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A Window-less Target for Magnetized Liner Inertial Fusion Characterized using High-Speed Solid-State Framing Cameras

Colombo, Anthony; Schwarz, Jens; Rambo, Patrick K.; Galloway, Benjamin R.; Kimmel, Mark; Slutz, Stephen A.; Weis, Matthew R.; Claus, Liam; England, Troy D.; Fang, Lu; Looker, Quinn M.; Mitchell, Brandon; Montoya, Andrew; Robertson, Gideon; Rochau, Gregory A.; Sanchez, Marcos O.; Stahoviak, John W.; Hund, Jared; Sin, Justin; Porter, John L.

Abstract not provided.

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TYPE Conference Poster YEAR 2018
OSTI

Next Generation Anodes for Lithium-ion Batteries: Thermodynamic Understanding and Abuse Performance

Fenton, Kyle R.; Allcorn, Eric; Nagasubramanian, Ganesan

As we develop new materials to increase performance of lithium ion batteries for electric vehicles, the impact of potential safety and reliability issues become increasingly important. In addition to electrochemical performance increases (capacity, energy, cycle life, etc.), there are a variety of materials advancements that can be made to improve lithium-ion battery safety. Issues including energetic thermal runaway, electrolyte decomposition and flammability, anode SEI stability, and cell-level abuse tolerance behavior. Introduction of a next generation materials, such as silicon based anode, requires a full understanding of the abuse response and degradation mechanisms for these anodes. This work aims to understand the breakdown of these materials during abuse conditions in order to develop an inherently safe power source for our next generation electric vehicles.

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TYPE Other Report YEAR 2018
DOIOSTI

Discharge Permit-1845 Quarterly Status Report April 2018

Li, Jun

Discharge Permit (DP)-1845 was issued by the New Mexico Environment (NMED) Ground Water Quality Bureau (GWQB) for discharges via up to three injection wells in a phased Treatability Study of in-situ bioremediation of groundwater at Sandia National Laboratories, New Mexico, Technical Area-V Groundwater Area of Concern. This report fulfills the quarterly reporting requirements set forth in DP-1845, Section IV.B, Monitoring and Reporting. This reporting period is October 1st through December 31st, 2017. The report is due to NMED GWQB by May 1st, 2018.

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TYPE Other Report YEAR 2018
DOIOSTI

Compressed sensing with sparse corruptions: Fault-tolerant sparse collocation approximations

Adcock, Ben; Bao, Anyi; Jakeman, John D.; Naryan, Akil

The recovery of approximately sparse or compressible coefficients in a polynomial chaos expansion is a common goal in many modern parametric uncertainty quantification (UQ) problems. However, relatively little effort in UQ has been directed toward theoretical and computational strategies for addressing the sparse corruptions problem, where a small number of measurements are highly corrupted. Such a situation has become pertinent today since modern computational frameworks are sufficiently complex with many interdependent components that may introduce hardware and software failures, some of which can be difficult to detect and result in a highly polluted simulation result. In this paper we present a novel compressive sampling-based theoretical analysis for a regularized t1 minimization algorithm that aims to recover sparse expansion coefficients in the presence of measurement corruptions. Our recovery results are uniform (the theoretical guarantees hold for all compressible signals and compressible corruptions vectors), and prescribe algorithmic regularization parameters in terms of a user-defined a priori estimate on the ratio of measurements that are believed to be corrupted. We also propose an iteratively reweighted optimization algorithm that automatically refines the value of the regularization parameter, and empirically produces superior results. Our numerical results test our framework on several medium-to-high dimensional examples of solutions to parameterized differential equations, and demonstrate the effectiveness of our approach.

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TYPE Other Report YEAR 2018
DOIOSTI

ECP ST Capability Assesment Report VTK-m

Moreland, Kenneth D.

The ECP/VTK-m project is providing the core capabilities to perform scientific visualization on exascale architectures. The ECP/VTK-m project fills the critical feature gap of performing visualization and analysis on processors like graphics-based processors and many integrated core. The results of this project will be delivered in tools like Para View, Vislt, and Ascent as well as in stand-alone form. Moreover, these projects are depending on this ECP effort to be able to make effective use of ECP architectures.

