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

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At least 865 records · Page 48
All sourcesNASA NTRSDOE OSTI
NASA NTRS2000

Accelerated thermal and mechanical testing of CSP assemblies

Chip Scale Packages (CSP) are now widely used for many electronic applications including portable and telecommunication products. A test vehicle (TV-1) with eleven package types and pitches was built and tested by the JPL MicrotypeBGA Consortium during 1997 to 1999. Lessons learned by the team were published as a guidelines document for industry use. The finer pitch CSP packages which recently became available were indluded in the next test vehicle of the JPL CSP Consortium.

Chip Scale Package CSP thermal cycle fatigue solde↗
NASA NTRS2006

Cold Flow Testing for Liquid Propellant Rocket Injector Scaling and Throttling

Scaling and throttling of combustion devices are important capabilities to demonstrate in development of liquid rocket engines for NASA's Space Exploration Mission. Scaling provides the ability to design new injectors and injection elements with predictable performance on the basis of test experience with existing injectors and elements, and could be a key aspect of future development programs. Throttling is the reduction of thrust with fixed designs and is a critical requirement in lunar and other planetary landing missions. A task in the Constellation University Institutes Program (CUIP) has been designed to evaluate spray characteristics when liquid propellant rocket engine injectors are scaled and throttled. The specific objectives of the present study are to characterize injection and primary atomization using cold flow simulations of the reacting sprays. These simulations can provide relevant information because the injection and primary atomization are believed to be the spray processes least affected by the propellant reaction. Cold flow studies also provide acceptable test conditions for a university environment. Three geometric scales - 1/4- scale, 1/2-scale, and full-scale - of two different injector element types - swirl coaxial and shear coaxial - will be designed, fabricated, and tested. A literature review is currently being conducted to revisit and compile the previous scaling documentation. Because it is simple to perform, throttling will also be examined in the present work by measuring primary atomization characteristics as the mass flow rate and pressure drop of the six injector element concepts are reduced, with corresponding changes in chamber backpressure. Simulants will include water and gaseous nitrogen, and an optically accessible chamber will be used for visual and laser-based diagnostics. The chamber will include curtain flow capability to repress recirculation, and additional gas injection to provide independent control of the backpressure. This paper provides a short review of the appropriate literature, as well as descriptions of plans for experimental hardware, test chamber instrumentation, diagnostics, and testing.

Kenny, Jeremy R.↗
NASA NTRS2015

Human Performance Considerations for Remotely Piloted Aircraft Systems (RPAS)

Successful integration of Remotely Piloted Aircraft Systems (RPAS) into civil airspace will not only require solutions to technical challenges, but will also require that the design and operation of RPAS take into account human limitations and capabilities. Human factors can affect overall system performance whenever the system relies on people to interact with another element of the system. Four types of broad interactions can be described. These are (1) interactions between people and hardware, such as controls and displays; (2) human use of procedures and documentation; (3) impact of the task environment, including lighting, noise and monotony; and lastly, (4) interactions between operational personnel, including communication and coordination. In addition to the human factors that have been identified for conventional aviation, RPAS operations introduce a set of unique human challenges. The purpose of document is to raise human factors issues for consideration by workgroups of the ICAO RPAS panel as they work to develop guidance material and additions to ICAO annexes. It is anticipated that the content of this document will be revised and updated as the work of the panel progresses.

ICAO↗
NASA NTRS2012

Environmentally Friendly Corrosion Preventative Compounds

The objective of the Ground Systems Development and Operations Program Environmentally Friendly Corrosion Protective Coatings and Corrosion Preventive Compounds (CPCs) project is to identify, test, and develop qualification criteria for the use of environmentally friendly corrosion protective coatings and CPCs for flight hardware and ground support equipment. This document is the Final Report for Phase I evaluations, which included physical property, corrosion resistance, and NASA spaceport environment compatibility testing and analysis of fifteen CPC types. The CPCs consisted of ten different oily film CPCs and five different wax or grease CPC types. Physical property testing encompassed measuring various properties of the bulk CPCs, while corrosion resistance testing directly measured the ability of each CPC material to protect various metals against corrosion. The NASA spaceport environment compatibility testing included common tests required by NASA-STD-6001, "Flammability, Odor, Offgassing, and Compatibility Requirements and Test Procedures for Materials in Environments that Support Combustion". At the end of Phase I, CPC materials were down-selected for inclusion in the next test phases. This final report includes all data and analysis of results obtained by following the experimental test plan that was developed as part of the project. Highlights of the results are summarized by test criteria type.

