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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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The effect of power/temperature step stress when applied to a variety the zener diode JANTX2N3016B manufactured by Siemens and Motorola is reported. A total of 48 samples from each manufacturer was submitted to the process. In addition, two control sample units were maintained for verification of the electrical parametric testing.
NPAC R&D focus areas include: Advancing U.S. capabilities to detect and characterize nuclear weapon development activities globally, including material production, the movement of special nuclear materials and nuclear weapons, and the testing or use of nuclear weapons, Supporting the development and testing of policy options and technical capabilities for international nuclear safeguards, arms control / treaty verification, nuclear export controls, and nonproliferation initiatives consistent with U.S. Government goals and objectives to enable monitoring and verification, Utilizing uranium, lithium, and high explosives (HE) materials expertise to support national-level activities in nuclear forensics and nuclear detection technology testing and evaluation, Providing unique training and capacity-building programs, particularly with the Nuclear Detection and Sensor Testing Center (NDSTC), and Engaging internationally to promote nonproliferation and arms control norms and best practices through bilateral and multilateral work.
Measurement, Reporting, and Verification (MRV) is a systematic approach to tracking and documenting greenhouse gas (GHG) emissions and emission reductions. MRV can be used across all sectors and for all GHGs to track emissions patterns, evaluate programs, and promote transparency. As methane and other short-lived climate pollutants become critical to mitigating near-term climate change impacts, MRV systems become critical in improving emission inventories; facilitating the development of climate change policies and targets, and tracking and demonstrating progress towards sustainable development. This report focuses on current sectoral issues – including the emerging roles for satellites and remote sensing technologies - and international best practices in MRV policies and programs for non-carbon dioxide (CO 2 ) GHGs including methane, nitrous oxide (N 2 O), and hydrofluorocarbons (HFCs) in specific sectors. Based on international best practices and a review of China’s current MRV system, we offer suggestions for a possible path forward for developing and implementing a stronger non-CO 2 MRV system.
The extent of the influence of the propulsion system exhaust plumes on the vehicle performance and control characteristics is a complex function of vehicle geometry, propulsion system geometry, engine operating conditions and vehicle flight trajectory were investigated. Analytical support of the plume technology test program was directed at the two latter problem areas: (1) definition of the full-scale exhaust plume characteristics, (2) application of appropriate similarity parameters; and (3) analysis of wind tunnel test data. Verification of the two-phase plume and plume impingement models was directed toward the definition of the full-scale exhaust plume characteristics and the separation motor impingement problem.
The analytical effort was aimed at development of numerical model of thermal and mechanical phenomena which occur during seal rub. Finite element programs were develped for studying the temperatures that result from frictional heating during rubs, and the plastic deformation which is caused by rub forces. The experiment phase was originally intended to aid in verification of the results of the analytical model. Experimental techniques were developed for measuring surface temperatures and deformations during single pass rubs. Modifications were made to the device to permit testing at both high and cryogenic temperatures. The results from the experiments are discussed.
In Dec. 1991 TITAN SPECTRON successfully completed its six year effort to design, build, space qualify, test, and deliver the Laser Transmitter Module (LTM) for NASA LaRC's LITE program. The delivered LTM is a three color Q-switched flashlamp pumped Nd:YAG laser that is described as the first true world-class lidar in space. The preliminary design and verification tests results were first presented at the 14th International Laser Radar Conference (ILRC) in 1988. This paper describes not only the delivered product but also the verification and space qualification processes that resulted in the world's first space qualified high powered laser system for environmental exploration from space. Video of the laser operating in a Class 100 clean room and subsystems undergoing 10 G vibration tests will provide a vivid illustration of the key elements that separate a space qualified system from its laboratory counterpart. Flight laser performance measurements form the baseline in post-delivery test results to be presented at this conference.
