A match-filter method for measuring group velocity and attenuation in the laboratory

T-wave alternans (TWA) in surface electrocardiograph (ECG) signals has been recognized as a marker of cardiac electrical instability and is hypothesized to be associated with increased risk for ventricular arrhythmias among patients. A novel time-domain TWA hybrid analysis method (HAM) utilizing the correlation method and least squares regression technique is described in this paper. Simulated ECGs containing artificial TWA (cases of absence of TWA and presence of stationary or time-varying or phase-reversal TWA) under different baseline wanderings are used to test the method, and the results show that HAM has a better ability of quantifying TWA amplitude compared with the correlation method (CM) and adapting match filter method (AMFM). The HAM is subsequently used to analyze the clinical ECGs, and results produced by the HAM have, in general, demonstrated consistency with those produced by the CM and the AMFM, while the quantifying TWA amplitudes by the HAM are universally higher than those by the other two methods.

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Q estimation by a match-filter method

10.1190/segam2012-1257.1 ◽

2012 ◽

Cited By ~ 4

Author(s):

Peng Cheng ◽

Gary F. Margrave

Keyword(s):

Filter Method ◽

Match Filter

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Interferometric (Fourier-Spectroscopic) Measurement of Electron Energy Distributions

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100134144 ◽

1990 ◽

Vol 48 (2) ◽

pp. 110-111 ◽

Cited By ~ 1

Author(s):

F. Hasselbach ◽

A. Schäfer

Keyword(s):

Group Velocity ◽

Wave Packets ◽

Index Of Refraction ◽

Electron Wave ◽

Fringe Contrast ◽

Faraday Cage ◽

Optical Index ◽

Wien Filter ◽

Coherent Wave ◽

Electric And Magnetic Fields

Möllenstedt and Wohland proposed in 1980 two methods for measuring the coherence lengths of electron wave packets interferometrically by observing interference fringe contrast in dependence on the longitudinal shift of the wave packets. In both cases an electron beam is split by an electron optical biprism into two coherent wave packets, and subsequently both packets travel part of their way to the interference plane in regions of different electric potential, either in a Faraday cage (Fig. 1a) or in a Wien filter (crossed electric and magnetic fields, Fig. 1b). In the Faraday cage the phase and group velocity of the upper beam (Fig.1a) is retarded or accelerated according to the cage potential. In the Wien filter the group velocity of both beams varies with its excitation while the phase velocity remains unchanged. The phase of the electron wave is not affected at all in the compensated state of the Wien filter since the electron optical index of refraction in this state equals 1 inside and outside of the Wien filter.

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The four-dimensional group velocity

Uspekhi Fizicheskih Nauk ◽

10.3367/ufnr.0125.197807f.0549 ◽

1978 ◽

Vol 125 (7) ◽

pp. 549-565 ◽

Cited By ~ 19

Author(s):

V.G. Polevoi ◽

S.M. Rytov

Keyword(s):

Group Velocity ◽

Dimensional Group

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Improved Adaptive Hatch Filter Method to Minimize Effects of Ionospheric Anomaly for GBAS

2019 Chinese Control Conference (CCC) ◽

10.23919/chicc.2019.8866546 ◽

2019 ◽

Cited By ~ 1

Author(s):

Jie Hu ◽

Yongiie Yan ◽

Xiaozhu Shi

Keyword(s):

Filter Method

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Group velocity and propagation of numerical errors

10.2514/6.1972-153 ◽

1972 ◽

Cited By ~ 1

Author(s):

C. KENTZER

Keyword(s):

Group Velocity ◽

Numerical Errors

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Enhancing the Performance of One Dimensional Median Filter

Restaurant Business ◽

10.26643/rb.v118i7.7249 ◽

2019 ◽

Vol 118 (7) ◽

pp. 73-76

Author(s):

Sharanabasappa ◽

P Ravibabu

Keyword(s):

Impulse Noise ◽

Rank Order ◽

Median Filter ◽

Filter Method ◽

Salt And Pepper Noise ◽

Edge Preservation ◽

Word Level ◽

Look Ahead ◽

Filter Architecture ◽

Salt And Pepper

Nowadays, during the process of Image acquisition and transmission, image information data can be corrupted by impulse noise. That noise is classified as salt and pepper noise and random impulse noise depending on the noise values. A median filter is widely used digital nonlinear filter in edge preservation, removing of impulse noise and smoothing of signals. Median filter is the widely used to remove salt and pepper noise than rank order filter, morphological filter, and unsharp masking filter. The median filter replaces a sample with the middle value among all the samples present inside the sample window. A median filter will be of two types depending on the number of samples processed at the same cycle i.e, bit level architecture and word level architecture.. In this paper, Carry Look-ahead Adder median filter method will be introduced to improve the hardware resources used in median filter architecture for 5 window and 9 window for 8 bit and 16 bit median filter architecture.

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