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Quantifying Uncertainty in Emulations (LDRD Report)

Crussell, Jonathan; Brown, Aaron; Jennings, J.K.; Kavaler, David M.; Kroeger, Thomas; Phillips, Cynthia A.

This report summarizes the work performed under the project “Quantifying Uncertainty in Emulations.” Emulation can be used to model real-world systems, typically using virtualization to run the real software on virtualized hardware. Emulations are increasingly used to answer mission-oriented questions, but how well they represent the real-world systems is still an open area of research. The goal of the project was to quantify where and how emulations differ from the real world. To do so, we ran a representative workload on both, and collected and compared metrics to identify differences. We aimed to capture behaviors, rather than performance, differences as the latter is more well-understood in the literature.

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TYPE SAND Report YEAR 2019
DOIOSTI

Energy Storage Financing: Advancing Contracting in Energy Storage

Baxter, Richard

The lack of standard financing contracts and supporting documents is inhibiting the growth of the energy storage industry. A number of firms are actively developing proprietary contract structures, resulting in a variety of unique attributes. This leaves the market disjointed for 3rd party financing groups looking to scale their lending. Lack of commonality and harmonization between developer and lenders raises project execution costs and causes delays in financing. Of special concern, projects based on emerging technologies are finding an increasing uphill climb for equal consideration by developers and lenders, leaving their potential commercialization in peril. This study will evaluate the development of standardi7ed contracts to reduce the cost and contract approval time, learning from success in renewable energy project development. The goal of this study is to determine the key requirements for standard contracts in the emerging energy storage market, and suggest avenues for possible industry led development.

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TYPE SAND Report YEAR 2019
DOIOSTI

Autonomy for Hypersonics Mission Campaign (A4H)

Chavez, Jon

A4H is developing autonomous hypersonic flight vehicles that can intelligently navigate, guide, and control themselves and home-in on targets. Autonomous systems are characterized by the use of closed-loop SENSE-THINK-ACT operations to achieve their desired goals. Closing the SENSE-THINK-ACT loop onboard these systems will provide an improved ability to engage diverse targets in contested environments.

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TYPE Other Report YEAR 2019
DOIOSTI

SPARR: Spiking/Processing Array for Wide Dynamic Range and High Resolution Photonic Sensing

Hays, Park E.; Kagie, Matthew J.; Karelitz, David B.; Kay, Randolph (Rex); Mincey, John; Woods, Mark C.

The Spiking/Processing Array (spARR) is a novel photonic focal plane that uses pixels which generate electronic spikes autonomously and without a clock. These spikes feed into a network of digital asynchronous processing elements or DAPES. By building a useful assemblage of DAPES, and connecting them together in the correct way, sophisticated signal processing can be accomplished within the focal plane. Autonomous self-resetting pixels (AsP) enable SPARR to generate electronic response with very small signals--as little as a single photon in the case of Geiger mode avalanche photodiodes to as few as several hundred photons for in-cmos photodetectors. These spiking pixels enable fast detector response, but do not draw as much continuous power as synchronous clocked designs. The spikes emitted by the pixels all have the same magnitude, the information from the scene is effectively encoded into the rate of spikes and the time at which the spike is emitted. The spiking pixels, having converted incident light into electronic spikes, supply the spikes to a network of digital asynchronous processors. These are small state machines which respond to the spikes arriving at their input ports by either remaining unchanged or updating their internal state and possibly emitting a spike on one or more output ports. We show a design that accomplishes the sophisticated signal processing of a Haar spatial wavelet transform with spatial-spectral whitening. We furthermore show how this design results in a data streams which support imaging and transient optical source detection. Two simulators support this analysis: SPICE and sparrow. The CMOS SPICE simulator Cadence provides accurate CMOs design with accounting for effects of circuit parasitics throughout layout, accurate timing, and accurate energy consumption estimates. To more rapidly assess larger networks with more pixels, sparrow is a custom discrete event simulator that supports the non-homogeneous Poisson processes that lie behind photoelectric interaction. Sparrow is a photon-exact simulator that nevertheless performs SPARR system simulator for large-scale systems.

