Table 4 The denoising effect of pso - omp algorithm on different types of noise.
From: Time frequency analysis of elastic wave PSO OMP for defects in flat steel of down conductors
Width(mm) | Type of noise | Parament of noise | Evaluation |
|---|---|---|---|
1 | Gaussian noise | SNR = 5 dB | SNR improvement = 18.5 dB, positioning error = 6.2%, computation time = 1.1 s |
1 | Impulse noise | Density = 10% Amp = 50%peak value | SNR improvement = 14.3 dB, positioning error = 8.5%, computation time = 1.3 s |
1 | Mechanical Vibration noise | Fre rang=[50–200]Hz Amp = 0.3 mm | SNR improvement = 12.8 dB, positioning error = 9.7%, computation time = 1.0 s |
1 | Mixed noise | The sum of above three | SNR improvement = 11.2 dB, positioning error = 12.4%, computation time = 1.5 s |
2 | Gaussian noise | SNR = 10 dB | SNR improvement = 20.1 dB, positioning error = 4.8%, computation time = 1.2 s |
2 | Impulse noise | Density = 15% Amp = 80%peak value | SNR improvement = 13.5 dB, positioning error = 7.1%, computation time = 1.4 s |
2 | Mechanical Vibration noise | Fre rang=[100–300]Hz Amp = 0.2 mm | SNR improvement = 15.6 dB, positioning error = 6.9%, computation time = 1.1 s |
2 | Mixed noise | The sum of above three | SNR improvement = 9.8 dB, positioning error = 14.3%, computation time = 1.6 s |
3 | Gaussian noise | SNR = 15 dB | SNR improvement = 22.4 dB, positioning error = 3.5%, computation time = 1.0 s |
3 | Impulse noise | Density = 5% Amp = 30%peak value | SNR improvement = 16.0 dB, positioning error = 5.2%, computation time = 1.2 s |
3 | Mechanical Vibration noise | Fre rang=[20–500]Hz Amp = 0.5 mm | SNR improvement = 10.3 dB, positioning error = 11.5%, computation time = 1.3 s |
3 | Mixed noise | The sum of above three | SNR improvement = 8.1 dB, positioning error = 16.8%, computation time = 1.7 s |
4 | Gaussian noise | SNR = 7 dB | SNR improvement = 19.3 dB, positioning error = 5.7%, computation time = 1.1 s |
4 | Impulse noise | Density = 20% Amp = 100%peak value | SNR improvement = 12.7 dB, positioning error = 9.3%, computation time = 1.5 s |
4 | Mechanical Vibration noise | Fre rang=[200–400]Hz Amp = 0.4 mm | SNR improvement = 14.0 dB, positioning error = 7.8%, computation time = 1.2 s |
4 | Mixed noise | The sum of above three | SNR improvement = 18.5 dB, positioning error = 6.2%, computation time = 1.1 s |
5 | Gaussian noise | SNR = 3 dB | SNR improvement = 16.8 dB, positioning error = 7.9%, computation time = 1.3 s |
5 | Impulse noise | Density = 25% Amp = 60%peak value | SNR improvement = 11.5 dB, positioning error = 10.6%, computation time = 1.6 s |
5 | Mechanical Vibration noise | Fre rang=[300–500]Hz Amp = 0.1 mm | SNR improvement = 17.2 dB, positioning error = 5.4%, computation time = 1.0 s |
5 | Mixed noise | The sum of above three | SNR improvement = 7.5 dB, positioning error = 18.2%, computation time = 1.8 s |
