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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 325 records · Page 18

Feasibility study of oxygen-dispensing emitters for thermionic converters, phase 1

A metal/ceramic Marchuk tube was used to measure work functions of oxygen-doped tantalum, to determine applicability of the material to plasma-mode thermionic converters. Oxygen-doped tantalum was shown to increase in work function monotonically with oxygen doping in the range 0.1 to 0.3 atomic percent. Oxygenated test emitters were run at an average temperature of 2165 K and a T/T sub Cs ratio -5.8 to observe the influence of oxygen depletion. Bare work function decreased with outgassing of oxygen. Projections were made based on outgassing kinetics and area/volume ratios to calculate the longevity of oxygen doping in a practical converter. Calculations indicated that the program goal of 10,000 hr could be achieved at 1800 K with an initial oxygen doping of 1 atomic percent and a practical emitter area/volume ratio.

Desteese, J. G.↗

Soils Activity Quality Assurance Plan, Revision 1

This Quality Assurance Plan (QAP) provides the overall Quality Assurance (QA) program requirements, technical planning, and general quality practices to be applied to the U.S. Department of Energy (DOE) Environmental Management (EM) Nevada Program Soils Activity. The QAP requirements are consistent with the Quality Systems for Environmental Data and Technology Programs–Requirements with Guidance for Use (ANSI/ASQ, 2004); the Intergovernmental Data Quality Task Force Uniform Federal Policy for Quality Assurance Project Plans (IDQTF, 2005); and 10 Code of Federal Regulations (CFR) 830.120, Quality Assurance (CFR, 2017a), which apply to specific activities performed under the Soils Activity. The EM Nevada Program owns and is responsible for maintaining this QAP. Individual participants are responsible for implementing the requirements of this QAP in accordance with their own approved programs, processes, plans, and procedures. If a participant’s requirement document differs from this QAP, the stricter requirement will take precedence.

54 ENVIRONMENTAL SCIENCES↗

Issue focused stakeholder collaboration: reaching consensus on spent nuclear fuel transportation operational practices - 15465

This paper examines stakeholder and issue-focused approaches used by Department of Energy (DOE) programs to collaborate with key stakeholders on transportation practices to ship radioactive material, particularly used nuclear fuel (UNF) and transuranic waste (TRU). In accordance with the Administration's Strategy for the Management and Disposal of Used Nuclear Fuel and High-Level Radioactive Waste, the current effort by DOE to plan for the development of a future transportation system to ship UNF from commercial reactors, with an initial focus on shutdown reactors, is using approaches similar to those used in other successful shipping campaigns to collaborate with stakeholders about sustainable transportation practices. As part of a coordinated approach to stakeholder outreach and collaboration, DOE is currently developing a draft Transportation Planning Framework to provide a template for future shipments of UNF from commercial reactors and is engaged with states and tribes and other stakeholders in discussions on the institutional and operational components of that Framework. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Steel–Concrete Composite Pressure Vessels for Hydrogen Storage at High Pressures

The need to store large quantities of hydrogen in large diameter steel vessels under high pressures results in shell thicknesses that are too large to produce by most steel mills and not practical to fabricate. Accordingly, a research program was undertaken by Oak Ridge National Laboratory to develop a new concept of combining steel with concrete to construct such vessels economically and practically. The concept is to fabricate vessels where the steel shell thickness is approximately one half that required to resist the hoop forces due to internal pressure. As such, the steel shell is designed to carry the full amount of the longitudinal forces in the vessel but only one half of the hoop loads due to internal pressure. The other half of the hoop loads is carried by a prestressed and reinforced concrete shell. In large diameter vessels, the cost of the shell can further be reduced by using layered steel shell construction rather than solid-wall construction. Such shell construction has also the added advantage of easily venting the hydrogen that permeates through the steel shell directly to the atmosphere through vent holes. This mechanism prevents the hydrogen from damaging the steel shell. The theoretical formulation of the steel concrete shell design is presented in this paper. Finally, in addition, details of a full-scale mock up vessel designed, fabricated, and tested to prove the proposed methodology are given.

