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NASA NTRS1973

ERTS evaluation for land use inventory

The author has identified the following significant results. The feasibility of accomplishing a general inventory of any given region based on spectral categories from satellite data has been demonstrated in a pilot study for an area of 6300 square kilometers in central New York State. This was accomplished by developing special processing techniques to improve and balance contrast and density for each spectral band of an image scene to compare with a standard range of density and contrast found to be acceptable for interpretation of the scene. Diazo film transparencies were made from enlarged black and white transparencies of each spectral band. Color composites were constructed from these diazo films in combinations of hue and spectral bands to enhance different spectral features in the scene. Interpretation and data takeoff was accomplished manually by translating interpreted areas onto an overlay to construct a spectral map. The minimum area interpreted was 25 hectares. The minimum area geographically referenced was one square kilometer. The interpretation and referencing of data from ERTS-1 was found to be about 88% accurate for eight primary spectral categories.

Hardy, E. E.↗

DOE OSTI2013

Comparison of Stack Measurement Data from R&D Facilities to Regulatory Criteria. A Case Study from PNNL

Chemical emissions from research and development (R&D) activities are difficult to estimate because of the large number of chemicals used and the potential for continual changes in processes. In this case study, stack measurements taken from R&D facilities at Pacific Northwest National Laboratory (PNNL) were examined, including extreme worst-case emissions estimates and alternate analyses using a Monte Carlo method that takes into account the full distribution of sampling results. The results from these analyses were then compared to emissions estimated from chemical inventories. Results showed that downwind ambient air concentrations calculated from the stack measurement data were below acceptable source impact levels (ASILs) for almost all compounds, even under extreme worst-case analyses. However, for compounds with averaging periods of a year, the unrealistic but simplifying extreme worst-case analysis often resulted in exceedances of lower level regulatory criteria used to determine modeling requirements or to define trivial releases. Compounds with 24-hour averaging periods were nearly all several orders of magnitude below all, including the trivial release, criteria. The alternate analysis supplied a more realistic basis of comparison and an ability to explore effects under different operational modes.

54 ENVIRONMENTAL SCIENCES↗

NASA NTRS1979

Computer Technology for Industry

In this age of the computer, more and more business firms are automating their operations for increased efficiency in a great variety of jobs, from simple accounting to managing inventories, from precise machining to analyzing complex structures. In the interest of national productivity, NASA is providing assistance both to longtime computer users and newcomers to automated operations. Through a special technology utilization service, NASA saves industry time and money by making available already developed computer programs which have secondary utility. A computer program is essentially a set of instructions which tells the computer how to produce desired information or effect by drawing upon its stored input. Developing a new program from scratch can be costly and time-consuming. Very often, however, a program developed for one purpose can readily be adapted to a totally different application. To help industry take advantage of existing computer technology, NASA operates the Computer Software Management and Information Center (COSMIC)(registered TradeMark),located at the University of Georgia. COSMIC maintains a large library of computer programs developed for NASA, the Department of Defense, the Department of Energy and other technology-generating agencies of the government. The Center gets a continual flow of software packages, screens them for adaptability to private sector usage, stores them and informs potential customers of their availability.

Source record↗

NASA NTRS2020

Assessment of Lidar XCH4 Measurements During ACT-America 2019 for Boundary Layer Methane and Emission Model Constraint

Atmospheric methane is a potent and abundant greenhouse gas (GHG) with increasing importance due to rising emissions and their subsequent impact on radiative forcing, indicating an important driving role in climate change. The recent Earth Science Decadal Survey called for further understanding of the sources and sinks of atmospheric methane, the processes that will affect their future concentrations, and identified the need for advanced observing capabilities to elucidate these issues. HALO, a combined methane Differential Absorption Lidar and Aerosol/Cloud High Spectral Resolution Lidar participated in the ACT-America summer 2019 campaign to help constrain the emissions and transport of GHGs in the atmosphere to address some of the aforementioned science goals. In this presentation we will discuss the utility of using an in-situ point measurement versus lidar column measurement for inventory and source identification applications. Comparisons between column measurements of methane from in-situ and lidar will be made to assess whether point measurements are useful when the assumption of a well-mixed boundary layer, a practice commonly used in the community, is valid. We will also show that a lidar column measurement can apportion boundary layer methane from the column and has the ability to identify boundary layer methane enhancements in fair weather conditions using atmospheric backscatter signals, a measurement capability that has the potential to transform the observational strategies of future airborne carbon cycle science investigations. We will also present on the differences and utility of constraining emission models using an in-situ versus lidar column and asses the resulting uncertainties of each.

