Search NASA⌕ Search

SEARCH · Search NASA

Results for “test protocol”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 811 records · Page 45

Toward a systematic improvement of the fixed-node approximation in diffusion Monte Carlo for solids—A case study in diamond

While Diffusion Monte Carlo (DMC) is in principle an exact stochastic method for ab initio electronic structure calculations, in practice, the fermionic sign problem necessitates the use of the fixed-node approximation and trial wavefunctions with approximate nodes (or zeros). This approximation introduces a variational error in the energy that potentially can be tested and systematically improved. Here, we present a computational method that produces trial wavefunctions with systematically improvable nodes for DMC calculations of periodic solids. These trial wavefunctions are efficiently generated with the configuration interaction using a perturbative selection made iteratively (CIPSI) method. A simple protocol in which both exact and approximate results for finite supercells are used to extrapolate to the thermodynamic limit is introduced. This approach is illustrated in the case of the carbon diamond using Slater–Jastrow trial wavefunctions including up to one million Slater determinants. Fixed-node DMC energies obtained with such large expansions are much improved, and the fixed-node error is found to decrease monotonically and smoothly as a function of the number of determinants in the trial wavefunction, a property opening the way to a better control of this error. The cohesive energy extrapolated to the thermodynamic limit is in close agreement with the estimated experimental value. Interestingly, this is also the case at the single-determinant level, thus, indicating a very good error cancellation in carbon diamond between the bulk and atomic total fixed-node energies when using single-determinant nodes.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Price Based Local Power Distribution Management System (Local Power Distribution Manager) v1.0

A trans-active energy micro-grid controller is implemented in the VOLTTRON distributed control platform. The system uses the price of electricity as the mechanism for conducting transactions that are used to manage energy use and to balance supply and demand. In order to allow testing and analysis of the control system, the implementation is designed to run completely as a software simulation, while allowing the inclusion of selected hardware that physically manages power. Equipment to be integrated with the micro-grid controller must have an IP (Internet Protocol)-based network connection and a software "driver" must exist to translate data communications between the device and the controller.

BROWN, RICHARDE.↗

BOPTest As a Platform for Building Controls and Grid-Interactive Buildings Workforce Training

Building automation and controls are becoming increasingly complex with the emergence of Grid Integrated Efficient Buildings (GEBs) as well as new highly efficient sequences of operation and data-driven control schemes. However, there remains a significant gap in hands-on training opportunities for building operators and technicians to gain practical experience with advanced control systems in a low-risk environment. This paper presents BOPTEST (Building Optimization Performance Test) as a suitable platform for workforce training in building controls and GEB technologies. BOPTEST provides a suite of standardized building simulation test cases with a REST API, real-time control interfaces through BACnet, semantic models connecting users to building data, and built-in calculation of control metrics and performance indicators. The platform enables trainees to interact with virtual buildings using industry-standard protocols while learning how to implement and innovate control strategies. The training platform is designed to offer a structured and interactive learning experience for building engineers, helping them effectively develop, learn, and retain skills in fault identification, troubleshooting, and correction. The workflow is divided into three main phases: 1) Setup, 2) Exercise, and 3) Review, each comprising specific activities performed by either the instructor or the student. Initial pilot training sessions have yielded positive feedback from instructors and participants and demonstrates that BOPTEST effectively fills an industry need for a low-risk training resource via simulation of real building control systems, allowing trainees to gain practical experience before working in the field. The platform's ability to provide immediate performance feedback while maintaining familiar industry interfaces makes it particularly suitable for workforce development programs. This work provides a replicable model for leveraging building simulation in control education and training.

