The evaluation and control of the trains induced vibrations needs even more attention in the case of underground tracks which passes near to monuments and historical sites. The rail corrugations which occur due to the wheels’ impulse loads during the operation period of underground railway tracks, usually amplify the ground borne noise and vibration. In the current study, the mentioned phenomen...

Stepper motor performance can be compromised by noise and vibration, but an advanced high-torque micro-stepping algorithm can minimise the impact of both noise and vibration as well as increasing the resolution of the rotations. The embedded microcontroller which hosts the micro-stepper algorithm also provides additional flexibility to integrate current-limiting as well as adjusting the drive c...

Esophageal speakers, who produce a voice source by bringing about a vibration of the esophageal superior sphincter, must insufflate the esophagus with an air injection gesture before every utterance, thus creating an air reservoir to drive the vibration. The resulting noise is generally undesired by the speakers. This paper describes a method for the automatic recognition and rejection of the i...

A comparative study of vibration and acoustic noise reductions via electronic switching controls for switched reluctance motor (SRM) is presented. First, studies concerning the acoustic noise and vibration sources, their effects and the existing mitigation approaches are given. Then five switching control approaches, which belong to the magnetic and electronic remedies, are proposed and applied...

A study of the combined helicopter noise and vibration problem was conducted. A refined aerodynamic model capable of calculating the unsteady surface pressure distribution on rotor blade/flap combinations is developed and coupled with an aeroelastic analysis simulation code. An acoustic prediction tool based on WOPWOP is combined with the aeroelastic analysis based on a flexible blade with coup...

Oscillators operating in field applications are subject to much more strenuous environmental effects than those in the laboratory. These environmental effects, such as vibration and temperature fluctuation, have a great impact on the performance of the oscillators; however, many applications require this laboratory-level performance in situ. Opto-electronic oscillators (OEOs) have emerged in re...

Rotating machinery vibration analysis involves a convolute mixture because of the propagation medium, and the signals recorded by sensors in an industrial application are often disrupted by the environment. Deconvolution is a signal processing method for convolution of vibration sources, spectral kurtosis is a statistical tool which can indicate the presence of series of transients and their lo...