AndreaBozzo/ceres-open-data-index huggingface dataset:
Diagnosing Faults in Electrical Power Systems of Spacecraft and Aircraft

Electrical power systems play a critical role in spacecraft
and aircraft, and they exhibit a rich variety of failure modes.
This paper discusses electrical power system fault diagnosis
by means of probabilistic techniques. Specically, we discuss
our development of a diagnostic capability for an electrical
power system testbed, ADAPT, located at NASA Ames.
We emphasize how we have tackled two challenges, regarding
modelling and real-time performance, often encountered
when developing diagnostic applications. We carefully discuss
our Bayesian network modeling approach for electrical
power systems. To achieve real-time performance, we build
on recent theoretically well-founded developments that compile
a Bayesian network into an arithmetic circuit. Arithmetic
circuits have low footprint and are optimized for embedded,
real-time systems such as spacecraft and aircraft.
We discuss our probabilistic diagnostic models developed for
ADAPT along with successful experimental results.

Tags: ames, dashlink, nasa
Organization: National Aeronautics and Space Administration
TRMM Ground Validation Radar Site Rain Type Totals Map L3 1 month 2 km V7 (TRMM_3A54) at GES DISC

The 3A54 product, 'Site Rainfall Map', is a map of monthly surface rain totals derived from the instantaneous rain rate maps (2A53). The map is in Cartesian coordinates with a 2 km horizontal resolution and covers an area of 300km x 300km at single radar sites while the covered area varies for multiple radar sites - 724 km x 568 km at Texas site and 512 km x 704 km at Florida site. This monthly rainfall map is not a simple accumulation of the instantaneous maps as gaps in the data must be factored into the calculation. 

A key component of the TRMM project is the Ground Validation (GV) effort which consists of collecting data from ground-based radar, rain gauges and disdrometers. The data is quality-controlled, and then validation products are produced for comparison with TRMM satellite products.

The four primary GV sites are:

+ Darwin, Australia; 
+ Houston, Texas; 
+ Kwajalein, Republic of the Marshall Islands;
+ Melbourne, Florida. 

A significant effort is also being supported at NASA Wallops Flight Facility (WFF) and vicinity to provide high quality, long-term measurements of rain rates (via a network of rain gauges collocated with National Weather Service gauges), as well as drop size distributions (DSD) using a variety of instruments, including impact-type Joss Waldvogel, laser-optical Parsivel, as well as two-dimensional video disdrometers.  DSD measurements are also being collected at Melbourne and Kwajalein using Joss-Waldvogel disdrometers.

Tags: atmosphere, earth-science, precipitation, radar, spectral-engineering
Organization: National Aeronautics and Space Administration
EnviroAtlas - Philadelphia, PA - Park Access by Block Group

This EnviroAtlas dataset shows the block group population that is within and beyond an easy walking distance (500m) of a park entrance. Park entrances were included in this analysis if they were within 5km of the EnviroAtlas community boundary. This dataset was produced by the US EPA to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. The dataset is available as downloadable data (https://edg.epa.gov/data/Public/ORD/EnviroAtlas) or as an EnviroAtlas map service. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets).

Tags: census block groups, communities, ecosystem, ecosystem services, enviroatlas, environment, environmental atlas, human well-being, pa, pennsylvania, philadelphia, recreation
Organization: U.S. Environmental Protection Agency
High-Resolution Radar Imagery, Digital Elevation Models, and Related GIS Layers for Barrow, Alaska, USA, Version 1

This product set contains high-resolution Interferometric Synthetic Aperture Radar (IFSAR) imagery and geospatial data for the Barrow Peninsula (155.39 - 157.48 deg W, 70.86 - 71.47 deg N) and Barrow Triangle (156.13 - 157.08 deg W, 71.14 - 71.42 deg N), for use in Geographic Information Systems (GIS) and remote sensing software. The primary IFSAR data sets were acquired by Intermap Technologies from 27 to 29 July 2002, and consist of Orthorectified Radar Imagery (ORRI), a Digital Surface Model (DSM), and a Digital Terrain Model (DTM).

