Instrumentation & Measurement Magazine 24-2 - 98

Fig. 5. Steps needed for the classification of a harvester based on sound recording. (a) Using a conventional neural network. (b) Using a convolutional neural
network.

can have great effect on preparing the data to be suitable for
training [47]. Normalization was done by dividing the above
features by the total number of frequency samples N used:
fi 

f
i for i = 1,2, ...,6.
N

As a classifier, a neural network with one hidden layer with
five nodes using backpropagation for training yielded accuracies of 78.26 when using 5000 samples of audio segments. The
total time required for feature extraction and final classification was 2.5 ms using an Asus laptop with a 64-bit Intel i7 CPU
@ 2.6 GHz and 16 GB of ram. We used the Matlab platform version 2017b using parallel processing via an NVIDIA GeForce
GTX 960 M GPU card with 10 Gb of memory. Fig. 5a shows the
steps taken.
98	

Classification Based on a CNN
The absolute value of the Short-Time Fourier Transform
(STFT), known as the Spectogram (SG) was used to obtain images. A seven-layer CNN was used. The layers are:
1.	Image input layer with 'zerocenter' normalization
2.	Convolution layer, eight 8x8x3 convolutions with stride
[1 1] and no padding
3.	ReLU layer
4.	Average Pooling layer with 2x2 average pooling with
stride [2 2] and no padding
5.	Fully Connected layer
6.	Softmax
7.	Classification Output layer, crossentropyex
Using the same number of samples as before, the CNN
achieved accuracies of 97.97 in an execution time below the

IEEE Instrumentation & Measurement Magazine	

April 2021



Instrumentation & Measurement Magazine 24-2

Table of Contents for the Digital Edition of Instrumentation & Measurement Magazine 24-2

