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Results for “SAFETY DEVICE”

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 199 records · Page 11
All sourcesNASA NTRSDOE OSTI
DOE OSTI2015

Characterization and implementation of OSL dosimeters for use in evaluating the efficacy of organ-based tube current modulation for CT scans of the face and orbits

Purpose: The purpose of this work was to characterize commercially available optically stimulated luminescent (OSL) dosimeters for general clinical applications and apply the results to the development of a method to evaluate the efficacy of a vendor-specific organ-based tube current modulation application for both phantom and clinical computed tomography (CT) scans of the face and orbits. Methods: This study consisted of three components: (1) thorough characterization of the dosimeters for CT scans in phantom, including evaluations of depletion, fading, angular dependence, and conversion from counts to absorbed dose; (2) evaluation of the efficacy of using plastic glasses to position the dosimeters over the eyes in both phantom and clinical studies; and (3) preliminary dosimetry measurements made using organ-based tube current modulation in computed tomography dose index (CTDI) and anthropomorphic phantom studies. Results: (1) Depletion effects were found to have a linear relationship with the output of the OSL dosimeters (R{sup 2} = 0.96). Fading was found to affect dosimeter readings during the first two hours following exposure but had no effect during the remaining 60-h period observed. No significant angular dependence was observed for the exposure conditions used in this study (with p-values ranging from 0.9 to 0.26 for all t-tests). Dosimeter counts varied linearly with absorbed dose when measured in the center and 12 o’clock positions of the CTDI phantoms. These linear models of counts versus absorbed dose had overlapping 95% confidence intervals for the intercepts but not for the slopes. (2) When dosimeters were positioned using safety glasses, there was no adverse effect on image quality, and there was no statistically significant difference between this placement and placement of the dosimeters directly on the eyes of the phantom (p = 0.24). (3) When using organ-based tube current modulation, the dose to the lens of the eye was reduced between 19% and 43%, depending on the scan protocol used and the positioning of the phantom. Furthermore, the amount of dose reduction was significantly affected by the vertical position of the phantom, with the largest reduction in dose seen when the phantom was centered in the gantry. Conclusions: (1) An appropriate correction factor, specific to CT scanning, was developed to account for depletion and fading characteristics of the dosimeters. Additionally, an equation to convert dosimeter counts to absorbed dose was established. (2) The use of plastic safety glasses was validated as an appropriate positioning device when measuring dose to the lens of the eye. (3) The use of organ-based tube current modulation can reduce dose to the lens of the eye during CT scanning. The amount of dose reduction, however, is largely influenced by the positioning of the anatomy in the gantry.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2019

Heat and Particle Transport in the Initial Phase of Ohmic Discharges in the Globus-M Spherical Tokamak

The results of experiments and simulations of the transport of heat and particles in the Globus-M spherical tokamak are presented. Investigations were carried out in the ohmic mode in hydrogen and deuterium plasma. It is shown that in the phase of current growth under the same initial conditions, as long as the condition is met at which the minimum of the safety factor exceeds unity, two scenarios of discharge development are possible: with an electron temperature dive or with an electron density peak. After the safety factor reaches the value of 1, the differences are no longer observed. Modeling of transport processes using the ASTRA code showed that the dive of the electron temperature and density is a consequence of the decrease in the transport of heat and particles in the plasma core (i.e., the presence of internal transport barriers).

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2024

Advances in solid-state batteries: Materials, interfaces, characterizations, and devices

Solid-state batteries with features of high potential for high energy density and improved safety have gained considerable attention and witnessed fast growing interests in the past decade. Significant progress and numerous efforts have been made on materials discovery, interface characterizations, and device fabrication. Further, this issue of MRS Bulletin focuses on the current state of the art of solid-state batteries with the most important topics related to the interface issues, advanced characterizations, and electrode chemistries, aiming to provide a comprehensive perspective for the interface and characterization challenges for high-performance solid-state battery devices.

