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DOE OSTI2023

Autonomous sense and guide machine learning system

A system for generating a machine learning system to generate guidance information based on locations of objects is provided. The system accesses training data that includes training time-of-arrival (“TOA”) information of looks and guidance information for each look. The guidance information is based on a training collection of object locations. The TOA of a look represents, for each object location of a training collection of object locations, times between signals transmitted by transmitters and return signals received by receivers. The return signals represent signals reflected from an object at the object location. The system trains a machine learning system using the training data wherein the machine learning system inputs TOA information and outputs guidance information.

Beer, N. Reginald↗

DOE OSTI2020

Report on Year-2 of Water NSTF Matrix Testing

Under support from the Department of Energy (DOE) and the Office of Advanced Reactor Technologies (ART), a large scale test facility has been constructed at Argonne National Laboratory to generate NQA-1 qualified validation data for passive decay heat removal systems of advanced reactors. The Natural convection Shutdown heat removal Test Facility (NSTF) reflects key features of a ½ scale, water-based, Reactor Cavity Cooling System (RCCS) and is intended to study the behavior, bound performance, and ultimately guide design decisions for passive decay heat removal systems for advanced reactors. Since the facility also retains all aspects common to a fundamental boiling water thermosiphon, the generated experimental data sets are well poised to advance the understanding of fundamental natural circulation boiling and two-phase flow phenomena.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗

DOE OSTI2021

Enriching Load Data Using Micro-PMUs and Smart Meters

In modern distribution systems, load uncertainty can be fully captured by micro-PMUs, which can record high-resolution data; however, in practice, micro-PMUs are installed at limited locations in distribution networks due to budgetary constraints. In contrast, smart meters are widely deployed but can only measure relatively low-resolution energy consumption, which cannot sufficiently reflect the actual instantaneous load volatility within each sampling interval. In this paper, we have proposed a novel approach for enriching load data for service transformers that only have low-resolution smart meters. The key to our approach is to statistically recover the high-resolution load data, which is masked by the low-resolution data, using trained probabilistic models of service transformers that have both high- and low-resolution data sources, i.e., micro-PMUs and smart meters. The overall framework consists of two steps: first, for the transformers with micro-PMUs, a Gaussian Process is leveraged to capture the relationship between the maximum/minimum load and average load within each low-resolution sampling interval of smart meters; a Markov chain model is employed to characterize the transition probability of known high-resolution load. Next, the trained models are used as teachers for the transformers with only smart meters to decompose known low-resolution load data into targeted high-resolution load data. The enriched data can recover instantaneous load uncertainty and significantly enhance distribution system observability and situational awareness. Here, we have verified the proposed approach using real high- and low-resolution load data.

24 POWER TRANSMISSION AND DISTRIBUTION↗

DOE OSTI2025

Chlorophyll- a dynamics in the lower Amazon River: insights from in situ and hyperspectral remote sensing using OCI-PACE

Chlorophyll-a concentration (Chla) is a key indicator of phytoplankton biomass and aquatic trophic status. However, satellite-derived Chla in sediment-rich waters, such as those found in the Lower Amazon River, remains challenging. The present study characterizes in situ Chla levels and their relationships with geographic, physical, and biogeochemical parameters in the Lower Amazon. Data collected between 2014 and 2017 across four hydrological seasons included measurements of Chla, remote sensing reflectance, and water quality parameters such as total suspended sediment, conductivity, water surface temperature, dissolved oxygen, pH, dissolved organic carbon and coloured dissolved organic matter. An empirical model was developed to estimate Chla using simulated hyperspectral bands from NASA’s PACE mission, achieving high performance (R 2 = 0.76; RMSE = 0.11 μg·L −1 ). Red bands proved particularly effective for Chla retrieval, while the addition of ultraviolet bands further enhanced model accuracy. The application of the developed model to satellite imagery yielded results consistent with in situ observations for the same hydrologic season. Seasonal variation and geographic location were major factors influencing Chla dynamics. This study provides a novel contribution to Chla estimation in optically complex, highly turbid waters and highlights the potential of the PACE mission to enhance global aquatic ecosystem monitoring. In conclusion, by offering freely available hyperspectral data with high radiometric resolution, PACE represents a significant advancement in the realm of remote sensing of aquatic environments.

