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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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At least 73 records · Page 4
All sourcesNASA NTRSDOE OSTI
NASA NTRSDate not supplied

Small Satellite Reliability Initiative (SSRI) Knowledge Base Tool: Use Case Review and Future Functionality and Content Direction

NASA’s Small Satellite Reliability Initiative (SSRI), in conjunction with NASA’s Small Spacecraft Systems Virtual Institute (S3VI), has developed the SSRI Knowledge Base to improve mission confidence for small spacecraft. The SSRI is a collaborative activity with broad participation from civil, Department of Defense, and both national and international commercial space systems providers and stakeholders. The S3VI is jointly sponsored by NASA’s Space Technology Mission Directorate and Science Mission Directorate. The SSRI Knowledge Base is a comprehensive and searchable online tool that consolidates and organizes resources, best practices, and lessons learned from previous small satellite missions sponsored by NASA, other government agencies, and academia. This free, publicly available tool is available to the entire SmallSat community at https://s3vi.ndc.nasa.gov/ssri-kb/. The SSRI Knowledge Base provides vetted, high-quality sources of information on elements that are key to successful small satellite missions. These resources include SSRI working group generated documents and presentations in addition to existing guides, publications, standards, software tools, websites, and books. The Knowledge Base is fully searchable, offers downloadable content when possible, and otherwise links to or references content directly from within the tool. All 58 of the planned topic pages that comprise the SSRI Knowledge Base have been recently completed and include over 450 unique resources that are now available for review. Over the past several months, significant enhancements to the tool’s capabilities have been developed and implemented. These enhancements consist of the completed baseline content, an Application Programming Interface (API), improved user interfaces, new interfaces for crowdsourcing of content and user ratings, and custom website analytics to inform future development. This presentation and paper will discuss the motivation for the SSRI Knowledge Base, review educational use case(s), and outline plans for further development. The 2022 session topic that best fits the abstract (select only one): Coordinating Successful Educational Programs

Small Spacecraft↗
NASA NTRSDate not supplied

Small Satellite Reliability Initiative (SSRI) Knowledge Base Tool: Update and Future Direction

The Small Satellite Reliability Initiative (SSRI)Knowledge Base is a comprehensive and searchable online tool that consolidates and organizes resources, best practices, and lessons learned from previous small satellite missions sponsored by NASA, other government agencies, and academia. This free, publicly available tool is available to the entire SmallSat community. The SSRI Knowledge Base provides vetted, high-quality sources of information on elements that are key to successful small satellite missions. These resources include SSRI working group generated documents and presentations in addition to existing guides, publications, standards, software tools, websites, and books. The Knowledge Base is fully searchable, offers downloadable content when possible, and otherwise links to or references content directly from within the tool. This presentation and paper will discuss the motivation for and development of the SSRI Knowledge Base, demonstrate the existing tool, and outline plans for further development. The SSRI is a collaborative activity with broad participation from civil, Department of Defense, and both national and international commercial space systems providers and stakeholders. NASA’s Small Spacecraft Systems Virtual Institute (S3VI) funds the SSRI Knowledge Base. The S3VIis jointly sponsored by NASA’s Space Technology Mission Directorate and Science Mission Directorate.

Small Spacecraft↗
NASA NTRSDate not supplied

The SSRI Knowledge Base Tool: Current Tool Functionality Review and Planned Future Enhancements

