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2017 Guralp Affinity Digitizer Evaluation

Merchant, Bion J.

Sandia National Laboratories has tested and evaluated two Guralp Affinity digitizers. The Affinity digitizers are intended to record sensor output for seismic and infrasound monitoring applications. The purpose of this digitizer evaluation is to measure the performance characteristics in such areas as power consumption, input impedance, sensitivity, full scale, self- noise, dynamic range, system noise, response, passband, and timing. The Affinity digitizers are being evaluated for potential use in the International Monitoring System (IMS) of the Comprehensive Nuclear Test-Ban-Treaty Organization (CTBTO).

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TYPE SAND Report YEAR 2018
DOIDOIOSTIOSTI

The Rocket Test Case Study

Heimer, Brandon W.; Reinhardt, Jason C.; Burks, Lynne S.

Suppose Tom is working to develop a rocket. Susan is very interested in knowing what Tom is doing but cannot directly observe his testing of the rocket propulsion system. Specifically, she would like to know if Tom has the ability to launch a heavy rocket or a light rocket. She thinks she can learn about Tom’s capability by learning about what type of rocket engine Tom is using, and the number of rockets in the design. She is considering buying a special sensor that can observe flashes from the rocket firing up during the tests and indicate if the rockets fire in a sufficiently narrow window of time such that they would successfully lift a heavy rocket.

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TYPE Other Report YEAR 2018
DOIDOIOSTIOSTI

Socio-behavioral considerations in the role of militant extremism

Bernard, Michael L.; Backus, George A.; Beyeler, Walter E.

This paper discusses relevant findings and theories regarding the role of ideology, culture, and context in shaping the behaviors of individuals within violent social movements. Accordingly, this focus concerns the comparative weight placed on ideology and culture (expressed principles and motives) versus external factors as chief influencers for the propensity of individuals to act outside of the norms of society and politics by resorting to violent behaviors. In doing so, we have drawn upon theory from anthropology, behavioral economics, political science, psychology, and sociology to better understand how these variables give birth to and nurture militant social movements. F u r t h e r d i s s e m i n a t i o n o n l y a s a u t h o r i z e d t o U . S . G o v e r n m e n t a g e n c i e s a n d t h e i r c o n t r a c t o r s ; o t h e r r e q u e s t s s h a l l b e a p p r o v e d b y t h e o r i g i n a t i n g f a c i l i t y o r h i g h e r D O E p r o g r a m m a t i c a u t h o r i t y .

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TYPE SAND Report YEAR 2018
DOIDOIOSTIOSTI

DOE Big Idea Summit III: Solving the Information Technology Challenge Beyond Moore's Law: A New Path to Scaling

McCormick, Frederick B.; Shalf, John; Mitchell, Alan M.; Lentine, Anthony L.; Marinella, Matthew J.

This report captures the initial conclusions of the DOE seven National Lab team collaborating on the “Solving the Information Technology Energy Challenge Beyond Moore’s Law” initiative from the DOE Big Idea Summit III held in April of 2016. The seven Labs held a workshop in Albuquerque, NM in late July 2016 and gathered 40 researchers into 5 working groups: 4 groups spanning the levels of the co-design framework shown below, and a 5th working group focused on extending and advancing manufacturing approaches and coupling their constraints to all of the framework levels. These working groups have identified unique capabilities within the Labs to support the key challenges of this Beyond Moore’s Law Computing (BMC) vision, as well as example first steps and potential roadmaps for technology development.

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TYPE Other Report YEAR 2018
DOIDOIOSTIOSTI

Rotary Vapor Compression Cycle Final Report

Kariya, Harumichi A.; Koplow, Jeffrey P.; Staats, Wayne L.

While there are several heat pump technologies such thermoelectric, adsorption and magnetocaloric cycles, the oldest and most widely used is the vapor compression cycle (VCC). Currently, thermoelectric cycles have not yet achieved efficiencies nor cooling capacities comparable to VCCs. Adsorption cycles offer the benefit of using low-quality heat as the energy input, but are significantly more complex and expensive and are therefore limited to certain niche applications. Magnetocaloric cycles are still in the research phase. Consequently, improvements made for VCCs will likely have the most immediate and encompassing impact. The objective of this work is to develop an alternative VCC topology to reduce the above inefficiencies.