Derived data layers include aspect, shaded relief, and slope-angle grids (floating-point binary and ArcInfo grid format), as well as a vector layer of contour lines (ESRI Shapefile format). Also available are accessory layers compiled from other sources: 1:250,000- and 1:63,360-scale USGS Digital Raster Graphic (DRG) mosaic images (GeoTIFF format); 1:250,000- and 1:63,360-scale USGS quadrangle index maps (ESRI Shapefile format); a quarter-quadrangle index map for the 26 IFSAR tiles (ESRI Shapefile format); and a simple polygon layer of the extent of the Barrow Peninsula (ESRI Shapefile format).

Unmodified IFSAR data comprise 26 data tiles across UTM zones 4 and 5. The DSM and DTM tiles (5 m resolution) are provided in floating-point binary format with header and projection files. The ORRI tiles (1.25 m resolution) are available in GeoTIFF format. FGDC-compliant metadata for all data sets are provided in text, HTML, and XML formats, along with the Intermap License Agreement and product handbook. 

The baseline geospatial data support education, outreach, and multi-disciplinary research of environmental change in Barrow, which is an area of focused scientific interest.

Data are provided on five DVDs, available through licensing only to National Science Foundation (NSF)-funded investigators. An NSF award number must be provided when ordering data.

Tags: earth-science, land-surface, radar, spectral-engineering, topography
Organization: National Aeronautics and Space Administration
Distributed Prognostics Based on Structural Model Decomposition

Within systems health management, prognostics focuses on predicting the remaining useful life of a system. In the model-based prognostics paradigm, physics-based models are constructed that describe the operation of a system, and how it fails. Such approaches consist of an estimation phase, in which the health state of the system is first identified, and a prediction phase, in which the health state is projected forward in time to determine the end of life. Centralized solutions to these problems are often computationally expensive, do not scale well as the size of the system grows, and introduce a single point of failure. In this paper, we propose a novel distributed model-based prognostics scheme that formally describes how to decompose both the estimation and prediction problems into computationally-independent local subproblems whose solutions may be easily composed into a global solution. The decomposition of the prognostics problem is achieved through structural decomposition of the underlying models. The decomposition algorithm creates from the global system model a set of local submodels suitable for prognostics. Computationally independent local estimation and prediction problems are formed based on these local submodels, resulting in a scalable distributed prognostics approach that allows the local subproblems to be solved in parallel, thus offering increases in computational efficiency. Using a centrifugal pump as a case study, we perform a number of simulation-based experiments to demonstrate the distributed approach, compare the performance with a centralized approach, and establish its scalability.

Tags: ames, dashlink, nasa
Organization: National Aeronautics and Space Administration
TRMM Ground Validation Radar Site Rain Type Totals Map L3 1 month 2 km V7 (TRMM_3A54UW) at GES DISC

This dataset is part of the University of Washington TRMM Ground Validation products.

Monthly rain accumulation cartesian grid based on 2A53UW. Units are mm. Min range is 17 km, max range is 150 km. Horizontal extent is 150x150km and resolution is 2km. Note that in the netCDF files, "alt" (altitude) is assigned the elevation angle of the lowest sweep (which is used to create baseUW) and "z_spacing" has no meaning.

A key component of the TRMM project is the Ground Validation (GV) effort which consists of collecting data from ground-based radar, rain gauges and disdrometers. The data is quality-controlled, and then validation products are produced for comparison with TRMM satellite products.

The four primary GV sites are:

+ Darwin, Australia; 
+ Houston, Texas; 
+ Kwajalein, Republic of the Marshall Islands;
+ Melbourne, Florida. 

A significant effort is also being supported at NASA Wallops Flight Facility (WFF) and vicinity to provide high quality, long-term measurements of rain rates (via a network of rain gauges collocated with National Weather Service gauges), as well as drop size distributions (DSD) using a variety of instruments, including impact-type Joss Waldvogel, laser-optical Parsivel, as well as two-dimensional video disdrometers.  DSD measurements are also being collected at Melbourne and Kwajalein using Joss-Waldvogel disdrometers.

