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Displaying 351 - 375 of 489

Successive Frequency Domain Minimization for Time Delay Estimation

November 12, 2013
Author(s)
Ismet Sahin, Marwan A. Simaan, Anthony J. Kearsley
Estimating time delays for signal alignment is important for many applications. This paper extends a successful frequency domain cost function minimization algorithm capable of estimating time delays to within a fraction of sampling periods. Since a narrow

Combining Genetic Algorithms & Simulation to Search for Failure Scenarios in System Models

October 28, 2013
Author(s)
Kevin L. Mills, Christopher E. Dabrowski, James J. Filliben, Sanford P. Ressler
Large infrastructures, such as clouds, can exhibit substantial outages, sometimes due to failure scenarios that were not considered during system design. We define a method that uses a genetic algorithm (GA) to search system simulations for parameter

Shape Calculus for Shape Energies in Image Processing

July 22, 2013
Author(s)
Gunay Dogan, Ricardo H. Nochetto
Many image processing problems are naturally expressed as energy minimization or shape optimization problems, in which the free variable is a shape, such as a curve in 2d or a surface in 3d. Examples are image segmentation, multiview stereo reconstruction

Separation of variables in an asymmetric cyclidic coordinate system

June 27, 2013
Author(s)
Howard S. Cohl, Hans Volkmer
A global analysis is presented of solutions for Laplace's equation on three-dimensional Euclidean space in one of the most general orthogonal asymmetric confocal cyclidic coordinate system which admits solutions through separation of variables. We refer to

Quantifying Network Topology Robustness Under Budget Constraints

June 24, 2013
Author(s)
Assane Gueye, Aron Lazska
To design robust network topologies that resist strategic attacks, one must first be able to quantify robustness. In a recent line of research, the theory of network blocking games has been used to derive robustness metrics for topologies. A network

SHREC13 Track: Large Scale Sketch-Based 3D Shape Retrieval

June 6, 2013
Author(s)
Afzal A. Godil, Bo Li , Yijuan Lu, Tobias Schreck
Sketch-based 3D shape retrieval has become an important research topic in content-based 3D object retrieval. The aim of this track is to measure and compare the performance of sketch-based 3D shape retrieval methods based on a large scale hand-drawn sketch

Continuum-based free vibration of circular trigonal and isotropic plates

May 28, 2013
Author(s)
Ward L. Johnson, Paul R. Heyliger
The free vibration behavior of completely unrestrained elastic circular plates with trig- onal and isotropic material symmetry is studied using approximate solutions to the three- dimensional theory of linear elasticity. Of primary interest are 1) the

Limits in Modeling Power Grid Topology

April 29, 2013
Author(s)
Brian D. Cloteaux
Because of their importance to infrastructure, a number of studies have examined the structural properties of power grids and have proposed random topological models of them. We examine the ability to create generalized models of power grid structure by

On a generalization of the generating function for Gegenbauer polynomials

January 28, 2013
Author(s)
Howard S. Cohl
We derive a Gegenbauer polynomial expansion for complex powers of the distance between two points in $d$-dimensional Euclidean space. The argument of the Gegenbauer polynomial in the expansion is given by the cosine of the separation angle between the two

Bubble motion and size variation during thermal migration with phase change

January 1, 2013
Author(s)
Asha K. Nurse, Geoffrey B. McFadden, Sam R. Coriell
An analysis of the motion of a spherical bubble in a two-phase, single component system with a vertical linear temperature gradient is presented. The model for the migration of an immiscible bubble under the effects of buoyancy and thermocapillarity

Threshold Digraphs

December 5, 2012
Author(s)
Brian D. Cloteaux, Michael D. LaMar, Elizabeth R. Moseman, James Shook
A digraph whose degree sequences have a unique vertex labeled realization is called threshold. In this paper we present several characterizations of threshold digraphs and show them to be equivalent. One of the characterizations is new, and allows for a

Fast Sequential Importance Sampling to Estimate the Graph Reliability Polynomial

November 8, 2012
Author(s)
David G. Harris, Francis Sullivan, Isabel M. Beichl
The reliability polynomial of a graph measures the number of its connected subgraphs of various sizes. Algortihms based on sequential importance sampling (SIS) have been proposed to estimate a graph's reliahbility polynomial. We develop an improved SIS

SysML extension for dynamical system simulation tools

October 26, 2012
Author(s)
Ion Matei, Conrad E. Bock
Computer-interpretable representations of system structure and behavior are at the center of designing today’s complex systems. Engineers create and review such representations using graphical modeling languages that support specification, analysis, design

Definite integrals using orthogonality and integral transforms

October 19, 2012
Author(s)
Howard S. Cohl, Hans Volkmer
We obtain definite integrals for products of associated Legendre functions with Bessel functions, associated Legendre functions, and Chebyshev polynomials of the first kind using orthogonality and integral transforms.
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