Paul, Lazlo↗

DGaaS: GPU as a Service on Distributed Computing System

In the rapidly evolving landscape of scientific computing, Graphics Processing Units (GPUs) have become indispensable for their unparalleled ability to handle parallel tasks in complex calculations, simulations, and data analysis. Their utility is further magnified in machine learning and AI applications, where they significantly accelerate model training and predictive analytics. Within this context, the Triton Inference Server emerges as a pivotal open-source tool, specializing in AI inferencing and optimizing GPU utilization across various platforms and frameworks. This paper presents an in-depth study on distributed High Throughput Computing (HTC), specifically focusing on the HTCondor framework and its resource provisioning tools, GlideinWMS and HEPCloud. These systems enable large-scale scientific experiments like CMS and DUNE to efficiently access and utilize vast computational resources. The paper explores the core architectural components of GlideinWMS, including jobs, user pools, and worker nodes, and discusses their integration with GPUs and the Triton server. The primary aim of this research is to develop a solution that optimizes GPU utilization by leveraging Glideins and containers. This approach allows computational jobs, particularly those involving AI models, to use GPUs only when essential, thereby facilitating efficient sharing of limited GPU resources. To validate this architecture, the study conducted three key tests involving custom scripts, container-based servers, and Triton server deployments. However, the study faces challenges, notably in locating the Triton server and ensuring secure remote access. To address these issues, future work will focus on developing a proxy mechanism and enhancing security protocols. In conclusion, this study offers a comprehensive roadmap for effective and efficient GPU utilization in distributed High Throughput Computing. It aims to contribute significantly to the scientific community by solving pressing problems and implementing robust solutions in collaboration with the GlideinWMS and HEPCloud teams. The research sets the stage for a more efficient, scalable, and cost-effective paradigm in scientific computing.

97 MATHEMATICS AND COMPUTING↗

BOPTEST as a Platform for Building Controls and Grid-Interactive Buildings Workforce Training

Building automation and controls are becoming increasingly complex with the emergence of Grid Integrated Efficient Buildings (GEBs) as well as new highly efficient sequences of operation and data-driven control schemes. However, there remains a significant gap in hands-on training opportunities for building operators and technicians to gain practical experience with advanced control systems in a low-risk environment. This paper presents BOPTEST (Building Optimization Performance Test) as a suitable platform for workforce training in building controls and GEB technologies. BOPTEST provides a suite of standardized building simulation test cases with a REST API, real-time control interfaces through BACnet, semantic models connecting users to building data, and built-in calculation of control metrics and performance indicators. The platform enables trainees to interact with virtual buildings using industry-standard protocols while learning how to implement and innovate control strategies. The training platform is designed to offer a structured and interactive learning experience for building engineers, helping them effectively develop, learn, and retain skills in fault identification, troubleshooting, and correction. The workflow is divided into three main phases: 1) Setup, 2) Exercise, and 3) Review, each comprising specific activities performed by either the instructor or the student. Initial pilot training sessions have yielded positive feedback from instructors and participants and demonstrates that BOPTEST effectively fills an industry need for a low-risk training resource via simulation of real building control systems, allowing trainees to gain practical experience before working in the field. The platform's ability to provide immediate performance feedback while maintaining familiar industry interfaces makes it particularly suitable for workforce development programs. This work provides a replicable model for leveraging building simulation in control education and training.

Paul, Lazlo↗

Fire and Thermal Experiments in Support of the Model Evaluation Protocol for LNG Facility Fires

The motivation for the experiments reported here pertains to the siting of Liquefied Natural Gas (LNG) facilities which requires assessing the potential adverse radiant thermal impacts of accidental fires on the public. The objective is to obtain data on jet fires, pool fires, fireballs, and concrete walls that could serve as thermal barriers for model validation. The fuels tested include ethane, ethylene, propane, and isopentane.

42 ENGINEERING↗

An international survey of building energy codes and their implementation

Buildings are key to low-carbon development everywhere, and many countries have introduced building energy codes to improve energy efficiency in buildings. Yet, building energy codes can only deliver results when the codes are implemented. For this reason, studies of building energy codes need to consider implementation of building energy codes in a consistent and comprehensive way. This research identifies elements and practices in implementing building energy codes, covering codes in 22 countries that account for 70% of global energy demand from buildings. Access to benefits of building energy codes depends on comprehensive coverage of buildings by type, age, size, and geographic location; an implementation framework that involves a certified agency to inspect construction at critical stages; and independently tested, rated, and labeled building energy materials. Training and supporting tools are another element of successful code implementation, and their role is growing in importance, given the increasing flexibility and complexity of building energy codes. Some countries have also introduced compliance evaluation and compliance checking protocols to improve implementation. This article provides examples of practices that countries have adopted to assist with implementation of building energy codes.

54 ENVIRONMENTAL SCIENCES↗

Face Recognition Oak Ridge (FaRO): A Framework for Distributed and Scalable Biometrics Applications

The facial biometrics community has seen a recent abundance of high-accuracy facial analytic models become freely available. Although these models' capabilities in facial detection, landmark detection, attribute analysis, and recognition are ever-increasing, they aren't always straightforward to deploy in a real-world environment. In reality, the use of the field's ever growing collection of models is becoming exceedingly difficult as library dependencies update and deprecate. Researchers often encounter headaches when attempting to utilize multiple models requiring different or conflicting software packages. Face Recognition Oak Ridge (FaRO) is an open-source project designed to provide a highly modular, flexible framework for unifying facial analytic models through a compartmentalized plug-and-play paradigm built on top of the gRPC (Google Remote Procedure Call) protocol. FaRO's server-client architecture and flexible portability allows easy construction of modularized and heterogeneous face analysis pipelines, distributed over many machines with differing hardware and software resources. This paper outlines FaRO's architecture and current capabilities, along with some experiments in model testing and distributed scaling through FaRO.

