An original novelty detection algorithm in the Fourier domain, using extreme value theory (EVT) is considered in this article. Periodograms may be considered as frequency-dependent random variables, and this can be taken into account when designing statistical tests. Frequency-Dependent Peak-Over-Threshold (FDPOT) puts special emphasis on the frequency dependence of extreme value statistics, th...

The vibrations of rotating machinery are produced by a combination of periodic and random processes due to the machine's rotation cycle and interaction with the real world. The combination of such components can give rise to signals which have periodically time-varying ensemble statistics and are best considered as cyclostationary. In this paper, second-order cyclic statistical methods are desc...

We analyze experimentally and theoretically mechanical oscillation within an optical cavity stimulated by the pressure of circulating optical radiation. The resulting radio frequency cavity vibrations (phonon mode) cause modulation of the incident, continuous-wave (cw) input pump beam. Furthermore, with increasing cw pump power, an evolution from sinusoidal modulation to random oscillations is ...

Because the underlying physiology of pathological tremor in a Parkinson's patient is not well understood, the existing physical and drug therapies have not been successful in tremor treatment. Different mathematical modeling of such vibration has been introduced to investigate the problem and reduce the existing vibration. Most of the models have represented the induced vibration as a sinusoida...

Arterial bleeding into a free space is known to cause local vibrations in tissue. To study the effectiveness of utilizing these tissue vibrations in localizing the site of arterial bleeding, we have developed an algorithm for ultrasonically imaging these tissue vibrations. Simulation results indicate that our algorithm can correctly detect vibrations in the presence of pulsatile wall motion, bl...

Flow induced vibrations are an important concern in the design of nuclear reactors. One of the possible designs of the 4th generation nuclear reactors is a lead-cooled fast reactor of which MYYRHA is a prototype. The combination of high liquid density, flow velocity, low pitch-todiameter ratio and the absence of grid spacers makes this design prone to flow induced vibrations. Although most vibr...

The purpose of introducing ultrasonic vibrations in the tube hydroforming process is to create more formability by obtaining a lower corner radius, improve thickness distribution of the wall and provide good tribological conditions at the tube and the die interface. Vibrations imposed on the die create alternating gaps which improve the formability in the tube hydroforming process in the presen...

The cross-plane thermal conductivity of thin films of WSe2 grown from alternating W and Se layers is as small as 0.05 watts per meter per degree kelvin at room temperature, 30 times smaller than the c-axis thermal conductivity of single-crystal WSe2 and a factor of 6 smaller than the predicted minimum thermal conductivity for this material. We attribute the ultralow thermal conductivity of thes...

The article presents resarches for designing and manufacturing of the ultrasonic motors that uses piezoceramic materials. There are presented specific vibrations modes for the studied piezoceramic plates, vibrations that are used to excite the motor activated element (mobile element). Using the finite element method it is really posssible to predict the usefull vibrations that can makes easier ...

a linear superposition method was used for modeling the time history of the production blast vibrations and optimizing the blast sequence to reduce vibration levels in sar-cheshmeh copper mine, kerman, iran. a single-hole blast for modeling and two double-hole blasts with time delays of 25 and 65 ms between two holes for modeling validation were carried out. the generated vibrations were measur...