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All sourcesNASA NTRSDOE OSTI
DOE OSTI2018

Dose Estimation in Recycling of Decontamination Soil Due to Fukushima NPS Accident as Coastal Levees - 18138

After the Fukushima Nuclear Power Station accident, large quantities of radiocesium-contaminated soil generated from decontamination activities have been stored in the Fukushima prefecture. To complete the final disposal of decontamination soil, the Ministry of the Environment of Japan presented policy to reduce the disposal volume by using low-level decontamination soil as recycled materials. The use will be limited to civil engineering structures in public projects, such as coastal levee and road embankment, and be managed by the public authority. However, there has been no example or safety assessment of recycling of decontamination soil. To contribute to guideline development for the recycling by the Ministry of the Environment, we conducted the safety assessment for recycling of decontamination soil as coastal levee. First, we evaluated additional doses to workers and the public in the case of construction and service of coastal levee based on Japanese construction standards. From the result, the radioactive cesium concentration level of recycled materials, with which all additional doses meet the radiation criterion of 1 mSv/y, was derived to be 6,800 Bq/kg. For general designs of coastal levee in Japan, additional doses to the public in the case of service were below 10 μSv/y with derived radioactivity level. Finally, the radiation safety for collapse of coastal levee caused by natural disasters was evaluated to be on the safe side. With derived radioactivity level, additional doses in the case of disaster were confirmed to be below 1 mSv/y. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2026

Data for "Photoinduced Chemomimetic Biocatalysis for Enantioselective Intermolecular Radical Conjugate Addition"

Exploiting nature’s catalysts for non-natural transformations that are inaccessible to chemocatalysis is highly desirable but challenging. On the one hand, the widespread nicotinamide-dependent oxidoreductases have not been utilized for single-electron-transfer-induced bimolecular cross-couplings; on the other, the addition of catalytic asymmetric radical conjugate to terminal alkenes remains a challenge owing to strong racemic background reaction and unselective termination of prochiral radical species. Here we report a chemomimetic biocatalysitic approach for construction of alpha-carbonyl stereocentres via an unnatural intermolecular conjugate addition of N-(acyloxy)phthalimides-derived radicals with acceptor-substituted terminal alkenes, by combination of visible-light excitation and nicotinamide-dependent ketoreductases (KREDs). Based on protein crystal structure, we engineered KREDs via a semi-rational mutagenesis strategy to improve reaction outcomes with a small and high-quality variants library. Mechanistic investigations combining wet experiments, crystallographic studies and computational simulations demonstrate that the repurposed biocatalyst can suppress racemic background reaction and unselected side reactions, yielding enantioselectivity that is challenging to achieve by chemocatalysis.

Catalysis↗
DOE OSTI2024

Stress interference in multilayer additive friction stir deposition of AA6061 aluminum

Due to the multilayer deposition nature of metal additive manufacturing processes, each layer being printed experiences the state of thermokinetic and thermomechanical stress that in turn interfere with the state of thermokinetics and thermomechanical stress of subsequently deposited layers. Especially, this multilayer interference significantly affects the resultant properties of the component fabricated using solid-state additive friction stir deposition due to evolution of asymmetric state of planar stress. Due to the lack of comprehensive and suitable in situ diagnosis technique, the complex interference of inter- and multi-layer stresses during additive friction stir deposition was studied in an integrated approach of numerical simulation of fluidic state and experimental probing of stress influenced ultrasonic elastography. The uni-directional and bi-directional layer deposition configurations adopted during additive friction stir deposition result in the generation of constructive and destructive interference of the interlayer stress and hence, asymmetric and symmetric dynamic elasticity distribution respectively within the subsequent layers. With subsequent deposition of additional layers, the odd and even numbers of deposited layers generate asymmetric and nearly symmetric dynamic elasticity distributions.