Rory A Barton-Grimley↗

NASA NTRS1974

Statistical theory and methodology for remote sensing data analysis

A model is developed for the evaluation of acreages (proportions) of different crop-types over a geographical area using a classification approach and methods for estimating the crop acreages are given. In estimating the acreages of a specific croptype such as wheat, it is suggested to treat the problem as a two-crop problem: wheat vs. nonwheat, since this simplifies the estimation problem considerably. The error analysis and the sample size problem is investigated for the two-crop approach. Certain numerical results for sample sizes are given for a JSC-ERTS-1 data example on wheat identification performance in Hill County, Montana and Burke County, North Dakota. Lastly, for a large area crop acreages inventory a sampling scheme is suggested for acquiring sample data and the problem of crop acreage estimation and the error analysis is discussed.

Odell, P. L.↗

NASA NTRS2007

Prompt and Afterglow Emission Properties of Gamma-Ray Bursts with Spectroscopically Identified Supernovae

We present a detailed spectral analysis of the prompt and afterglow emission of four nearby long-soft gamma-ray bursts (GRBs 980425,030329,031203, and 060218) that were spectroscopically found to be associated with Type Ic supernovae and compare them to the general GRB population. For each event, we investigate the spectral and luminosity evolution and estimate the total energy budget based on broadband observations. The observational inventory for these events has become rich enough to allow estimates of their energy content in relativistic and subrelativistic form. The result is a global portrait of the effects of the physical processes responsible for producing long-soft GRBs. In particular, we find that the values of the energy released in mildly relativistic outflows appears to have a significantly smaller scatter than those found in highly relativistic ejecta. This is consistent with a picture in which the energy released inside the progenitor star is roughly standard, while the fraction of that energy that ends up in highly relativistic ejecta outside the star can vary dramatically between different events.

Kaneko, Yuki↗

NASA NTRSDate not supplied

PRESOLAR GRAIN ABUNDANCE VARIATION IN THE MILLER RANGE 090019 CO3.1 CHONDRITE

Presolar grains condensed in the outflows of evolved red giant stars and the ejecta of supernovae (SNe) and novae. These grains have greatly anomalous isotopic compositions compared to solar system material, reflecting their stellar origins [1]. They have been identified in primitive meteorites, interplanetary dust particles (IDPs), Antarctic micrometeorites, and comet Wild 2 samples returned by NASA’s Stardust mission. Presolar silicates are one of the most abundant presolar phases and their concentrations extend up to 1.5% in primitive IDPs believed to derive from comets [2]. These grains are highly susceptible to alteration and destruction by secondary processing in the interstellar medium, nebula, and asteroid or comet parent body. Presolarsilicate abundance variations between primitive meteorites and chemical and mineralogical studies provide indications of the extent of secondary hydrothermal alteration [3, 4]. The abundance of presolar SiC grains is generally consistent among chondrites, but lower abundances in some meteorites have been attributed to thermal alteration [5, 6]. Presolar grain abundance variations attributed to localized alteration have also been reported within different regions of a chondrite [e.g., 7].Carbonaceous chondrites from the CO and CR groups have the highest abundances of presolar silicates among meteorites, attesting to their primitive nature. The CO3 chondrite Dominion Range (DOM) 08006 has the highest presolar O-rich grain abundance of ~260 ppm [8, 9]. MillerRange (MIL) 090019 is classified as a CO3.1 chondrite and has affinities to Acfer 094, DOM 08004/6 and Allan Hills (ALH) 77307. These chondrites have high presolar silicate abundances and contain high abundances of various types of refractory inclusions. We previously conducted detailed studies of CAIs in MIL 090019 [10, 11]. Here we evaluate its presolar grain inventory to assess the degree of parent body alteration and compare to other chondrites

