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All sourcesNASA NTRSDOE OSTI
DOE OSTI2019

HAMT extension for EnergyPlus encompasses moisture sources due to air leakage

As building envelopes become more energy efficient, new buildings are more prone to hygrothermal failure. The combined Heat and Moisture Transfer (HAMT) model in EnergyPlus is able to provide moisture profiles through multiple material layers of an envelope assembly using a coupled, one-dimensional, finite element model simulating the movement and storage of heat and moisture. However, HAMT is currently unable to properly assess the effects of moisture sources inside an assembly to determine impacts on durability, indoor air quality, and energy performance.This paper reviews existing tools for modeling moisture sources due to air leakage and the HAMT model equations in EnergyPlus. A sub-model is then developed that enables air leakage to be applied to a moisture sink/source at an arbitrary location by extending the existing mass transfer equation with a source term that includes water vapor deposit from air flow through an assembly. We demonstrate use of this model, discuss limitations, and make the source code publicly available for external use.

Antretter, Florian↗
NASA NTRS1987

Numerical simulations of magnetospheric plasmas - Review and quadrennial report to the IUGG

This article provides a broad survey of U.S. progress during the quadrennium 1983-1986 in the category 'numerical simulations of magnetospheric plasmas'. There has been a substantial increase of activity in this area during this period. Simulations have been instrumental in providing valuable insights into large scale dynamic phenomena, nonlinear effects, and complex kinetic phenomena in a wide variety of subject areas, including shocks and double layers, ionosphere-magnetosphere coupling phenomena, and important microphysical processes such as broadband electrostatic noise. The methodology of computer simulation has also been advanced during this quadrennium. Vlasov algorithms have been improved; hybrid codes in 2 and 3D have been developed and applied to magnetospheric problems; and complex problems have been subjected with increasing frequency to a multipronged attack in which several types of simulation models, each designed to accurately model phenomena within a particular range of temporal or spatial scales, are employed synergistically.

Palmadesso, Peter J.↗
DOE OSTI2023

U.S. Efforts in Support of Examinations at Fukushima Daiichi - November 2022 Meeting Notes and Information Request Status

Information obtained from Fukushima Daiichi Nuclear Power Station (Daiichi) is required to inform future Decontamination and Decommissioning (D&D) activities, improving the ability of the Tokyo Electric Power Company Holdings, Incorporated (TEPCO Holdings) to characterize potential hazards and to ensure the safety of workers involved with cleanup activities. This information also has important implications for the safety and operation of U.S. commercial nuclear power plants. This document summarizes results from the Fiscal Year 2023 (FY2023) U.S. effort to review Daiichi information and extract insights to enhance the safety of existing and future nuclear power plant designs. This U.S. effort, which was initiated in 2014 by the Department of Energy Office of Nuclear Energy, is completed by a group of experts in reactor safety and plant operations that identify examination needs and evaluate recent Daiichi examination data to address these needs. Fukushima-related information and associated discussions during these meetings benefit operating, new, and advanced reactors. Significant safety insights have been and are continuing to be obtained in several areas: system and component performance, radionuclide surveys and sampling, debris end-state location, combustible gas effects, and plant operations and maintenance. In addition to reducing uncertainties related to severe accident modeling progression, these insights have and continue to be used to update guidance for severe accident prevention, mitigation, and emergency planning. Furthermore, Daiichi-related activities, such as code modeling improvements and analysis, testing, and new technology deployment efforts, have the potential to offer additional benefits to the operating fleet and new LWR and non-LWR designs. U.S. evaluations of obtained examination information and input regarding future Daiichi examinations are of interest to several organizations within Japan. Since its inception, the U.S. has provided consensus input for high priority time-sequenced examination tasks and supporting research activities. In their Mid-to-Long-term Examination Plan for 1F investigations, TEPCO included all remaining U.S. consensus information requests and additional information requests they identified. TEPCO periodically provides reports on the status of these requests (reflecting D&D priorities, new insights from investigations, and new technologies that become available). Hence, U.S. experts agreed that it was appropriate for TEPCO to track and prioritize these information requests as D&D progresses. U.S. experts will continue to review and comment on the information obtained from examinations and, as needed, provide additional details and relevant background material to support future examinations. As documented in this report, several other items, such as additional details on information requests pertaining to ex-vessel examinations, relevant references from prior research, additional documents to provide insights regarding recent investigation findings, and reviews of recently released documents, were agreed to during the FY2023 meeting.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
DOE OSTI2013