Tags: atmosphere, earth-science, precipitation, radar, spectral-engineering
Organization: National Aeronautics and Space Administration
Ensemble Approach to Building Mercer Kernels

This paper presents a new methodology for automatic knowledge driven data mining based on the theory of Mercer Kernels, which are highly nonlinear symmetric positive definite mappings from the original image space to a very high, possibly infinite dimensional feature space. We describe a new method called Mixture Density Mercer Kernels (MDMK) to learn kernel function directly from data, rather than using pre-defined kernels. These data adaptive kernels can encode prior knowledge in the kernel using a Bayesian formulation, thus allowing for physical information to be encoded in the model. Specifically, we demonstrate the use of the algorithm in situations with extremely small samples of data. We compare the results with existing algorithms on data from the Sloan Digital Sky Survey (SDSS) and demonstrate the method’s superior performance against standard methods. The results show that the Mixture Density Mercer Kernel described here outperforms tree-based classification in distinguishing high-redshift galaxies from low redshift galaxies by approximately 16% on test data, bagged trees by approximately 7%, and bagged trees built on a much larger sample of data by approximately 2%. The code for these experiments has been generated with the AutoBayes tool, which automatically generates efficient and documented C/C++ code from abstract statistical model specifications. The core of the system is a schema library which contains templates for learning and knowledge discovery algorithms like different versions of EM, or numeric optimization methods like conjugate gradient methods. The template instantiation is supported by symbolic algebraic computations, which allows AutoBayes to find closed form solutions and, where possible, to integrate them into the code.

Tags: ames, dashlink, nasa
Organization: National Aeronautics and Space Administration
Ground-Based Global Navigation Satellite System (GNSS) GPS real-time POD Clock Corrections  (1-second sampling, 60-second files) from NASA CDDIS

This product contains a high-rate time series of clock biases for healthy satellites in the GPS constellation that are accumulated every minute throughout the day. In addition, formal 1-sigma uncertainties for the corrections are provided. The product is generated at JPL's Global Differential GPS Operations Centers in real-time. The data in this product can be concatenated with other daily products to provide larger coverage in time.

Tags: earth-science, geodetics, gravity-gravitational-field, solid-earth, tectonics
Organization: National Aeronautics and Space Administration
CASES

The CASES program was carried out from September 2002 to August 2004. The objective of the CASES field expeditions was to perform an extensive sampling of the Southern Beaufort Sea and the Amundsen Gulf coastal shelves (from 67N to 76N and from 120W to 41W). Two different expeditions were held. The first expedition was conducted on board the CCGS Pierre Radisson between September 20th and October 14th, 2002 and was identified as leg 0. The second expedition was conducted on board the CCGS Amundsen between September 8th, 2003, and August 26th, 2004. This last expedition was divided into nine periods of six weeks (four weeks for leg 9) designated legs 1 to 9.<br>The scientific program is focussing on a central hypothesis which states that the atmospheric, oceanic and hydrologic forcing of sea ice variability dictates the nature and magnitude of biogeochemical carbon fluxes on and at the edge of the Mackenzie Shelf. The Canadian-led projects studied: 1) Atmospheric and sea ice forcing of coastal circulation; 2) Ice-atmosphere interactions and biological linkages; 3) Light, nutrients, primary and export production in ice-free waters; 4) Microbial communities and heterotrophy; 5) Pelagic food web: structure, function and contaminants; 6) Organic and inorganic fluxes; 7) Benthic processes and carbon cycling; 8) Millennial-decadal variability in sea ice and carbon fluxes; 9) Coupled bio-physical models of the carbon flows on the Canadian Arctic Shelf (Simard et al., 2010).<br>Reference: Simard, A., Rail, M.E., Gratton, Y. 2010. Distribution of temperature and salinity in the Beaufort Sea during the Canadian Arctic Shelf Exchange Study sampling expeditions 2002-2004. Report No R1187, INRS-ETE, Quebec (QC), 128p.

