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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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All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

Source-to-Source Automatic Differentiation of OpenMP Parallel Loops

This article presents our work toward correct and efficient automatic differentiation of OpenMP parallel worksharing loops in forward and reverse mode. Automatic differentiation is a method to obtain gradients of numerical programs, which are crucial in optimization, uncertainty quantification, and machine learning. The computational cost to compute gradients is a common bottleneck in practice. For applications that are parallelized for multicore CPUs or GPUs using OpenMP, one also wishes to compute the gradients in parallel. Here, we propose a framework to reason about the correctness of the generated derivative code, from which we justify our OpenMP extension to the differentiation model. We implement this model in the automatic differentiation tool Tapenade and present test cases that are differentiated following our extended differentiation procedure. Performance of the generated derivative programs in forward and reverse mode is better than sequential, although our reverse mode often scales worse than the input programs.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2017

Nuclear power plant risk-informed surveillance frequency control program implementation at the Duke Catawba nuclear plant with a focus on instrumentation and control systems - 333

This paper summarizes an updated process for risk-informed surveillance frequency control program (SFCP) implementation at the Catawba Nuclear Power Plant in the past year. This program includes selection and prioritization of specific target surveillance test interval extensions; and development, review, and implementation of surveillance test risk informed documented evaluation (STRIDE) packages designed to support extension of conventional surveillance requirement test intervals, in accordance with 'Risk-Informed Technical Specifications Initiative 5b, Risk-Informed Method for Control of Surveillance Frequencies, Industry Guideline,' NEI 04-10, Revision 1 . The scope of work associated with STRIDE development includes probabilistic risk assessment (PRA) case studies, deterministic assessment (DA) evaluations, and, where required, instrument drift evaluation (IDE). The STRIDE implementation efforts have also included support of independent decision-making panel (IDP) meetings at the implementing power stations and IDP member training. The purpose of this paper is to provide a presentation of a refined process for STRIDE development with a focus on instrumentation and control systems based on author experience, which includes support for the development of multiple STRIDE packages for the Catawba Nuclear Plant. This paper outlines a framework for practical implementation of an SFCP within the context of an integrated risk-informed performance-based regulation application program with emphasis on instrumentation and control systems. (authors)

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
DOE OSTI2022

A computationally efficient algorithm for computing convex hull prices

Electricity markets worldwide allow participants to bid non-convex production offers. While non-convex offers can more accurately reflect a resource's capabilities, they create challenges for market clearing processes. For example, system operators may be required to execute side payments to participants whose costs are not covered through energy sales as determined via traditional locational marginal pricing schemes. Convex hull pricing minimizes this and other types of side payments while providing uniform (i.e., locationally and temporally consistent) prices. Computing convex hull prices involves solving either a large-scale linear program or the Lagrangian dual of the corresponding non-convex scheduling problem. Further, the former approach requires explicit descriptions of market participants' convex hulls. While linear programs for computing convex hull prices are large, their structure is naturally decomposable by generators. Here, in this work, we propose and empirically analyze a Benders decomposition approach to computing convex hull prices that leverages recent advances in convex hull formulations for thermal generating units. We demonstrate across a large set of test instances that our decomposition approach only requires modest computational effort, obtaining solutions at least an order of magnitude faster than the equivalent large-scale linear programming approach. Overall, we provide a computationally feasible method for computing convex hull prices for industrial scale market clearing problems, enabling the possibility of practical adoption of this advanced pricing mechanism.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2017

Updated Stormwater Management Program Plan: For coverage under the National Pollutant Discharge Elimination System Municipal Separate Storm Sewer System Permit for stormwater discharges within the Middle Rio Grande Watershed (v.3)

The SWMPP describes the best management practices (BMPs) employed at SNL, measurable goals, and anticipated implementation dates for compliance with the Permit requirements to ensure that stormwater discharges from the SNL MS4 do not contribute pollutants to Waters of the United States (WOTUS), namely the Tijeras Arroyo and the Rio Grande. The SWMPP is updated annually, and as necessary, to include new information and/or document the development, implementation and assessment of program elements, as required in Part III.B of the Permit. Version 3 of the SWMPP documents compliance activities and program elements developed and implemented between July 1, 2016 and June 30, 2017; it is required to be submitted on or before December 1, 2017.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
NASA NTRS2018