Amazon River↗

DOE OSTI2016

Dimensionally Controlled Lithiation of Chromium Oxide

Oxide conversion reactions are an alternative approach for high capacity lithium ion batteries but are known to suffer from structural irreversibility associated with the phase separation and reconstitution of reduced metal species and Li2O. In particular, the morphology of the reduced metal species is thought to play a critical role in the electrochemical properties of a conversion material. Here we use a model electrode with alternating layers of chromium and chromium oxide to better understand and control these phase changes in real-time and at molecular length scales. Despite lacking crystallinity at the atomic scale, this superstructure is observed (with X-ray reflectivity, XR) to lithiate and delithiate in a purely one-dimensional manner, preserving the layered structure. The XR data show that the metal layers act as nucleation sites for the reduction of chromium in the conversion reaction. Irreversibility during delithiation is due to the formation of a ternary phase, LiCrO2, which can be further delithiated at higher potentials. The results reveal that the combination of confining lithiation to nanoscale sheets of Li2O and the availability of reaction sites in the metal layers in the layered structure is a strategy for improving the reversibility and mass transport properties that can be used in a wide range of conversion materials.

25 ENERGY STORAGE↗

DOE OSTI2018

Overall and cause‐specific mortality in the Sentinel system: A power analysis

Abstract Purpose Mortality data within the Sentinel Death Tables remain generally uncharacterized. Assessment of mortality data within Sentinel will help inform its utility for medical product safety studies. Methods To determine if Sentinel contains sufficient all‐cause and cause‐specific mortality events to power postmarketing safety studies. We calculated crude rates of all‐cause mortality and suicide and proportional mortality from suicide from 2004 to 2012 in seven Sentinel data partners. Results were stratified by data partner, sex, age group, and calendar year and compared with national estimates from Centers for Disease Control and Prevention Wide‐ranging ONline Data for Epidemiologic Research. We performed sample size estimations for all‐cause mortality and 10 leading causes of death. Results We observed 479 694 deaths, including 5811 suicides, during 68 million person‐years of follow‐up. Pooled mean death and suicide rates in the data partners were 710 and 8.6 per 100 000 person‐years, respectively (vs 810 and 11.8 nationally). The mean proportional mortality from suicide among the data partners was 1.2%, compared with 1.5% nationally. National trends of decreasing overall mortality and increasing proportional mortality for suicide were reflected within Sentinel. We estimated that detecting hazard ratios of 1.25 and 3 would require 16 442 and 460 exposed patients, respectively, for overall mortality, and 1.3 million and 37 411, respectively, for suicide. Conclusions This was the first study to investigate mortality data in the Sentinel death tables. We found that all‐cause mortality appeared well powered for use as a safety outcome and cause‐specific mortality outcomes may be adequately powered in certain circumstances. Further investigation into the quality of the Sentinel death data is needed.

Swain, Richard S.↗

DOE OSTI2015

A revised partiality model and post-refinement algorithm for X-ray free-electron laser data

An updated partiality model and post-refinement algorithm for XFEL snapshot diffraction data is presented and confirmed by observing anomalous density for S atoms at an X-ray wavelength of 1.3 Å. Research towards using X-ray free-electron laser (XFEL) data to solve structures using experimental phasing methods such as sulfur single-wavelength anomalous dispersion (SAD) has been hampered by shortcomings in the diffraction models for X-ray diffraction from FELs. Owing to errors in the orientation matrix and overly simple partiality models, researchers have required large numbers of images to converge to reliable estimates for the structure-factor amplitudes, which may not be feasible for all biological systems. Here, data for cytoplasmic polyhedrosis virus type 17 (CPV17) collected at 1.3 Å wavelength at the Linac Coherent Light Source (LCLS) are revisited. A previously published definition of a partiality model for reflections illuminated by self-amplified spontaneous emission (SASE) pulses is built upon, which defines a fraction between 0 and 1 based on the intersection of a reflection with a spread of Ewald spheres modelled by a super-Gaussian wavelength distribution in the X-ray beam. A method of post-refinement to refine the parameters of this model is suggested. This has generated a merged data set with an overall discrepancy (by calculating the R{sub split} value) of 3.15% to 1.46 Å resolution from a 7225-image data set. The atomic numbers of C, N and O atoms in the structure are distinguishable in the electron-density map. There are 13 S atoms within the 237 residues of CPV17, excluding the initial disordered methionine. These only possess 0.42 anomalous scattering electrons each at 1.3 Å wavelength, but the 12 that have single predominant positions are easily detectable in the anomalous difference Fourier map. It is hoped that these improvements will lead towards XFEL experimental phase determination and structure determination by sulfur SAD and will generally increase the utility of the method for difficult cases.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

