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Xyce™ Parallel Electronic Simulator Users' Guide, Version 6.5

Keiter, Eric R.; Aadithya, Karthik V.; Mei, Ting; Russo, Thomas V.; Schiek, Richard; Sholander, Peter E.; Thornquist, Heidi K.; Verley, Jason C.

This manual describes the use of the Xyce Parallel Electronic Simulator. Xyce has been designed as a SPICE-compatible, high-performance analog circuit simulator, and has been written to support the simulation needs of the Sandia National Laboratories electrical designers. This development has focused on improving capability over the current state-of-the-art in the following areas: Capability to solve extremely large circuit problems by supporting large-scale parallel computing platforms (up to thousands of processors). This includes support for most popular parallel and serial computers. A differential-algebraic-equation (DAE) formulation, which better isolates the device model package from solver algorithms. This allows one to develop new types of analysis without requiring the implementation of analysis-specific device models. Device models that are specifically tailored to meet Sandia's needs, including some radiation- aware devices (for Sandia users only). Object-oriented code design and implementation using modern coding practices. Xyce is a parallel code in the most general sense of the phrase -- a message passing parallel implementation -- which allows it to run efficiently a wide range of computing platforms. These include serial, shared-memory and distributed-memory parallel platforms. Attention has been paid to the specific nature of circuit-simulation problems to ensure that optimal parallel efficiency is achieved as the number of processors grows. The information herein is subject to change without notice. Copyright © 2002-2016 Sandia Corporation. All rights reserved.

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TYPE SAND Report YEAR 2016
DOIOSTI

Xyce™ Parallel Electronic Simulator Reference Guide, Version 6.5

Keiter, Eric R.; Aadithya, Karthik V.; Mei, Ting; Russo, Thomas V.; Schiek, Richard; Sholander, Peter E.; Thornquist, Heidi K.; Verley, Jason C.

This document is a reference guide to the Xyce Parallel Electronic Simulator, and is a companion document to the Xyce Users’ Guide. The focus of this document is (to the extent possible) exhaustively list device parameters, solver options, parser options, and other usage details of Xyce. This document is not intended to be a tutorial. Users who are new to circuit simulation are better served by the Xyce Users’ Guide. The information herein is subject to change without notice. Copyright © 2002-2016 Sandia Corporation. All rights reserved.

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TYPE SAND Report YEAR 2016
DOIOSTI

The Password Problem

Walkup, Elizabeth

Passwords are an ubiquitous, established part of the Internet today, but they are also a huge security headache. Single sign-on, OAuth, and password managers are some of the solutions to this problem. OAuth is a new, popular method that allows people to use large, common authentication providers for many web applications. However, it comes at the expense of some privacy: OAuth makes users easy to track across websites, applications, and devices. Password managers put the power in the hands of the users, but this vulnerability survey reveals that you have to be extremely careful which program you choose. All in all, password managers are the solution of choice for home users and small organizations, but large companies will probably want to invest in their own SSO solutions.

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TYPE Thesis or Dissertation YEAR 2016
OSTI

Measuring the radiative properties of astrophysical matter using the Z x-ray source

Bailey, James E.; Nagayama, Taisuke; Loisel, Guillaume P.; Rochau, Gregory A.; Blancard, C.; Colgan, J.; Cosse, Ph; Faussurier, G.; Fontes, C.J.; Gilleron, F.; Golovkin, I.; Hansen, Stephanie B.; Iglesias, C.A.; Kilcrease, D.P.; Macfarlane, Joseph J.; Mancini, Roberto C.; Nahar, S.N.; Orban, C.; Pain, J.C.; Pradhan, A.K.; Sherrill, M.; Wilson, B.G.

Abstract not provided.

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TYPE Conference Poster YEAR 2016
OSTI

Procedure to Determine Coefficients for the Sandia Array Performance Model (SAPM)

King, Bruce H.; Hansen, Clifford; Riley, Daniel; Robinson, Charles D.; Pratt, Larry

The Sandia Array Performance Model (SAPM), a semi-empirical model for predicting PV system power, has been in use for more than a decade. While several studies have presented comparisons of measurements and analysis results among laboratories, detailed procedures for determining model coefficients have not yet been published. Independent test laboratories must develop in-house procedures to determine SAPM coefficients, which contributes to uncertainty in the resulting models. Here we present a standard procedure for calibrating the SAPM using outdoor electrical and meteorological measurements. Analysis procedures are illustrated with data measured outdoors for a 36-cell silicon photovoltaic module.