Yang, Teng↗
NASA NTRS1993

The GAMCIT gamma ray burst detector

The GAMCIT payload is a Get-Away-Special payload designed to search for high-energy gamma-ray bursts and any associated optical transients. This paper presents details on the design of the GAMCIT payload, in the areas of battery selection, power processing, electronics design, gamma-ray detection systems, and the optical imaging of the transients. The paper discusses the progress of the construction, testing, and specific design details of the payload. In addition, this paper discusses the unique challenges involved in bringing this payload to completion, as the project has been designed, constructed, and managed entirely by undergraduate students. Our experience will certainly be valuable to other student groups interested in taking on a challenging project such as a Get-Away-Special payload.

Mccall, Benjamin J.↗
DOE OSTI2024

Toolpath considerations for extrusion: Pellet, filament, concrete, and thermoset

There are a variety of extrusion and deposition-based processes for additive manufacturing, such as fused deposition modeling (FDM), fused filament fabrication (FFF), and directed energy deposition (DED). These processes can use a variety of materials, including thermoplastic pellets, thermoplastic filament, thermoset, concrete, metal wire, metal powder, and more. For all these processes and materials, the underlying toolpath strategies for 3D-printing an object are the same: the object to be printed is sliced into layers, then the layer is optimally fit with toolpaths of a given width, based on specific user settings. However, based on the specific process being used, additional modifiers and toolpathing strategies may be employed to maximize the capabilities of the process and successfully construct an object. This chapter explores the different pathing considerations and additional strategies to be employed in extrusion processes that use thermoplastics, thermosets, and concretes.

Roschli, Alex↗
DOE OSTI2018

ADAPTIVE SURROGATES WITHIN THE RAVEN FRAMEWORK FOR DYNAMIC PROBABILISTIC RISK ASSESSMENT ANALYSIS

The RAVEN code has been under development at the Idaho National Laboratory since 2012. Its main goal is to create a multi-purpose platform for the deploying of all the capabilities needed for Probabilistic Risk Assessment (PRA), Uncertainty Quantification (UQ), data mining analysis and optimization studies. RAVEN has demonstrated a good level of maturity in terms of state-of-art and advanced analysis methodologies. In the past year the RAVEN code has been released as open-source project and is available to download (raven.inl.gov) free of charge. The main subject of this paper is to present a new system within the RAVEN framework to drastically accelerate PRA and UQ analysis using acceleration schemes based on surrogate modeling. This system is based on the heavy usage of surrogate modeling and artificial intelligence algorithms, able to emulate the response of a physical system in closed domains (domains where the surrogate models have been constructed from). The aim of this paper is to show to the community how the employment of surrogate modeling techniques can be a viable solution for the current and future challenges in terms of PRA, UQ and Safety Margins characterizations. In addition, in this manuscript it is presented the construction of a RAVEN new entity named “HybridModel” that is aimed to switch between a high-fidelity code and its linked surrogate, accelerating the PRA and UQ processes without largely reducing the accuracy of the results of the analyses. All these new capabilities will be shown with an application example about a Station Black Out scenario for a prototypical Pressurized Water Reactor (modeled with RELAP5-3D).

97 MATHEMATICS AND COMPUTING↗
NASA NTRS2008

Mars Reconnaissance Orbiter Wrapper Script

The MRO OLVM wrapper script software allows Mars Reconnaissance Orbiter (MRO) sequence and spacecraft engineers to rapidly simulate a spacecraft command product through a tool that simulates the onboard sequence management software (OLVM). This script parses sequence files to determine the appropriate time boundaries for the sequence, and constructs the script file to be executed by OLVM to span the entirety of the designated sequence. It then constructs script files to be executed by OLVM, constructs the appropriate file directories, populates these directories with needed input files, initiates OLVM to simulate the actual command product that will be sent to the spacecraft, and captures the results of the simulation run to an external file for later review. Additionally, the tool allows a user to manually construct the script, if desired, and then execute the script with a simple command line.

