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Analysis to determine the maximum dimensions of flexible apertures in sensored security netting products

Murton, Mark

Although technological advances provide new capabilities to increase the robustness of security systems, they also potentially introduce new vulnerabilities. New capability sometimes requires new performance requirements. This paper outlines an approach to establishing a key performance requirement for an emerging intrusion detection sensor: the sensored net. Throughout the security industry, the commonly adopted standard for maximum opening size through barriers is a requirement based on square inchestypically 96 square inches. Unlike standard rigid opening, the dimensions of a flexible aperture are not fixed, but variable and conformable. It is demonstrably simple for a human intruder to move through a 96-square-inch opening that is conformable to the human body. The longstanding 96-square-inch requirement itself, though firmly embedded in policy and best practice, lacks a documented empirical basis. This analysis concluded that the traditional 96-square-inch standard for openings is insufficient for flexible openings that are conformable to the human body. Instead, a circumference standard is recommended for these newer types of sensored barriers. The recommended maximum circumference for a flexible opening should be no more than 26 inches, as measured on the inside of the netting material.

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TYPE SAND Report YEAR 2013
DOIOSTI

Efficient and robust gradient enhanced Kriging emulators

Dalbey, Keith

%E2%80%9CNaive%E2%80%9D or straight-forward Kriging implementations can often perform poorly in practice. The relevant features of the robustly accurate and efficient Kriging and Gradient Enhanced Kriging (GEK) implementations in the DAKOTA software package are detailed herein. The principal contribution is a novel, effective, and efficient approach to handle ill-conditioning of GEK's %E2%80%9Ccorrelation%E2%80%9D matrix, RN%CC%83, based on a pivoted Cholesky factorization of Kriging's (not GEK's) correlation matrix, R, which is a small sub-matrix within GEK's RN%CC%83 matrix. The approach discards sample points/equations that contribute the least %E2%80%9Cnew%E2%80%9D information to RN%CC%83. Since these points contain the least new information, they are the ones which when discarded are both the easiest to predict and provide maximum improvement of RN%CC%83's conditioning. Prior to this work, handling ill-conditioned correlation matrices was a major, perhaps the principal, unsolved challenge necessary for robust and efficient GEK emulators. Numerical results demonstrate that GEK predictions can be significantly more accurate when GEK is allowed to discard points by the presented method. Numerical results also indicate that GEK can be used to break the curse of dimensionality by exploiting inexpensive derivatives (such as those provided by automatic differentiation or adjoint techniques), smoothness in the response being modeled, and adaptive sampling. Development of a suitable adaptive sampling algorithm was beyond the scope of this work; instead adaptive sampling was approximated by omitting the cost of samples discarded by the presented pivoted Cholesky approach.

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TYPE SAND Report YEAR 2013
DOIOSTI

Construction of reduced order models for the non-linear Navier-Stokes equations using the proper orthogonal fecomposition (POD)/Galerkin method

Fike, Jeffrey

The construction of stable reduced order models using Galerkin projection for the Euler or Navier-Stokes equations requires a suitable choice for the inner product. The standard L2 inner product is expected to produce unstable ROMs. For the non-linear Navier-Stokes equations this means the use of an energy inner product. In this report, Galerkin projection for the non-linear Navier-Stokes equations using the L2 inner product is implemented as a first step toward constructing stable ROMs for this set of physics.

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TYPE SAND Report YEAR 2013
DOIOSTI

Protocol for uniformly measuring and expressing the performance of energy storage systems

Ferreira, Summer R.; Rosewater, David; Schoenwald, David A.

The U.S. Department of Energys Energy Storage Systems (ESS) Program, through the support of Pacific Northwest National Laboratory (PNNL) and Sandia National Laboratories (SNL), facilitated the development of the protocol provided in this report. The focus of the protocol is to provide a uniform way of measuring, quantifying, and reporting the performance of ESSs in various applications; something that does not exist today and, as such, is hampering the consideration and use of this technology in the market. The availability of an application-specific protocol for use in measuring and expressing performance-related metrics of ESSs will allow technology developers, power-grid operators and other end-users to evaluate the performance of energy storage technologies on a uniform and comparable basis. This will help differentiate technologies and products for specific application(s) and provide transparency in how performance is measured. It also will assist utilities and other consumers of ESSs to make more informed decisions as they consider the potential application and use of ESSs, as well as form the basis for documentation that might be required to justify utility investment in such technologies.