Aeronautics Autonomy Testbed Capability (AATC) Team Developed Concepts

In 2015, the National Aeronautics and Space Administration (NASA) formed a multi-center, interdisciplinary team of engineers from three different aeronautics research centers who were tasked with improving NASA autonomy research capabilities. This group was subsequently named the Aeronautics Autonomy Testbed Capability (AATC) team. To aid in confronting the autonomy research directive, NASA contracted IDEO, a design firm, to provide consultants and guides to educate NASA engineers through the practice of design thinking, which is an unconventional method for aerospace design processes. The team then began learning about autonomy research challenges by conducting interviews with a diverse group of researchers and pilots, military personnel and civilians, experts and amateurs. Part of this design thinking process involved developing ideas for products or programs known as concepts that could enable real world fulfillment of the most important latent needs identified through analysis of the interviews. The concepts are intended to be sacrificial, intermediate steps in the design thinking process and are presented in this report to record the efforts of the AATC group. Descriptions are provided in present tense to allow for further ideation and imagining the concept as reality as was attempted during the teams discussions and interviews. This does not indicate that the concepts are actually in practice within NASA though there may be similar existing programs independent of AATC. These concepts were primarily created at two distinct stages during the design thinking process. After the initial interviews, there was a workshop for concept development and the resulting ideas are shown in this work as from the First Round. As part of succeeding interviews, the team members presented the First Round concepts to refine the understanding of existing research needs. This knowledge was then used to generate an additional set of concepts denoted as the Second Round. Some concepts were created by a single person in a few minutes while others were refined by the entire team over several weeks. Thus, certain ideas are more detailed than others but those from the second round are not necessarily more comprehensive than the first round concepts. Primarily, as reported here in the Second Round section, the designs serve to encompass more of the high level end user research needs which were not necessarily known to the team during the prior workshop. In the figures provided throughout this report, illustrations are often provided to represent a concept. Nearly all of the images are informal sketches or renderings and this casualness should, hopefully, not be held to negate the potential insights available within the concepts.

Smith, Phillip J.↗
DOE OSTI2021

ESPC ESA Webinar Series: ESPC IDIQ Contract Vehicle Overview

This webinar provides instructions and resources for financing distributed energy projects (e.g. on-site renewable energy, storage, and combined heat and power) using an energy savings performance contract (ESPC) energy sales agreement (ESA) through the U.S. Department of Energy (DOE) indefinite-delivery, indefinite-quantity (IDIQ) energy savings performance contract (ESPC) vehicle. The DOE IDIQ ESPC contract vehicle uses a streamlined master contract that allows federal agencies to work with 21 energy service companies holding the current DOE IDIQ ESPC. Topics covered in the webinar include: An overview of the DOE IDIQ contract vehicle; ESA-specific considerations for IDIQ contracts; and Specific use cases. The webinar also provides an overview of the resources available on the Federal Energy Management Program website, such as IDIQ tools and templates. This webinar is the fifth in a series that provides information, best practices, and resources for implementing an ESPC ESA project. ESPC ESAs are a great option for federal sites that are motivated to reduce site costs, have no capital investment funding, and cannot use the U.S. Department of Defense 10 USC 2922a authority for long-term contracting.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2025

Connecting Minds: AI Use Cases to Bridge Power Systems and Large Language Models for Practical Applications

Recent advances in artificial intelligence (AI) and development of large language models (LLMs) present the opportunity to develop a new generation of power systems applications. In contrast with early power system AI applications based on structured numerical data, LLMs offer unique capabilities to perform logical reasoning using text documents, unstructured data, and application programming interface (API) calls to computational software. This paper seeks to bridge the knowledge gap between power systems engineers and LLM developers through a crosscutting explanation of use cases, characteristics, requirements, practical considerations from the perspectives of both LLM capabilities and industry needs. Specific focus is given to applications that can be realistically deployed by electric utilities. After introducing the architecture of LLMs and unique challenges of the power systems domain, this paper proposes twenty representative LLM applications grouped into categories of 1) power system operations, 2) asset management, 3) system planning and analytics, and 4) energy management and protection systems. Five use cases are presented within each category with descriptions of the motivation, objectives, approaches, example inputs / outputs, and benefits of each use case.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2022