DOE OSTI2022

Synergistic Retrieval of Temperature and Humidity Profiles from Space-Based and Ground-Based Infrared Sounders Using an Optimal Estimation Method

The atmospheric temperature and humidity profiles of the troposphere are generally measured by radiosondes and satellites, which are essential for analyzing and predicting weather. Nevertheless, the insufficient observation frequencies and low detection accuracy of the boundary layer restricts the description of atmospheric state changes by the temperature and humidity profiles. Therefore, this work focus on retrieving the temperature and humidity profiles using observations of the FengYun-4 (FY-4) Geostationary Interferometric Infrared Sounder (GIIRS) combined with ground-based infrared spectral observations from the Atmospheric Emitted Radiance Interferometer (AERI), which are more accurate than space-based individual retrieval results and have a wider effective retrieval range than ground-based individual retrieval results. Based on the synergistic observations, which are made by matching the space-based and ground-based data with those of different spatial and temporal resolutions, a synergistic retrieval process is proposed to obtain the temperature and humidity profiles at a high frequency under clear-sky conditions based on the optimal estimation method. In this research, using the line-by-line radiative transfer model (LBLRTM) as the forward model for observing simulations, a retrieval experiment was carried out in Qingdao, China, where an AERI is situated. Taking radiosonde data as a reference for comparing the retrieval results of the temperature and humidity profiles of the troposphere, the root-mean-square error (RMSE) of the synergistic retrieval algorithm below 400 hPa is within 2 K for temperature and within 12% for relative humidity. Compared with the GIIRS individual retrieval, the RMSE of temperature and relative humidity for the synergistic method is reduced by 0.13–1.5 K and 2.7–4.4% at 500 hPa, and 0.13–2.1 K and 2.5–7.2% at 900 hPa. Moreover, the forecast index (FI) calculated from the retrieval results shows reasonable consistency with the FIs calculated from the ERA5 reanalysis and from radiosonde data. The synergistic retrieval results have higher temporal resolution than space-based retrieval results and can reflect the changes in the atmospheric state more accurately. Overall, the results demonstrated the promising potential of the synergistic retrieval of temperature and humidity profiles at high accuracy and high temporal resolution under clear-sky conditions from FY-4/GIIRS and AERI.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2019

Quarterly Progress Report Q3 FY2019 Apr-Jun 2019

Our main activity this quarter was focused on carrying out the data analysis following the experimental campaign conducted at the Irradiated Fuel Examination Laboratory (IFEL) at ORNL. More specifically, we focused on the demonstration of hard X-rays two reflections, as well as the quantification of the background reduction and signal-to-noise-ratio (SNR) under different experimental conditions. Significant time and effort was spent developing data analysis tools using the Root software toolkit, and carefully checking data consistency across data sets and with simulations. Some results are presented below.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗

DOE OSTI2022

A Combined Computer Vision and Deep Learning Approach for Rapid Drone-Based Optical Characterization of Parabolic Troughs