NASA’s Small Satellite Reliability Initiative (SSRI), in conjunction with NASA’s Small Spacecraft Systems Virtual Institute (S3VI), has developed the SSRI Knowledge Base to improve mission confidence for small spacecraft. The SSRI Knowledge Base provides vetted, high-quality sources of information on elements that are key to successful small spacecraft missions. These resources include SSRI working group generated documents and presentations in addition to existing guides, publications, standards, software tools, websites, and books. The Knowledge Base is fully searchable, offers downloadable content when possible, and otherwise links to or references content directly from within the tool. All 58 of the planned topic pages that comprise the SSRI Knowledge Base have been recently completed and include over 450 unique resources that are now available for review. Over the past several months significant enhancements to the tool’s capabilities have been developed and implemented. These enhancements consist of the completed baseline content; development of an Application Programming Interface (API); improved user interfaces; scalable and searchable Best Practices and Lessons Learned (BPLL) lists with ratings; and custom website analytics. The SSRI Knowledge Base is a comprehensive and searchable online tool that consolidates and organizes resources, best practices, and lessons learned from previous small spacecraft missions sponsored by NASA, other government agencies, and academia. This free, publicly available tool is available to the entire SmallSat community at: NASA SSRI Knowledge Base | Explore. This presentation will discuss the motivation for and development of the SSRI Knowledge Base, demonstrate the existing tool, share how the smallsat community can get involved and outline plans for further enhancement development. The SSRI is a collaborative activity with broad participation from civil, Department of Defense, and both national and international commercial space systems providers and stakeholders. The S3VI is jointly sponsored by NASA’s Space Technology Mission Directorate and Science Mission Directorate.

Small Spacecraft↗
NASA NTRSDate not supplied

Small Satellite Reliability Initiative (SSRI) Knowledge Base Tool: Update and Future Direction

NASA’s Small Satellite Reliability Initiative (SSRI), in conjunction with NASA’s Small Spacecraft Systems Virtual Institute (S3VI), has developed the SSRI Knowledge Base to improve mission confidence for small spacecraft. The SSRI Knowledge Base is a comprehensive and searchable online tool that consolidates and organizes resources, best practices, and lessons learned from previous small satellite missions sponsored by NASA, other government agencies, and academia. This free, publicly available tool is available to the entire SmallSat community at: NASA SSRI Knowledge Base | Explore. The SSRI Knowledge Base provides vetted, high-quality sources of information on elements that are key to successful small satellite missions. These resources include SSRI working group generated documents and presentations in addition to existing guides, publications, standards, software tools, websites, and books. The Knowledge Base is fully searchable, offers downloadable content when possible, and otherwise links to or references content directly from within the tool. All 58 of the planned topic pages that comprise the SSRI Knowledge Base have been recently completed and include over 450 unique resources that are now available for review. Over the past several months significant enhancements to the tool’s capabilities have been developed and implemented. These enhancements consist of the completed baseline content; development of an Application Programming Interface (API); improved user interfaces; scalable and searchable Best Practices and Lessons Learned (BPLL) lists with ratings; and custom website analytics. This presentation and paper will discuss the motivation for and development of the SSRI Knowledge Base, demonstrate the existing tool, and outline plans for further development. The SSRI is a collaborative activity with broad participation from civil, Department of Defense, and both national and international commercial space systems providers and stakeholders. The S3VI is jointly sponsored by NASA’s Space Technology Mission Directorate and Science Mission Directorate.

Small Spacecraft↗
NASA NTRSDate not supplied

Small Satellite Reliability Initiative (SSRI) Knowledge Base Tool: Use Case Review and Future Functionality and Content Direction

NASA’s Small Satellite Reliability Initiative (SSRI), in conjunction with NASA’s Small Spacecraft Systems Virtual Institute (S3VI), has developed the SSRI Knowledge Base to improve mission confidence for small spacecraft. The SSRI Knowledge Base is a comprehensive and searchable online tool that consolidates and organizes resources, best practices, and lessons learned from previous small satellite missions sponsored by NASA, other government agencies, and academia. This free, publicly available tool is available to the entire SmallSat community at: NASA SSRI Knowledge Base | Explore. The SSRI Knowledge Base provides vetted, high-quality sources of information on elements that are key to successful small satellite missions. These resources include SSRI working group generated documents and presentations in addition to existing guides, publications, standards, software tools, websites, and books. The Knowledge Base is fully searchable, offers downloadable content when possible, and otherwise links to or references content directly from within the tool. All 58 of the planned topic pages that comprise the SSRI Knowledge Base have been recently completed and include over 450 unique resources that are now available for review. Over the past several months significant enhancements to the tool’s capabilities have been developed and implemented. These enhancements consist of the completed baseline content; development of an Application Programming Interface (API); improved user interfaces; scalable and searchable Best Practices and Lessons Learned (BPLL) lists with ratings; and custom website analytics. This presentation and paper will discuss the motivation for and development of the SSRI Knowledge Base, review of potential use case(s), and outline plans for further development and content generation. The SSRI is a collaborative activity with broad participation from civil, Department of Defense, and both national and international commercial space systems providers and stakeholders. The S3VI is jointly sponsored by NASA’s Space Technology Mission Directorate and Science Mission Directorate.