Implementation of Remote 3-Dimensional Image Guided Radiation Therapy Quality Assurance for Radiation Therapy Oncology Group Clinical Trials

Purpose: To report the process and initial experience of remote credentialing of three-dimensional (3D) image guided radiation therapy (IGRT) as part of the quality assurance (QA) of submitted data for Radiation Therapy Oncology Group (RTOG) clinical trials; and to identify major issues resulting from this process and analyze the review results on patient positioning shifts. Methods and Materials: Image guided radiation therapy datasets including in-room positioning CT scans and daily shifts applied were submitted through the Image Guided Therapy QA Center from institutions for the IGRT credentialing process, as required by various RTOG trials. A centralized virtual environment is established at the RTOG Core Laboratory, containing analysis tools and database infrastructure for remote review by the Physics Principal Investigators of each protocol. The appropriateness of IGRT technique and volumetric image registration accuracy were evaluated. Registration accuracy was verified by repeat registration with a third-party registration software system. With the accumulated review results, registration differences between those obtained by the Physics Principal Investigators and from the institutions were analyzed for different imaging sites, shift directions, and imaging modalities. Results: The remote review process was successfully carried out for 87 3D cases (out of 137 total cases, including 2-dimensional and 3D) during 2010. Frequent errors in submitted IGRT data and challenges in the review of image registration for some special cases were identified. Workarounds for these issues were developed. The average differences of registration results between reviewers and institutions ranged between 2 mm and 3 mm. Large discrepancies in the superior-inferior direction were found for megavoltage CT cases, owing to low spatial resolution in this direction for most megavoltage CT cases. Conclusion: This first experience indicated that remote review for 3D IGRT as part of QA for RTOG clinical trials is feasible and effective. The magnitude of registration discrepancy between institution and reviewer was presented, and the major issues were investigated to further improve this remote evaluation process.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2018

Distance Metrics and Clustering Methods for Mixed-type Data

In spite of the abundance of clustering techniques and algorithms, clustering mixed interval (continuous) and categorical (nominal and/or ordinal) scale data remain a challenging problem. In order to identify the most effective approaches for clustering mixed–type data, we use both theoretical and empirical analyses to present a critical review of the strengths and weaknesses of the methods identified in the literature. Here, the guidelines on approaches to use under different scenarios are provided, along with potential directions for future research.

97 MATHEMATICS AND COMPUTING↗
NASA NTRS1990

Computer codes for the evaluation of thermodynamic properties, transport properties, and equilibrium constants of an 11-species air model

The computer codes developed provide data to 30000 K for the thermodynamic and transport properties of individual species and reaction rates for the prominent reactions occurring in an 11-species nonequilibrium air model. These properties and the reaction-rate data are computed through the use of curve-fit relations which are functions of temperature (and number density for the equilibrium constant). The curve fits were made using the most accurate data believed available. A detailed review and discussion of the sources and accuracy of the curve-fitted data used herein are given in NASA RP 1232.