Earth-to-Orbit Propulsion Technology program is considered. The program's three major technical areas include combustion devices, turbomachinery, and controls and monitoring. Directed toward reducing acquisition and operations risk and cost the ETO program is conducted in two serially-performed categories: technology acquisition and technology validation. The former is constituted of studies, tool building, and bench-scale experimentation. The latter involves next-step verification of the acquisition results and findings, usually leading to a test-bed validated technology 'product'.
abmREPORT Version 3.1 is a Perl script that extracts vital summarization information from the Mars Reconnaissance Orbiter (MRO) aerobraking ABM build process. This information facilitates sequence reviews, and provides a high-level summarization of the sequence for mission management. The script extracts information from the ENV, SSF, FRF, SCMFmax, and OPTG files and burn magnitude configuration files and presents them in a single, easy-to-check report that provides the majority of the parameters necessary for cross check and verification during the sequence review process. This means that needed information, formerly spread across a number of different files and each in a different format, is all available in this one application. This program is built on the capabilities developed in dragReport and then the scripts evolved as the two tools continued to be developed in parallel.
Based on the previous success' of Multi-Element Integration Testing (MEITs) for the International Space Station Program, these type of integrated tests have also been planned for the Constellation Program: MEIT (1) CEV to ISS (emulated) (2) CEV to Lunar Lander/EDS (emulated) (3) Future: Lunar Surface Systems and Mars Missions Finite Element Integration Test (FEIT) (1) CEV/CLV (2) Lunar Lander/EDS/CaL V Integrated Verification Tests (IVT) (1) Performed as a subset of the FEITs during the flight tests and then performed for every flight after Full Operational Capability (FOC) has been obtained with the flight and ground Systems.
The steep learning curve of formal technologies is a well-known barrier to the adoption of formal verification tools in industry. This paper presents VSCode-PVS, a modern integrated development environment for the Prototype Verification System (PVS). This new environment integrates the editing and proof management functionalities of PVS in Visual Studio Code, a popular code editor widely used by software developers. VSCode-PVS provides functionalities that developers expect to find in modern verification tools but are not available in the standard Emacs front-end of PVS, such as auto-completion, point-and-click navigation of definitions, live diagnostics for errors, and literate programming. The main features and architecture of the environment are presented, along with a comparison with other similar tools.
Node 1 (Unity) flew to International Space Station (ISS) on Flight 2A. Node 1 was the first module of the United States On-Orbit Segment (USOS) launched to ISS. The Node 1 ISS Environmental Control and Life Support (ECLS) design featured limited ECLS capability. The main purpose of Node 1 was to provide internal storage by providing four stowage rack locations within the module and to allow docking of multiple modules and a truss segment to it. The ECLS subsystems inside Node 1 were routed through the element prior to launch to allow for easy integration of the attached future elements, particularly the Habitation Module which was planned to be located at the nadir docking port of Node 1. After Node I was on-orbit, the Program decided not to launch the Habitation Module and instead, to replace it with Node 3 (Tranquility). In 2007, the Program became concerned with a potential Russian docking port approach issue for the Russian FGB nadir docking port after Node 3 is attached to Node 1. To solve this concern the Program decided to relocate Node 3 from Node I nadir to Node 1 port. To support the movement of Node 3 the Program decided to build a modification kit for Node 1, an on-orbit feedthrough leak test device, and new vestibule jumpers to support the ECLS part of the relocation. This paper provides a design overview of the modification kit for Node 1, a summary of the Node 1 ECLS re-verification to support the Node 3 relocation from Node 1 nadir to Node 1 port, and a status of the ECLS modification kit installation into Node 1.
An overview of the X-29A functional flight program and concept evaluation program is presented, including some of the unique and different preparations for the first flight. Included are a discussion of the many organizational responsibilities and a description of the program management structure for the test team. Also discussed are preflight ground, flight functional envelope expansion, and flight research test objectives and qualitive results to date for both a limited-envelope flight control system and an expanded-envelope system. The aircraft, including the instrumentation system and measurements, is described. In addition, a discussion is included regarding the use of major support facilities, such as ground and flight simulators, the NASA Western Aeronautical Test Range and mission control center, and the Grumman automated telemetry station. An overview of the associated real-time and postflight batch data processing software approaches is presented. The use of hardware-in-the-loop simulation for independent verification and validation and mission planning and practice is discussed. Also included is a description of the flight-readiness review, the airworthiness and flight safety review, work scheduling, technical briefings, and preflight and postflight crew briefings. The configuration control process used on the X-29A program is described, and its relationship to both simulation and aircraft operations is discussed. An X-29A schedule overview is presented with an outline of a proposed follow-on program.
