Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “Persistent Identifiers”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,045 records · Page 58

A Climatology and Life‐Cycle Characteristics of Atmospheric Fronts and Their Associated Precipitation

Abstract Atmospheric fronts are one of the main sources of mid‐latitude variability. We employ a novel method for identifying and tracking fronts and frontal precipitation. Thermal and dynamical variables are used to identify fronts as areal objects in space, which are tracked in time using the open‐source TempestExtremes software package. Precipitation objects are co‐located to identify frontal precipitation. The method is subjected to validation and sensitivity tests using manually curated data from the National Weather Service. Climatologies of fronts and frontal precipitation are computed from reanalysis and observations; fronts are present upwards of 14% of the time in the storm tracks, and represent the majority (up to 90%) of total and extreme precipitation. Novel aspects of the method are showcased through the lifetime characteristics of fronts across North America. Three sets of warm and cold fronts were discovered, and their duration, distance‐traveled, and translation velocity are examined. Plain Language Summary Mid‐latitude low‐pressure systems and weather fronts are important for our day‐to‐day experience of weather events, particularly in the mid‐latitudes. This work makes use of standardized atmospheric data and creates a method of automatically tracking these important atmospheric features and their precipitation to quantify their relative role in global precipitation. Weather fronts are persistent in the mid‐latitudes and are associated with the majority of precipitation–particularly the most intense precipitation. Trajectories of fronts over North America are categorized to create a set of archetypal fronts that occur in that region. The differences between these types of fronts are characterized. Key Points An automated, efficient, and skillful frontal detection algorithm is developed and validated Fronts contribute a larger fraction of extreme precipitation than all precipitation in mid‐latitude storm tracks Fronts across North America have substantial variation in characteristics depending on their origin location

extratropical cyclone↗

Battery Data MI Importer Template Quick Start Guide

In order to ensure the persistent availability and reliability of test data generated over the course of the project, the M-SHELLS Project has decided to store acquired test data, as well as associated pedigree information, in the Granta Materials Intelligence (MI) database. To facilitate that effort, an importer template and associated graphical user interface (GUI) software have been developed, with this guide providing the operating instructions for their use. The template and automation software GUI are contained in the BatteryDataImporter.xlsm Excel workbook, and are to be used to import M-SHELLS summary, or pedigree, data and the associated raw test data results into an importer template-based file, formatted in such a way as to be ready for immediate upload to the Test Data: Battery Performance table of the Granta MI database. The provided GUI enables the user to select the appropriate summary data file(s), with each file containing the required information to identify any associated raw test data file(s) to be processed. In addition to describing the setup and operation of the importer template and GUI software, this guide also provides instructions for uploading processed data to the database and for viewing the data following upload.

Levinson, Laurie H.↗

Historical trends and extremes in boreal Alaska river basins

Climate change will shift the frequency, intensity, duration and persistence of extreme hydroclimate events and have particularly disastrous consequences in vulnerable systems such as the warm permafrost-dominated Interior region of boreal Alaska. This work focuses on recent research results from nonparametric trends and nonstationary generalized extreme value (GEV) analyses at eight Interior Alaskan river basins for the past 50/60 years (1954/64–2013). Trends analysis of maximum and minimum streamflow indicates a strong (>+50%) and statistically significant increase in 11-day flow events during the late fall/winter and during the snowmelt period (late April/mid-May), followed by a significant decrease in the 11-day flow events during the post-snowmelt period (late May and into the summer). The April–May–June seasonal trends show significant decreases in maximum streamflow for snowmelt dominated systems (<–50%) and glacially influenced basins (–24% to –33%). Annual maximum streamflow trends indicate that most systems are experiencing declines, while minimum flow trends are largely increasing. Nonstationary GEV analysis identifies time-dependent changes in the distribution of spring extremes for snowmelt dominated and glacially dominated systems. Temperature in spring influences the glacial and high elevation snowmelt systems and winter precipitation drives changes in the snowmelt dominated basins. The Pacific Decadal Oscillation was associated with changes occurring in snowmelt dominated systems, and the Arctic Oscillation was linked to one lake dominated basin, with half of the basins exhibiting no change in response to climate variability. The paper indicates that broad scale studies examining trend and direction of change should employ multiple methods across various scales and consider regime dependent shifts to identify and understand changes in extreme streamflow within boreal forested watersheds of Alaska.

