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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 613 records · Page 34
All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

The DSA Toolkit Shines Light Into Dark and Stormy Archives

Web archive collections are created with a particular purpose in mind. A curator selects seeds, or original resources, which are then captured by an archiving system and stored as archived web pages, or mementos. The systems that build web archive collections are often configured to revisit the same original resource multiple times. This is incredibly useful for understanding an unfolding news story or the evolution of an organization. Unfortunately, over time, some of these original resources can go off-topic and no longer suit the purpose for which the collection was originally created. They can go off-topic due to web site redesigns, changes in domain ownership, financial issues, hacking, technical problems, or because their content has moved on from the original topic. Even though they are off-topic, the archiving system will still capture them, thus it becomes imperative to anyone performing research on these collections to identify these off-topic mementos. Hence, we present the Off-Topic Memento Toolkit, which allows users to detect off-topic mementos within web archive collections. The mementos identified by this toolkit can then be separately removed from a collection or merely excluded from downstream analysis. The following similarity measures are available: byte count, word count, cosine similarity, Jaccard distance, Sørensen-Dice distance, Simhash using raw text content, Simhash using term frequency, and Latent Semantic Indexing via the gensim library. We document the implementation of each of these similarity measures. We possess a gold standard dataset generated by manual analysis, which contains both off-topic and on-topic mementos. Using this gold standard dataset, we establish a default threshold corresponding to the best F1 score for each measure. We also provide an overview of potential future directions that the toolkit may take.

96 KNOWLEDGE MANAGEMENT AND PRESERVATION↗
DOE OSTI2020

Fabrication Lessons Learned of Transportation Packaging from the Perspective of a Design Authority - 20322

This paper presents lessons learned regarding fabricating packaging systems from the perspective of a design authority (DA). Capturing and implementing lessons learned is critical for an organization to reduce systematic project risk and thereby promote the likelihood of project success. This paper defines the design authority as the organization responsible for technical design, resolving technical design issues, quality assurance program, and maintenance of the packaging system license. A package system is defined as the packaging, its contents, and auxiliary equipment. Packages are certified by the NRC under 10 CFR 71[1] for transportation by ground. The following lessons learned subjects are presented in the paper: quality assurance, interpretation of drawing dimensional requirements, execution of manufacturing processes, hardware dimensional inspection, and leakage rate testing. All discrepancies presented in this paper have been resolved as described in the appropriate final data package. All described package systems are in compliance with their Safety Analysis Report (SAR) and certificate of conformance requirements. The intent of this paper is to identify opportunities for improving the outcome of future projects and to mitigate fabrication challenges proactively. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
NASA NTRS1983

Proceedings of the Flat-Plate Solar Array Project Research Forum on the Design of Flat-Plate Photovoltaic Arrays for Central Stations

The Flat Plate Solar Array Project, focuses on advancing technologies relevant to the design and construction of megawatt level central station systems. Photovoltaic modules and arrays for flat plate central station or other large scale electric power production facilities require the establishment of a technical base that resolves design issues and results in practical and cost effective configurations. Design, qualification and maintenance issues related to central station arrays derived from the engineering and operating experiences of early applications and parallel laboratory reserch activities are investigated. Technical issues are examined from the viewpoint of the utility engineer, architect/engineer and laboratory researcher. Topics on optimum source circuit designs, module insulation design for high system voltages, array safety, structural interface design, measurements, and array operation and maintenance are discussed.

Source record↗
NASA NTRS1989

The case for Mars III: Strategies for exploration - Technical

Papers on issues related to Mars exploration are presented, covering topics such as the social implications of manned missions to Mars, mission strategies, mission designs, the economics of a Mars mission, Space Station support for a Mars mission, a Diagnostic and Environmental Monitoring System, and a zero-g CELSS/recreation facility for an earth/Mars crew shuttle. Other topics include biomedical concerns and fitness in spaceflight, spaceflight environment habitability, the Mars Rover/Sample Return Mission, a rooitic Mars surface sampler, a Mars Orbiter, and scientific goals of Mars exploration. Additional topics include Space Station evolution, mission options, modeling advanced space systems, computer support for Mars missions, launch system options, advanced propulsion techniques, the utilization of resources on Mars, the development of a Martian base, and options for mobility on Mars.