Gladden, Roy↗
DOE OSTI2023

Performance of Windows in Walls With Continuous Insulation

Window openings in walls are a significant contributor to poor thermal performance because of thermal bridging through the framing members (e.g., studs, joists, plates, bracing) and because windows lack the thermal properties of insulation. Window installation guidance for walls with continuous insulation (CI) is critical for continued market growth of this energy efficiency technology. This research project offers window manufacturers a starting point and a potential path toward developing installation instructions for windows over CI. The objectives of the research include evaluating the common method for installing windows in walls with CI, as well as establishing acceptance criteria for evaluating the performance of windows installed in walls with and without CI. The research measures: 1. The performance characteristics (e.g., water management, structural integrity) of windows in walls without CI. 2. The performance of different thicknesses and types of CI used in walls. 3. The performance of different types of window assemblies (e.g., double-hung windows, mulled double-hung windows, mulled casement windows, and slider windows) installed over CI. 4. The performance of window flange types (e.g., rigid mounting and less robust flanges) installed over CI. 5. Installing windows over CI using baseline installation instructions versus window manufacturer installation instructions. The project’s sequential testing protocol consists of the following: • A water penetration resistance testing adapted from two ASTM standards: E331 (uniform static air pressure in four steps) and E547 (cyclic static air pressure) • A temperature cycling adapted from ASTM E2264 Method B (convective hot air) • A service condition wind loading test adapted from ASTM E330 • A six-month vertical displacement observation phase prior to the structural performance testing • A final water penetration resistance test after vertical displacement observation • A structural performance test adapted from ASTM E330. Key research findings include: • The criterion for passing a water penetration resistance test is that there is no water overflowing at the interior face of the studs. If there is any bubbling or slight pooling of water at the sill, then it must recede after the pressure is removed. Excessive leakage and/or water leaking to the interior face of the framing around the window constitutes a failure. • All single double-hung windows installed directly to lumber or over oriented strand board passed all test protocols. • For most wall specimens, the test results showed that the use of foam sheathing did not affect the performance of the window for water leakage. • All wall specimens underwent temperature cycling. The results indicated that temperature cycling had little to no effect on windows installed over foam sheathing. • For wall specimens that underwent six-month vertical displacement monitoring, the results showed that windows installed over foam sheathing do not sag over time. • The single-hung and double-hung windows installed using window manufacturer installation instructions passed the structural performance test, compared to failures observed in windows that were installed using generic installation instructions. The generic and manufacturer installation methods differed on the following construction details: type of fasteners, fastening patterns on the flanges, and window shimming details. • Additional testing is required to determine methods to improve structural pressure performance of slider windows. Potential solutions that would require additional testing may include fastener spacing, different types of fasteners, masonry window clips, construction adhesive, foam sealant, stronger window flange material, and/or straps.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2025

Does the Z boson have a lighter cousin?

In the quenched electroweak theory on the lattice I construct a set of physical states which overlap the physical photon and Z boson states. This is done by employing eigenstates of the covariant lattice Laplacian, in addition to the Higgs and lattice link variables, to construct gauge invariant vector boson creation operators. Diagonalizing the transfer matrix in the subspace of Hilbert space spanned by this set yields a massless photon and massive Z particle, as expected. But in the numerical data there is evidence for more vector bosons in the spectrum, albeit with considerable uncertainty in their masses, with the lowest finite mass particle in the range of 3–4 GeV. Published by the American Physical Society 2025

Greensite, Jeff (ORCID:0000000317209436)↗
NASA NTRS1992

Status of the Whipple Observatory Cerenkov air shower imaging telescope array

Recently the power of the Cerenkov imaging technique in Very High Energy gamma-ray astronomy was demonstrated by the detection of the Crab nebula at high statistical significance. In order to further develop this technique to allow the detection of weaker or more distant sources a second 10 m class reflector was constructed about 120 m from the original instrument. The addition of the second reflector will allow both a reduction in the energy threshold and an improvement in the rejection of the hadronic background. The design and construction of the second reflector, Gamma Ray Astrophysics New Imaging TElescope (GRANITE) is described.