Preventative Compounds↗
DOE OSTI2019

The 2019 Edition of the ICSBEP Handbook

Over the past several decades, innumerable experiments have been performed worldwide to support criticality safety. These experiments represent significant investment in infrastructure, expertise, and cost, and are valuable resources of data for present and future research. These valuable assets provide the basis for recording, development, and validation of methods and nuclear data [1]. If the experimental data are lost, the high cost to repeat many of these measurements would likely be prohibitive. The International Criticality Safety Benchmark Evaluation Project (ICSBEP) was established to: 1. Identify a comprehensive set of critical benchmark data and, to the extent possible, verify the data; 2. Evaluate the data and quantify overall uncertainties through various types of sensitivity analyses; 3. Compile the data into a standardized format; 4. Perform calculations of each experiment with standard criticality safety codes; and 5. Formally document the work into a single source of verified benchmark critical data. Annually, contributors from around the world continue to collaborate in the evaluation and review of select benchmark experiments for inclusion in the International Handbook of Evaluated Criticality Safety Benchmark Experiments (ICSBEP Handbook) [2]. Further information regarding the ICSBEP, including highlighted criticality safety benchmark evaluations, can be found in the September and October 2003 editions of Nuclear Science and Engineering [3]. New and recently revised evaluations have been prepared for inclusion in the 2019 edition of the ICSBEP Handbook.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
DOE OSTI2013

Alternative Endpoints and Approaches for the Remediation of Contaminated Groundwater at Complex Sites - 13426

The goal of United States (U.S.) Department of Energy's (DOE)'s environmental remediation programs is to restore groundwater to beneficial use, similar to many other Federal and state environmental cleanup programs. Based on past experience, groundwater remediation to pre-contamination conditions (i.e., drinking water standards or non-detectable concentrations) can be successfully achieved at many sites. At a subset of the most complex sites, however, complete restoration is not likely achievable within the next 50 to 100 years using today's technology. This presentation describes several approaches used at complex sites in the face of these technical challenges. Many complex sites adopted a long-term management approach, whereby contamination was contained within a specified area using active or passive remediation techniques. Consistent with the requirements of their respective environmental cleanup programs, several complex sites selected land use restrictions and used risk management approaches to accordingly adopt alternative cleanup goals (alternative endpoints). Several sites used long-term management designations and approaches in conjunction with the alternative endpoints. Examples include various state designations for groundwater management zones, technical impracticability (TI) waivers or greater risk waivers at Superfund sites, and the use of Monitored Natural Attenuation (MNA) or other passive long-term management approaches over long time frames. This presentation will focus on findings, statistics, and case studies from a recently-completed report for the Department of Defense's Environmental Security Technology Certification Program (ESTCP) (Project ER-0832) on alternative endpoints and approaches for groundwater remediation at complex sites under a variety of Federal and state cleanup programs. The primary objective of the project was to provide environmental managers and regulators with tools, metrics, and information needed to evaluate alternative endpoints for groundwater remediation at complex sites. A statistical analysis of Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) sites receiving TI waivers will be presented as well as case studies of other types of alternative endpoints and alternative remedial strategies that illustrate the variety of approaches used at complex sites and the technical analyses used to predict and document cost, time frame, and potential remedial effectiveness. This presentation is intended to inform DOE program managers, state regulators, practitioners and other stakeholders who are evaluating technical cleanup challenges within their own programs, and establishing programmatic approaches to evaluating and implementing long-term management approaches. Case studies provide examples of long-term management designations and strategies to manage and remediate groundwater at complex sites. At least 13 states consider some designation for groundwater containment in their corrective action policies, such as groundwater management zones, containment zones, and groundwater classification exemption areas. Long-term management designations are not a way to 'do nothing' or walk away from a site. Instead, soil and groundwater within the zone is managed to be protective of human health and the environment. Understanding when and how to adopt a long-term management approach can lead to cost savings and the more efficient use of resources across DOE and at numerous other industrial and military sites across the U.S. This presentation provides context for assessing the use and appropriate role of alternative endpoints and supporting long-term management designations in final remedies. (authors)

