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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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System assessments typically yield large quantities of data from disparate sources for an analyst to scrutinize for issues. Netmeld is used to parse input from different file formats, store the data in a common format, allow users to easily query it, and enable analysts to tie different analysis tools together using a common back-end.
Data from Advanced Laboratory and Field Arrays (ALFA) Non-linear Ocean Waves and Power Take-Off (PTO). Control Strategy project conducted at the O.H. Hinsdale Wave Research Laboratory (HWRL) at Oregon State University in 2019/2020. Contains two zip files (ALFANL.zip, ALFANL2.zip) from two phases of testing with data in engineering units and a report detailing the testing. This data collected by HWRL. A readme file in the docs folder explains the data collection and format. Six zip files (foswec-1 to foswec-6) data recorded by the Floating Oscillating Surge Wave Energy Converter (FOSWEC). Data organized by date and time and report describes data. A test report (ALFA Non-linear Ocean Waves Test Report.docx) details the experiments and data recording.
This dataset describing the responses of plant and soil pools and fluxes to elevated atmospheric CO2 concentration and increased nitrogen supply was collected from Duke Forest Free Air CO2 Enrichment (FACE) – Forest-Atmosphere Carbon Transfer and Storage (FACTS-I) experiment from 1996 to 2012. The dataset includes data files for allometry (diameter at breast height, tree height, and height to live crown base), leaf area index, biomass (stem, branch, foliage, and root biomass, tree density, and basal area), net primary productivity (stem, branch, foliage, reproductive, and coarse root NPP), sap flux density, soil CO2 efflux, and stem temperature. Data files were formatted as .csv (Microsoft Excel or other spreadsheet programs can be used to read the format) and file descriptions, including variable name, unit, and data range, can be found in ‘FileDescription_[data_name].txt’ files. The Duke FACE experiment was in a loblolly pine (Pinus taeda L.) plantation established in 1983. Naturally regenerated broadleaved species including sweetgum (Liquidambar styraciflua L.) and tulip poplar (Liriodendron tulipifera L.), mostly in the overstory, and winged elm (Ulmus alata Michx.) and red maple (Acer rubrum L.) were common in the understory. The FACE experiment commenced with two plots (plots 7-8) in 1994 (Oren et al. 2001), with six additional plots (plots 1-6) coming online on 27 August 1996. CO2 enrichment was terminated on 31 October 2010 and post-enrichment data collection continued through 2012. Complete fertilization was applied annually to half of plots 7-8 from 1998 to 2004. The nutrient addition experiment expanded to half of plots 1-6 with a common protocol of N-fertilization in 2005 and continued until 2012. The levels of treatment in this dataset were expressed as ambient CO2 (AMB) or elevated CO2 (ELE) for CO2 treatment and control soil (CONT) or fertilized soil (FERT) for N treatment, respectively.
The objective of the Nuclear Criticality Safety Program (NCSP) Analytical Methods program element is to sustain state-of-the-art radiation transport modeling capabilities and the expertise necessary to develop, maintain, and disseminate the analytical tools and data libraries in a manner that is responsive to the needs of those responsible for developing, implementing, and maintaining criticality safety. To this end, the objective of the AMPX Development and Maintenance Subtask is to ensure that the AMPX cross-section processing system is available to prepare cross-section and covariance libraries that are needed by SCALE and other radiation transport packages to support criticality safety analyses of systems with fissionable material. Moreover, the task ensures that the cross-section processing software is current and up-to-date with the Evaluated Nuclear Data File (ENDF/B) formats and procedures for disseminating evaluated cross-section data provided through new measurement and evaluation work efforts. The AMPX subtask provides for the production of data libraries needed for criticality safety analyses. As such, the task provides the “bridge” between the nuclear data evaluations and the radiation transport software. In the absence of the AMPX cross-section processing task, the ability to maintain and update the SCALE nuclear data libraries (cross-section and covariance data) would be hindered. Therefore, the AMPX Development and Maintenance Subtask ensures that SCALE is up-to-date with the latest cross-section data for supporting criticality safety analyses. This letter report provides a summary of the FY 2015 AMPX development and maintenance activities that have been performed in support of the NCSP. Specifically, the report summarizes the AMPX code system updates and modernization accomplishments that have been made to the software package. Also, the report documents the cross-section library updates that have been made for the SCALE radiation transport package. In addition, the report documents testing activities that have been performed to process available cross-section and covariance data files to ensure the latest ENDF/B data files can be processed properly. This report satisfies the following reporting milestone in the NCSP FY16-20 Five Year Plan: Document AMPX modernization and technical support for SCALE continuous energy (CE), multigroup (MG), and covariance libraries and report status annually to the NCSP Manager (AM3: Q2)