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TYPE SAND Report YEAR 2019
DOIOSTI

The dual advanced ion simultaneous implantation experiment (DAISIE) for testing plasma-facing materials

Review of Scientific Instruments

Jasica, M.J.; Kulcinski, Gerald L.; Santarius, John F.; Bonomo, Richard M.

A new dual ion beam experimental facility, the Dual Advanced Ion Simultaneous Implantation Experiment (DAISIE), has been constructed at the University of Wisconsin-Madison Inertial Electrostatic Confinement laboratory for implanting candidate plasma-facing components of multiple ion species. DAISIE is capable of implanting ions at energies from 10 kV to 50 kV, ion currents of 10 μA-950 μA, corresponding to steady-state ion fluxes of 1 × 1014 cm-2 s-1 to 1 × 1016 cm-2 s-1, incidence angles of 55°, and surface temperatures of at least 1100 °C. Improvements to the sample current and sample temperature measurement and control systems over those used in prior UW-IEC experiments have been made. Optical measurements of the spot size of the beam on samples in DAISIE are in agreement with existing measurements of the ion beam and spot size in previous UW-IEC experiments. Dual-beam operation has been confirmed with helium-deuterium ion implantations in tungsten surfaces.

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TYPE Journal Article YEAR 2019
DOIOSTIScopus

Bridging the Gap: Thermal Properties in Composites from Microscale Constituents to Macroscale Performance

Hodges, Wyatt L.; Ziade, Elbara; Bays, Nathan R.

In this work, a finite element analysis model was developed to predict the frequency domain thermal response to heat input from a gaussian heat source for arbitrary 2-dimensional geometries. The model was used for geometric parameter fitting of samples experimentally measured using Frequency Domain Thermoreflectance (FDTR). Inverse fitting was performed to on experimental data to extract characteristic geometries of samples with feature sizes smaller than the Il e 2 radius of the laser used to probe the system. Further simulations were done to demonstrate the ability of the system to detect a variety of feature types. Silicon wafers with 50 nm to 1 pm of wet thermal oxide were measured and fit. Finally, microparticles suspended in epoxy were imaged using FDTR.

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TYPE Other Report YEAR 2019
DOIOSTI

ER Consolidated Qtrly Rpt_October 2019

Leigh, Christi

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.

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TYPE Other Report YEAR 2019
DOIOSTI

Discharge Permit-1845 Quarterly Status Report October 2019

Li, Jun

Trichloroethene (TCE) and nitrate have been identified as constituents of concern in groundwater at the Sandia National Laboratories, New Mexico (SNL/NM) Technical Area (TA)-V Groundwater (TAVG) Area of Concern (AOC) based on detections above the U.S. Environmental Protection Agency (EPA) maximum contaminant levels in samples collected from monitoring wells. The maximum contaminant levels and the State of New Mexico drinking water standards, as specified in 20.6.2.3103 New Mexico Administrative Code (NMAC) for TCE and nitrate (as nitrogen) are 5 micrograms per liter (p,g/L) and 10 milligrams per liter (mg/L), respectively.

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TYPE Other Report YEAR 2019
DOIOSTI

Position and Timing Resolution Measurements ofOrganic-Glass scintillator bars for the OpticallySegmented Single-Volume Scatter Camera

Sweany, Melinda D.; Brown, Jason; Cabrera-Palmer, B.; Carlson, Joseph; Dorrill, R.; Druetzler, A.; Elam, J.; Febbraro, M.; Feng, Patrick L.; Folsom, Michael W.; Galino-Tellez, A.; Goldblum, B.; Hausladen, P.; Kaneshige, N.; Keffe, K.; Laplace, T.; Learned, J.; Mane, A.; Manfredi, Juan; Marleau, P.; Mattingly, J.; Mishra, M.; Moustafa, A.; Nattress, J.; Steele, J.; Weinfurther, K.; Ziock, K.

Abstract not provided.

