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At least 811 records · Page 45

scraps: An open-source Python-based analysis package for analyzing and plotting superconducting resonator data

We present "scraps" (SuperConducting Analysis and Plotting Software), a Python package designed to aid in the analysis and visualization of large amounts of superconducting resonator data, specifically complex transmission as a function of frequency, acquired at many different temperatures and driving powers. The package includes a least-squares fitting engine as well as a Monte-Carlo Markov Chain sampler for sampling the posterior distribution given priors, marginalizing over nuisance parameters, and estimating covariances. A set of plotting tools for generating publication-quality figures is also provided in the package. Lastly, we discuss the functionality of the software and provide some examples of its utility on data collected from a niobium-nitride coplanar waveguide resonator fabricated at Argonne National Laboratory.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

Research on the Corrosion Behavior of X70 Pipeline Steel Under Coupling Effect of AC + DC and Stress

The coupling effect of stray AC (alternating current) + DC (direct current) and tensile stress-induced X70 pipeline corrosion is complicated with its mechanism uncovered. In this work, the corrosion behavior of X70 pipeline steel under three different corrosion (including an individual AC corrosion, mixed AC + 150 MPa tensile stress corrosion, coupling effect of AC + a 30 A/m{sup 2} DC interference and 150 MPa tensile stress corrosion) conditions in Dagang soil simulated solution was investigated by COMSOL Multiphysics software simulation, electrochemical tests, scanning electron microscope and other techniques. The results indicated that with the increase in AC density, the open-circuit potential of the X70 steel samples was negatively shifted and corrosion rate increased in three different corrosion conditions. The corrosion rates of X70 steel samples under individual AC interference were almost unchanged when 150.9 MPa tensile stress was applied. When applying 30 A/m{sup 2} DC interference, the corrosion rate of X70 steel increases significantly. Therefore, the factors affecting corrosion performance of X70 pipeline steel were DC > AC > stress. Under individual AC interference, uniform corrosion occurred on the X70 steel at an AC current density of less than 30 A/m{sup 2}, while the pitting corrosion occurred at an AC current density of greater than 100 A/m{sup 2}. The application of tensile stress and DC had a certain inhibitory effect on pitting corrosion.

36 MATERIALS SCIENCE↗

Evaluating the Impact of Price-Responsive Load on Power Systems Using Integrated T&D Simulation

This paper explores the differences between simulating price-responsive load (PRL) interactions with power systems using integrated transmission and distribution (T&D) models and transmission-only (T-only) models. This analysis uses the Integrated Grid Modeling System (IGMS) software to capture 'ISO-to-appliance' simulations using a synthetic T&D model built on the PJM 5-Bus transmission network with multiple full-scale taxonomy feeders that include physics-based models of thousands of customers and PRLs. The results show important differences in the impacts of PRLs between integrated T&D and T-only models. Experiments with the synthetic integrated T&D dataset demonstrated that integrated T&D simulation revealed notably larger differences between the PRL and no-PRL cases for load, and prices compared to T-only simulation. Similarly, differences are observed between the price response of individual buildings and distribution feeders and the corresponding transmission bus in the integrated T&D simulations, which are difficult to capture in traditional T-only simulations.

24 POWER TRANSMISSION AND DISTRIBUTION↗

Building envelope anomaly characterization and simulation using drone time-lapse thermography

Defects in building envelopes deteriorate over time without being visible to the human eye, while significantly impacting energy performance due to unaccounted heat transfer. Defects can be characterized in the infrared (IR) spectrum. However, IR readings are typically recorded at singular points in time, when in several cases anomalies can only be revealed at specific times of the day, possibly in different seasons of the year. This paper presents a novel workflow for 3D envelope defect characterization and modeling using aerial time-lapse IR data collection using drones. A comprehensive envelope thermal profile is developed for a case study building employing the photogrammetry software Agisoft Photoscan, which generates temporal IR inspections of building skins using multiple thermography orthomosaics. Point-cloud data is then translated into a CAD model and thermal zones for whole Building Energy Modeling (BEM) using Honeybee as a frontend to EnergyPlus to showcase the potential of inclusion of detailed 4D data. Envelope contributions in this case study’s anomalies showed heat losses of 6447.6 kWh, and Energy Use Intensity (EUI) differences of ~2 kWh/m 2 /year from the baseline. Finally, why there is currently little translation of this work in BEM software is discussed, while identifying limitations and future research in the employment of time-lapse thermography using drones for more accurate building envelope inspection and modeling.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Hybrid Tandem Photovoltaics