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TYPE Other Report YEAR 2018
DOIOSTI

Cray System Monitoring: Successes Requirements and Priorities

Ahlgren, Ville; Andersson, Stefan; Brandt, James M.; Cardo, Nicholas; Chunduri, Sudheer; Enos, Jeremy; Fields, Parks; Gentile, Ann C.; Gerber, Richard; Greenseid, Joe; Greiner, Annette; Hadri, Bilel; He, Yun; Hoppe, Dennis; Kaila, Urpo; Kelly, Kaki; Klein, Mark; Kristiansen, Alex; Leak, Steve; Mason, Mike; Pedretti, Kevin; Piccinali, Jean-Guillaume; Repik, Jason J.; Rogers, Jim; Salminen, Susanna; Showerman, Mike; Whitney, Cary; Williams, Jim

Abstract not provided.

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TYPE Conference Poster YEAR 2018
OSTI

Recent research on stishovite: Hugoniot and partial release Z experiments and DFT EOS calculations

Furnish, Michael D.; Shulenburger, Luke; Desjarlais, Michael; Fei, Yingwei

We have conducted a series of ride-along experiments on the Z facility to ascertain the Hugoniot of silica centered in the stishovite phase over a range 0.4 - 1.0 TPa, together with partial release states produced at the interface between the sample and a fused silica window. The stishovite samples were synthesized in a large-volume multi-anvil press at 15 GPa and 1773 K, with an initial density of 4.29 gm/cc. The new Z experiments on stishovite fill in a gap between gas gun experiments and NIF experiments. The states are compared with the Hugoniots of quartz and fused silica for inferences as to EOS. They are generally consistent with Sesame 7360 predictions. Sound speed constraints from these data are discussed. The new Hugoniot data cross over the melting curve of stishovite; together with the partial-release data and predictions from density-functional theory modeling, they provide insights into the properties of solid and liquid under extreme conditions. These data are fundamentally important for understanding the interior of silicate-based super-Earths.

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TYPE SAND Report YEAR 2018
DOIOSTI

A Minimum Variance Algorithm for Overdetermined TOA Equations with an Altitude Constraint

Romero, Louis A.; Mason, John J.

We present a direct (non-iterative) method for solving for the location of a radio frequency (RF) emitter, or an RF navigation receiver, using four or more time of arrival (TOA) measurements and an assumed altitude above an ellipsoidal earth. Both the emitter tracking problem and the navigation application are governed by the same equations, but with slightly different interpreta- tions of several variables. We treat the assumed altitude as a soft constraint, with a specified noise level, just as the TOA measurements are handled, with their respective noise levels. With 4 or more TOA measurements and the assumed altitude, the problem is overdetermined and is solved in the weighted least squares sense for the 4 unknowns, the 3-dimensional position and time. We call the new technique the TAQMV (TOA Altitude Quartic Minimum Variance) algorithm, and it achieves the minimum possible error variance for given levels of TOA and altitude estimate noise. The method algebraically produces four solutions, the least-squares solution, and potentially three other low residual solutions, if they exist. In the lightly overdermined cases where multiple local minima in the residual error surface are more likely to occur, this algebraic approach can produce all of the minima even when an iterative approach fails to converge. Algorithm performance in terms of solution error variance and divergence rate for bas eline (iterative) and proposed approach are given in tables.

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TYPE SAND Report YEAR 2018
DOIOSTI

SecPop Version 4: Sector Population Land Fraction and Economic Estimation Program: Users? Guide Model Manual and Verification Report

Weber, Scott; Bixler, Nathan E.; Mcfadden, Katherine

In 1973 the U.S. Environmental Protection Agency (EPA) developed SecPop to calculate population estimates to support a study on air quality. The Nuclear Regulatory Commission (NRC) adopted this program to support siting reviews for nuclear power plant construction and license applications. Currently SecPop is used to prepare site data input files for offsite consequence calculations with the MELCOR Accident Consequence Code System (MACCS). SecPop enables the use of site-specific population, land use, and economic data for a polar grid defined by the user. Updated versions of SecPop have been released to use U.S. decennial census population data. SECPOP90 was released in 1997 to use 1990 population and economic data. SECPOP2000 was released in 2003 to use 2000 population data and 1997 economic data. This report describes the current code version, SecPop version 4.3, which uses 2010 population data and both 2007 and 2012 economic data. It is also compatible with 2000 census and 2002 economic data. At the time of this writing, the current version of SecPop is 4.3.0, and that version is described herein. This report contains guidance for the installation and use of the code as well as a description of the theory, models, and algorithms involved. This report contains appendices which describe the development of the 2010 census file, 2007 county file, and 2012 county file. Finally, an appendix is included that describes the validation assessments performed.