25 ENERGY STORAGE↗
DOE OSTI2012

Mitsubishi experience on digital I and C and modernization

Digital systems are being applied to instrumentation and control (I and C) systems, including safety and non-safety systems, to accommodate obsolescence of existing analog devices or to obtain the benefits of digital I and C systems in new nuclear power plants as well as existing plants. This paper presents the Mitsubishi experience of digital I and C application and modernization. (authors)

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2011

Performance and Economic Analysis of Distributed Power Electronics in Photovoltaic Systems

Distributed electronics like micro-inverters and DC-DC converters can help recover mismatch and shading losses in photovoltaic (PV) systems. Under partially shaded conditions, the use of distributed electronics can recover between 15-40% of annual performance loss or more, depending on the system configuration and type of device used. Additional value-added features may also increase the benefitof using per-panel distributed electronics, including increased safety, reduced system design constraints and added monitoring and diagnostics. The economics of these devices will also become more favorable as production volume increases, and integration within the solar panel?s junction box reduces part count and installation time. Some potential liabilities of per-panel devices includeincreased PV system cost, additional points of failure, and an insertion loss that may or may not offset performance gains under particular mismatch conditions.

14 SOLAR ENERGY↗
DOE OSTI2016

Technical Basis for Electromagnetic Compatibility Regulatory Guidance Update

The objective of this report is to serve as the technical basis document for the next, planned revision of this RG that highlights and provides the rationale for the recommended changes. The structure of this document follows and summarizes the several assessment activities undertaken during the course of this project to evaluate new and updated electromagnetic compatibility (EMC) standards, testing methods and limits, and relevant technology developments being incorporated into plant activities that may have EMI/RFI implications, as well as other specific issues, including impacts of electrostatic discharge (ESD) on safety equipment and impacts on increased usage of wireless devices in nuclear power plants.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
DOE OSTI2012

Laboratories for the 21st Century Best Practices: Energy Recovery in Laboratory Facilities

Laboratories typically require 100% outside air for ventilation at higher rates than other commercial buildings. Minimum ventilation is typically provided at air change per hour (ACH) rates in accordance with codes and adopted design standards including Occupational Safety and Health Administration (OSHA) Standard 1910.1450 (4 to 12 ACH – non-mandatory) or the 2011 American Society of Heating, Refrigerating and Air Conditioning Engineers (ASHRAE) Applications Handbook, Chapter 16 – Laboratories (6 to 12 ACH). While OSHA states this minimum ventilation rate “should not be relied on for protection from toxic substances released into the laboratory” it specifically indicates that it is intended to “provide a source of air for breathing and for input to local ventilation devices (e.g., chemical fume hoods or exhausted bio-safety cabinets), to ensure that laboratory air is continually replaced preventing the increase of air concentrations of toxic substances during the working day, direct air flow into the laboratory from non-laboratory areas and out to the exterior of the building.” The heating and cooling energy needed to condition and move this outside air can be 5 to 10 times greater than the amount of energy used in most office buildings. In addition, when the required ventilation rate exceeds the airflow needed to meet the cooling load in low-load laboratories, additional heating energy may be expended to reheat dehumidified supply air from the supply air condition to prevent over cooling. In addition to these low-load laboratories, reheat may also be required in adjacent spaces such as corridors that pro-vide makeup air to replace air being pulled into negative-pressure laboratories.

Laboratories, Best Practices, Energy, Facilities↗
DOE OSTI2010

Unproven screening devices threaten the lives of police and military.

In a world plagued with improvised explosive devices, drugs and dangerous people, the desire to field technology to protect our police and military is providing a fertile market for the proliferation of protection technologies that range from the unproven to the disproven. The market place is currently being flooded with detection equipment making inflated and inaccurate marketing claims of high reliably, high detection probabilities, and ease of operation - all while offering detection capabilities at safe distances. The manufacturers of these devices have found a willing global marketplace, which includes some of the most dangerous places in the world. Despite a wealth of contradictory performance and testing data available on the Internet, sales of these devices remain brisk and profitable. Rather than enhancing the security of police and military personnel, the reliance on these unproven and disproven devices is creating a sense of false security that is actually lowering the safety of front-line forces in places like Iraq and Afghanistan. This paper addresses the development and distribution history of some of these devices and describes the testing performed by Sandia National Laboratories in Albuquerque, and other reputable testing agencies that illustrate the real danger in using this kind of unproven technology.

