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Construction of tolerance bounds for a multivariate response associated with a covariate: A case study

arXiv.org Repository

Thomas, Edward V.; King, Caleb; Cap, Jerome S.; Montoya, Angela C.

The purpose of this research is to describe and illustrate practical methods that can be used to construct tolerance bounds for a multivariate measurement associated with a covariate. These methods rely on principal components analysis and the parametric bootstap. The methods are illustrated with an example in which the vibration environment experienced by a test object being carried by an aircraft (known as captive carry) is characterized.

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Nuclear-driven electron spin rotations in a single donor coupled to a silicon quantum dot

Science

Carroll, M.S.; Harvey-Collard, Patrick; Jacobson, N.T.; Rudolph, Martin; Dominguez, Jason J.; Ten Eyck, Gregory A.; Wendt, Joel R.; Pluym, Tammy; Bays, Nathan R.; Lilly, Michael P.; Pioro-Ladriere, Michel

Silicon chips hosting a single donor can be used to store and manipulate one bit of quantum information. However, a central challenge for realizing quantum logic operations is to couple donors to one another in a controllable way. To achieve this, several proposals rely on using nearby quantum dots (QDs) to mediate an interaction. In this work, we demonstrate the coherent coupling of electron spins between a single 31 P donor and an enriched 28 Si metal-oxide-semiconductor few-electron QD. We show that the electron-nuclear spin interaction on the donor can drive coherent rotations between singlet and triplet electron spin states of the QD-donor system. Moreover, we are able to tune electrically the exchange interaction between the QD and donor electrons. Furthermore, the combination of single-nucleus-driven rotations and voltage-tunable exchange provides every key element for future all-electrical control of spin qubits, while requiring only a single QD and no additional magnetic field gradients

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Contingency Contractor Optimization Tool Prototype (Phase 3 Extension- Analyst Tutorial)

Bandlow, Alisa; Gearhart, Jared L.; Jones, Katherine A.; Adair, Kristin L.; Durfee, Justin D.; Frazier, Christopher R.; Nozick, Linda

This tutorial walks the user through analysis examples using the Contingency Contractor Optimization Tool Prototype. The examples are designed to showcase key capabilities of the tool. The main goal of this tutorial is to provide examples of how to use the tool to perform analyses to those users acting in the analyst role. All examples and locations used in the prototype are fictional, but are intended to be realistic. Users reading this manual are expected to have a basic understanding and familiarity with the Contingency Contractor Optimization Tool Prototype. This tutorial includes scenarios for the occurrence of two wars, Prussia and New Granada.

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Contingency Contractor Optimization Engineering Prototype – Release 2.3 (Phase 3 Extension – Training Examples)

Bandlow, Alisa; Adair, Kristin L.; Durfee, Justin D.; Frazier, Christopher R.; Jones, Katherine A.; Gearhart, Jared L.; Nozick, Linda

This document provides training examples to provide users practice in using the tool. Detailed instructions on how to use the tool can be found in the User Manual (SAND2015-6028).The Contingency Contractor Optimization project is intended to address former Secretary Gates’ mandate in a January 2011 memo and DoDI 3020.41 by delivering a centralized strategic planning tool that allows senior decision makers to quickly and accurately assess the impacts, risks, and mitigation strategies associated with utilizing contract support. Based on an electronic storyboard prototype developed in Phase 2, the CCOT-P engineering prototype was refined in Phase 3 of the OSD ATL Contingency Contractor Optimization project to support strategic planning for contingency contractors. CCOT-P uses a model to optimize the total workforce mix by minimizing the combined total costs for the selected mission scenarios. The model will optimize the match of personnel groups (military, DoD civilian, and contractors) and capabilities to meet the mission requirements as effectively as possible, based on risk, cost, and other requirements.

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The Frequency-Coded Pulse-Burst Waveform and the Costas Sequence

Brock, Billy C.

The process of simultaneously measuring range and radial velocity with radar is accompanied by an inherent uncertainty or ambiguity in the values obtained. The choice of radar waveform allows some control over this uncertainty. This study examines the frequency-coded pulse-burst waveform as it relates to determination of the range and radial velocity of a moving target. The radar ambiguity function and the matched-filter response are presented for a certain class of frequency-coded pulse bursts, in which each subpulse contains exactly an integer number of cycles. The study is specialized further to the examination of a pulse burst based on a special sequence of integers called a Costas sequence. The advantages and disadvantages of this special waveform are described. Results from simulated measurements are included.

