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Uncertainty of FEM Solutions Using a Nonlinear Least Squares Fit Method and a Design of Experiments Approach

October 7, 2015

Author(s)

Jeffrey T. Fong, Nathanael A. Heckert, James J. Filliben, Pedro V. Marcal, Robert Rainsberger

Uncertainty in COMSOL finite element simulations due to (a) mesh-induced truncation errors, and (b) model parameter uncertainties, is estimated using a nonlinear least squares logistic distribution fit method, and a design-of-experiments approach

Equilibrium and stability of axisymmetric drops on a conical substrate under gravity

October 4, 2015

Author(s)

Asha K. Nurse, Sean A. Colbert-Kelly, Sam R. Coriell, Geoffrey B. McFadden

Motivated by recent investigations of toroidal tissue clusters that are observed to climb conical obstacles after self-assembly, we study a related problem of the determination of the equilibrium and stability of axisymmetric drops on a conical substrate

A Self Learning Algorithm for Temperature Prediction in a Single Family Residence

September 29, 2015

Author(s)

Farhad Omar, Steven Bushby

In order to develop effective control optimization strategies to manage residential electricity consumption in a smart grid environment, predictive algorithms are needed that are simple to implement, minimize custom configuration, and provide enough

Some dual definite integrals for Bessel functions

September 24, 2015

Author(s)

Howard S. Cohl, Rebekah M. Palmer, Sean Nair

Based on known definite integrals of Bessel functions of the first kind, we obtain exact solutions to unknown definite integrals using the method of integral transforms from Hankel's transform.

Percolation phase diagrams for multi-phase models built on the overlapping sphere model

September 16, 2015

Author(s)

Edward J. Garboczi

The overlapping sphere (OS) model gives a two-phase microstructure (matrix plus inclusions) that is useful for testing out composite material ideas and other applications, as well as serving as a paradigm of continuum percolation and phase transitions

Simple FMM libraries for electrostatics, slow viscous flow, and frequency-domain wave propagation

July 30, 2015

Author(s)

Zydrunas Gimbutas, Leslie Greengard

We have implemented easy to use FMM libraries for the Laplace, Helmholtz and Stokes equations in two and three dimensions. The codes are based on a new method for applying translation operators and provide reasonable performance on either single core

Kinetics of the Reactions of H and CH3 with n-Alkanes: Experiments with n-Butane and a Reevaluation Based on a Combustion Model Reaction Network Analysis

July 16, 2015

Author(s)

Jeffrey A. Manion, David A. Sheen, Iftikhar A. Awan

Presented is a combined experimental and modeling study of the kinetics of the reactions of H and CH3 with n-butane, a representative aliphatic fuel. Abstraction of H from n-alkane fuels creates alkyl radicals that rapidly decompose at high temperatures to

Simple and efficient representations for the fundamental solutions of Stokes flow in a half-space

July 2, 2015

Author(s)

Zydrunas Gimbutas, Leslie Greengard, Shravan Veerapaneni

We derive new formulas for the fundamental solutions of slow, viscous flow, governed by the Stokes equations, in a half-space. They are simpler than the classical representations obtained by Blake and collaborators, and can be efficiently implemented using

Sharp interface model of creep deformation in crystalline solids

June 30, 2015

Author(s)

Yuri Mishin, Geoffrey B. McFadden, Robert F. Sekerka, William J. Boettinger

We present a rigorous irreversible thermodynamics treatment of creep deformation of solid mate- rials with interfaces described as geometric surfaces capable of vacancy generation and absorption and moving under the influence of local thermodynamic forces

Methodology and Calculator for High Precision Regression Fits of Pyranometer Angular Responsivities and the Associated Uncertainties

June 23, 2015

Author(s)

Matthew T. Boyd

An easy to implement method for accurately utilizing pyranometer incidence angle dependent calibration factors, or responsivities (uV/W/m2), along with the associated uncertainties has been developed. This method uses algorithms for creating single

The effect of systematic errors on the hybridization of optical critical dimension measurements

June 21, 2015

Author(s)

Mark Alexander Henn, Richard M. Silver, Nien F. Zhang, Hui Zhou, Bryan M. Barnes

In hybrid metrology two or more measurements of the same measurand are combined to provide a more reliable result that ideally incorporates the individual strengths of each of the measurement methods. While these multiple measurements may come from

The Decoupled Potential Integral Equation for Time-Harmonic Electromagnetic Scattering

May 28, 2015

Author(s)

Felipe Vico, Leslie Greengard, Miguel Ferrando, Zydrunas Gimbutas

We present a new formulation for the problem of electromagnetic scattering from perfect electric conductors. While our representation for the electric and magnetic fields is based on the standard vector and scalar potentials A, φ in the Lorenz gauge, we

UWB Signal Processing: Projection, B-Splines, and Modified Gegenbauer Bases

May 25, 2015

Author(s)