Optical accuracy is a primary driver of parabolic trough concentrating solar power (CSP) plant performance, but can be damaged by wind loads, gravity, error during installation, and regular plant operation. Collecting and analyzing optical measurements over an entire operating parabolic trough plant is difficult, given the large scale of typical installations. Distant Observer, a software tool developed at the National Renewable Energy Laboratory, uses images of the absorber tube reflected in the collector mirror to measure both surface slope in the parabolic mirror and offset of the absorber tube from the ideal focal point. This technology has been adapted for fast data collection using low-cost commercial drones, but until recently still required substantial human labor to process large amounts of data. A new method leveraging advanced deep learning and computer vision tools can drastically reduce the time required to process images. This new method addresses the primary analysis bottleneck, identifying featureless, reflective mirror corner points to a high degree of accuracy. Recent work has shown promising results using computer vision methods. The combined deep learning and computer vision approach presented here proved highly effective and has the potential to further automate data collection and analysis, making the tool more robust. The method presented in this paper automatically identified 74.3% of mirror corners within 2 pixels of their manually marked counterparts and 91.9% within 3 pixels. This level of accuracy is sufficient for practical Distant Observer analysis within a target uncertainty. A commercial drone collected video of over 100 parabolic trough modules at an operating CSP plant to demonstrate the deep learning and computer vision method's usefulness in processing large amounts of data. These troughs were successfully analyzed using Distant Observer, paired with the new deep learning and computer vision algorithm, and can provide plant operators and trough designers with valuable insight about plant performance, operating strategies, and plant-wide optical error trends.

computer vision↗

DOE OSTI2019

Growth interactions between icosahedral quasicrystals

We investigate the solidification pathways of a population of icosahedral quasicrystals in a liquid through in situ synchrotron x-ray tomography. The wealth of three-dimensional space- and time-resolved data enables us to test the predictions of various models and theories of crystallization on a quasi-crystal-forming alloy. Remarkably, we find the general evolution equation—that accounts for the competing effects of growth, coalescence, and coarsening—fits well our experimental data on surface area concentration. Furthermore, we quantify the orientation selection, screening length, and coarsening rate of the dodecahedra, and compare these results to that of periodic crystals. The latter is a full order of magnitude smaller than that of elemental metal dendrites in the limit of zero volume fraction, a reflection of the low solid-liquid interfacial energy of the icosahedral phase. Furthermore, our paper provides the critical input data for microstructural models used for integrated computational materials engineering of complex intermetallics, including quasicrystals.

36 MATERIALS SCIENCE↗

DOE OSTI2017

Pd-Ag chronometry of IVA iron meteorites and the crystallization and cooling of a protoplanetary core

To constrain the timescales and processes involved in the crystallization and cooling of protoplanetary cores, we examined the Pd-Ag isotope systematics of the IVA iron meteorites Muonionalusta and Gibeon. A Pd-Ag isochron for Muonionalusta provides an initial 107 Pd/ 108 Pd = (2.57 ± 0.07) × 10 -5 . The three metal samples analyzed from Gibeon plot below the Muonionalusta isochron, but these samples also show significant effects of cosmic ray-induced neutron capture reactions, as is evident from 196 Pt excesses in the Gibeon samples. After correction for neutron capture effects on Ag isotopes, the Gibeon samples plot on the Muonionalusta isochron, indicating that these two IVA irons have indistinguishable initial 107 Pd/ 108 Pd. Collectively, the Pd-Ag data indicate cooling of the IVA core below Pd-Ag closure between 2.9 ± 0.4 Ma and 8.9 ± 0.6 Ma after CAI formation, where this age range reflects uncertainties in the initial 107 Pd/ 108 Pd ratios of the solar system, which in turn result from uncertainties in the Pb-Pb age of Muonionalusta. The Ag isotopic data indicate that the IVA core initially evolved with a modestly elevated Pd/Ag, but the low Ag concentrations measured for some metal samples indicate derivation from a source with much lower Ag contents and, hence, higher Pd/Ag. These contrasting observations can be reconciled if the IVA irons crystallized from an initially more Ag-rich core, followed by extraction of Fe-S melts during compaction of the nearly solidified core. Owing to its strong tendency to partition into Fe-S melts, Ag was removed from the IVA core during compaction, leading to the very low Ag concentration observed in metal samples of IVA irons. Alternatively, Ag was lost by evaporation from a still molten metallic body just prior to the onset of crystallization. The Pd-Ag isotopic data indicate that Muonionalusta cooled at >500 K/Ma through the Pd-Ag closure temperature of ~900 K, consistent with the rapid cooling inferred from metallographic cooling rates for IVA irons. Finally, combined, these observations are consistent with cooling of IVA irons in a metallic body with little or no silicate mantle.