Stoker, Carol R.↗
NASA NTRS1992

Unification - An international aerospace information issue

Scientific and Technical Information (STI) represents the results of large investments in research and development (R&D) and the expertise of a nation and is a valuable resource. For more than four decades, NASA and its predecessor organizations have developed and managed the preeminent aerospace information system. NASA obtains foreign materials through its international exchange relationships, continually increasing the comprehensiveness of the NASA Aerospace Database (NAD). The NAD is de facto the international aerospace database. This paper reviews current NASA goals and activities with a view toward maintaining compatibility among international aerospace information systems, eliminating duplication of effort, and sharing resources through international cooperation wherever possible.

Cotter, Gladys A.↗
NASA NTRS1995

A strategy for providing electronic library services to members of the AGATE Consortium

In November, 1992, NASA Administrator Daniel Goldin established a Task Force to evaluate conditions which have lead to the precipitous decline of the US General Aviation System and to recommend actions needed to re-establish US leadership in General Aviation. The Task Force Report and a report by Dr. Bruce J. Holmes, Manager of the General Aviation/Commuter Office at NASA Langley Research Center provided the directions for the formation of the Advanced General Aviation Transport Experiments (AGATE), a consortium of government, industry and university committed to the revitalization of the US General Aviation Industry. One of the recommendations of the Task Force Report was that 'a central repository of information should be created to disseminate NASA research as well as other domestic and foreign aeronautical research that has been accomplished, is ongoing or is planned... A user friendly environment should be created.' This paper describes technical and logistic issues and recommends a plan for providing technical information to members of the AGATE Consortium. It is recommended that the General Aviation office establish and maintain an electronic literature page on the AGATE server. This page should provide a user friendly interface to existing technical report and index servers identified in the report and listed in the Recommendations section. A page should also be provided which gives links to Web resources. A list of specific resources is provided in the Recommendations section. Links should also be provided to a page with tips on searching, a form to provide for feedback and suggestions from users for other resources. Finally, a page should be maintained which provides pointers to other resources like the LaRCsim workstation simulation software which is avail from LaRC at no cost. The developments of the Web is very dynamic. These developments should be monitored regularly by the GA staff and links to additional resources should be provided on the server as they become available. An recommendation to NASA Headquarters should be made to establish a logically central access to all of the NASA Technical Libraries, to make these resources available both to all NASA employees and to the AGATE Consortium.

Thompson, J. Garth↗
DOE OSTI2024

Mark-18A Cold Runs

The Savannah River National Laboratory (SRNL) is tasked by the National Nuclear Security Administration (NNSA) to recover highly valued isotopes from irradiated Mark-18A (Mk-18A) targets. The Savannah River Site (SRS) has sixty-five Mk-18A targets available for the recovery of the high valued materials. The sixty-five Mk-18A targets are currently stored in the L-Area Basin and will be removed one at a time and individually transported to SRNL. Upon receipt at SRNL, the Mk-18A target material will be removed from the confinement, dissolved, chemically separated, and calcined to a stable oxide. The flowsheet is designed to recover the plutonium as well as the trivalent actinides. The remaining unrecovered material will be discarded to the high activity drain (HAD) system in SRNL. A specially designed cask was procured for transport of the targets from L-Area to SRNL. Once received at SRNL, the targets will be loaded into the back of Cell 7 and resized as they enter the cell. The resized targets (1/4 lengths) will then be processed one at a time through the following processes: caustic dissolution and filtration; acidic dissolution and filtration, Reillex anion exchange, diglycolamide (DGA) cation exchange; and DGA calcination. This processing will result in two product streams. The first is an aqueous plutonium solution which will be removed from the shielded cells and taken to a glovebox for further purification and conversion to an oxide. The second is a calcined oxide containing the Am and Cm as well as other lanthanide fission products which will be removed from the shielded cells using a bagless transfer system. Both materials will be packaged for shipment to Oak Ridge National Laboratory (ORNL). All equipment to carry out this process was designed, procured or fabricated, and installed in a mock-up facility (716-4A) at SRS to allow for simulation testing in a non-radioactive area. This equipment was then dismantled and transferred from 716-4A to 773-A and installed in the SRNL Shielded Cells. After installation in the shielded cells facility testing was performed using water followed by surrogates and cold chemicals. Issues were identified during these evaluations, including equipment issues as well as technical challenges. Many of the issues were rectified during performance of the cold runs, and the remaining have a resolution identified. Table ES-1 provides a summary of all issues identified during the cold run operations, as well as the status and identified resolutions to outstanding issues.

