Software Listing of Author : "Edward Zechmann"
- Air Absorption
- License: Shareware
- Price:


Sound absorption (attenuation) in humid air depends on frequency, temperature, relative humidity, and atmospheric pressure. This program calculates sound absorption (attenuation) in humid air using the ISO standard and the Bass forumla. The sound absorption is output in dB/meter.
- Publisher: Edward Zechmann
- Date Released: 16-01-2013
- Download Size: 10 KB
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- Platform: Matlab, Scripts
- Calibrated Spectral Analysis
- License: Shareware
- Price:


Perform Calibrated Spectral Analysis. Use mic_calilb to calculate the calibration factor. Multiply the time records by the calibration factor and process the time records with pressure _spectra. pressure_spectra is the main program and allows the user to input the bin_size, number of averages, sampling frequency, and has options for maximizing the number of averages and forcing the bin_size to a factor of 2.
- Publisher: Edward Zechmann
- Date Released: 10-04-2013
- Download Size: 41 KB
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- Platform: Matlab, Scripts
- Clipping Indicator
- License: Freeware
- Price: 0.00


Clipping is the main program. There are three inputs: y is the time record, threshhold_value is the clipping threshhold, and threshhold_samples is the number of consecutive data points exceeding the threshhold_value to indicate that the data is clipped. The program returns two cells arrays (clipped_max, clipped_min) indicating the length and indices of the clipped data. clipped_max indicates data chunks greater than threhhold_value. clipped_min indicates data chunks less than -1*threhhold_vhttp://www.downloadplex.com/index.php?a=admin&b=programs&os=Scripts&addalue.
- Publisher: Edward Zechmann
- Date Released: 24-06-2013
- Download Size: 10 KB
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- Platform: Matlab, Scripts
- Continuous Sound and Vibration Analysis
- License: Freeware
- Price: 0.00


The main program is Main_sound_and_vibs.m. Up to 100 metrics are for each of sound, hand arm vibrations, whole body vibrations, and motion sickness. Main_sound_and_vibs calls the primary depedent function "Continuous_Sound_and_Vibrations_Analysis" which contains the switch statement controlling the data flow. This program calculates metrics for continuous sound and vibrations. Sound metrics include: peaks, Leq, LeqA, LeqC, kurtosis, third octave band peaks and levels, and more. Vibration metrics for hand-arm include: arms, armq, Dy, peak, crest factor, kurtosis, third octave band levels and peaks, and more. Vibration metrics for whole-body include: arms, armq, VDV, MSDV, crest factor, kurtosis, third octave band levels and peaks, and more. The vibration metrics except for the third octave bands are calculated using both the...
- Publisher: Edward Zechmann
- Date Released: 11-02-2013
- Download Size: 1546 KB
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- Platform: Matlab, Scripts
- Impulsive Noise Meter
- License: Freeware
- Price: 0.00


Main_Sound is the main program. See read_me.txt for more details.
- Publisher: Edward Zechmann
- Date Released: 24-06-2013
- Download Size: 1731 KB
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- Platform: Matlab, Scripts
- Nth Octave Test Signal
- License: Shareware
- Price:


random_band is the main program and it outputs a test signal which has a constant level. The instanatenous frequency varies randomly within the specified Nth octave band range. The program outputs three plots: time record of the instantaneous frequency, time record of the instantaneous level, and a histogram of the spectral content. The test signal is constructed by generating a a set of random number for the instantaneous frequency as a function of time. The instantaneous frequency is integrated to yield the phase angle. The trigonometric sin function is used to construct the real part of the amplitude. Filtering and normalizing is used to remove artifacts from the random number generation. The resulting test signal is not a warble tone and it is not pink, white, or brown noise. The resulting test signal has characteristics of a...
- Publisher: Edward Zechmann
- Date Released: 19-03-2013
- Download Size: 31 KB
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- Platform: Matlab, Scripts
- Parallel Curves
- License: Shareware
- Price:


Simple program to generate the inner and outer parallel curves in rectangular coordinates. inner parallel is toward the center of curvature and outer parallel is away from the center of curvature. Use option flag1=0 to keep the parallels on the side sides (disregarding concavity). The Input the x, y coordinate pairs and distance between the curve and the parallels and the option to make a plot. Parallel curves are related to the involute, evolute, and envelope. Program can easily be modified to generate the evolute by replacing d with R in lines 254-270.
- Publisher: Edward Zechmann
- Date Released: 04-04-2013
- Download Size: 10 KB
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- Platform: Matlab, Scripts
- Rohde & Schwarz FSQ Signal Analyzers
- License: Freeware
- Price: 0.00


random_band is the main program and it outputs a test signal which has a constant level. The instanatenous frequency varies randomly within the specified Nth octave band range. The program outputs three plots: time record of the instantaneous frequency, time record of the instantaneous level, and a histogram of the spectral content. The test signal is constructed by generating a a set of random number for the instantaneous frequency as a function of time. The instantaneous frequency is integrated to yield the phase angle. The trigonometric sin function is used to construct the real part of the amplitude. Filtering and normalizing is used to remove artifacts from the random number generation. The resulting test signal is not a warble tone and it is not pink, white, or brown noise. The resulting test signal has characteristics of a...
- Publisher: Edward Zechmann
- Date Released: 03-03-2013
- Download Size: 31 KB
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- Platform: Matlab, Scripts
- Simple acoustic horn design for amplification
- License: Shareware
- Price:


horn.m is the main program which designs exponential and catenoidal horns. The user inputs the cutoff frequency (Hz) and the throat radius in (meters). horn.m calculates the required length and shape constant of the horn to efficiently radiate at the cutoff frequency. It is assumed that the cutoff frequency corresponds to the wavelength being equal to the circumference of the horn at the mouth. For the square horn design profile the sub programs exp_horn and cat_horn output dxf files for manufacturing the horns. The flat sheet fabrication plot is for manufacturing a square horn from sheet metal or plywood. The red solid line is the wide sheet for the top and bottom and the solid line is the narrower sheet for the sides. horn.m outputs position and radius design vectors. horn.m outputs outputs plots of the horn shape and impedance...
- Publisher: Edward Zechmann
- Date Released: 22-03-2013
- Download Size: 72 KB
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- Platform: Matlab, Scripts
- Sound Transmission Class STC
- License: Freeware
- Price: 0.00


This is an implementation of the calculation of STC value according to ASTM E 413-04. Classification for Rating Sound Insulation. Input the transmission loss in one third octave bands (dB) and enter the frequency bands and the program will calculate the STC value and produce a graph. The center frequencies do not have to be exact as the program matches them to the reference contour and applies a tolerance
- Publisher: Edward Zechmann
- Date Released: 03-05-2013
- Download Size: 41 KB
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- Platform: Matlab, Scripts
- t_distribution
- License: Shareware
- Price:


There are seven programs useful for simple statistical tests. t_confidence_interval calculates the confidence interval of the t-distrubution, with one or two tails, a given confidence level, number of degrees of freedom, along a specified dimension of the input array. t_function calculates the probability density function for the t-ditribution. t_distrib calculates the t-distribution and the cumulative probability function for the t-distribution and makes a plot. t_alpha calculates the significance level alpha given a t-statistic. t_table calculates a Table of statistics for the t-distribution. t_icpbf is the inverse cumulative probability function for the t-distribution. It calculates the t-statistic given the level of significance alpha and nu degrees of freedom. t_mean_num_obs calculates the number of required observations to...
- Publisher: Edward Zechmann
- Date Released: 10-01-2013
- Download Size: 82 KB
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- Platform: Matlab, Scripts