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Holistic Portfolio Optimization using Directed Mutations

Henry, Stephen M.; Smith, Mark A.; Eddy, John P.

Genetic algorithms provide attractive options for performing nonlinear multi-objective combinatorial design optimization, and they have proven very useful for optimizing individual systems. However, conventional genetic algorithms fall short when performing holistic portfolio optimizations in which the decision variables also include the integer counts of multiple system types over multiple time periods. When objective functions are formulated as analytic functions, we can formally differentiate with respect to system counts and use the resulting gradient information to generate favorable mutations in the count variables. We apply several variations on this basic idea to an idealized hanging chain example to obtain >> 1000x speedups over conventional genetic algorithms in both single - and multi-objective cases. We develop a more complex example of a notional military portfolio that includes combinatorial design variables and dependency constraints between the design choices. In this case, our initial results are mixed, but many variations are still open to further research.

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Helium trapping at erbium oxide precipitates in erbium hydride

Foiles, Stephen M.; Battaile, Corbett C.

The formation of He bubbles in erbium tritides is a significant process in the aging of these materials. Due to the long-standing uncertainty about the initial nucleation process of these bubbles, there is interest in mechanisms that can lead to the localization of He in erbium hydrides. Previous work has been unable to identify nucleation sites in homogeneous erbium hydride. This work builds on the experimental observation that erbium hydrides have nano- scale erbium oxide precipitates due to the high thermodynamic stability of erbium oxide and the ubiquitous presence of oxygen during materials processing. Fundamental DFT calculations indicate that the He is energetically favored in the oxide relative to the bulk hydride. Activation energies for the motion of He in the oxide and at the oxide-hydride interface indicate that trapping is kinetically feasible. A simple kinetic Monte Carlo model is developed that demonstrates the degree of trapping of He as a function of temperature and oxide fraction.

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Automation and Database Collection and Extrapolation

Jenkins, Chris

This report highlights overall design consideration regarding automation and database collection and extrapolation prototype for Farmpod, LLC. There are potentially many combinations of software, hardware, and networking which suffices for the requirements. For this report, we suggest a Raspberry Pi 2 Model B for the hardware. We suggest the Mako application server for the user interface and RPIO python modules for automated software processes. At the present moment, security is not a major concern, but should be addressed during the initial design phase. The software stack consists of two primary components: the automated processes and application server to implement a user interface.

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Comparison of dislocation density tensor fields derived from discrete dislocation dynamics and crystal plasticity simulations of torsion

Journal of Materials Science Research

Jones, Reese E.; Zimmerman, Jonathan A.; Po, Giacomo; Mandadapu, Kranthi

Accurate simulation of the plastic deformation of ductile metals is important to the design of structures and components to performance and failure criteria. Many techniques exist that address the length scales relevant to deformation processes, including dislocation dynamics (DD), which models the interaction and evolution of discrete dislocation line segments, and crystal plasticity (CP), which incorporates the crystalline nature and restricted motion of dislocations into a higher scale continuous field framework. While these two methods are conceptually related, there have been only nominal efforts focused at the global material response that use DD-generated information to enhance the fidelity of CP models. To ascertain to what degree the predictions of CP are consistent with those of DD, we compare their global and microstructural response in a number of deformation modes. After using nominally homogeneous compression and shear deformation dislocation dynamics simulations to calibrate crystal plasticity ow rule parameters, we compare not only the system-level stress-strain response of prismatic wires in torsion but also the resulting geometrically necessary dislocation density fields. To establish a connection between explicit description of dislocations and the continuum assumed with crystal plasticity simulations we ascertain the minimum length-scale at which meaningful dislocation density fields appear. Furthermore, our results show that, for the case of torsion, that the two material models can produce comparable spatial dislocation density distributions.

