate dose–response relationships for treatment of hepatocellular carcinoma with {sup 90}Y. However, the quality of the PET data obtained is compromised by several factors, including poor count statistics and a very high random fraction. This work uses Monte Carlo simulations to investigate what impact factors other than low count statistics have on the quantification of {sup 90}Y PET. Methods: PET acquisitions of two phantoms—a NEMA PET phantom and the NEMA IEC PET body phantom-containing either {sup 90}Y or {sup 18}F were simulated using GATE. Simulated projections were created with subsets of the simulation data allowing the contributions of random, scatter, and LSO background to be independently evaluated. The simulated projections were reconstructed using the commercial software for the simulated scanner, and the quantitative accuracy of the reconstruction and the contrast recovery of the reconstructed images were evaluated. Results: The quantitative accuracy of the {sup 90}Y reconstructions were not strongly influenced by the high random fraction present in the projection data, and the activity concentration was recovered to within 5% of the known value. The contrast recovery measured for simulated {sup 90}Y data was slightly poorer than that for simulated {sup 18}F data with similar count statistics. However, the degradation was not strongly linked to any particular factor. Using a more restricted energy range to reduce the random fraction in the projections had no significant effect. Conclusions: Simulations of {sup 90}Y PET confirm that quantitative {sup 90}Y is achievable with the same approach as that used for {sup 18}F, and that there is likely very little margin for improvement by attempting to model aspects unique to {sup 90}Y, such as the much higher random fraction or the presence of bremsstrahlung in the singles data.

61 RADIATION PROTECTION AND DOSIMETRY↗
NASA NTRS1993

Tumuli and tubes: Teaching scientific techniques

Planetary and space science is the best way to teach basic chemistry, physics, and math. Einstein once said that 'man is drawn to the mysterious and it is from that that we achieve true art and science.' Planets and the processes that shape them are especially mysterious and fascinating to students, young and old, and because of this planetary geology kindles interest that draws them further into the world of science. At the very least, they are engaged enough to learn how science works, a key ingredient in scientific literacy. A project involving field measurements on Kilauea volcano, Hawaii, by a Geology 101 honors class is described. Hawaii is blessed with spectacular, active, accessible, and relatively safe basaltic eruptions. The study of volcanoes, the landforms they produce, and the processes that operate on and in volcanoes, combined with the study of volcanoes on the other planets, is an excellent way to link aspects of Hawaiian geology to the planets. During the past year we have taken advantage of our setting to organize a NASA field workshop for junior investigators and senior graduate students, made field trips and planetary volcanism the centerpieces of our annual Summer Workshop for Teachers, and led a field trip around Kilauea Volcano during the Challenger Center Faculty Development conference, held on the island of Hawaii last summer. An activity for the honors Geology 101 class (all undergraduates) at the University of Hawaii is presently being planned. Our goal is to give them some hands on experience working on a field project and applying what they have learned to planetary volcanoes. The work will include qualitative observations and quantitative measurements on volcanic lava flows. Follow-up activities will involve data analysis. The trip requires planning (at least 3 months before hand) everything from accommodations and insurance to the actual activities we will be doing. Our goal is to stimulate interest and awareness in the students' surroundings, in this case, volcanoes, and to include planetary applications and how studies of terrestrial geology greatly aids studies of the other planets. Two studies are planned both of which are active research projects being conducted by the authors. These projects, tumuli in pahoehoe flow fileds and lava tube cross-secational areas, are described.

Tatsumura, Michelle J.↗
DOE OSTI2019

Replication Data for: Single Nickel Atoms Anchored on Nitrogen-Doped Graphene as a Highly Active Cocatalyst for Photocatalytic H2 Evolution

The data underlying this published work have been made publicly available in this repository as part of the IMASC Data Management Plan. This work was supported as part of the Integrated Mesoscale Architectures for Sustainable Catalysis (IMASC), an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences under Award # DE-SC0012573.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2017

Structure and Dynamics of FosA-Mediated Fosfomycin Resistance in Klebsiella pneumoniae and Escherichia coli