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2015

Automation of environmental compliance data acquisition and management - 15267

Regulatory sampling for environmental compliance at the Savannah River Site (SRS), Aiken, South Carolina employs several different types of sampling techniques at various sampling frequencies. These sampling events result in the collection of large quantities of data and generate substantial data-related documents. The use of paper documents resulted in the need for manual input of data collected in the field and distribution of documents from one group to the next. To efficiently and effectively manage the extensive amounts of data and documents, elements of the sampling process were automated using hand-held field tablets and an electronic application. The tablets allow for easier distribution of sampling documents, and the application allows for digital transfer of sampling information and collected field data. The transition to automated data acquisition and management has resulted in a more efficient and reliable manner for conducting business at SRS. This system benefits numerous organizations at SRS by utilizing a centralized database for efficient management of all environmental data collected. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2016

The 2016 Edition of the ICSBEP Handbook

Over the past several decades, numerous experiments have been performed worldwide to support criticality safety. These experiments represent a significant investment in infrastructure, expertise, and cost, and are valuable resources of data for present and future research. These valuable assets provide the basis for recording, development, and validation of methods and nuclear data. If the experimental data are lost, the high cost to repeat many of these measurements may be prohibitive. The International Criticality Safety Benchmark Evaluation Project (ICSBEP) was established to: 1. Identify a comprehensive set of critical benchmark data and, to the extent possible, verify the data; 2. Evaluate the data and quantify overall uncertainties through various types of sensitivity analyses; 3. Compile the data into a standardized format; 4. Perform calculations of each experiment with standard criticality safety codes; and 5. Formally document the work into a single source of verified benchmark critical data. Annually, contributors from around the world continue to collaborate in the evaluation and review of select benchmark experiments for inclusion in the International Handbook of Evaluated Criticality Safety Benchmark Experiments (ICSBEP Handbook). Further information regarding the ICSBEP, including highlighted criticality safety benchmark evaluations, can be found in the September and October 2003 editions of Nuclear Science and Engineering. Several new evaluations have been prepared for inclusion in the September 2016 edition of the ICSBEP Handbook. (authors)

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
NASA NTRS1998

Photogrammetric Assessment of the Hubble Space Telescope Solar Arrays During the Second Servicing Mission

This report documents the photogrammetric assessment of the Hubble Space Telescope (HST) solar arrays conducted by the NASA c Center Image Science and Analysis Group during Second Servicing Mission 2 (SM-2) on STS-82 in February 1997. Two type solar array analyses were conducted during the mission using Space Shuttle payload bay video: (1) measurement of solar array motion due to induced loads, and (2) measurement of the solar array static or geometric twist caused by the cumulative array loading. The report describes pre-mission planning and analysis technique development activities conducted to acquire and analyze solar array imagery data during SM-2. This includes analysis of array motion obtained during SM-1 as a proof-of-concept of the SM-2 measurement techniques. The report documents the results of real-time analysis conducted during the mission and subsequent analysis conducted post-flight. This report also provides a summary of lessons learned on solar array imagery analysis from SM-2 and recommendations for future on-orbit measurements applicable to HST SM-3 and to the International Space Station. This work was performed under the direction of the Goddard Space Flight Center HST Flight Systems and Servicing Project.

Sapp, C. A.↗
NASA NTRS1993

Long Duration Exposure Facility (LDEF) experiment M0003 meteoroid and debris survey

A survey of the meteoroid and space debris impacts on LDEF experiment M0003 was performed. The purpose of this survey was to document significant impact phenomenology and to obtain impact crater data for comparison to current space debris and micrometeoroid models. The survey consists of the following: photomicrographs of significant impacts in a variety of material types; accurate measurements of impact crater coordinates and dimensions for selected experiment surfaces; and databasing of the crater data for reduction, manipulation, and comparison to models. Large area surfaces that were studied include the experiment power and data system (EPDS) sunshields, environment exposure control canister (EECC) sunshields, and the M0003 signal conditioning unit (SCU) covers. Crater diameters down to 25 microns were measured and cataloged. Both leading (D8) and trailing (D4) edge surfaces were studied and compared. The EPDS sunshields are aluminum panels painted with Chemglaze A-276 white thermal control paint, the EECC sunshields are chromic acid-anodized aluminum, and the SCU covers are aluminum painted with S13GLO white thermal control paint. Typical materials that have documented impacts are metals, glasses and ceramics, composites, polymers, electronic materials, and paints. The results of this survey demonstrate the different response of materials to hypervelocity impacts. Comparison of the survey data to curves derived from the Kessler debris model and the Cour-Palais micrometeoroid model indicates that these models overpredict small impacts (less than 100 micron) and may underpredict large impacts (greater than 1000 micron) while having fair to good agreement for the intermediate impacts. Comparison of the impact distributions among the various surfaces indicates significant variations, which may be a function of material response effects, or in some cases surface roughness. Representative photographs and summary graphs of the impact data are presented.