42 ENGINEERING↗

Determinants of enrollment in public incentive programs for forest management and their effect on future programs for woody bioenergy: evidence from Virginia and Texas

Several federal- and state-sponsored programs, including cost-sharing arrangements, tax incentives, and technical assistance programs, are available to forestland owners, aiming to encourage desired forest management practices and outcomes. However, enrollment rates in such programs are low, and trends of forestland parcelization hint at an even smaller enrollment rate in the future. Therefore, it is important to understand how socioeconomic attributes of forestland owners and past experience with such programs affect the likelihood of enrollment in public incentive programs. Among others, this will help us provide tailored information to forestland owners who are less likely to use these opportunities through extension and outreach programs. Towards this end, we conducted a survey of 1800 forestland owners in Virginia and Texas. Our recursive partitioning, logistic regression, and Cochran–Armitage trend test results suggest that forestland owners who are less likely to enroll in such programs have relatively smaller forestland acreage, a lower level of education, and shorter land ownership tenure. We also find that forestland owners with experience in public incentive programs tend to attach higher importance to potential programs, including those that do not directly benefit them. Furthermore, we also identify threshold values for explanatory variables such as acreage and tenure length.

54 ENVIRONMENTAL SCIENCES↗

Semi-Automated Diagnosis, Repair, and Rework of Spacecraft Electronics

NASA's Constellation Program for Exploration of the Moon and Mars places human crews in extreme isolation in resource scarce environments. Near Earth, the discontinuation of Space Shuttle flights after 2010 will alter the up- and down-mass capacity for the International Space Station (ISS). NASA is considering new options for logistics support strategies for future missions. Aerospace systems are often composed of replaceable modular blocks that minimize the need for complex service operations in the field. Such a strategy however, implies a robust and responsive logistics infrastructure with relatively low transportation costs. The modular Orbital Replacement Units (ORU) used for ISS requires relatively large blocks of replacement hardware even though the actual failed component may really be three orders of magnitude smaller. The ability to perform in-situ repair of electronics circuits at the component level can dramatically reduce the scale of spares and related logistics cost. This ability also reduces mission risk, increases crew independence and improves the overall supportability of the program. The Component-Level Electronics Assembly Repair (CLEAR) task under the NASA Supportability program was established to demonstrate the practicality of repair by first investigating widely used soldering materials and processes (M&P) performed by modest manual means. The work will result in program guidelines for performing manual repairs along with design guidance for circuit reparability. The next phase of CLEAR recognizes that manual repair has its limitations and some highly integrated devices are extremely difficult to handle and demand semi-automated equipment. Further, electronics repairs require a broad range of diagnostic capability to isolate the faulty components. Finally repairs must pass functional tests to determine that the repairs are successful and the circuit can be returned to service. To prevent equipment demands from exceeding spacecraft volume capacity and skill demands from exceeding crew time and training limits, the CLEAR project is examining options provided by non-real time tele-operations, robotics, and a new generation of diagnostic equipment. This paper outlines a strategy to create an effective repair environment where, with the support of ground based engineers, crewmembers can diagnose, repair and test flight electronics in-situ. This paper also discusses the implications of successful tele-robotic repairs when expanded to rework and reconfiguration of used flight assets for building Constellation infrastructure elements.

Struk, Peter M.↗

Scalability and Effectiveness of Smart Charge Management

The rise in electric vehicle (EV) adoption presents growing challenges for power grids, particularly from simultaneous residential charging, which can cause voltage fluctuations and increase feeder peak loads. Baltimore Gas and Electric (BGE), with support from the U.S. Department of Energy, initiated a pilot program to evaluate managed residential EV charging through Smart Charge Management (SCM). This study analyzes real-world charging behavior data from the pilot and feeder-level base loads from BGE to simulate residential charging scenarios through 2035 across the Washington, DC–Baltimore region. Grid impacts under unmanaged charging are compared to three SCM strategies: TOU-immediate, TOU-distributed, and Load Balancing. Results show that the magnitude of peak reduction is highly feeder-dependent. Some feeders achieve reductions of more than 40% at high enrollment levels, while others show improvements closer to 10–15%. This heterogeneity reflects differences in baseline feeder load shapes, EV penetration, and plug-in behavior across customers. Results also highlight trade-offs between shifting load away from peak periods and minimizing secondary demand peaks, offering practical insights for future utility program design.

Electric vehicle↗

Working on the Boundaries: Philosophies and Practices of the Design Process

While systems engineering process is a program formal management technique and contractually binding, the design process is the informal practice of achieving the design project requirements throughout all design phases of the systems engineering process. The design process and organization are systems and component dependent. Informal reviews include technical information meetings and concurrent engineering sessions, and formal technical discipline reviews are conducted through the systems engineering process. This paper discusses and references major philosophical principles in the design process, identifies its role in interacting systems and disciplines analyses and integrations, and illustrates the process application in experienced aerostructural designs.

