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An introduction to developing GitLab/Jacamar runner analyst centric workflows at Sandia

Robinson, Allen C.; Swan, Matthew S.; Harvey, Evan C.; Klein, Brandon; Lawson, Gary; Milewicz, Reed M.; Bays, Nathan R.; Schmitz, Mark E.; Warnock, Scott A.

This document provides very basic background information and initial enabling guidance for computational analysts to develop and utilize GitOps practices within the Common Engineering Environment (CEE) and High Performance Computing (HPC) computational environment at Sandia National Laboratories through GitLab/Jacamar runner based workflows.

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Node Monitoring as a Fault Detection Countermeasure against Information Leakage within a RISC-V Microprocessor

Cryptography

Bays, Nathan R.; Joseph, Jithin; Mannos, Tom J.; Dziki, Brian

Advanced, superscalar microprocessors ((Formula presented.)) are highly susceptible to wear-out failures because of their highly complex, densely packed circuit structure and extreme operational frequencies. Although many types of fault detection and mitigation strategies have been proposed, none have addressed the specific problem of detecting faults that lead to information leakage events on I/O channels of the (Formula presented.). Information leakage can be defined very generally as any type of output that the executing program did not intend to produce. In this work, we restrict this definition to output that represents a security concern, and in particular, to the leakage of plaintext or encryption keys, and propose a counter-based countermeasure to detect faults that cause this type of leakage event. Fault injection (FI) experiments are carried out on two RISC-V microprocessors emulated as soft cores on a Xilinx multi-processor System-on-chip (MPSoC) FPGA. The (Formula presented.) designs are instrumented with a set of counters that records the number of transitions that occur on internal nodes. The transition counts are collected from all internal nodes under both fault-free and faulty conditions, and are analyzed to determine which counters provide the highest fault coverage and lowest latency for detecting leakage faults. We show that complete coverage of all leakage faults is possible using only a single counter strategically placed within the branch compare logic of the (Formula presented.).

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Inspecta Annual Technical Report

Smartt, Heidi A.; Coram, Jamie L.; Dorawa, Sydney; Bays, Nathan R.; Honnold, Philip; Kakish, Zahi; Pickett, Chris; Shoman, Nathan; Spence, Katherine

Sandia National Laboratories (SNL) is designing and developing an Artificial Intelligence (AI)-enabled smart digital assistant (SDA), Inspecta (International Nuclear Safeguards Personal Examination and Containment Tracking Assistant). The goal is to provide inspectors an in-field digital assistant that can perform tasks identified as tedious, challenging, or prone to human error. During 2021, we defined the requirements for Inspecta based on reviews of International Atomic Energy Agency (IAEA) publications and interviews with former IAEA inspectors. We then mapped the requirements to current commercial or open-source technical capabilities to provide a development path for an initial Inspecta prototype while highlighting potential research and development tasks. We selected a highimpact inspection task that could be performed by an early Inspecta prototype and are developing the initial architecture, including hardware platform. This paper describes the methodology for selecting an initial task scenario, the first set of Inspecta skills needed to assist with that task scenario and finally the design and development of Inspecta’s architecture and platform.

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Evaluation of COTS Electronics by Power Spectrum Analysis and Multivariate Data Analysis

Dejong, Stephanie; Multari, Rosalie A.; Bays, Nathan R.; Tangyunyong, Paiboon

Power spectrum analysis (PSA) is a fast, non-destructive, sensitive method for examining commercial off-the-shelf ( COTS ) electronic components. These features make PSA attractive for both component screening and surveillance in support of component reliability efforts. Current analysis methods limit the utility of PSA due to the need to manually examine the results of analysis to identify anomalous parts. This study demonstrates the development and application of a workflow to automate the screening of COTS electronic components. Further, this study demonstrates the use of multivariate algorithms to assess aging of Zener diodes. These workflows can be readily extended to other components, combining the benefits of PSA and multivariate analysis to screen and evaluate COTS electronic components.