Bolme, David↗

N-S3 Cellular Vehicle-to-Everything (C-V2X) Cosimulation Framework [SWR-24-54]

This is a vehicular networking simulator designed to enable synchronized network simulation with vehicle traffic simulation software. The communications model is based on the 3GPP LTE-V2X Mode 4 protocol, but includes several other wireless network protocol models as well. This simulator includes both a V2X network simulation implemented in ns-3 as well as an interface to automatically configure, run, and interact with a set of ns-3 instances based on network size and available hardware. This software has been tested with Aimsun NEXT 2.0 simulator (with V2X SDK), but uses a generic interface for compatibility with any comparable vehicle traffic simulator across the HELICS co-simulation framework. This software is intended as a generalized extension to vehicle traffic simulation, and does not model any vehicle traffic on its own.

Wang, Qichao↗

Wide Area 3D Measurement System for Analysis of 3013 Inner Container Closure Weld Region

One of the main focus areas of the 3013 Surveillance Program is a thorough evaluation of the inner container closure weld region (ICCWR) opened for destructive examination (DE). As part of the protocol to investigate the corrosion in the ICCWR, a laser confocal microscope (LCM) is used to perform close visual examination of the surface and to measure corrosion features on the surface. However, in FY20, the introduction of the Wide Area 3D Measurement System (WAMS) was tested as a method for faster inspection of the ICCWR. Optimization of the WAMS parameters for data collection was carried out using a generic tear-drop type sample containing large and fine Stress Corrosion Cracking (SCC) fractures and high resolution images were compared to the image obtained with the LCM. Although the image with the LCM shows higher resolution than the WAMS images, the small features can be still identified in the WAMS images. The advantage of collecting data for the full circumference using the WAMS is that it can take about a week to complete, which represents 1/16 of the time needed with the LCM. Nonetheless, both systems offer capabilities that combined can be utilized to expedite the examination of the ICCWR. The WAMS can be utilized to obtain images for faster screening or identification of corrosion features on the surface while the LCM can be utilized to obtain higher resolution images of those areas identified by the WAMS.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Restoring Homes After Wildfires, Interviews with Practitioners about Common Cleanup Approaches and Knowledge Gaps

This document summarizes the key themes from our interviews with 10 remediation companies regarding common approaches used to remove odor and contaminants from homes impacted by fire and smoke damage Remediation companies are in agreement that thorough cleaning is the first step. Cleaning and removing contaminants from homes impacted by wildfires may be sufficient to eliminate smoke odor, which is the most important step when it comes to reducing exposure to any residues that may pose health risks to residents. Remediation companies differ in their approaches to addressing odors, such as using ozone generators, hydroxyl generators, chlorine dioxide treatment, thermal fogging and applying sealants. Their opinions of what works and why differs. There is little consensus on efficacy, safety, or application protocols. For example, some view ozone very favorably, while others would prefer using other methods. The influence of insurance companies in their coverage for some methods but not others also impact the decision about the approaches used. Remediation companies differ in their view on laboratory testing for contaminants, which may be partly influenced by insurance companies as well.

99 GENERAL AND MISCELLANEOUS↗

Sensitivity Tests of Aluminum Precipitate Preparation Methods on Head Loss through Debris Beds on a Sump Screen