A. N. Nguyen↗

DOE OSTI2013

Estimating Alarm Thresholds for Process Monitoring Data under Different Assumptions about the Data Generating Mechanism

Process monitoring (PM) for nuclear safeguards sometimes requires estimation of thresholds corresponding to small false alarm rates. Threshold estimation dates to the 1920s with the Shewhart control chart; however, because possible new roles for PM are being evaluated in nuclear safeguards, it is timely to consider modern model selection options in the context of threshold estimation. One of the possible new PM roles involves PM residuals, where a residual is defined as residual = data − prediction. This paper reviews alarm threshold estimation, introduces model selection options, and considers a range of assumptions regarding the data-generating mechanism for PM residuals. Two PM examples from nuclear safeguards are included to motivate the need for alarm threshold estimation. The first example involves mixtures of probability distributions that arise in solution monitoring, which is a common type of PM. The second example involves periodic partial cleanout of in-process inventory, leading to challenging structure in the time series of PM residuals.

Burr, Tom↗

NASA NTRS2015

Development of Test Protocols for International Space Station Particulate Filters

Air quality control on the International Space Station (ISS) is a vital requirement for maintaining a clean environment for the crew and the hardware. This becomes a serious challenge in pressurized space compartments since no outside air ventilation is possible, and a larger particulate load is imposed on the filtration system due to lack of gravitational settling. The ISS Environmental Control and Life Support System (ECLSS) uses a filtration system that has been in use for over 14 years and has proven to meet this challenge. The heart of this system is a traditional High-Efficiency Particulate Air (HEPA) filter configured to interface with the rest of the life support elements and provide effective cabin filtration. The filter element for this system has a non-standard cross-section with a length-to-width ratio (LW) of 6.6. A filter test setup was designed and built to meet industry testing standards. A CFD analysis was performed to initially determine the optimal duct geometry and flow configuration. Both a screen and flow straighter were added to the test duct design to improve flow uniformity and face velocity profiles were subsequently measured to confirm. Flow quality and aerosol mixing assessments show that the duct flow is satisfactory for the intended leak testing. Preliminary leak testing was performed on two different ISS filters, one with known perforations and one with limited use, and results confirmed that the testing methods and photometer instrument are sensitive enough to detect and locate compromised sections of an ISS BFE.Given the engineering constraints in designing spacecraft life support systems, it is anticipated that non-industry standard filters will be required in future designs. This work is focused on developing test protocols for testing the ISS BFE filters, but the methodology is general enough to be extended to other present and future spacecraft filters. These techniques for characterizing the test duct and perform leak testing can be applied to conducting acceptance testing and inventory testing for future manned exploration programs with air revitalization filtration needs, possibly even for in-situ filter element integrity testing for extensively long-duration missions. We plan to address the unique needs for test protocols for crewed spacecraft particulate filters by preparing the initial version of a standard, to be documented as a NASA Technical Memorandum (TM).

Filtration↗

DOE OSTI2018

Portable Flux Tower Deployments Field Campaign Report

In May of 2015, a portable eddy covariance flux tower was installed by David Billesbach at the U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) user facility’s Southern Great Plains (SGP) observatory E-32 extended facility west of Medford, Oklahoma. The goal of this deployment was to provide data sets that could be used to test land-atmosphere models and surface forcing from the SGP region. This site was chosen as being underrepresented in current data inventories. In January of 2016, a second portable flux system was installed (by Billesbach and Sebastien Biraud) in a field at the southeast corner of the intersection of Oklahoma highways 11 and 74 (also near Medford and designated as site 74). This site was chosen because it was to be planted in grain sorghum (milo) which is also an underrepresented crop. A secondary goal for this deployment was to refine the operational parameters of the newly rebuilt portable eddy correlation flux systems (ECOR), which incorporate several new sensors. These new measurements were designed to accommodate more advanced modeling and integration with remote-sensing products such as normalized difference vegetation index (NDVI), photochemical reflectance index (PRI), and diffuse solar radiation. Another secondary goal was to assess how well surface energy components—sensible heat flux (H) and latent heat flux (LE)—measured by ECOR and energy balance Bowen ratio (EBBR) instruments could be compared. Operations were terminated at the E-32 site in June of 2017 and Billesbach removed the equipment from the site. Operations at site 74 were terminated in October of 2017 and Billesbach (with assistance from SGP-Central Facility personnel) again removed the equipment from the field. The most notable event at the E-32 site was the retrenching of site power. This operation opened a wide gap in the normally grass-covered footprint of our optical sensors. We are still evaluating the effects that the bare soil had on our NDVI and PRI data. At site 74, we learned after germination that soy beans instead of grain sorghum had been planted for the second (2017) growing season.