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TYPE Conference Poster YEAR 2019
OSTI

Current Status of an Optically-Segmented Single-Volume Scatter Camera for Neutron Imaging

Brown, J.A.; Brubaker, Erik M.; Dorril, R.; Druetzler, A.; Elam, J.; Febbraro, M.; Feng, Patrick L.; Folsom, Michael W.; Galino-Tellez, A.; Goldblum, B.L.; Hausladen, P.; Kaneshige, N.; Keffe, K.; Laplace, T.A.; Learned, J.G.; Mane, A.; Manfredi, J.; Marleau, Peter; Mattingly, J.; Mishra; Almanza-Madrid, Rene A.; Moustafa, A.; Nattress, J.; Steele, J.; Sweany, Melinda D.; Weinfurther, K.; Ziock, K.

Abstract not provided.

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TYPE Conference Poster YEAR 2019
OSTI

Tribal Colleges and Universities/American Indian Higher Education Consortium Advanced Manufacturing Technical Assistance Project

Atcitty, Stanley

The National Nuclear Security Agency (NNSA) created a Minority Serving Institution Partnership Plan (MSIPP) to 1) align investments in a university capacity and workforce development with the NNSA mission to develop the needed skills and talent for NNSA's enduring technical workforce at the laboratories and production plants, and 2) to enhance research and education at underrepresented colleges and universities. Out of this effort, MSIPP launched a new program in early FY17 focused on Tribal Colleges and Universities (TCUs). The following report summarizes the project focus and status updates during this reporting period.

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TYPE Other Report YEAR 2019
DOIOSTI

A New Method to Contain Molten Corium in Catastrophic Nuclear Reactor Accidents

Bays, Nathan R.; Wang, Yifeng; Rao, Rekha R.; Kucala, Alec; Ross, Kyle; Kruichak-Duhigg, Jessica N.; Chavez, William R.

The catastrophic nuclear reactor accident at Fukushima damaged public confidence in nuclear energy and a demand for new engineered safety features that could mitigate or prevent radiation releases to the environment in the future. We have developed a novel use of sacrificial material (SM) to prevent the molten corium from breaching containment during accidents as well as a validated, novel, high-fidelity modeling capability to design and optimize the proposed concept. Some new reactor designs employ a core catcher and a SM, such as ceramic or concrete, to slow the molten corium and avoid the breach of the containment. However, existing reactors cannot easily be modified to include these SMs but could be modified to allow injectable cooling materials (current designs are limited to water). The SM proposed in this Laboratory Development Research and Development (LDRD) project is based on granular carbonate minerals that can be used in existing light water reactor plants. This new SM will induce an endothermic reaction to quickly freeze the corium in place, with minimal hydrogen explosion and maximum radionuclide retention. Because corium spreading is a complex process strongly influenced by coupled chemical reactions (with underlying containment material and especially with the proposed SM), decay heat and phase change. No existing tool is available for modeling such a complex process. This LDRD project focused on two research areas: experiments to demonstrate the feasibility of the novel SM concept, and modeling activities to determine the potential applications of the concept to actual nuclear plants. We have demonstrated small-scale to large-scaled experiments using lead oxide (Pb0) as surrogate for molten corium, which showed that the reaction of the SM with molten Pb0 results in a fast solidification of the melt and the formation of open pore structures in the solidified Pb0 because of CO2 released from the carbonate decomposition.

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TYPE SAND Report YEAR 2019
DOIOSTI

Pileup Calculations for GADRAS

Mitchell, Dean J.; Enghauser, Michael W.; Thoreson, Gregory

This report describes how random pileup calculations are performed by the Gamma Detector Response and Analysis Software (GADRAS) Version 19.1. The computational approach and examples are presented for gamma-ray detectors with and without pileup rejectors. This pileup algorithm executes more quickly and the results are more accurate than previous versions of GADRAS. The detector response function can be refined to characterize distortions in peak shapes that occur at high-count rates. The empirical refinement can also be applied to describe the response of partially-effective pileup rejectors. Implications are discussed for the analysis of both static measurements and dynamic collections of the type acquired with radiation portals. ACKNOWLEDGEMENTS This work was funded by the Defense Threat Reduction Agency (DTRA) and the Department of Homeland Security (DHS) Counter Weapons of Mass Destruction (CWMD) office.

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TYPE SAND Report YEAR 2019
DOIOSTI
Results 22201–22400 of 101,000
Results 22201–22400 of 101,000
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