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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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DOE OSTI2022

Position Papers for the ASCR Workshop on the Management and Storage of Scientific Data

The purpose of this workshop is to identify priority research directions in the area of data management for high-performance and scientific computing above and beyond HPC’s traditional "the parallel file system is the data-management system" model. Supporting the breadth of the DOE mission, including the explosion of AI uses and the growing needs of experimental and observational science, motivates revisiting our assumptions about data management. There are many facets of this topic to explore including: (1) Interfaces for accessing data that resides on traditional persistent storage as well as memory devices; (2) Storage-system architecture design that supports scientific workflows on varied hierarchical storage and networking devices; (3) Devising metadata management infrastructure to support FAIR principles (Findability, Accessibility, Interoperability, and Reusability); (4) Capturing provenance information about scientific data; (5) Utilizing AI to learn I/O patterns of emerging workloads for efficient data management; (6) Providing data management support for AI and complex workflows; and (7) Understanding the overlap between traditional storage systems and I/O (SSIO) efforts and data management. While the program committee has identified these topics as important areas for discussion, we welcome position papers from the community that propose additional topics of interest for discussion at the workshop. The workshop agenda will include breakout sessions for discussing these and selected topic areas to inform priority research directions for data management for high-performance and scientific computing.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2021

Microstructural-Level Fuel Performance Modeling of U-Mo Monolithic Fuel

As the physics that governs the microstructural evolution of nuclear fuel span various time and spatial scales, to fully understand the fuel behavior inevitably involves atomic to mesoscale resolution that can be difficult to determine experimentally. Microstructural-level modeling and simulations can be used to develop physics-based materials models that can provide physical understanding to inform fabrication process control, as well as a valuable feedback mechanism between post-irradiation examination (PIE) results and fabrication parameters. In accordance with the program schedule, the primary goals of the microstructure modeling effort are to: 1. Address critical microstructural questions and provide practical guidance to the fabricator via the fuel product specification; 2. Provide mechanistic inputs for the existing fuel performance code to improve its descriptive and predictive capability at the macroscopic scale. In fiscal year (FY)-21, the work scope consisted of six main facets: (1) the effect of carbides on fuel performance; (2) gas diffusivity in different phases; (3) integration of microstructural fuel performance modeling; (4) property degradation; (5) irradiation creep; and (6) historical analysis of microstructure data. Brief summaries of each are included below.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2021

Research software engineering: Professionalization, roles, and identity

This report summarizes the results of a study of research software professionals based on 17 interviews conducted at U.S. national laboratories and academic institutions. The study focuses on understanding the emerging professional role of research software engineer (RSE) and examining how the history of software engineering might be relevant to the emergence of research software engineering as a professional movement. The report first uses interview data to identify several models of professional identity for research software professionals. These include dominance models in which a person strongly identifies with a single professional identity (such as RSE), and multiplicity models in which an individual sees an identity like RSE as just one facet of their overall professional role. Next, it identifies three types of work situations for software professionals at national laboratories, covering those who work in dedicated RSE organizations, those who play an integral role in large multiphysics code projects, and those who work in a more isolated capacity to provide software development support for less computationally intensive research projects. It then reviews some key ideas from the sociology of professions in the context of the software engineering profession, suggesting parallels between the current RSE professional movement and aspects of the history of software engineering. It concludes by suggesting some potential practical implications of these findings for the RSE movement and professional organizations.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2022

Report for the ASCR Workshop on the Management and Storage of Scientific Data

The purpose of this workshop is to identify priority research directions in the area of data management for high-performance and scientific computing above and beyond HPC’s traditional "the parallel file system is the data-management system" model. Supporting the breadth of the DOE mission, including the explosion of AI uses and the growing needs of experimental and observational science, motivates revisiting our assumptions about data management. There are many facets of this topic to explore including: (1) Interfaces for accessing data that resides on traditional persistent storage as well as memory devices; (2) Storage-system architecture design that supports scientific workflows on varied hierarchical storage and networking devices; (3) Devising metadata management infrastructure to support FAIR principles (Findability, Accessibility, Interoperability, and Reusability); (4) Capturing provenance information about scientific data; (5) Utilizing AI to learn I/O patterns of emerging workloads for efficient data management; (6) Providing data management support for AI and complex workflows; and (7) Understanding the overlap between traditional storage systems and I/O (SSIO) efforts and data management. While the program committee has identified these topics as important areas for discussion, we welcome position papers from the community that propose additional topics of interest for discussion at the workshop. The workshop agenda will include breakout sessions for discussing these and selected topic areas to inform priority research directions for data management for high-performance and scientific computing.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2022

