Search Results

Advanced search parameters have been applied.
open access

Periodized Wavelets

Description: The properties of periodized Daubechies wavelets on [0,1] are detailed and contrasted against their counterparts which form a basis for L{sup 2}(R). Numerical examples illustrate the analytical estimates for convergence and demonstrate by comparison with Fourier spectral methods the superiority of wavelet projection methods for approximations. The analytical solution to inner products of periodized wavelets and their derivatives, which are known as connection coefficients, is presented, and sev… more
Date: December 1993
Creator: Schlossnagle, George; Restrepo, Juan Mario & Leaf, Gary K.
Partner: UNT Libraries Government Documents Department
open access

Problem Proposed for the American Mathematical Monthly

Description: The problem is to define: P(x) := {Sigma}{sub k = 1}{sup {infinity}} arctan (x - 1/(k + x + 1) {radical}(k + 1) + (k + 2) {radical}(k + x)). (1) (a) Find explicit, finite-expression evaluations of P(n) for all integers n {ge} 0. (b) Show {tau} := lim{sub x {yields} -1{sup +}} P(x) exists, and find an explicit evaluation for {tau}. (c) Are there a more general closed forms for P, say at half-integers? Solution with the abbreviations: r := {radical} (k + 1), s := {radical} (k + x) the argument of… more
Date: November 14, 2008
Creator: Bailey, David H.; Borwein, Jonathan M. & Waldvogel, Jorg
Partner: UNT Libraries Government Documents Department
open access

Dynamics, Thermodynamic formalism and Perturbations of Transcendental Entire Functions of Finite Singular Type

Description: In this dissertation, we study the dynamics, fractal geometry and the topology of the Julia set of functions in the family H which is a set in the class S, the Speiser class of entire transcendental functions which have only finitely many singular values. One can think of a function from H as a generalized expanding function from the cosh family. We shall build a version of thermodynamic formalism for functions in H and we shall show among others, the existence and uniqueness of a conformal mea… more
Date: May 2005
Creator: Coiculescu, Ion
Partner: UNT Libraries
open access

Professional correspondence

Description: This letter discusses interpolation methods; it is prompted by Akima`s note on local methods of univariate interpolation (April 1996 issue of SIGNUM Newsletter). That note compared various univariate methods, concluding that Algorithm 697 is probably the best. Purpose of this letter is provide information about PCHIC comparable to that given in Akima`s note. The 4 methods (Alg. 514, Alg. 697, PCHIC0, PCHIC1) are applied to the 5 analytic functions in Ellis and McLain`s paper (x{sup 3}, x{sup 4}… more
Date: February 6, 1997
Creator: Fritsch, F. N.
Partner: UNT Libraries Government Documents Department
open access

Scattering of color dipoles: from low to high energies

Description: A dipole-dipole scattering amplitude is calculated exactly in the first two orders of perturbation theory. This amplitude is an analytic function of the relative energy and the dipoles' sizes. The cross section of the dipole-dipole scattering approached the high-energy BFKL asymptotics starting from relatively large rapidity {approx}4.
Date: November 1, 2002
Creator: Babansky, Alexander & Balitsky, Ian
Partner: UNT Libraries Government Documents Department
open access

Thermodynamic Model of Afterburning in Explosions

Description: Thermodynamic states encountered during afterburning of explosion products gases in air were analyzed with the Cheetah code. Results are displayed in the form of Le Chatelier diagrams: the locus of states of specific internal energy versus temperature, for six different condensed explosives charges. Accuracy of the results was confirmed by comparing the fuel and products curves with the heats of detonation and combustion, and species composition as measured in bomb calorimeter experiments. Resu… more
Date: April 23, 2003
Creator: Kuhl, A L; Howard, M & Fried, L
Partner: UNT Libraries Government Documents Department
open access

On Quantum Integrable Systems

Description: Many quantum integrable systems are obtained using an accelerator physics technique known as Ermakov (or normalized variables) transformation. This technique was used to create classical nonlinear integrable lattices for accelerators and nonlinear integrable plasma traps. Now, all classical results are carried over to a nonrelativistic quantum case. In this paper we have described an extension of the Ermakov-like transformation to the Schroedinger and Pauli equations. It is shown that these new… more
Date: November 1, 2011
Creator: Danilov, Viatcheslav & Nagaitsev, Sergei
Partner: UNT Libraries Government Documents Department
open access

Periodized wavelets

Description: The properties of periodized Daubechies wavelets on [0,1] are detailed and contrasted against their counterparts which form a basis for L{sup 2}(R). Numerical examples illustrate the analytical estimates for convergence and demonstrate by comparison with Fourier spectral methods the superiority of wavelet projection methods for approximations. The analytical solution to inner products of periodized wavelets and their derivatives, which are known as connection coefficients, is presented, and sev… more
Date: December 1, 1993
Creator: Schlossnagle, G.; Restrepo, J. M. & Leaf, G. K.
Partner: UNT Libraries Government Documents Department
open access

L/sup 2/ approach to R-matrix propagation: followup report. [Close-coupling methods, hybrid approach]

Description: A hybridized R-matrix propagation program was used to solve the four test problems presented by the NRCC workshop on close coupling methods. The hybrid method used both the L/sup 2/ approach reported earlier and the analytic (constant reference potential) method. Observations on the utility of the hybrid approach are presented. 2 references.
Date: January 1, 1979
Creator: Walker, R.B.
Partner: UNT Libraries Government Documents Department
open access

Strong uniqueness of best complex Chebyshev approximation to analytic perturbations of analytic function

Description: By studying the strong uniquess properties of best complex Chebyshev approximations to perturbations of a special class of functions, we show that strong uniqueness is not a generic property when we restrict ourselves to nonoscillatory'' functions. 10 refs.
Date: March 8, 1988
Creator: Tang, Ping Tak Peter.
Partner: UNT Libraries Government Documents Department
open access

Verification of the coupled fluid/solid transfer in a CASL grid-to-rod-fretting simulation : a technical brief on the analysis of convergence behavior and demonstration of software tools for verification.