Thompson, Richard A.↗
NASA NTRS2004

Overview: Small Aircraft Transportation System Airborne Remote Sensing Fuel Droplet Evaporation

The NASA Nebraska Preparation Grant was designed to solidify relationships, intensify communication, and launch collaborative initiatives among Nebraska researchers and key contacts at NASA research centers and enterprises. In doing so, Nebraska was successful in laying the groundwork for the foundation for numerous long-term, mutually beneficial collaborations that were subsequently proposed and awarded in the NASA EPSCoR 2000 competition. The NASA Nebraska EPSCoR Preparation Grant was managed by the same administrative team that oversees Nebraska's NASA Space Grant and EPSCoR programs. An advisory board (later Technical Advisory Committee) made up of voting representatives from all affiliate and partner organizations regularly reviewed grant progress and direction. The University of Nebraska at Omaha's Aviation Institute, the host institution for all three programs, provided additional administrative oversight and program evaluation through established review mechanisms. This structure has served NASA well and has been cited as a model program. The second year of preparation grant funding served as a significant opportunity for Nebraska to lay the groundwork for the continued elevation and success of its NASA EPSCoR program. In anticipation of the NASA EPSCoR 2000 grant competition, Year 2 funding enabled funded researchers to further broaden and enhance the quality and quantity of collaborations with NASA Field Centers, Codes, and Enterprises. The plan set the stage for long-term research and outreach endeavors that have contributed significantly to the achievement of NASA's strategic objectives; the state of Nebraska's economic and aerospace development efforts; and have advanced Nebraska s aeronautics research efforts to a national leadership level. The overarching goal of the NASA Nebraska EPSCoR Preparation grant was met by facilitating research endeavors among Nebraska faculty that addressed research and technology priorities of the NASA Field Centers, Codes, and Strategic Enterprises. During the first year of funding, Nebraska established open and frequent lines of communication with university affairs officers and other key personnel at all NASA Centers and Enterprises, and facilitated the development of collaborations between and among junior faculty in the state and NASA researchers. As a result, Nebraska initiated a major research cluster, the Small Aircraft Transportation System Nebraska Implementation Template.

Bowen, Brent↗
DOE OSTI2018

Minimizing Error Potential Using Computer Applications - 18498

Many Savannah River Site (SRS) liquid waste facility operations depend upon repetitive engineering calculations and operator actions. Although these calculations and actions are formalized in technical reports and paper procedures, they can still be vulnerable to data entry errors, calculation errors, equipment alignment errors, and occasional changes caused by different people performing these activities. Savannah River Remediation (SRR) is using computer automation to reduce these error precursors by standardizing repetitive calculations and by performing plant alignment checks for repetitive operation processes. Data entry can be automated, calculation methodologies can be standardized, and computers can check to see that predefined plant conditions exist before equipment operation. In addition to improving quality, the time required for these activities to generate technical reports, to perform independent reviews, and to perform equipment alignment checks can be significantly reduced. In the case of operator-performed calculations, error precursors involve distractions that can occur over a multi-page paper procedure, confusing displays and controls from equipment, mathematical errors, complacency, and unfamiliarity with the procedure among many others. Repetitive engineering calculations suffer from similar error precursors and are often compounded by high workloads, lack of proficiency, lack of standard methodology, mental shortcuts, and biases. Web-based computer applications can eliminate many of these precursors through standardization. Calculation methods are fixed, inputs are fixed, and computer checks can highlight potentially wrong inputs and outputs. Automated calculations are performed almost instantaneously once input is provided. Operators and engineers can spend more time focusing on the results than on the process to achieve the results. Similarly, when operators use repetitive procedures involving equipment manipulation, the same error precursors apply. Automated operation sequences and equipment checks can be programmed into the distributed control system to provide standard operating processes that reduce and eliminate error precursors. This paper describes how SRR incorporates Human Performance Improvement (HPI) principles when automating calculations and operation processes. Computer applications will be reviewed in detail, highlighting the software development life-cycle that includes requirements gathering, prototyping, design, development, testing, and implementation. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2012