58 GEOSCIENCES↗

DOE OSTI2022

Leaf demography spectra, February 2017, PA-SLZ: Panama

This dataset contains leaf reflectance spectra of sunlit canopy leaves from trees at the San Lorenzo Protected Area (PA-SLZ), Panama. Spectra were measured with a full-spectrum (350 -2500 nm) spectroradiometer with a leaf clip attachment. Leaves previously documented in a demography survey were targeted, and each leaf spectrum is paired with species identification, relative leaf position on each branch and estimated leaf age in days. Leaves were measured from the following species: Apeiba membranacea, Carapa guianensis, Guatteria dumetorum, Miconia borealis, Tachigali versicolor, Terminalia amazonia, Tocoyena pittieri and Vochysia ferruginea Unprocessed spectral data are included as SVC *.sig files, and metadata, including sample details, are presented in *.xlsx files. Leaf reflectance spectra of sunlit canopy leaves from trees at the San Lorenzo Protected Area (PA-SLZ), Panama. Spectra were measured with a full-spectrum (350 -2500 nm) spectroradiometer with a leaf clip attachment. Leaves previously documented in a demography survey were targeted, and each leaf spectrum is paired with species identification, relative leaf position on each branch and estimated leaf age in days. Leaves were measured from the following species: Apeiba membranacea, Carapa guianensis, Guatteria dumetorum, Miconia borealis, Tachigali versicolor, Terminalia amazonia, Tocoyena pittieri and Vochysia ferruginea Unprocessed spectral data are included as SVC *.sig files, and metadata, including sample details, are presented in *.xlsx files.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2018

Comparison of Phenology Estimated from Reflectance-Based Indices and Solar-Induced Chlorophyll Fluorescence (SIF) Observations in a Temperate Forest Using GPP-Based Phenology as the Standard

We assessed the performance of reflectance-based vegetation indices and solar-induced chlorophyll fluorescence (SIF) datasets with various spatial and temporal resolutions in monitoring the Gross Primary Production (GPP)-based phenology in a temperate deciduous forest. The reflectance-based indices include the green chromatic coordinate (GCC), field measured and satellite remotely sensed Normalized Difference Vegetation Index (NDVI); and the SIF datasets include ground-based measurement and satellite-based products. We found that, if negative impacts due to coarse spatial and temporal resolutions are effectively reduced, all these data can serve as good indicators of phenological metrics for spring. However, the autumn phenological metrics derived from all reflectance-based datasets are later than the those derived from ground-based GPP estimates (flux sites). This is because the reflectance-based observations estimate phenology by tracking physiological properties including leaf area index (LAI) and leaf chlorophyll content (Chl), which does not reflect instantaneous changes in phenophase transitions, and thus the estimated fall phenological events may be later than GPP-based phenology. In contrast, we found that SIF has a good potential to track seasonal transition of photosynthetic activities in both spring and fall seasons. The advantage of SIF in estimating the GPP-based phenology lies in its inherent link to photosynthesis activities such that SIF can respond quickly to all factors regulating phenological events. Despite uncertainties in phenological metrics estimated from current spaceborne SIF observations due to their coarse spatial and temporal resolutions, dates in middle spring and autumn—the two most important metrics—can still be reasonably estimated from satellite SIF. Our study reveals that SIF provides a better way to monitor GPP-based phenological metrics.