energy balance Bowen ratio station, eddy correlati↗

DOE OSTI2015

Delayed Gamma-Ray Spectroscopy for Non-Destructive Assay of Nuclear Materials

High-energy, beta-delayed gamma-ray spectroscopy is a potential, non-destructive assay techniques for the independent verification of declared quantities of special nuclear materials at key stages of the fuel cycle and for directly assaying nuclear material inventories for spent fuel handling, interim storage, reprocessing facilities, repository sites, and final disposal. Other potential applications include determination of MOX fuel composition, characterization of nuclear waste packages, and challenges in homeland security and arms control verification. Experimental measurements were performed to evaluate fission fragment yields, to test methods for determining isotopic fractions, and to benchmark the modeling code package. Experimental measurement campaigns were carried out at the IAC using a photo-neutron source and at OSU using a thermal neutron beam from the TRIGA reactor to characterize the emission of high-energy delayed gamma rays from 235 U, 239 Pu, and 241 Pu targets following neutron induced fission. Data were collected for pure and combined targets for several irradiation/spectroscopy cycle times ranging from 10/10 seconds to 15/30 minutes.The delayed gamma-ray signature of 241 Pu, a significant fissile constituent in spent fuel, was measured and compared to 239 Pu. The 241 Pu/ 239 Pu ratios varied between 0.5 and 1.2 for ten prominent lines in the 2700-3600 keV energy range. Such significant differences in relative peak intensities make it possible to determine relative fractions of these isotopes in a mixed sample. A method for determining fission product yields by fitting the energy and time dependence of the delayed gamma-ray emission was developed and demonstrated on a limited 235 U data set. De-convolution methods for determining fissile fractions were developed and tested on the experimental data. The use of high count-rate LaBr 3 detectors was investigated as a potential alternative to HPGe detectors. Modeling capabilities were added to an existing framework and codes were adapted as needed for analyzing experiments and assessing application-specific assay concepts. A de-convolution analysis of the delayed gamma-ray response spectra modeled for spent fuel assemblies was performed using the same method that was applied to the experimental spectra.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

DOE OSTI2018

The Origin of Titan’s External Oxygen: Further Constraints from ALMA Upper Limits on CS and CH{sub 2}NH

Titan’s atmospheric inventory of oxygen compounds (H{sub 2}O, CO{sub 2}, CO) are thought to result from photochemistry acting on externally supplied oxygen species (O{sup +}, OH, H{sub 2}O). These species potentially originate from two main sources: (1) cryogenic plumes from the active moon Enceladus and (2) micrometeoroid ablation. Enceladus is already suspected to be the major O{sup +} source, which is required for CO creation. However, photochemical models also require H{sub 2}O and OH influx to reproduce observed quantities of CO{sub 2} and H{sub 2}O. Here, we exploit sulphur as a tracer to investigate the oxygen source because it has very different relative abundances in micrometeorites (S/O ∼ 10{sup −2}) and Enceladus’ plumes (S/O ∼ 10{sup −5}). Photochemical models predict most sulphur is converted to CS in the upper atmosphere, so we use Atacama Large Millimeter/submillimeter Array (ALMA) observations at ∼340 GHz to search for CS emission. We determined stringent CS 3σ stratospheric upper limits of 0.0074 ppb (uniform above 100 km) and 0.0256 ppb (uniform above 200 km). These upper limits are not quite stringent enough to distinguish between Enceladus and micrometeorite sources at the 3σ level and a contribution from micrometeorites cannot be ruled out, especially if external flux is toward the lower end of current estimates. Only the high-flux micrometeorite source model of Hickson et al. can be rejected at 3σ. We determined a 3σ stratospheric upper limit for CH{sub 2}NH of 0.35 ppb, which suggests cosmic rays may have a smaller influence in the lower stratosphere than predicted by some photochemical models. Disk-averaged C{sub 3}H{sub 4} and C{sub 2}H{sub 5}CN profiles were determined and are consistent with previous ALMA and Cassini/CIRS measurements.

