Results 61 to 70 of about 5,632,119 (202)

Uncertainty in structure dynamics resulting from matrix ill-conditioning

Archives of Acoustics, 2014
In the paper there are discussed certain issues concerning ill-posed problems that frequently appear in inverse problems, modal analysis, acoustics and other methods making use of matrix algebra.
J. IWANIEC
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A bootstrap multi-user detector for CDMA based on Tikhonov regularization [PDF]

, 2003
A novel multi-user detection (MUD) technique for CDMA systems is introduced. The new method is well suited for cases in which the code cross correlation matrix is ill-conditioned.
Nix, AR, Fletcher, PN, Piechocki, RJ, Kasparis, C   +3 more
core  

Nonautonomous ill-posed evolution problems with strongly elliptic differential operators

Electronic Journal of Differential Equations, 2013
In this article, we consider the nonautonomous evolution problem $du/dt=a(t)Au(t), 0leq sleq t< T$ with initial condition $u(s)=chi$ where -A generates a holomorphic semigroup of angle $heta in (0,pi/2]$ on a Banach space X and $ain C([0,T]:mathbb{R}^+
Matthew A. Fury
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Physics‐Informed Estimation of Tidal and Subtidal Flow Fields From ADCP Repeat Transect Data

Water Resources Research
Acoustic Doppler current profilers (ADCPs) are a global standard in observing flow fields in rivers, estuaries and the coastal ocean. To date, it remains a labor intensive challenge to isolate mean flow fields governed by river discharge, tides and ...
H. Jongbloed, B. Vermeulen, A. J. F. Hoitink   +2 more
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A simplified homotopy perturbation method for solving nonlinear ill-posed operator equations in Hilbert spaces

Journal of Numerical Analysis and Approximation Theory
One popular regularization technique for handling both linear and nonlinear ill-posed problems is homotopy perturbation. In order to solve nonlinear ill-posed problems, we investigate an iteratively-regularized simplified version of the Homotopy ...
Sharad Kumar Dixit
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A Generalized Tikhonov Regularization Using Two Parameters Applied to Linear Inverse Ill-Posed Problems

Revista de Ciencias, 2007
A Generalized Tikhonov Regularization Using Two Parameters Applied to Linear Inverse Ill-Posed ...
Doris Hinestroza, Luisa Fernanda Vargas
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Regularization of Linear Ill-posed Problems in Two Steps: Combination of Data Smoothing and Reconstruction Methods

, 2006
This thesis is a contribution to the field of ill-posed inverse problems . During the last ten years a new development in this field has taken place: Besides operator-adapted methods for the solution of inverse problems also methods adjusted to ...
Klann, Esther
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Iterative Methods for Data Assimilation for Burgers's Equation

, 2006
In this paper we consider one-dimensional flow governed by Burgers' equation. We analyze two iterative methods for data assimilation problem for this equation. One of them so called adjoint optimization method, is based on minimization in L 2-norm.
Weinerfelt, Per,, Lundvall, Johan,, Kozlov, Vladimir,   +2 more
core   +1 more source

On the ill-posed problem for the Poisson equation

Қарағанды университетінің хабаршысы. Математика сериясы, 2018
A boundary value problem in a two - dimensional rectangular region for the Poisson equation is studied in the paper. The original ill - posed boundary value problem is transformed to the optimal control problem.
M.T. Jenaliyev, M.M. Amangaliyeva, K.B. Imanberdiyev   +2 more
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DETERMINATION OF SELECTED PARAMETERS IN A 1D OPEN CHANNEL FLOW MODEL

TASK Quarterly, 2007
Determination of the model’s parameters is an important stage of mathematical models’ application. In the case of a free-surface 1D unsteady flow model defined by the de Saint-Venant equations, one of the groups of parameters to be estimated is the set ...
KATARZYNA WEINEROWSKA-BORDS
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