Small Spacecraft↗
NASA NTRS1999

Aeronautics and Space Report of the President: Fiscal Year 1998 Activities

The National Aeronautics and Space Act of 1958 directed the annual Aeronautics and Space Report to include a "comprehensive description of the programmed activities and the accomplishments of all agencies of the United States in the field of aeronautics and space activities during the preceding calendar year. In recent years, the reports have been prepared on a fiscal year (FY) basis, consistent with the budgetary period now used in programs of the Federal Government. This year's report covers activities that took place from October 1, 1997, through September 30, 1998. The activities of agencies included are NASA, the Department of Defense, The Federal Aviation Administration, the Department of Commerce, the Department of the Interior, the Federal Communications Commission, the Department of Agriculture, the National Science Foundation, the Department of State, the Department of Energy, the Smithsonian Institution, the Arms Control and Disarmament Agency, the Environmental Protection Agency, and the U.S. Information Agency. Appendices cover the U.S. Government Spacecraft Record, World Record of Space Launches Successful in Attaining Earth Orbit or Beyond , Successful Launches to Orbit on U.S. Launch Vehicles, October 1, 1997-September 30, 1998, U.S. and Russian Human Space Flights, 1961-September 30, 1998, U.S. Space Launch Vehicles, Space Activities of the U.S. Government-Historical Budget Summary, Space Activities of the U.S. Government-Budget Authority in Equivalent FY 1998 Dollars, Federal Space Activities Budget, Federal Aeronautics Budget, and a glossary

Source record↗
DOE OSTI2024

OASIS: Offsetting Active Reconstruction Attacks in Federated Learning

Federated Learning (FL) has garnered significant attention for its potential to protect user privacy while enhancing model training efficiency. For that reason, FL has found its use in various domains, from health care to industrial engineering, especially where data cannot be easily exchanged due to sensitive information or privacy laws. However, recent research has demonstrated that FL protocols can be easily compromised by active reconstruction attacks executed by dishonest servers. These attacks involve the malicious modification of global model parameters, allowing the server to obtain a verbatim copy of users' private data by inverting their gradient updates. Tackling this class of attack remains a crucial challenge due to the strong threat model. In this paper, we propose a defense mechanism, namely OASIS, based on image augmentation that effectively counteracts active reconstruction attacks while preserving model performance. We first uncover the core principle of gradient inversion that enables these attacks and theoretically identify the main conditions by which the defense can be robust regardless of the attack strategies. We then construct our defense with image augmentation showing that it can undermine the attack principle. Comprehensive evaluations demonstrate the efficacy of the defense mechanism highlighting its feasibility as a solution.

deep neural networks↗
NASA NTRS2000

Guns and High Gas Output Devices Panel: Introduction

A new panel known as the Guns and High Gas Output Panel was organized in 1999 under the auspices of the JANNAF Propellant and Characterization SubCommittee (PDCS). This is an introduction to our first meeting, purpose of the panel, and the scope of activities to be covered. The primary purpose of the panel is very simple: to provide a single focal point for interfacing Government Laboratories (Department of Defense and Department of Energy) and commercial industry researchers to share R&D activities and findings (i.e. facilitate the exchange of information) specifically aimed at gun-launched propulsion and high-gas output devices (gas generators and air bag inflators). Specific areas of interest included in the Panel's scope (and the Technical Data Base) are the following: (1) new propellant formulations and chemistry, (2) new ingredients, (3) ballistic effects of the new formulations and ingredients, (4) new processing methods unique to gun propellants, (5) thermochemistry of new ingredients, (6) unique physical and mechanical properties, (7) burning rates of new propellants and small scale closed bomb testing, (8) plasma effects on the propellant, and (9) unique safety and insensitive munitions properties.