54 ENVIRONMENTAL SCIENCES↗

Possible Demonstration of a Polaronic Bose-Einstein(-Mott) Condensate in UO 2(+x) by Ultrafast THz Spectroscopy and Microwave Dissipation

Bose-Einstein condensates (BECs) composed of polarons would be an advance because they would combine coherently charge, spin, and a crystal lattice. Following our earlier report of unique structural and spectroscopic properties, we now identify potentially definitive evidence for polaronic BECs in photo- and chemically doped UO 2(+x) on the basis of exceptional coherence in the ultrafast time dependent terahertz absorption and microwave spectroscopy results that show collective behavior including dissipation patterns whose precedents are condensate vortex and defect disorder and condensate excitations. Furthermore, that some of these signatures of coherence in an atom-based system extend to ambient temperature suggests a novel mechanism that could be a synchronized, dynamical, disproportionation excitation, possibly via the solid state analog of a Feshbach resonance that promotes the coherence. Such a mechanism would demonstrate that the use of ultra-low temperatures to establish the BEC energy distribution is a convenience rather than a necessity, with the actual requirement for the particles being in the same state that is not necessarily the ground state attainable by other means. Interestingly, a macroscopic quantum object created by chemical doping that can persist to ambient temperature and resides in a bulk solid would be revolutionary in a number of scientific and technological fields.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

Persistent minimal sequences of SARS-CoV-2

Abstract Motivation Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused more than 14 million cases and more than half million deaths. Given the absence of implemented therapies, new analysis, diagnosis and therapeutics are of great importance. Results Analysis of SARS-CoV-2 genomes from the current outbreak reveals the presence of short persistent DNA/RNA sequences that are absent from the human genome and transcriptome (PmRAWs). For the PmRAWs with length 12, only four exist at the same location in all SARS-CoV-2. At the gene level, we found one PmRAW of size 13 at the Spike glycoprotein coding sequence. This protein is fundamental for binding in human ACE2 and further use as an entry receptor to invade target cells. Applying protein structural prediction, we localized this PmRAW at the surface of the Spike protein, providing a potential targeted vector for diagnostics and therapeutics. In addition, we show a new pattern of relative absent words (RAWs), characterized by the progressive increase of GC content (Guanine and Cytosine) according to the decrease of RAWs length, contrarily to the virus and host genome distributions. New analysis shows the same property during the Ebola virus outbreak. At a computational level, we improved the alignment-free method to identify pathogen-specific signatures in balance with GC measures and removed previous size limitations. Availability and implementation https://github.com/cobilab/eagle. Supplementary information Supplementary data are available at Bioinformatics online.

Pratas, Diogo↗

Including health in environmental impact assessments of three mega transport projects in Sydney, Australia: A critical, institutional, analysis

This article details how health impacts came to be assessed in three mega, billion dollar, transport infrastructure projects, two road tunnels and one light rail, in Sydney Australia. The known health impacts of transport decisions include environmental, behavioural and social factors. EIA practice prioritises environmental risks, and there has been scant attention to understanding why this is persistently the case. Here we provide a critical theory lens, using critical realist methodology, to analyse empirical data collected through interviews and documents for the three cases. Our analysis focusses on EIA practice within its institutional context, building on ‘new institutional’ approaches to policy analysis that emphasise actors (the stakeholders involved in the EIA), structures (the ‘rules of the game’ that influence practice in systems), and power. We find that the various actors engaged in the EIAs principally to address particular goals that were pre-determined by the system in which they worked or belonged. Structurally, each EIA was undertaken as a compliance process relatively late in the planning process. Considering project options was not part of the EIA's purpose. Resources to undertake the EIAs were provided by those funding the projects (“the proponents”) and determined the types of issues to be considered. The full range of links between transport and health were not identified. Concerning power, health impacts were considered through inter-professional technical negotiation. The inability to engage in the fundamental options driving projects meant impacted communities questioned the validity of the EIA, and the health assessment within this. Our institutional analysis provides important knowledge about how the EIAs preferenced a focus on specific health risks to the detriment of the known broader determinants that shape the health impacts of transport.

