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Geoff McDonald

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Files Posted by Geoff View all
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14 Nov 2012 Screenshot Maximum Correlated Kurtosis Deconvolution (MCKD) A method to extract periodic impulses from a 1d signal. Author: Geoff McDonald correlated kurtosis, maximum correlated ku..., mckd, fault detection, deconvolution, gear fault 20 1
  • 4.0
4.0 | 1 rating
18 Feb 2011 Screenshot Minimum Entropy Deconvolution (MED 1D and 2D) Generates a 1D FIR filter iteratively to minimize the entropy of the filtered signal(s). Author: Geoff McDonald minimum entropy decon..., deconvolution, 1d, med, dsp, signal processing 18 6
  • 4.0
4.0 | 2 ratings
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08 Jun 2012 Minimum Entropy Deconvolution (MED 1D and 2D) Generates a 1D FIR filter iteratively to minimize the entropy of the filtered signal(s). Author: Geoff McDonald

I just thought I would note that the Stat toolbox is not needed anymore. I updated this to implement the kurtosis() function internally.
31 Oct 2010 Minimum Entropy Deconvolution (MED 1D and 2D) Generates a 1D FIR filter iteratively to minimize the entropy of the filtered signal(s). Author: Geoff McDonald

Thanks Bruno. I forgot the kurtosis() function was from the statistical toolbox. I will update the description to include it as a requirement, or just code the kurtosis function myself.
28 Oct 2010 Minimum Entropy Deconvolution (MED 1D and 2D) Generates a 1D FIR filter iteratively to minimize the entropy of the filtered signal(s). Author: Geoff McDonald

If anyone would like the 2D MED implementation, just let me know and I will work on adding it to this file. I don't need the 2d approach for my work, and I want to make sure someone else would get use out of the extension before working at.
29 Sep 2010 Entropy Calculates the sample entropy, in bits, of discrete variables. Author: Will Dwinnell

Oh, I would just like to note that the below code will only work for 1d vectors, ie. Nx1 or 1xN.
29 Sep 2010 Entropy Calculates the sample entropy, in bits, of discrete variables. Author: Will Dwinnell

I had serious trouble with the performance of this entropy calculation method. For about 500k samples it takes about 20 seconds to compute the entropy. Here is an alternative entropy function I just wrote up for integer signal values (ie. y = [1 -6011 -3000 2592]):

function [ent] = EntropyInt(y)
% Calculate the entropy for an integer value of y

% First verify that y is truely integer-valued
Sum = sum(y);
if( Sum ~= round(Sum) )
error('INTEGER_ENTROPY:InvalidInput', 'Input arguments must be of integer value.')
end

% Generate the histogram
[n x] = hist(y, double(min(y):max(y)));

% Normalize the area of the histogram to make it a pdf
n = n / sum(n);

% Calculate the entropy
indices = n ~= 0;
ent = -sum(n(indices).*log2(n(indices)));
end
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22 Apr 2013 Minimum Entropy Deconvolution (MED 1D and 2D) Generates a 1D FIR filter iteratively to minimize the entropy of the filtered signal(s). Author: Geoff McDonald Minh

MED is a terrific algorithm and the author has made a very good job.

However, I found that improvement might be needed when dealing with large data or filter kernel. In such cases, calculation the cross-correlation using for-loop is extremely slow.

To improve, I used FFT-based cross correlation and the speed was hundred times faster. Anyone interested might look into Matlab's function xcorr.m and make your own improvement.
24 Jun 2012 Minimum Entropy Deconvolution (MED 1D and 2D) Generates a 1D FIR filter iteratively to minimize the entropy of the filtered signal(s). Author: Geoff McDonald Raj, Santhana

Good work....But I don understand why the author didnt use already existing functions like autocorr, corr, kurtosis and all... this implementation takes more time to execute...

24 Jun 2012 Maximum Correlated Kurtosis Deconvolution (MCKD) A method to extract periodic impulses from a 1d signal. Author: Geoff McDonald Raj, Santhana

Good work...

08 Jun 2012 Minimum Entropy Deconvolution (MED 1D and 2D) Generates a 1D FIR filter iteratively to minimize the entropy of the filtered signal(s). Author: Geoff McDonald McDonald, Geoff

I just thought I would note that the Stat toolbox is not needed anymore. I updated this to implement the kurtosis() function internally.
31 Oct 2010 Minimum Entropy Deconvolution (MED 1D and 2D) Generates a 1D FIR filter iteratively to minimize the entropy of the filtered signal(s). Author: Geoff McDonald McDonald, Geoff

Thanks Bruno. I forgot the kurtosis() function was from the statistical toolbox. I will update the description to include it as a requirement, or just code the kurtosis function myself.
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deconvolution, 1d, 2d, bearing fault, ck
Files Tagged by Geoff View all
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Updated   File Tags Downloads
(last 30 days) 		Comments Rating
14 Nov 2012 Screenshot Maximum Correlated Kurtosis Deconvolution (MCKD) A method to extract periodic impulses from a 1d signal. Author: Geoff McDonald correlated kurtosis, maximum correlated ku..., mckd, fault detection, deconvolution, gear fault 20 1
  • 4.0
4.0 | 1 rating
18 Feb 2011 Screenshot Minimum Entropy Deconvolution (MED 1D and 2D) Generates a 1D FIR filter iteratively to minimize the entropy of the filtered signal(s). Author: Geoff McDonald minimum entropy decon..., deconvolution, 1d, med, dsp, signal processing 18 6
  • 4.0
4.0 | 2 ratings

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