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Machine Learning Enabled Lineshape Analysis in Optical Two-Dimensional Coherent Spectroscopy

Conference Proceedings - Lasers and Electro-Optics Society Annual Meeting-LEOS

Titze, Michael; Namuduri, Srikanth; Li, Hebin

Although analytical solutions exist, the analysis of two-dimensional spectroscopy (2DCS) data can be tedious. A machine learning approach to analyzing 2DCS spectra is presented. We test the accuracy of the algorithm on simulated and experimental data.

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TYPE Conference Poster YEAR 2020
OSTIScopus

Survey of Current State of the Art Entity-Relation Extraction Tools

Ward, Katrina J.; Bisila, Jonathan; Cairns, Kelsey

In the area of information extraction from text data, there exists a number of tools with the capability of extracting entities, topics, and their relationships with one another from both structured and unstructured text sources. Such information has endless uses in a number of domains, however, the solutions to getting this information are still in early stages and has room for improvement. The topic has been explored from a research perspective by academic institutions, as well as formal tool creation from corporations but has not made much advancement since the early 2000's. Overall, entity extraction, and the related topic of entity linking, is common among these tools, though with varying degrees of accuracy, while relationship extraction is more difficult to find and seems limited to same sentence analysis. In this report, we take a look at the top state of the art tools currently available and identify their capabilities, strengths, and weaknesses. We explore the common algorithms in the successful approaches to entity extraction and their ability to efficiently handle both structured and unstructured text data. Finally, we highlight some of the common issues among these tools and summarize the current ability to extract relationship information.

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TYPE SAND Report YEAR 2020
DOIOSTI

Uncertainty analysis of Resource Demand Model for Covid-19

Swiler, Laura P.; Portone, Teresa; Beyeler, Walter E.

As part of the Department of Energy response to the novel coronavirus pandemic of 2020, a modeling effort was sponsored by the DOE Office of Science. One task of this modeling effort at Sandia was to develop a model to predict medical resource needs given various patient arrival scenarios. Resources needed include personnel resources (nurses, ICU nurses, physicians, respiratory therapists), fixed resources (regular or ICU beds and ventilators), and consumable resources (masks, gowns, gloves, face shields, sedatives). This report documents the uncertainty analysis that was performed on the resource model. The uncertainty analysis involved sampling 26 input parameters to the model. The sampling was performed conditional on the patient arrival streams that also were inputs to the model. These patient arrival streams were derived from various epidemiology models and had a significant effect on the projected resource needs. In this report, we document the sampling approach, the parameter ranges used, and the computational workflow necessary to perform large-scale uncertainty studies for every county and state in the United States.

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TYPE SAND Report YEAR 2020
DOIOSTI

Design Consideration for Solar Powered Wastewater Treatment Facility for Agriculture and Potable Usage on Acoma Pueblo Reservation

Arguello, Veronique M.

Environmental stewardship has long been a guiding principle among indigenous peoples. Acoma Pueblo, located approximately 45 miles west of Albuquerque, New Mexico, shares these values. They are exploring how to incorporate these values into future development projects. As such, Acoma recently created a wastewater treatment facility to provide irrigation water to nearby crops. Treatment facilities like this further sustainable practices and benefit the community but may draw power from the grid. This report looks at design considerations for possible photovoltaic utilization at the site to offset current power and monetary costs. Lessons learned from a larger, municipal wastewater treatment center will be applied with special considerations for Acoma Pueblo's values and unique wastewater treatment facility configuration.

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TYPE SAND Report YEAR 2020
DOIOSTI

Cascaded Third Harmonic Generation in Dielectric Metasurfaces

Conference Proceedings - Lasers and Electro-Optics Society Annual Meeting-LEOS

Gennaro, Sylvain D.; Addamane, Sadhvikas J.; Reno, John L.; Vabishchevich, Polina; Sinclair, Michael B.; Brener, Igal

In this work, we investigate cascaded third harmonic generation in a dielectric metasurface by exploiting high quality factor Fano resonances obtained using broken symmetry unit cells.

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TYPE Conference Poster YEAR 2020
DOIOSTIScopus

Observations Regarding Face Shield Designs Using Commonly Available Materials

Rossman, Grant A.; Avina, Isaac C.; Steinfeldt, Bradley

A Sandia COVID-19 LDRD effort, the Sandia E-PiPEline Team, systematically evaluated design options for face shields constructed from commonly available materials (CAMs). This study is not focused on face shields for medical applications, and as such, has excluded labeling and flammability considerations suggested by the FDA. Design options for face shields were analyzed with subject matter expert input considering the design's effectiveness (seal around face), reusability (compatibility with solvents, degree of inertness), producibility (ability to obtain materials, build time), cost, and comfort (fit around head, contact surface interface). Observations for the design of face shields using CAMS are provided here.

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TYPE Other Report YEAR 2020
DOIOSTI

Modular Linear Thermoviscoelastic Model

Lester, Brian T.; Long, Kevin N.