79 ASTRONOMY AND ASTROPHYSICS↗

DOE OSTI2013

SRS K-AREA MATERIAL STORAGE - EXPANDING CAPABILITIES

In support of the Department of Energy’s continued plans to de-inventory and reduce the footprint of Cold War era weapons’ material production sites, the K-Area Material Storage (KAMS) facility, located in the K-Area Complex (KAC) at the Savannah River Site reservation, has expanded since its startup authorization in 2000 to accommodate DOE’s material consolidation mission. During the facility’s growth and expansion, KAMS will have expanded its authorization capability of material types and storage containers to allow up to 8200 total shipping containers once the current expansion effort completes in 2014. Recognizing the need to safely and cost effectively manage other surplus material across the DOE Complex, KAC is constantly evaluating the storage of different material types within K area. When modifying storage areas in KAC, the Documented Safety Analysis (DSA) must undergo extensive calculations and reviews; however, without an extensive and proven security posture the possibility for expansion would not be possible. The KAC maintains the strictest adherence to safety and security requirements for all the SNM it handles. Disciplined Conduct of Operations and Conduct of Projects are demonstrated throughout this historical overview highlighting various improvements in capability, capacity, demonstrated cost effectiveness and utilization of the KAC as the DOE Center of Excellence for safe and secure storage of surplus SNM.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

NASA NTRS1985

Venus, Earth and Mars: Present bounds on similarities and differences in bulk composition

The bulk compositions of the terrestrial planets are constrained in part by rigorous bounds derivable from geophysical data and from chemical data obtained in situ or by remote sensing. In large part, however, the bulk compositions are constrained only by the inferred plausibility of assumptions made about the processes responsible for producing planets. Present data are consistent with Venus, Earth and Mars all having solar ratios of the major, non-volatile elements. The mantle of Mars has a higher FeO content than the Earth's present upper mantle. The FeO content of the Venus mantle is poorly constrained. Abundances of minor elements are virtually unconstrained by geophysical data and only weakly constrained by existing chemical data. Inferences drawn from SNC meteorites suggest that Mars may be enriched in most volatiles relative to the Earth. Simple models in which volatiles are added in a single component probably do not accurately predict bulk volatile inventories of the planets.

Goettel, K. A.↗

DOE OSTI2018

Simulator of Non-homogenous Alumina and Current Distribution in an Aluminum Electrolysis Cell to Predict Low-Voltage Anode Effects

Perfluorocarbons are important contributors to aluminum production greenhouse gas inventories. Tetrafluoromethane and hexafluoroethane are produced in the electrolysis process when a harmful event called anode effect occurs in the cell. This incident is strongly related to the lack of alumina and the current distribution in the cell and can be classified into two categories: high-voltage and low-voltage anode effects. The latter is hard to detect during the normal electrolysis process and, therefore, new tools are necessary to predict this event and minimize its occurrence. This paper discusses a new approach to model the alumina distribution behavior in an electrolysis cell by dividing the electrolytic bath into non-homogenous concentration zones using discrete elements. The different mechanisms related to the alumina distribution are discussed in detail. Moreover, with a detailed electrical model, it is possible to calculate the current distribution among the different anodic assemblies. With this information, the model can evaluate if low-voltage emissions are likely to be present under the simulated conditions. Using the simulator will help the understanding of the role of the alumina distribution which, in turn, will improve the cell energy consumption and stability while reducing the occurrence of high- and low-voltage anode effects.