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Assessment of a Hydroxyapatite Permeable Reactive Barrier to Remediate Uranium at the Old Rifle Site Colorado

Moore, Robert C.; Szecsody, James; Rigali, Mark J.; Vermuel, Vince; Leullen, Jon

We have performed an initial evaluation and testing program to assess the effectiveness of a hydroxyapatite (Ca10(PO4)6(OH)2) permeable reactive barrier and source area treatment to decrease uranium mobility at the Department of Energy (DOE) former Old Rifle uranium mill processing site in Rifle, western Colorado. Uranium ore was processed at the site from the 1940s to the 1970s. The mill facilities at the site as well as the uranium mill tailings previously stored there have all been removed. Groundwater in the alluvial aquifer beneath the site still contains elevated concentrations of uranium, and is currently used for field tests to study uranium behavior in groundwater and investigate potential uranium remediation technologies. The technology investigated in this work is based on in situ formation of apatite in sediment to create a subsurface apatite PRB and also for source area treatment. The process is based on injecting a solution containing calcium citrate and sodium into the subsurface for constructing the PRB within the uranium plume. As the indigenous sediment micro-organisms biodegrade the injected citrate, the calcium is released and reacts with the phosphate to form hydroxyapatite (precipitate). This paper reports on proof-of-principle column tests with Old Rifle sediment and synthetic groundwater.

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Environmental Management System Objectives & Targets Results Summary - FY 2015

Vetter, Douglas W.

Sandia National Laboratories (SNL) Environmental Management System is the integrated approach for members of the workforce to identify and manage environmental risks. Each Fiscal Year (FY) SNL performs an analysis to identify environmental aspects, and the environmental programs associated with them are charged with the task of routinely monitoring and measuring the objectives and targets that are established to mitigate potential impacts of SNL's operations on the environment. An annual summary of the results achieved towards meeting established Sandia Corporation and SNL Site-specific objectives and targets provides a connection to, and rational for, annually revised environmental aspects. The purpose of this document is to summarize the results achieved and documented in FY 2015.

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Defect Characterization for Material Assurance in Metal Additive Manufacturing (FY15-0664)

Salzbrenner, Bradley; Boyce, Brad L.; Jared, Bradley H.; Rodelas, Jeffrey; Laing, John R.

No industry-wide standards yet exist for minimum properties in additively manufactured (AM) metals. While AM alloys such as 17-4 precipitation hardened stainless steel have been shown to have average properties that can be comparable to wrought or cast product, they suffer from inconsistent performance. Variability in the feedstock powder, feature sizes, thermal history, and laser performance can lead to unpredictable surface finish, chemistry, phase content, and defects. To address this issue, rapid, efficient, high-throughput mechanical testing and data analysis was developed, providing profound statistical insight into the stochastic variability in properties. With this new approach, 1000’s of comprehensive tensile tests can be performed for the cost of 10’s of conventional tests. This new high-throughput approach provides a material qualification pathway that is commensurate with the quick turn-around benefit of AM.

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Hydrogen Assisted Fracture of Stainless Steels

Sugar, Joshua D.; Somerday, Brian P.; Homer, Mark; Bays, Nathan R.; Matsuda, Junko

The Enhanced Surveillance Sub-program has an annual NNSA requirement to submit a comprehensive report on all our fiscal year activities right after the start of the next calendar year. As most of you know, we collate all of our PI task submissions into a single volume that we send to NNSA, our customers, and use for other programmatic purposes. The functional objective of this report is to formally document the purpose, status, and accomplishments and impacts of all our work. For your specific submission, please follow the instructions described below and use the template provided. These are essentially the same as was used last year. We recognize this report may also include information on specific age-related findings that you will provide again in a few months as input to the Stockpile Annual Assessment process (e.g., in the submittal of your Component Assessment Report). However, the related content of your ES AR input should provide an excellent foundation that can simply be updated as needed for your Annual Assessment input.

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Using Machine Learning in Adversarial Environments

Davis, Warren L.

Intrusion/anomaly detection systems are among the first lines of cyber defense. Commonly, they either use signatures or machine learning (ML) to identify threats, but fail to account for sophisticated attackers trying to circumvent them. We propose to embed machine learning within a game theoretic framework that performs adversarial modeling, develops methods for optimizing operational response based on ML, and integrates the resulting optimization codebase into the existing ML infrastructure developed by the Hybrid LDRD. Our approach addresses three key shortcomings of ML in adversarial settings: 1) resulting classifiers are typically deterministic and, therefore, easy to reverse engineer; 2) ML approaches only address the prediction problem, but do not prescribe how one should operationalize predictions, nor account for operational costs and constraints; and 3) ML approaches do not model attackers’ response and can be circumvented by sophisticated adversaries. The principal novelty of our approach is to construct an optimization framework that blends ML, operational considerations, and a model predicting attackers reaction, with the goal of computing optimal moving target defense. One important challenge is to construct a realistic model of an adversary that is tractable, yet realistic. We aim to advance the science of attacker modeling by considering game-theoretic methods, and by engaging experimental subjects with red teaming experience in trying to actively circumvent an intrusion detection system, and learning a predictive model of such circumvention activities. In addition, we will generate metrics to test that a particular model of an adversary is consistent with available data.