Ryan, R.↗

Comparison of the performance of TLD, OSL and RPL personal dosimetry systems to the American National Standard Institute (ANSI) test categories

The Laboratory Accreditation Program (LAP) tests the capability and performance of the United States Department of Energy's (USDOE) facilities to accurately measure and quantify the whole-body and extremity radiation equivalent doses to the occupational workers. The dosimetry methods used in personal dosimetry can be Thermoluminescence (TL), Optically Stimulated Luminescence (OSL) and Radiophotoluminescence (RPL), among other techniques available. Currently, the TL (LiF:Mg,Ti) and OSL (Al 2 O 3 :C) dosimetry systems are DOELAP-accredited for occupational dose measurements and regulatory reporting. In this study, the performance of a beryllium oxide (BeO) OSL dosimetry system and of a silver-doped phosphate glass RPL dosimetry system is compared against the performance of an accredited LiF:Mg,Ti TL dosimetry system. The bias and standard deviation in each of the performance test categories are compared between these three systems for exposures to photons, beta, and mixed radiation fields with the criteria established by the American National Standard Institute (ANSI) and Health Physics Society (HPS) N13.11-2022 standard. The practical implementation of the dosimetry program and its equivalency to the occupational personal equivalent dose H p (0.07) and H p (10) measurements were evaluated. The TL, OSL and RPL dosimetry systems passed the ANSI performance test criteria for H p (0.07) and H p (10) occupational dose measurements and met the DOELAP accreditation requirements.

61 RADIATION PROTECTION AND DOSIMETRY↗

Review of the Space Applications program, 1974

The purpose of this review is to provide the participants in the National Aeronautics and Space Administration/National Academy of Engineers' Summer Study in Applications a concise overview of the NASA Applications Program as it stands in 1974. The review covers the accomplishments of the various discipline-oriented programs that make up the total Applications Program, discusses the program plan for the 1975 to 1980 period, and examines the anticipated spaceflight capabilities of the 1980's. NASA has requested the National Academy of Engineers to conduct through its Space Applications Board a comprehensive study of the future Space Applications Program encompassing the following: (1) the Applications Program in general, with particular emphasis on practical approaches, including assessment of the socio-economic benefits and (2) how the broad comprehensive program envisioned above influences, or is influenced by, the shuttle system, the principal space transport system of the 1980's.

Source record↗

Report on Thermal Cycling Testing and Bimaterial Weld Development for a Passively Actuated Materials Surveillance Test Article

This report describes the continuation and conclusion of a thermal cycling test program designed to evaluate a family of passively actuated material surveillance test articles. Additionally, the report details a preliminary study of bimetallic welding between 316 stainless steel and TZM (tungsten-zirconium-molybdenum) alloy. The test program was ultimately successful in demonstrating the basic viability of the passively actuated test article concept as well as specifically validating the procedures developed to size specimens to mimic the mechanical response of operating components. The report discusses and summarizes the results of the complete test program which tested samples for more than 1,000 controlled thermal cycles. The weld development program included both stir friction and electron beam joining. The stir friction welding was ultimately successful, while the electron beam welding would require additional development. Ultimately, these test programs pave the way for implementing a materials surveillance program in future molten salt reactors (MSRs). The report conclusions outline a plan for transforming the research and developed described here into a definite set of practices and procedures for a surveillance program at a future operating reactor.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗

Implementing a Reliability Centered Maintenance Program at NASA's Kennedy Space Center

Maintenance practices have long focused on time based "preventive maintenance" techniques. Components were changed out and parts replaced based on how long they had been in place instead of what condition they were in. A reliability centered maintenance (RCM) program seeks to offer equal or greater reliability at decreased cost by insuring only applicable, effective maintenance is performed and by in large part replacing time based maintenance with condition based maintenance. A significant portion of this program involved introducing non-intrusive technologies, such as vibration analysis, oil analysis and I/R cameras, to an existing labor force and management team.

DIAGNOSTIC EQUIPMENT↗

An Evaluation of Army Wellness Center Clients’ Health-Related Outcomes

Purpose: To examine whether Army community members participating in a best-practice based workplace health promotion program (WHPP) experience goal-moderated improvements in health-related outcomes. Design: Pretest/posttest outcome evaluation examining an autonomously participating client cohort over 1 year. Setting: Army Wellness Center facilities on 19 Army installations. Participants: Army community members sample (N = 5703), mostly Active Duty Soldiers (64%). Intervention: Assessment of health risks with feedback, health assessments, health education classes, and health coaching sessions conducted by health educators at a recommended frequency of once a month for 3 to 12 months. Measures: Initial and follow-up outcome assessments of body mass index (BMI), body fat, cardiorespiratory fitness, blood pressure, and perceived stress. Analysis: Mixed model linear regression testing for goal-moderated improvements in outcomes. Results: Clients experienced significant improvements in body fat (−2% change), perceived stress (−6% to −12% change), cardiorespiratory fitness (+6% change), and blood pressure (−1% change) regardless of health-related goal. Only clients with a weight loss goal experienced BMI improvement (−1% change). Follow-up outcome assessment rates ranged from 44% (N = 2509) for BMI to 6% (N = 342) for perceived stress. Conclusion: Army Wellness Center clients with at least 1 follow-up outcome assessment experienced improvements in military readiness correlates and chronic disease risk factors. Evaluation design and follow-up-related limitations notwithstanding results suggest that best practices in WHPPs can effectively serve a globally distributed military force.