54 ENVIRONMENTAL SCIENCES↗

Indium–Poly(carboxylic acid) Ligand Interactions Modify InP Quantum Dot Nucleation and Growth

Size control through precursor reactivity in InP quantum dot (QD) synthesis has been difficult due to the presence of kinetically persistent InP clusters when using conventional indium carboxylate and tris(trimethylsilyl)phosphine chemistry. However, the advent of indium halide/aminophosphine-based synthesis creates new opportunities to harness precursor design to impact nucleation and growth. Driven to further explore indium coordination as a synthetic handle in InP QD synthesis, we examined the effect of a strongly chelating anion on the nucleation and growth of InP QDs. Increasing the equivalents of metal-chelating aminopoly(carboxylic acid) EDTA ([CH 2 N(CH 2 CO 2 H) 2 ] 2 ) (0–0.75 equiv per indium) is found to decrease the final diameter of InP QDs from 4.5 to 2.3 nm by lowering the initial InP growth rate. This size trend is rationalized by invoking a continuous nucleation model. Control experiments carried out with substoichiometric equivalents of indium do not exhibit a drastic size decrease, pointing to complex effects of EDTA on the indium precursor reactivity. By 1 H NMR spectroscopy, EDTA is identified to form an octahedral complex with indium that is less reactive. Furthermore, this competitive decrease in reactivity and in the effective concentration of indium precursor is proposed to suppress the initial InP growth rates and consequently decrease the final size of the nanocrystals.

36 MATERIALS SCIENCE↗

Transient Three-Dimensional Analysis of Side Load in Liquid Rocket Engine Nozzles

Three-dimensional numerical investigations on the nozzle start-up side load physics were performed. The objective of this study is to identify the three-dimensional side load physics and to compute the associated aerodynamic side load using an anchored computational methodology. The computational methodology is based on an unstructured-grid, and pressure-based computational fluid dynamics formulation, and a simulated inlet condition based on a system calculation. Finite-rate chemistry was used throughout the study so that combustion effect is always included, and the effect of wall cooling on side load physics is studied. The side load physics captured include the afterburning wave, transition from free- shock to restricted-shock separation, and lip Lambda shock oscillation. With the adiabatic nozzle, free-shock separation reappears after the transition from free-shock separation to restricted-shock separation, and the subsequent flow pattern of the simultaneous free-shock and restricted-shock separations creates a very asymmetric Mach disk flow. With the cooled nozzle, the more symmetric restricted-shock separation persisted throughout the start-up transient after the transition, leading to an overall lower side load than that of the adiabatic nozzle. The tepee structures corresponding to the maximum side load were addressed.

Wang, Ten-See↗

Unlocking the Potential of Marine Energy Using Hydrogen Generation Technologies

Marine energy, including ocean waves, ocean currents, ocean thermal gradients, tides, and river currents, is a vast and untapped resource that can be harnessed to help enable the transition to renewable energy. Marine energy is an attractive renewable resource because of its energy density, predictability, and persistence. Further, marine energy has the potential to provide energy for utility-scale applications, remote and distributed applications, and rapidly expanding maritime industries, such as aquaculture and shipping. Marine energy technologies are, however, at a nascent stage of development, and a significant amount of the resource is located far from population centers and transmission infrastructure. Accordingly, to unlock the full potential of marine energy, efficient methods of storing and transporting captured marine energy are needed so that the energy can be used when and where it is needed. A promising solution to these energy storage and transportation challenges is to combine marine energy and hydrogen generation technologies. Herein, we provide a high-level analysis of the unique value proposition and technical challenges of combining marine energy and hydrogen technologies. First, we review marine energy technologies, electrolysis technologies, and hydrogen storage methods. Next, we consider specific applications and opportunities for combining the two technologies. Finally, we identify critical R&D challenges that must be overcome to successfully combine marine energy and hydrogen generation technologies. As part of our fact-finding effort in this area, we held a workshop attended by marine energy and hydrogen technology experts from industry, academia, national labs, and government entities to explore the technical challenges and opportunities for combined marine energy and hydrogen generation systems. Our intent is that this document and the report from the workshop can be used in conjunction to help identify and direct research and development that is needed to realize the potential of marine energy-hydrogen systems.