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TYPE Other Report YEAR 2018
DOIOSTI

Exploiting Geometric Partitioning in Task Mapping for Parallel Computes

Deveci, Mehmet; Devine, Karen; Bays, Nathan R.; Taylor, Mark A.; Rajamanickam, Sivasankaran; Catalyurek, Umit V.

We present a new method for mapping applications' MPI tasks to cores of a parallel computer such that applications' communication time is reduced. We address the case of sparse node allocation, where the nodes assigned to a job are not necessarily located in a contiguous block nor within close proximity to each other in the network, although our methods generalize to contiguous allocations as well. The goal is to assign tasks to cores so that interdependent tasks are performed by "nearby' cores, thus lowering the distance messages must travel, the amount of congestion in the network, and the overall cost of communication. Our new method applies a geometric partitioning algorithm to both the tasks and the processors, and assigns task parts to the corresponding processor parts. We also present a number of algorithmic optimizations that exploit specific features of the network or application. We show that, for the structured finite difference mini-application MiniGhost, our mapping methods reduced communication time up to 75% relative to MiniGhost's default mapping on 128K cores of a Cray XK7 with sparse allocation. For the atmospheric modeling code E3SM/HOMME, our methods reduced communication time up to 31% on 32K cores of an IBM BlueGene/Q with contiguous allocation.

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TYPE Other Report YEAR 2018
DOIOSTI

Terry Turbopump Analytical Modeling Efforts in Fiscal Year 2016 - Progress Report

Osborn, Douglas M.; Ross, Kyle; Cardoni, Jeffrey

This document details the Fiscal Year 2016 modeling efforts to define the true operating limitations (margins) of the Terry turbopump systems used in the nuclear industry for Milestone 3 (full-scale component experiments) and Milestone 4 (Terry turbopump basic science experiments) experiments. The overall multinational-sponsored program creates the technical basis to: (1) reduce and defer additional utility costs, (2) simplify plant operations, and (3) provide a better understanding of the true margin which could reduce overall risk of operations.

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TYPE SAND Report YEAR 2018
DOIOSTI

Grain Boundary Diffusion Characterized by KPFM

Baca, Ana B.; Brumbach, Michael T.; Vianco, Paul T.; Patterson, Burton; Scrymgeour, David A.

Materials aging is a high-consequence failure mode in electronic systems. Such mechanisms can degrade the electrical properties of connectors, relays, wire bonds, and other interconnections. Lost performance will impact, not only that of the device, but also the function and reliability of next-level assemblies and the weapons system as a whole. The detections of changes to materials surfaces at the nanometer-scale resolution, provides a means to identify aging processes at their early stages before they manifest into latent failures that affect system-level performance and reliability. Diffusion will be studied on thin films that undergo accelerated aging using the nanometer scale characterization technique of Frequency Modulated Kelvin Probe Force Microscopy (FM-KPFM). The KPFM provides a relatively easy, non-destructive methodology that does not require high-vacuum facilities to obtain nanometer spatial resolution of surface chemistry changes. The KPFM method can provide the means to measure surface, and near-surface, elemental concentrations that allow the determination of diffusion rate kinetics. These attributes will be illustrated by assessing diffusion in a thin film couple. Validation data will obtained from traditional techniques: (a) Auger electron spectroscopy (AES), x-ray fluorescence (XRF), and xray photoelectron spectroscopy (XPS).

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TYPE Other Report YEAR 2018
DOIOSTI

DOE OE Energy Storage Systems Safety Roadmap Focus on Proposed Changes to the ICC International Codes Special Briefing Paper — Unofficial Hearing Results April 2018

Conover, David

The goal of the DOE OE ESS Safety Roadmap1 is to foster confidence in the safety and reliability of energy storage systems (ESSs). Three interrelated objectives support the realization of that goal: research, codes and standards, and communication/coordination. The objective focused on codes and standards is - To apply research and development (R&D) to support efforts that are focused on ensuring that codes and standards are available to enable the safe implementation of ESSs in a comprehensive, non-discriminatory and science-based manner. The purpose of this special briefing paper is to support the above objective by providing information about current and upcoming efforts being conducted by U.S. standards developing organizations, specifically code changes associated with the 2018 Group A International Codes (I-Codes) of the International Code Council (ICC) that are relevant to ESSs.

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TYPE Other Report YEAR 2018
DOIOSTI

MagLIFEP and MagLIFSNL

Harvey-Thompson, Adam J.; Wei, Mingsheng; Glinsky, Michael E.; Weis, Matthew R.; Nagayama, Taisuke; Peterson, K.J.; Fooks, J.; Giraldez, E.; Krauland, C.; Campbell, M.; Davies, J.; Peebles, J.; Bahr, R.; Edgell, D.; Stoeckl, C.; Turnbull, D.; Glebov, V.; Emig, J.; Heeter, R.; Strozzi, D.