No label
Instrumentation & Measurement Magazine 24-2 - No label
Instrumentation & Measurement Magazine 24-2 - Cover2
Instrumentation & Measurement Magazine 24-2 - 1
Instrumentation & Measurement Magazine 24-2 - 2
Instrumentation & Measurement Magazine 24-2 - 3
Instrumentation & Measurement Magazine 24-2 - 4
Instrumentation & Measurement Magazine 24-2 - 5
Instrumentation & Measurement Magazine 24-2 - 6
Instrumentation & Measurement Magazine 24-2 - 7
Instrumentation & Measurement Magazine 24-2 - 8
Instrumentation & Measurement Magazine 24-2 - 9
Instrumentation & Measurement Magazine 24-2 - 10
Instrumentation & Measurement Magazine 24-2 - 11
Instrumentation & Measurement Magazine 24-2 - 12
Instrumentation & Measurement Magazine 24-2 - 13
Instrumentation & Measurement Magazine 24-2 - 14
Instrumentation & Measurement Magazine 24-2 - 15
Instrumentation & Measurement Magazine 24-2 - 16
Instrumentation & Measurement Magazine 24-2 - 17
Instrumentation & Measurement Magazine 24-2 - 18
Instrumentation & Measurement Magazine 24-2 - 19
Instrumentation & Measurement Magazine 24-2 - 20
Instrumentation & Measurement Magazine 24-2 - 21
Instrumentation & Measurement Magazine 24-2 - 22
Instrumentation & Measurement Magazine 24-2 - 23
Instrumentation & Measurement Magazine 24-2 - 24
Instrumentation & Measurement Magazine 24-2 - 25
Instrumentation & Measurement Magazine 24-2 - 26
Instrumentation & Measurement Magazine 24-2 - 27
Instrumentation & Measurement Magazine 24-2 - 28
Instrumentation & Measurement Magazine 24-2 - 29
Instrumentation & Measurement Magazine 24-2 - 30
Instrumentation & Measurement Magazine 24-2 - 31
Instrumentation & Measurement Magazine 24-2 - 32
Instrumentation & Measurement Magazine 24-2 - 33
Instrumentation & Measurement Magazine 24-2 - 34
Instrumentation & Measurement Magazine 24-2 - 35
Instrumentation & Measurement Magazine 24-2 - 36
Instrumentation & Measurement Magazine 24-2 - 37
Instrumentation & Measurement Magazine 24-2 - 38
Instrumentation & Measurement Magazine 24-2 - 39
Instrumentation & Measurement Magazine 24-2 - 40
Instrumentation & Measurement Magazine 24-2 - 41
Instrumentation & Measurement Magazine 24-2 - 42
Instrumentation & Measurement Magazine 24-2 - 43
Instrumentation & Measurement Magazine 24-2 - 44
Instrumentation & Measurement Magazine 24-2 - 45
Instrumentation & Measurement Magazine 24-2 - 46
Instrumentation & Measurement Magazine 24-2 - 47
Instrumentation & Measurement Magazine 24-2 - 48
Instrumentation & Measurement Magazine 24-2 - 49
Instrumentation & Measurement Magazine 24-2 - 50
Instrumentation & Measurement Magazine 24-2 - 51
Instrumentation & Measurement Magazine 24-2 - 52
Instrumentation & Measurement Magazine 24-2 - 53
Instrumentation & Measurement Magazine 24-2 - 54
Instrumentation & Measurement Magazine 24-2 - 55
Instrumentation & Measurement Magazine 24-2 - 56
Instrumentation & Measurement Magazine 24-2 - 57
Instrumentation & Measurement Magazine 24-2 - 58
Instrumentation & Measurement Magazine 24-2 - 59
Instrumentation & Measurement Magazine 24-2 - 60
Instrumentation & Measurement Magazine 24-2 - 61
Instrumentation & Measurement Magazine 24-2 - 62
Instrumentation & Measurement Magazine 24-2 - 63
Instrumentation & Measurement Magazine 24-2 - 64
Instrumentation & Measurement Magazine 24-2 - 65
Instrumentation & Measurement Magazine 24-2 - 66
Instrumentation & Measurement Magazine 24-2 - 67
Instrumentation & Measurement Magazine 24-2 - 68
Instrumentation & Measurement Magazine 24-2 - 69
Instrumentation & Measurement Magazine 24-2 - 70
Instrumentation & Measurement Magazine 24-2 - 71
Instrumentation & Measurement Magazine 24-2 - 72
Instrumentation & Measurement Magazine 24-2 - 73
Instrumentation & Measurement Magazine 24-2 - 74
Instrumentation & Measurement Magazine 24-2 - 75
Instrumentation & Measurement Magazine 24-2 - 76
Instrumentation & Measurement Magazine 24-2 - 77
Instrumentation & Measurement Magazine 24-2 - 78
Instrumentation & Measurement Magazine 24-2 - 79
Instrumentation & Measurement Magazine 24-2 - 80
Instrumentation & Measurement Magazine 24-2 - 81
Instrumentation & Measurement Magazine 24-2 - 82
Instrumentation & Measurement Magazine 24-2 - 83
Instrumentation & Measurement Magazine 24-2 - 84
Instrumentation & Measurement Magazine 24-2 - 85
Instrumentation & Measurement Magazine 24-2 - 86
Instrumentation & Measurement Magazine 24-2 - 87
Instrumentation & Measurement Magazine 24-2 - 88
Instrumentation & Measurement Magazine 24-2 - 89
Instrumentation & Measurement Magazine 24-2 - 90
Instrumentation & Measurement Magazine 24-2 - 91
Instrumentation & Measurement Magazine 24-2 - 92
Instrumentation & Measurement Magazine 24-2 - 93
Instrumentation & Measurement Magazine 24-2 - 94
Instrumentation & Measurement Magazine 24-2 - 95
Instrumentation & Measurement Magazine 24-2 - 96
Instrumentation & Measurement Magazine 24-2 - 97
Instrumentation & Measurement Magazine 24-2 - 98
Instrumentation & Measurement Magazine 24-2 - 99
Instrumentation & Measurement Magazine 24-2 - 100
Instrumentation & Measurement Magazine 24-2 - 101
Instrumentation & Measurement Magazine 24-2 - 102
Instrumentation & Measurement Magazine 24-2 - 103
Instrumentation & Measurement Magazine 24-2 - 104
Instrumentation & Measurement Magazine 24-2 - 105
Instrumentation & Measurement Magazine 24-2 - 106
Instrumentation & Measurement Magazine 24-2 - 107
Instrumentation & Measurement Magazine 24-2 - 108
Instrumentation & Measurement Magazine 24-2 - 109
Instrumentation & Measurement Magazine 24-2 - 110
Instrumentation & Measurement Magazine 24-2 - 111
Instrumentation & Measurement Magazine 24-2 - 112
Instrumentation & Measurement Magazine 24-2 - 113
Instrumentation & Measurement Magazine 24-2 - 114
Instrumentation & Measurement Magazine 24-2 - 115
Instrumentation & Measurement Magazine 24-2 - 116
Instrumentation & Measurement Magazine 24-2 - 117
Instrumentation & Measurement Magazine 24-2 - 118
Instrumentation & Measurement Magazine 24-2 - 119
Instrumentation & Measurement Magazine 24-2 - 120
Instrumentation & Measurement Magazine 24-2 - 121
Instrumentation & Measurement Magazine 24-2 - 122
Instrumentation & Measurement Magazine 24-2 - 123
Instrumentation & Measurement Magazine 24-2 - 124
Instrumentation & Measurement Magazine 24-2 - 125
Instrumentation & Measurement Magazine 24-2 - 126
Instrumentation & Measurement Magazine 24-2 - 127
Instrumentation & Measurement Magazine 24-2 - 128
Instrumentation & Measurement Magazine 24-2 - 129
Instrumentation & Measurement Magazine 24-2 - 130
Instrumentation & Measurement Magazine 24-2 - 131
Instrumentation & Measurement Magazine 24-2 - 132
Instrumentation & Measurement Magazine 24-2 - Cover3
Instrumentation & Measurement Magazine 24-2 - Cover4
https://www.nxtbook.com/allen/iamm/25-9
https://www.nxtbook.com/allen/iamm/25-8
https://www.nxtbook.com/allen/iamm/25-7
https://www.nxtbook.com/allen/iamm/25-6
https://www.nxtbook.com/allen/iamm/25-5
https://www.nxtbook.com/allen/iamm/25-4
https://www.nxtbook.com/allen/iamm/25-3
https://www.nxtbook.com/allen/iamm/instrumentation-measurement-magazine-25-2
https://www.nxtbook.com/allen/iamm/25-1
https://www.nxtbook.com/allen/iamm/24-9
https://www.nxtbook.com/allen/iamm/24-7
https://www.nxtbook.com/allen/iamm/24-8
https://www.nxtbook.com/allen/iamm/24-6
https://www.nxtbook.com/allen/iamm/24-5
https://www.nxtbook.com/allen/iamm/24-4
https://www.nxtbook.com/allen/iamm/24-3
https://www.nxtbook.com/allen/iamm/24-2
https://www.nxtbook.com/allen/iamm/24-1
https://www.nxtbook.com/allen/iamm/23-9
https://www.nxtbook.com/allen/iamm/23-8
https://www.nxtbook.com/allen/iamm/23-6
https://www.nxtbook.com/allen/iamm/23-5
https://www.nxtbook.com/allen/iamm/23-2
https://www.nxtbook.com/allen/iamm/23-3
https://www.nxtbook.com/allen/iamm/23-4
https://www.nxtbookmedia.com