08 HYDROGEN↗

Emergence of the Persistent Spin Helix in Semiconductor Quantum Wells

According to Noether's theorem, for every symmetry in nature there is a corresponding conservation law. For example, invariance with respect to spatial translation corresponds to conservation of momentum. In another well-known example, invariance with respect to rotation of the electron's spin, or SU(2) symmetry, leads to conservation of spin polarization. For electrons in a solid, this symmetry is ordinarily broken by spin-orbit (SO) coupling, allowing spin angular momentum to flow to orbital angular momentum. However, it has recently been predicted that SU(2) can be recovered in a two-dimensional electron gas (2DEG), despite the presence of SO coupling. The corresponding conserved quantities include the amplitude and phase of a helical spin density wave termed the 'persistent spin helix' (PSH). SU(2) is restored, in principle, when the strength of two dominant SO interactions, the Rashba ({alpha}) and linear Dresselhaus ({beta}{sub 1}), are equal. This symmetry is predicted to be robust against all forms of spin-independent scattering, including electron-electron interactions, but is broken by the cubic Dresselhaus term ({beta}{sub 3}) and spin-dependent scattering. When these terms are negligible, the distance over which spin information can propagate is predicted to diverge as {alpha} {yields} {beta}{sub 1}. Here we observe experimentally the emergence of the PSH in GaAs quantum wells (QW's) by independently tuning {alpha} and {beta}{sub 1}. Using transient spin-grating spectroscopy (TSG), we find a spin-lifetime enhancement of two orders of magnitude near the symmetry point. Excellent quantitative agreement with theory across a wide range of sample parameters allows us to obtain an absolute measure of all relevant SO terms, identifying {beta}{sub 3} as the main SU(2) violating term in our samples. The tunable suppression of spin-relaxation demonstrated in this work is well-suited for application to spintronics.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Is a Prescribed Fire Sufficient to Slow the Spread of Woody Plants in an Infrequently Burned Grassland? A Case Study in Tallgrass Prairie

In many mesic grasslands, such as the central Great Plains in North America, frequent fire is a key regulator of ecological processes. Long periods of infrequent fire facilitate the conversion of herbaceous-dominated grassland to woody-dominated shrubland or woodland. At the Konza Prairie Biological Station in northeast Kansas, one infrequently burned portion of the landscape has undergone transformation from grassland to woodland after nearly 30 yr without fire. In Spring 2017, a prescribed burn was implemented to assess fire effectiveness on woody plant mortality. A postfire census of 3 000+ individual woody plants identified the distribution of species by size (height), topographic position, and slope on the landscape. Mortality and canopy fire damage were calculated for each individual. In lowland locations with near-continuous shrub cover (30.7% of the landscape), woody plants were unaffected by fire. However, in upland and slope locations, where shrubs and trees were sparser, survival probability varied by topographic position and species. In these locations 68% of all woody individuals experienced 90% or greater fire damage to the canopy, with 56% of these individuals exhibiting new canopy regrowth within 2 mo after the fire. Here, the two most abundant woody shrubs, Cornus drummondii and Rhus aromatica, showed high survival at all height classes and landscape positions. The two abundant tree species, Gleditsia triacanthos and Juniperus virginiana, showed increased survival probability with tree height that varied by landscape position. Survival of J. virginiana also varied according to proximity and size of neighboring clonal shrubs, providing a mechanism for persistence of this fire-sensitive tree species even at small height classes. The probability survival curves developed here are useful for managers assessing when to prescribe fire to maximize mortality for J. virginiana and provide insight relevant for broader ecological understanding of woody encroachment within grasslands throughout the world.

54 ENVIRONMENTAL SCIENCES↗

A Comprehensive Method to Mitigate Forced Oscillations in Large Interconnected Power Grids

Multiple severe forced oscillation events have recently been observed across the North American interconnections and around the world. These forced oscillations have caused power swings, limited power transfer capability, damaged equipment, and persisted indefinitely until the driving source was located and removed. This paper proposes a comprehensive method to mitigate forced oscillations. Once a forced oscillation is detected, a new source location algorithm can be used to locate the source based on the oscillation mode angle without requiring system topology information. If the source cannot be quickly located and removed, a control strategy can be activated to modulate the active power of utility-scale inverterbased battery energy storage systems (BESSs) to reduce the energy of forced oscillations to a safe level and allow sufficient time for locating the exact source. The proposed source location algorithm is validated using measurements collected during the January 11, 2019 forced oscillation event in North America and other actual grid events, while the proposed control strategy is verified using the Eastern Interconnection dynamic model under the replicated January 11, 2019 forced oscillation event. The simulation results demonstrated that the proposed source location algorithm can accurately identify the forced oscillation source, and the proposed control strategy can significantly reduce forced oscillation energy.

