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Estimating error uncertainties arising in parts produced on machine tools in production machine shops is not a well understood process. The current study details a process of estimating these error uncertainties. A part with significant features was
Bivariate cubic L1 smoothing splines are introduced. The coefficients of a cubic L1 smoothing spline are calculated by minimizing the weighted sum of the L1 norms ofsecond derivatives of the spline and the l1 norm of the residuals of the data-fitting
Nonlinear time delay differential equations are well known to have arisen in models in physiology, biology and population dynamics. They have also arisen in models of metal cutting processes. Machine tool chatter, from a process called regenerative chatter
Rendering is the process of producing a synthetic image using a computer. The best known application is animation and simulation of scenes for the entertainment industry but recognition of its value as a tool for product design in other areas is increasing
In theory, physical crystals can be represented by idealized mathematical lattices. Under appropriate conditions, these representations can be used for a variety of purposes such as identifying, classifying, and understanding the physical properties of
Given a perturbed Hamiltonian system, normalization yields a Lie transformation which converts the main part of the Hamiltonian into an integral of the transformed system. An extension of the normalization method--the relegation algorithm--does the same
This paper documents the construction of a finite element, called the Sibson element. The shape function of this element is formed on rectangular grids by C 1 splines defined on a triangulation of each subrectangle by dividing it into four subtriangles
We describe a systematic approach to the recovery of a function analytic in the upper half plane, ${\bfC:^+$, from measurements over a finite interval on the real axis, $D\subset {\bfR}$. Analytic continuation problems of this type are well-known to ill
Many algorithms that are currently used for the solution of the Helmholtz equation in periodic domains require the evaluation of the Green s function, G(x, x0). The fact that the natural representation of G via the method of images gives rise to a
Cubic L 1 and L 2 interpolating splines based on C 1 smooth piecewise cubic Sibson elements on a tensor-product grid are investigated. Computational tests were carried out for a 102.4 km area of Fort Hood, Texas represented by a 1025 x 1025 set of 100
The BEAK method is an FFT-based direct blind deconvolution technique previously introduced by the author, and applied to a limited but significant class of blurs that can be expressed as convolutions of 2-D symmetric L vy probability density functions
This paper discusses an easy to implement procedure for approximating the long time behavior of iterates of maps. Applications include to finding the roots of a complex polynomial and approximating attractors. The method uses the theory of Markov chains.
K Devine, B Hendrickson, E Boman, M St. John, C Vaughan, William F. Mitchell
The Zoltan Dynamic Load-Balancing Library provides critical capability to a number of parallel applications. Zoltan includes a suite of algorithms for dynamically computing partitions of problems over sets of processors; geometric, tree-based and graph
K Devine, B Hendrickson, E Boman, M St. John, C Vaughan, William F. Mitchell
The Zoltan Dynamic Load-Balancing Library provides critical capability to a number of parallel applications. Zoltan includes a suite of algorithms for dynamically computing partitions of problems over sets of processors; geometric, tree-based and graph
Timothy J. Burns, Matthew A. Davies, Christopher J. Evans
We describe a new approach to modeling chip formation in orthogonal machining. Metal cutting is interpreted as a nonlinear dynamical process with thermomechanical feedback, which is similar in many ways to an open chemical reactor. As the cutting speed is
Fern Y. Hunt, Egon Marx, G W. Meyer, Theodore V. Vorburger, P A. Walker, H B. Westlund
We seek to explore the feasibility of producing computer graphic images to visualize the color and gloss of surfaces using optical and surface topographical data.
NIST (formerly, National Bureau of Standards) has started an ambitious project that aims to produce a successor to Abramowitz and Stegun's {\em Handbook of Mathematical Functions}, published by the National Bureau of Standards in 1964 and reprinted by
Wills (1990, J. Phys., Paris 51, 1061), found a method relating certain decagonal disk packings to decagonal sphere packings with high packing fractions. Applying this technique to the decagonal rectangle-triangle tiling generated by inflation, we obtain a
This paper examines a wide class of ill-posed initial value problems for partial differential equations, and surveys logarithmic convexity results leading to Hoelder-continuous dependence on data for solutions satisfying prescribed bounds. The discussion
This article extends the results of [3] by establishing sufficient conditions for the limit distribution of products of i.i.d. 2 x 2 random stochastic matrices to be continuous singular, when the support of the distribution of the individual random
The general theories of the derivation of inverses of functions from their power series and asymptotic expansions are discussed and compared. The asymptotic theory is applied to obtain asymptotic expansions of the zeros of the Airy functions and their
Multimedia content is designed for many purposes and the services that are associated with them rely heavily on technologies that address representation, processing, and transmission of that content. This paper presents a new model that refines the
We present the theoretical basis for a novel way of studying and representing the long time behavior of finite dimensional maps. It is based on the sample paths of a Markov chain. Applications of the method to the approximation of attractors of maps and to