Rivera, L. Omar↗

Practices for Demonstrating Energy Savings from Commercial PACE Projects

Nearly three-fourths of U.S. states have authorized local governments to use voluntary special assessments on commercial properties to finance energy improvements that boost economic development, create jobs, increase property values and advance energy goals. Commercial Property Assessed Clean Energy (C-PACE) financing allows building owners to repay the borrowed capital — from private or public sources — over time using their property as security. Berkeley Lab is supporting the Department of Energy’s Commercial PACE Working Group by developing a series of C-PACE issue briefs. The second brief in this series, Practices for Demonstrating Energy Savings from Commercial PACE Projects, looks at common practices for demonstrating energy savings to support state and local governments that sponsor C-PACE programs and want to track their energy impacts. This brief reviews: -The value proposition and trade-offs of conducting energy impact assessments for C-PACE programs; -Methods to quantify energy savings impacts from energy efficiency building improvements; and -Available resources and tools to support energy impact assessments. C-PACE programs may benefit from energy impact assessments for many reasons, including: -Validating the public benefits of the programs -Demonstrating that C-PACE can deliver participant benefits -Illustrating program impacts on public policy goals -Generating data to help improve program performance Many C-PACE programs are collecting data on project energy savings impacts, and these data can be leveraged to further support decision making and program implementation. Potential drawbacks to energy impact assessments may include added cost and burdens on property owners (e.g., the need to collect building energy consumption data). Where these burdens are considerable, they might slow program uptake. State and local governments can balance the benefits of energy impact assessments with the range of costs and accuracy inherent to available assessment methodologies. Additionally, depending on the policy context in the state or local government, a C-PACE program may be able to leverage existing efforts (e.g., building energy benchmarking programs) to reduce impact assessment costs, align with building owner practices and expectations, and efficiently assess program impact.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Developing a Supply Chain Security Program

Amid growing concerns over foreign manufacturing for components and devices deployed in critical energy infrastructure, this research from the national labs will highlight best practices for developing and maintaining a supply chain security program. Tools for asset inventory, tips for developing and maintaining software- and hardware-bills-of-materials (SBOMs and HBOMs), recommended contractual language for vendor agreements, and identification of responsibilities will be shared. We discuss the one-time requirements to enable a successful supply chain security program and the best ways to operationalize this program for maximum impact, including development of robust practices for vulnerability tracking, patch management, and workarounds, with understanding of the reliability and uptime requirements for utilities. The recommendations shared are based on a cyber-informed engineering approach to identification of high-consequence impacts and the engineering controls related to supply chain management that can best mitigate these impacts. This approach allows for prioritization of resources. Additionally, we highlight relative up-front and ongoing costs associated with recommended controls. Viewers will leave with an understanding what a supply chain security program is, and what steps, prioritized for resource-constrained organizations, can build a robust program.

14 SOLAR ENERGY↗

Several Small or Single Large? Quantifying the Catchment-Wide Performance of On-Site Wastewater Treatment Plants with Inaccurate Sensors

On-site wastewater treatment plants (OSTs) often lack monitoring, resulting in unreliable treatment performance. They thus appear to be a stopgap solution despite their potential contribution to circular water management. Low-maintenance but inaccurate soft sensors are emerging that address this concern. However, how their inaccuracy impacts the catchment-wide treatment performance of a system of many OSTs has not been quantified. Here, we develop a stochastic model to estimate catchment-wide OST performances with a Monte Carlo simulation. In our study, soft sensors with a 70% accuracy improved the treatment performance from 66% of the time functional to 98%. Soft sensors optimized for specificity, indicating the true negative rate, improve the system performance, while sensors optimized for sensitivity, indicating the true positive rate, quantify the treatment performance more accurately. This new insight leads us to suggest programming two soft sensors in practical settings with the same hardware sensor data as input: one soft sensor geared to high specificity for maintenance scheduling and one geared to high sensitivity for performance quantification. Our findings suggest that a maintenance strategy combining inaccurate sensors with appropriate alarm management can vastly improve the mean catchment-wide treatment performance of a system of OSTs.

54 ENVIRONMENTAL SCIENCES↗