SEARCH · Search NASA
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.
The design of the Alert Production DataBase (APDB) and Prompt Products DataBase (PPDB) has been evolving for the past few years as a result of various tests and updated requirements. This technical note describes the current state of these systems, as well as issues related to scalability and performance. It also discusses unresolved issues in the system's architecture and possible future directions.
An overview of the 1975 NASA Research and Technology efforts directly focused on general aviation is presented. Current status and accomplishments during the past year are described. An updated bibliography of technical reports generated by the NASA program, including seven recently declassified reports on airplane noise reduction, is included as an Appendix to this report.
The feasibility of designing propellers by an optimization procedure is investigated. A scheme, which solves the full potential flow equation about a propeller by line relaxation, is modified so that the iterative solutions of the flow equation and the design parameters are updated simultaneously. Some technical problems in using optimization for designing propellers with maximum efficiency are identified. Approaches for overcoming these problems are presented.
A far-infrared heterodyne spectrometer was designed and built by our group for observations of atomic and molecular lines from interstellar clouds. Linewidths as narrow as 1 km/s can be expected from such regions, and so the spectrometer is designed with sub-km/s resolution so that observed line profiles will be resolved. Since its debut on the Kuiper Airborne Observatory (KAO) in 1985, the instrument has been used in regular annual flight programs from both Moffett Field, CA and Christchurch, NZ. The basic plan of the spectrometer remains unchanged from the original design presented at the previous airborne science symposium. Numerous improvements and updates to the technical capability have of course been included over the many years of operational service.
This effort is a detailed analysis of existing microelectronics and photonics test bed satellite data from one experiment, the bipolar test board, looking to improve our understanding of the enhanced low dose rate sensitivity (ELDRS) phenomenon. Over the past several years, extensive total dose irradiations of bipolar devices have demonstrated that many of these devices exhibited ELDRS. In sensitive bipolar transistors, ELDRS produced enhanced degradation of base current, resulting in enhanced gain degradation at dose rates <0.1 rd(Si)/s compared to similar transistors irradiated at dose rates >1 rd(Si)/s. This Technical Publication provides updated information about the test devices, the in-flight experiment, and both flight-and ground-based observations. Flight data are presented for the past 5 yr of the mission. These data are compared to ground-based data taken on devices from the same date code lots. Information about temperature fluctuations, power shutdowns, and other variables encountered during the space flight are documented.
Over the last year, the National Aeronautics and Space Administration (NASA) has continued to refine the understanding and prioritization of technology gaps that must be closed in order to achieve Evolvable Mars Campaign objectives and near term objectives in the cislunar proving ground. These efforts are reflected in updates to the technical area roadmaps released by NASA in 2015 and have guided technology development and maturation tasks that have been sponsored by various programs. This paper provides an overview of the refined Environmental Control and Life Support (ECLS) strategic planning, as well as a synopsis of key technology and maturation project tasks that occurred in 2014 and early 2015 to support the strategic needs. Plans for the remainder of 2015 and subsequent years are also described.
Keck Interferometer is a NASA-funded project to combine the two 10 m Keck telescopes for high sensitivity near-infrared fringe visibility measurements, nulling interferometry at 10 µm to measure the quantity of exozodiacal emission around nearby stars, and differential-phase measurements to detect "hot-Jupiters" by their direct emission. Recent activity has included formal visibility mode commissioning, as well as science observations, and we briefly review some of the significant technical aspects and updates to the system. We have also completed laboratory development of the nuller. The nuller uses two modified Mach-Zehnder input nullers, a Michelson cross combiner, and a 10 µm array camera to produce background-limited null measurements. To provide required temporal stability for the nuller, the system incorporates end-to-end laser metrology with phase referencing from two 2.2 µm fringe trackers. The nuller recently completed its pre-ship review and is being installed on the summit. After nuller integration and test, the differential phase mode will be deployed, which uses a 2-5 µm fringe detector in combination with a precision path length modulator and a vacuum delay line for dispersion control.
The third DIP workshop’s topic is DIP for Flight Operators and Consumers. Participants will receive insight the consumer onboarding process and steps to take to consume from the platform. Showcase demos will be provided covering data integration services, data analytics using ML/AI technologies, and Collaborative Digital Decision Reroute (CDDR) capabilities. More details on service performance metrics will be discussed as well as updates on the technical development plan and schedule. Participants interested in consuming DIP services are highly encouraged to attend this workshop and provide feedback.
The International Criticality Safety Benchmark Evaluation Project (ICSBEP) has continued its work generating evaluations of new and historical criticality benchmark experiments since the last update to the nuclear criticality safety community at the 11th International Conference on Nuclear Criticality Safety (ICNC 2019) in Paris, France. Three additional versions of the ICSBEP Handbook have been published since that update, and the Technical Review Group (TRG) held two in-person (in 2019 and 2023) and three virtual (2020 and 2021) meetings to review and approve additional benchmarks. The 2019 edition of the ICSBEP Handbook included five new evaluations with 79 new configurations, the 2020 version of the ICSBEP Handbook contained five new evaluations totaling 76 new configurations, and the 2021 version of the ICSBEP handbook contained five new evaluations with a total of 57 different configurations. The ICSBEP TRG met in October and December 2021, to review benchmarks for potential inclusion in the 2022 ICSBEP Handbook, with seven evaluations receiving provisional approval pending resolution of review group comments. Final comment resolution for some of these evaluations is currently underway and handbook publication should be completed soon. The ICSBEP TRG met again in person in April 2023 to review benchmarks for the 2023 ICSBEP Handbook, provisionally approving 7 new evaluations. The ICSBEP continues to deliver high-quality, peer reviewed evaluations of experiments relevant to the nuclear criticality safety community.