During a Loss-of-Coolant Accident (LOCA) in Pressurized Water Reactors (PWRs), buffered borated water as a coolant from the Refueling Water Storage Tank (RWST) will be injected into the primary loop to cool down the core depending on the break size. For long-term cooling, the coolant will be collected in the containment sump. Then, the Emergency Core Cooling System (ECCS) will pump the coolant through the sump strainers into the reactor. During this phase, buffered borated water produces chemical precipitate by reacting with the structural materials in the containment. Chemical effects evaluated as part of Generic Safety Issue 191 (GSI-191) resolution studies are broadly defined as any chemically induced phenomenon that affects ECCS performance. Initial chemical effects studies jointly sponsored by the Nuclear Regulatory Commission (NRC) and Industry collaborators led to a Westinghouse Owners Group (WOG) study that provided bases for deterministic quantification of chemical effects. The WCAP-16530-NP developed protocols to produce Aluminum Oxyhydroxide (AlOOH), Calcium Phosphate, and Sodium Aluminum Silicate (SAS). The surrogate generation protocol used the metal salt (aluminum nitrate and calcium acetate) unlike post-LOCA accident scenarios where metals leach into a buffered borated solution. Bahn et al. demonstrated that the WCAP-16530-NP SAS precipitate did not produce as much head loss as the WCAP-16530-NP AlOOH precipitate, thus, the present study focused on the effect of AlOOH precipitate on head loss through a fibrous debris bed. In the past, most of the tests were conducted in high approach velocity conditions, approximately 0.03 m/s. After modifications of sump strainer size in PWRs, the approach velocity to the sump strainer was reduced by an order of magnitude, approximately 0.001 ∼ 0.003 m/s. Howe et al. and Kim et al. conducted several head loss tests at the approach velocity of 0.003 m/s. In the present study, an approach velocity of 0.0006 m/s was selected for an extremely slow power plant condition. A PCI strainer design was used as previous head loss tests and debris bypass tests conducted by Lee et al. Three different chemical precipitate preparation methods were used in this study. The additional head loss of the debris bed caused by those chemical precipitates was investigated. The debris bed was produced with NUKON{sup R} fiberglass thermal insulator and additional particulates including dirt, Tin powder, acrylic powder, and Calcium silicate (CalSil). (authors)

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗

Palliative Prostate Artery Embolization for Prostate Cancer: A Case Series

Introduction: Prostate artery embolization (PAE) is recognized as a treatment for lower urinary tract symptoms (LUTS) in men with benign prostatic hyperplasia. LUTS and urinary retention are common in men with prostate cancer (PCa). The purpose of this study was to estimate the efficacy and safety of palliative PAE on LUTS or urinary retention in men with advanced PCa. Materials and methods: This prospective, single-center trial was conducted from March 2017 to November 2018. The trial protocol was registered online (ClinicalTrials.gov Identifier: NCT03104907). Only men with advanced PCa suffering from LUTS or urinary retention were included. The primary outcome was the ability to void without a catheter and International Prostate Symptom Score (IPSS) in non-catheter-dependent patients. The paired t test was used to analyze changes from baseline with 95% confidence intervals (CI). A p value < 0.05 was considered statistically significant. Results: Seventeen patients were assessed for eligibility, and 15 patients with a mean age of 73.8 years were enrolled. Four men did not complete follow-up: cancer-related death (n = 2), lost to follow-up (n = 1), and unsuccessful embolization due to severe atherosclerosis (n = 1). Bilateral embolization was achieved in ten cases, and urinary retention resolved in one of six patients. LUTS improved in the remaining (n = 5) patients by a mean 12.2-point reduction in IPSS (95% CI − 23.53; − 0.87). According to the CIRSE classification, two grade 1 and two grade 3 complications occurred. Conclusion: In this study, palliative PAE was safe and efficient for treatment for LUTS associated with PCa. Level of Evidence: Level 4, Case Series. Trial registration ClinicalTrials.gov Identifier: NCT03104907.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Prediction of a new ground state of superhard compound B6O at ambient conditions

Boron suboxide B 6 O), the hardest known oxide, has an Rm crystal structure (α-B 6 O) that can be described as an oxygen-stuffed structure of α-boron, or, equivalently, as a cubic close packing of B 12 icosahedra with two oxygen atoms occupying all octahedral voids in it. Here we show a new ground state of this compound at ambient conditions, Cmcm-B 6 O) (β-B 6 O)), which in all quantum-mechanical treatments that we tested comes out to be slightly but consistently more stable. Increasing pressure and temperature further stabilizes it with respect to the known α-B 6 O) structure. β-B 6 O) also has a slightly higher hardness and may be synthesized using different experimental protocols. We suggest that β-B 6 O) is present in mixture with α-B 6 O), and its presence accounts for previously unexplained bands in the experimental Raman spectrum.

