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Terry Turbopump Expanded Operating Band Full-Scale Component and Basic Science Detailed Test Plan - Final

Osborn, Douglas; Solom, Matthew

This document details the milestone approach 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) efforts. 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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Test Plan for the Wake Steering Experiment at the Scaled Wind Farm Technology (SWiFT) Facility

Naughton, Brian

This document is a test plan describing the objectives, configuration, procedures, reporting, roles, and responsibilities for conducting the joint Sandia National Laboratories and National Renewable Energy Laboratory Wake Steering Experiment at the Sandia Scaled Wind Farm Technology (SWiFT) facility near Lubbock, Texas in 2016 and 2017 . The purpose of this document is to ensure the test objectives and procedures are sufficiently detailed such that al l involved personnel are able to contribute to the technical success of the test. This document is not intended to address safety explicitly which is addressed in a separate document listed in the references titled Sandia SWiFT Facility Site Operations Manual . Both documents should be reviewed by all test personnel.

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Recommended Research Directions for Improving the Validation of Complex Systems Models

Vugrin, Eric; Trucano, Timothy G.; Swiler, Laura P.; Finley, Patrick D.; Flanagan, Tatiana P.; Naugle, Asmeret B.; Tsao, Jeffrey Y.; Verzi, Stephen J.

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Properties of Syntactic Foam for Simulation of Mechanical Insults

Hubbard, Neal B.; Haulenbeek, Kimberly K.; Spletzer, Matthew; Ortiz, Lyndsy

Syntactic foam encapsulation protects sensitive components. The energy mitigated by the foam is calculated with numerical simulations. The properties of a syntactic foam consisting of a mixture of an epoxy-rubber adduct and glass microballoons are obtained from published literature and test results. The conditions and outcomes of the tests are discussed. The method for converting published properties and test results to input for finite element models is described. Simulations of the test conditions are performed to validate the inputs.

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Messier: A Detailed NVM-Based DIMM Model for the SST Simulation Framework

Awad, Amro; Voskuilen, Gwendolyn R.; Rodrigues, Arun; Hammond, Simon; Hoekstra, Robert J.; Hughes, Clayton

DRAM technology is the main building block of main memory, however, DRAM scaling is becoming very challenging. The main issues for DRAM scaling are the increasing error rates with each new generation, the geometric and physical constraints of scaling the capacitor part of the DRAM cells, and the high power consumption caused by the continuous need for refreshing cell values. At the same time, emerging Non- Volatile Memory (NVM) technologies, such as Phase-Change Memory (PCM), are emerging as promising replacements for DRAM. NVMs, when compared to current technologies e.g., NAND-based ash, have latencies comparable to DRAM. Additionally, NVMs are non-volatile, which eliminates the need for refresh power and enables persistent memory applications. Finally, NVMs have promising densities and the potential for multi-level cell (MLC) storage.

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TCIA Secure Cyber Critical Infrastructure Modernization

Keliiaa, Curtis M.

The Sandia National Laboratories (Sandia Labs) tribal cyber infrastructure assurance initiative was developed in response to growing national cybersecurity concerns in the the sixteen Department of Homeland Security (DHS) defined critical infrastructure sectors1. Technical assistance is provided for the secure modernization of critical infrastructure and key resources from a cyber-ecosystem perspective with an emphasis on enhanced security, resilience, and protection. Our purpose is to address national critical infrastructure challenges as a shared responsibility.

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Visualization of Radioisotope Detectability Over Time

Huynh, Brady

A radioactive isotope is an atom that has an unstable nucleus. The isotope can undergo radioactive decay, the process in which excessive nuclear energy is emitted from the nucleus in many different forms, such as gamma radiation, alpha particles, or beta particles. The important thing to note is that these emissions act as a signature for the isotope. Each radioisotope has a particular emission spectrum, emitting radiation at different energies and at different rates.

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Solid Waste Management Units And Areas Of Concern Annual Long-Term Monitoring & Maintenance Report For Calendar Year 2016

Dotson, Patrick W.; Little, Bonnie C.