07 ISOTOPE AND RADIATION SOURCES↗
NASA NTRS1990

Numerical Methods For Chemically Reacting Flows

Issues related to numerical stability, accuracy, and resolution discussed. Technical memorandum presents issues in numerical solution of hyperbolic conservation laws containing "stiff" (relatively large and rapidly changing) source terms. Such equations often used to represent chemically reacting flows. Usually solved by finite-difference numerical methods. Source terms generally necessitate use of small time and/or space steps to obtain sufficient resolution, especially at discontinuities, where incorrect mathematical modeling results in unphysical solutions.

Leveque, R. J.↗
NASA NTRSDate not supplied

A New Control Paradigm: Multiple Aircraft Controlled by Multiple Operators

Remotely piloted aircraft systems (RPAS) are becoming more and more prevalent in the aerospace operations. This is true in a number of diverse domains; urban air mobility, medical product delivery, infrastructure inspection, high altitude pseudo-satellites, search and rescue, auto cargo and several other applications. One aspect that all of these share in common is the need for scalability to be viable and continue to grow. The Association of Uncrewed Vehicle Systems International (AUVSI) develops an annual economic report. They project that in the first three years of integration more than 70,000 jobs will be created in the US alone, with an economic impact of more than $13.6 billion. This benefit will grow through 2025 when we foresee more than 100,000 jobs created and economic impact of $82 billion. For many of these domains to reach these levels and have the scalability needed, they will require a remote pilot to control multiple aircraft (1:N) or the extension of that, multiple pilots controlling multiple aircraft (m:N). This is a new control paradigm that raises multiple issues in various areas. The issues include regulatory, technical, safety, community acceptance and Human Factors. Human factors issues include displays, pilot workload, pilot situation awareness just to name a few. This panel brings together researchers, developers and operators that have been working in the area of m:N. They will discuss the need, the issues and some potential solutions.

multi-vehicle control↗
DOE OSTI2020

Demonstration of Integrated PostIrradiation Process Steps forMultikilogram Amounts of Low- and High-Burnup Used Nuclear Fuels

sponsored research and development (R&D) on the advanced, closed nuclear fuel cycle, including post-irradiation processing of used fuels, recovery of separated components, and preparation of recycle nuclear fuels. During the period 2007–2010, kilogram-scale demonstrations of the integrated processing steps were performed for actual light water reactor (LWR) used nuclear fuels (UNF). These integrated processing demonstrations were called “the Coupled-End-to-End” (CETE) campaigns and were associated with the Global Nuclear Energy Partnership program, which ran concurrently. The demonstrations were carried out in the shielded hot cells and associated gloveboxes located in the Irradiated Fuels Examination Laboratory (IFEL) and the Radiochemical Engineering Development Center (REDC) at the Oak Ridge National Laboratory (ORNL). Limited circulation program reports and a few technical papers were issued. The subject document provides a comprehensive summary of results, technical comparisons, and conclusions obtained from the demonstration campaigns and subsequent associated R&D.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2022

Providencia Island White Papers: Overview of Technical Requirements for Interconnection

This issue brief provides an overview of key technical requirements for inverter-based resources - including distributed energy resources (DERs) - to support the reliable and safe operation of the Providencia Island electrical grid, and other island or isolated area mini-grid applications. With the planned increase in inverter-based resources and the introduction of energy storage, adopting Institute of Electrical and Electronics Engineers (IEEE) Std 1547-2018, including the more advanced performance capabilities for voltage and frequency ride-through, will simplify interconnection as well as help to maintain a safe, reliable grid on Providencia Island.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2016