Akerlof, C. W.↗
NASA NTRS1992

Shuttle Rocket Motor Program: NASA should delay awarding some construction contracts. Report to the Chair, Subcommittee on Government Activities and Transportation, Committee on Government Operations, House of Representatives

Even though the executive branch has proposed terminating the Advanced Solid Rocket Motor (ASRM) program, NASA is proceeding with all construction activity planned for FY 1992 to avoid schedule slippage if the program is reinstated by Congress. However, NASA could delay some construction activities for at least a few months without affecting the current launch data schedule. For example, NASA could delay Yellow Creek's motor storage and dock projects, Stennis' dock project, and Kennedy's rotation processing and surge facility and dock projects. Starting all construction activities as originally planned could result in unnecessarily incurring additional costs and termination liability if the funding for FY 1993 is not provided. If Congress decides to continue the program, construction could still be completed in time to avoid schedule slippage.

Source record↗
DOE OSTI2022

Strengthening the Security of Operational Technology: Understanding Contemporary Bill of Materials

The evolution of cyber-physical infrastructure has made its security more challenging. The last few years have witnessed a convergence of hardware and software segments in various domains, including operational technology (OT) which is responsible for carrying out critical tasks such as monitoring and controlling power grids, nuclear plants, transportation, and emergency services. Both hardware and software encapsulate numerous open source and proprietary subcomponents, making it crucial for end-users to understand the composition of the products they are using. For example, wind turbines incorporate thousands of lines of code (software) used for the turbine's design, planning, operation, and analytics in addition to the numerous hardware subcomponents that construct it. Due to the highly complex nature of software and hardware, knowledge of the components and subcomponents is required to mitigate cyber vulnerabilities and defend against cyberattacks. There has also been a transformation from a traditional linear supply chain into a global, dynamic, diverse, and interconnected system. The digitization of the supply chain makes it easier to find and exploit vulnerabilities. Critical infrastructures (e.g., power grids, oil, natural gas, water, and wastewater) rely on OT to function, and if the OT is compromised, equipment damage and potential interruption of services could result. A significant security measure to protect OT systems from disruption is to develop a supply chain bill of materials (BoM) corresponding to the software and hardware used in OT, along with attestations amongst vendors and asset owners. A supply chain BoM is a proactive way to understand the inherent vulnerabilities in the system and mitigate them in advance of being exploited. BoMs bolster the trust placed in the digital infrastructure and enhance software supply chain security by sustaining the management of component obsolescence and compliance, along with the seclusion of unsafe segments of a specific product. Adopting BoM tools is becoming increasingly important across various government sectors, as evidenced by the recent U.S. executive order on cybersecurity (NIST 2021). This paper aims to classify BoMs based on structure, functionality, component type, and architecture. The work also discusses case studies to further highlight the benefits of BoMs. In addition, it identifies missing pieces in existing BoM implementations so that future research may identify bounds on where it could expect to make improvements and directly enable researchers to identify promising areas for exploration. Further, the authors provide valuable recommendations to tool developers, researchers, and standardizing organizations (policymakers), additionally benefitting critical infrastructure owners and government executives. This aids in paving a path for future work, thereby, providing suggestions to determine a tool for consumers that best suit their needs.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2015

Additive Manufacturing Materials Study for Gaseous Radiation Detection

Additive manufacturing (AM) techniques may lead to improvements in many areas of radiation detector construction; notably the rapid manufacturing time allows for a reduced time between prototype iterations. The additive nature of the technique results in a granular microstructure which may be permeable to ingress by atmospheric gases and make it unsuitable for gaseous radiation detector development. In this study we consider the application of AM to the construction of enclosures and frames for wire-based gaseous radiation tracking detectors. We have focussed on oxygen impurity ingress as a measure of the permeability of the enclosure, and the gas charging and discharging curves of several simplistic enclosure shapes are reported. A prototype wire-frame is also presented to examine structural strength and positional accuracy of an AM produced frame. We lastly discuss the implications of this study for AM based radiation detection technology as a diagnostic tool for incident response scenarios, such as the interrogation of a suspect radiation-emitting package. (authors)

