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Three-Dimensional Electromagnetic High Frequency Axisymmetric Cavity Scars

Warne, Larry K.; Jorgenson, Roy E.

This report examines the localization of high frequency electromagnetic fields in three-dimensional axisymmetric cavities along periodic paths between opposing sides of the cavity. The cases where these orbits lead to unstable localized modes are known as scars. This report treats both the case where the opposing sides, or mirrors, are convex, where there are no interior foci, and the case where they are concave, leading to interior foci. The scalar problem is treated first but the approximations required to treat the vector field components are also examined. Particular attention is focused on the normalization through the electromagnetic energy theorem. Both projections of the field along the scarred orbit as well as point statistics are examined. Statistical comparisons are made with a numerical calculation of the scars run with an axisymmetric simulation. This axisymmetric case forms the opposite extreme (where the two mirror radii at each end of the ray orbit are equal) from the two-dimensional solution examined previously (where one mirror radius is vastly different from the other). The enhancement of the field on the orbit axis can be larger here than in the two-dimensional case.

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TYPE SAND Report YEAR 2014
DOIOSTI

Biosecurity management recommendations for rinderpest laboratories

Brodsky, Benjamin H.; Caskey, Susan; Arndt, William

Rinderpest is a virus that can affect cattle and other even toes ungulates; evidence of outbreaks from over 10,000 years ago highlights the potential impact of this virus. During the 18th century, Rinderpest caused huge losses in cattle throughout Europe. Starting in the mid 1900’s vaccination efforts seemed feasible and work was initiated to vaccinate large populations of cattle. Walter Plowright received numerous awards for updating the Rinderpest vaccine which many believed would be the key to eradication. Vaccination of the disease lead to a massive drop in outbreaks and the last confirmed case of Rinderpest in Asia was in 2000 and in Africa in 2001.1 At this point, Rinderpest has been declared eradicated from nature. However, stocks of the virus are still in many laboratories.2 Rinderpest was investigated as a biological weapon agent during the Second World War. However, following WWII, rinderpest was not considered a high risk as a biological weapon as there was no direct military advantage. Now, with the concern of the use of biological agents as weapons in acts of terrorism, concern regarding rinderpest has resurfaced. Since the eradication of this virus, cattle populations are highly susceptibility to the virus and the economic impacts would be significant. This paper will discuss the specific nature of the terrorism risks associated with rinderpest; and based upon those risks provide recommendations regarding biosecurity management. The biosecurity management measures will be defined in a manner to align with the CWA 15793: the laboratory biorisk management document.

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TYPE Other Report YEAR 2014
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Search for Majorana fermions in topological superconductors

Pan, Wei; Shi, Xiaoyan; Hawkins, Samuel D.; Klem, John F.

The goal of this project is to search for Majorana fermions (a new quantum particle) in a topological superconductor (a new quantum matter achieved in a topological insulator proximitized by an s-wave superconductor). Majorana fermions (MFs) are electron-like particles that are their own anti-particles. MFs are shown to obey non-Abelian statistics and, thus, can be harnessed to make a fault-resistant topological quantum computer. With the arrival of topological insulators, novel schemes to create MFs have been proposed in hybrid systems by combining a topological insulator with a conventional superconductor. In this LDRD project, we will follow the theoretical proposals to search for MFs in one-dimensional (1D) topological superconductors. 1D topological superconductor will be created inside of a quantum point contact (with the metal pinch-off gates made of conventional s-wave superconductors such as niobium) in a two-dimensional topological insulator (such as inverted type-II InAs/GaSb heterostructure).

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TYPE SAND Report YEAR 2014
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MAQ Analysis_Template

Draelos, Laura D.

This evaluation is based on the latest information available in the Chemical Information System (CIS). Some of the information contained in CIS may not be accurate, but this evaluation will indicate the overall hazardous material Maximum Allowable Quantity (MAQ) situation in the building. Use this information to author findings in the Building’s Fire Protection Assessment.

