in this paper, a smart method is designed in order to classify healthy and illness ducks using their emission voice. for this purpose, firstly, the birds based on their healthy condition are divided into the different categories and then their voices are saved using a microphone and data acquisition card. gained signals were transformed from time-domain signal to frequency domain using fast fou...

Inverse Transient Analysis (ITA) is a powerful approach for leak detection of pipelines. When the pipe transient flow is analyzed in frequency domain the ITA is called Inverse Frequency Response Analysis (IFRA). To implement an IFRA for leak detection, a transient state is initiated in the pipe by fast closure of the downstream end valve. Then, the pressure time history at the valve location is...

Image processing is a recent trend that is grabbing attention in almost all areas like space, medical, defence, authentication systems etc. ,. Discrete Fourier Transforms is one of the most used transforms in image processing. Discrete Fourier Transform helps to transform the signal from spatial domain to frequency domain which is often used for filtering, correlation analysis and spectrum anal...

In the next two lectures, we will continue to expand our toolbox for computing in frequency domain, by adding two important computational tools. The first, the Fast Fourier Transform (FFT) is a family of algorithms for efficiently computing the Discrete Fourier Transform. These algorithms are of great practical importance, as theymake it possible to perform frequency domain analysis of very lar...

This paper is concerned with a synthesis study of the fast Fourier transform (FFT), the short time Fourier transform (STFT and the Wigner distribution (WD) in analysing the phonocardiogram signal (PCG) or heart cardiac sounds.     The FFT (Fast Fourier Transform) can provide a basic understanding of the frequency contents of the heart sounds. The STFT is obtained by calculating the Fourier tran...

At high speed, there are two problems for safety and effective control of vehicles. One is that Signal-to-noise of wheel speed sensors are reduced, and the other is the data calculated by wheel speed signal is emanative. In this paper, wheel speed sensor signal was transformed into a frequency domain by using Fast Fourier Transformation (FFT) or Inverse Fast Fourier Transform (IFFT), waveform f...

spectral decomposition is a powerful tool for analysis of seismic data. fourier transform determines the frequency contents of a signal. but for analysis of non-stationary signals, 1-d transform to frequency domain is not sufficient. in early years, transforming of seismic traces into time and frequency domain was done via windowed fourier transform, called a short time fourier transform (stft)...

in this paper, based on equations of lateral vibrations of wires, a non contact method for measuring instantaneous tension in a wire is introduced. the lateral vibration of the string is measured using an eddy current transducer and is sent to a computer. this signal is then imported to suitable software for fast fourier transform (fft) processing. the first natural frequency of the string is c...

this study represents an intelligence procedure for diagnosis simultaneously avian newcastle disease virus, infection bronchitis virus and influenza using heart sound signal. for this aim, the chickens were divided into four groups. the first group was considered as control samples. the second, third and fourth groups were infected with newcastle disease virus, infection bronchitis and avian in...