Noisy-Intermediate-Scale Quantum Electromagnetic Transients Program

Quantum-empowered electromagnetic transients program (QEMTP) is a promising paradigm for tackling EMTP's computational burdens. Nevertheless, no existing studies truly achieve a practical and scalable QEMTP operable on today's noisy-intermediate-scale quantum (NISQ) computers. The strong reliance on noise-free and fault-tolerant quantum devices--which appears to be decades away--hinder practical applications of current QEMTP methods. Here, we devise a NISQ-QEMTP methodology which for the first time transitions the QEMTP operations from ideal, noise-free quantum simulators to real, noisy quantum computers. The main contributions lie in: (1) a shallow-depth QEMTP quantum circuit for mitigating noises on NISQ quantum devices; (2) practical QEMTP linear solvers incorporating executable quantum state preparation and measurements for nodal voltage computations; (3) a noise-resilient QEMTP algorithm leveraging quantum resources logarithmically scaled with power system dimension; (4) a quantum shifted frequency analysis (QSFA) for accelerating QEMTP by exploiting dynamic phasor simulations with larger time steps; (5) a systematical analysis on QEMTPs performance under various noisy quantum environments. Extensive experiments systematically verify the accuracy, efficacy, universality and noise-resilience of QEMTP on both noise-free simulators and IBM real quantum computers.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2016

Sampling Low-Level Waste - Building a Program - 16101

Low level radioactive waste is routinely sampled and analyzed to demonstrate compliance with Title 10 Code of Federal Regulations Part 61. The sample results are frequently used to create scaling factors to relate the activity of hard to detect (HDT) radionuclides to gamma emitting activity if there is a correlation between the key and scaled radionuclide pair. The activity of gamma emitters can be used with these scaling factors to calculate activity of the low level waste generated in the plant. Another method is to use the sample results directly and scale the total activity to the volume or weight of the waste in the container. Either method assumes that the sample results are representative of the total waste in the container. This requires that the waste streams be accurately defined and that the samples contain radionuclides at ratios that are representative of the bulk waste. This is not always the case and deviations between the sample results and the actual radionuclide concentrations in the waste can lead to miss-classification of the waste resulting in regulatory non-compliance, increased waste disposal costs or both. A deliberate sampling methodology that considers the context of the waste generation and the inherent limitations in practical sampling methodologies will enhance the licensee's ability to demonstrate the analytical results from the sample are representative and defendable. A good sampling program starts with the establishment of waste streams that are consistent with both production mechanisms and plant systems. Once waste streams have been established, data quality objectives can be determined and then the methods for obtaining an appropriate sample can be developed along with the identification of sample points and sample schedules. Sometimes it may not be practical or even possible to obtain a truly representative sample in which case the results from the measurement of the sample must be evaluated within the context of the expected values and the factors inhibiting the collection of a truly representative sample. This paper will explore objectives of a sampling program in relation to the regulations and identify methods that can be used to obtain and evaluate sample data that can be defended as 'representative'. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
NASA NTRS2011

Long-Term International Space Station (ISS) Risk Reduction Activities

As the assembly of the ISS nears completion, it is worthwhile to step back and review some of the actions pursued by the Program in recent years to reduce risk and enhance the safety and health of ISS crewmembers, visitors, and space flight participants. While the initial ISS requirements and design were intended to provide the best practicable levels of safety, it is always possible to further reduce risk given the determination, commitment, and resources to do so. The following is a summary of some of the steps taken by the ISS Program Manager, by our International Partners, by hardware and software designers, by operational specialists, and by safety personnel to continuously enhance the safety of the ISS, and to reduce risk to all crewmembers. While years of work went into the development of ISS requirements, there are many things associated with risk reduction in a Program like the ISS that can only be learned through actual operational experience. These risk reduction activities can be divided into roughly three categories: Areas that were initially noncompliant which have subsequently been brought into compliance or near compliance (i.e., Micrometeoroid and Orbital Debris [MMOD] protection, acoustics) Areas where initial design requirements were eventually considered inadequate and were subsequently augmented (i.e., Toxicity hazard level-4 materials, emergency procedures, emergency equipment, control of drag-throughs) Areas where risks were initially underestimated, and have subsequently been addressed through additional mitigation (i.e., Extravehicular Activity [EVA] sharp edges, plasma shock hazards). Due to the hard work and cooperation of many parties working together across the span of more than a decade, the ISS is now a safer and healthier environment for our crew, in many cases exceeding the risk reduction targets inherent in the intent of the original design. It will provide a safe and stable platform for utilization and discovery for years to come.

Forroci, Michael P.↗
NASA NTRS2018

History and Archives Contribute to the Success of Space Flight Programs

Final Paper, not the Abstract, is attached: This report discusses how history can be used by management, engineering, and operations personnel within space flight programs. Works by professional historians and sociologists inform key decision makers and policy specialists on lessons learned from space flight program management successes and failures, as well as from legislative affairs, policy making, and commercial space efforts. Vehicle engineering history written by engineers for an engineering or operations audience informs project management and technical personnel on lessons learned, best practices, and the rationale behind the design and operation of flight vehicles and supporting ground systems. Archives play a critical role in supporting the efforts of both professional historians and flight program personnel. Suggestions are made concerning how professional historians could leverage the interests and knowledge of flight program personnel to obtain more insight that is needed to support historical research efforts.