Long-term controls were maintained at 21 Solid Waste Management Units (SWMUs) and Areas of Concern (AOCs) in accordance with the requirements of the “Long-Term Monitoring and Maintenance Plan for SWMUs and AOCs Granted Corrective Action Complete with Controls” in Attachment M of the Resource Conservation and Recovery Act Facility Operating Permit, which took effect February 26, 2015. Maintenance and controls at these SWMUs and AOCs are described and documented in this report. Conditions requiring maintenance or repair activities were not identified for any of the inspected SWMUs or AOCs. Based upon the inspections performed and site conditions observed, the administrative and physical institutional controls in place at the SWMUs and AOCs are effectively providing continued protection of human health and the environment. This report does not present monitoring and maintenance activities for SWMU 76, the Mixed Waste Landfill; those activities adhere to the approved MWL LTMM Plan, Section 4.8.1 requiring a separate annual report which will be submitted to the NMED by June 30, 2017.

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Statistical Framework for Planning a Component Shelf Life Program

Crowder, Stephen V.

This document outlines a statistical framework for establishing a shelf-life program for components whose performance is measured by the value of a continuous variable such as voltage or function time. The approach applies to both single measurement devices and repeated measurement devices, although additional process control charts may be useful in the case of repeated measurements. The approach is to choose a sample size that protects the margin associated with a particular variable over the life of the component. Deviations from expected performance of the measured variable are detected prior to the complete loss of margin. This ensures the reliability of the component over its lifetime.

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Footprint of Sandia's August 15 2016 Informal Idea Exploration Session on "Towards an Engineering and Applied Science of Research"

Tsao, Jeffrey Y.; Fleming, Elizabeth S.; Heffelfinger, Grant S.; Narayanamurti, Venkatesh; Schneider, Rick; Starkweather, Lynne M.; Ting, Christina; Yajima, Rieko; Bauer, Travis L.; Coltrin, Michael E.; Guy, Donald; Jones, Wendell; Mareda, John F.; Nenoff, Tina M.; Turnley, Jessica G.

On August 15, 2016, Sandia hosted a visit by Professor Venkatesh Narayanamurti. Prof Narayanamurti (Benjamin Peirce Research Professor of Technology and Public Policy at Harvard, Board Member of the Belfer Center for Science and International Affairs, former Dean of the School of Engineering and Applied Science at Harvard, former Dean of Engineering at UC Santa Barbara, and former Vice President of Division 1000 at Sandia). During the visit, a small, informal, all-day idea exploration session on "Towards an Engineering and Applied Science of Research" was conducted. This document is a brief synopsis or "footprint" of the presentations and discussions at this Idea Exploration Session. The intent of this document is to stimulate further discussion about pathways Sandia can take to improve its Research practices.

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Deployment Efficiency and Barrier Effectiveness Testing of a Temporary Anti-Personnel (TAP) Barrier System

Allen, David; Hedrick, Charles D.; Martinez, Ruben

This report documents tests conducted by Sandia National Laboratories (SNL) on behalf of the U.S. Department of State to evaluate a temporary anti-personnel (TAP) barrier system developed by Mitigation Technologies. For this, the SNL Denial and Structural Assessment department developed a test protocol for the evaluation of the TAP barrier system on the basis of deployment efficiency and barrier effectiveness against a riotous/mob attack threat. The test protocol was then executed by SNL personnel and the results of the testing are documented.

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Geomechanical Simulation of Bayou Choctaw Strategic Petroleum Reserve - Model Calibration

Park, Byoung

A finite element numerical analysis model has been constructed that consists of a realistic mesh capturing the geometries of Bayou Choctaw (BC) Strategic Petroleum Reserve (SPR) site and multi - mechanism deformation ( M - D ) salt constitutive model using the daily data of actual wellhead pressure and oil - brine interface. The salt creep rate is not uniform in the salt dome, and the creep test data for BC salt is limited. Therefore, the model calibration is necessary to simulate the geomechanical behavior of the salt dome. The cavern volumetric closures of SPR caverns calculated from CAVEMAN are used for the field baseline measurement. The structure factor, A 2 , and transient strain limit factor, K 0 , in the M - D constitutive model are used for the calibration. The A 2 value obtained experimentally from the BC salt and K 0 value of Waste Isolation Pilot Plant (WIPP) salt are used for the baseline values. T o adjust the magnitude of A 2 and K 0 , multiplication factors A2F and K0F are defined, respectively. The A2F and K0F values of the salt dome and salt drawdown skins surrounding each SPR cavern have been determined through a number of back fitting analyses. The cavern volumetric closures calculated from this model correspond to the predictions from CAVEMAN for six SPR caverns. Therefore, this model is able to predict past and future geomechanical behaviors of the salt dome, caverns, caprock , and interbed layers. The geological concerns issued in the BC site will be explained from this model in a follow - up report .