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2024

Understanding the Challenges of Financing Modular Construction: A Case Study for Prospective Multifamily Units

Compared to traditional site build, modular construction can significantly shorten construction schedules and speed income generation. Modular construction may also reduce construction costs. Yet access to commercial financing remains one of the most significant barriers to modular construction. Materials must be purchased, and production lines reconfigured for each project months ahead of fabrication. Materials alone can be 60% or more of the total cost of production. As a result, manufacturers require large upfront deposits—often 30% or more of the off-site contract. In addition, the capital-intensive nature of modular construction requires frequent progress payments for manufacturers to maintain cash flow. For those lenders willing to fund modular projects, many require the developer to share more of the risk. This may include the developer paying for line reservation fees and material deposits 3–6 months prior to production. Because these are unsecured loans, interest rates may be higher and loan amounts lower. As suppliers, modular manufacturers discourage retainage. Together, these and other factors may contribute to higher equity requirements for the developer—particularly at the beginning of the project.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2014

DMLC tracking and gating can improve dose coverage for prostate VMAT

Purpose: To assess and compare the dosimetric impact of dynamic multileaf collimator (DMLC) tracking and gating as motion correction strategies to account for intrafraction motion during conventionally fractionated prostate radiotherapy. Methods: A dose reconstruction method was used to retrospectively assess the dose distributions delivered without motion correction during volumetric modulated arc therapy fractions for 20 fractions of five prostate cancer patients who received conventionally fractionated radiotherapy. These delivered dose distributions were compared with the dose distributions which would have been delivered had DMLC tracking or gating motion correction strategies been implemented. The delivered dose distributions were constructed by incorporating the observed prostate motion with the patient's original treatment plan to simulate the treatment delivery. The DMLC tracking dose distributions were constructed using the same dose reconstruction method with the addition of MLC positions from Linac log files obtained during DMLC tracking simulations with the observed prostate motions input to the DMLC tracking software. The gating dose distributions were constructed by altering the prostate motion to simulate the application of a gating threshold of 3 mm for 5 s. Results: The delivered dose distributions showed that dosimetric effects of intrafraction prostate motion could be substantial for some fractions, with an estimated dose decrease of more than 19% and 34% from the planned CTVD{sub 99%} and PTV D{sub 95%} values, respectively, for one fraction. Evaluation of dose distributions for DMLC tracking and gating deliveries showed that both interventions were effective in improving the CTV D{sub 99%} for all of the selected fractions to within 4% of planned value for all fractions. For the delivered dose distributions the difference in rectum V{sub 65%} for the individual fractions from planned ranged from −44% to 101% and for the bladder V{sub 65%} the range was −61% to 26% from planned. The application of tracking decreased the maximum rectum and bladder V{sub 65%} difference to 6% and 4%, respectively. Conclusions: For the first time, the dosimetric impact of DMLC tracking and gating to account for intrafraction motion during prostate radiotherapy has been assessed and compared with no motion correction. Without motion correction intrafraction prostate motion can result in a significant decrease in target dose coverage for a small number of individual fractions. This is unlikely to effect the overall treatment for most patients undergoing conventionally fractionated treatments. Both DMLC tracking and gating demonstrate dose distributions for all assessed fractions that are robust to intrafraction motion.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2016