Tags: earth-science, ocean-chemistry, ocean-optics, ocean-temperature, oceans, salinity-density
Organization: National Aeronautics and Space Administration
Suomi-NPP VIIRS Level-3 Global Binned Triple-window Sea Surface Temperature (SST3) - Near Real-time (NRT) Data, version R2016.2

The Ocean Biology DAAC produces near real-time (quicklook) products using the best-available combination of ancillary data from meteorological and ozone data. As such, the inputs and the calibration used are less than optimal. Quicklook products provide a snapshot of the data during a short time period within a single orbit.

Tags: earth-science, ocean-temperature, oceans
Organization: National Aeronautics and Space Administration
SWOT Level 2 Lake Single-Pass Vector Unassigned Data Product, Version 2.0

The SWOT Level 2 Lake Single-Pass Vector Unassigned Data Product from the Surface Water Ocean Topography (SWOT) mission provides water surface elevation, area, storage change derived from the high rate (HR) data stream from the Ka-band Radar Interferometer (KaRIn). SWOT launched on December 16, 2022 from Vandenberg Air Force Base in California into a 1-day repeat orbit for the "calibration" or "fast-sampling" phase of the mission, which completed in early July 2023. After the calibration phase, SWOT entered a 21-day repeat orbit in August 2023 to start the "science" phase of the mission, which is expected to continue through 2025. <br> Water surface elevation, area, and storage change are provided in three feature datasets covering the full swath for each continent-pass: 1) an observation-oriented feature dataset of lakes identified in the prior lake database (PLD), 2) a feature dataset of lakes identified in the PLD, and 3) a feature dataset containing unassigned features (i.e., not identified in PLD nor prior river database (PRD)). These data are generally produced for inland and coastal hydrology surfaces, as controlled by the reloadable KaRIn HR mask. The dataset is distributed in ESRI Shapefile format. <br> This collection is a sub-collection of its parent: https://podaac.jpl.nasa.gov/dataset/SWOT_L2_HR_LakeSP_2.0 It contains feature datasets of unassigned water features that were not identified in the PLD or PRD.

Tags: earth-science, surface-water, terrestrial-hydrosphere
Organization: National Aeronautics and Space Administration
OCO-3 Level 1B calibrated, geolocated calibration spectra,  V10 (OCO3_L1B_Calibration) at GES DISC

Version 10 is the current version of the data set. Older versions will no longer be available and are superseded by Version 10.

The Orbiting Carbon Observatory -3 (OCO-3) was deployed to the International Space Station in May, 2019. It is technically a single instrument, almost identical to OCO-2.

The Orbiting Carbon Observatory is the first NASA mission designed to collect space-based measurements of atmospheric carbon dioxide with the precision, resolution, and coverage needed to characterize the processes controlling its buildup in the atmosphere. 

The OCO-3 incorporates three high-resolution spectrometers that make coincident measurements of reflected sunlight in the near-infrared CO2 near 1.61 and 2.06 micrometers and in molecular oxygen (O2) A-Band at 0.76 micrometers. The three spectrometers have different characteristics and are calibrated independently. Their raw data numbers (DN) are delivered correlated in time to the Level 1B process as Level 1A products. Each band has 1016 spectralelements, although some are masked out in the L2 retrieval.

This L1B product results from calibration mode measurements (e.g., Lunar,Solar, Dark observations), and thus it differs from the OCO3_L1B_Science (L1bSc) product. The differences in the product formats are only in the geolocation information provided. Whereas the L1bSc products report geolocation data for each sounding, calibration products report the direction of the boresight vector.