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Treatment of Oil & Gas Produced Water

Dwyer, Brian P.

Production of oil and gas reserves in the New Mexico Four Corners Region results in large volumes of "produced water". The common method for handling the produced water from well production is re-injection in regulatory permitted salt water disposal wells. This is expensive (%7E $5/bbl.) and does not recycle water, an ever increasingly valuable commodity. Previously, Sandia National Laboratories and several NM small business tested pressure driven membrane-filtration techniques to remove the high TDS (total dissolved solids) from a Four Corners Coal Bed Methane produced water. Treatment effectiveness was less than optimal due to problems with pre-treatment. Inadequate pre-treatment allowed hydrocarbons, wax and biological growth to foul the membranes. Recently, an innovative pre-treatment scheme using ozone and hydrogen peroxide was pilot tested. Results showed complete removal of hydrocarbons and the majority of organic constituents from a gas well production water. ACKNOWLEDGEMENTS This report was made possible through funding from the New Mexico Small Business Administration (NMSBA) Program at Sandia National Laboratories. Special thanks to Juan Martinez and Genaro Montoya for guidance and support from project inception to completion. Also, special thanks to Frank McDonald, the small businesses team POC, for laying the ground work for the entire project; Teresa McCown, the gas well owner and very knowledgeable- fantastic site host; Lea and Tim Phillips for their tremendous knowledge and passion in the oil & gas industry.; and Frank Miller and Steve Addleman for providing a pilot scale version of their proprietary process to facilitate the pilot testing.

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Environmental Baseline Survey for Proposed Land Use Permit Modification for Expansion of the Dynamic Explosive Test Site (DETS) 9940 Main Complex Parking Lot

Peek, Dennis W.

The approach was to perform a document search, supplemented by a visual site inspection, to identify potential environmental contamination associated with the property. Factors evaluated included hazardous substances; petroleum products and derivatives; environmental restoration sites; areas of concern; storage tanks; oil/water separators; grease traps; wash racks; waste tanks; pesticides; military munitions/ordnance; medical or bio-hazardous waste; radioactive waste; solid/municipal waste; indoor air quality; groundwater; wastewater treatment, collection, and disposal/discharge; drinking water quality; utilities; asbestos; polychlorinated biphenyls (PCBs); radon; lead-based paint; cultural resources; floodplains; and natural/biological resources.

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2014 Annual Site Environmental Report Summary Pamphlet for Sandia National Laboratories New Mexico

Griffith, Stacy

This ASER Summary Pamphlet presents the environmental protection, restoration, and monitoring programs in place at SNL/NM during calendar year 2014. It also discusses Sandia’s compliance with environmental regulations, and it highlights significant environmental program efforts and accomplishments. The environmental programs and waste management activities at SNL/NM meet or exceed the requirements of federal, state, and local environmental regulations, as well as DOE directives in the contract between Sandia and DOE. This document, prepared in accordance with and as required by DOE Order 231.1B, Environment, Safety, and Health Reporting, is a key component of DOE’s efforts to keep the public informed about environmental conditions throughout the DOE/NNSA nuclear weapons complex.

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Digital Image Correlation for Performance Monitoring

Palaviccini, Miguel; Turner, D.Z.; Herzberg, Michael

Evaluating the health of a mechanism requires more than just a binary evaluation of whether an operation was completed. It requires analyzing more comprehensive, full-field data. Health monitoring is a process of nondestructively identifying characteristics that indicate the fitness of an engineered component. In order to monitor unit health in a production setting, an automated test system must be created to capture the motion of mechanism parts in a real-time and non-intrusive manner. One way to accomplish this is by using high-speed video (HSV) and Digital Image Correlation (DIC). In this approach, individual frames of the video are analyzed to track the motion of mechanism components. The derived performance metrics allow for state-of-health monitoring and improved fidelity of mechanism modeling. The results are in-situ state-of-health identification and performance prediction. This paper introduces basic concepts of this test method, and discusses two main themes: the use of laser marking to add fiducial patterns to mechanism components, and new software developed to track objects with complex shapes, even as they move behind obstructions. Finally, the implementation of these tests into an automated tester is discussed.