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TYPE SAND Report YEAR 2013
DOIOSTI

Application note :

Russo, Thomas V.

The development of the XyceTM Parallel Electronic Simulator has focused entirely on the creation of a fast, scalable simulation tool, and has not included any schematic capture or data visualization tools. This application note will describe how to use the open source schematic capture tool gschem and its associated netlist creation tool gnetlist to create basic circuit designs for Xyce, and how to access advanced features of Xyce that are not directly supported by either gschem or gnetlist.

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TYPE SAND Report YEAR 2013
DOIOSTI

A 3D Orthotropic Elastic Continuum Damage Material Model

English, Shawn A.; Brown, Arthur

A three dimensional orthotropic elastic constitutive model with continuum damage is implemented for polymer matrix composite lamina. Damage evolves based on a quadratic homogeneous function of thermodynamic forces in the orthotropic planes. A small strain formulation is used to assess damage. In order to account for large deformations, a Kirchhoff material formulation is implemented and coded for numerical simulation in Sandia’s Sierra Finite Element code suite. The theoretical formulation is described in detail. An example of material parameter determination is given and an example is presented.

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TYPE SAND Report YEAR 2013
DOIOSTI

Building guide : how to build Xyce from source code

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

While Xyce uses the Autoconf and Automake system to configure builds, it is often necessary to perform more than the customary %E2%80%9C./configure%E2%80%9D builds many open source users have come to expect. This document describes the steps needed to get Xyce built on a number of common platforms.

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TYPE SAND Report YEAR 2013
DOIOSTI

Xyce parallel electronic simulator users guide, version 6.0

Russo, Thomas V.; Mei, Ting; Keiter, Eric R.; Schiek, Richard; Thornquist, Heidi K.; Verley, Jason C.; Coffey, Todd S.; Pawlowski, Roger; Warrender, Christina E.

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 Sandias needs, including some radiationaware 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.

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TYPE SAND Report YEAR 2013
DOIOSTI

Xyce parallel electronic simulator reference guide, version 6.0

Keiter, Eric R.; Mei, Ting; Russo, Thomas V.; Pawlowski, Roger; Schiek, Richard; Coffey, Todd S.; Thornquist, Heidi K.; Verley, Jason C.; Warrender, Christina E.

This document is a reference guide to the Xyce Parallel Electronic Simulator, and is a companion document to the Xyce Users Guide [1] . 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 [1] .

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TYPE SAND Report YEAR 2013
DOIOSTI

Sandia Micro-fabricated Ion Traps for the MUSIQC architecture

Maunz, Peter L.W.; Heller, Edwin J.; Hollowell, Andrew E.; Kemme, Shanalyn A.; Loviza, Becky G.; Mizrahi, Jonathan A.; Ortega, Anathea C.; Scrymgeour, David; Sterk, Jonathan D.; Tigges, Chris P.; Dagel, Amber; Clark, Craig R.; Stick, Daniel L.; Blain, Matthew G.; Clark, Susan M.; Resnick, Paul; Arrington, Christian L.; Benito, Francisco M.; Boye, Robert; Ellis, A.R.; Haltli, Raymond A.

Abstract not provided.

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TYPE Conference YEAR 2013
OSTI

General purpose steam table library :

Carpenter, John H.; Belcourt, Kenneth

Completion of the CASL L3 milestone THM.CFD.P7.04 provides a general purpose tabular interpolation library for material properties to support, in particular, standardized models for steam properties. The software consists of three parts, implementations of analytic steam models, a code to generate tables from those models, and an interpolation package to interface the tables to CFD codes such as Hydra-TH. Verification of the standard model is maintained through the entire train of routines. The performance of interpolation package exceeds that of freely available analytic implementation of the steam properties by over an order of magnitude.

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TYPE SAND Report YEAR 2013
DOIOSTI
Results 56801–57000 of 99,299
Results 56801–57000 of 99,299