Tags: atmosphere, atmospheric-chemistry, earth-science, infrared-wavelengths, spectral-engineering
Organization: National Aeronautics and Space Administration
USGS Antarctic Single Frame Records

Antarctic Single Frame Records are a collection of aerial photographs over Antarctica from the United States Antarctic Resource Center (USARC) and the British Antarctic Survey (BAS) dating from 1946 to 2000. The Antarctic Single Frame Records collection includes black-and-white, natural color and color infrared images with a photographic scale ranging from 1:1,000 to 1:64,000.

Tags: earth-science, land-surface, surface-radiative-properties, topography
Organization: National Aeronautics and Space Administration
High Mountain Asia Daily 5 km Downscaled SPEAR Precipitation and Air Temperature Projections V001

This data set consists of daily, 5 km resolution precipitation and mean, near-surface air temperature projections from 2015 through 2100 for the High Mountain Asia (HMA) region. The data were generated by statistically downscaling 0.5° resolution model data from the Geophysical Fluid Dynamic Laboratory (GFDL) Seamless System for Prediction and EArth System Research (SPEAR) 30-member ensemble climate model.

Projections are provided for two Shared Socioeconomic Pathways (SSPs): SSP2-4.5 and SSP5 8.5. The historical model run (1990 through 2014) used to initialize the SPEAR projections is also available.

Tags: atmosphere, atmospheric-temperature, earth-science, precipitation
Organization: National Aeronautics and Space Administration
Towards a Framework for Evaluating and Comparing Diagnosis Algorithms

Diagnostic inference involves the detection of anomalous system behavior and the identification of its cause, possibly down to a failed unit or to a parameter of a failed unit. Traditional approaches to solving this problem include expert/rule-based, model-based, and data-driven methods. Each approach (and various techniques within each approach) use different representations of the knowledge required to perform the diagnosis. The sensor data is expected to be combined with these internal representations to produce the diagnosis result. In spite of the availability of various diagnosis technologies, there have been only minimal efforts to develop a standardized software framework to run, evaluate, and compare different diagnosis technologies on the same system. This paper presents a framework that defines a standardized representation of the system knowledge, the sensor data, and the form of the diagnosis results – and provides a run-time architecture that can execute diagnosis algorithms, send sensor data to the algorithms at appropriate time steps from a variety of sources (including the actual physical system), and collect resulting diagnoses. We also define a set of metrics that can be used to evaluate and compare the performance of the algorithms, and provide software to calculate the metrics.

Tags: ames, dashlink, nasa
Organization: National Aeronautics and Space Administration
Aging Methodologies and Prognostic Health Management for Electrolytic Capacitors

Understanding the ageing mechanisms of electronic components critical avionics systems such as the GPS and INAV are of critical importance. Electrolytic capacitors and MOSFET’s have higher failure rates among the components of DC-DC power converter systems. Our current work focuses on analyzing and modeling electrolytic capacitor degradation and its effects on the output of DC-DC converter systems. The output degrada- tion is typically measured by an increase in ESR (Equivalent Series Resistance) and decrease in the capacitance value over long periods of use even under nominal operating conditions. Typically the primary effect of degradation is increased ripple current and this has adverse effects on downstream components. For example, in avionics systems where the power supply drives a GPS unit, ripple currents can cause glitches in the GPS position and velocity output, and this may cause errors in the Inertial Navigation (INAV) system, causing the aircraft to fly off course. In this paper, we present the details of our ageing methodology along with details of experiments and analysis of the results.

Tags: ames, dashlink, nasa
Organization: National Aeronautics and Space Administration
DXC'11 Framework and Oracle

The DXC Framework is a collection of programs and APIs for running and evaluating diagnostic algorithms (DAs) under identical experimental conditions. It is complementary to system XML catalogs and data sets.

The Oracle for DXC'11 is the same as DXC'10 and provides a querying capability to the DAs to determine the correct actions for given faults. Because the Oracle uses proprietary NASA software, it is provided only in binary form. Thus the framework is available as a windows binary installer, linux source files + binary oracle, or windows source files + binary oracle. Please see the included READMEs and example DAs for more information.

Tags: ames, dashlink, nasa
Organization: National Aeronautics and Space Administration