Tandem solar cell structures are the only strategy demonstrated to surpass the detailed balance efficiency limit of high-quality single-junction solar cells. To continue to improve the efficiencies of cost-effective terrestrial solar power, hybrid tandems of dissimilar subcells are being considered by many around the world, especially designs that incorporate silicon solar cells as a bottom subcell. In this project, we studied a wide variety of tandem design possibilities including those with three-terminal (3T) and four-terminal (4T) configurations. The use of 3T and 4T designs could be useful for efficient and economical hybrid tandem designs that utilize the best available subcell materials such as emerging perovskite materials. Three-terminal configurations, in particular, have not been sufficiently studied previously. We have laid the foundational groundwork in this project for understanding the operation of 3T tandems: developing a taxonomy for naming, a methodology for measuring and interconnecting, and models for simply characterizing 3T tandems. Electrical and optical subcell coupling between the subcells was also measured and modeled. An important part of this work was the fabrication of novel example tandem structures, including 4T GaAs/Si, 3T GaInP/Si, 3T GaAs/Si, and 3T GaInP/GaAs devices. Using these high-quality tandem cells, we have been able to clearly demonstrate the achievability of high-efficiencies, and subtle physical effects such as photon recycling and luminescent coupling. We have developed and demonstrated essential building-block tools such as transparent conductive adhesives (TCA) and 3T silicon bottom cells with interdigitated back contacts (IBC) that can also be used in many other tandem designs. We have tested the reliability of these tools and devices under standardized testing and outdoor measurements. We have found 4T GaAs/Si tandems to be relatively straightforward to fabricate and robust in real-world outdoor conditions. While we have demonstrated working hybrid 3T III-V/TCA/Si IBC tandems, we experienced low yields even with our best process flows yet. Further work is still needed to improve the processing yield of these devices. We therefore also created tandem cells using an all-III-V 3T tandem process which was very robust with high yields, allowing for the creation of voltage-matched strings in many different configurations using 8 nearly identical 3T tandems. Using these robust 3T tandem examples, we were able measure and precisely characterize 3T tandem behaviors to predict their operation under changing spectrum and temperature. The optoelectronic equivalent-circuit model was shown to be very general and applicable to hybrid tandems, and encompassed the operation 3T Si IBC cells. This general model has been distributed to the public in as open-source Python-based software called PVcircuit. We have calculated the implications of these new tandem device designs on the real-world energy production and shown how the relative performance of different tandem configurations is situational and can be engineered using the tools developed here.

14 SOLAR ENERGY↗

SU-F-T-266: Dynalogs Based Evaluation of Different Dose Rate IMRT Using DVH and Gamma Index

Purpose: This work investigates the impact of low and high dose rate on IMRT through Dynalogs by evaluating Gamma Index and Dose Volume Histogram. Methods: The Eclipse™ treatment planning software was used to generate plans on prostate and head and neck sites. A range of dose rates 300 MU/min and 600 MU/min were applied to each plan in order to investigate their effect on the beam ON time, efficiency and accuracy. Each plan had distinct monitor units per fraction, delivery time, mean dose rate and leaf speed. The DVH data was used in the assessment of the conformity and plan quality.The treatments were delivered on Varian™ Clinac 2100C accelerator equipped with 120 leaf millennium MLC. Dynalogs of each plan were analyzed by MATLAB™ program. Fluence measurements were performed using the Sun Nuclear™ 2D diode array and results were assessed, based on Gamma analysis of dose fluence maps, beam delivery statistics and Dynalogs data. Results: Minor differences found by adjusted R-squared analysis of DVH’s for all the plans with different dose rates. It has been also found that more and larger fields have greater time reduction at high dose rate and there was a sharp decrease in number of control points observed in dynalog files by switching dose rate from 300 MU/min to 600 MU/min. Gamma Analysis of all plans passes the confidence limit of ≥95% with greater number of passing points in 300 MU/min dose rate plans. Conclusion: The dynalog files are compatible tool for software based IMRT QA. It can work perfectly parallel to measurement based QA setup and stand-by procedure for pre and post delivery of treatment plan.