Data for the purpose of evaluating the effect of power/temperature step stress on the diode JANTX1N3893 manufactured by Siemens and Motorola is presented. A total of 48 samples from each manufacturer were submitted to the process. In addition, two control sample units were maintained for verification of the electrical parametric testing.
The idea is set forth that criteria are developed to assess whether a particular limited-duration signal is evidence of extraterrestrial intelligence (ETI). The nature of short-duration signals is discussed to set the stage for a description of the NASA Microwave Observing Program. Criteria for evaluating the possibility of ETI origin for a signal include length, strength, band width, and accompaniment by a pseudorandom repetition. SETI is described as an educational document that can be employed to illustrate the real difficulties of interstellar communication. It is concluded that to avoid the negative aspects of SETI activities such as the notion of fashioning a return signal the intergenerational nature of interstellar communication be emphasized for the public.
Weather information is an important asset for NASA's Constellation Program in developing the next generation space transportation system to fly to the International Space Station, the Moon and, eventually, to Mars. Weather conditions can affect vehicle safety and performance during multiple mission phases ranging from pre-launch ground processing to landing and recovery operations, including all potential abort scenarios. Meteorological analysis is an important contributor, not only to the development and verification of system design requirements but also to mission planning and active ground operations. Of particular interest are the surface atmospheric conditions at both nominal and abort landing sites for the manned Orion capsule. Weather parameters such as wind, rain, and fog all play critical roles in the safe landing of the vehicle and subsequent crew and vehicle recovery. The Marshall Space Flight Center Natural Environments Branch has been tasked by the Constellation Program with defining the natural environments at potential landing zones. Climatological time series of operational surface weather observations are used to calculate probabilities of occurrence of various sets of hypothetical vehicle constraint thresholds, Data are available for numerous geographical locations such that statistical analysis can be performed for single sites as well as multiple-site network configurations. Results provide statistical descriptions of how often certain weather conditions are observed at the site(s) and the percentage that specified criteria thresholds are matched or exceeded. Outputs are tabulated by month and hour of day to show both seasonal and diurnal variation. This paper will describe the methodology used for data collection and quality control, detail the types of analyses performed, and provide a sample of the results that can be obtained,
This report presents the results of monitoring conducted for water quality, water levels, and institutional controls in FY 2020 by DOE/EM Nevada Program UGTA Activity at CAU 97, Yucca Flat/Climax Mine at the Nevada National Security Site. This report also presents analytical laboratory results (including results of quality assurance/quality control samples, such as field duplicates); and verification of use restrictions, institutional controls, and water use.
The Shuttle flight test plan is detailed, together with the results of tests of the flight control system (FCS). The initial Columbia flights carried 13,000 lb of instrumentation, and will be replaced with a 97 lb package during subsequent flights when further data are desired. The flight test program, besides gathering aerodynamic data, was heavily concerned with the perormance of the SSME (near-nominal), the thermal protection system (the performance and reusability have been demonstrated), and the data processing system (ground verification tests vindicated). Ascent has been nominal, as have orbital maneuvers, and descent roll/yaw has proven smoother than other high performance aircraft. Accelerometers and crewmembers have not been able to sense the smoothness of reentry RCS-controlled maneuvers. The manual controls are noted to serve only in off-nominal situations. The STS is concluded to be a basically sound vehicle, assuring a routine American presence in space.
The results of a four-month, phased effort to develop a Fly-by-Light Technology Development Plan are documented. The technical shortfalls for each phase were identified and a development plan to bridge the technical gap was developed. The production configuration was defined for a 757-type airplane, but it is suggested that the demonstration flight be conducted on the NASA Transport Systems Research Vehicle. The modifications required and verification and validation issues are delineated in this report. A detailed schedule for the phased introduction of fly-by-light system components has been generated. It is concluded that a fiber-optics program would contribute significantly toward developing the required state of readiness that will make a fly-by-light control system not only cost effective but reliable without mitigating the weight and high-energy radio frequency related benefits.