The MagLIF campaign operated by Sandia conducted a total of four shot days in FY17 (one on OMEGA and three on OMEGA-EP) aimed at characterizing the laser heating of underdense plasmas (D2, Ar) at parameters that are relevant to the Magnetized Liner Inertial Fusion (MagLIF) ICF scheme being pursued at Sandia National Laboratories [1] [2]. MagLIF combines fuel preheat, magnetization and pulsed power implosion to significantly relax the implosion velocity and pR required for self-heating. Effective fuel preheat requires coupling several kJ of laser energy into the 10 mm long, underdense (typically ne/nc<0.1) fusion fuel without introducing significant mix. Barriers to achieving this include the presence laser plasma instabilities (LPI) as laser energy is coupled to the initially cold fuel, and the presence of a thin, polyimide laser entrance hole (LEH) foil that the laser must pass through and that can be a significant perturbation.

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TYPE Other Report YEAR 2018
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Material Failure Model and Properties for Puncture Simulations

Hubbard, Neal B.

Sharp tools in a production environment can puncture fragile components. This project analyzes a slender probe as it penetrates a ductile material. Finite element models of probe penetration problems need material models that are accurate through the full range of strain. Elastic properties are frequently derived and are available for most metals with a strong statistical basis. Stress-strain curves including the plastic range are limited and usually stop at the ultimate strength, where void nucleation occurs. Criteria for damage accumulation and rupture are difficult to obtain for many materials. Tests have been performed on coupons of 7075-T651 plate with three probes. The geometry of the coupon and probes are provided, as well as appropriate initial and boundary conditions. The mean energy required for each of the probes to penetrate the coupon is also provided. The objective of this project is to demonstrate three advanced material models for 7075-T651 plate with failure criteria and derive the requisite parameters for each model.

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TYPE Other Report YEAR 2018
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Beyond the Fluid Approximation: Improved Modeling of the Intracluster Plasma

O'Shea, Brian W.; Christlieb, Andrew; Beckwith, Kristian

This is the progress report for the grant "Beyond the Fluid Approximation: Improved Modeling of the Intracluster Plasma." We have made progress along several fronts, including code development and science. One paper has been published, and a second has been submitted and is about to be accepted. These are described below.

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TYPE Other Report YEAR 2018
DOIOSTI

Artificial Diversity and Defense Security (ADDSec) Final Report

Chavez, Adrian R.; Hamlet, Jason; Stout, William M.S.

Critical infrastructure systems continue to foster predictable communication patterns and static configurations over extended periods of time. The static nature of these systems eases the process of gathering reconnaissance information that can be used to design, develop, and launch attacks by adversaries. In this research effort, the early phases of an attack vector will be disrupted by randomizing application port numbers, IP addresses, and communication paths dynamically through the use of overlay networks within Industrial Control Systems (ICS). These protective measures convert static systems into "moving targets," adding an additional layer of defense. Additionally, we have developed a framework that automatically detects and defends against threats within these systems using an ensemble of machine learning algorithms that classify and categorize abnormal behavior. Our proof-of-concept has been demonstrated within a representative ICS environment. Performance metrics of our proof-of-concept have been captured with latency impacts of less than a millisecond, on average.

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TYPE SAND Report YEAR 2018
DOIOSTI

US Sections Prepared for Future NEA Crystalline Club (CRC) Report on Status of R&D in CRC Countries Investigating Deep Geologic Disposal in Crystalline Rock

Mariner, Paul E.; Stein, Emily; Kalinina, Elena A.; Hadgu, Teklu; Jove-Colon, Carlos; Basurto, Eduardo

U.S. knowledge in deep geologic disposal in crystalline rock is advanced and growing. U.S. status and recent advances related to crystalline rock are discussed throughout this report. Brief discussions of the history of U.S. disposal R&D and the accumulating U.S. waste inventory are presented in Sections 3.x.2 and 3.x.3. The U.S. repository concept for crystalline rock is presented in Section 3.x.4. In Chapters 4 and 5, relevant U.S. research related to site characterization and repository safety functions are discussed. U.S. capabilities for modelling fractured crystalline rock and performing probabilistic total system performance assessments are presented in Chapter 6.

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TYPE Other Report YEAR 2018
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Results 32201–32400 of 101,000
Results 32201–32400 of 101,000
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