ABSTRACT Fosfomycin exhibits broad-spectrum antibacterial activity and is being reevaluated for the treatment of extensively drug-resistant pathogens. Its activity in Gram-negative organisms, however, can be compromised by expression of FosA, a metal-dependent transferase that catalyzes the conjugation of glutathione to fosfomycin, rendering the antibiotic inactive. In this study, we solved the crystal structures of two of the most clinically relevant FosA enzymes: plasmid-encoded FosA3 from Escherichia coli and chromosomally encoded FosA from Klebsiella pneumoniae (FosA KP ). The structure, molecular dynamics, catalytic activity, and fosfomycin resistance of FosA3 and FosA KP were also compared to those of FosA from Pseudomonas aeruginosa (FosA PA ), for which prior crystal structures exist. E. coli TOP10 transformants expressing FosA3 and FosA KP conferred significantly greater fosfomycin resistance (MIC, >1,024 μg/ml) than those expressing FosA PA (MIC, 16 μg/ml), which could be explained in part by the higher catalytic efficiencies of the FosA3 and FosA KP enzymes. Interestingly, these differences in enzyme activity could not be attributed to structural differences at their active sites. Instead, molecular dynamics simulations and hydrogen-deuterium exchange experiments with FosA KP revealed dynamic interconnectivity between its active sites and a loop structure that extends from the active site of each monomer and traverses the dimer interface. This dimer interface loop is longer and more extended in FosA KP and FosA3 than in FosA PA , and kinetic analyses of FosA KP and FosA PA loop-swapped chimeric enzymes highlighted its importance in FosA activity. Collectively, these data yield novel insights into fosfomycin resistance that could be leveraged to develop new strategies to inhibit FosA and potentiate fosfomycin activity.

Klontz, Erik H.↗
NASA NTRS2008

The Virtual Wave Observatory (VWO)

Heliophysics wave data are currently not easily searchable by computers, making identifying pertinent wave data features for analyses and cross comparisons difficult and laborious. Since wave data analysis requires specialized knowledge about waves, which spans the spectrum of microphysics to macrophysics, researchers having varied expertise cannot easily use wave data. To resolve these difficulties and to allow wave data to contribute more fully to Heliophysics research, we are developing a Virtual Wave Observatory (VWO) whose goal is to enable all Heliophysics wave data to become searchable, understandable and usable by the Heliophysics community. The VWO objective is to enable search of multiple and distributed wave data (from both active and passive measurements). This presentation provides and overview of the VWO, a new VxO component within the emerging distributed Heliophysics data and model environment.

Fung, Shing F.↗
NASA NTRS2013

BKG Data Center

This report summarizes the activities and background information of the IVS Data Center for the year 2012. Included is information about functions, structure, technical equipment, and staff members of the BKG Data Center.

Thorandt, Volkmar↗
DOE OSTI2018

Spatially Explicit Modeling of Criteria Air Pollutants from Agricultural and Forestry Feedstock Production

The Feedstock Production Emissions to Air Model (FPEAM) is a spatially explicit supply chain model that quantifies criteria air pollutants and precursors generated by biomass production, harvest and transportation to biorefineries. FPEAM was most recently used for the 2016 Billion Ton Study (BTS) published by the U.S. Department of Energy Bioenergy Technologies Office. This presentation describes several use cases for the model, and provides an overview of recent restructuring that increases FPEAM's usability and functionality. FPEAM currently estimates emissions of volatile organic compounds, particulate matter, nitrogen oxides, sulfur oxides, and carbon monoxide from on-farm equipment operation, on-farm fugitive dust, on-farm chemical (fertilizer, herbicide and insecticide) application, and biomass transportation. These calculations are implemented within FPEAM as modules, which independently perform calculations for each emissions category. This structure allows users to include or exclude emissions categories according to the goal and scope of their analysis. Each module's input data defines the activities taking place with information including fuel combusted, chemicals applied, and equipment used. Users can replace or augment the default input data to quantify additional pollutant types, emissions categories, farming practices and biomass types. Emissions from biomass transportation and on-farm equipment operation are by default calculated by the U.S. Environmental Protection Agency's Motor Vehicle Emission Simulator (MOVES) and NONROAD model, respectively. These models - which are computationally intensive but provide detailed results - can optionally be replaced with user-provided emissions factors for fuel combustion and vehicle operation. This approach reduces FPEAM's runtime and allows users to run sensitivity analyses around biomass production and transportation scenarios. Other enhancements currently under development are the use of farm-to-biorefinery route information to increase the spatial resolution of transportation emissions, and a module to connect FPEAM and the Intervention Model for Air Pollution (InMAP), which will enable the quantification of human health impacts.

