The information gathered from sensors is used to determine the health of a sensor. Once a normal mode of operation is established any deviation from the normal behavior indicates a change. This change may be due to a malfunction of the sensor(s) or the system (or process). The step-up and step-down features, as well as sensor disturbances are assumed to be exponential. An RC network is used to ...

Shift and rotation invariance properties of linear time-frequency representations are investigated. It is shown that among all linear time-frequency representations, only the short-time Fourier transform (STFT) family with the Hermite–Gaussian kernels satisfies both the shift invariance and rotation invariance properties that are satisfied by the Wigner distribution (WD). By extending the time-...

The Fourier transform is often used to connect the Lorentzian energy distribution for resonance scattering to the exponential time dependence for decaying states. However, to apply the Fourier transform, one has to bend the rules of standard quantum mechanics; the Lorentzian energy distribution must be extended to the full real axis −∞ < E < ∞ instead of being bounded from below 0 ≤ E < ∞ (“Fer...

A Review on Vibration Analysis for Misalignment of Shaft in Rotary Systems by Using Discrete Wavelet Transform Abhijeet Shirude | S. Y. Gajjal (Mechanical Department, NBNSSoE, Savitribai Phule Pune University, Pune, India, [email protected]) (Mechanical Department, NBNSSoE, Savitribai Phule Pune University, Pune, India, [email protected]) ___________________________________________...

This chapter covers the fundamental principles and current applications of Fourier transform (FT) infrared and Fourier transform Raman spectroscopies as utilized in the analysis of polymeric materials. The primary emphasis of the first part is on the principles and advantages of these interferometric methods, whereas the remaining sections illustrate numerous applications focusing on the struct...

In this work, a new mathematical model of thermoelasticity theory has been considered in the context of a new consideration of heat conduction with fractional order theory. A functionally graded isotropic unbounded medium is considered subjected to a periodically varying heat source in the context of space-time non-local generalization of three-phase-lag thermoelastic model and Green-Naghdi mod...

Laser AE method is a non-contact AE detection technique, which utilizes laser interferometer as sensor. This method is less subjected to environmental difficulties and can be adaptive for wider target than conventional PZT sensors. However, laser AE method has to improve its sensitivity because the noise level of laser interferometer is higher than PZT sensors. In this study, a method to reduce...