Meshishnek, M. J.↗
DOE OSTI2012

GUIDANCE FOR THE PROPER CHARACTERIZATION AND CLASSIFICATION OF LOW SPECIFIC ACTIVITY MATERIALS AND SURFACE CONTAMINATED OBJECTS FOR DISPOSAL

Regulatory concerns over the proper characterization of certain waste streams led CH2M HILL Plateau Remediation Company (CHPRC) to develop written guidance for personnel involved in Decontamination & Decommissioning (D&D) activities, facility management and Waste Management Representatives (WMRs) involved in the designation of wastes for disposal on and off the Hanford Site. It is essential that these waste streams regularly encountered in D&D operations are properly designated, characterized and classified prior to shipment to a Treatment, Storage or Disposal Facility (TSDF). Shipments of waste determined by the classification process as Low Specific Activity (LSA) or Surface Contaminated Objects (SCO) must also be compliant with all applicable U.S. Department of Transportation (DOE) regulations as well as Department of Energy (DOE) orders. The compliant shipment of these waste commodities is critical to the Hanford Central Plateau cleanup mission. Due to previous problems and concerns from DOE assessments, CHPRC internal critiques as well as DOT, a management decision was made to develop written guidance and procedures to assist CHPRC shippers and facility personnel in the proper classification of D&D waste materials as either LSA or SCO. The guidance provides a uniform methodology for the collection and documentation required to effectively characterize, classify and identify candidate materials for shipping operations. A primary focus is to ensure that waste materials generated from D&D and facility operations are compliant with the DOT regulations when packaged for shipment. At times this can be difficult as the current DOT regulations relative to the shipment of LSA and SCO materials are often not clear to waste generators. Guidance is often sought from NUREG 1608/RAMREG-003 [3]: a guidance document that was jointly developed by the DOT and the Nuclear Regulatory Commission (NRC) and published in 1998. However, NUREG 1608 [3] is now thirteen years old and requires updating to comply with the newer DOT regulations. Similar challenges present themselves throughout the nuclear industry in both commercial and government operations and therefore, this is not only a Hanford Site problem. Shipping radioactive wastes as either LSA or SCO rather than repacking it is significantly cheaper than other DOT radioactive materials shipping classifications particularly when the cost of packages is included. Additionally, the need to 'repackage' materials for transport can often increase worker exposure, necessitated by 'repackaging' waste materials into DOT 7 A Type A containers.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2015

X-Ray Diffraction of Slag-Based Sodium Salt Waste Forms - 15513

Cementitious materials are used to solidify and stabilize aqueous based radioactive waste containing sodium salts. The types and proportions of cementitious ingredients used to treat aqueous radioactive waste streams containing sodium salts depend on the performance objectives for the waste forms and the compositions of the waste streams. This paper documents sample preparation and x-ray diffraction results for a series of materials made with water or highly alkaline sodium salt simulated waste water and cementitious binders. The objective of this study was to: 1) generate a base line for the evolution of the waste form as a function of time and conditions, 2) design new binders based on mineralogy of the binder, 3) understand and predict anion and cation leaching behavior of contaminants of concern, and 4) predict performance of the waste forms for which phase solubility and thermodynamic data are available. Characterization of the mineralogy is also important for understanding the buffering effects that the waste form has on infiltrating water / leachates. In summary, mixtures of Type II portland cement, Grade 100 ground granulated blast furnace slag (GGBFS) and carbon burn-out (CBO) Class F Fly ash which were hydrated with water contained hydrated phase assemblages typical of those reported in the literature. The calcium silicate hydrate phase assemblage in samples hydrated with the alkaline 4.4 M sodium salt simulated waste solution was found to be a function of the (CaO + MgO) / (SiO{sub 2} + Al{sub 2}O{sub 3}) ratio of the samples characterized. No significant differences were detected in samples cured 2 months and 14 months in sealed containers at ambient indoor temperatures. Slag and a blend of slag and cement hydrated with caustic 4.4 M Na salt solution resulted in the most crystalline matrix. In addition to poorly ordered C-S-H, these samples contained fairly well ordered C-S-H I (a precursor of 14A tobermorite) and 11 A Al-substituted tobermorite. These crystalline C-S-H phases did not form or were present in only trace amounts in slag blends containing about 45 to 62 mass percent fly ash. These slag-Class F fly ash blends had a higher silica plus alumina content relative to lime and magnesia than the blends that produced C-S-H I and Al-substituted tobermorite. The calcium silicate binder in the 10:45:45 mixture of cement: slag: fly ash was made up of poorly ordered C-S-H. The sample cured for 14 months may contain a small amount of the more crystalline calcium silicate hydrate phases. Layered double hydroxides in the hydrotalcite (magnesium-aluminum carbonate hydroxide) and hydrocalumite / AFm phases (calcium aluminum hydroxide) were present in mixtures containing slag. The specific phase(s) were not identified because these phases form solid solutions and have a considerable amount of overlap in their x-ray patterns. Sodium nitrate was the only sodium salt phase identified in x-ray diffraction patterns of the samples hydrated with salt solution. Drying during x-ray diffraction sample preparation may have resulted in precipitation of the sodium nitrate or it may have been present in the samples prior to x-ray sample preparation. Sodium sulfate, aluminate, and carbonate may have been incorporated in the structures of the layered double hydroxide (AFm) type phases. These mixed metal layered double hydroxides make up an important fraction of the matrix in the slag containing blends hydrated with caustic salt solution. They are among the few oxide-based phases that exhibit substantial, permanent anion exchange capacity [Kirkpatrick, et al. 1999, Plamer, et al., 2009, and Zhang and Reardon, 2003]. They also contribute to the structural properties of cementitious matrices [Taylor, 1997]. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2019