59 BASIC BIOLOGICAL SCIENCES↗

DOE OSTI2020

Improved Infrared Optical Constants from Pressed Pellets: II. Ellipsometric n and k Values for Ammonium Sulfate with Variability Analysis

Infrared spectral imaging is facilitated via the comparison of spectra recorded in situ to a databank of actual or synthetic infrared reflectance spectra. It has recently been shown that reference spectra corresponding to the many different morphological forms of the same chemical can be generated synthetically using the imaginary, k, and real, n, components of the complex refractive index, n~ = n + ik. One method to obtain the n and k vectors is infrared ellipsometry, which measures the changes in amplitude, tan ?, and phase, ?, of polarized light reflected from the sample both as a function of wavenumber and angle of incidence. The method requires specularly reflected light so best results are usually obtained with polished planar samples of large surface area. Due to the difficulties of obtaining such samples, however, we investigate the possibility of pressing powders of neat materials and obtaining the corresponding optical constants from the pellets. In this paper, variability in the sample pellet and preparation method is investigated, as is variability in the fitting procedure for the derived optical constants. The n/k vectors are derived from the measured ellipsometric parameters, tan ? and ?, as they are fit by an oscillator model which yield n(?) and k(?) vectors as a function of wavenumber, ?. Construction of the oscillator model is not automatic and depends on significant input from the analyst as well as the sample’s physical characteristics. For the pellet pressing, the experimental variability was found to be minimized for size-selected powdered samples as gauged by the minimal variance in ? and ? for three different pellets; similarly, the analytical precision for multiple measurements of the same pellet was also quite good, suggesting that a pressed pellet is a viable sample preparation method. The greatest variability came in the analytic fitting procedure with differences up to 20% arising from four different fits to the same data set. The final ellipsometric n/k data are compared to literature values obtained from crystalline (NH4)2SO4 samples as well as single-angle reflectance measurements that also used pressed pellets. Comparison with the previous literature values shows generally good agreement although higher k-values are observed for the independent sets of data derived from pressed pellets. These data are suggested as an improved set of optical constants for (NH4)2SO4.

optical constants, ellipsometry, ammonium sulfate,↗

DOE OSTI2023

Tunable plasmonic color device and method of making the same

A plasmonic system is disclosed. The system includes at least one polarizer that is configured to provide at least one linearly polarized broadband light beam, an anisotropic plasmonic metasurface (APM) assembly having a plurality of nanoantennae each having a predetermined orientation with respect to a global axis representing encoded digital data, the APM assembly configured to receive the at least one linearly polarized broadband light beam and by applying localized surface plasmon resonance reflect light with selectable wavelengths associated with the predetermined orientations of the nanoantennae, and at least one analyzer that is configured to receive the reflected light with selectable wavelength, wherein the relative angles between each of the at least one analyzers and each of the at least one polarizers are selectable with respect to the global axis, thereby allowing decoding of the digital data.

Kildishev, Alexander V.↗

DOE OSTI2022

Data Validation for Hosting Capacity Analyses [Slides]

The National Renewable Energy Laboratory (NREL), in partnership with the Interstate Renewable Energy Council (IREC), has recently released a report which identifies a suite of best practices for producing trusted, validated hosting capacity analysis results reflecting real-world grid conditions.

24 POWER TRANSMISSION AND DISTRIBUTION↗

DOE OSTI2012

Target Strength of Southern Resident Killer Whales (Orcinus orca): Measurement and Modeling

A major criterion for tidal power licensing in Washington’s Puget Sound is the management of the risk of injury to killer whales due to collision with moving turbine blades. An active monitoring system is being proposed for killer whale detection, tracking, and alerting that links to and triggers temporary turbine shutdown when there is risk of collision. Target strength (TS) modeling of the killer whale is critical to the design and application of any active monitoring system. A 1996 study performed a high-resolution measurement of acoustic reflectivity as a function of frequency of a female bottlenose dolphin (2.2 m length) at broadside aspect and TS as a function of incident angle at 67 kHz frequency. Assuming that killer whales share similar morphology structure with the bottlenose dolphin, we extrapolated the TS of an adult killer whale 7.5 m in length at 67 kHz frequency with -8 dB at broadside aspect and -28 dB at tail side. The backscattering data from three Southern Resident killer whales were analyzed to obtain the TS measurement. These data were collected at Lime Kiln State Park using a split-beam system deployed from a boat. The TS of the killer whale at higher frequency (200 kHz) was estimated based on a three-layer model for plane wave reflection from the lung of the whale. The TS data of killer whales were in good agreement with our model. In this paper, we also discuss and explain possible causes for measurement estimation error.

16 TIDAL AND WAVE POWER↗