Authors:
Juan José González de la Rosa
1
;
José Melgar Camarero
1
;
Stephane Bouaud
1
;
J. G. Ramiro
1
and
Antonio Moreno Muñoz
2
Affiliations:
1
Univ. Cádiz, Spain
;
2
Univ. Córdoba, Spain
Keyword(s):
Acoustic Emission, Discrete Wavelet Transform, Higher-Order Statistics, Insect detection, Spectral kurtosis, Transient detection.
Related
Ontology
Subjects/Areas/Topics:
Biomedical Engineering
;
Biomedical Signal Processing
;
Computer Vision, Visualization and Computer Graphics
;
Feature Extraction
;
Features Extraction
;
Image and Video Analysis
;
Informatics in Control, Automation and Robotics
;
Nonlinear Signals and Systems
;
Signal Processing, Sensors, Systems Modeling and Control
;
Time and Frequency Response
;
Time-Frequency Analysis
Abstract:
In this paper we present the operation results of a portable computer-based measurement equipment conceived to perform non-destructive testing of suspicious termite infestations. Its signal processing module is based in the spectral kurtosis (SK), with the de-noising complement of the discrete wavelet transform (DWT). The SK pattern allows the targeting of alarms and activity signals. The DWT complements the SK, by keeping the successive approximations of the termite emissions, supposed more non-gaussian (less noisy) and with less entropy than the detail approximations. For a given mother wavelet, the maximum acceptable level, in the wavelet decomposition tree, which preserves the insects’ emissions features, depends on the comparative evolution of the approximations details’ entropies, and the value of the global spectral kurtosis associated to the approximation of the separated signals. The paper explains the detection criterion by showing different types of real-life recordings (a
larms, activity, and background).
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