MicroRNAs regulate osteogenesis and chondrogenesis

Highlights: Black-Right-Pointing-Pointer To focus on the role of miRNAs in chondrogenesis and osteogenesis. Black-Right-Pointing-Pointer Involved in the regulation of miRNAs in osteoarthritis. Black-Right-Pointing-Pointer To speculate some therapeutic targets for bone diseases. -- Abstract: MicroRNAs (miRNAs) are a class of small molecules and non-coding single strand RNAs that regulate gene expression at the post-transcriptional level by binding to specific sequences within target genes. miRNAs have been recognized as important regulatory factors in organism development and disease expression. Some miRNAs regulate the proliferation and differentiation of osteoblasts, osteoclasts and chondrocytes, eventually influencing metabolism and bone formation. miRNAs are expected to provide potential gene therapy targets for the clinical treatment of metabolic bone diseases and bone injuries. Here, we review the recent research progress on the regulation of miRNAs in bone biology, with a particular focus on the miRNA-mediated control mechanisms of bone and cartilage formation.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2023

(U) A General-Purpose Code for Correlated Sampling Using Batch Statistics with MCNP6 for Fixed-Source Problems

Correlated sampling can be used to reduce the uncertainty of a difference of tallies by taking advantage of the negative covariance term in the sandwich formula. Booth first showed how correlated sampling can be applied with batch statistics using MCNP’s tally fluctuation chart (TFC) to reduce the uncertainty of a difference of tallies in fixed-source problems. Booth presented a problem in which a 1273% uncertainty in a difference was reduced to 8% by accounting for correlations. Researchers He and Su recently studied correlated sampling using the TFC in MCNP version 5. They determined that the code did not print enough digits in the TFC tally means for accurate batch statistics in some cases. After modifying the source code, they concluded that “correlated sampling can yield a standard deviation of about one magnitude smaller than that predicted by the direct, un-correlated simulation when the changes in system response are small (say about 1%), which is equivalent to saving in CPU time by a factor of 100. Such saving [sic] becomes less significant as the change in system response becomes larger.” He and Su provided the formulas needed to apply batch statistics to compute the correlated uncertainty of a difference of tallies. In this report, we follow up on their work by providing the formulas needed to apply batch statistics to compute the correlated uncertainty of a ratio of tallies and of a difference of two tallies divided by a third tally. We extend these formulas to differences and ratios of ratios. These formulas are applied to reduce the uncertainty associated with calculating a relative sensitivity. He and Su did not investigate the accuracy of their correlated sampling uncertainty estimates. We use their test problems and evaluate the accuracy of the uncertainty estimates by comparing with results obtained from random sampling, and, in simple cases, with theoretical values of the “exact” uncertainties. We find that the uncertainties obtained from batch statistics are accurate as long as at least 100 batches are used. We present a new computer code, COSUBS (COrrelated Sampling Using Batch Statistics), that reads MCNP6 TFCs and applies correlated sampling using batch statistics for the tally combinations that the user specifies. COSUBS is a very general tool that compares all TFCs for a base case and one or two perturbed cases. It computes uncertainties for ratios if given only a base case. This report is organized as follows. The equations to apply batch statistics to the difference of random tallies are reviewed in Sec. II. Section III presents the equations for applying batch statistics to a ratio of random tallies; this is useful for computing relative sensitivities using a one-sided finite difference and the relative sensitivity using the differential operator method. Section IV presents the equations for applying batch statistics to a difference of two random tallies divided by a third; this is useful for computing a relative sensitivities using a central difference. Section V presents the equations for applying batch statistics to a difference of two ratios with four random tallies. Section VI presents the equations for applying batch statistics to a one-sided finite difference estimate of the relative sensitivity of a ratio (this uses four random tallies). Section VII presents the equations for applying batch statistics to a central difference estimate of the relative sensitivity of a ratio (this uses six random tallies). Section VIII presents the equations for applying batch statistics to a sum of random tallies. Section IX discusses how to apply batch statistics using MCNP6. Section X presents COSUBS, describing its command-line options and logic. Sections XI through XVI present numerical results for various test problems. Section XVII is a summary and conclusions. Appendix A derives the theoretical Monte Carlo tally variance given certain assumptions; these variances are used to verify the batch statistics for some of the problems. Appendix B lists the MCNP6 input for the unperturbed example problem. Appendix C presents modifications made to MCNP6.3 to support this work.

