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DOE OSTI2023

Impacts of Modern IT on LCLS-II Experiment Control Systems

Modern information technology (IT) is a broad term with vague and somewhat arbitrary boundaries which can depend on any given novice or subject matter expert’s notional understanding. For the purposes of this article, IT can be understood as standards in communication, computational power, and storage. Additionally, impacts of modern IT extend beyond its products of hardware and software to include associated work practices and engineering processes.

97 MATHEMATICS AND COMPUTING↗

DOE OSTI2025

On-lattice kinetic Monte Carlo approaches for modeling molecular anisotropy in resveratrol crystallization

Stilbenes are a class of organic compounds with broad-ranging pharmaceutical and agricultural applications, which are typically isolated and purified through recrystallization. We are motivated by reducing experimental waste and optimizing yield via developing predictive simulations for processing-dependent crystal morphologies. Using resveratrol as a model stilbene system, we have developed an approach for simulating crystallization with molecular resolution using on-lattice kinetic Monte Carlo. In this work, we highlight modifications to the Stochastic Parallel PARticle Kinetic Simulator (SPPARKS) software package, which were essential to this application. Key enhancements include the incorporation of non-orthogonal cell shapes and monomer anisotropy approximations using bound hard spheres. This new SPPARKS application has been applied to resveratrol with attachment energy libraries obtained from density functional theory, resulting in excellent agreement with experimental morphology prediction.

crystallization↗

DOE OSTI2023

Preliminary Nuclear Containment Vessel Modeling for Multi-Hazard Probabilistic Risk Assessment under Seismic Hazards and Concrete Degradation

The current practice for natural phenomena hazards (NPH) risk assessment of nuclear facilities is to compute the risk for each hazard independently and then compound the total risk as a combination of single hazard risks. This state of practice does not consider correlations between hazards and the cascading impacts to structures, systems, and components (SSCs), and could thus underestimate the NPH risk or overestimate the nuclear facility safety. Events such as the Fukushima Daiichi accident have highlighted the importance of multi-hazard risk considerations to nuclear power plants (NPPs) that quantify the cascading damage effects to SSCs in the risk models. Moreover, the current fleet of NPPs in the United States is aging; these NPPs are now expected to operate well beyond their initially planned design life. Aging-related deterioration can potentially decrease the capacity of critical structures such as containment vessels to withstand NPH. Such aging considerations may not be adequately accounted for by the current NPH risk assessment guidelines. This paper presents a preliminary modeling and simulation of a representative reinforced concrete containment vessel subjected to seismic mainshock and aftershock considering concrete degradation due to alkali silica reaction. The broader aim is to develop multi-hazard time-dependent fragility functions that could be subsequently used in the probabilistic risk assessment (PRA) model. The multi-hazard component comes into play due to the consideration of damage to the containment vessel under seismic loads and concrete degradation. Consideration of concrete degradation also brings into play the time-dependent nature of the containment vessel response. The response of the containment vessel under varying degrees of concrete degradation to seismic loads is investigated. The results presented are simulated using the Multi-hazard Analysis for STOchastic time-DOmaiN phenomena (MASTODON) software for seismic analysis and the Blackbear software for concrete degradation and damage modeling. Both software are open source and developed within the Multiphysics Object-Oriented Simulation Environment (MOOSE).