Genome editing in pluripotent stem cells: research and therapeutic applications

Recent progress in human pluripotent stem cell (hPSC) and genome editing technologies has opened up new avenues for the investigation of human biology in health and disease as well as the development of therapeutic applications. Gene editing approaches with programmable nucleases have been successfully established in hPSCs and applied to study gene function, develop novel animal models and perform genetic and chemical screens. Several studies now show the successful editing of disease-linked alleles in somatic and patient-derived induced pluripotent stem cells (iPSCs) as well as in animal models. Importantly, initial clinical trials have shown the safety of programmable nucleases for ex vivo somatic gene therapy. In this context, the unlimited proliferation potential and the pluripotent properties of iPSCs may offer advantages for gene targeting approaches. However, many technical and safety issues still need to be addressed before genome-edited iPSCs are translated into the clinical setting. Here, we provide an overview of the available genome editing systems and discuss opportunities and perspectives for their application in basic research and clinical practice, with a particular focus on hPSC based research and gene therapy approaches. Finally, we discuss recent research on human germline genome editing and its social and ethical implications. - Highlights: • Programmable nucleases have proven efficient and specific for genome editing in human pluripotent stem cells (hPSCs). • Genome edited hPSCs can be employed to study gene function in health and disease as well as drug and chemical screens. • Genome edited hPSCs hold great promise for ex vivo gene therapy approaches. • Technical and safety issues should be first addressed to advance the clinical use of gene-edited hPSCs.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2020

The Cost of (In-) Accurate Waste Characterization in the U.S. Nuclear Power Industry - 20066

Proper disposal of waste has never been a human priority. Our history is full of examples of throwing away things with minimal effort or thought to consequence. That is until disease or toxicity become apparent and we realize we need to change. Unfortunately, we almost never have all the information we need at the time we make decisions. In addition to the technical and scientific issues, profits and politics are also factors. Newton's third law also applies to politics and so for every policy (action) put in place, there will be (opposite reaction) forces in play to push back against it. These forces are seldom balanced and so the reaction to the discovery of harm is to over-correct and destroy the benefit to be had. This of course causes those who want the benefit, or profit from it, to work to undermine or repeal those measures put in place to eliminate the harm. The issue is exacerbated when the problem to be solved is highly technical and at the edge of our science so that the harm and benefit cannot be easily or accurately quantified. At these times, reason often goes out the window and our decision makers are influenced by either greed or fear as these emotions are much easier to stoke. Those of us in the middle, with the charge to 'do the right thing for the least cost', are therefore frequently constrained and forced into actions that are neither technically the right thing to do and not cost effective. The cost of radioactive waste disposal is based on the concentrations of various radioisotopes in the waste. Some of these isotopes are relatively easy to quantify and some are not. Most laboratory methods for quantification are limited in the amount of activity that can be present during the measurement process. Current nuclear plants were not designed with the idea that taking truly representative waste samples would be important. The limits used to define waste class and therefore cost are precisely defined but the methods for determining those concentrations are far less precise. Improving the accuracy of radioactivity concentrations in waste and having consistent and reasonable oversight can reduce waste costs through active management of the process. So what can we do about it? Science may provide an answer. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2016

A Review of Hydrogen/Halogen Flow Cells

Flow batteries provide an energy-storage solution for various grid-related stability and service issues that arise as renewable-energy-generation technologies are adopted. Among the most promising flow-battery systems are those using hydrogen/halogen redox couples, which promise the possibility of meeting the cost target of the US Department of Energy (DOE), due to their fast and reversible kinetics and low materials cost. However, significant critical issues and barriers for their adoption remain. In this review of halogen/hydrogen systems, technical and performance issues, and research and development progress are reviewed. The information in this review can be used as a technical guide for research and development of related redox-flow-battery systems and other electrochemical technologies.

25 ENERGY STORAGE↗
NASA NTRS2009

An Effective Health and Medical Technical Authority

The NASA Governance model directed the formation of three Technical Authorities, Engineering; Safety and Mission Assurance; and Health and Medical, to ensure that risks are identified and adjudicated efficiently and transparently in concert with the spaceflight programs and projects. The Health and Medical Technical Authority (HMTA) has been implemented at the Johnson Space Center (JSC) and consists of the Chief Medical Office (CMO), the Deputy CMO, and HMTA Delegates. The JSC HMTA achieves the goals of risk identification and adjudication through the discharge of the appropriate technical expertise to human space flight programs and projects and the escalation of issues within program and technical authority boards. The JSC HMTA relies on subject matter experts (SMEs) in the Space Life Sciences Directorate at JSC as well as experts from other Centers to work crew health and performance issues at the technical level, develop requirements, oversee implementation and validation of requirements, and identify risks and non-compliances. Once a risk or potential noncompliance has been identified and reported to the programs or projects, the JSC HMTA begins to track it and closely monitor the program's or project's response. As a risk is developed or a non-compliance negotiated, positions from various levels of decision makers are sought at the program and project control boards. The HMTA may support a program or project position if it is satisfied with the decision making and vetting processes (ex. the subject matter expert voiced his/her concerns and all dissenting opinions were documented) and finds that the position both acknowledges the risk and cost of the mitigation and resolves the issue without changing NASA risk posture. The HMTA may disagree with a program or project position if the NASA risk posture has been elevated or obfuscated. If the HMTA does disagree with the program or project position, it will appeal to successively higher levels of authority so that risk acceptance and risk trades will be acknowledged and sanctioned at the highest appropriate level; this includes Program Managers, Mission Directorate Associate Administrators and the Agency Administrator.