97 MATHEMATICS AND COMPUTING↗
NASA NTRS2004

The Office of Inspector General (OIG)

The NASA Office of Inspector General is the Federal Law Enforcement Agency at NASA which conducts criminal and regulatory investigations in which NASA is a victim. The OIG prevents and detects crime, fiaud, waste and abuse and assists NASA management in promoting economy, efficiency, and effectiveness in its programs and operations. Investigations (OI) and the Office of Audits (OA). The investigations side deals with criminal Investigations, administrative investigations, and civil investigations. The Audits side deals with inspections and assessments as well as the Auditing of NASA Programs and Activities. Our mission at the OIG is to conduct and supervise independent and objective audits and investigations relating to agency programs and operations; to promote economy, effectiveness and efficiency within the agency; to prevent and detect crime, fraud, waste and abuse in agency programs and operations; to review and make recommendations regarding existing and proposed legislation and regulations relating to agency programs and operations. We are also responsible for keeping the agency head and the Congress fully and currently informed of problems in agency programs and operations. deal with False Claims, False Statements, Conspiracy, Theft, Computer Crime, Mail Fraud, the Procurement Integrity Act, the Anti-Kickback Act, as well as noncompliance with NASA Management Instructions, the Federal Acquisition Regulations (FAR), and the Code of Federal Regulations (CFR). Most of the casework that is dealt with in our office is generated through gum shoe work or cases that we generate on our own. These cases can come from Law Enforcement Referrals, GIDEP Reports, EPlMS (NASA Quality System), Defense Contract Audit Agency, Newspaper Articles, and Confidential Information. In many cases, confidentiality is the biggest factor to informants coming forward. We are able to maintain confidentiality because the 01 is independent of NASA Management and doesn t report to the Center Directors, therefore the informant s mangers and supervisors are unaware of the informants actions. The only time when an informant s confidentiality may be compromised is when it is needed in a Court of Law and is released through a Judicial Court Order. During my tenure here at the NASA OIG/OI at Glenn Research Center, I have been involved in many different tasks. They have ranged from updating Suspected Unapproved Parts case files to independently interviewing NASA employees to turn up general background information. The 01 has the duty of informing NASA aeronautical safety managers of potential Nonconforming products. My mission is to compile a database of Nonconformance reports for distribution. The background information that I turn up from my interviews is then used to determine NASA s susceptibility to acceptance of unapproved parts. The IG organization is divided up into two separate disciplines, the Office of 01 investigations primarily focus on violations of Federal laws. Some of these violations

Macisco, Christopher A.↗
NASA NTRS2019

Helium Balloon Valve Improvement

The NASA Balloon Program Office (BPO), located at Wallops Flight Facility asked the Mechanical Systems Branch (Code 548) to improve the design of their balloon valve. BPO uses two main types of balloons, Zero Pressure Balloon (ZPB) and Super Pressure Balloon (SPB), which both use the valve. It is used for termination of the ZPB, and inflation and termination of the SPB. During launch campaigns the valve showed signs of helium leakage which lead the BPO to ask for an improvement. As part of a Professional Readiness Engineering Program (PREP), research and review of the current valve was conducted and a new design was prepared. The current custom designed valve consists of a "pie" plate that is actuated up and down via a gear rack that is driven by a globe motor. When closed the knife edge of the pie plate bites into a silicone gasket to seal the structure. Unfortunately, the gasket material permanently deforms after being compressed and the plate itself bends under the force induced by the motor, introducing two possible helium leak paths. The new custom designed valve utilizes o-rings instead of one gasket to reduce the possibility of leakage from permanent deformation. One o-ring seals the valve structure to its mating surface and a spring energized o-ring is used in a piston design to seal the valve once it's closed. The design also utilizes different materials to increase stiffness and strength so that it is less likely to bend under the force from the motor. Currently the new valve has finished the design and analysis phases and is proceeding towards manufacturing and testing.