42 ENGINEERING↗

DOE OSTI2018

Performance Evaluation of the CHKED Multi-Elemental Analysis and Software

The Hybrid K-edge Densitometer (HKED) is a high precision safeguards assay system developed by Ottmar and Eberle [1] for quantification of the U and Pu concentrations of dissolver solutions in spent nuclear fuel reprocessing. The HKED measurement supplements traditional destructive assay methods such as Isotope Dilution Mass Spectrometry (IDMS) and is an essential component of the international safeguards program implementation at these facilities. The Canberra Hybrid K-Edge Densitometry (CHKED) software was recently developed by Canberra Industries to better address the changing composition of the nuclear fuel cycle by addition of a multi-elemental analysis capability to the K-Edge transmission measurement. Our evaluation of the CHKED software was performed at the request of the International Atomic Energy Agency (IAEA) to examine the functionality and performance of the CHKED software and algorithms and identify potential areas for improvement of the software. The reader is assumed to be familiar with the HKED technique and its current implementation in safeguards assay of U and Pu in the nuclear fuel cycle. The Canberra Hybrid K-Edge Densitometry CHKED software replicates functionality of the older VMSbased Hybrid K-Edge Densitometer (HKED) software and incorporates additional analysis algorithms and tools. When the traditional HKED analyses are selected, the CHKED software appears to faithfully reproduce the measurement results as reported by the older software. The CHKED software includes a Multi-elemental K-Edge (MEKED) analysis based in part on algorithms devised at Los Alamos National Laboratory. In principle, the MEKED analysis represents a significant advancement over the traditional HKED analysis, providing a capability to analyze the actinide concentrations from complex solutions, such as low U:Pu ratios (e.g., U:Pu = 1:1) including additional minor actinide components such as Np and Am. However, this MEKED analysis is somewhat limited by reliance on a region of interest (ROI) analysis of the spectrum, the need for extensive calibration measurements and a simplistic interpretation of the KED transmission spectrum. Finally, the MEKED algorithm set associated with the CHKED software (V1.0) acquired by Oak Ridge National Laboratory (ORNL) from Canberra Industries does not seem to be “finished” (e.g., the MEKED analysis seems to only determine measurement results for two actinides with while results for the minor actinides appear to be highly dependent on declaration values).

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗

DOE OSTI2020

Treatment of Tilted Sonar Data for Salt Cavern Analysis

Structural modeling and visualization of salt caverns requires three-dimensional representations. These representations are typically produced from sonar surveys conducted by companies that then produce a report of depths, distances, and volumes. There are multiple formats that are vendor dependent, and, as technology improves, there have been changes from only horizontal surveys to inclined shots for ceilings and floors to mid-cavern inclined shots. For geomechanical modeling, leaching predictions, and cavern stability visualizations, Sandia has previously written in-house software, called SONAR8, that created a consistent geometry format from the processed sonar reports. However, the increase in the need for mid-cavern inclined surveys led to the discovery of certain limitations in that code. This report describes methods used to process the multiple different formats to handle inclined shots in a consistent and accurate manner in our modeling efforts. A set of file formats and a database schema that was developed for this work is also documented in the appendices.

02 PETROLEUM↗

DOE OSTI2021

Corrosion Detection LDRD Seedling (Final Report)

Automation techniques for recognizing material defects are very common in fields like infrastructure survey and civil engineering; however, the defects are usually easily distinguishable from their background, on a larger scale (e.g. cement bridges), and very specific. Extracting information about a defect that is near or equal to the background of the data can be extremely difficult. Images with heavy background corrosion, pitting, cracking, and man-made defects (such as welding) makes extracting information on a specific defect near-impossible. This is especially true when the defect is on the micron level and the dynamic range of your image taking instrument is low. So, a simplified, Java-based Fiji™ (ImageJ) defect detection program, dependent on a ‘flag’ system, was proposed for data that has a micron level hairline crack that is near or equal to the background. The utilization of the built-in functions, plugins, and macro scripting capability of the Java-based software sends a series of flags to the user that help to identify if the surface contains a defect of interest and to characterize that defect.

42 ENGINEERING↗

NASA NTRS1974

HAL/S-FC compiler system functional specification

The functional requirements to be met by the HAL/S-FC compiler, and the hardware and software compatibilities between the compiler system and the environment in which it operates are defined. Associated runtime facilities and the interface with the Software Development Laboratory are specified. The construction of the HAL/S-FC system as functionally separate units and the interfaces between those units is described. An overview of the system's capabilities is presented and the hardware/operating system requirements are specified. The computer-dependent aspects of the HAL/S-FC are also specified. Compiler directives are included.