60 APPLIED LIFE SCIENCES↗

SU-F-T-22: Clinical Implications When Using TG-186 (ACE) Heterogeneity Software

Purpose: The purpose of this study is to compare dosimetric calculations using traditional TG-43 formalism and Oncentra Brachy Advanced Collapsed cone Engine (ACE) TG-186 calculation algorithm in clinical setting. Methods: We analyzed dosimetry of four patients treated with accelerated partial breast irradiation using a multi-channel intracavitary device (SAVI). All patients were treated to 34 Gy in 10 fractions using a high-dose-rate (192) Ir source. The plans were designed and treated using the TG-43 model. ACE was used to assess the effect heterogeneity correction on various dosimetric parameters. Mass density was estimated using Hounsfield units. Results: Compared to TG-43 formalism, ACE estimated lower doses to targets and organs at risk. The mean difference was 19.8% (range 15.3–24.1%) for PTV-eval V200, 12.0% (range 9.7–17.7%) for PTV-eval V150, 4.3% (range 3.3–6.5%) for PTV-eval D95, 3.3% (range 1.4–5.4%) for PTV-eval D90, 5.4% (range 2.9–9.9%) for maximum rib dose, and 5.7% (2.4–7.4%) for maximum skin dose. There was no correlation between the magnitude of the difference and the PTV-eval volume, air volume, or tissue-applicator conformance. Conclusion: Based on our preliminary study, the TG-43 algorithm appears to overestimate the dose to targets and organs at risk when compared to the ACE TG-186 software. We hypothesize that air adjacent to the SAVI struts contributes to lack of scatter thereby contributing a significant difference in dose calculation when using ACE. We believe that ACE calculation provides a more realistic isodose distribution than TG-43. We plan to further investigate the impact of heterogeneity correction on brachytherapy planning for a wide variety of clinical scenarios, include skin, cervix/uterus, prostate, and lung.

60 APPLIED LIFE SCIENCES↗

SU-G-BRC-06: Evaluation of a Novel Radiosurgery Software for Treating Multiple Brain Metastases Simultaneously in a Single Fraction

Purpose: To evaluate a new, automated brain metastases planning software designed to treat up to ten brain metastases simultaneously. Methods: We treated 61 patients with multiple brain metastases using the Elements software by BrainLab (Munich, Germany). Patients had between 2–10 metastases ranging from 0.01–8.64 cc. Dose prescription was 18–24 Gy. Plans use up to 5 non-coplanar arcs with a single isocenter at the metastases’ center of mass. The high degree of automation shortens the planning time to 15–20 minutes per patient.For comparison we planned 21 of the patients using Rapid Arc (Varian, Palo Alto CA) (RA). We used two coplanar arcs so as to keep planning times comparable to the Elements. We also planned 8 patients using iPlan software (BrainLab). We compared conformity index (CI), volume of brain receiving over 12 Gy (V{sub 12}) and mean brain dose (MBD) for the three different planning systems (TPSs). Results: Plans from all TPSs were judged clinically acceptable. V{sub 12} and MBD were not statistically significantly different between TPSs.CI between RA and Elements was similar, however for iPlan CI was significantly worse compared to both RA and Elements (p<0.001). RA plans took approximately 40 minutes to plan (despite fusion and contouring being done in the Elements), and iPlan plans over an hour each. Delivery times were approximately 30 minutes for Elements, 10 minutes for RA, and up to 300 minutes for iPlan. Conclusion: Elements plans had good CI values and low brain doses. While treatment times for Elements were longer than for RA, 30 minutes is a significant improvement over conventional radiosurgery techniques where each metastasis is treated individually and delivery times to 10 metastases are close to 300 minutes.BrainLab Elements is a novel software allowing fast, automated planning and efficient irradiation of multiple brain metastases with minimal dose to healthy brain.