Seo, Lindsey↗
DOE OSTI2011

ADVANCED MIXING MODELS

The process of recovering and processing High Level Waste (HLW) the waste in storage tanks at the Savannah River Site (SRS) typically requires mixing the contents of the tank with one to four mixers (pumps) located within the tank. The typical criteria to establish a mixed condition in a tank are based on the number of pumps in operation and the time duration of operation. To ensure that a mixed condition is achieved, operating times are typically set conservatively long. This approach results in high operational costs because of the long mixing times and high maintenance and repair costs for the same reason. A significant reduction in both of these costs might be realized by reducing the required mixing time based on calculating a reliable indicator of mixing with a suitably validated computer code. The focus of the present work is to establish mixing criteria applicable to miscible fluids, with an ultimate goal of addressing waste processing in HLW tanks at SRS and quantifying the mixing time required to suspend sludge particles with the submersible jet pump. A single-phase computational fluid dynamics (CFD) approach was taken for the analysis of jet flow patterns with an emphasis on the velocity decay and the turbulent flow evolution for the farfield region from the pump. Literature results for a turbulent jet flow are reviewed, since the decay of the axial jet velocity and the evolution of the jet flow patterns are important phenomena affecting sludge suspension and mixing operations. The work described in this report suggests a basis for further development of the theory leading to the identified mixing indicators, with benchmark analyses demonstrating their consistency with widely accepted correlations. Although the indicators are somewhat generic in nature, they are applied to Savannah River Site (SRS) waste tanks to provide a better, physically based estimate of the required mixing time. Waste storage tanks at SRS contain settled sludge which varies in height from zero to 10 ft. The sludge has been characterized and modeled as micron-sized solids, typically 1 to 5 microns, at weight fractions as high as 20 to 30 wt%, specific gravities to 1.4, and viscosities up to 64 cp during motion. The sludge is suspended and mixed through the use of submersible slurry jet pumps. To suspend settled sludge, water is added to the tank as a slurry medium and stirred with the jet pump. Although there is considerable technical literature on mixing and solid suspension in agitated tanks, very little literature has been published on jet mixing in a large-scale tank. One of the main objectives in the waste processing is to provide feed of a uniform slurry composition at a certain weight percentage (e.g. typically {approx}13 wt% at SRS) over an extended period of time. In preparation of the sludge for slurrying, several important questions have been raised with regard to sludge suspension and mixing of the solid suspension in the bulk of the tank: (1) How much time is required to prepare a slurry with a uniform solid composition? (2) How long will it take to suspend and mix the sludge for uniform composition in any particular waste tank? (3) What are good mixing indicators to answer the questions concerning sludge mixing stated above in a general fashion applicable to any waste tank/slurry pump geometry and fluid/sludge combination?

99 GENERAL AND MISCELLANEOUS↗
DOE OSTI2012

Verification of J-integral capability in Sierra Mechanics

A finite-deformation, massively parallel, domain J -integral has been developed in Sierra Me- chanics with specific emphasis on pressurized loadings. We review the development of the domain integral and the inclusion of terms to correct for boundary tractions. We note the syntax employed in Sierra and illustrate the choice of weight function. Details are provided regarding domain selection, erack direction, and the construction of the test function. Be- cause quality meshes are required to obtain accurate measures of the driving force, methods were developed in Cubit for creating element boundaries orthogonal to the crack front. We briefly review the new capabilities and provide guidance for mesh construction. A compre- hensive set of examples illustrate the current implementation in Sierra. Examples include straight crack fronts, curved crack fronts, and non-planar crack faces. We investigate elastic and elastic-plastic cases. The inclusion of boundary tractions is verified through a pressur- ized ellipsoidal flaw. When possible, the calculated driving forees are compared to analytical solutions. Although the J -integral is available in many commercial codes, the finite defor- mation implementation in Sierra will enable analysts to examine detailed component level models and include fracture mechanics as a tool in the Sandia design process.