Source record↗

NASA NTRS1997

High Speed CCD Photometry of the P/Shoemaker-Levy 9-Jupiter Collision

Using the National Solar Observatory 64-inch Vacuum Tower Telescope at Sacramento Peak, we have obtained high spatial and time resolution images of Jupiter in the visible continuum at 5000 A, in the 7250 A and 8900 A methane bands, plus their adjacent continuum bands (at 7500 A and 9500 A), before, during, and after the times of the collisions. In addition, with the use of a beam splitter, near-IR images (J-band) were also obtained simultaneously with a 256 x 256 NICMOS chip. The observations spanned the time period 14 - 25 July 1994, at intervals of several hours each day, depending on the weather and the visibility of Jupiter. The original proposal was to use the data to track the evolution of the impact clouds produced by impacts from comet Shoemaker-Levy 9. We are still refining the automated data analysis software and finalizing the calibration of the images. The latter is an arduous problem since many of the images were made in daylight. We expect to finish these two tasks in early 1998, whereupon the analysis will proceed very quickly. Our goals remain unchanged. We will use lightcurves of the impact sites for the following goals: (1) to monitor and understand the time variability of the optical depths of the impact clouds; (2) to monitor and understand the time variability of the masses of the impact clouds; (3) to monitor the wind speeds in the upper atmosphere of Jupiter.

Source record↗

NASA NTRS2010

Reference Avionics Architecture for Lunar Surface Systems

Developing and delivering infrastructure capable of supporting long-term manned operations to the lunar surface has been a primary objective of the Constellation Program in the Exploration Systems Mission Directorate. Several concepts have been developed related to development and deployment lunar exploration vehicles and assets that provide critical functionality such as transportation, habitation, and communication, to name a few. Together, these systems perform complex safety-critical functions, largely dependent on avionics for control and behavior of system functions. These functions are implemented using interchangeable, modular avionics designed for lunar transit and lunar surface deployment. Systems are optimized towards reuse and commonality of form and interface and can be configured via software or component integration for special purpose applications. There are two core concepts in the reference avionics architecture described in this report. The first concept uses distributed, smart systems to manage complexity, simplify integration, and facilitate commonality. The second core concept is to employ extensive commonality between elements and subsystems. These two concepts are used in the context of developing reference designs for many lunar surface exploration vehicles and elements. These concepts are repeated constantly as architectural patterns in a conceptual architectural framework. This report describes the use of these architectural patterns in a reference avionics architecture for Lunar surface systems elements.

Somervill, Kevin M.↗

NASA NTRS2012

Optical Navigation Preparations for New Horizons Pluto Flyby

The New Horizons spacecraft will encounter Pluto and its satellites in July 2015. As was the case for the Voyager encounters with Jupiter, Saturn, Uranus and Neptune, mission success will depend heavily on accurate spacecraft navigation, and accurate navigation will be impossible without the use of pictures of the Pluto system taken by the onboard cameras. We describe the preparations made by the New Horizons optical navigators: picture planning, image processing algorithms, software development and testing, and results from in-flight imaging.

image processing↗

NASA NTRS2015

Reconfigurable Very Long Instruction Word (VLIW) Processor

Future NASA missions will depend on radiation-hardened, power-efficient processing systems-on-a-chip (SOCs) that consist of a range of processor cores custom tailored for space applications. Aries Design Automation, LLC, has developed a processing SOC that is optimized for software-defined radio (SDR) uses. The innovation implements the Institute of Electrical and Electronics Engineers (IEEE) RazorII voltage management technique, a microarchitectural mechanism that allows processor cores to self-monitor, self-analyze, and selfheal after timing errors, regardless of their cause (e.g., radiation; chip aging; variations in the voltage, frequency, temperature, or manufacturing process). This highly automated SOC can also execute legacy PowerPC 750 binary code instruction set architecture (ISA), which is used in the flight-control computers of many previous NASA space missions. In developing this innovation, Aries Design Automation has made significant contributions to the fields of formal verification of complex pipelined microprocessors and Boolean satisfiability (SAT) and has developed highly efficient electronic design automation tools that hold promise for future developments.