60 APPLIED LIFE SCIENCES↗

Design and performance analysis of a Swirl Pintle injector for a 1 MW th pressurized oxy-coal combustor

Pressurized Oxy-coal combustion has the potential to achieve high thermal efficiency by recovering the latent heat of steam from flue gases and providing options for up to 95% carbon capture. Here, this study proposes a novel burner technology for pressurized oxy-coal combustion and investigates its operability. Three burner versions are designed and tested; no swirl, swirl numbers 0.9 and 1.2 to identify optimum design parameters and performance. A commercially available Dantec Dynamics software is used to conduct the shadowgraph experiments to observe burner performance. Coal water slurry is used as fuel with three different slurry ratios where the coal percentage by weights were 30, 40 and 50. Droplet size, distribution, spray angle and jet breakup lengths are measured and analyzed to quantify the performance. The study found that increasing the swirl number enhanced atomization. Implementing swirlers allowed the jet to spread through faster primary jet separation, thus improving atomization. In addition, higher slurry ratios improved the generation of smaller particles. However, it was also found that excessive increases in oxidizer momentums negatively impact the atomization process by jet shrinkage. The study concluded that operating a pintle burner at 1.2 swirl conditions with a 40/60 slurry ratio produces optimum performance.

42 ENGINEERING↗

Numerical modeling of hydrogen mixing in a direct-injection engine fueled with gaseous hydrogen

Hydrogen is considered as one of the most promising options to achieve effective decarbonization of the energy and transportation sectors. As such, it has recently been receiving increasing attention because of its promising potential as an energy carrier for advanced energy and propulsion systems. With a focus on internal combustion engines, direct injection (DI) of gaseous hydrogen during the compression stroke offers great potential for high engine efficiency and specific power while reducing the risk of backfiring and pre-ignition issues. Therefore, many experimental and numerical efforts have recently been dedicated to understanding the physical and chemical behaviors of hydrogen in engine during mixing and combustion. This study focuses on computational fluid dynamics (CFD) modeling of the hydrogen DI process in a hydrogen optical research engine. Under the conditions studied, gaseous hydrogen is injected into the combustion chamber via a centrally located single-hole injector at a pressure of 100 bar. Two configurations, namely low-and high-tumble, are investigated to understand the impact of different in-cylinder flow patterns on the fuel-air mixture preparation. Simulations are carried out using the commercial CFD software CONVERGE. Here, the in-cylinder turbulence is modeled with an unsteady Reynolds-averaged Navier-Stokes (URANS) formulation closed by the renormalization group (RNG) k-ε model. Several numerical methods and model constants, including but not limited to turbulent Schmidt number, are evaluated. The numerical results are systematically compared against experimental measurements of velocity and hydrogen concentration fields on the vertical center plane to assess the performance of the CFD model, unveil the physics of hydrogen mixing, and establish best practices for modeling hydrogen DI under relatively high injection pressure conditions.

33 ADVANCED PROPULSION SYSTEMS↗

Spatial modeling algorithms for reactions and transport in biological cells

Biological cells rely on precise spatiotemporal coordination of biochemical reactions to control their functions. Such cell signaling networks have been a common focus for mathematical models, but they remain challenging to simulate, particularly in realistic cell geometries. Here we present Spatial Modeling Algorithms for Reactions and Transport (SMART), a software package that takes in high-level user specifications about cell signaling networks and then assembles and solves the associated mathematical systems. SMART uses state-of-the-art finite element analysis, via the FEniCS Project software, to efficiently and accurately resolve cell signaling events over discretized cellular and subcellular geometries. We demonstrate its application to several different biological systems, including yes-associated protein (YAP)/PDZ-binding motif (TAZ) mechanotransduction, calcium signaling in neurons and cardiomyocytes, and ATP generation in mitochondria. Throughout, we utilize experimentally derived realistic cellular geometries represented by well-conditioned tetrahedral meshes. These scenarios demonstrate the applicability, flexibility, accuracy and efficiency of SMART across a range of temporal and spatial scales.