Ohashi, Yuki↗
DOE OSTI2024

Data for Grogan et al. "Bringing Hydrologic Realism to Water Markets"

This data set provides model output and post-processing files required to reproduce the results, tables, and figures in the paper "Bringing Hydrologic Realism to Water Markets" by Grogan et al. (in review). Other input data used in this study includes: Lisk, M., Grogan, D., Zuidema, S., Caccese, R., Peklak, D., Zheng, J., Fisher-Vanden, K., Lammers, R., Olmstead, S., & Fowler, L. (2023). Harmonized Database of Western U.S. Water Rights (HarDWR) (Version v1) [Data set]. MSD-LIVE Data Repository. https://doi.org/10.57931/2205619 Two models were used in this study: (1) The University of New Hampshire Water Balance Model WBM, and (2) a Water Market Model. Market model code and model output post-processing code that make use of these data can be found here Model output files are: 1. WBM output files: scenario[x]_wbm_output.zip Where [x] is one of 1, 2, 2a, 3, and 3a Each zipped directory contains 7 gridded NetCDF files, each reporting the 10-year annual average value of a given variable, in units of average mm/day: File Name: wbm_indUseGross_yc.nc; Description: Water withdrawals by industry (part of the urban sector) File Name: wbm_domUseGross_yc.nc; Description: Water withdrawals by the domestic sector (part of the urban sector) File Name: wbm_irrigationGross_yc.nc; Description: Water withdrawals for agriculture File Name: wbm_irrigationExtra_yc.nc; Description: Water withdrawals from unsustainable groundwater for agriculture File Name: wbm_indUseEvap_yc.nc; Description: Consumptive water use by industry File Name: wbm_domUseEvap_yc.nc; Description: Consumptive water use by the domestic sector File Name: wbm_irrigationNet_yc.nc; Description: Consumptive water use by agriculture The file full_cell_area.nc gives the area of each grid cell in km2, which is used for converting water depth to water volume. 2. Water market model output & post processing output Folder: marketTrdSummaries/ Description: Files in this folder are used as input to code 1_WelfareCalculation_actual_trades.R. They summarize historical water right trade transactions in each state. File Name: welfare_gain_by_state_sector.csv; Description: Welfare gains by state and sector, as shown in Figure 3F. Used in code Figure3.R and produced (as a .xlsx file) by code 2_DemandCurves_simulated_trades.R File Name: welfare_data_actual.rdata; Description: welfare gains by WMA from actual historical trades, as shown in Figure 3A. This data is the output of code 1_WelfareCalculation_actual_trades.R File Name: welfare_summary_simulated.xlsx; Description: Welfare gains by state as simulated by the market model in Scenario 1. Produced by code 2_DemandCurves_simulated_trades.R, and used in code 4_WelfareCalculation.R. File Name: welfare_summary_cutoffs.xlsx; Description: Welfare gains by state as simulated by the market model in Scenario 2. Produced by code 3_DemandCurves_simulated_trades_cutoffs.R, and used in code 4_WelfareCalculation.R. File Name: welfare_summary_cutoffs_SGMS.xlsx; Description: Welfare gains by state as simulated by the market model in Scenario 2a. Produced by code 3_DemandCurves_simulated_trades_cutoffs.R, and used in code 4_WelfareCalculation.R. File Name: welfare_data_actual.rdata; Description: Spatial data, actual historical welfare gains by WMA as shown in Figure 3A. Produced by code 4_WelfareCalculation.R and used by code Figure3.R. File Name: welfare_data_simulated.rdata; Description: Spatial data, simulated Scenario 1 welfare gains by WMA as shown in Figure 3B. Produced by code 4_WelfareCalculation.R and used by code Figure3.R. File Name: welfare_data_simulated_cutoffs.rdata; Description: Spatial data, simulated Scenario 2 welfare gains by WMA. Produced by code 4_WelfareCalculation.R and used by code Figure3.R. File Name: welfare_data_simulated_cutoffs_SGMA.rdata; Description: Spatial data, simulated Scenario 2a welfare gains by WMA. Produced by code 4_WelfareCalculation.R and used by code Figure3.R. Additional files are provided for efficient reproduction of tables and figures. These include: File Name: wma_thresold_dates_Scenario2(a).csv; Description: Wet vs. paper right threshold dates for each WMA. Shown in Figure 2A,B. Produced and used by code calculate_thresolds_Figure2.R File Name: WWRTradeBounds (directory); Description: Trade boundary shapefile required to reproduce Figure 3A-D. Used in code Figure3.R File Name: welfare_region_totals.csv; Description: Welfare gains for the entire study region, as shown in Figure 3E. Used in code Figure3.R File Name: Welfare_gain_by_state_sector.csv; Description: Welfare gains by state and sector, as shown in Figure 3F. Used in code Figure3.R and produced (as a .xlsx file) by code 2_DemandCurves_simulated_trades.R File Name: WECC_MERIT_5min_v3b_mask.nc; Description: Gridded file that identified which land grid cells are in the WBM model domain, used for processing in code Figure4.py File Name: Table_1.csv; Description: All data in Table 1, reproducible from WBM output files using code table_1.R