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TYPE Other Report YEAR 2018
DOIOSTIDOIOSTI

Sierra/SolidMechanics 4.48 Verification Tests Manual

Plews, Julia A.; Crane, Nathan K.; de Frias, Gabriel J.; Le, San L.; Littlewood, David J.; Merewether, Mark T.; Mosby, Matthew D.; Pierson, Kendall H.; Porter, V.L.; Shelton, Timothy S.; Thomas, Jesse D.; Tupek, Michael R.; Veilleux, Michael V.; Xavier, Patrick G.

Presented in this document is a small portion of the tests that exist in the Sierra / SolidMechanics (Sierra / SM) verification test suite. Most of these tests are run nightly with the Sierra / SM code suite, and the results of the test are checked versus the correct analytical result. For each of the tests presented in this document, the test setup, a description of the analytic solution, and comparison of the Sierra / SM code results to the analytic solution is provided. Mesh convergence is also checked on a nightly basis for several of these tests. This document can be used to confirm that a given code capability is verified or referenced as a compilation of example problems. Additional example problems are provided in the Sierra / SM Example Problems Manual. Note, many other verification tests exist in the Sierra / SM test suite, but have not yet been included in this manual.

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TYPE SAND Report YEAR 2018
DOIOSTIDOIOSTI

Directional Unfolded Source Term (DUST) for Compton Cameras

Mitchell, Dean J.; Horne, Steven M.; O'Brien, Sean O.; Thoreson, Gregory G.

A Directional Unfolded Source Term (DUST) algorithm was developed to enable improved spectral analysis capabilities using data collected by Compton cameras. Achieving this objective required modification of the detector response function in the Gamma Detector Response and Analysis Software (GADRAS). Experimental data that were collected in support of this work include measurements of calibration sources at a range of separation distances and cylindrical depleted uranium castings.

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TYPE SAND Report YEAR 2018
DOIOSTI

PFLOTRAN-RepoTREND Source Term Comparison Summary

Frederick, Jennifer M.

Code inter-comparison studies are useful exercises to verify and benchmark independently developed software to ensure proper function, especially when the software is used to model high-consequence systems which cannot be physically tested in a fully representative environment. This summary describes the results of the first portion of the code inter-comparison between PFLOTRAN and RepoTREND, which compares the radionuclide source term used in a typical performance assessment.

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TYPE SAND Report YEAR 2018
DOIOSTI

Flexible Foam Model

Neilsen, Michael K.; Lu, Wei-Yang L.; Werner, Brian T.; Scherzinger, William M.; Lo, Chi S.

Experiments were performed to characterize the mechanical response of a 15 pcf flexible polyurethane foam to large deformation at different strain rates and temperatures. Results from these experiments indicated that at room temperature, flexible polyurethane foams exhibit significant nonlinear elastic deformation and nearly return to their original undeformed shape when unloaded. However, when these foams are cooled to temperatures below their glass transition temperature of approximately -35 o C, they behave like rigid polyurethane foams and exhibit significant permanent deformation when compressed. Thus, a new model which captures this dramatic change in behavior with temperature was developed and implemented into SIERRA with the name Flex_Foam to describe the mechanical response of both flexible and rigid foams to large deformation at a variety of temperatures and strain rates. This report includes a description of recent experiments. Next, development of the Flex Foam model for flexible polyurethane and other flexible foams is described. Selection of material parameters are discussed and finite element simulations with the new Flex Foam model are compared with experimental results to show behavior that can be captured with this new model.

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TYPE SAND Report YEAR 2018
DOIOSTI

Mo99 Draft Report

Seestrom, Susan J.