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November 2016 West Hackberry Subsidence Report

Moriarty, Dylan M.; Lord, Anna S.

Subsidence monitoring is a critical component to understanding the cavern integrity of salt storage caverns. This report looks at historical and recent data from two of the three West Hackberry dome cavern operators. DOE SPR and LA Storage are coordinating subsidence surveys to create a comprehensive understanding of ground movement above the dome. Data from annual level and rod surveys, GPS, and tiltmeter data show the sites are experiencing typical ground movement. The highest subsidence rate is seen in the middle of the DOE SPR site at just under one inch per year with less ground movement around the edge of the site. A GPS and tiltmeter instrument in the northeast areas of the DOE SPR site has not seen any trend change since the devices were installed in 2013. Comparison between recent ground movement data and historical trends suggest that there is no reason to believe that any DOE SPR or LA Storage caverns have been structurally compromised.

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Coupling MOS quantum dot and phosphorous donor qubit systems

Technical Digest - International Electron Devices Meeting, IEDM

Rudolph, Martin; Jock, Ryan M.; Jacobson, Noah T.; Wendt, Joel R.; Pluym, Tammy; Dominguez, Jason; Ten Eyck, Gregory A.; Manginell, Ronald; Lilly, Michael; Carroll, M.S.; Harvey-Collard, P.

Si-MOS based QD qubits are attractive due to their similarity to the current semiconductor industry. We introduce a highly tunable MOS foundry compatible qubit design that couples an electrostatic quantum dot (QD) with an implanted donor. We show for the first time coherent two-axis control of a two-electron spin logical qubit that evolves under the QD-donor exchange interaction and the hyperfine interaction with the donor nucleus. The two interactions are tuned electrically with surface gate voltages to provide control of both qubit axes. Qubit decoherence is influenced by charge noise, which is of similar strength as epitaxial systems like GaAs and Si/SiGe.

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Systems Engineering Model for ART Energy Conversion

Mendez, Carmen M.; Rochau, Gary E.; Wilson, Mollye

The near-term objective of the EC team is to establish an operating, commercially scalable Recompression Closed Brayton Cycle (RCBC) to be constructed for the NE - STEP demonstration system (demo) with the lowest risk possible. A systems engineering approach is recommended to ensure adequate requirements gathering, documentation, and mode ling that supports technology development relevant to advanced reactors while supporting crosscut interests in potential applications. A holistic systems engineering model was designed for the ART Energy Conversion program by leveraging Concurrent Engineering, Balance Model, Simplified V Model, and Project Management principles. The resulting model supports the identification and validation of lifecycle Brayton systems requirements, and allows designers to detail system-specific components relevant to the current stage in the lifecycle, while maintaining a holistic view of all system elements.

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Understanding the reliability of solder joints used in advanced structural and electronics applications: Part 1 - Filler metal properties and the soldering process

Welding Journal

Vianco, Paul T.

Soldering technology has made tremendous strides in the past half-century. Whether structural or electronic, all solder joints must provide a level of reliability that is required by the application. This Part 1 report examines the effects of filler metal properties and soldering process on joint reliability. Solder alloy composition must have the appropriate melting and mechanical properties that suit the product's assembly process(es) and use environment. The filler metal must also optimize solderability (wetting-and-spreading) to realize the proper joint geometry. Here, the soldering process also affects joint reliability. The choice of flux and thermal profile support the solderability performance of the molten filler metal to successfully fill the gap and complete the fillet.

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Cloud Computing for Complex Performance Codes

Appel, Gordon J.; Hadgu, Teklu; Klein, Brandon; Miner, John G.

This report describes the use of cloud computing services for running complex public domain performance assessment problems. The work consisted of two phases: Phase 1 was to demonstrate complex codes, on several differently configured servers, could run and compute trivial small scale problems in a commercial cloud infrastructure. Phase 2 focused on proving non-trivial large scale problems could be computed in the commercial cloud environment. The cloud computing effort was successfully applied using codes of interest to the geohydrology and nuclear waste disposal modeling community.

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Results 37401–37600 of 99,299
Results 37401–37600 of 99,299