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The Scope and Direction of Health Informatics

Health Informatics (HI) is a dynamic discipline based upon the medical sciences, information sciences, and cognitive sciences. Its domain is can broadly be defined as medical information management. The purpose of this paper is to provide an overview of this domain, discuss the current "state of the art" , and indicate the likely growth areas for health informatics. The sources of information utilized in this paper are selected publications from the literature of Health Informatics, HI 5300: Introduction to Health Informatics, which is a course from the Department of Health Informatics at the University of Texas Houston Health Sciences Center, and the author's personal experience in practicing telemedicine and implementing an electronic medical record at the NASA Johnson Space Center. The conclusion is that the direction of Health Informatics is in the direction of data management, transfer, and representation via electronic medical records and the Internet.

McGinnis, Patrick J.↗

Improvement of Aerosol Optical Depth Retrieval over Hong Kong from a Geostationary Meteorological Satellite Using Critical Reflectance with Background Optical Depth Correction

Despite continuous efforts to retrieve aerosol optical depth (AOD) using a conventional 5-channelmeteorological imager in geostationary orbit, the accuracy in urban areas has been poorer than other areas primarily due to complex urban surface properties and mixed aerosol types from different emission sources. The two largest error sources in aerosol retrieval have been aerosol type selection and surface reflectance. In selecting the aerosol type from a single visible channel, the season-dependent aerosol optical properties were adopted from longterm measurements of Aerosol Robotic Network (AERONET) sun-photometers. With the aerosol optical properties obtained fromthe AERONET inversion data, look-up tableswere calculated by using a radiative transfer code: the Second Simulation of the Satellite Signal in the Solar Spectrum (6S). Surface reflectance was estimated using the clear sky composite method, awidely used technique for geostationary retrievals. Over East Asia, the AOD retrieved from the Meteorological Imager showed good agreement, although the values were affected by cloud contamination errors. However, the conventional retrieval of the AOD over Hong Kong was largely underestimated due to the lack of information on the aerosol type and surface properties. To detect spatial and temporal variation of aerosol type over the area, the critical reflectance method, a technique to retrieve single scattering albedo (SSA), was applied. Additionally, the background aerosol effect was corrected to improve the accuracy of the surface reflectance over Hong Kong. The AOD retrieved froma modified algorithmwas compared to the collocated data measured by AERONET in Hong Kong. The comparison showed that the new aerosol type selection using the critical reflectance and the corrected surface reflectance significantly improved the accuracy of AODs in Hong Kong areas,with a correlation coefficient increase from0.65 to 0.76 and a regression line change from τMI [basic algorithm] = 0.41τAERONET + 0.16 to τMI [new algorithm] = 0.70τAERONET + 0.01.

aerosols↗

Ambient monitoring to inform the protection of beneficial uses and achieve water quality goals in Sinclair and Dyes Inlets, Puget Sound, WA