NSRC New Hire Orientation: Resources and What to Expect

Hello, New Hire! Right now, you are likely very excited to begin your position at the Laboratory. We are happy you are here! This document will walk you through different facets of your pre-security clearance interval at the Lab. This is a general guide not firm documentation. Its contents were compiled by National Security Research Center (NSRC) team members to make your transition easier. To begin, you will need a security clearance to do your job. A security clearance is essentially an extremely detailed background check. After you complete and turn in your security paperwork, the clearance process can take as little as three months or as long as one year. You may wonder, “If I can’t do my job until after I receive a clearance, what will I be doing?” There is plenty of unclassified work and professional development to be done. Waiting for a clearance can be trying, but we are here to help. This guide details what to expect during pre-clearance, resources to stay industrious, entry points to Lab networking and culture, and tips for success. Patience, flexibility, and productivity are key. Your workday responsibilities and priorities will vary depending on the self-study, assigned duties, and client-driven projects designated by your manager. This guide is here to help, and so are your NSRC colleagues.

96 KNOWLEDGE MANAGEMENT AND PRESERVATION↗
DOE OSTI2022

A Mountaintop View Requires Minimal Sorting: A Faster Contour Tree Algorithm

Consider a scalar field f : M → R, where M is a triangulated simplicial mesh in R d . A level set, or contour, at value v is a connected component of f –1 (v). As v is changed, these contours change topology, merge into each other, or split. Contour trees are concise representations of f that track this contour behavior. The vertices of these trees are the critical points of f, where the gradient is zero. The edges represent changes in the topology of contours. It is a fundamental data structure in data analysis and visualization, and there is significant previous work (both theoretical and practical) on algorithms for constructing contour trees. Suppose M has n vertices, N facets, and t critical points. A classic result of Carr, Snoeyink, and Axen (2000) gives an algorithm that takes O(n log n+Nα(N)) time (where α(·) is the inverse Ackermann function). A further improvement to O(t log t + N) time was given by Chiang et al. All these algorithms involve a global sort of the critical points, a significant computational bottleneck. Unfortunately, lower bounds of Ω(t log t) also exist. We present the first algorithm that can avoid the global sort and has a refined time complexity that depends on the contour tree structure. Intuitively, if the tree is short and fat, we get significant improvements in running time. For a partition of the contour tree into a set of descending paths, P, our algorithm runs in O($\Sigma$ pϵP |p| log |p| + tα(t) + N). This is at most O(t log D + N), where D is the diameter of the contour tree. Moreover, it is O(tα(t) + N) for balanced trees, a significant improvement over the previous complexity. Our algorithm requires numerous ideas: partitioning the contour tree into join and split trees, a local growing procedure to iteratively build contour trees, and the use of heavy path decompositions for the time complexity analysis. There is a crucial use of a family of binomial heaps to maintain priorities, ensuring that any comparison made is between comparable nodes of the contour tree. We also prove lower bounds showing that the $\Sigma$ pϵP |p| log |p| complexity is inherent to computing contour trees.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2022

Alabama Industrial Assessment Center: Training Students and Sustaining Industry (Final Report)

The overarching goal of this project is to educate and train engineering students in energy management protocols. The centerpiece of the program is achieved by delivering direct energy-management assistance to manufacturers through industrial assessments and workshops. Additional facets are achieved through report writing, formal curricular coursework, and on-line/self-directed training. This program delivered significant workforce development in the area of energy management practices. Participants in the program received hands-on experience in real-world industrial energy usage and management practices. Additionally, the industrial manufacturers received benefit of collective energy management skills of the research team towards reducing energy consumption at their sites. These activities are beneficial to the public in two ways. First, the trained participants from the program will move out into the manufacturing sector and propagate the energy management expertise they gathered during the program. This is a long-term benefit that will pay back to society over many years. Second, the manufacturers that receive energy assistance under the program realize a direct and immediate increase in their energy efficiency.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2022

FY2022 Q4: Demonstrate multi-turbine simulation with hybrid-structured/unstructured-moving-grid software stack running primarily on GPUs and propose improvements for successful KPP-2 [Poster]

Milestone accomplishments staged the ExaWind team for successful completion of KPP-2 challenge problem in FY23, which requires the simulation on Frontier of at least four MW-scale turbines in an atmospheric boundary layer with at least 20B gridpoints. The ExaWind project and software stack is many faceted, with team members working on multiple areas, including linear-system solvers (Trilinos, hypre, AMReX), overset meshes, turbulence modeling, and in situ visualization, all with an aim for high fidelity predictions and performance portability. This milestone marks significant improvements on many fronts and provides the team with a pathway to exascale wind farm simulations in FY23.

