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The Influence of Realism on Congestion in Network Simulations

January 8, 2016

Author(s)

Kevin L. Mills, Christopher E. Dabrowski

Many researchers have used simulation to investigate the spread of congestion in networks. These researchers often find that congestion can be modeled as a percolation process, spreading slowly under increasing load until a critical point. After the

Uncertainty Quantification of Stresses in a Cracked Pipe Elbow Weldment Using a Logistic Function Fit, a Nonlinear Least Squares Algorithm, and a Super-Parametric Method

December 30, 2015

Author(s)

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

In a 3-part series of papers, of which this paper is Part II, we investigate the applicability of the fully quadratic hexa-27 element (see Part I) to four problems of interest to the pressure vessels and piping community: (1) The solid-element-based

Algorithms for Identification of Nearly-Coincident Events in Calorimetric Sensors

December 29, 2015

Author(s)

Bradley K. Alpert, Elena Ferri, Douglas A. Bennett, Marco Faverzani, Joseph W. Fowler, Andrea Giachero, James P. Hays-Wehle, Angelo Nucciotti, Daniel S. Swetz, Joel N. Ullom

For experiments with high arrival rates, reliable identification of nearly-coincident events can be crucial. For calorimetric measurements to directly measure the neutrino mass such as HOLMES, unidentified pulse pile-ups are expected to comprise a leading

Finite difference micromagnetic solvers with Object Oriented Micromagnetic Framework on graphics processing units

November 23, 2015

Author(s)

Michael J. Donahue, Sidi Fu, Weilong Cui, Matthew Hu, Ruinan Chang, Vitaliy Lomakin

A micromagnetic solver with Finite Difference method on Graphics Processing Unit (GPU) and its integration with the Object Oriented MicroMagnetic Framework (OOMMF) are presented. Two approaches for computing the magnetostatic field accelerated by Fast

Inverse Method for Estimating Shear Stress in Machining

November 3, 2015

Author(s)

Timothy J. Burns, Steven P. Mates, Richard L. Rhorer, Eric P. Whitenton, Debasis Basak

An inverse method is presented for estimating the shear stress in the work material in the region of chip-tool contact along the rake face of the tool during orthogonal machining. The method uses an estimate of the temperature of the work material as it

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 T. 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