Currently discharge limits enforced under the Clean Water Act are focused on meeting water quality standards at the end of the pipe and environmental performance is measured based on meeting the discharge limits; but meeting discharge limits has very little to do with achieving water quality goals for coastal and estuarine ecosystems. Therefore, an effective monitoring and assessment program is needed to assess continuous process improvement, evaluate the ecological conditions, and provide metrics that can inform effective management of coastal and estuarine water quality. As part of an integrated Environmental Investment (ENVVEST) project for Sinclair and Dyes Inlets (ENVVEST 2006; Johnston et al. 2009) a network of monitoring stations was established to characterize environmental conditions, assess potential impacts, and establish environmental quality trends within the Inlets. Water, sediment, and biota monitoring locations were selected that were co-located near suspected sources (industrial, waste water, and stormwater outfalls; marinas, stream mouths, and other sources) or were representative of ambient marine and nearshore conditions. Water column stations and effluents from industrial outfalls were sampled seasonally for trace metals (Cd, Cr, Cu, Hg, Pb, and Zn) using analytical procedures appropriate for seawater (Strivens, Brandenberger and Johnston, 2018), conventional parameters (salinity, dissolved and total organic carbon, total and suspended solids, dissolved O2, pH, turbidity, NO2+NO3, NH4, N, and P), and toxicity. Effluent and water column toxicity tests included mysid shrimp (Americamysis bahia) 96 hr survival, sand dollar (Dendraster excentricus) or purple sea urchin (Strongylocentrotus purpuratus) 96 hr embryo development, QwikLite – dinoflagellate (Pyrocystis lunula) 24 hr bioluminescence response, mussel larvae (Mytilus sp.) 48 hr larvae survival and development, and kelp (Macrocystis pyrifera) 48 hr growth and germination. Additionally, indigenous mussels (Mytilis spp.) were sampled biennially for contaminant residues of metals, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), lipid content, and stable isotopes of C and N. The mussel data were compared to benchmarks of ecological effects (Johnston et al. 2007, Applied Biomonitoring 2009), samples obtained from a local seafood market harvested from Penn Cove on Whidbey Island (PKPLPC), and data from the national mussel watch status and trends monitoring program (Kimbrough et al. 2008). Results from 2009-2016 showed that dissolved metals nearly always met water quality standards and that water quality in Navy nearshore areas appeared to improve after best management practices (BMPs) for industrial process improvements (US Navy 2012) were completed in Sept. 2013 (Figure 1). In general, toxicity from exposure to whole effluent samples was not observed and ambient water samples were not toxic to test organisms, except that ambient toxicity was only observed during the presence of algal blooms which showed that toxicity was highly correlated with the abundance of the toxic algae Gymnodinium splendens (Rosen et al. 2009). Overall, mussel tissue residues were below benchmarks at most locations (Figure 2), however there were locations that had elevated levels of PAHs, PCBs, Hg, and Cu. Results from the monitoring provide metrics that are being used to assess progress toward meeting environmental quality goals for the watershed.

ENVVEST, PSEMP↗

System and method for in situ volumetric sensing of 3D cure state of resin being used in an additive manufacturing system

An in situ cure monitoring control system for use with a volumetric three dimensional (3D) printing system, wherein the volumetric 3D system includes a container defining a build volume, the container includes a photocurable resist used for making a 3D part, and the resist is responsive to an optical curing beam from a light source, which is controlled by a controller, and which is passed through the resist. The cure monitoring control system includes an optical signal source which generates optical signals having a wavelength selected in relation to a characteristic of the resist, and directed to pass through the build volume. A detector detects the optical signals and generates output signals in accordance therewith. Software monitors the output signals and uses the output signals to modify the curing beam to help optimize curing of the resist.

Panas, Robert Matthew↗

ILLICIT TRANSIT INTERDICTION GLOBAL ANALYSIS

This study aims to enhance the security of radioactive materials during transport by analyzing commonalities in cargo thefts conducted by non-state groups such as thieves and terrorists. This research focuses on identifying patterns and trends in the methods used to steal high-value cargo, with the goal of applying these insights to improve transport security of radioactive materials. Key questions addressed include the frequency of specific tools, techniques, and insider involvement in thefts, as well as the use of weapons, electronic jamming equipment, and specialized tools. Findings will inform security design improvements and industry practices to mitigate vulnerabilities. The study involves a comprehensive review of literature and case studies, utilizing data sources from 2018 to 2023. Articles will be selected based on their relevance to thefts of valuable cargo in transit, with a focus on incidents involving non-state actors. The methodology will include statistical and inferential analysis to identify trends, with results visualized through pie charts, frequency analyses, and terrain maps. The discussion will highlight the implications of findings and provide actionable recommendations for strengthening security measures. Limitations such as data availability and reporting inconsistencies will be acknowledged. Suggestions for future improvements will be constructed using existing case studies and expert feedback. The study’s outcomes aim to raise awareness within the industry, inform policy decisions, and enhance security protocols for radioactive material transport. Metrics for impact include the potential publication of findings, presentations at conferences to raise awareness, and the subsequent actions taken by stakeholders based on the research. By identifying trends and vulnerabilities and suggesting improvements, this research contributes to preventing the illicit use of nuclear and radiological materials.