24 POWER TRANSMISSION AND DISTRIBUTION↗

Remediation Guidance for Major Airports after a Bioterrorist Attack

This document provides general guidelines for airport managers, local officials, and other stakeholders for developing a response and recovery plan for a major airport following the release of a biological warfare agent, with specific guidance for remediation. San Francisco International Airport was selected as the example airport during development of the guidance to illustrate specific details. The spore-forming bacterium Bacillus anthracis was selected as the biological agent of primary concern because it is the most difficult of known bioterrorism agents to inactivate and is considered to be one of the agents most likely to be used as a biological weapon. The focus of the guidance is on cleanup and disposal activities associated with the Characterization, Decontamination, and Clearance Phases that are defined herein. Activities associated with the Notification and First-Response Phases are brieÀy discussed in Appendixes A and B, respectively. In addition to the main text of this Remediation Guidance document and associated appendixes, a data supplement was developed specifically for San Francisco International Airport. Requests for the data supplement must be made directly to the Emergency Planning Operations Division of San Francisco International Airport. This document does not describe public health responses to release of a biological warfare agent. If laboratory analytical results confirm the presence of a biological agent, the responsible public health agency involved in the response will commence appropriate public health actions, such as treatment (CDC 2004) and decontamination of potentially contaminated individuals, distribution of prophylaxis, and medical examinations. See the Centers for Disease Control and Prevention web site for more information on emergency public health responses (http://www.bt.cdc.gov/). Effective communication with the media and the public is an essential component of airport remediation and recovery. Whereas such communication is beyond the scope of this document, many helpful resources are available. (See Section 1.1 for more information.) The concept of operations described in this document for cleanup of a Bacillus anthracis release at a major airport conforms to the National Response Framework (NRF) (DHS 2008) and implementation of the National Incident Management System (NIMS 2004). In most cases, a Unified Command would be formed to direct the cleanup process jointly and to take ultimate responsibility for all cleanup decisions. The Unified Command would likely include the Airport Manager or Airport Emergency Operations Manager, representatives from state and local public health and emergency management agencies, and Federal agencies, such as the U.S. Environmental Protection Agency. The Unified Command and Incident Command Staff would ideally be co-located in an Incident Command Post in an uncontaminated area of the airport. If a release is large or complex, co-location of all key players may not be possible. If a major incident is declared, a Principal Federal Official may be appointed by the Department of Homeland Security to facilitate Federal support to the Unified Command. In some facilities and jurisdictions, additional response plans or procedures (such as BioWatch or other emergency response plans, procedures, or protocols) may govern notification and first response. Facility personnel, responders, and emergency management coordinators should be aware of all applicable plans and procedures and how to implement them. Cleanups following the anthrax attacks of 2001 in the U.S. pre-dated the NRF and NIMS and did not make use of a NIMS Incident Command System as we know it today. Most Incident Commanders for the larger of those cleanups chose to convene a Technical Working Group (TWG) of multi-agency, multi-disciplinary, outside experts to advise in developing sampling and decontamination plans. Most of the Incident Commanders also convened a separate Environmental Clearance Committee (ECC) to independently review pre- and post decontamination sampling data as well as data on decontamination parameters, to evaluate whether the decontamination was effective, and to add credibility regarding a decision that decontaminated areas may be reoccupied. Use of such specialized technical expertise is strongly recommended, although it would now operate within the construct of the NIMS Incident Command System. The TWG, if convened, would act in an advisory capacity to the Environmental Unit within the Planning Section. Likewise, the ECC, if convened, would provide independent peer review of products and recommendations by the Environmental Unit. For maximum impartiality, the ECC could also provide recommendations directly to the Unified Command. Cleanup activities commence with site characterization. The principal goal of characterization is to define the extent of contamination and to gather information needed to design the decontamination approach. Initial sampling data collected by first responders are assessed to approximate the location(s) of contamination. Confirmation of the agent type and viability is obtained from a Laboratory Response Network laboratory. Additional characterization data are collected to determine the extent of contamination and where decontamination actions are needed. Areas suspected of being contaminated are contained and isolated to the degree possible to prevent further movement of an agent to uncontaminated areas or the environment, and to reduce the potential for future exposure from the agent or fumigant, if fumigation is needed. Agent air monitoring in areas adjacent to the contained contamination zones is done to ensure the protection of remediation personnel and to monitor any release from the contained zones. Various sampling approaches are considered. For example, wipe samples can be used to sample hard, nonporous