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TYPE SAND Report YEAR 2016
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DIAGNOSING MAGNETIZED LINER INERTIAL FUSION EXPERIMENTS USING NEUTRON DIAGNOSTICS ON THE Z ACCELERATOR

Hahn, Kelly; Chandler, Gordon A.; Ruiz, Carlos L.; Cooper, Gary; Gomez, Matthew R.; Slutz, Stephen A.; Sefkow, Adam B.; Sinars, Daniel; Hansen, Stephanie B.; Knapp, P.F.; Schmit, Paul; Harding, Eric; Jennings, Christopher A.; Awe, Thomas J.; Geissel, Matthias; Rovang, Dean C.; Torres, Jose; Bur, James A.; Cuneo, Michael E.; Glebov, V.Y.; Harvey-Thompson, Adam J.; Hess, Mark H.; Johns, Owen; Jones, Brent M.; Lamppa, Derek C.; Lash, Joel S.; Martin, Matthew R.; Mcbride, Ryan; Peterson, K.J.; Porter, John L.; Reneker, Joseph; Robertson, G.K.; Rochau, Gregory A.; Savage, Mark E.; Smith, Ian C.; Styron, Jedediah D.; Vesey, Roger A.

Abstract not provided.

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TYPE Conference Poster YEAR 2016
OSTI

Workshop on Incomplete Network Data Held at Sandia National Labs – Livermore

Soundarajan, Sucheta; Wendt, Jeremy D.

While network analysis is applied in a broad variety of scientific fields (including physics, computer science, biology, and the social sciences), how networks are constructed and the resulting bias and incompleteness have drawn more limited attention. For example, in biology, gene networks are typically developed via experiment -- many actual interactions are likely yet to be discovered. In addition to this incompleteness, the data-collection processes can introduce significant bias into the observed network datasets. For instance, if you observe part of the World Wide Web network through a classic random walk, then high degree nodes are more likely to be found than if you had selected nodes at random. Unfortunately, such incomplete and biasing data collection methods must be often used.

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TYPE Other Report YEAR 2016
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DARMA 0.3.0-alpha Specification

Wilke, Jeremiah; Hollman, David S.; Slattengren, Nicole; Lifflander, Jonathan; Kolla, Hemanth; Rizzi, Francesco; Teranishi, Keita; Bennett, Janine C.

In this document, we provide the specifications for DARMA (Distributed Asynchronous Resilient Models and Applications), a co-design research vehicle for asynchronous many-task (AMT) programming models that serves to: 1) insulate applications from runtime system and hardware idiosyncrasies, 2) improve AMT runtime programmability by co-designing an application programmer interface (API) directly with application developers, 3) synthesize application co-design activities into meaningful requirements for runtime systems, and 4) facilitate AMT design space characterization and definition, accelerating the development of AMT best practices.

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TYPE SAND Report YEAR 2016
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Evidence of a Shockley-Read-Hall Defect State Independent of Band-Edge Energy in InAs/In(As,Sb) Type-II Superlattices

Physical Review Applied

Aytac, Y.; Olson, B.V.; Kim, Jin K.; Shaner, Eric A.; Hawkins, Samuel D.; Klem, John F.; Flatte, M.E.; Boggess, T.F.

A set of seven InAs/InAsSb type-II superlattices (T2SLs) were designed to have speci c bandgap energies between 290 meV (4.3 m) and 135 meV (9.2 m) in order to study the e ects of the T2SL bandgap energy on the minority carrier lifetime. A temperature dependent optical pump-probe technique is used to measure the carrier lifetimes, and the e ect of a mid-gap defect level on the carrier recombination dynamics is reported. The Shockley-Read-Hall (SRH) defect state is found to be at energy of approximately -250 12 meV relative to the valence band edge of bulk GaSb for the entire set of T2SL structures, even though the T2SL valence band edge shifts by 155 meV on the same scale. These results indicate that the SRH defect state in InAs/InAsSb T2SLs is singular and is nearly independent of the exact position of the T2SL bandgap or band edge energies. They also suggest the possibility of engineering the T2SL structure such that the SRH state is removed completely from the bandgap, a result that should signi cantly increase the minority carrier lifetime.