Thermal neutron scattering law (TNSL) data describe low-energy neutrons scattering off of bound materials, and can have a significant impact on modeling any system with slow neutrons, including nuclear reactors. Previous work to introduce TNSL data to neutron transport codes at LLNL focused on COG and TART [1], with the limitation that these codes require highly specialized data processing and formatting. We have recently increased efforts to process TNSL data with the central LLNL nuclear data processing code FUDGE, to be stored in the generalized nuclear database structure (GNDS) for use in any general transport code with the ability to read GNDS data. The first step in this effort is to verify that the TNSL processing with FUDGE yields results comparable to results obtained using the LANL nuclear data processing code NJOY. The next step is to verify the transport of thermal neutrons in Mercury (a Monte Carlo code) and Ardra (a deterministic code) against one another, as well as against the LANL Monte Carlo neutron transport code MCNP. This verification step has not been completed, due to a number of discrepancies between results obtained using differently processed data. There is ongoing effort to understand differences between FUDGE and NJOY. Finally, we map out our current capability to validate TNSL data against benchmark systems.
Developed by the Pacific Northwest National Laboratory (PNNL), the Geospatial Risk Analysis Tool (GRAT) links to Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT), a complete system for computing simple air parcel trajectories, as well as complex transport, dispersion, chemical transformation, and deposition simulations. The HYSPLIT model was developed by the National Oceanic and Atmospheric Administration (NOAA) Air Resources Laboratory and the Australian Bureau of Meteorology Research Center in 1998. GRAT is used to batch process meteorological data into ARL format. While HYSPLIT GUI limits users to convert meteorological data up to 6 date time points per operation, GRAT enables users to convert a significantly large amount of data (For example, 10 years of meteorological data measured with an interval of 5 minutes) within one operation. Incorporated with the Potential source distribution function (PSDF), GRAT can also be used to determine the areas influenced by the emission of hazardous chemicals.
The U.S. Environmental Protection Agency (USEPA) provides databases that agglomerate data provided by companies or states reporting emissions, releases, wastes generated, and other activities to meet statutory requirements. These databases, often referred to as inventories, can be used for a wide variety of environmental reporting and modeling purposes to characterize conditions in the United States. Yet, users are often challenged to find, retrieve, and interpret these data due to the unique schemes employed for data management, which could result in erroneous estimations or double-counting of emissions. To address these challenges, a system called Standardized Emission and Waste Inventories (StEWI) has been created. The system consists of four python modules that provide rapid access to USEPA inventory data in standard formats and permit filtering and combination of these inventory data. When accessed through StEWI, reported emissions of carbon dioxide to air and ammonia to water are reduced approximately two- and four-fold, respectively, to avoid duplicate reporting. StEWI will greatly facilitate the use of USEPA inventory data in chemical release and exposure modeling and life cycle assessment tools, among other things. To date, StEWI has been used to build the recent USEEIO model and the baseline electricity life cycle inventory database for the Federal LCA Commons.
The Station Data Acquisition and Control System (STADAC), a multicomputer data handling and control system, is expected to be installed in six network stations, the first station to be established at Goddard Space Flight Center. Network control data, in the form of schedules and acquisition pointing data, flow from the Network Control Center to the stations, while station status data flow in the other direction. The system will format spacecraft telemetry data for real-time transmission of control and status data to the project operations control centers and for transmission of experiment data to the data processing facilities. The system will also schedule station equipment resources, perform prepass tests to assure data quality, and automatically set up selected station equipment.
This paper describes the Telemetry Computer System in operation at NASA's Wallops Flight Center for real-time or off-line processing, storage, and display of telemetry data from rockets and aircraft. The system accepts one or two PCM data streams and one FM multiplex, converting each type of data into computer format and merging time-of-day information. A data compressor merges the active streams, and removes redundant data if desired. Dual minicomputers process data for display, while storing information on computer tape for further processing. Real-time displays are located at the station, at the rocket launch control center, and in the aircraft control tower. The system is set up and run by standard telemetry software under control of engineers and technicians. Expansion capability is built into the system to take care of possible future requirements.