Simmons, Ronald L.↗
NASA NTRS1993

STS-53 Space Shuttle mission report

The STS-53 Space Shuttle Program Mission Report provides a summary of the Orbiter, External Tank (ET), Solid Rocket Booster/Redesigned Solid Rocket Motor (SRB/RSRM), and the Space Shuttle Main Engine (SSME) subsystems performance during the fifty-second flight of the Space Shuttle Program, and the fifteenth flight of the Orbiter vehicle Discovery (OV-103). In addition to the Orbiter, the flight vehicle consisted of an ET, which was designated as ET-49/LWT-42; three SSME's, which were serial numbers 2024, 2012, and 2017 in positions 1, 2, and 3, respectively; and two SRB's, which were designated BI-055. The lightweight RSRM's that were installed in each SRB were designated 360L028A for the left SRB, and 360L028B for the right SRB. The primary objective of this flight was to successfully deploy the Department of Defense 1 (DOD-1) payload. The secondary objectives of this flight were to perform the operations required by the Glow Experiment/Cryogenic Heat Pipe Experiment Payload (GCP); the Hand-Held, Earth-Oriented, Real-Time, Cooperative, User-Friendly, Location-Targeting and Environmental System (HERCULES); the Space Tissue Loss (STL); the Battlefield Laser Acquisition Sensor Test (BLAST); the Radiation Monitoring Equipment-III (RME-III); the Microcapsules in Space-1 (MIS-1); the Visual Function Tester-2 (VFT-2); the Cosmic Radiation Effects and Activation Monitor (CREAM); the Clouds Logic to Optimize Use of Defense Systems-1A (CLOUDS-1A); the Fluids Acquisition and Resupply Experiment (FARE); and the Orbital Debris Radar Calibration Spheres (ODERACS). In addition to presenting a summary of subsystem performance, this report also discusses each Orbiter, ET, SSME, SRB, and RSRM in-flight anomaly in the applicable section of the report. Listed in the discussion of each anomaly is the officially assigned tracking number as published by each Project Office in their respective Problem Tracking List. All times given in this report are in Greenwich mean time (G.m.t.) as well as mission elapsed time (MET).

Fricke, Robert W., Jr.↗
NASA NTRS1974

Adaptations of advanced safety and reliability techniques to petroleum and other industries

The underlying philosophy of the general approach to failure reduction and control is presented. Safety and reliability management techniques developed in the industries which have participated in the U.S. space and defense programs are described along with adaptations to nonaerospace activities. The examples given illustrate the scope of applicability of these techniques. It is indicated that any activity treated as a 'system' is a potential user of aerospace safety and reliability management techniques.

Purser, P. E.↗
NASA NTRS2018

Key Challenges in Capturing a Boulder for the Asteroid Redirect Robotic Mission

NASA's proposed Asteroid Redirect Mission planned to demonstrate the capability to collect a large boulder from the surface of a Near Earth Asteroid, use that mass of the boulder to demonstrated enhanced asteroid deflection, and return the boulder for future exploration as part of the Asteroid Redirect Crewed Mission. In June of 2017 NASA decided not to continue the Asteroid Redirect Mission. Prior to this decision, the team had made tremendous progress on detailed designs for precision landing, active touchdown, boulder collection, and formation-flying planetary defense

Redirect↗
NASA NTRSDate not supplied

Small Satellite Reliability Initiative (SSRI) Knowledge Base Tool: Use Case Review and Future Functionality and Content Direction

The Small Satellite Reliability Initiative (SSRI) Knowledge Base is a comprehensive and searchable online tool that consolidates and organizes resources, best practices, and lessons learned from previous small satellite missions sponsored by NASA, other government agencies, and academia. This free, publicly available tool is available to the entire SmallSat Community. The SSRI Knowledge Base provides vetted, high-quality sources of information on elements that are key to successful small satellite missions. These resources include SSRI working group generated documents and presentations in addition to existing guides, publications, standards, software tools, websites, and books. The Knowledge Base is fully searchable, offers downloadable content when possible, and otherwise links to or references content directly from within the tool. This presentation and paper will discuss the motivation for the SSRI Knowledge Base, review educational use cases, and outline plans for further development. The SSRI is a collaborative activity with broad participation from civil, U.S. Department of Defense, and both national and international commercial space systems providers and stakeholders. NASA’s Small Spacecraft Systems Virtual Institute (S3VI) funds the SSRI Knowledge Base. The S3VI is jointly sponsored by NASA’s Space Technology Mission Directorate and Science Mission Directorate. This presentation and paper will discuss the motivation for the SSRI Knowledge Base, review educational use case(s), and outline plans for further development.