Velev, Miroslav N.↗

NASA NTRS1992

Development of the FITS tools package for multiple software environments

The HEASARC is developing a package of general purpose software for analyzing data files in FITS format. This paper describes the design philosophy which makes the software both machine-independent (it runs on VAXs, Suns, and DEC-stations) and software environment-independent. Currently the software can be compiled and linked to produce IRAF tasks, or alternatively, the same source code can be used to generate stand-alone tasks using one of two implementations of a user-parameter interface library. The machine independence of the software is achieved by writing the source code in ANSI standard Fortran or C, using the machine-independent FITSIO subroutine interface for all data file I/O, and using a standard user-parameter subroutine interface for all user I/O. The latter interface is based on the Fortran IRAF Parameter File interface developed at STScI. The IRAF tasks are built by linking to the IRAF implementation of this parameter interface library. Two other implementations of this parameter interface library, which have no IRAF dependencies, are now available which can be used to generate stand-alone executable tasks. These stand-alone tasks can simply be executed from the machine operating system prompt either by supplying all the task parameters on the command line or by entering the task name after which the user will be prompted for any required parameters. A first release of this FTOOLS package is now publicly available. The currently available tasks are described, along with instructions on how to obtain a copy of the software.

Pence, W. D.↗

DOE OSTI2021

Cartesian message passing neural networks for directional properties: Fast and transferable atomic multipoles

The message passing neural network (MPNN) framework is a promising tool for modeling atomic properties but is, until recently, incompatible with directional properties, such as Cartesian tensors. We propose a modified Cartesian MPNN (CMPNN) suitable for predicting atom-centered multipoles, an essential component of ab initio force fields. The efficacy of this model is demonstrated on a newly developed dataset consisting of 46 623 chemical structures and corresponding high-quality atomic multipoles, which was deposited into the publicly available Molecular Sciences Software Institute QCArchive server. We show that the CMPNN accurately predicts atom-centered charges, dipoles, and quadrupoles and that errors in the predicted atomic multipoles have a negligible effect on multipole–multipole electrostatic energies. The CMPNN is accurate enough to model conformational dependencies of a molecule’s electronic structure. This opens up the possibility of recomputing atomic multipoles on the fly throughout a simulation in which they might exhibit strong conformational dependence.

Glick, Zachary L. (ORCID:0000000309002849)↗

DOE OSTI2017

Study of the distribution profile of iron ions implanted into silicon

Iron ions with energies of 90 and 250 keV and a dose of 10{sup 16} cm{sup –2} are implanted into a silicon single crystal with the (110) orientation. The method of Rutherford backscattering in combination with channeling is used to study the distribution profiles of the introduced impurity and also the profiles of the distribution of radiation-induced defects in the crystal lattice. Experimental data are compared with the results of simulation performed using the TRIM software package. It is shown that, at an energy of 4.6 keV/nucleon, the average projected ranges coincide; however, at an energy of 1.6 keV/nucleon, the difference amounts to 35%. In addition, it is shown that the calculation incorrectly takes into account the dose dependence at energies of 1.6–4.6 keV/nucleon.