The objective and contribution of the research presented in this paper is to provide a Multi-Mode Manipulator Display System (MMDS) to assist a human operator with the control of remote manipulator systems. Such systems include space based manipulators such as the space shuttle remote manipulator system (SRMS) and future ground controlled teleoperated and telescience space systems. The MMDS contains a number of display modes and submodes which display position control cues position data in graphical formats, based primarily on manipulator position and joint angle data. Therefore the MMDS is not dependent on visual information for input and can assist the operator especially when visual feedback is inadequate. This paper provides descriptions of the new modes and experiment results to date.
In recent years, morphometric data for Venus and several outer planet satellites have been collected, so we now have observational data of complex Craters formed in a large range of target properties. We present general inversion techniques that can utilize the morphometric data to quantitatively test various models of complex crater formation. The morphometric data we use in this paper are depth of a complex crater, the diameter at which the depth-diameter ratio changes, and onset diameters for central peaks, terraces, and peak rings. We tested the roles of impactor velocities and hydrostatic pressure vs. crustal strength, and we tested the specific models of acoustic fluidization (Melosh, 1982) and nonproportional growth (Schultz, 1988). Neither the acoustic fluidization model nor the nonproportional growth in their published formulations are able to successfully reproduce the data. No dependence on impactor velocity is evident from our inversions. Most of the morphometric data is consistent with a linear dependence on the ratio of crustal strength to hydrostatic pressure on a planet, or the factor c/pg.
Observation of linear contrail cirrus coverage and retrieval of their optical properties are valuable data for validating atmospheric climate models that represent contrail formation explicitly. These data can reduce our uncertainty of the regional effects of contrail-generated cirrus on global radiative forcing, and thus improve our estimation of the impact of commercial aviation on climate change. We use an automated contrail detection algorithm (CDA) to determine the coverage of linear persistent contrails over the Northern Hemisphere during 2012. The contrail detection algorithm is a modified form of the Mannstein et al. (1999) method, and uses several channels from thermal infrared MODIS data to reduce the occurrence of false positive detections. A set of contrail masks of varying sensitivity is produced to define the potential range of uncertainty in contrail coverage estimated by the CDA. Global aircraft emissions waypoint data provided by FAA allow comparison of detected contrails with commercial aircraft flight tracks. A pixel-level product based on the advected flight tracks defined by the waypoint data and U-V wind component profiles from the NASA GMAO GEOS-4 reanalysis has been developed to assign a confidence of contrail detection for the contrail mask. To account for possible contrail cirrus missed by the CDA, a post-processing method based on the assumption that pixels adjacent to detected linear contrails will have radiative signatures similar to those of the detected contrails is applied to the Northern Hemisphere data. Results from several months of MODIS observations during 2012 will be presented, representing a near-global climatology of contrail coverage. Linear contrail coverage will be compared with coverage estimates determined previously from 2006 MODIS data.
Since the launch of Terra satellite in 1999, the number of Earth Science remote sensing data products created and distributed by NASA's Earth Observing System (EOS) Data and Information System (EOSDIS) has increased from a few hundred to nearly ten thousand. NASA's Earth Science Data and Information System (ESDIS) Metrics System (EMS) collects metrics on data ingest, archive, and distribution by its Distributed Active Archive Centers (DAACs) and the Science Investigator-led Systems (SIPS), known as Data Providers. These metrics are critical in helping NASA management as well as data producers in resource planning and gaining a wide range of knowledge of data users and data usage.EMS receives flat files, or log files of data archive, ingest, and distribution either in their raw format, such as Apache web logs, or text files of log records formatted by the Data Providers. Tens of millions of records are processed each day to extract metrics on data products, user information, distribution protocols and services, and so on. The metrics are then made available to designated parties.This presentation provides an overview of the EMS processing workflow and improvement efforts made in recent years to handle ever-increasing number of data records and new metrics requirements, discusses several key steps including mapping log records to data products and identifying user communities along with geo-distribution, and demonstrates typical metrics capabilities produced by the EMS system. Challenges and potential approaches to improve the system are also discussed.
