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The basic idea behind selective multiscale reconstruction of functions from error- afiected data is outlined on the sphere. The selective reconstruction mechanism is based on the premise that multiscale approximation can be well-represented in terms of only a relatively small number of expansion coeficients at various resolution levels. An attempt is made within a tree algorithm (pyramid scheme) to remove the noise component from each scale coefilient usinga priori statistical information (provided by an error covariance kernel of a Gaussian, stationary stochastic model)

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Introduction In modern cities, exposure to potentially risky noise levels is unavoidable. This important stressor might be responsible for several disorders that affect all body systems, especially the nervous system [ 1 ]. Several studies suggest

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Ground Penetrating Radar (GPR) is largely used nowadays in civil engineering applications as an effective technique of structural monitoring. This paper describes a method using radargram acquired by the GPR for estimating the radius of a steel rebar buried in a concrete massif, which is assumed to be homogeneous and isotopic. Considering the forward problem under B-scan procedure, a closed form mathematical formula was derived for the hyperbola trace appearing as the diffraction pattern provided by a circular steel bar. This equation relates the observed hyperbola parameters in the obtained radargram to the characteristics of the object and those of the host medium where the object is buried. The inverse problem was solved in two steps. Using the extracted raw data in terms of the hyperbola characteristics and Hough transform, the coordinates of the peak hyperbola are identified. Then the wave speed, the rebar radius as well as the coordinates of the rebar centre are estimated by a curve fitting procedure which is based on the selection of an arbitrary set of points on the considered hyperbola. The effect of noise resulting from variations affecting the electromagnetic wave speed was assessed. The noise was assumed to be a random variable and to act additively on the actual ordinates of the hyperbola. The obtained results have shown that the estimation of the rebar radius is very sensitive to the considered level of noise. Noise impedes the retrieval of a bar radius if its magnitude exceeds 5%.

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. Johnson M. T., Povinelli R. T., Generalized phase space projection for nonlinear noise reduction. Physica D 201 (2005) pp. 306–317. Povinelli R. T. Generalized phase space projection for

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by discouraging excessively intricate solutions [ 3 ]. While traditional methods like L1 and L2 regularization have been extensively explored and applied [ 4 ], recent years have witnessed a paradigm shift towards considering noise as a regularization

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pressure, noisiness, loudness 1984 Hunyadi D. The interpretation of the subjective road traffic noise annoyance, (in Hungarian

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Interventional Medicine and Applied Science
Authors:
Masoumeh Dorri Giv
,
Karim Ghazikhanlou Sani
,
Majid Alizadeh
,
Ali Valinejadi
, and
Hesamedin Askari Majdabadi

Introduction Noise pollution is an unwanted or undesirable sound in peripheral environment. In other words, it is indefinite and irregular combination of sounds [ 1 ]. Noise pollution has many effects on humans, including

Open access
Pollack Periodica
Authors:
Osman Metalla
,
Marsida Klemo
,
Azem Hysa
,
Elvis Çela
,
Abdullah Diku
, and
Migena Nako

1 Introduction Noise pollution and air pollution are serious environmental issues in many cities of the world. This has not been appropriately acknowledged even though it is steadily growing in developing

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. [7] Miloudi M. , Bendaoud A. , Miloudi H. , Nemmich S. , Slimani H. Analysis and reduction of common-mode and differential-mode EMI noise in a fly

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Acta Oeconomica
Authors:
Gergely Csurilla
,
András Gyimesi
,
Erika Kendelényi-Gulyás
, and
Tamás Sterbenz

). Fig. 1. The trend of the noise-factor (measured by NMSE of the ZIB 2 lag model) for different Olympic sports and years Sport event hosting is not the only field where

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