Zineddin, Dr. Z. [ORNL] (ORCID:0009000848740725)↗

No evidence for radio-quiet BL Lacertae objects

Using a large, flux-limited sample of faint X-ray sources, a search has been conducted for radio-quiet BL Lacertae objects. None has been found. Thirty-two X-ray-selected BL Lac objects and BL Lac candidates have been found within the sources of the Einstein Medium Sensitivity Survey (EMSS). Thirty-one of these have been observed with the VLA and all have been detected at 5 GHz. While the optical magnitudes of the EMSS BL Lac objects range from 17 to 20.8, their radio-to-optical spectral indices occupy a very small range. The very bright X-ray-selected BL Lac objects like PKS 2155-304 and Markarian 501 have similar range values. Therefore, unlike the clear dichotomy between radio-loud quasars and radio-quiet QSOs, there is no evidence for two populations of Lacertids distinguished by radio loudness.

Stocke, John T.↗

Modular Soft X-Ray Emission Spectrograph

We have been developing the Hettrick-Underwood type soft x-ray spectrograph for over a decade. This optical design uses one spherical mirror for focusing x-rays onto the CCD detector and a set of variable line-spacing gratings for energy analysis. Unlike the previous effort carried out at the ALS, what we have achieved in the current design is to incorporate the concept of modularity. The model of spectrograph is shown below. It contains three major components: the optics chamber and downstream section (detector plus driving mechanism using a swing arm pivoted at the grating location, see figure) for inside and outside order (translation stage without swing arm, not shown here). Inside order design is often used when source size is larger than the detector pixel resolution, while the outside order is used when source size is smaller than the detector pixel resolution. Irrespective to which order is selected, there is no change in the mechanism of optics chamber. The location of optics chamber relative to the source and detector can also be changed to optimize the energy resolution at target photon energy. The incident angles on mirror and gratings can be varied, in conjunction with the grating line densities, to balance the resolution and throughput. The internal components of optics chamber are also modular and changing the dimension of optics can be done by using different holders. The modularity not only greatly reduces the design and assembling effort, but also offers the cost benefit. Although the cost of this type of spectrograph is expected to be higher than XES350, it is still significant lower than the one-of-the-kind design used at every synchrotron facilities. The unique flexibility and modularity not only allows the users to tailor the design of spectrograph for the characteristic of their sources, but also to have cost down in standardizing the fabrication parts.

Hussain, Zahid↗

Kinetic Monte Carlo Simulations of Chemical Reactions on Surfaces

Lattice based kinetic Monte Carlo (kMC) simulations are a powerful tool for micro-kinetic modeling. The kinetic Monte Carlo technique stochastically simulates chemical reaction processes (e.g. adsorption, desorption, diffusion), where the probability of a given reaction process being selected is weighted by its rate constant. The open source software package, KMOS1, allows fast construction of kMC simulations by automatically implementing a computationally efficient kMC framework, thus allowing the researcher to focus on accurate parameterization and formulation of the kinetic model. From this, the spatiotemporal evolution (e.g. concentration, surface configuration, turnover frequencies) of crystal surfaces or bulk crystalline structures is obtained. KMOS uses the variable step-size method implementation of kMC. At each step, the VSSM updates available events, calculates the corresponding transition rates and simulation time, and selects one of the available events. The lattice based kMC technique has many potential applications within SRNL where chemical kinetics are of interest. By transitioning through time along a trajectory of configuration space, fundamental insights to a system's dominant reactions and parameters can be gained, leading to improved materials and process design. In this work, we have established capabilities for fast implementation of kMC simulations through the installation and testing of the KMOS software on SRNL high performance computing resources. The parameterization of kMC simulations is often performed from first-principles energetic calculations. For the purposes of this work, the test cases use arbitrary species and thus, have arbitrary parameterization. In order to demonstrate the use of KMOS, two primary test cases are shown. Case 1 involves simple adsorption and desorption. Case 2 involves a slightly more complex mechanism. The evolution of the surface concentration and the final surface configuration for simulation Case 2 is shown. Rate-limiting processes and rate-limiting configurations are not always known or understood, but kMC provides information pertaining to both. The capability to implement efficient micro-kinetic models using the kinetic Monte Carlo technique has been established through the testing and installation of KMOS on SRNL HPC resources.