The International Criticality Safety Benchmark Evaluation Project (ICSBEP) has continued its work generating evaluations of new and historical benchmark experiments since the last update to the nuclear criticality safety (NCS) community at the 12th International Conference on Nuclear Criticality Conference held in 2023. One additional version of the ICSBEP Handbook has been published since that update, and the Technical Review Group (TRG) held two in-person meetings to review and approve additional benchmarks. The 2022 and 2023 editions of the handbook were combined into one release (published in November 2024) and contained 13 new evaluations with 46 different configurations and two major revisions to existing evaluations. The 2024 version of the handbook, currently under publication review, will contain two new evaluations with 15 new configurations and one major revision to HEU-MET-FAST-028, the evaluation of Flattop with a uranium core. The ICSBEP TRG met again in person in April 2025 to review benchmarks for the 2025 ICSBEP Handbook and final comment resolution is currently ongoing. Many of the new benchmarks represent contemporaneous experiments that have been specifically optimized to provide validation cases relevant to the NCS community. One major area of focus for new critical experiments is to target the sparsely populated intermediate energy (or resonance) region. Another focus of many of the new benchmarks is to provide experiments sensitive to different materials, such as chlorine, hafnium, tantalum, titanium, molybdenum, chromium, and polymethyl methacrylate (PMMA, or Lucite). The ICSBEP continues to deliver high-quality, peer reviewed evaluations of integral experiments relevant to the nuclear data community.
The USA Structures (USS) foundational data layer remains a critical national dataset for supporting damage assessment and disaster response across the United States. Maintaining its relevance requires regular updates to reflect changes in the built environment and to ensure the accuracy of key structural attributes.
This report describes the assessment of the recently published ANSI/AISC N690-18, Specification for Safety-Related Steel Structures for Nuclear Facilities. This work was performed for the U.S. Nuclear Regulatory Commission for potential endorsement of N690-18 for use in the design of nuclear power plants. Currently the NRC endorses the use of an earlier version: N690-1994 (R2004), and thus, a technical review of the updated N690 Specification, which contains significant changes, is warranted. The N690-18 Specification reflects advances and improvements in steel design gained from experience, analytical studies, and experimental data over the years. The N690-18 specification also contains a new Appendix N9 that addresses the design of safety-related steel-plate composite (SC) walls which are a relatively new type of structural member for which previously there has not been any U.S. code or standard that governs its design. The technical review of N690-18 was performed in order to assess the adequacy of the provisions for use by the NRC in updating its regulatory guidance for nuclear power plants. The research developed the technical basis for acceptance of the new specification and also identified areas where additional staff guidance is needed for the design of safety-related steel structures at nuclear power plants. The results of the research have determined that the N690-18 specification is a significant enhancement from the N690-1994 (R2004) edition. The new specification contains substantial upgrades in the design of structural steel and includes new provisions for design of SC wall sections, which can benefit the nuclear power industry as well as the NRC review process. All of the improvements, if endorsed by the NRC with certain regulatory positions, will allow clearer and more consistent regulatory guidance, and will avoid the need for justification by licensees and related reviews each time certain methods or approaches are used.
Each quarter, the National Renewable Energy Laboratory (NREL) conducts the Quarterly Solar Industry Update, a presentation of technical trends within the solar industry. Each presentation focuses on global and U.S. supply and demand, module and system price, investment trends and business models, and updates on U.S. government programs supporting the solar industry. This quarter we also provide additional analysis on the domestic content of U.S. PV installations.
Each quarter, the National Renewable Energy Laboratory (NREL) conducts the Quarterly Solar Industry Update, a presentation of technical trends within the solar industry. Each presentation focuses on global and U.S. supply and demand, module and system price, investment trends and business models, and updates on U.S. government programs supporting the solar industry.
Each quarter, the National Renewable Energy Laboratory (NREL) conducts the Quarterly Solar Industry Update, a presentation of technical trends within the solar industry Each presentation focuses on global and U.S. supply and demand, module and system price, investment trends and business models, and updates on U.S. government programs supporting the solar industry.
Each quarter, the National Renewable Energy Laboratory (NREL) conducts the Quarterly Solar Industry Update, a presentation of technical trends within the solar industry Each presentation focuses on global and U.S. supply and demand, module and system price, investment trends and business models, and updates on U.S. government programs supporting the solar industry.
Each quarter, the National Renewable Energy Laboratory (NREL) conducts the Quarterly Solar Industry Update, a presentation of technical trends within the solar industry. Each presentation focuses on global and U.S. supply and demand, module and system price, investment trends and business models, and updates on U.S. government programs supporting the solar industry.
Each quarter, the National Renewable Energy Laboratory conducts the Quarterly Solar Industry Update, a presentation of technical trends within the solar industry. Each presentation focuses on global and U.S. supply and demand, module and system price, investment trends and business models, and updates on U.S. government programs supporting the solar industry.