Small Spacecraft↗
NASA NTRS2006

Novel Concept for LSS Based on Advanced Microalgal Biotechnologies

One of the key issues for successful human space exploration is biomedical life support in hostile space and planetary environments that otherwise cannot sustain life. Bioregenerative life support systems (LSS) are one of the options for atmospheric regeneration. To date, no bioregenerative LSS has shown capability for 100% air regeneration. Nor have these LSS been robust enough to simultaneously provide a regenerable complete food source. In contrast to microalgae, traditional plant approaches, e.g. wheat and lettuce, are lacking essential amino acids, vitamins, and micronutrients. Moreover, the rate of photosynthesis by microalgae significantly exceeds that of high plants. Nevertheless, the employment of microalgae in LSS technology was restricted, until recently, due to high water demands. Also the per person requirement of a 40L volume of microalgae in a photobioreactor, to provide daily O2 production, made an algae-based approach less attractive. By employing a vertically stacked membrane bioreactor, coupled with a solar tracker and photon-delivery system, a lightweight air revitalization system for space based applications, with minimal water requirements, can be developed. Our preliminary estimations suggest that a membrane bioreactor, 8m3 in volume, comprised of 80m2 (twenty 2m x 2m membranes, each spaced 10 cm apart), and a total of 70L of water could produce 2.7 kg of dried microalgal biomass that would supply the energy and essential amino acid requirements, as well as producing sufficient O2 for the daily needs of a 15 member crew. Research on the biochemical content of edible blue-green alga Spirulina (Arthrospira) platensis shows a wide spectrum of stable Spirulina mutants with an enhanced content of amino acids, -carotene, and phycobilliprotein c-phycocyanin. Feeding animals suffering from radiation-induced lesions, c-phycocyanin, extracted from strain 27G, led to a correction in the decrement of dehydrogenase activity and energy-rich phosphate levels, as well as improved antioxidant defense and pyruvate levels, compared to untreated animals. Experimental anemia in rats was corrected by feeding Spirulina platensis strains 198B and 27G, (with an enhanced content of methionine, phycobiliproteins and carotenoids). Spirulina was recently shown by Ananyev et al, 2005, to be an oxygenic organism with the highest level of photosystem II activity (O2 production). We propose therefore to develop a design for membrane-based photoreactors for Lunar and Mars exploration habitat LSS, for the cultivation of genetically modified strains of Spirulina to scrub CO2 and supply astronauts with O2, protein, vitamins, and immunostimulators.

Brown, I.↗
DOE OSTI2025

A bipartite bacterial virulence factor targets the complement system and neutrophil activation

Abstract The complement system and neutrophils constitute the two main pillars of the host innate immune defense against infection by bacterial pathogens. Here, we identify T-Mac, a novel virulence factor of the periodontal pathogen Treponema denticola that allows bacteria to evade both defense systems. We show that T-Mac is expressed as a pre-protein that is cleaved into two functional units. The N-terminal fragment has two immunoglobulin-like domains and binds with high affinity to the major neutrophil chemokine receptors FPR1 and CXCR1, blocking N -formyl-Met-Leu-Phe- and IL-8-induced neutrophil chemotaxis and activation. The C-terminal fragment functions as a cysteine protease with a unique proteolytic activity and structure, which degrades several components of the complement system, such as C3 and C3b. Murine infection studies further reveal a critical T-Mac role in tissue damage and inflammation caused by bacterial infection. Collectively, these results disclose a novel innate immunity-evasion strategy, and open avenues for investigating the role of cysteine proteases and immunoglobulin-like domains of gram-positive and -negative bacterial pathogens.