Archive↗
DOE OSTI2015

Investigation of criticality safety control infraction data at a nuclear facility

Chemical and metallurgical operations involving plutonium and other nuclear materials account for most activities performed at the LANL's Plutonium Facility (PF-4). Here, the presence of large quantities of fissile materials in numerous forms at PF-4 makes it necessary to maintain an active criticality safety program. The LANL Nuclear Criticality Safety (NCS) Program provides guidance to enable efficient operations while ensuring prevention of criticality accidents in the handling, storing, processing and transportation of fissionable material at PF-4. In order to achieve and sustain lower criticality safety control infraction (CSCI) rates, PF-4 operations are continuously improved, through the use of Lean Manufacturing and Six Sigma (LSS) business practices. Employing LSS, statistically significant variations (trends) can be identified in PF-4 CSCI reports. In this study, trends have been identified in the NCS Program using the NCS Database. An output metric has been developed that measures ADPSM Management progress toward meeting its NCS objectives and goals. Using a Pareto Chart, the primary CSCI attributes have been determined in order of those requiring the most management support. Data generated from analysis of CSCI data help identify and reduce number of corresponding attributes. In-field monitoring of CSCI's contribute to an organization's scientific and technological excellence by providing information that can be used to improve criticality safety operation safety. This increases technical knowledge and augments operational safety.

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEA↗
NASA NTRSDate not supplied

Human Systems Integration (HSI) Framework and Training - Shifting the View of HSI for Better Implementation

The Implementation of Human Systems Integration (HSI) presents challenges within the acquisition community for two reasons. The first is that misconceptions of HSI still exist, with many Program Managers (PMs) and leadership uncertain of the value or where to begin. The second is due to an unbalanced approach to HSI in its own framework. These implementation challenges lead to barriers in the early prevention of mishaps. Understanding HSI practices and how they should be implemented in the Acquisition Product Life Cycle (PLC) has been a challenge across the government, leaving the value of HSI unknown and misunderstood with Program Managers. In the case for many acquisition programs, HSI is not implemented in early design, losing the perspective on human capabilities and limitations, creating impacts on human-centered design. Expectations in human performance are not clearly set and operations are baselined with no margin for changes in technology and processes that will affect system performance. The HSI framework addresses total system performance holistically using collaboration as the primary tool. The goal is to create a system with efficiencies while minimizing risk to the operators, maintainers, and support personnel, as well as any collateral personnel and systems. To accomplish this, HSI should be implemented as part of preemptive measures to minimize potential human error and mishaps during the operation phase. Investigative and assessment tools exist that consider events, issues, and other outside influences of a system that may not fall under the current construct of the HSI domains, leaving gaps in early HSI implementation and affecting the prevention of human errors and mishaps. This presentation will outline what NASA HSI is doing to support Early HSI implementation and Operational Performance shifts that affect human performance.

Anthony T Thomas↗
NASA NTRS1991

Flight project data book, 1991

The Office of Space Science and Applications (OSSA) is responsible for planning, directing, executing, and evaluating that part of the overall NASA program that has as its goal the use of the unique characteristics of the space environment to conduct a scientific study of the universe, to solve practical problems on Earth, and to provide the scientific research foundation for expanding human presence beyond Earth into the solar system. OSSA manages the development of NASA's flight instrumentation for space science and applications including free flying spacecraft, Shuttle and Space Station payloads, and the suborbital sounding rockets, balloons, and aircraft programs. A summary is provided of future flight missions, including those approved and currently under development and those which appear in the OSSA strategic plan.