Howard S. Cohl, Stephen D. Casey

Ultra-wide band (UWB) systems require either rapidly changing or very high sampling rates. Conventional analog-to-digital devices have limited dynamic range. We investigate UWB signal processing via a basis projection method and a basis system designed for

Area Coverage in a Fixed-Obstacle Environment using Mobile Sensor Networks

May 17, 2015

Author(s)

Kamran Sayrafian, Hamid Mahboubi, Amir Aghdam

In this chapter, efficient deployment strategies for mobile sensor networks are proposed to improve the coverage area in target fields containing obstacles. The developed algorithms iteratively calcu- late and update the position of the sensors in order to

Erratum to ``Bessel Functions'' (2014) by K.~B.~M.~Nambudiripad

May 15, 2015

Author(s)

Howard S. Cohl

The following errors and misprints have been detected in the monograph of Nambudiripad (2014) "Bessel Functions", Alpha Science International Ltd., Oxford, U.K.

Tokamak Plasma High Field Side Response to an n = 3 Magnetic Perturbation: A Comparison of 3D Equilibrium Solutions from Seven Different Codes

May 15, 2015

Author(s)

Allan Reiman, Antoine Cerfon, Geoffrey B. McFadden

In comparing equilibrium solutions for a DIII-D shot that is amenable to analysis by both stellarator and tokamak 3D equilibrium codes, a significant disagreement has been seen between solutions of the VMEC stellarator equilibrium code and solutions of

Design and modeling of an ultra-compact 2x2 nanomechanical plasmonic switch

May 4, 2015

Author(s)

Vladimir A. Aksyuk

A 2x2 Mach-Zehnder optical switch design with a footprint of 0.5 um x 2.5 um using nanomechanical gap plasmon phase modulators [1] is presented. The extremely small footprint and modest optical loss are enabled by the strong phase modulation of gap

A fast multipole method for the evaluation of elastostatic fields in a half-space with zero normal stress

April 30, 2015

Author(s)

Zydrunas Gimbutas, Leslie Greengard

In this paper, we present a fast multipole method (FMM) for the half-space Green's function in a homogeneous elastic half-space subject to zero normal stress, for which an explicit solution was given by Mindlin (1936). The image structure of this Green's

Fast Minimization of Region-based Active Contours using the Shape Hessian of the Energy

April 28, 2015

Author(s)

Gunay Dogan

We propose a novel shape optimization algorithm for region-based active contour models. Region-based active contours are preferred for many segmentation problems, because they incorporate more global information by aggregating cues or statistics over the

On the Stability of Rotating Drops

April 20, 2015

Author(s)

Asha K. Nurse, Sam R. Coriell, Geoffrey B. McFadden

We consider the equilibrium and stability of rotating axisymmetric fluid drops by appealing to a variational principle that characterizes the equilibria as stationary states of a functional containing surface energy and rotational energy contributions

Assessing Effects of Asymmetries, Dynamics, and Failures on a Cloud Simulator

March 29, 2015

Author(s)

Kevin L. Mills, James J. Filliben, Christopher E. Dabrowski

We characterize the effects of asymmetries, dynamics, and failures when introduced into a cloud computing simulator, which had previously been characterized under static, homogeneous configurations with various patterns of demand and supply. We aim to

A comparison of 3D shape retrieval methods based on a large-scale benchmark supporting multimodal queries

March 27, 2015

Author(s)

Afzal A. Godil

Large-scale 3D shape retrieval has become an important research direction in content-based 3D shape retrieval. To promote this research area, two Shape Retrieval Contest (SHREC) tracks on large scale comprehensive and sketch-based 3D model retrieval have

Multiscale Greens functions for modeling of nanomaterials: Bridging length and time scales

March 17, 2015

Author(s)

Vinod K. Tewary

Green's function gives the response of a system to a probe and is a powerful technique for solving a variety of problems in science and engineering. We describes a multiscale Green's function method for modeling nanomaterials at different length and time

Grain-scale thermoelastic stresses and spatiotemporal temperature gradients on airless bodies, implications for rock breakdown.

February 25, 2015

Author(s)

Stephen A. Langer

Thermomechanical processes such as fatigue and shock have been suggested to cause and contribute to rock breakdown on Earth, and on other planetary bodies, particularly airless bodies in the inner solar system. In this study, we modeled grain-scale

Computing the Time Evolution of the Apparent Viscoelastic/Viscoplastic Poisson's Ratio of Hydrating Cement Paste

February 15, 2015

Author(s)

Li xiodan, Zachary Grasley, Jeffrey W. Bullard, Edward Garboczi

A computational model has been developed that combines finite element methods with microstructure development simulations to quantitatively predict the viscoelastic/viscoplastic relaxation of cement paste due to intrinsic calcium silicate hydrate