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗
DOE OSTI2014

Tritium Breeding Blanket for a Commercial Fusion Power Plant - A System Engineering Assessment

The goal of developing a new source of electric power based on fusion has been pursued for decades. If successful, future fusion power plants will help meet growing world-wide demand for electric power. A key feature and selling point for fusion is that its fuel supply is widely distributed globally and virtually inexhaustible. Current world-wide research on fusion energy is focused on the deuterium-tritium (DT for short) fusion reaction since it will be the easiest to achieve in terms of the conditions (e.g., temperature, density and confinement time of the DT fuel) required to produce net energy. Over the past decades countless studies have examined various concepts for TBBs for both magnetic fusion energy (MFE) and inertial fusion energy (IFE). At this time, the key organizations involved are government sponsored research organizations world-wide. The near-term focus of the MFE community is on the development of TBB mock-ups to be tested on the ITER tokamak currently under construction in Caderache France. TBB concepts for IFE tend to be different from MFE primarily due to significantly different operating conditions and constraints. This report focuses on longer-term commercial power plants where the key stakeholders include: electric utilities, plant owner and operator, manufacturer, regulators, utility customers, and in-plant subsystems including the heat transfer and conversion systems, fuel processing system, plant safety systems, and the monitoring control systems.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2021

Impact of cyberattacks on safety and stability of connected and automated vehicle platoons under lane changes

Connected and automated vehicles (CAVs) offer a huge potential to improve the operations and safety of transportation systems. However, the use of smart devices and communications in CAVs introduce new risks. CAVs would leverage vehicle to vehicle (V2V) and vehicle to infrastructure (V2I) communication, thus providing additional system access points compared to traditional systems. Automation makes these systems more vulnerable and increases the consequences of cyberattacks. This study utilizes an infrastructure-based communication platform consisting of cooperative adaptive cruise control and lane control advisories developed by the authors to perform cyber risk assessment of CAVs. The study emulates three types of cyberattacks (message falsification, dedicated denial of service, and spoofing attacks) in a representative traffic environment consisting of multiple CAV platoons and lane change events to analyze the safety and stability impacts of the cyberattacks. Simulation experiments using VISSIM reveals that traffic stream and CAV string is unstable under all three types of cyberattacks. The worst case is represented by the message falsification attack. Increases in volatility are observed over a no attack case, with variations increasing by an average of 43%–51% along with an increase of over 3000 crash conflicts. Similarly, lane change crash conflicts are observed to be more severe compared to rear end crash conflicts, showing a higher probability of severe injuries. Further, the case of slight cyberattack on a single CAV also creates significant disruption in the traffic stream. Analysis of variance (ANOVA) reveals the statistical significance of the results. Furthermore, these results pave the way for future design of secure systems from a monitoring perspective.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2025

A Novel, Low-Cost, Portable Device for Counterfeit and Noncompliant Refrigerant Detection

The increasing prevalence of counterfeit refrigerants presents significant risks to Heating, Ventilation, Air Conditioning, and Refrigeration (HVACR) systems, including compromised equipment performance, safety hazards, and environmental non-compliance. This report details the development of a novel, cost-effective, and portable detection device designed to accurately identify counterfeit refrigerants. The device utilizes a controlled gas sampling and analysis system within a sealed chamber, ensuring precise measurements while maintaining safety through a purging mechanism. The system features a high-sensitivity sensor integrated with an onboard control module that analyzes gas composition in real-time, providing users with clear visual indicators for refrigerant authenticity.Laboratory validation demonstrated the device’s high accuracy (exceeding 95%) in detecting unauthorized refrigerant blends. Key advantages include affordability, ease of use, rapid response time, and compatibility with a wide range of refrigerants. This solution supports compliance with regulatory frameworks such as the American Innovation and Manufacturing (AIM) Act, enhances safety in HVACR operations, and mitigates the risks associated with counterfeit refrigerants. Future developments will focus on expanding refrigerant detection capabilities, integrating machine learning for enhanced accuracy, implementing cost-reduction strategies to improve accessibility and market adoption, and optimizing system packaging for enhanced field portability.