surfaces. Swab samples can be used to sample nooks, crannies, joints, and seams. Appendix I is a template for preparing an incident-specific, operational characterization plan. Upon completion of the characterization plan, an internal review is initiated. Upon approval of the plan by the Unified Command, characterization commences. The Site Safety Officer develops a Health and Safety Plan to ensure that coordinated health and safety measures are in place for all responding personnel. This plan describes physical, chemical, and biological hazards at the site, personal protective equipment, personal decontamination procedures, and emergency procedures to be used by sampling and remediation personnel. An incident-specific Remediation Action Plan is developed, which describes the decontamination methods to be used and other details, including waste disposal. Under NIMS, this overall plan, as well as other plans described below, are implemented through a series of standardized, shorter-term Incident Action Plans, which describe specific activities that will take place during a shift or a day. The template in Appendix J is designed to facilitate preparation of the Remediation Action Plan. If fumigation will be done, a Sampling and Analysis Plan will be needed, as well as an Ambient Air Monitoring Plan, which can be a component of the Remediation Action Plan. These three plans are needed to obtain a crisis exemption from the U.S. Environmental Protection Agency for authorized use of an unregistered sterilant or pesticide during cleanup. If pesticide products become registered for inactivation of B. anthracis in the future, the three plans will likely be required by the product’s labeling, but the plans would no longer be submitted to the U.S. Environmental Protection Agency for approval; rather, the Incident Commander would approve them. If fumigation is used, an Emergency Response Plan is also recommended, although such a plan is not required for a crisis exemption. For some nonpersistent biological warfare agents, natural attenuation may be an adequate decontamination option. In cases where contamination is not extensive or an agent is not persistent, application of surface decontaminants or other methods of medical infection control may be effective. For extensive contamination by persistent agents, such as Bacillus anthracis, fumigation may be necessary. In those cases, the Decontamination Phase commences with source reduction, such as pre-cleaning surfaces to reduce the contaminant load. To expedite cleanup and prevent costs from escalating unnecessarily, a cost–benefit analysis should be incorporated in the decision process related to retention versus disposal of facility items and materials. Certain materials and structural components can be decontaminated for reuse, but it may not be feasible or cost-effective to decontaminate other items. Those items must be pre-treated, packaged (with the package decontaminated externally), and removed for disposal as waste. Site preparation includes sealing openings to prevent leaks and setting up equipment. Decontamination reagents and delivery systems are selected, and pre-testing all systems is done before carrying out chemical treatment(s). The important choice of decontamination technologies depends on characteristics of the agent, the nature and extent of contamination, and other site parameters identified during characterization. Decontamination-related decisions can have a major impact on waste-disposal costs, and it is necessary to develop a disposal plan that identifies a means of disposal, necessary approvals, transportation, and other details. A clearance strategy is developed to ensure that after decontamination, the risk of exposure to residual contamination is negligible. A clearance sampling plan is developed, which sets clearance criteria, specifies how to determine whether the criteria have been met, and describes how and where to collect clearance samples after decontamination. In most cases, clearance sampling includes both surface and aggressive air samples. Appendix K is a clearance plan template that identifies the types of required information. To determine whether the decontaminated area may be reoccupied, the Environmental Unit (and the ECC separately, if one is convened) evaluates the results of clearance samples. For the anthrax incidents to date, and given methods that have been used, cleanup was considered successful only when there was no growth of B. anthracis cultured from any environmental samples taken after decontamination. Other factors that will be considered include the decontamination process parameters (e.g., temperature, relative humidity, decontaminant concentration, and contact time) and the results from post-decontamination culture of biological indicators that may have been used during fumigation or sterilization processes. From such an evaluation the Environmental Unit or ECC, or both, recommend whether the area may be reoccupied, or whether further decontamination is necessary. The UC makes the final decision that a facility is appropriately decontaminated for reoccupancy. The facility owner or responsible public health agency makes the final decision to reopen a decontaminated facility. A theme that is emphasized throughout this document is that many activities can greatly reduce the time required to restore airport operations if those activities are conducted prior to an actual release of biological warfare agent. A summary of specific resources (such as Federal, state, and local agency contacts; contractors; prospective team members; subject-matter experts; laboratory facilities; and other entities) that should be identified in advance by airport officials is provided in each pertinent section of this document, and summary contact lists of such resources are provided in Appendix L. A summary of overall pre-planning actions that should be completed by airport officials is presented at the end of this document.

