Search NASA⌕ Search

SEARCH · Search NASA

Results for “DAY”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 577 records · Page 32
All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

DOE Data Days (Q2 FY2022 Report)

During the FY22Q2 the DOE Data Days planning committee continued to work on the workshop agenda. The following are high-level accomplishments: • Selected four themes for poster and oral presentations to cover in the DOE Data Workshop • Developed a list of potential invited speakers, 1 per theme with an alternate as well • Adapted existing plans to accommodate a hybrid workshop instead of virtual including booking location • Sent out Save The Dates for the workshop • Sent out Call for Abstracts that are currently open.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2022

DOE Data Days 2022 Report

The DOE Data Days (D3) workshop brings together data managers, developers, researchers, and program managers across the Department of Energy (DOE) and national laboratories to highlight data management successes, identify potential synergies and common problems, and establish channels for collaboration across the DOE data management community.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2024

DOE Data Days 2023 Report

The DOE Data Days (D3) workshop brings together data managers, developers, researchers, and program managers across the Department of Energy (DOE) and national laboratories to highlight data management successes, identify potential synergies and common problems, and establish channels for collaboration across the DOE data management community. The fourth D3 workshop was held on October 24th to 26th, 2023 held entirely in-person at Lawrence Livermore National Laboratory (LLNL). The workshop was organized by a multi laboratory committee in an effort to bring data management practitioners at the DOE laboratories together to share their work and results, facilitating knowledge transfers and best practices across project teams. Tools and platforms to support data management and analysis are rapidly evolving and provide enormous opportunities. This report summarizes the important discussions and recommendations from the different working sessions and contains the agenda, submitted abstracts, presentations with links to recorded presentations, breakout session summaries, list of registered attendees, and lessons learned for future organizing committee. The report will be distributed to the DOE, each participating institution’s programmatic stakeholders, and attendees. The dedicated D3 website will host presentations, agenda, and report that is accessible by all labs.

96 KNOWLEDGE MANAGEMENT AND PRESERVATION↗
DOE OSTI2025

Day-Ahead Probabilistic Forecasting of Net-Load and Demand Response Potentials with High Penetration of Behind-the-Meter Solar-plus-Storage

The goal of this project is to develop advanced methods for day-ahead net-load forecasting, by leveraging the state-of-the-art machine learning techniques. The developed models produce both point and probabilistic forecasts for a variety of use cases, and are versatile to work with different types of data sets. The innovation lies in the novel design of the architectures, leveraging the most recent advances in machine learning that have not been explored in power systems, accompanied by techniques in the broader artificial intelligence fields such as fuzzy systems. This project has achieved the following accomplishments: (1) preprocessing of over 10 data sets covering varying geographical regions, time horizons, and system levels, which form a robust foundation for training and evaluating forecasting models across a wide range of realistic grid scenarios; (2) development of an interactive web app that enables exploratory analysis of load and generation data, and supports better understanding of data trends, anomalies, and correlations, facilitating model development and stakeholder engagement; (3) implementation of over 10 benchmark models for point and probabilistic forecasting, which include a mix of conventional machine learning methods and state-of-the-art deep learning approaches, providing a comprehensive baseline for performance comparison and validation of the proposed models; (4) development of a fuzzy system based gradient boosting model, tailored for small (less than 3 years) data sets, which achieves a mean absolute percentage error (MAPE) of 4% for point forecasting and a 20% improvement in average pinball loss for probabilistic forecasting; (5) development of a Transformer (a state-of-the-art deep learning architecture) based neural network model, tailored for large (3 years or more) data sets, which achieves a MAPE of 2% for point forecasting and a 20% improvement in average pinball loss for probabilistic forecasting; (6) development of a methodology for quantifying DR potential, and extensions of the previous models for multi-target forecasting of net load and DR potential, which achieve a MAPE of 10% for DR potential.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2025

DOE Data Days 2025 Report

The DOE Data Days (D3) workshop brings together data managers, developers, researchers, and program managers across the Department of Energy (DOE) and its national laboratories to highlight data management successes, identify potential synergies and common problems, and establish channels for collaboration across the DOE data management community.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2026

Ground Effects of the 2024 Mother’s Day Superstorm: A Multi-source Observational Analysis

This report presents a brief review of the 2024 Mother’s Day superstorm and its impacts on the near-Earth space environment and the ground-level effects, with emphasis on the latter. Drawing upon observations from multiple sources. we qualitatively illustrate how intense space weather disturbances can generate strong geoelectric fields and drive pronounced geomagnetically induced currents, as reported at numerous locations, particularly within the New Zealand power grids.

