Submerged passive acoustic technology allows researchers to investigate spatial and temporal movement patterns of many marine and freshwater species. The technology uses receivers to detect and record acoustic transmissions emitted from tags attached to an individual. Acoustic signal strength naturally attenuates over distance, but numerous environmental variables also affect the probability a ...

Common acoustic partial discharge (PD) and vibration measurements use sensors attached on the outside tank wall of (power) transformers. Hereby, tank structure can lead to severe signal damping which in practice often leads to acoustic PD signals below noise level. Scope of the work is an acoustic and ultra-high frequency (UHF) detection of PD and additional recording of transformer vibrations ...

Two different signal processing algorithms are described for detection and classification of acoustic signals generated by firearm discharges in small enclosed spaces. The first is based on the logarithm of the signal energy. The second is a joint entropy. The current study indicates that a system using both signal energy and joint entropy would be able to both detect weapon discharges and clas...

High background noise is an important obstacle in successful signal detection and perception of an intended acoustic signal. To overcome this problem, many animals modify their acoustic signal by increasing the repetition rate, duration, amplitude or frequency range of the signal. An alternative method to ensure successful signal reception, yet to be tested in animals, involves the use of two d...

Traditional high-voltage reactor monitoring and diagnosis research has problems such as high sampling demand, difficulty in noise reduction on site, many false alarms, lack of on-site data. In order to solve the above problems, this paper proposes an acoustic–electric fusion acquisition system defect method based pulse current ultrasonic detection signal. Using envelope peak signal basic data, ...

Although traditional signal-based structural health monitoring algorithms have been successfully employed for small structures, their application for large and complex bridges has been challenging due to non-stationary signal characteristics with a high level of noise. In this paper, a promising damage detection algorithm is proposed by incorporation of adaptive signal processing and Artificial...

Challenges in signal detection in the presence of noise arise in many underwater acoustic applications such as active and passive sonar, geophysical surveying, and marine life monitoring. The detection problem is generally formulated within the framework of binary hypothesis testing. An important class of detectors, known as the locally optimum detectors, are designed based on the expectation t...

The main purpose of this paper is to develop the method of characteristic functions for calculating the detection characteristics in the case of the object surrounded by rough surfaces. This method is to be implemented in synthetic aperture radar (SAR) systems using optimal resolution algorithms. By applying the specified technique, the expressions have been obtained for the false alarm and cor...