99 GENERAL AND MISCELLANEOUS↗
DOE OSTI2023

A Blockchain-Enabled Sustainable Safety Management Framework for Connected Vehicles

The notion of an intelligent transportation system (ITS) aims to boost the performance of transportation networks, which has gained more and more traction in both academic and commercial circles. ITS is a constantly evolving vision that combines cutting-edge transportation approaches with new information, communication, computers, and other technology. ITS should discover consequence routes to enhance the sustainability, safety, and trustworthiness of the entire transportation system utilizing emerging technologies. In this paper, a sustainable safety management framework for connected vehicles is proposed by integrating blockchain. It introduces smart transportation equipment called an AI-enabled vehicle smart device (AVSD) for vehicular communications. AVSD can reduce energy consumption by decreasing the computational costs in vehicular communications. Smart contracts are used to identify vehicles automatically and establish secure communication among vehicles and emergency service stations (ESSs) like hospitals, police stations, and fire stations. The experiment results show that the proposed framework provides a communication environment for sustainable safety and security using the introduced smart transportation device. In conclusion, the proposed blockchain-enabled sustainable safety management framework has the potential to improve safety and sustainability in the transportation industry by creating a secure, decentralized, and transparent platform for managing safety data and promoting safe and sustainable driving behaviors.

42 ENGINEERING↗
DOE OSTI2025

A Novel, Low-Cost, Portable Device for Counterfeit and Noncompliant Refrigerant Detection

The increasing prevalence of counterfeit refrigerants presents significant risks to Heating, Ventilation, Air Conditioning, and Refrigeration (HVACR) systems, including compromised equipment performance, safety hazards, and environmental non-compliance. This report details the development of a novel, cost-effective, and portable detection device designed to accurately identify counterfeit refrigerants. The device utilizes a controlled gas sampling and analysis system within a sealed chamber, ensuring precise measurements while maintaining safety through a purging mechanism. The system features a high-sensitivity sensor integrated with an onboard control module that analyzes gas composition in real-time, providing users with clear visual indicators for refrigerant authenticity. Laboratory validation demonstrated the device’s high accuracy (exceeding 95%) in detecting unauthorized refrigerant blends. Key advantages include affordability, ease of use, rapid response time, and compatibility with a wide range of refrigerants. This solution supports compliance with regulatory frameworks such as the AIM Act, enhances safety in HVACR operations, and mitigates the risks associated with counterfeit refrigerants. Future developments will focus on expanding refrigerant detection capabilities, integrating machine learning for enhanced accuracy, implementing cost-reduction strategies to improve accessibility and market adoption, and optimizing system packaging for enhanced field portability.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2017

Development of a diversity and defense-in-depth strategy for the TerraPower TWR-P Advanced nuclear power plant - 380

A Diversity and Defense in Depth (D3) analysis was performed for the Traveling Wave Reactor, which is a Generation IV fast reactor design. The analysis demonstrated that the current I and C design for TWR-P provides sufficient diversity in the reactor shutdown system, the engineered safety features, and the post-accident monitoring system. In addition, an analysis was performed for the Embedded Digital Devices (EDD) to ensure a postulated Software Common Cause Failure (SWCCF) will not affect the safety functions of the TWR-P I and C system. (authors)

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
DOE OSTI2018

In situ and operando probing of solid–solid interfaces in electrochemical devices

Solid-state electrolytes can offer improved lithium-ion battery safety while potentially increasing the energy density by enabling alkali metal anodes. There have been significant research efforts to improve the ionic conductivity of solid-state electrolytes and the electrochemical performance of all-solid-state batteries; however, the root causes of their poor performance—interfacial reaction and subsequent impedance growth—are poorly understood. This is due to the dearth of effective characterization techniques for probing these buried interfaces. In situ and operando methodologies are currently under development for solid-state interfaces, and they offer the potential to describe the dynamic interfacial processes that serve as performance bottlenecks. Here, this article highlights state-of-the-art solid–solid interface probing methodologies, describes practical limitations, and describes a future for dynamic interfacial characterization.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Innovative approach to counterfeit and noncompliant refrigerant detection: A cost-effective, portable solution