58 GEOSCIENCES↗
DOE OSTI2025

Raw ERCOT 60-Day SCED Disclosure Reports

This dataset contains ERCOT plant-level wind power production data at a 15-minute time resolution. Data at ERCOT are called 60-Day SCED Disclosure Report; data product number NP3-965-ER. Raw data are in local time. DST is handled as "skip hour" (12a, 1a, 3a,...) in spring, "extra hour" (12a, 1a, 2a, 2a, 3a,...) in fall.

17 WIND ENERGY↗
DOE OSTI2023

Comparative Study of TESS Photometry and Radial Velocities on Six Early K-type Contact Binaries with Similar Periods around 0.268 Day

High-precision light curves were extracted from TESScut images. Together with APOGEE and LAMOST medium-resolution spectra, a joint study was made for six early K-type contact binary candidates selected unbiasedly with orbital periods around 0.268 day. It is found that all of them (RV CVn, EK Com, V384 Ser, V1038 Her, EH CVn, and CSS_J125403.7+503945) are W-subtype shallow contact systems, though with different mass ratios (1/q = 0.27–0.62). The effective temperature differences between the binary components are around a few hundred kelvins. The original definitions of the A and W subtypes were compared with the customarily used methods, which rely on the shape or photometric solutions of the light curves. The latter two methods are not always reliable; therefore, the radial velocity analysis is strongly recommended. Through a collection of all available K-type contact binaries with both photometric and spectroscopic measurements, it is found that almost all of them are W-subtype systems, except for a few objects that have nearly identical temperatures for binary components. This W-subtype phenomenon for K-type contact binaries should be further checked with more samples in the future. Finally, the physical parameters of the targets were determined with joint data analysis, and the multiplicity is discussed for these targets. Objects V384 Ser and RV CVn are confirmed to very likely be triple systems from comprehensive analysis, while V1038 Her is a candidate of a triple system based on photometric and spectroscopic solutions.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2023

The Atacama Cosmology Telescope: Systematic Transient Search of 3 Day Maps

We conduct a systematic search for transients in 3 yr of data (2017–2019) from the Atacama Cosmology Telescope (ACT). ACT covers 40% of the sky at three bands spanning from 77–277 GHz. Analysis of 3 day mean-subtracted sky maps, which were match filtered for point sources, yielded 29 transient detections. Eight of these transients are due to known asteroids, and three others were previously published. Four of these events occur in areas with poor noise models and thus we cannot be confident they are real transients. We are left with 14 new transient events occurring at 11 unique locations. All of these events are associated with either rotationally variable stars or cool stars. Ten events have flat or falling spectra indicating radiation from synchrotron emission. One event has a rising spectrum indicating a different engine for the flare.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2024

Performance of a Prototype Heliostat Having a Twisting Mechanism to Maintain Focus Throughout the Day

A prototype heliostat has been designed and built with a rectangular reflector whose shape is altered automatically through the day, to maximize concentration at the receiver. The shape changes needed to form solar disc images, which give the highest possible concentration, can be realized by twisting the reflector from its corners, provided that a target-oriented, dual-axis mount is used. Then a cam mechanism connected to the second (cross) axis drive, turning with the angle of incident sunlight, may be used to twist the reflector as needed. Our prototype reflector comprises a single glass mirror, 2.4 m x 3.3 m, attached to a steel frame. Four diagonal back struts extend from the central mechanism out to the rectangular frame corners. The glass mirror of the prototype is attached to the steel frame by 58 screw actuators. Before twisting the frame, the glass shape is adjusted to the biconic shape needed to form a 1 m diameter disc image on a 113 m distant target when sunlight is incident at 60°. To form disc images over the full range of angles of incidence from 0° (normal incidence) to 70°, the struts push the corners up and down by up to 17 mm. A reflectometry metrology system has been used to set the 58 adjustment screws for the initial shape to an accuracy of ≤ 0.6 mrad, and to measure the accuracy of the different twisted shapes. The prototype will be tested at NSTTF early next year.

14 SOLAR ENERGY↗
NASA NTRS1963

THIRTY DAY ENDURANCE TEST OF A 30KW ARC JET ENGINE

Details are presented on a 30-day run of a radiation cooled thermal arc jet engine. The engine performed satisfactorily throughout the test period, maintaining a thrust of 250 grams and a propellant specific impulse greater than 1000 seconds a t an input power level of 30 kilowatts. The resulting propulsive efficiency was greater than 40 percent. Visual examination of the arc discharge through a quartz constrictor indicates that there is a smooth, constant diameter, bright core extending from the cathode completely through the constrictor to the cathode. Photographic observations on the arc discharge, using a red filter, indicate that the center of the column is darker than the outside: and this, in turn, suggests that the maximum core temperature is greater than 20,000°K. Calculations on the energy flow rate through a fully developed laminar column, combined with the experimental observation that the longitudinal energy flux gradient along the column is small, suggest that there may be a region of high volumetric energy release in the vicinity of the cathode tip.

Arc jet↗