36 MATERIALS SCIENCE↗

DOE OSTI2019

Porotomo: InSAR Data from San Emidio Geothermal Field, Nevada, 1992-2010

This submission contains tarred pair directories for interferometric synthetic aperture radar (InSAR) data covering San Emidio Geothermal Field in Nevada, USA as part of the porotomo project. Data included within this submission are the following: > ENVI_T120_GDR.tgz: Tarred directory containing 39 Envisat track 120 tarred, pair subdirectories spanning from 2003-Oct-29 to 2010-Jun-09. > ENVI_T27_GDR.tgz: Tarred directory containing 32 Envisat track 27 tarred, pair subdirectories spanning from 2004-Jun-23 to 2010-Apr-28. > ERS_T27_GDR.tgz: Tarred directory containing 35 ERS track 27 tarred, pair subdirectories spanning from 1992-Jun-07 to 2000-Sep-27. > ENVI_T27_SQR_drange_utm_cut.grd: SqueeSAR-derived data product for Enivsat track 27 from Eneva, et al. (2011) (provided by TRE Altamira) in terms of unwrapped range change rate. > MSTvsSQR_GDR.tgz: Tarred directory containing Easting gradient files for each satellite and track corresponding to the MST data products and the SqueeSAR data products. > sanem_dem_utm.grd: Digital elevation model (DEM) used in the creation of the interferograms. Explanation of pair subdirectories (contained within ENVI_T120_GDR, ENVI_T27_GDR, ERS_T27_GDR): Pairs are chosen based on a minimum spanning tree (MST) algorithm with image quality (as measured by the amount of phase noise within an interferometric pair) as the weighting criterion. Pairs are formed using the InSAR processing software GMT5SAR (Sandwell et al., 2011). Pair subdirectories are named by starting and ending epochs in YYYYMMDD_YYYYMMDD format. Each tarred pair directory contains GRD files for wrapped phase data (radians) and wrapped phase data after application of a modified Goldstein filter that depends on coherence (Goldstein & Werner, 1997; Baran et al., 2003; Sandwell et al., 2011). The data are given in both latitude/longitude and Universal Transverse Mercator (Zone 11N). Raw Synthetic Aperture Radar (SAR) data from the Envisat and ERS satellite missions operated by the European Space Agency (ESA) are copyrighted by ESA and were provided through the WInSAR consortium at the UNAVCO facility.

15 GEOTHERMAL ENERGY↗

DOE OSTI2020

Discrete Element Method Analysis for Metal Powders Used in Additive Manufacturing, and DEM Simulation Tutorial Using LIGGGHTS-PUBLIC [PowerPoint and paper]

Discrete Element Method (DEM) is a method of analysis to evaluate the dynamic interactions between granular particles. This method has been used in the pharmaceutical industry to improve the powder compaction process for tablet manufacturing. There are also applications in agriculture, food industry, and manufacturing. Direct energy deposition is an additive manufacturing technique which uses metallic powders fed through a nozzle, melted using a directed laser, and transformed into a solid object layer by layer. One way of feeding metal particles into the system involves the use of a vibrating hopper. Given a specified amplitude and frequency input, the hopper will enable the powder to travel up a path, and inject through the system with assistance from a stream of gas. The mechanical properties of a printed object can vary, depending on the characteristics of the powder flow and the particles’ as-received properties. Improved understanding of dynamic interactions of flowing powders could enable additive manufacturing components with 2D or 3D variations in mechanical properties, e.g., density. This work uses DEM simulation software to investigate the effects of particle cohesion, friction, and density on the quality of the flow by performing an angle of repose simulation, which is often used as a metric to evaluate the flowability of powders.

36 MATERIALS SCIENCE↗

DOE OSTI2017

MerCat: a versatile k-mer counter and diversity estimator for database-independent property analysis obtained from metagenomic and/or metatranscriptomic sequencing data

MerCat is a parallel, highly scalable and modular property software package for robust analysis of features in next-generation sequencing data. MerCat inputs include assembled contigs and raw sequence reads from any platform resulting in feature abundance counts tables. MerCat allows for direct analysis of data properties without reference sequence database dependency commonly used by search tools such as BLAST and/or DIAMOND for compositional analysis of whole community shotgun sequencing (e.g. metagenomes and metatranscriptomes).

metabolomics↗

NASA NTRS1992

Data analysis of the COMPTEL instrument on the NASA gamma ray observatory

The Compton imaging telescope (COMPTEL) on the Gamma Ray Observatory (GRO) is a wide field of view instrument. The coincidence measurement technique in two scintillation detector layers requires specific analysis methods. Straightforward event projection into the sky is impossible. Therefore, detector events are analyzed in a multi-dimensional dataspace using a gamma ray sky hypothesis convolved with the point spread function of the instrument in this dataspace. Background suppression and analysis techniques have important implications on the gamma ray source results for this background limited telescope. The COMPTEL collaboration applies a software system of analysis utilities, organized around a database management system. The use of this system for the assistance of guest investigators at the various collaboration sites and external sites is foreseen and allows different detail levels of cooperation with the COMPTEL institutes, dependent on the type of data to be studied.

Diehl, R.↗