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TYPE Other Report YEAR 2014
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Dish Stirling High Performance Thermal Storage FY14Q4 Quad Chart

Andraka, Charles E.

The goals of this project are to demonstrate the feasibility of significant thermal storage for dish stirling systems to leverage their existing high performance to greater capacity; demonstrate key components of a latent storage and transport system enabling on-dish storage with low energy losses; and provide a technology path to a 25kWe system with 6 hours of storage.

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TYPE Other Report YEAR 2014
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Update of the Used Fuel Dispositon Campaign Implementation Plan

Mcmahon, Kevin A.; Bragg-Sitton, Shannon; Mackinnon, Robert J.; Saltzstein, Sylvia J.; Sorenson, Ken B.; Swift, Peter; Birkholzer, Jens T.

This Update to the Used Fuel Disposition Campaign Implementation Plan provides summary level detail describing how the Used Fuel Disposition Campaign (UFDC) supports achievement of the overarching mission and objectives of the Department of Energy Office of Nuclear Energy Fuel Cycle Technologies Program, building on work completed in this area since 2009. This implementation plan begins with the assumption of target dates that are set out in the January 2013 DOE Strategy for the Management and Disposal of Used Nuclear Fuel and High-Level Radioactive Waste (http://energy.gov/downloads/strategy-management-and-disposal-used-nuclearfuel- and-high-level-radioactive-waste). These target dates and goals are summarized in section III. This implementation plan will be maintained as a living document and will be updated as needed in response to available funding and progress in the Used Fuel Disposition Campaign and the Fuel Cycle Technologies Program.

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TYPE Other Report YEAR 2014
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Using High Performance Computing to Examine the Processes of Neurogenesis Underlying Pattern Separation and Completion of Episodic Information

Aimone, James B.; Bernard, Michael; Vineyard, Craig M.; Verzi, Stephen J.

Adult neurogenesis in the hippocampus region of the brain is a neurobiological process that is believed to contribute to the brain's advanced abilities in complex pattern recognition and cognition. Here, we describe how realistic scale simulations of the neurogenesis process can offer both a unique perspective on the biological relevance of this process and confer computational insights that are suggestive of novel machine learning techniques. First, supercomputer based scaling studies of the neurogenesis process demonstrate how a small fraction of adult-born neurons have a uniquely larger impact in biologically realistic scaled networks. Second, we describe a novel technical approach by which the information content of ensembles of neurons can be estimated. Finally, we illustrate several examples of broader algorithmic impact of neurogenesis, including both extending existing machine learning approaches and novel approaches for intelligent sensing.

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TYPE SAND Report YEAR 2014
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Shock compression experiments on Lithium Deuteride single crystals

Knudson, Marcus D.; Desjarlais, Michael P.; Lemke, Raymond W.

S hock compression exper iments in the few hundred GPa (multi - Mabr) regime were performed on Lithium Deuteride (LiD) single crystals . This study utilized the high velocity flyer plate capability of the Sandia Z Machine to perform impact experiments at flyer plate velocities in the range of 17 - 32 km/s. Measurements included pressure, density, and temperature between %7E200 - 600 GPa along the Principal Hugoniot - the locus of end states achievable through compression by large amplitude shock waves - as well as pressure and density of re - shock states up to %7E900 GPa . The experimental measurements are compared with recent density functional theory calculations as well as a new tabular equation of state developed at Los Alamos National Labs.

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TYPE SAND Report YEAR 2014
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Hybrid-renewable processes for biofuels production: concentrated solar pyrolysis of biomass residues

George, Anthe G.; Geier, Manfred; Dedrick, Daniel E.