97 MATHEMATICS AND COMPUTING↗

A Vacuum-Compatible, Spectrally Tunable, Flat Panel Uniform Source for Testing Large Aperture Earth Observation Systems

Labsphere, Inc in conjunction with NASA GSFC and Genesis Engineering Solutions inc. has developed an innovative, fully T-VAC compatible, calibration spectro-radiometric illumination source with a highly uniform large-area rectangular flat panel active area. This source leverages a new shaped integration geometry to achieve high uniformity over a large active output area while maintaining a smaller and more robust overall form-factor when compared to previous designs or integrating spheres. This new illuminator also leverages a set of selectable LED arrays as well as broadband tungsten-halogen sources to provide multi-level, wide spectrum reference illumination to the VIIRS instrument over all optical sensor bands during pre-launch testing. The first unit has been demonstrated to meet its requirements using ambient technology and a fully-vacuum-compatible second unit is planned to allow testing for T-VAC campaigns. This technology is both flexible and capable of meeting the needs of many other instruments/missions requiring this type of test/calibration capability.

Jeff Holt↗

Broadband polarization-entangled source for C+L-band flex-grid quantum networks

The rising demand for transmission capacity in optical networks has motivated steady interest in expansion beyond the standard C-band (1530–1565 nm) into the adjacent L-band (1565–1625 nm) for an approximate doubling of capacity in a single stroke. However, in the context of quantum networking, the L-band has yet to be fully leveraged with the suite of advanced tools for characterization and management available from classical lightwave communications. In this work, we demonstrate an ultrabroadband two-photon source integrating both C- and L-band wavelength-selective switches for complete control of spectral routing and allocation across 7.5 THz in a single setup. Polarization state tomography of all 150 pairs of 25-GHz-wide channels reveals an average fidelity of 0.98 and total distillable entanglement greater than 181 kebits/s. This source is explicitly designed for flex-grid optical networks and can facilitate optimal utilization of entanglement resources across the full C+L-band.

42 ENGINEERING↗

Searching for Compact Radio Sources Associated with UCH ii Regions

Ultra-compact (UC)H ii regions represent a very early stage of massive star formation. The structure and evolution of these regions are not yet fully understood. Interferometric observations showed in recent years that compact sources of uncertain nature are associated with some UCH ii regions. To examine this, we carried out VLA 1.3 cm observations in the A configuration of selected UCH ii regions in order to report additional cases of compact sources embedded in UCH ii regions. With these observations, we find 13 compact sources that are associated with 9 UCH ii regions. Although we cannot establish an unambiguous nature for the newly detected sources, we assess some of their observational properties. According to the results, we can distinguish between two types of compact sources. One type corresponds to sources that are probably deeply embedded in the dense ionized gas of the UCH ii region. These sources are photoevaporated by the exciting star of the region and will last for 10{sup 4}–10{sup 5} years. They may play a crucial role in the evolution of the UCH ii region as the photoevaporated material could replenish the expanding plasma and might provide a solution to the so-called lifetime problem of these regions. The second type of compact sources is not associated with the densest ionized gas of the region. A few of these sources appear resolved and may be photoevaporating objects such as those of the first type, but with significantly lower mass depletion rates. The remaining sources of this second type appear unresolved, and their properties are varied. We speculate on the similarity between the sources of the second type and those of the Orion population of radio sources.