Description: For a CASL grid-to-rod fretting problem, Sandia's Percept software was used in conjunction with the Sierra Mechanics suite to analyze the convergence behavior of the data transfer from a fluid simulation to a solid mechanics simulation. An analytic function, with properties relatively close to numerically computed fluid approximations, was chosen to represent the pressure solution in the fluid domain. The analytic pressure was interpolated on a sequence of grids on the fluid domain, and transfe… more
Date: December 1, 2011
Creator: Copps, Kevin D.
Partner: UNT Libraries Government Documents Department
open access

Elements of a function analytic approach to probability.

Description: We first provide a detailed motivation for using probability theory as a mathematical context in which to analyze engineering and scientific systems that possess uncertainties. We then present introductory notes on the function analytic approach to probabilistic analysis, emphasizing the connections to various classical deterministic mathematical analysis elements. Lastly, we describe how to use the approach as a means to augment deterministic analysis methods in a particular Hilbert space cont… more
Date: February 1, 2008
Creator: Ghanem, Roger Georges (University of Southern California, Los Angeles, CA) & Red-Horse, John Robert
Partner: UNT Libraries Government Documents Department
open access

Thermodynamic Model of Aluminum Combustion in SDF Explosions

Description: Thermodynamic states encountered during combustion of Aluminum powder in Shock-Dispersed-Fuel (SDF) explosions were analyzed with the Cheetah code. Results are displayed in the Le Chatelier diagram: the locus of states of specific internal energy versus temperature. Accuracy of the results was confirmed by comparing the fuel and products curves with the heats of detonation and combustion, and species composition as measured in bomb calorimeter experiments. Results were fit with analytic functio… more
Date: June 19, 2006
Creator: Kuhl, . L
Partner: UNT Libraries Government Documents Department
open access

The VNIIEF magnetic bubble approach to an x-ray source

Description: Both analytic and cursory numerical investigations indicate that the All-Russian Scientific Institute for Experimental Physics (VNIIEF) approach to x-ray generation has potential advantages. An experimental test of this concept was conducted at VNIIEF in Sarov, Russia, in the spring of 1994. We present only the analytic and numerical investigations, which clearly demonstrate the potential advantages of this approach. 5 figs.
Date: August 1, 1997
Creator: Kirkpatrick, R.C.
Partner: UNT Libraries Government Documents Department
open access

Simulation of Turbulent Combustion Fields of Shock-Dispersed Aluminum Using the AMR Code

Description: We present a Model for simulating experiments of combustion in Shock-Dispersed-Fuel (SDF) explosions. The SDF charge consisted of a 0.5-g spherical PETN booster, surrounded by 1-g of fuel powder (flake Aluminum). Detonation of the booster charge creates a high-temperature, high-pressure source (PETN detonation products gases) that both disperses the fuel and heats it. Combustion ensues when the fuel mixes with air. The gas phase is governed by the gas-dynamic conservation laws, while the partic… more
Date: November 2, 2006
Creator: Kuhl, A L; Bell, J B; Beckner, V E & Khasainov, B
Partner: UNT Libraries Government Documents Department
open access

Higgs-type Lagrangians and vortex-line and soliton solutions

Description: Approximate vortex-line and soliton solutions of the Higgs-type Lagrangian are obtained analytically, and the magnetic field, magnetic energy and its root mean square radius, Higgs energy, and interaction energy between the vector field A/sub ..mu../ and the Higgs scalar phi are calculated. The soliton solution for another case is commented on. (auth)
Date: January 1, 1975
Creator: Hietarinta, J.; Takasugi, E. & Tanaka, K.
Partner: UNT Libraries Government Documents Department
open access

Analytical considerations in the code qualification of piping systems

Description: The paper addresses several analytical topics in the design and qualification of piping systems which have a direct bearing on the prediction of stresses in the pipe and hence on the application of the equations of NB, NC and ND-3600 of the ASME Boiler and Pressure Vessel Code. For each of the analytical topics, the paper summarizes the current code requirements, if any, and the industry practice.
Date: February 1, 1995
Creator: Antaki, G. A.
Partner: UNT Libraries Government Documents Department
open access

Discontinuity formulas for multiparticle amplitudes

Description: It is shown how discontinuity formulas for multiparticle scattering amplitudes are derived from unitarity and analyticity. The assumed analyticity property is the normal analytic structure, which was shown to be equivalent to the space-time macrocausality condition. The discontinuity formulas to be derived are the basis of multi-particle fixed-t dispersion relations.
Date: March 1, 1976
Creator: Stapp, H. P.
Partner: UNT Libraries Government Documents Department
open access

Pulsed rf operation analysis

Description: The need for a very low final amplifier output impedance, always associated with class A operation, requires a very large power waste in the final tube. The recently suggested pulsed rf operation, while saving a large amount of power, increases the inherent final amplifier non linearity. A method is presented for avoiding the large signal non linear analysis and it is shown how each component of the beam induced voltage depends upon all the beam harmonics via some coupling coefficients which ar… more
Date: January 1, 1981
Creator: Puglisi, M. & Cornacchia, M.
Partner: UNT Libraries Government Documents Department
Back to Top of Screen