The Belle II Physics Book

The Belle II-Theory interface Platform (B2TiP) was created as a physics prospects working group of the Belle II collaboration in June 2014. It offered a platform where theorists and experimentalists work together to elucidate the potential impacts of the Belle II program, which includes a wide scope of physics topics: B physics, charm, τ, quarkonium physics, electroweak precision measurements and dark sector searches. It is composed of nine working groups (WGs), which are coordinated by teams of theory and experiment conveners: WG1) Semileptonic and leptonic B decays, WG2) Radiative and Electroweak penguins, WG3) φ1 and φ2 (time-dependent CP violation) measurements, WG4) φ3 measurement, WG5) Charmless hadronic B decay, WG6) Charm, WG7) Quarkonium(like), WG8) τ and lowmultiplicity processes, WG9) New Physics. We organised workshops twice a year from 2014 until 2016, which moved from KEK in Japan to Europe and the Americas, gathering experts in the respective fields to discuss with Belle II members. One of the goals for B2TiP was to propose so-called “golden- and silver-channels”: we asked each working group to choose among numerous possible measurements, those that would have the highest potential impact and to focus on them for the writeup. Theorists scrutinised the role of those measurements in terms of understanding the theory behind them, and estimated the theoretical uncertainties, now achievable as well as prospects for the future. For flavour physics, having tight control of hadronic uncertainties is one of the most crucial aspects in the field, and this is considered as an important criteria to determine the golden or silver-channels. Experimentalists, on the other hand, investigated the expected improvements with data from Belle II. For the channels where the errors are dominated by statistical uncertainties, or where systematic errors are reducible, the errors can decrease rapidly as more data becomes available. The impact of the upgraded performance from Belle II is a crucial element for reducing the uncertainties: we therefore include the latest available studies of the detector efficiency using Monte Carlo simulated events. We list the golden(silver)-channel table in this first chapter, as a guide for the chapters that follow. The book is not a collection of reports based on talks given at the workshops. The working group conveners endeavoured to construct a coherent document that can be used by Belle II collaborators, and others in the field of flavour physics, as a reference. There were two books of a similar type written in the past, “The BaBar book” [1] and “The Physics of the B factories” [2]. In order to avoid too much repetition with respect to those references, we refer to them as possible for introductory material. We would like to thank the section editors and contributing authors for the many stimulating discussions and their tremendous effort to bring the book together.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2018

Skluma: An extensible metadata extraction pipeline for disorganized data

To mitigate the effects of high-velocity data expansion and to automate the organization of filesystems and data repositories, we have developed Skluma-a system that automatically processes a target filesystem or repository, extracts content-and context-based metadata, and organizes extracted metadata for subsequent use. Skluma is able to extract diverse metadata, including aggregate values derived from embedded structured data; named entities and latent topics buried within free-text documents; and content encoded in images. Skluma implements an overarching probabilistic pipeline to extract increasingly specific metadata from files. It applies machine learning methods to determine file types, dynamically prioritizes and then executes a suite of metadata extractors, and explores contextual metadata based on relationships among files. The derived metadata, represented in JSON, describes probabilistic knowledge of each file that may be subsequently used for discovery or organization. Skluma's architecture enables it to be deployed both locally and used as an on-demand, cloud-hosted service to create and execute dynamic extraction workflows on massive numbers of files. It is modular and extensible-allowing users to contribute their own specialized metadata extractors. Thus far we have tested Skluma on local filesystems, remote FTP-accessible servers, and publicly-accessible Globus endpoints. We have demonstrated its efficacy by applying it to a scientific environmental data repository of more than 500,000 files. We show that we can extract metadata from those files with modest cloud costs in a few hours.