Source record↗
DOE OSTI2016

As Permanent as Practicable: The reality of Permanent Markers - 16191

The regulatory requirements in the United States do not require any specific time frame for the duration of permanent marker systems to inform future generations of the presence of deep geologic nuclear waste repositories. The requirement is for markers to be 'as permanent as practicable'. For the Waste Isolation Pilot Plant in New Mexico, the U.S. Department of Energy chose a 10,000 year Passive Institutional Controls program goal. Passive Institutional Controls are to be designed prior to facility closure and implemented prior to the completion of the Active Institutional Controls program. Nuclear waste repositories across the world are actively developing marker and message systems, as required by their own regulations, for time frames either specified in those regulations or to be proposed to the regulator by the implementing organization. Time frames may be based upon the radioactive characteristics of the various isotopes being disposed of in the repository under consideration, or they may be based on some utility function that balances investment, practicability and risk. Scientifically, there are a number of time frames that make sense. However, an important determinant of effectiveness that has not been taken into consideration is the impact of the human connection, the receiver of the message. The major obstacle that the permanent marker systems need to overcome is the impact that humans will have over time. Historically, no monument has ever survived more than a few thousand years when humans come in contact with it. No matter what size of monument or topic the monument represents, humans have a history of destroying monuments beginning just a few generations after the monument's construction. The only way to ensure that a monument system can endure long time frames is to isolate it from humans. Eliminating contact with humans for whom the messages are meant defeats the very purpose of having an informative marker and message system. A more reasonable and historically supported time frame of 1,000 years would assure that no unreasonable cost would be incurred by current generations. Future generations could decide to continue maintaining the message, or not; and the likelihood of destruction of the markers by subsequent generations would be reduced since the knowledge of the markers and messages would have been transmitted within a more reasonable time frame over which language continuity, for example, would likely be manageable. Future preservation of the marker system and future human actions cannot be controlled, but the goal is to build a marker and message delivery system that reduces the likelihood of inadvertent future human disturbance of a deep geologic repository. This is the typical regulatory requirement on future information systems. Regulators who insist on an extremely long time frame for marker effectiveness should consider the historical realities of 'permanent' markers and monuments and propose a more reasonable time frame. Perhaps it would be more practicable to require 1,000 years for informing future generations and then allow them to determine what they wish to do to protect the future for another, perhaps similar, period of time. (authors)

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

TH-E-209-01: Fluoroscopic Dose Monitoring and Patient Follow-Up Program at Massachusetts General Hospital

Radiation dose monitoring solutions have opened up new opportunities for medical physicists to be more involved in modern clinical radiology practices. In particular, with the help of comprehensive radiation dose data, data-driven protocol management and informed case follow up are now feasible. Significant challenges remain however and the problems faced by medical physicists are highly heterogeneous. Imaging systems from multiple vendors and a wide range of vintages co-exist in the same department and employ data communication protocols that are not fully standardized or implemented making harmonization complex. Many different solutions for radiation dose monitoring have been implemented by imaging facilities over the past few years. Such systems are based on commercial software, home-grown IT solutions, manual PACS data dumping, etc., and diverse pathways can be used to bring the data to impact clinical practice. The speakers will share their experiences with creating or tailoring radiation dose monitoring/management systems and procedures over the past few years, which vary significantly in design and scope. Topics to cover: (1) fluoroscopic dose monitoring and high radiation event handling from a large academic hospital; (2) dose monitoring and protocol optimization in pediatric radiology; and (3) development of a home-grown IT solution and dose data analysis framework. Learning Objectives: Describe the scope and range of radiation dose monitoring and protocol management in a modern radiology practice Review examples of data available from a variety of systems and how it managed and conveyed. Reflect on the role of the physicist in radiation dose awareness.

60 APPLIED LIFE SCIENCES↗
NASA NTRS1977

GEOS-2 refraction program summary document

Data from an extensive array of collocated instrumentation at the Wallops Island test facility were intercompared in order to (1) determine the practical achievable accuracy limitations of various tropospheric and ionospheric correction techniques; (2) examine the theoretical bases and derivation of improved refraction correction techniques; and (3) estimate internal systematic and random error levels of the various tracking stations. The GEOS 2 satellite was used as the target vehicle. Data were obtained regarding the ionospheric and tropospheric propagation errors, the theoretical and data analysis of which was documented in some 30 separate reports over the last 6 years. An overview of project results is presented.

Mallinckrodt, A. J.↗
NASA NTRS1981

Automatic arc welding of propulsion system tubing in close proximity to sensitive electronic devices

The planned final assembly of the Galileo spacecraft propulsion system tubing, which involves welding in close proximity to sensitive electronics, raised significant concerns about the effects of electromagnetic coupling of weld energy on CMOS and other sensitive integrated circuits. A test program was established to assess the potential of an orbital arc welder and an RF-induction brazing machine to damage sensitive electronic equipment. Test parameters were varied to assess the effectiveness of typical transient suppression practices such as grounding, bonding, and shielding. A technique was developed to calibrate the hazard levels at the victim-circuit location; this technique is described along with the results and conclusions of the test program.

Lumsden, J. M.↗