Design and characterization of a novel toroidal split-ring resonator

The design and characterization of a novel toroidal split-ring resonator (SRR) are described in detail. In conventional cylindrical SRRs, there is a large magnetic flux within the bore of the resonator. However, there also exists a non-negligible magnetic flux in the free space surrounding the resonator. The energy losses associated with this radiated power diminish the resonator’s quality factor. In the toroidal SRR, on the other hand, the magnetic field lines are strongly confined within the bore of the resonator resulting in high intrinsic quality factors and stable resonance frequencies without requiring additional electromagnetic shielding. This paper describes the design and construction of a toroidal SRR as well as an experimental investigation of its cw response in the frequency-domain and its time-domain response to a rf pulse. Additionally, the dependence of the toroidal SRR’s resonant frequency and quality factor on the strength of inductive coupling to external circuits is investigated both theoretically and experimentally.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2025

Bonneville Dam Powerhouse 2 Gatewell Improvement Post Construction Evaluation (Final Report)

Modifications to vertical barrier screens (VBS) and the addition of concrete corbels to improve passage conditions for juvenile salmonids in the gatewells of Bonneville Dam’s second powerhouse (B2) were completed prior to the 2024 passage season. To evaluate the effectiveness of those modifications, PNNL carried out a post construction evaluation to contrast fish condition and mortality between two turbine unit operational ranges within the peak efficiency range. A block-treatment study design was implemented in 2024 to contrast descaling and mortality of juvenile salmonids sampled in the juvenile fish facility following exposure to turbine operations (middle versus upper 1% peak efficiency range) during spring and summer passage periods. In spring, 1.96% of juvenile salmonids sampled during mid-1% operations were descaled and 0.46% were mortalities. Of those sampled during upper 1% unit operations in spring, 2.90% were descaled and 0.95% were mortalities. Although these differences appeared to be meaningful, substantial exceedances of the upper 1% limit occurred during two treatment blocks of the spring study period. Fish collected during the upper 1% treatment of these two blocks experienced substantially higher rates of descaling and mortality compared to those collected during mid-1% treatments. Censoring these two upper 1% samples from the spring study period resulted in upper 1% descaling and mortality rates that were statistically similar to those from the mid-1% treatment. During the summer study period, 0.99% of juveniles sampled during mid-1% operations were descaled and 0.33% suffered mortality; these rates were significantly lower than the descaling (2.80%) and mortality (1.73%) rates observed during upper 1% treatments. Comparing the results from the 2024 study to those from the historical (2008–2013) baseline of unmodified units revealed that the descaling and mortality rates observed during upper 1% operations in spring 2024 were near the upper end of the historic range observed for mid-1% operations. Spring 2024 upper 1% descaling and mortality rates were below, or well below the median of historical mid and upper 1% (combined) rates, which suggests that the modifications have had a positive effect. Summer 2024 upper 1% descaling and mortality rates were at or above the top of the range of historical mid 1% and above or well above the median of historical mid and upper 1% (combined) rates. It is important to keep in mind that 2024 is a single year when considering these comparisons. Additional study could help confirm these results or seek a level of operation that achieves the desired outcomes for fish.

13 HYDRO ENERGY↗
DOE OSTI2016

The design and research of anti-color-noise chaos M-ary communication system

Previously a novel chaos M-ary digital communication method based on spatiotemporal chaos Hamilton oscillator has been proposed. Without chaos synchronization circumstance, it has performance improvement in bandwidth efficiency, transmission efficiency and anti-white-noise performance compared with traditional communication method. In this paper, the channel noise influence on chaotic modulation signals and the construction problem of anti-color-noise chaotic M-ary communication system are studied. The formula of zone partition demodulator’s boundary in additive white Gaussian noise is derived, besides, the problem about how to determine the boundary of zone partition demodulator in additive color noise is deeply studied; Then an approach on constructing anti-color-noise chaos M-ary communication system is proposed, in which a pre-distortion filter is added after the chaos baseband modulator in the transmitter and whitening filter is added before zone partition demodulator in the receiver. Finally, the chaos M-ary communication system based on Hamilton oscillator is constructed and simulated in different channel noise. The result shows that the proposed method in this paper can improve the anti-color-noise performance of the whole communication system compared with the former system, and it has better anti-fading and resisting disturbance performance than Quadrature Phase Shift Keying system.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