data swamp↗
DOE OSTI2025

Unlocking Scholarly Insights: Leveraging Machine Learning Approaches for Citation Analysis and Intent Classification

Publicly funded organizations, notably institutions like the Los Alamos National Laboratory (LANL), are deeply vested in acquiring robust productivity metrics to gauge the entirety of their research output. Motivated by the imperative to enhance institutional productivity assessment, this study investigates the utilization of Large Language Models (LLM) such as BERT-based models, as well as local LLaMa-30b-instruct and Mixtral-8x7b-instruct architectures for classifying type of URL referenced resources in academic papers such as software, dataset, as well as authorship intent. Challenges in discerning resource types from context are highlighted, along with the potential of BERT and LLMs to address these challenges. Through comprehensive analysis, this research unveils a notable surge in documents featuring URL citations, indicative of the escalating importance of digital resources in scholarly publications. Moreover, citations to datasets and software demonstrate consistent growth over time, underscoring their increasing significance. Our findings also reveal that LANL authors contribute substantially to accessible science, comprising about 10% of dataset and software mentions in LANL

Large Language Models, BERT, citation classificati↗
DOE OSTI2014

Review of Graph Databases for Big Data Dynamic Entity Scoring

Modeling data as a graph enables users to quickly analyze networked phenomenon, such as social network-based marketing data (e.g., linking entities in social media based on their friends and their "likes", their friend-of-a-friend's "likes", etc.) and scientific data, such as in biology to assess a gene's proximity in a graph to particular disease phenotype. Numerous purpose-built graph databases (DBs) called “NoSQL” or “Not Only SQL” DBs are emerging to support this type of graph analysis. These DBs differ from traditional relational DBs in that they are optimized to improve storage and query performance across large, complex graphs. This document reviews the state of the art in graph DBs and identifies potential DBs that show promise for dynamic entity-scoring algorithms. Dynamic entity scoring is a new area of research that allows analysis of data within graphs using undirected methods to weigh the edges of the graph based on the proximity or ambient influence of near-by nodes. The EntityScore (eScore) methodology developed at Lawrence Livermore National Laboratory (LLNL) is one application of these emerging graph-analysis algorithms to help analysts identify and prioritize entities, based on complex, analyst-defined weighting criteria. Our review examines a wide range of different, well-known graph DBs in use since at least 2010 and identifies unique advantages and disadvantages that may impact eScore-specific requirements. Specifically, we review data structures employed, query features employed, load times, query calculation times, memory usage and several other important attributes reported in the literature. We limited our considerations for eScore to Blueprints-compliant graph DBs (https://github.com/tinkerpop/blueprints/) because they provide a standard, java application programming interface (API) based on the property graph model.

42 ENGINEERING↗
DOE OSTI2017

Contaminant Attenuation and Transport Characterization of 200-UP-1 Operable Unit Sediment Samples

Contaminants disposed of at the land surface migrate through the vadose zone, forming plumes in groundwater. Processes that occur in the groundwater can attenuate contaminant concentrations during transport through the aquifer. For this reason, quantifying contaminant attenuation and contaminant transport processes in the aquifer, in support of the conceptual site model (CSM) and fate and transport modeling, are important for assessing the need for, and type of, remediation in the groundwater, including monitored natural attenuation (MNA). The framework to characterize attenuation and transport processes provided in U.S. Environmental Protection Agency (EPA) guidance documents was used to guide the laboratory effort reported herein.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2018

Absorber Cooling Circuits Dynamic Pressure Study

The flow rates through the flange/stick absorber cooling circuit and the crotch absorber cooling circuit should not exceed 2 GPM. The purpose of this document is to define the scope and present the results of the NSLSII absorber circuit water cooling pressure test. This report also provides flow capacities for each type of absorber cooling circuit in accordance with the required header pressure differential and other cooling system design parameters.

43 PARTICLE ACCELERATORS↗