Science & Technology - Other Topics↗

Challenges in Continuous In-Field Critical Current Testing of High-Temperature Superconducting Tapes: Thermal and Mechanical Perspectives

High-temperature superconductors (HTS) are essential for ultra-high-field applications requiring exceptional current-carrying capacity under extreme conditions. However, systematic characterization of critical current in long-length conductors remains challenging due to complex thermal, electromag netic, and mechanical interactions during continuous testing. This study reports the development of a continuous in-field magnetization testing system for position-dependent critical current measurement in HTS tapes at 20 K under 7.5 T fields applied normal to the tape plane, enabling identification of performance-limiting regions that could compromise magnet stability. Here, the system addresses two fundamental challenges inherent to cryogenic reel to-reel testing. First, thermal management requires continuous cooling of a moving conductor to 20 K, achieved through liquid nitrogen precooling combined with a 100 W@20 K Gifford McMahon cryocooler. Second, screening currents in high fields generate Lorentz forces that induce twisting, bowing, and potential delamination. To mitigate these risks, we propose mechanical reinforcement and active current density suppression strategies. Numerical simulations using the stream function formulation reveal four primary failure modes: frictional heating at guide interfaces, unstable equilibria causing deformation, transverse current-induced stresses at guide transitions, and unsupported forces in vertical spans. Our mitigation strategies include PTFE coated guides to minimize friction, spring-loaded stabilization mechanisms to maintain tape alignment, controlled pre-heating using the liquid nitrogen thermal jacket to suppress critical current at stress points, and optimized guide positioning to minimize force accumulation. The experimental system is nearing completion, with testing planned to commence within two months. Preliminary validation at 65 K under 0.5 T demonstrates strong correlation between simulation-predicted mechanical instabilities and observed critical current variations during conductor tran sitions through the measurement region. These findings establish a robust foundation for quality assurance protocols essential to next-generation superconducting magnet applications.

Chen, Siwei [Princeton Plasma Physics Laboratory (↗

SU-C-207-02: A Method to Estimate the Average Planar Dose From a C-Arm CBCT Acquisition

Purpose: The planar average dose in a C-arm Cone Beam CT (CBCT) acquisition had been estimated in the past by averaging the four peripheral dose measurements in a CTDI phantom and then using the standard 2/3rds peripheral and 1/3 central CTDIw method (hereafter referred to as Dw). The accuracy of this assumption has not been investigated and the purpose of this work is to test the presumed relationship. Methods: Dose measurements were made in the central plane of two consecutively placed 16cm CTDI phantoms using a 0.6cc ionization chamber at each of the 4 peripheral dose bores and in the central dose bore for a C-arm CBCT protocol. The same setup was scanned with a circular cut-out of radiosensitive gafchromic film positioned between the two phantoms to capture the planar dose distribution. Calibration curves for color pixel value after scanning were generated from film strips irradiated at different known dose levels. The planar average dose for red and green pixel values was calculated by summing the dose values in the irradiated circular film cut out. Dw was calculated using the ionization chamber measurements and film dose values at the location of each of the dose bores. Results: The planar average dose using both the red and green pixel color calibration curves were within 10% agreement of the planar average dose estimated using the Dw method of film dose values at the bore locations. Additionally, an average of the planar average doses calculated using the red and green calibration curves differed from the ionization chamber Dw estimate by only 5%. Conclusion: The method of calculating the planar average dose at the central plane of a C-arm CBCT non-360 rotation by calculating Dw from peripheral and central dose bore measurements is a reasonable approach to estimating the planar average dose. Research Grant, Siemens AG.

60 APPLIED LIFE SCIENCES↗

Abstract for CRADA between the Japan Oil, Gas, and Metals National Corporation (JOGMEC) and NETL (AGMT-0671)

The US Department of Energy’s National Energy Technology Laboratory (NETL) and the Japan Oil, Gas, and Metals National Corporation (JOGMEC) have long-established gas hydrate R&D programs and both have identified an extended duration scientific field test of depressurization as a key requirement in advancing critical science and technology development objectives. Both Parties recognize that the Alaska North Slope (“ANS”) is the most feasible location on Earth to conduct such a test and that a proven ANS Operator should be engaged to carry out the desired scientific drilling and testing field programs in full compliance with all regulations. Given the unpredictable nature of field programs conducted in harsh operating environments, the parties have executed this CRADA to clearly establish a basic framework of the project goals, and to articulate roles, responsibilities, and decision-making protocols prior to the initiation of a field program. Therefore, this CRADA establishes a project “Steering Committee” to guide major project decision points and allocation of resources; an “R&D Committee” to jointly develop field program technical and scientific plans designed to achieve program objectives; and “Field Representatives” to enable effective, real-time, and collaborative decision making during field programs.

03 NATURAL GAS↗