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Metrics for the Complexity of Material Models

Silling, Stewart

Quantitative measures are proposed for characterizing the complexity of material models used in computational mechanics. The algorithms for evaluating these metrics operate on the mathematical equations in the model rather than a code implementation and are different from software complexity measures. The metrics do not rely on a physical understanding of the model, using instead only a formal statement of the equations. A new algorithm detects the dependencies, whether explicit or implicit, between all the variables. The resulting pattern of dependencies is expressed in a set of pathways, each of which represents a chain of dependence between the variables. These pathways provide the raw data used in the metrics, which correlate with the expected ease of understanding, coding, and applying the model. Usage of the ComplexityMetrics code is described, with examples.

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WEC-SIM Validation Testing Plan FY14 Q4

Ruehl, Kelley

The WEC-Sim project is currently on track, having met both the SNL and NREL FY14 Milestones, as shown in Table 1 and Table 2. This is also reflected in the Gantt chart uploaded to the WEC-Sim SharePoint site in the FY14 Q4 Deliverables folder. The work completed in FY14 includes code verification through code-to-code comparison (FY14 Q1 and Q2), preliminary code validation through comparison to experimental data (FY14 Q2 and Q3), presentation and publication of the WEC-Sim project at OMAE 2014 [1], [2], [3] and GMREC/METS 2014 [4] (FY14 Q3), WEC-Sim code development and public open-source release (FY14 Q3), and development of a preliminary WEC-Sim validation test plan (FY14 Q4). This report presents the preliminary Validation Testing Plan developed in FY14 Q4. The validation test effort started in FY14 Q4 and will go on through FY15. Thus far the team has developed a device selection method, selected a device, and placed a contract with the testing facility, established several collaborations including industry contacts, and have working ideas on the testing details such as scaling, device design, and test conditions.

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Analytic framework for the United States cyber deterrence strategy. Final draft, 2nd submission (20 May 2015]

Jackson, Marian C.; Blackwell, Heather; Mccann, Jennifer

If the United States (U.S.) government allows cyberattacks to continue on their current trajectory of increased frequency and effect, the bonds holding our society together will be jeopardized, potentially impacting the survival of our society as we know it. Actions must be taken not only to defend against, but also to deter future cyberattacks. To achieve a credible and actionable U.S. Cyber Deterrence Strategy, the following three lines of effort are recommended for implementation by the White House: 1. Add a sixth priority to the Obama Administration's current cyberspace priorities to state: "Advance our cyber response policies and capabilities to further protect the country's national interests by deterring attacks within cyberspace." 2. Adopt the proposed Cyber Deterrence Analytic Framework as a guide for policy makers to use when determining the appropriate response to a cyberattack. 3. Implement the proposed Presidential Policy Directive outlining the United States' deterrence policy for cyber. These recommendations for establishing a U.S. Cyber Deterrence Strategy address the following key findings: As the U.S. private sector owns and operates over 90% of all of the networks and infrastructure of cyberspace, an effective policy must be communicated clearly across the government, business enterprise, and most importantly, to the people; More so than any time in our nation's history, individuals, companies, and organizations depend on cyberspace for uses ranging from social interactions to sustaining democracy; Threats existing within the cyber domain have grown both in attack vector complexity and societal impact; and, The current Presidential Executive Orders and Policy Directives related to cyber deterrence do not include a strategy for deterring attacks. The concepts presented in this paper were derived from interviews with experts in subjects ranging from deterrence philosophy, nuclear weapons implementation, U.S. cyber operations, and U.S. cyber policy. In addition, theories on deterrence strategies are explored, ranging from the 1960s to present to develop a deterrence strategy unique to cyber. Lastly, recent examples of cyberattacks are examined to provide evidence for the need to establish consequences for those individuals or countries that continue to behave nefariously within cyberspace. To form a strong foundation for a U.S. Cyber Deterrence Strategy, the U.S. must establish and clearly articulate the consequences for nations or individuals if they choose to initiate a cyberattack on the U.S. or its national interests.

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Analysis of SNL/MSU/DOE Fatigue Database Trends for Wind Turbine Blade Materials 2010-2015

Mandell, John F.; Samborsky, Daniel D.; Miller, David A.; Agastra, Pancasatya; Sears, Aaron T.

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Results 45401–45600 of 100,993
Results 45401–45600 of 100,993
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