59 BASIC BIOLOGICAL SCIENCES↗

Development of models for exchange of electronic documents

The report presents a model for exchange of electronic documents between different government administrations. It defines electronic messages that are transmitted between them and the way that messages should be processed by software systems. The proposed approach is sufficiently general and allows use of the best applicable information technologies such as data presentation structures and communication protocols. Within the study, a simple implementation of the model is implemented and deployed in various government administrations in Republic of Bulgaria.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

Passive neutron coincidence counting with plastic scintillators for the characterization of radioactive waste drums

The quantification of radioactive material is essential in the fields of safeguards, criticality control of nuclear processes, dismantling of nuclear facilities and components, or radioactive waste characterization. The Nuclear Measurement Laboratory (LMN) of CEA is involved in the development of time-correlated neutron detection techniques using plastic scintillators. Usually, 3He proportional counters are used for passive neutron coincidence counting owing to their high thermal neutron capture efficiency and gamma insensitivity. However, the global {sup 3}He shortage in the past few years has made these detectors extremely expensive. In addition, contrary to {sup 3}He counters for which a few tens of microseconds are needed to thermalize fast neutrons, in view to maximize the {sup 3}He(n,p){sup 3}H capture cross section, plastic scintillators are based on elastic scattering and therefore the light signal is formed within a few nanoseconds, correlated pulses being detected within a few dozen- or hundred nanoseconds. This time span reflects fission particles time of flight, which allows reducing accordingly the duration of the coincidence gate and thus the rate of random coincidences, which may totally blind fission coincidences when using {sup 3}He counters in case of a high (α,n) reaction rate. However, plastic scintillators are very sensitive to gamma rays, requiring the use of a thick metallic shield to reduce the corresponding background. Cross talk between detectors is also a major issue, which consists on the detection of one particle by several detectors due to elastic or inelastic scattering, leading to true but undesired coincidences. Data analysis algorithms are tested to minimize cross-talk in simultaneously activated detectors. The distinction between useful fission coincidences and the correlated background due to cross-talk, (α,n) and induced (n,2n) or (n,n'γ) reactions, is achieved by measuring 3-fold coincidences. The performances of a passive neutron coincidence counting system for radioactive waste drums using plastic scintillators have been studied using the Monte Carlo radiation transport code MCNPX-PoliMi v2.0 coupled to data processing algorithms developed with ROOT data analysis software. In addition to the correlated background, accidental coincidences are taken into account in the simulation by randomly merging pulses from different calculations with fission and (α,n) sources. (authors)

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

Automated Metadata Extraction: Challenges and Opportunities

Proper application of the FAIR data principles is what separates a vibrant data ecosystem, in which research data are frequently shared and reused, from a lifeless data graveyard. Automated metadata extraction systems have been proposed as a means of bolstering the findability, interoperability, and reusabil- ity of data repositories with little or no human intervention. These extraction systems mine metadata by crawling a repository and applying lightweight extractors that, for various types of file (e.g., image, CSV file), extract or synthesize relevant attributes. In practice, however, the automated creation of generally useful metadata is fraught with challenges. Data consumers may have different perspectives as to what metadata representations are useful, the standards for recording metadata tend to change over time, and the software model for processing updates can introduce unnecessary human and computational effort. Thus, generalizing extraction for a broad audience of data consumers is a difficult and relatively unsolved problem.In this work, we explore these challenges faced by extraction systems in the context of constructing our own extraction system for science data. We first define the metadata extraction problem and provide context to the issues faced in generalizing metadata. Additionally, we identify potential research directions to help alleviate many of these challenges for all automated extraction systems. Ultimately, this work represents a first step in designing ubiquitous metadata extraction systems that can maximize the value of research data while minimizing the human efforts required in doing so.