09 BIOMASS FUELS↗
NASA NTRS2015

ESIP Earth Sciences Data Analytics (ESDA) Cluster - Work in Progress

The purpose of this poster is to promote a common understanding of the usefulness of, and activities that pertain to, Data Analytics and more broadly, the Data Scientist; Facilitate collaborations to better understand the cross usage of heterogeneous datasets and to provide accommodating data analytics expertise, now and as the needs evolve into the future; Identify gaps that, once filled, will further collaborative activities. Objectives Provide a forum for Academic discussions that provides ESIP members a better understanding of the various aspects of Earth Science Data Analytics Bring in guest speakers to describe external efforts, and further teach us about the broader use of Data Analytics. Perform activities that:- Compile use cases generated from specific community needs to cross analyze heterogeneous data- Compile sources of analytics tools, in particular, to satisfy the needs of the above data users- Examine gaps between needs and sources- Examine gaps between needs and community expertise- Document specific data analytics expertise needed to perform Earth science data analytics Seek graduate data analytics Data Science student internship opportunities.

science data analysis↗
DOE OSTI2022

The Fourth Catalog of Active Galactic Nuclei Detected by the Fermi Large Area Telescope: Data Release 3

Abstract An incremental version of the fourth catalog of active galactic nuclei (AGNs) detected by the Fermi Large Area Telescope is presented. This version (4LAC-DR3) derives from the third data release of the 4FGL catalog based on 12 yr of E > 50 MeV gamma-ray data, where the spectral parameters, spectral energy distributions (SEDs), yearly light curves, and associations have been updated for all sources. The new reported AGNs include 587 blazar candidates and four radio galaxies. We describe the properties of the new sample and outline changes affecting the previously published one. We also introduce two new parameters in this release, namely the peak energy of the SED high-energy component and the corresponding flux. These parameters allow an assessment of the Compton dominance, the ratio of the inverse-Compton to the synchrotron-peak luminosities, without relying on X-ray data.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2015

IDENTIFICATION OF 1.4 MILLION ACTIVE GALACTIC NUCLEI IN THE MID-INFRARED USING WISE DATA

We present an all-sky sample of ≈1.4 million active galactic nuclei (AGNs) meeting a two-color infrared photometric selection criteria for AGNs as applied to sources from the Wide-field Infrared Survey Explorer final catalog release (AllWISE). We assess the spatial distribution and optical properties of our sample and find that the results are consistent with expectations for AGNs. These sources have a mean density of ≈38 AGNs per square degree on the sky, and their apparent magnitude distribution peaks at g ≈ 20, extending to objects as faint as g ≈ 26. We test the AGN selection criteria against a large sample of optically identified stars and determine the “leakage” (that is, the probability that a star detected in an optical survey will be misidentified as a quasi-stellar object (QSO) in our sample) rate to be ≤4.0 × 10{sup −5}. We conclude that our sample contains almost no optically identified stars (≤0.041%), making this sample highly promising for future celestial reference frame work as it significantly increases the number of all-sky, compact extragalactic objects. We further compare our sample to catalogs of known AGNs/QSOs and find a completeness value of ≳84% (that is, the probability of correctly identifying a known AGN/QSO is at least 84%) for AGNs brighter than a limiting magnitude of R ≲ 19. Our sample includes approximately 1.1 million previously uncataloged AGNs.

79 ASTRONOMY AND ASTROPHYSICS↗
NASA NTRS1986

Activity in F stars

Measurements of He I 5876 A and IUE measurements of chromospheric and transition region lines in a large sample of F-type stars are presented. The data show that activity is detectable in nearly all early F-type stars and differs in several of its characteristics from that typically seen in cooler stars with slow rotation and fully developed convective zones. The onset of activity occurs near B-V = 0.28, which corresponds approximately to spectral type F0 and T(eff) = 7300 K. There is no correlation between the level of activity and the abundances of lithium and beryllium in F stars hotter than T(eff) = 6600 K. All but one of the stars in the 6600-7300 K temperature interval are active. The levels of activity in these stars are independent of Rossby number.

Wolff, Sidney C.↗
DOE OSTI2017

Comparison Of 252 Cf Time Correlated Induced Fisssion With AmLi Induced Fission On Fresh MTR Research Reactor Fuel

The effective application of international safeguards to research reactors requires verification of spent fuel as well as fresh fuel. To accomplish this goal various nondestructive and destructive assay techniques have been developed in the US and around the world. The Advanced Experimental Fuel Counter (AEFC) is a nondestructive assay (NDA) system developed at Los Alamos National Laboratory (LANL) combining both neutron and gamma measurement capabilities. Since spent fuel assemblies are stored in water, the system was designed to be watertight to facilitate underwater measurements by inspectors. The AEFC is comprised of six 3 He detectors as well as a shielded and collimated ion chamber. The 3 He detectors are used for active and passive neutron coincidence counting while the ion chamber is used for gross gamma counting. Active coincidence measurement data is used to measure residual fissile mass, whereas the passive coincidence measurement data along with passive gamma measurement can provide information about burnup, cooling time, and initial enrichment. In the past, most of the active interrogation systems along with the AEFC used an AmLi neutron interrogation source. Owing to the difficulty in obtaining an AmLi source, a 252 Cf spontaneous fission (SF) source was used during a 2014 field trail in Uzbekistan as an alternative. In this study, experiments were performed to calibrate the AEFC instrument and compare use of the 252 Cf spontaneous fission source and the AmLi (α,n) neutron emission source. The 252 Cf source spontaneously emits bursts of time-correlated prompt fission neutrons that thermalize in the water and induce fission in the fuel assembly. The induced fission (IF) neutrons are also time correlated resulting in more correlated neutron detections inside the 3 He detector, which helps reduce the statistical errors in doubles when using the 252 Cf interrogation source instead of the AmLi source. In this work, two MTR fuel assemblies varying both in size and number of fuel plates were measured using 252 Cf and AmLi active interrogation sources. This paper analyzes time correlated induced fission (TCIF) from fresh MTR fuel assemblies due to 252 Cf and AmLi active interrogation sources.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2018