Economics↗
NASA NTRS1974

The prebiotic synthesis of oligonucleotides

This paper is primarily a review of recent developments in the abiotic synthesis of nucleotides, short chain oligonucleotides, and their mode of replication in solution. It also presents preliminary results from this laboratory on the prebiotic synthesis of thymidine oligodeoxynucleotides. A discussion, based on the physicochemical properties of RNA and DNA oligomers, relevant to the molecular evolution of these compounds leads to the tentative hypothesis that oligodeoxyribonucleotides of about 12 units may have been of sufficient length to initiate a self replicating coding system. Two models are suggested to account for the synthesis of high molecular weight oligomers using short chain templates and primers.

Oro, J.↗
NASA NTRS1991

Transport methods and interactions for space radiations

A review of the program in space radiation protection at the Langley Research Center is given. The relevant Boltzmann equations are given with a discussion of approximation procedures for space applications. The interaction coefficients are related to solution of the many-body Schroedinger equation with nuclear and electromagnetic forces. Various solution techniques are discussed to obtain relevant interaction cross sections with extensive comparison with experiments. Solution techniques for the Boltzmann equations are discussed in detail. Transport computer code validation is discussed through analytical benchmarking, comparison with other codes, comparison with laboratory experiments and measurements in space. Applications to lunar and Mars missions are discussed.

Wilson, John W.↗
NASA NTRS1999

Performance of the MIR Cooperative Solar Array After 2.5 Years in Orbit

The Mir Cooperative Solar Array (MCSA) was developed jointly by the United States and Russia to produce 6 kW of power for the Russian space station Mir. Four, multi-orbit test sequences were executed between June 1996 and December 1998 to measure MCSA electrical performance. A dedicated Fortran computer code was developed to analyze the detailed thermal-electrical performance of the MCSA. The computational performance results compared very favorably with the measured flight data in most cases. Minor performance degradation was detected in one current generating section of the MCSA. Yet overall, the flight data indicated the MCSA was meeting and exceeding performance expectations. There was no precipitous performance loss due to contamination or other causes after 2.5 years of operation. In this paper, we review the MCSA flight electrical performance tests, data and computational modeling and discuss findings from data comparisons with the computational results.

Kerslake, Thomas W.↗