Skluzacek, Tyler↗

FunM2C: A Filter for Uncertainty Visualization of Multivariate Data on Multi-Core Devices

Uncertainty visualization is an emerging research topic in data visualization because neglecting uncertainty in visualization can lead to inaccurate assessments. In this paper, we study the propagation of multivariate data uncertainty in visualization. Although there have been a few advancements in probabilistic uncertainty visualization of multivariate data, three critical challenges remain to be addressed. First, the state-of-the-art probabilistic uncertainty visualization framework is limited to bivariate data (two variables). Second, existing uncertainty visualization algorithms use computationally intensive techniques and lack support for cross-platform portability. Third, as a consequence of the computational expense, integration into production visualization tools is impractical. In this work, we address all three issues and make a threefold contribution. First, we take a step to generalize the state-of-the-art probabilistic framework for bivariate data to multivariate data with an arbitrary number of variables. Second, through utilization of VTK-m’s shared-memory parallelism and cross-platform compatibility features, we demonstrate acceleration of multivariate uncertainty visualization on different many-core architectures, including OpenMP and AMD GPUs. Third, we demonstrate the integration of our algorithms with the ParaView software. We demonstrate the utility of our algorithms through experiments on multivariate simulation data with three and four variables.

Hari, Gautam↗

DEPRECATED BSM-Learning (Bioenergy Scenario Model-Learning) [SWR-09-09]

This repository was archived by the owner on Jun 30, 2026. It is now read-only. This DEPRECATED software is a learning model excerpted from NREL's BSM (Bioenergy Scenario Model) that can be used to examine effects of different learning rates and different techno-economics on industry evolution.

Peterson, Steve↗

IDAC-Dose 2.1, an internal dosimetry program for diagnostic nuclear medicine based on the ICRP adult reference voxel phantoms

To date, the estimated radiation-absorbed dose to organs and tissues in patients undergoing diagnostic examinations in nuclear medicine is derived via calculations based on models of the human body and the biokinetic behaviour of the radiopharmaceutical. An internal dosimetry computer program, IDAC-Dose2.1, was developed based on the International Commission on Radiological Protection (ICRP)-specific absorbed fractions and computational framework of internal dose assessment given for reference adults in ICRP Publication 133. The program uses the radionuclide decay database of ICRP Publication 107 and considers 83 different source regions irradiating 47 target tissues, defining the effective dose as presented in ICRP Publications 60 and 103. The computer program was validated against another ICRP dosimetry program, Dose and Risk Calculation (DCAL), that employs the same computational framework in evaluation of occupational and environmental intakes of radionuclides. IDAC-Dose2.1 has a sub-module for absorbed dose calculations in spherical structures of different volumes and composition; this sub-module is intended for absorbed dose estimates in radiopharmaceutical therapy. For nine specific alpha emitters, the absorbed dose contribution from their decay products is also included in the committed absorbed dose calculations. The absorbed doses and effective dose of 131 I-iodide determined by IDAC-Dose2.1 were validated against the dosimetry program DCAL, showing identical results. IDAC-Dose2.1 was used to calculate absorbed doses for intravenously administered 18 F-FDG and orally administered 99m Tc-pertechnetate and 131 I-iodide, three frequently used radiopharmaceuticals. Using the tissue weighting factors from ICRP Publication 103, the effective dose per administered activity was estimated to be 0.016 mSv/MBq for 18 F-FDG, 0.014 mSv/MBq for 99m Tc-pertechnetate, and 16 mSv/MBq for 131 I-iodide. The internal dosimetry program IDAC-Dose2.1 was developed and applied to three radiopharmaceuticals for validation against DCAL and to generate improved absorbed dose estimations for diagnostic nuclear medicine using specific absorbed fraction values of the ICRP computational voxel phantoms. The sub-module for absorbed dose calculations in spherical structures 1 mm to 9 cm in diameter and different tissue composition was included to broaden the clinical usefulness of the program. The IDAC-Dose2.1 program is free software for research and available for download at http://www.idac-dose.org.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Real-time single-element-detection structured illumination optical metrology for laser powder bed fusion

Laser powder bed fusion (LPBF) is a type of metal additive manufacturing which could benefit from improved process monitoring to improve quality control. We demonstrate, for the first time to our knowledge, the coaxial monitoring of melt track formation in steel powder with spatial frequency modulation imaging (SPIFI), an enhanced-resolution imaging technique which uses a photodiode to record one-dimensional images. Using a custom live-display software and a high-speed SPIFI geometry, we offset the SPIFI field of view from the fusing beam to monitor different regions of the LPBF melt pool and surrounding area. This demonstrates the potential of SPIFI to monitor spatial features within the melt pool in real-time with increased data efficiency.

Hunter, Scott (ORCID:0009000886150312)↗