79 ASTRONOMY AND ASTROPHYSICS↗

Fabrication and Modeling of High-Efficiency Front Junction N-Type Silicon Solar Cells With Tunnel Oxide Passivating Back Contact

This paper reports on in-depth understanding, modeling, and fabrication of 23.8% efficient 4 cm 2 n-type Float Zone (FZ) silicon cells with a selective boron emitter and photolithography contact on front and tunnel oxide passivating contact on the back. Tunnel oxide passivating contact composed of a very thin chemically grown silicon oxide (~15 Å) capped with plasma-enhanced chemical vapor deposition (PECVD) grown 20 nm n + poly Si gave excellent surface passivation and carrier selectivity with very low saturation current density (~5 fA/cm 2 ). A high-quality boron selective emitter was formed using ion implantation and solid source diffusion to minimize metal recombination and emitter saturation current density. Process optimization resulted in a cell V oc of 712 mV, J sc of 41.2 mA/cm 2 , and FF of 0.811. Here, a simple methodology is used to model these cells which replaces tunnel oxide passivating contact region by electron and hole recombination velocities extracted from measured saturation current density of tunnel oxide passivating contact region and analysis. Using this approach and two-dimensional device modeling gave an excellent match between the measured and simulated cell parameters and efficiency, supporting excellent passivation and carrier selectivity of these contacts. Extended simulations showed that 26% cell efficiency can be achieved with this cell structure by further optimization of wafer quality, emitter profile, and contact design

14 SOLAR ENERGY↗

Realtime mitigation of GPS SA errors using Loran-C

The hybrid use of Loran-C with the Global Positioning System (GPS) was shown capable of providing a sole-means of enroute air radionavigation. By allowing pilots to fly direct to their destinations, use of this system is resulting in significant time savings and therefore fuel savings as well. However, a major error source limiting the accuracy of GPS is the intentional degradation of the GPS signal known as Selective Availability (SA). SA-induced position errors are highly correlated and far exceed all other error sources (horizontal position error: 100 meters, 95 percent). Realtime mitigation of SA errors from the position solution is highly desirable. How that can be achieved is discussed. The stability of Loran-C signals is exploited to reduce SA errors. The theory behind this technique is discussed and results using bench and flight data are given.

Braasch, Soo Y.↗

An open-source framework for balancing computational speed and fidelity in production cost models

Studies of bulk power system operations need to incorporate uncertainty and sensitivity analyses, especially around exposure to weather and climate variability and extremes, but this remains a computational modeling challenge. Commercial production cost models (PCMs) have shorter runtimes, but also important limitations (opacity, license restrictions) that do not fully support stochastic simulation. Open-source PCMs represent a potential solution. They allow for multiple, simultaneous runs in high-performance computing environments and offer flexibility in model parameterization. Yet, developers must balance computational speed (i.e. runtime) with model fidelity (i.e. accuracy). In this paper, we present Grid Operations (GO), a framework for instantiating open-source, scale-adaptive PCMs. GO allows users to search across parameter spaces to identify model versions that appropriately balance computational speed and fidelity based on experimental needs and resource limits. Results provide generalizable insights on how to navigate the fidelity and computational speed tradeoff through parameter selection. We show that models with coarser network topologies can accurately mimic market operations, sometimes better than higher-resolution models. It is thus possible to conduct large simulation experiments that characterize operational risks related to climate and weather extremes while maintaining sufficient model accuracy.

