We present a modified commercial L-4C geophone with interferometric readout that demonstrated resolution 60 times lower than the included coil-magnet at low frequencies. The intended application for sensor is in vibration isolation platforms require improved performance frequencies 1 Hz. A controls and noise-model of an Advanced LIGO 'HAM-ISI' system was developed, it shows our can reduce resid...

background : noise pollution is one of the important issues of pollutant in workplaces and is almost one of the harmful agents for workers. at present, instrumental based inspections for determining the index levels of noise in workshops is performed. this method is requiring a time consuming and ex-pensive in large scale inspection for workplaces. classification of workplaces based on noise po...

noise is defined as unwanted or objectionable sound. human susceptibility to noise varies in terms of intensity, altitude, timbre of sound, personal sensibility, age, and history of ear disorder. noise pollution which is the result of heterogeneous and uncontrolled developments of cities is one the serious problems in large cities of iran. although noise pollution in kerman (located in southeas...

acoustic experimental data of irib (islamic republic of iran broadcasting) server room was taken to measure the acoustic noise characteristics of frequency and sound pressure level (spl). the purposes of this paper are measuring the noise pollution and its evaluation through the regulations. the measurements were taken in two stages. the first one was taken at 10 points by sound investigator 22...

We will review some of the recent advances in the field of acoustic and elastic metamaterials. These research fields became hot topics in last few years with an increasing number of papers that grows almost exponentially. The interest on these artificial structures arouses because of their potential application in designing novel devices for sound and vibration control. Their applications cover...

Interest in SOI technology has been increased due to recent progress in modeling parasitic effects needed for analog IC design. In this paper a brief overview of the SOI technology is done. A user compiled model built for ADS is then described before the analysis of 2 RF designs: a wideband Low Noise Amplifier (300MHz-900MHz with more than 10dB gain and 5dBm IIP3) and an antenna switch (with 0....

Low noise underground environments offer conditions allowing to assess ultimate performance of high sensitivity sensors such as accelerometers, gyrometers, seismometers... Such facilities are for instance ideal for observing the tiny signals of interest for geophysical studies. Laboratoire Souterrain à Bas Bruit (LSBB) in which we have installed our cold atom gravimeter, provides such an enviro...

A decentralized failure detection and isolation (FDI) methodology, which is robust with respect to model uncertainties and noise, is presented. Redundancy metrics are developed, and optimization problems are posed for the choices of robust parity relations. Closed-form solutions for some special failure cases are given. Connections are drawn with other disciplines, and the use of the metrics to...

Scanning probe microscopes are notoriously susceptible to disturbances, or mechanical noise, from the surrounding environment that couple to the probe–sample interaction. These disturbances include vibrations of mechanical components, piezo drift, and thermal expansion. Disturbance effects can be substantially reduced by designing a rigid microscope, incorporating effective vibration isolation,...