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Alpert, Bradley; Becker, Daniel; Bennett, Douglas; Doriese, W.; Durkin, Malcolm; Fowler, Joseph; Gard, Johnathon; Imrek, Jozsef; Levine, Zachary; Mates, John; Miaja-Avila, Luis; Morgan, Kelsey; Nakamura, Nathan; O'Neil, Galen; Ortiz, Nathan; Reintsema, Carl; Schmidt, Daniel; Swetz, Daniel; Szypryt, Paul; Ullom, Joel; Vale, Leila; Weber, Joel; Wessels, Abigail; Dagel, Amber L.; Dalton, Gabriella; Bays, Nathan R.; Jimenez, Edward S.; Mcarthur, Daniel; Thompson, Kyle R.; Walker, Christopher; Wheeler, Jason; Ablerto, Julien; Griveau, Damien; Silvent, Jeremie

Abstract not provided.

Sierra/SD - How To Manual - 5.10

Crane, Nathan K.; Day, David M.; Dohrmann, Clark R.; Stevens, Brian; Lindsay, Payton; Plews, Julia A.; Vo, Johnathan; Bunting, Gregory; Joshi, Sidharth S.; Bays, Nathan R.; Chen, Mark J.Y.; Pepe, Justin

The How To Manual supplements the User’s Manual and the Theory Manual. The goal of the How To Manual is to reduce learning time for complex end to end analyses. These documents are intended to be used together. See the User’s Manual for a complete list of the options for a solution case. All the examples are part of the Sierra/SD test suite. Each runs as is. The organization is similar to the other documents: How to run, Commands, Solution cases, Materials, Elements, Boundary conditions, and then Contact. The table of contents and index are indispensable. The Geometric Rigid Body Modes section is shared with the Users Manual.

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Uncertainty and Sensitivity Analysis Methods and Applications in the GDSA Framework (FY2022)

Swiler, Laura P.; Basurto, Eduardo; Brooks, Dusty M.; Eckert, Aubrey; Leone, Rosemary C.; Mariner, Paul E.; Portone, Teresa; Bays, Nathan R.

The Spent Fuel and Waste Science and Technology (SFWST) Campaign of the U.S. Department of Energy (DOE) Office of Nuclear Energy (NE), Office of Fuel Cycle Technology (FCT) is conducting research and development (R&D) on geologic disposal of spent nuclear fuel (SNF) and high-level nuclear waste (HLW). Two high priorities for SFWST disposal R&D are design concept development and disposal system modeling. These priorities are directly addressed in the SFWST Geologic Disposal Safety Assessment (GDSA) control account, which is charged with developing a geologic repository system modeling and analysis capability, and the associated software, GDSA Framework, for evaluating disposal system performance for nuclear waste in geologic media. GDSA Framework is supported by SFWST Campaign and its predecessor the Used Fuel Disposition (UFD) campaign.

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A heteroencoder architecture for prediction of failure locations in porous metals using variational inference

Computer Methods in Applied Mechanics and Engineering

Bridgman, Wyatt; Zhang, Xiaoxuan; Teichert, Greg; Khalil, Mohammad; Garikipati, Krishna; Bays, Nathan R.

In this work we employ an encoder–decoder convolutional neural network to predict the failure locations of porous metal tension specimens based only on their initial porosities. The process we model is complex, with a progression from initial void nucleation, to saturation, and ultimately failure. The objective of predicting failure locations presents an extreme case of class imbalance since most of the material in the specimens does not fail. In response to this challenge, we develop and demonstrate the effectiveness of data- and loss-based regularization methods. Since there is considerable sensitivity of the failure location to the particular configuration of voids, we also use variational inference to provide uncertainties for the neural network predictions. We connect the deterministic and Bayesian convolutional neural network formulations to explain how variational inference regularizes the training and predictions. We demonstrate that the resulting predicted variances are effective in ranking the locations that are most likely to fail in any given specimen.

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Results 451–475 of 2,510
Results 451–475 of 2,510
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