Hanford Site Ecological Monitoring Report for Calendar Year 2017

The U.S. Department of Energy, Richland Operations Office (DOE-RL) conducts ecological monitoring on the Hanford Site to collect and track data needed to ensure compliance with an array of environmental laws, regulations, and policies governing the U.S. Department of Energy’s (DOE) activities. Ecological monitoring data provide baseline information about the plants, animals, and habitats under DOE-RL stewardship at the Hanford Site required for decision making under the National Environmental Policy Act and Comprehensive Environmental Response, Compensation, and Liability Act. DOE/EIS-0222-FU, Final Hanford Comprehensive Land Use Plan Environmental Impact Statement, (CLUP) evaluates potential environmental impacts associated with implementing a comprehensive land use plan for the Hanford Site over the next 50 years. The vision for the DOE-RL-managed portion of the Hanford Site focuses not only on the cleanup of nuclear facilities and waste sites but on the protection of groundwater, the Columbia River, and the restoration of the land for access and use. To reach these goals DOE-RL is working closely with partners, such as the U. S. Fish and Wildlife Service (FWS) and National Park Service, to enable use of the Hanford land consistent with the CLUP. As DOE-RL moves toward accomplishing this vision, monitoring the ecological resources present to determine whether there is a need for conservation and/or protection of any resources will be critical for making informed decisions for responsible site stewardship.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2019

A Parallel Graph Environment for Real-World Data Analytics Workflows

Economic competitiveness and national security depend increasingly on the insightful analysis of large data sets. The diversity of real-world data sources and analytic workflows impose challenging hardware and software requirements for parallel graph platforms. The irregular nature of graph methods is not supported well by the deep memory hierarchies of conventional distributed systems, requiring new processor and runtime system designs to tolerate memory and synchronization latencies. Moreover, the efficiency of relational table operations and matrix computations are not attainable when data is stored in common graph data structures. In this paper, we present HAGGLE, a high-performance, scalable data analytics platform. The platform’s hybrid data model supports a variety of distributed, thread-safe data structures, parallel programming constructs, and persistent and streaming data. An abstract runtime layer enables us to map the stack to conventional, distributed computer systems with accelerators. The runtime uses multithreading, active messages, and data aggregation to hide memory and synchronization latencies on large-scale systems.

Graph Analytics↗
NASA NTRS1987

Critical issues in NASA information systems

The National Aeronautics and Space Administration has developed a globally-distributed complex of earth resources data bases since LANDSAT 1 was launched in 1972. NASA envisages considerable growth in the number, extent, and complexity of such data bases, due to the improvements expected in its remote sensing data rates, and the increasingly multidisciplinary nature of its scientific investigations. Work already has begun on information systems to support multidisciplinary research activities based on data acquired by the space station complex and other space-based and terrestrial sources. In response to a request from NASA's former Associate Administrator for Space Science and Applications, the National Research Council convened a committee in June 1985 to identify the critical issues involving information systems support to space science and applications. The committee has suggested that OSSA address four major information systems issues; centralization of management functions, interoperability of user involvement in the planning and implementation of its programs, and technology.

Source record↗
NASA NTRS1984

Application of MAGSAT to Lithospheric Modeling in South America. Part 2: Synthesis of Geologic and Seismic Data for Development of Integrated Crustal Models

Research activities performed on MAGSAT scalar data over South America, Central America, and the adjacent marine areas are summarized. The geologic utility of magnetic anomalies detected by satellite is demonstrated by focusing on the spherical-Earth interpretation of scalar MAGSAT data in combination with ancillary geological and geophysical data to obtain lithospheric models for these regions related to their contemporary crustal dynamics processes, geologic history, current volcanism seismicity and natural resources.

Keller, G. R.↗