Time-dependent, viscoelastic responses of materials like polymers and glasses have long been studied. As such, a variety of models have been put forth to describe the behavior including simple rheological models (e.g. Maxwell, Kelvin), linear "fading memory" theories, and hereditary integral based linear thermal viscoelastic approaches as well as more recent nonlinear theories that are either integral, fictive temperature, or differential internal state variable based. The current work details a new LINEAR_THERMOVISCOELASTIC model that has been added to LAME. This formulation represents a viscoelastic theory that neglects some of the phenomenological details of the PEC/SPEC models in favor of efficiency and simplicity. Furthermore, this new model is a first step towards developing "modular" viscoelastic capabilities akin to those available with hardening descriptions for plasticity models in LAME. Specifically, multiple different (including user-defined) shift-factor forms are implemented with each being easily selected via parameter specification rather than requiring distinct material models.

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TYPE Other Report YEAR 2020
DOIOSTI

Observations Regarding Face Covering Designs Using Commonly Available Materials

Rossman, Grant A.; Avina, Isaac C.; Steinfeldt, Bradley

The Center for Disease Control has recommended that the public should wear cloth face coverings in public settings'. A Sandia COVID-19 LDRD effort, the Sandia E-PiPEline Team, systematically evaluated design options for face coverings constructed from commonly available materials (CAMS). The design options were analyzed with subject matter expert input considering the design's effectiveness (metric fiber density, material construction, and water saturation), reusability (degree of inertness), producibility (ability to obtain materials, build time), cost, and comfort (fit on face, breathability). Observations for the design of face coverings using CAMs are provided here.

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TYPE Other Report YEAR 2020
DOIOSTI

Why does cyber deterrence fail and when might it succeed? A framework for cyber scenario analysis

Uribe, Eva U.; Bonin, Benjamin J.; Minner, Michael; Reinhardt, Jason C.; Hammer, Ann E.; Teclemariam, Nerayo P.; Miller, Trisha H.; Forrest, Robert; Apolis, Jeffrey J.; Yang, Lynn I.

Through cyberattacks on information technology and digital communications systems, antagonists have increasingly been able to alter the strategic balance in their favor without provoking serious consequences. Conflict within and through the cyber domain is inherently different from conflict in other domains that house our critical systems. These differences result in new challenges for defending and creating resilient systems, and for deterring those who would wish to disrupt or destroy them. The purpose of this paper is to further examine the question of whether or not deterrence can be an effective strategy in cyber conflict, given our broad and varied interests in cyberspace. We define deterrence broadly as the creation of conditions that dissuade antagonists from taking unwanted actions because they believe that they will incur unacceptably high costs and/or receive insufficient benefits from taking that action. Deterrence may or may not be the most credible or effective strategy for achieving our desired end states in cybersecurity. Regardless of the answer here, however, it is important to consider why deterrence strategies might succeed under certain conditions, and to understand why deterrence is not effective within the myriad contexts that it appears fail. Deterrence remains a key component of U.S. cyber strategy, but there is little detail on how to operationalize or implement this policy, how to bring a whole-of-government and whole-of- private-sector approach to cyber deterrence, which types of antagonists can or should be deterred, and in which contexts. Moreover, discussion about how nations can and should respond to significant cyber incidents largely centers around whether or not the incident constitutes a "use of force," which would justify certain types of responses according to international law. However, we believe the "use of force" threshold is inadequate to describe the myriad interests and objectives of actors in cyberspace, both attackers and defenders. In this paper, we propose an approach to further examine if deterrence is an effective strategy and under which conditions. Our approach includes systematic analysis of cyber incident scenarios using a framework to evaluate the effectiveness of various activities in influencing antagonist behavior. While we only examine a single scenario for this paper, we propose that additional work is needed to more fully understand how various alternative thresholds constrain or unleash options for actors to influence one another's behavior in the cyber domain.

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TYPE SAND Report YEAR 2020
DOIOSTI

Cathode Modeling and Diode Performance in a Planar Geometry using Space-charge-limited Emission

Powell, Troy C.

Space-charge-limited (SCL) emission parameters are varied to study the performance effects in a planar diode using an electromagnetic particle-in-cell simulation software suite, EMPIRE. Oscillations in the simulations are found and linked to the emission parameters, namely the breakdown threshold, the emission delay time, and the current density ramp time. The oscillations are suggested to be a transverse oscillator due to the perfect magnetic conductor boundary condition in steady-state operation and the formation of a virtual cathode in the diode driven by the SCL boundary condition.

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TYPE Other Report YEAR 2020
DOIOSTI

Applying Waveform Correlation to Mining Blasts Using a Global Sparse Network

Sundermier, Amy; Tibi, Rigobert; Young, Christopher J.

Agencies that monitor for underground nuclear tests are interested in techniques that automatically characterize mining blasts to reduce the human analyst effort required to produce high-quality event bulletins. Waveform correlation is effective in finding similar waveforms from repeating seismic events, including mining blasts. We report the results of an experiment that uses waveform templates recorded by multiple International Monitoring System stations of the Comprehensive Nuclear-Test-Ban Treaty for up to 10 years prior to detect and identify mining blasts that occur during single weeks of study. We discuss approaches for template selection, threshold setting, and event detection that are specialized for mining blasts and a sparse, global network. We apply the approaches to two different weeks of study for each of two geographic regions, Wyoming and Scandinavia, to evaluate the potential for establishing a set of standards for waveform correlation processing of mining blasts that can be effective for operational monitoring systems with a sparse network. We compare candidate events detected with our processing methods to the Reviewed Event Bulletin of the International Data Centre to develop an intuition about potential reduction in analyst workload.

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TYPE SAND Report YEAR 2020
DOIOSTI
Results 17401–17500 of 99,299
Results 17401–17500 of 99,299