The Nuclear Science Advisory Committee (NSAC) 99Molybdenum (99Mo) Subcommittee met December 14-15, 2017 to address the charge to NSAC requesting that a fourth annual review of the National Nuclear Security Administration (NNSA) 99Mo program be performed. The Subcommittee found that the NNSA has continued to make progress over the course of the year based on the specific American Medical Isotopes Production Act of 2012 (AMIPA) requirements.

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TYPE Other Report YEAR 2018
DOIOSTI

Infrasound Predictions Using the Weather Research and Forecasting Model: Atmospheric Green's Functions for the Source Physics Experiments 1-6

Poppeliers, Christian P.; Aur, Katherine A.; Preston, Leiph A.

This report shows the results of constructing predictive atmospheric models for the Source Physics Experiments 1-6. Historic atmospheric data are combined with topography to construct an atmo- spheric model that corresponds to the predicted (or actual) time of a given SPE event. The models are ultimately used to construct atmospheric Green's functions to be used for subsequent analysis. We present three atmospheric models for each SPE event: an average model based on ten one- hour snap shots of the atmosphere and two extrema models corresponding to the warmest, coolest, windiest, etc. atmospheric snap shots. The atmospheric snap shots consist of wind, temperature, and pressure profiles of the atmosphere for a one-hour time window centered at the time of the predicted SPE event, as well as nine additional snap shots for each of the nine preceding years, centered at the time and day of the SPE event.

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TYPE SAND Report YEAR 2018
DOIDOIOSTIOSTI

SunShot Innovator in Residence Final Report

Koplow, Jeffrey P.

This report describes the development of Radical-Ion Flow Battery (RIFB) technology for electrochemical grid storage, and solar thermochemical cycles for conversion of concentrated solar energy to stored chemical energy. The Radical-Ion Flow Battery stores energy via electrolysis of a molten salt electrolyte such as NaNO2 into an alkali metal and nitrogen dioxide, both of which can be stored as liquids in non-pressurized tanks. The use of extremely facile ion-radical single electron transfer reactions at both electrodes that entail no breaking of covalent bonds is directed towards minimizing thermodynamic irreversibility in the charge/discharge cycle, and eliminating the need for catalytically active electrode materials. Both kinetics and mass transport are also facilitated by the absence of diluent species; the battery electrolyte and active chemical ingredient are one and the same. Our underlying strategy for low-cost scalability is the use of only earth abundant starting materials (NaCl, N2, O2, and steel). The underlying strategy for avoiding the problem of capacity fade over 10,000 charge/discharge cycles is the use of extremely simple chemistry. It is argued that operation at elevated temperature is highly advantageous for very large-scale batteries from the standpoint of battery heat-sinking, access to ultrahigh conductivity electrolytes, and increased electrochemical kinetic rate constants. Numerous practical considerations, such as seals, insulators, and electrical feedthroughs are examined in detail, as are questions related to low-cost mass production and battery techno-economic analysis.

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TYPE Other Report YEAR 2018
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Hybrid Integration of III-V Solar Microcells for High-Efficiency Concentrated Photovoltaic Modules

IEEE Journal of Selected Topics in Quantum Electronics

Tauke-Pedretti, Anna; Cederberg, Jeffrey G.; Cruz-Campa, Jose L.; Alford, Charles A.; Sanchez, Carlos A.; Sweatt, W.C.; Jared, Bradley H.; Keeler, Gordon A.; Paap, Scott M.; Okandan, Murat; Li, Lan; Li, Duanhui; Gu, Tian; Hu, Juejun; Nielson, Gregory N.

The design, fabrication, and performance of InGaAs and InGaP/GaAs microcells are presented. These cells are integrated with a Si wafer providing a path for insertion in hybrid concentrated photovoltaic modules. Comparisons are made between bonded cells and cells fabricated on their native wafer. The bonded cells showed no evidence of degradation in spite of the integration process that involved significant processing including the removal of the III-V substrate.

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TYPE Journal Article YEAR 2018
DOIOSTIScopusDOIOSTIScopus
Results 29201–29400 of 96,771
Results 29201–29400 of 96,771