59 BASIC BIOLOGICAL SCIENCES↗

Characterizing model uncertainties in simulated coast-to-offshore wind over the northeast U.S. using multi-platform measurements from the TCAP field campaign

Numerical weather prediction (NWP) models, such as the Weather Research and Forecasting (WRF) model, are widely used to provide estimates of the offshore wind energy resource owing to their large spatial coverage compared to available observations. Nevertheless, spatiotemporal distribution of model biases is highly dependent on factors including model configuration, location, and the interplay of multi-scale physical processes. Here, in this study, we focus on the characterization of model uncertainties in simulated coast-to-offshore winds over the northeast U.S., by varying sea surface temperature (SST) forcings, surface layer (SL) and planetary boundary layer (PBL) parameterizations, as well as identifying biases that may be directly passed from initial and boundary conditions. Multiple measurements, including aircraft data collected during the U.S. Department of Energy's Two-Column Aerosol Project (TCAP) experiment, are used to constrain the model results and facilitate quantitative comparisons. Our analysis indicates while SST forcing has notable impacts on simulated air temperature and moisture within PBL, the modeled winds are in general more sensitive to the choices of SL and PBL physics than to SST. The model’s forcing data not only controls the vertical dependence of wind speed errors, but also alters regional variability in wind speed’s spatial correlation. Bias comparisons between ERA5 reanalysis and ensemble simulations revealed significant similarity, particularly in wind speed biases during winter, underscoring their dependency on initial and boundary conditions. Coastal and offshore near-surface wind speed biases tend to exhibit much higher similarity in winter than in summer due to the presence of much stronger and more persistent synoptic wind conditions. This study highlights the importance of accurate atmospheric forcing and parameterization choices in improving wind forecasts and suggests the potential for extrapolating coastal wind biases to offshore locations, aiding wind energy forecasting and informing the Wind Forecast Improvement Project-3 (WFIP3).

17 WIND ENERGY↗

Potential biological control agents of Geosmithia morbida restrict fungal pathogen growth via mycoparasitism and antibiosis

Abstract Thousand cankers disease of Juglans (walnut) and Pterocarya (wingnut) spp. (Fagales: Juglandaceae) is caused by the fungal pathogen Geosmithia morbida Kolarík, Freeland, Utley, and Tisserat (Hypocreales: Bionectriaceae) and bark beetle pest/vector, Pityophthorus juglandis Blackman (Coleoptera: Curculionidae). To further the development of biological management strategies for thousand cankers disease, we assessed the ability of 14 endophytic Trichoderma (Hypocreales: Hypocreaceae) isolates and the commercially available isolate T. afroharzianum strain KRL-AG2 to inhibit the in vitro growth of three different G. morbida isolates via mycoparasitism and antibiosis. To identify factors that may affect field success of candidate biological control agents, we quantified the growth responses of Trichoderma spp. and the commercially available entomopathogenic fungus, Beauveria bassiana (Bals.-Criv.) Vuill. (Hypocreales: Cordycipitaceae) strain GHA, to the plant secondary metabolite and antimicrobial compound, juglone in vitro. A total of 12 Trichoderma isolates (from six different Trichoderma species) demonstrated antagonistic activity towards G. morbida in dual-plate assays. Juglone consistently reduced the growth of B. bassiana strain GHA and 14 of the 15 screened Trichoderma isolates in vitro. Additionally, one metabolite-producing Trichoderma isolate, TN4-47, completely inhibited the growth of all three G. morbida isolates across all tested metabolite concentrations and had comparatively greater tolerance to juglone compared to other Trichoderma isolates. Future lines of research should focus on characterizing the active antagonistic compound present in the metabolite filtrates, determine the mode of action of the active component(s), and elucidate how abiotic and biotic factors may influence the growth, persistence, and antagonistic activity of candidate biological control agents in planta .