17 WIND ENERGY↗
DOE OSTI2022

Carrier Dynamics of Polar, Semipolar, and Nonpolar InGaN/GaN LEDs Measured by Small-Signal Electroluminescence

The carrier dynamics in InGaN/GaN light-emitting diodes (LEDs) are directly tied to their efficiency and maximum modulation speed, which are important metrics for solid-state lighting, displays, and optical communication. In this work, we measure the carrier dynamics of a variety of InGaN/GaN LEDs using small-signal electroluminescence methods [1]. A rate equation approach and associated small-signal circuit are used to model carrier injection, recombination in the active region, recombination in the cladding regions, and carrier escape. The model is fit to the measured optical frequency response (S21) and input impedance (S11) of the LEDs to extract the various carrier lifetimes, the carrier density, and the radiative and non-radiative recombination rates. We specifically study planar nonpolar and semipolar LEDs, which show record-high modulation speeds for III-nitride LEDs and present the modulation characteristics of core-shell nanowire-based LEDs. The planar nonpolar m-plane ($101\bar{0}$) micro-LEDs achieve a record-high -3dB modulation bandwidth for a III-nitride LED of 1.5 GHz [2]. The -3dB response of an electrically injected nanowire-based micro-LED with nonpolar facets is also reported, showing a -3dB bandwidth of 1.2 GHz [3]. The high speed is attributed to the shorter carrier lifetime associated with the nonpolar orientation. We also study the carrier dynamics in semipolar ($20\bar{2}\bar{1}$) LEDs for various temperatures [4]. Finally, we present carrier dynamics measurements on commercial-grade c-plane epitaxy for various active region designs, including a wavelength series and a growth quality series. The wavelength series offers insight into the contributions of the quantum confined Stark effect (QCSE) and InGaN material quality on the green gap [5]. The growth quality series investigates the role of non-radiative centers on the LED performance. Extraction of the carrier dynamics using small-signal electroluminescence offers insight into the factors limiting the efficiency and high-speed performance of III-nitride emitters and can be leveraged to ultimately improve the devices.

LEDs, InGaN, electroluminescence, bandwidth, modul↗
DOE OSTI2022

How We Do Our Work Is as Important as What We Do: A History of Los Alamos National Laboratory Operations

Los Alamos National Laboratory is known for its world-renowned research and Nobel Prize–winning scientists. Few know about the support required to keep the Laboratory running. This book takes you behind the scenes for a closer look at Laboratory operations and the individuals, programs, and facilities of yesteryear and today. From infrastructure, security, staffing, and many other facets, Laboratory operations is what makes the science happen.

96 KNOWLEDGE MANAGEMENT AND PRESERVATION↗
DOE OSTI2022

Domestic MC&A Recommendations for Liquid-Fueled MSRs

Investments by the US Department of Energy (DOE) are providing opportunities for vendors and developers of advanced reactor technologies to move toward experimental reactor systems, leading to commercial scale facilities. One facet of complementary research under the Advanced Reactor Safeguards program in the DOE Office of Nuclear Energy (NE-5) is motivated to assist vendors in licensing under the existing US (domestic) regulatory body’s federal regulations. This report provides concepts, approaches, and recommendations for liquid-fueled molten salt reactor (MSR) vendors to meet the material control and accountability (MC&A) and licensing requirements set forth by the US Nuclear Regulatory Commission (NRC) to possess and handle special nuclear material.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
DOE OSTI2022

Transportation Plan Los Alamos National Laboratory FY2023

Los Alamos National Laboratory’s (LANL’s) mission expansion is expected to increase the workforce population (badge holders) to more than 18,000 by 2028. Before the COVID-19 pandemic, traffic congestion was notable and was impeding commuting workers in the forms of traffic congestion, travel delay, inconvenience, frustration, and time lost hunting for parking near an office location or programmatic operation. The Laboratory transportation strategy is moving toward transit-based commuting and not status quo expansion of onsite parking and roadways to serve this growing workforce. This plan addresses a multi-faceted transit and transportation solution. The body of the plan describes each aspect of this solution and concludes with a recommended set of Fiscal Year 2023 (FY23) investments planned as next steps toward implementation. The broad strategy is to offer agility and program depth for services and systems that can enable LANL to confidently invest, monitor performance, seek participant feedback, and make necessary adjustments.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2020

302.2.03 Report on P43OL1139

This document describes the quality issues encountered in bare cable P43OL1139AA00A fabrication and the subsequent investigation performed at LBNL. The cable concerned was placed under L3 quarantine (braiding held, further QC required) in December 2020 upon fabrication due to mid-run facet size increase, and was elevated to L2 quarantine in February 2020 to require a more formal reporting and resolution. The approval (rejection) of this report by L2 on DocDB shall constitute acceptance (rejection) of the fabrication of the bare cable unit P43OL1139AA00A, upon which it may (may not) proceed to braiding and EVMS HO.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Quality Ranking System for Molten Salt Thermal Property Data