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TYPE Journal Article YEAR 2016
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Graphene–Metamaterial Photodetectors for Integrated Infrared Sensing

ACS Photonics

Luxmoore, Isaac J.; Liu, Qiang; Li, Penglei; Faist, Jerome; Nash, Geoffrey R.

We study metamaterial-enhanced graphene photodetectors operating in the mid-IR to THz. The detector element consists of a graphene ribbon embedded within a dual-metal split ring resonator, which acts like a cavity to enhance the absorption of electromagnetic radiation by the graphene ribbon, while the asymmetric metal contacts enable photothermoelectric detection. The detectors we designed for the mid-IR demonstrate peak responsivity (referenced to total power) of ~120 mV/W at 1500 cm-1 and are employed in the spectroscopic evaluation of vibrational resonances, thus demonstrating a key step toward a platform for integrated surface-enhanced sensing.

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TYPE Journal Article YEAR 2016
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Silicon Damage Response Function Derivation and Verification: Assessment of Impact on ASTM Standard E722

Depriest, Kendall R.

Unsuccessful attempts by members of the radiation effects community to independently derive the Norgett-Robinson-Torrens (NRT) damage energy factors for silicon in ASTM standard E722-14 led to an investigation of the software coding and data that produced those damage energy factors. The ad hoc collaboration to discover the reason for lack of agreement revealed a coding error and resulted in a report documenting the methodology to produce the response function for the standard. The recommended changes in the NRT damage energy factors for silicon are shown to have significant impact for a narrow energy region of the 1-MeV(Si) equivalent fluence response function. However, when evaluating integral metrics over all neutrons energies in various spectra important to the SNL electronics testing community, the change in the response results in a small decrease in the total 1- MeV(Si) equivalent fluence of ~0.6% compared to the E722-14 response. Response functions based on the newly recommended NRT damage energy factors have been produced and are available for users of both the NuGET and MCNP codes.

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TYPE SAND Report YEAR 2016
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IDC Re-Engineering Phase 2 Iteration E2 Use Case Realizations

Harris, James M.; Burns, John F.; Hamlet, Benjamin R.; Lober, Randall R.; Vickers, James W.

This architecturally significant use case describes how the System acquires meteorological data to build atmospheric models used in automatic and interactive processing of infrasound data. The System requests the latest available high-resolution global meteorological data from external data centers and puts it into the correct formats for generation of infrasound propagation models. The system moves the meteorological data from Data Acquisition Partition to the Data Processing Partition and stores the meteorological data. The System builds a new atmospheric model based on the meteorological data. This use case is architecturally significant because it describes acquiring meteorological data from various sources and creating dynamic atmospheric transmission model to support the prediction of infrasonic signal detection

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TYPE Other Report YEAR 2016
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Residual Stress Developed During the Cure of Thermosetting Polymers: Optimizing Cure Schedule to Minimize Stress

Kropka, Jamie M.; Stavig, Mark E.; Jaramillo, Rex K.

When thermosetting polymers are used to bond or encapsulate electrical, mechanical or optical assemblies, residual stress, which often affects the performance and/or reliability of these devices, develops within the structure. The Thin-Disk-on-Cylinder structural response test is demonstrated as a powerful tool to design epoxy encapsulant cure schedules to reduce residual stress, even when all the details of the material evolution during cure are not explicitly known. The test's ability to (1) distinguish between cohesive and adhesive failure modes and (2) demonstrate methodologies to eliminate failure and reduce residual stress, make choices of cure schedules that optimize stress in the encapsulant unambiguous. For the 828/DEA/GMB material in the Thin-Disk-on-Cylinder geometry, the stress associated with cure is significant and outweighs that associated with cool down from the final cure temperature to room temperature (for measured lid strain, IεcureI > IεthermalI). The difference between the final cure temperature and the temperature at which the material gels, Tf-Tgel, was demonstrated to be a primary factor in determining the residual stress associated with cure. Increasing Tf-Tgel leads to a reduction in cure stress that is described as being associated with balancing some of the 828/DEA/GMB cure shrinkage with thermal expansion. The ability to tune residual stress associated with cure by controlling Tf-Tgel would be anticipated to translate to other thermosetting encapsulation materials, but the times and temperatures appropriate for a given material may vary widely.

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TYPE SAND Report YEAR 2016
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Results 43201–43400 of 100,993
Results 43201–43400 of 100,993
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