59 BASIC BIOLOGICAL SCIENCES↗

Final Report: Sublinear Algorithms for In-situ and In-transit Data Analysis at Exascale.

Post-Moore's law scaling is creating a disruptive shift in simulation workflows, as saving the entirety of raw data to persistent storage becomes expensive. We are moving away from a post-process centric data analysis paradigm towards a concurrent analysis framework, in which raw simulation data is processed as it is computed. Algorithms must adapt to machines with extreme concurrency, low communication bandwidth, and high memory latency, while operating within the time constraints prescribed by the simulation. Furthermore, in- put parameters are often data dependent and cannot always be prescribed. The study of sublinear algorithms is a recent development in theoretical computer science and discrete mathematics that has significant potential to provide solutions for these challenges. The approaches of sublinear algorithms address the fundamental mathematical problem of understanding global features of a data set using limited resources. These theoretical ideas align with practical challenges of in-situ and in-transit computation where vast amounts of data must be processed under severe communication and memory constraints. This report details key advancements made in applying sublinear algorithms in-situ to identify features of interest and to enable adaptive workflows over the course of a three year LDRD. Prior to this LDRD, there was no precedent in applying sublinear techniques to large-scale, physics based simulations. This project has definitively demonstrated their efficacy at mitigating high performance computing challenges and highlighted the rich potential for follow-on re- search opportunities in this space.

97 MATHEMATICS AND COMPUTING↗

An evaluation of ERTS data for oceanographic uses through Great Lakes studies

The author has identified the following significant results. Prevailing wind direction on Lake Michigan is southwesterly, although during winter northwesterly stresses are common. Along the western shore the current favors a northward direction. ERTS-1 observations indicate that the southward-flowing current along the Michigan shoreline of the thumb is only reversed by southerly resultant wind stress. Along the Canadian shoreline, a northward current was observed north of Kettle Point. ERTS-1 data also reveal that a preferred southward-flowing current is found along the Detroit shoreline of Lake St. Clair. Eastward flow of surface water from the shallow western basin of Lake Erie into the middle basin is most obvious during northwesterly and northerly wind stresses. The reverse wind direction especially east and southeasterly, appear to hold the effluents from the Detroit and Maumee Rivers in the western basin. Across-lake winds from the north and south induce eddy-like circulation in surface waters of Lake Ontario. Counterclockwise alongshore flow persists in the western basin under most wind conditions.

Strong, A. E.↗

Characterization of PVT Grown ZnSe by Low Temperature Photoluminescence

ZnSe, a II-VI semiconductor with a large direct band gap of 2.7 eV at room temperature and 2.82 eV at 10 K, is considered a promising material for optoelectric applications in the blue-green region of the spectrum. Photoemitting devices and diode laser action has been demonstrated as a result of decades of research. A key issue in the development of II-VI semiconductors is the control of the concentration of the various impurities. The II-VI semiconductors seem to defy the effort of high level doping due to the well known self compensation of the donors and the acceptors. A good understanding of roles of the impurities and the behavior of the various intrinsic defects such as vacancies, interstitials and their complexes with impurities is necessary in the development and application of these materials. Persistent impurities such as Li and Cu have long played a central role in the photoelectronic properties of many II-VI compounds, particularly ZnSe. The shallow centers which may promote useful electrical conductivity are of particular interest. They contribute the richly structured near gap edge luminescence, containing weak to moderate phonon coupling and therefore very accessible information about the energy states of the different centers. Significance of those residual impurities which may contribute such centers in II-VI semiconductors must be fully appreciated before improved control of their electrical properties may be possible. Low temperature photoluminescence spectroscopy is an important source of information and a useful tool of characterization of II-VI semiconductors such as ZnSe. The low temperature photoluminescence spectrum of a ZnSe single crystal typically consists of a broad band emission peaking at 2.34 eV, known as the Cu-green band, and some very sharp lines near the band gap. These bands and lines are used to identify the impurity ingredients and the defects. The assessment of the quality of the crystal based on the photoluminescence analysis is then possible. In this report we present the characterization of a ZnSe single crystal as grown by the physical vapor transport method, with special intention paid to the possible effects of the gravitational field to the growth of the crystal.

Wang, Ling Jun↗