A simple ranking system for use with data and property values compiled in the Molten Salt Thermal Database-Thermophysical Properties (MSTDB-TP) is presented. The approach includes assessments of five features of data collection: the method used to measure the property value, calibration of devices used to make the measurements, the quantified uncertainty of the results, control of the environmental conditions, and determination of the salt composition. The verifiability of how the property value was determined is also assessed based on information provided or cited within the data set. The quality of each facet is ranked as High, Moderate, or Incomplete based on objective metrics. The overall quality of the dataset is ranked based on rankings of the five data features and the reported property value, with rankings of A and B indicating the data and property value are deemed suitable for quantitative use and U indicating uncertainties that restrict the recommended use to qualitative purposes. The system is suitable for assessing data already in the MSTDB-TP and screening new entries.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2021

Self-Healing Ceramics and Mechanical Metamaterials

We performed large scale molecular dynamics (MD) simulations and reactive & quantum molecular dynamics simulations to investigate: (1) faceting, grain growth, and crack healing in ceramics; (2) stress-release mechanism and healing in fibers; and (3) mechanical properties of two-dimensional metamaterials. We also designed highly accurate interatomic potentials and forces using artificial neural networks (ANN) and first-principles molecular dynamics simulation data for use in our MD and reactive MD simulations. We demonstrated the efficacy of modeling quantum materials atomistic simulation data using unsupervised deep learning approaches on a quantum computer. These achievements are elaborated in the following sections.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Cultural Resource Management Plan for Brookhaven National Laboratory

The Cultural Resource Management Plan (CRMP) for Brookhaven National Laboratory (BNL) provides an organized guide that describes or references the facets and interrelationships of cultural resources at BNL. Management strategies included within this CRMP are designed to adequately identify the cultural resources that BNL and DOE consider significant and to acknowledge associated management actions. A principal objective of the CRMP is to reduce the need for additional regulatory documents and to serve as the basis for a formal agreement between the DOE and the New York State Historic Preservation Officer (NYSHPO). The BNL CRMP is designed to be a “living document.” Each section includes identified gaps in the management plan, with proposed goals and actions for addressing each gap. The plan will be periodically revised to incorporate new documentation. The current (2023) update incorporates new findings and/or updated text based on completed or ongoing projects related to cultural resources at BNL since inception of the last updated CRMP in 2013. Historically, Brookhaven National Laboratory had little need for cultural resource management because many of its buildings were less than 50 years old. Most of the features that are potentially eligible for inclusion in the National Register of Historic Places were protected simply by avoiding the features. Compliance with cultural resource laws and regulations has included archeological surveys, such as those associated with the 1977 Final Environmental Impact Statement for Brookhaven National Laboratory and the 1978 Final Environmental Impact Statement for the Proton-Proton Storage Accelerator Facility (ISABELLE). In 1979, World War I trenches associated with the former Camp Upton and located near ISABELLE were determined to be eligible for inclusion in the National Register of Historic Places; however, many of these trenches had been destroyed by construction work. In 1991, the NYSHPO provided BNL with a letter indicating that only three structures and features were likely to be eligible for inclusion in the National Register of Historic Places. Between 1991 and 1999, little work associated with cultural resource management was accomplished. Beginning in 1999, awareness for the need of a program to manage cultural resources grew out of the realization that over half of the buildings at BNL were either 50 years old or were reaching that age and were, therefore, subject to the requirements in Section 106 of the National Historic Preservation Act. This fact, concomitant with the decontamination and decommissioning of the Brookhaven Graphite Research Reactor (BGRR) and the subsequent determination of BGRR’s eligibility for listing as an historical site, fueled the need for developing and implementing a more structured program for managing cultural resources at BNL.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2023

Transmission Optimization with Grid Enhancing Technologies Fact Sheet

The Transmission Optimization with Grid Enhancing Technologies (TOGETs) project is funded by the Department of Energy (DOE) Office of Electricity (OE) and Wind Energy Technologies Office (WETO). Idaho National Laboratory’s TOGET Task force consists of regulatory, utility, system operator, vendor, academic, and other industry participants, who will guide a two-pronged approach to fill in gaps on publicly available knowledge of GETs and conduct a full scale, multi-faceted field exercise. Ultimately the project aims to test, verify, and validate deployed GETs in a transmission system.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2023

TOGETs Overview

The Transmission Optimization with Grid Enhancing Technologies (TOGETs) project will guide future research to fill in gaps on publicly available knowledge of Grid Enhancing Technologies (GETs) and conduct a full scale, multi-faceted field exercise. Ultimately the project aims to test, verify and validate deployed GETs in a transmission system.

24 POWER TRANSMISSION AND DISTRIBUTION↗