The increasing prevalence of counterfeit and incompatible refrigerants presents significant risks to Heating, Ventilation, Air Conditioning, and Refrigeration (HVAC&R) systems, including compromised equipment performance, safety hazards, and non-compliance. This article details the development of a novel, cost-effective, and portable detection device designed to accurately verify refrigerants. The device utilizes a controlled gas sampling and analysis system within a sealed chamber, ensuring precise measurements while maintaining safety through a purging mechanism. The system features a high-sensitivity sensor integrated with an onboard control module that analyzes gas composition in real-time, providing feedback within a 2-minute duration. Laboratory validation demonstrated the device’s high accuracy (>95 % based on correct identification of compliant vs. non-compliant blends) in detecting unauthorized refrigerant blends. The projected cost of the product stands at ∼ $150, based on the retail pricing of individual components. Laboratory validation demonstrated the device’s high accuracy (>95 % for composition identification, 100 % rejection of tested counterfeit/incorrect blends) in detecting unauthorized refrigerant blends with a response time <2 min. The device correctly identified authentic R-454A/B/C blends and reliably rejected R-407F and closely related counterfeit mixtures. Key advantages include affordability, ease of use, rapid response time, and compatibility with a wide range of refrigerants. This solution supports compliance with regulatory frameworks, enhances safety in HVAC&R operations, and mitigates the risks associated with counterfeit refrigerants.

Counterfeit refrigerants↗
DOE OSTI2014

Nanotechnology and textiles engineered by carbon nanotubes for the realization of advanced personal protective equipments

Carbon nanotubes (CNT) and CNT-based active materials have been used to assemble the gas sensing unit of innovative platforms able to detect toxic atmospheres developing in confined workplaces. The main goal of the project was to realize a full-featured, operator-friendly safety detection and monitoring system based on multifunctional textiles nanotechnologies. The fabricated sensing platform consists of a multiple gas detector coupled with a specifically designed telecommunication infrastructure. The portable device, totally integrated in the workwear, offers several advantages over the conventional safety tools employed in industrial work activities.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2016

Analysis of Reverse Flow Restriction Device to Prevent Dryout Fuel Damage during BWR Instability

Boiling Water Reactors (BWRs) are subjected to instabilities due to thermal hydraulics feedback or coupled Neutronics-thermal hydraulics feedback. Feedback is affected by many reactor parameters that could destabilize the core such as distribution of pressure drop across the core, axial power shape, subcooling level at the core inlet, radial power peaking factor, reactivity coefficients, and others. There are three common modes of instability in BWRs: single channel instability, core-wide instability, and regional instability. Each instability mode could damage the fuel if the power oscillations are left without an intervention like reactor scram. However, the instability problem becomes more dangerous if the automatic reactor scram is lost, like in Anticipated Transient without Scram (ATWS) accidents. A reverse flow restriction device (RFRD) would mitigate this problem. Core simulation using TRACE/PARCS code has been used to examine the potential effect of restricting the flow in the downward direction on mitigation of the power and flow oscillations to increase the safety of BWRs. The presented results demonstrate the ability of the device on limiting flow oscillation amplitude in the one bundle where it is used, on an adjacent bundle without it and reducing the power peak when the flow is low and power is high during BWR power oscillations. This exercise demonstrates the potential of previously described hardware device on preventing clad temperature excursion to keep the fuel safe from dryout damage and provide encouraging results ahead of the planned more detailed investigation where the device is to be used in more bundles up to full core. In the future work it is planned to examine the effect of device installed in a fraction of the bundles on the flow rate in other bundles. Also, the effect on the characteristics of dryout and rewetting and the resulting temperature excursions with and without the device will be given special attention. (authors)

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