42 ENGINEERING↗

Optimizing cone beam CT scatter estimation in egs-cbct for a clinical and virtual chest phantom

Purpose: Cone beam computed tomography (CBCT) image quality suffers from contamination from scattered photons in the projection images. Monte Carlo simulations are a powerful tool to investigate the properties of scattered photons.egs-cbct, a recent EGSnrc user code, provides the ability of performing fast scatter calculations in CBCT projection images. This paper investigates how optimization of user inputs can provide the most efficient scatter calculations. Methods: Two simulation geometries with two different x-ray sources were simulated, while the user input parameters for the efficiency improving techniques (EITs) implemented inegs-cbct were varied. Simulation efficiencies were compared to analog simulations performed without using any EITs. Resulting scatter distributions were confirmed unbiased against the analog simulations. Results: The optimal EIT parameter selection depends on the simulation geometry and x-ray source. Forced detection improved the scatter calculation efficiency by 80%. Delta transport improved calculation efficiency by a further 34%, while particle splitting combined with Russian roulette improved the efficiency by a factor of 45 or more. Combining these variance reduction techniques with a built-in denoising algorithm, efficiency improvements of 4 orders of magnitude were achieved. Conclusions: Using the built-in EITs inegs-cbct can improve scatter calculation efficiencies by more than 4 orders of magnitude. To achieve this, the user must optimize the input parameters to the specific simulation geometry. Realizing the full potential of the denoising algorithm requires keeping the statistical uncertainty below a threshold value above which the efficiency drops exponentially.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

The search for transient astrophysical neutrino emission with IceCube-DeepCore

We present the results of a search for astrophysical sources of brief transient neutrino emission using IceCube and DeepCore data acquired between 2012 May 15 and 2013 April 30. While the search methods employed in this analysis are similar to those used in previous IceCube point source searches, the data set being examined consists of a sample of predominantly sub-TeV muon-neutrinos from the Northern Sky (−5{sup ∘}<δ<90{sup ∘}) obtained through a novel event selection method. This search represents a first attempt by IceCube to identify astrophysical neutrino sources in this relatively unexplored energy range. The reconstructed direction and time of arrival of neutrino events are used to search for any significant self-correlation in the data set. The data revealed no significant source of transient neutrino emission. This result has been used to construct limits at timescales ranging from roughly 1 s to 10 days for generic soft-spectra transients. We also present limits on a specific model of neutrino emission from soft jets in core-collapse supernovae.

79 ASTRONOMY AND ASTROPHYSICS↗

Satellite-based interference analyzer

System identifies terrestrial sources of radiofrequency interference and measures their frequency spectra and amplitudes. Designed to protect satellite communication networks, system measures entire noise spectrum over selected frequency band and can raster-scan geographical region to locate noise sources. Once interference is analyzed, realistic interference protection ratios are determined and mathematical models for predicting ratio-frequency noise spectra are established. This enhances signal-detection and locates optimum geographical positions and frequency bands for communication equipment.

Varice, H.↗

Development of Experimental and Computational Aeroacoustic Tools for Advanced Liner Evaluation

Acoustic liners in aircraft engine nacelles suppress radiated noise. Therefore, as air travel increases, increasingly sophisticated tools are needed to maximize noise suppression. During the last 30 years, NASA has invested significant effort in development of experimental and computational acoustic liner evaluation tools. The Curved Duct Test Rig is a 152-mm by 381- mm curved duct that supports liner evaluation at Mach numbers up to 0.3 and source SPLs up to 140 dB, in the presence of user-selected modes. The Grazing Flow Impedance Tube is a 51- mm by 63-mm duct currently being fabricated to operate at Mach numbers up to 0.6 with source SPLs up to at least 140 dB, and will replace the existing 51-mm by 51-mm duct. Together, these test rigs allow evaluation of advanced acoustic liners over a range of conditions representative of those observed in aircraft engine nacelles. Data acquired with these test ducts are processed using three aeroacoustic propagation codes. Two are based on finite element solutions to convected Helmholtz and linearized Euler equations. The third is based on a parabolic approximation to the convected Helmholtz equation. The current status of these computational tools and their associated usage with the Langley test rigs is provided.

Jones, Michael G.↗