Kurniyati, Kurni↗
NASA NTRS1986

Overview of free-piston Stirling SP-100 activities at the NASA Lewis Research Center

An overview of the National Aeronautics and Space Administration (NASA) Lewis Research Center (LeRC) SP-100 free-piston Stirling engine activities is presented. These activities are being conducted in support of the Department of Defense (DOD), Department of Energy (DOE), and NASA. The space-power technology effort, under SP-100, addresses the status of the 25 kWe Space Power Demonstrator Engine (SPDE). Another facet of the SP-100 project covers the status of an endurance test. Dynamic balancing of the SPDE engine is discussed along with a summary covering the parametric results of a study showing the relationship between power-converter specific weight and efficiency both as a function of Stirling engine heater to cooler temperature ratio. Design parameters and conceptual design features are presented for a 25 kWe, single-cylinder free-piston Stirling space-power converter. And finally, a description of a hydrodynamic gas bearing concept is presented.

Slaby, J. G.↗
NASA NTRS1992

Shared visions: Partnership of Rockwell International and NASA Cost Effectiveness Enhancements (CEE) for the space shuttle system integration program

As a result of limited resources and tight fiscal constraints over the past several years, the defense and aerospace industries have experienced a downturn in business activity. The impact of fewer contracts being awarded has placed a greater emphasis for effectiveness and efficiency on industry contractors. It is clear that a reallocation of resources is required for America to continue to lead the world in space and technology. The key to technological and economic survival is the transforming of existing programs, such as the Space Shuttle Program, into more cost efficient programs so as to divert the savings to other NASA programs. The partnership between Rockwell International and NASA and their joint improvement efforts that resulted in significant streamlining and cost reduction measures to Rockwell International Space System Division's work on the Space Shuttle System Integration Contract is described. This work was a result of an established Cost Effectiveness Enhancement (CEE) Team formed initially in Fiscal Year 1991, and more recently expanded to a larger scale CEE Initiative in 1992. By working closely with the customer in agreeing to contract content, obtaining management endorsement and commitment, and involving the employees in total quality management (TQM) and continuous improvement 'teams,' the initial annual cost reduction target was exceeded significantly. The CEE Initiative helped reduce the cost of the Shuttle Systems Integration contract while establishing a stronger program based upon customer needs, teamwork, quality enhancements, and cost effectiveness. This was accomplished by systematically analyzing, challenging, and changing the established processes, practices, and systems. This examination, in nature, was work intensive due to the depth and breadth of the activity. The CEE Initiative has provided opportunities to make a difference in the way Rockwell and NASA work together - to update the methods and processes of the organizations. The future success of NASA space programs and Rockwell hinges upon the ability to adopt new, more efficient and effective work processes. Efficiency, proficiency, cost effectiveness, and teamwork are a necessity for economic survival. Continuous improvement initiatives like the CEE are, and will continue to be, vehicles by which the road can be traveled with a vision to the future.

Bejmuk, Bohdan I.↗
NASA NTRS2013

DMSP Auroral Charging at Solar Cycle 24 Maximum

It has been well established that polar orbiting satellites can experience mild to severe auroral charging levels (on the order of a few hundred volts to few kilovolts negative frame potentials) during solar minimum conditions (Frooninckx and Sojka, 1992; Anderson and Koons, 1996; Anderson, 2012). These same studies have shown a strong reduction in charging during the rising and declining phases of the past few solar cycles with a nearly complete suppression of auroral charging at solar maximum. Recently, we have observed examples of high level charging during the recent approach to Solar Cycle 24 solar maximum conditions not unlike those reported by Frooninckx and Sojka (1992). These observations demonstrate that spacecraft operations during solar maximum cannot be considered safe from auroral charging when solar activity is low. We present a survey of auroral charging events experienced by the Defense Meteorological Satellite Program (DMSP) F16 satellite during Solar Cycle 24 maximum conditions. We summarize the auroral energetic particle environment and the conditions necessary for charging to occur in this environment, we describe how the lower than normal solar activity levels for Solar Cycle 24 maximum conditions are conducive to charging in polar orbits, and we show examples of the more extreme charging events, sometimes exceeding 1 kV, during this time period.

Chandler, Michael↗