The viability of thermochemically-derived biofuels can be greatly enhanced by reducing the process parasitic energy loads. Integrating renewable power into biofuels production is one method by which these efficiency drains can be eliminated. There are a variety of such potentially viable "hybrid-renewable" approaches; one is to integrate concentrated solar power (CSP) to power biomass-to-liquid fuels (BTL) processes. Barriers to CSP integration into BTL processes are predominantly the lack of fundamental kinetic and mass transport data to enable appropriate systems analysis and reactor design. A novel design for the reactor has been created that can allow biomass particles to be suspended in a flow gas, and be irradiated with a simulated solar flux. Pyrolysis conditions were investigated and a comparison between solar and non-solar biomass pyrolysis was conducted in terms of product distributions and pyrolysis oil quality. A novel method was developed to analyse pyrolysis products, and investigate their stability.

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TYPE Other Report YEAR 2014
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ER Consolidated Quarterly Report October 2014

Cochran, John R.

This Environmental Restoration Operations (ER) Consolidated Quarterly Report (ER Quarterly Report) provides the status of ongoing corrective actions and related Long- Term Stewardship (LTS) activities being implemented by Sandia National Laboratories, New Mexico (SNL/NM) ER for the April, May, and June 2014 quarterly reporting period. Section 2.0 provides the status of ER Operations activities including closure activities for the Mixed Waste Landfill (MWL), project management and site closure, and hydrogeologic characterizations. Section 3.0 provides the status of LTS activities that relate to the Chemical Waste Landfill (CWL) and the associated Corrective Action Management Unit (CAMU). Section 4.0 provides the references noted in Section I of this report.

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TYPE Other Report YEAR 2014
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Progress report of Sandia National Laboratories (SNL) contribu- tion to IAEA CRP F11016 on ?Utilization of ion accelerators for studying and modeling of radiation induced defects in semicon- ductors and insulators? 3rd RCM

Vizkelethy, Gyorgy

This report presents the results of Sandia National Laboratories’ (SNL) contribution to IAEA CRP F11016 as mostly raw data. The goal of this CRP is to study the effects of radiation on semiconductors and insulators with the emphasis on the effect of displacement damage due to MeV energy ions on the performance of semiconductor detectors and microelectronic devices. SNL is tasked with performing electrical characterization, irradiation, and IBIC, DLTS, C-­V measurements on devices used in the CRP, as well as calculating damage and ionization profiles for modeling.

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TYPE Other Report YEAR 2014
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Sampling and Filtering in Photovoltaic System Performance Monitoring

Driesse, Anton; Stein, Joshua; Riley, Daniel; Carmignani, Craig K.

The performance of photovoltaic systems must be monitored accurately to ensure profitable long-term operation. The most important signals to be measured—irradiance and temperature, as well as power, current and voltage on both DC and AC sides of the system—contain rapid fluctuations that are not observable by typical monitoring systems. Nevertheless these fluctuations can affect the accuracy of the data that are stored. This report closely examines the main signals in one operating PV system, which were recorded at 2000 samples per second. It analyzes the characteristics and causes of the rapid fluctuations that are found, such as line-frequency harmonics, perturbations from anti-islanding detection, MPPT searching action and others. The operation of PV monitoring systems is then simulated using a wide range of sampling intervals, archive intervals and filtering options to assess how these factors influence data accuracy. Finally several potential sources of error are discussed with real-world examples.

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TYPE SAND Report YEAR 2014
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LDRD Report: Scheduling Irregular Algorithms

Boman, Erik G.

This LDRD project was a campus exec fellowship to fund (in part) Donald Nguyen’s PhD research at UT-Austin. His work has focused on parallel programming models, and scheduling irregular algorithms on shared-memory systems using the Galois framework. Galois provides a simple but powerful way for users and applications to automatically obtain good parallel performance using certain supported data containers. The naïve user can write serial code, while advanced users can optimize performance by advanced features, such as specifying the scheduling policy. Galois was used to parallelize two sparse matrix reordering schemes: RCM and Sloan. Such reordering is important in high-performance computing to obtain better data locality and thus reduce run times.

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TYPE Other Report YEAR 2014
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Results 51201–51300 of 99,299
Results 51201–51300 of 99,299