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Examining Efficacy of Strategic Stability in South Asia: An Analysis

Sahgal, Brig A.

This paper highlights how, in the backdrop of prevalent tensions between India and Pakistan, deterrence stability is endangered even when overall strategic stability prevails. Unresolved legacy issues including an outstanding boundary dispute, conflict over Kashmir, and terrorism mar India-Pakistan relations. Variables undermining the prospects for long term peace, among others, include growing mutual mistrust, the proxy war that India believes is state perpetrated, increasing conventional asymmetry, rapid advancement in weapon technologies, growing size of nuclear arsenals, doctrinal mismatch and above all, bilateral gridlock in confidence building measures and arms control measures.

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TYPE SAND Report YEAR 2018
DOIOSTI

Discharge Permit DP-1845 Quarterly Report (July — September 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 the 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 July 1 through September 30, 2018. The report is due to NMED GWQB by February 1, 2019.

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TYPE Other Report YEAR 2018
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Environmental Restoration Operations Consolidated Quarterly Report (July — September 2018)

Cochran, John R.

This Sandia National Laboratories, New Mexico Environmental Restoration Operations (ER) Consolidated Quarterly Report (ER Quarterly Report) fulfills all quarterly reporting requirements set forth in the Compliance Order on Consent. Table I-1 lists the six sites remaining in the corrective action process. This edition of the ER Quarterly Report does not include Section II "Perchlorate Screening Quarterly Groundwater Monitoring Report" because no groundwater samples were analyzed for perchlorate during this reporting period. Additionally, Section III is not included in this edition of the ER Quarterly Report because there is no detailed Technical Area-V Groundwater information to present.

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TYPE Other Report YEAR 2018
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NSRD-16: Computational Capability to Substantiate DOE-HDBk-3010 Data

Bays, Nathan R.; Bignell, John; San LeSan; Dingreville, Remi P.M.; Gilkey, Lindsay N.; Gordon, Natalie; Fascitelli, Dominic G.

Safety basis analysts throughout the U.S. Department of Energy (DOE) complex rely heavily on the information provided in the DOE Handbook, DOE-HDBK-3010, Airborne Release Fractions/Rates and Respirable Fractions for Nonreactor Nuclear Facilities, to determine radionuclide source terms from postulated accident scenarios. In calculating source terms, analysts tend to use the DOE Handbook's bounding values on airborne release fractions (ARFs) and respirable fractions (RFs) for various categories of insults (representing potential accident release categories). This is typically due to both time constraints and the avoidance of regulatory critique. Unfortunately, these bounding ARFs/RFs represent extremely conservative values. Moreover, they were derived from very limited small-scale bench/laboratory experiments and/or from engineered judgment. Thus, the basis for the data may not be representative of the actual unique accident conditions and configurations being evaluated. The goal of this research is to develop a more accurate and defensible method to determine bounding values for the DOE Handbook using state-of-art multi-physics-based computer codes. This enables us to better understand the fundamental physics and phenomena associated with the types of accidents in the handbook. In this fourth year, we improved existing computational capabilities to better model fragmentation situations to capture small fragments during an impact accident. In addition, we have provided additional new information for various sections of Chapters 4 and 5 of the Handbook on free fall powders and impacts of solids, and have provided the damage ratio simulations for containers (7A drum and standard waste box) for various drops and impact scenarios. Thus, this work provides a low-cost method to establish physics-justified safety bounds by considering specific geometries and conditions that may not have been previously measured and/or are too costly to perform during an experiment.

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TYPE SAND Report YEAR 2018
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Approximating Two-Stage Chance-Constrained Programs with Classical Probability Bounds

Optimization Letters

Singh, Bismark; Watson, Jean-Paul

We consider a joint-chance constraint (JCC) as a union of sets, and approximate this union using bounds from classical probability theory. When these bounds are used in an optimization model constrained by the JCC, we obtain corresponding upper and lower bounds on the optimal objective function value. We compare the strength of these bounds against each other under two different sampling schemes, and observe that a larger correlation between the uncertainties tends to result in more computationally challenging optimization models. We also observe the same set of inequalities to provide the tightest upper and lower bounds in our computational experiments.

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TYPE Journal Article YEAR 2018
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MueLu User's Guide

Berger-Vergiat, Luc; Glusa, Christian; Hu, Jonathan J.; Siefert, Christopher; Tuminaro, Raymond S.; Mayr, Matthias; Prokopenko, Andrey; Wiesner, Tobias

This is the official user guide for MUELU multigrid library in Trilinos version 12.13 (Dev). This guide provides an overview of MUELU, its capabilities, and instructions for new users who want to start using MUELU with a minimum of effort. Detailed information is given on how to drive MUELU through its XML interface. Links to more advanced use cases are given. This guide gives information on how to achieve good parallel performance, as well as how to introduce new algorithms Finally, readers will find a comprehensive listing of available MUELU options. Any options not documented in this manual should be considered strictly experimental.

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TYPE SAND Report YEAR 2018
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Evaluation of High Temperature Plastics as a Ceramic Replacement

Redline, Erica M.; Dial, Brent E.; Stavig, Mark E.; Sawyer, Patricia S.; Miller, Lance L.

This report describes the 2015-2017 fiscal year research efforts to evaluate high temperature plastics as replacement materials for ceramics in electrical contact assemblies. The main objective of this work was to assess the feasibility of replacing existing high-price ceramic inserts with a polymeric material. Current ceramic parts are expensive due to machining costs and can suffer brittle failure. Therefore, replacing the ceramic with a more cost-effective material — in this case a plastic — is highly desirable. Not only are plastics easier to process, but they can also eliminate final tooling and are less brittle than ceramics. This effort used a three-phase approach: selection of appropriate materials determined by a comprehensive literature review, performance of an initial thermal stability screening, understanding of aging behavior under normal and off-normal conditions, and evaluation of performance at elevated temperatures. Two polymers were determined to meet the desired criteria: polybenzimidazole, and Vespel® SP-1 polyimide. Polymer derived ceramics may also be useful but will require further development of molding capabilities that were beyond the scope of this program.

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TYPE SAND Report YEAR 2018
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Program Fuzzing on High Performance Computing Resources

Cioce, Christian R.; Loffredo, Daniel G.; Salim, Nasser J.

American Fuzzy Lop (AFL) is an evolutionary fuzzer that is strategically implemented as a tool for discovering bugs in software during vulnerability research. This work seeks to understand how to best implement AFL on the High-Performance Computing resources available on the unclassified network at Sandia National Laboratories. We investigate various methods of executing AFL, requesting varying numbers of tasks on single compute nodes with 36 physical cores and 72 total threads. A Python script called Blue Claw is presented as an automated testbed generator tool to assist in the tedious process of creating and executing experiments of any scale and duration.

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TYPE SAND Report YEAR 2018
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Results 27601–27800 of 101,000
Results 27601–27800 of 101,000
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