Fogarty, Jennifer A.↗
NASA NTRS2020

Recurring Causes of Human Spaceflight Mishaps during Flight Tests and Early Operations

n analysis of recurring causes underlying human spaceflight mishaps that occurred during flight tests and early operations was performed. Eight mishaps from the Apollo, Soyuz, Skylab, Space Shuttle, and Constellation Programs (i.e., the Ares-1X test flight) and commercial suborbital systems were included in the study. Detailed event analyses were performed for the historical mishaps and aggregate data analyses conducted to identify recurring issues. The nine most frequent issues were inadequate technical controls or risk management practices, incomplete procedures, system design and development issues, inadequate inspection or secondary verification requirements, failures of organizations to learn from previous incidents, inadequate schedule controls, inadequate task analyses or design processes, flaws in the design of organizations, and issues with organizational safety cultures.

Timothy S Barth↗
NASA NTRSDate not supplied

Recurring Causes of Human Spaceflight Mishaps During Flight Tests and Early Operations

An analysis of recurring causes underlying human spaceflight mishaps that occurred during flight tests and early operations was performed. Eight mishaps from the Apollo, Soyuz, Skylab, Space Shuttle, and Constellation Programs (i.e., the Ares-1X test flight) and early commercial suborbital operations were included in the study. Detailed event analyses were performed for the historical mishaps and aggregate data analyses conducted to identify recurring issues. The nine most frequent issues were inadequate technical controls or risk management practices, incomplete procedures, system design and development issues, inadequate inspection or secondary verification requirements, failures of organizations to learn from previous incidents, inadequate schedule controls, inadequate task analyses or design processes, flaws in the design of organizations, and issues with organizational safety cultures.

Human Spaceflight↗
NASA NTRS2010

Aeroelasticity Benchmark Assessment: Subsonic Fixed Wing Program

The fundamental technical challenge in computational aeroelasticity is the accurate prediction of unsteady aerodynamic phenomena and the effect on the aeroelastic response of a vehicle. Currently, a benchmarking standard for use in validating the accuracy of computational aeroelasticity codes does not exist. Many aeroelastic data sets have been obtained in wind-tunnel and flight testing throughout the world; however, none have been globally presented or accepted as an ideal data set. There are numerous reasons for this. One reason is that often, such aeroelastic data sets focus on the aeroelastic phenomena alone (flutter, for example) and do not contain associated information such as unsteady pressures and time-correlated structural dynamic deflections. Other available data sets focus solely on the unsteady pressures and do not address the aeroelastic phenomena. Other discrepancies can include omission of relevant data, such as flutter frequency and / or the acquisition of only qualitative deflection data. In addition to these content deficiencies, all of the available data sets present both experimental and computational technical challenges. Experimental issues include facility influences, nonlinearities beyond those being modeled, and data processing. From the computational perspective, technical challenges include modeling geometric complexities, coupling between the flow and the structure, grid issues, and boundary conditions. The Aeroelasticity Benchmark Assessment task seeks to examine the existing potential experimental data sets and ultimately choose the one that is viewed as the most suitable for computational benchmarking. An initial computational evaluation of that configuration will then be performed using the Langley-developed computational fluid dynamics (CFD) software FUN3D1 as part of its code validation process. In addition to the benchmarking activity, this task also includes an examination of future research directions. Researchers within the Aeroelasticity Branch will examine other experimental efforts within the Subsonic Fixed Wing (SFW) program (such as testing of the NASA Common Research Model (CRM)) and other NASA programs and assess aeroelasticity issues and research topics.

Florance, Jennifer P.↗