36 MATERIALS SCIENCE↗

DOE OSTI2019

Quantification of Soil Organic Carbon in Biochar-Amended Soil Using Ground Penetrating Radar (GPR)

The application of biochar amendments to soil has been proposed as a strategy for mitigating global carbon (C) emissions and soil organic carbon (SOC) loss. Biochar can provide additional agronomic benefits to cropping systems, including improved crop yield, soil water holding capacity, seed germination, cation exchange capacity (CEC), and soil pH. To maximize the beneficial effects of biochar amendments towards the inventory, increase, and management of SOC pools, nondestructive analytical methods such as ground penetrating radar (GPR) are needed to identify and quantify belowground C. The use of GPR has been well characterized across geological, archaeological, engineering, and military applications. While GPR has been predominantly utilized to detect relatively large objects such as rocks, tree roots, land mines, and peat soils, the objective of this study was to quantify comparatively smaller, particulate sources of SOC. This research used three materials as C sources: biochar, graphite, and activated C. The C sources were mixed with sand—12 treatments in total—and scanned under three moisture levels: 0%, 10%, and 20% to simulate different soil conditions. GPR attribute analyses and Naïve Bayes predictive models were utilized in lieu of visualization methods because of the minute size of the C particles. Significant correlations between GPR attributes and both C content and moisture levels were detected. The accuracy of two predictive models using a Naïve Bayes classifier for C content was trivial but the accuracy for C structure was 56%. The analyses confirmed the ability of GPR to identify differences in both C content and C structure. Beneficial future applications could focus on applying GPR across more diverse soil conditions.

54 ENVIRONMENTAL SCIENCES↗

NASA NTRS2018

Igneous Rocks Formed by Hypervelocity Impact

Igneous rocks are the primary building blocks of planetary crusts. Most igneous rocks originate via decompression melting and/or wet melting of protolith lithologies within planetary interiors and their classification and compositional, petrographic, and textural characteristics, arewell-studied. As our exploration of the Solar System continues, so too does the inventory of intrusive and extrusive igneous rocks, settings, and processes. The results of planetary exploration have also clearly demonstrated that impact cratering is a ubiquitous geological process that has affected, andwill continue to affect, all planetary objectswith a solid surface,whether that be rock or ice. It is nowrecognized that the production of igneous rocks is a fundamental outcome of hypervelocity impact. The goal of this review is to provide an up-to-date synthesis of our knowledge and understanding of igneous rocks formed by hypervelocity impact. Following a brief overview of the basics of the impact process, we describe howand whymelts are generated during impact events and howimpactmelting differs fromendogenic igneous processes.While the processmay differ,we showthat the products of hypervelocity impact can share close similarities with volcanic and shallow intrusive igneous rocks of endogenic origin. Such impact melt rocks, as they are termed, can display lobate margins and cooling cracks, columnar joints and at the hand specimen andmicroscopic scale, such rocks can displaymineral textures that are typical of volcanic rocks, such as quench crystallites, ophitic, porphyritic, aswell as features such as vesicles, flowtextures, and so on.Historically, these similarities led to themisidentification of some igneous rocks now known to be impact melt rocks as being of endogenic origin. This raises the question as to how to distinguish between an impact versus an endogenic origin for igneous-like rocks on other planetary bodies where fieldwork and sample analysis may not be possible and all that may be available is remote sensing data.While the interpretation of some impact melt rocks may be relatively straightforward (e.g., for clast-rich varieties and those with clear projectile contamination) we conclude that distinguishing between impact and endogenic igneous rocks is a non-trivial task that ultimately may require sample investigation and analysis to be conducted. Caution is, therefore, urged in the interpretation of igneous rocks on planetary surfaces.

Osinski, Gordon R.↗

NASA NTRS2001

A sleep diary and questionnaire study of naturally short sleepers

Whereas most people require more than 6 h of sleep to feel well rested, there appears to be a group of people who can function well on between 3 and 6 h of sleep. The aims of the present study were to compare 12 naturally short (3-6 h) sleepers (9 males 3 females, mean age 39.6 years, SD age 10.1 years) recruited by a media publicity campaign with age, gender and chronotype matched medium length (7-8.5 h) sleepers on various measures. Measurement instruments included diaries and questionnaires to assess sleep duration and timing, as well as questionnaire assessments of sleep pathology, morningness-eveningness, extroversion, neuroticism, pathological daytime sleepiness, subclinical hypomania, optimism, depressive symptoms, exercise, and work habits. Few measures showed reliable differences between naturally short sleepers and controls except the obvious ones related to sleep duration. There was, however, some evidence for subclinical hypomanic symptoms in naturally short sleepers.

NASA Discipline Regulatory Physiology↗