Thermal neutron scattering law (TNSL) data describe low-energy neutrons scattering off of bound materials, and can have a significant impact on modeling any system with slow neutrons, including nuclear reactors. Previous work to introduce TNSL data to neutron transport codes at LLNL focused on COG and TART, with the limitation that these codes require highly specialized data processing and formatting. We have recently increased efforts to process TNSL data with the LLNL nuclear data processing code FUDGE. FUDGE reads and writes the evaluated and processed files using the generalized nuclear database structure (GNDS). This process uncovered some significant difficulties in processing TNSL data, and unearthed assumptions made in current TNSL data processing that we have found inadequate. (authors)
We present experimental data regarding the formation of high-energy-density shocks in magnetically accelerated plasma flows using pulsed power drivers. We quantify the flow velocity and temperature of the ablated plasma using optical Thomson scattering and gated emission imaging across two different generators. We show that, regardless of the drive parameters, the plasma flows show continuous acceleration over centimeter spatial scales, in line with trends in published simulation work. When stationary targets are placed in these supersonic flows, bow-shock formation is observed at all drive parameters in a range of materials. In the higher density flow generated on the 1-MA COBRA generator at Cornell University, heating of the upstream flow ahead of the shock is observed and quantified, which is not observed at the lower density flow on the 0.2-MA Bertha driver at UC San Diego. Here, when combined with previous work on the XP generator at Cornell, we can show that these three experimental setups allow control of the effect of radiation loss and upstream absorption on the formation of the bow shock.
The programs described were developed to process GEODYN-formatted satellite altimeter data, and to apply the processed results to predict geoid undulations and gravity anomalies of inland sea areas. These programs are written in standard FORTRAN 77 and are designed to run on the NSESCC IBM 3081(MVS) computer. Because of the experimental nature of these programs they are tailored to the geographical area analyzed. The attached program listings are customized for processing the altimeter data over the Black Sea. Users interested in the Caspian Sea data are expected to modify each program, although the required modifications are generally minor. Program control parameters are defined in the programs via PARAMETER statements and/or DATA statements. Other auxiliary parameters, such as labels, are hard-wired into the programs. Large data files are read in or written out through different input or output units. The program listings of these programs are accompanied by sample IBM job control language (JCL) images. Familiarity with IBM JCL and the TEMPLATE graphic package is assumed.
The Kepler space mission searches its time series data for periodic, transit-like signatures. The ephemerides of these events, called Threshold Crossing Events (TCEs), are reported in the TCE tables at the NASA Exoplanet Archive (NExScI). Those TCEs are then further evaluated to create planet candidates and populate the Kepler Objects of Interest (KOI) table, also hosted at the Exoplanet Archive. The search, evaluation and export of TCEs is performed by two pipeline modules, TPS (Transit Planet Search) and DV (Data Validation). TPS searches for the strongest, believable signal and then sends that information to DV to fit a transit model, compute various statistics, and remove the transit events so that the light curve can be searched for other TCEs. More on how this search is done and on the creation of the TCE table can be found in Tenenbaum et al. (2012), Seader et al. (2015), Jenkins (2002). For each star with at least one TCE, the pipeline exports a file that contains the light curves used by TPS and DV to find and evaluate the TCE(s). This document describes the content of these DV time series files, and this introduction provides a bit of context for how the data in these files are used by the pipeline.
The major task of this work has been to collect, document, and translate a wide variety of occultation data sets to a common format. This work has been completed. Table I lists the 1977-1987 Uranus occultation data sets that have been retrieved and which are ready for conversion to the PDS occultation standard format, once it has been standardized. The primary documentation and original data tapes for these occultations are part of the MIT data archive, and will be submitted to the PDS from MIT. I have been in contact with Jim Elliot and Steve McDonald, who are carrying out this work, and they have informed me that some of the original data tapes have bad blocks in them. As called upon, I will continue to provide the MIT group with whatever information they require in order that the most complete versions of the data sets be provided to the PDS. 2. All data sets from MIT NOVA disk platters were transcribed to Exabyte tapes, and software was written to enable the NOVA binary data formats to be converted to IEEE standard format. The number of these files which will be contributed to the PDS will depend on the success of the MIT group in reading the original data tapes for the events recorded on these disk platters. As needed, I will supply the MIT group with translated versions of these salvaged files for submission to the PDS. 3. The imaging observations from McDonald and Lick Observatories have been calibrated in both radius and optical depth, and are available in simple binary format. 4. Final submission of the Uranus ring data sets to the PDS is awaiting final agreement by the Rings Node Advisory Council on the PDS FITS format to be adopted for occultation data set.