In this paper we address the problems of hysteresis and vibrations that limit the accuracy of piezoelectric positioners. It is widely known that the use of charge control significantly reduces hysteresis, thus enabling high-accuracy positioning during low speed operations. However, charge control is unable to reduce vibrations that limit the positioning bandwidth. Our main contribution is to ov...

Some hazards posed by the operation of hydraulic systems, connected with low-frequency vibrations and noise are presented. Special attention is focused on infrasounds. The sources of low-frequency vibrations and noise and ways of reducing them are indicated. An original solution ensuring the effective reduction of vibrations and noise in a wide frequency range, i.e., a wide-band damper of press...

The structure and properties of absorbed fluorine and chlorine atoms on GaAs surfaces are investigated. The energies of surface species' localized vibrations are determined. Our results show that localized As±Cl and Ga±Cl valence vibrations occur in the 40 and 50 meV regimes, respectively, while As±F and Ga±F vibrations are found in the 90 and 80 meV regimes, respectively. Comparisons are made ...

Everybody has sometimes experienced the vibrations generated by the performance of music. The floor or the seat place can vibrate because of the resonance or the structureborne sound stimulated by instruments. When these vibrations are correlated with airborne sound, they are additional information for us. The correlation between vibration and airborne sound might be important in implementing, ...

This article presents results of ground motion and magnet vibrations measurements at the Advanced Photon Source. The experiments were done over a wide frequency range (0.05-100 Hz) with the use of SM-3KV-type seismic probes from the Budker Institute of Nuclear Physics (Russia). Spectral power densities of vertical and horizontal motions of the APS hall floor and quadrupoles on regular supports ...

Vibrations of a nonlinear oscillator with an attached pendulum, excited by movement of its point of suspension, have been analysed in the paper. The derived differential equations of motion show that the system is strongly nonlinear and the motions of both subsystems, the pendulum and the oscillator, are strongly coupled by inertial terms, leading to the so-called autoparametric vibrations. It ...

in this study, the mf285 tractor engine vibrations resulting from the use of different combinations of biodiesel, bioethanol and diesel as fuel were studied. engine vibrations in three directions and three engine speeds: 1000, 1600 rpm 2000 and ten fuel level was measured. to investigate the influence of measured parameters on engine vibration of factorial design in a randomized complete block ...

The Compact LInear Collider (CLIC), presently under study at the European Organization for Nuclear Research (CERN), aims at colliding high-energy “nanobeams” at a luminosity of 10 cm−2s−1. Vibrations of the lattice elements, if not properly corrected, can result in a loss in performance by creating both unacceptable emittance growth in the linear accelerator and relative beam-beam offsets at th...

Terahertz VRT laser spectra of four ~H2O!2 intermolecular vibrations consisting of 362 transitions have been measured between 87 and 108 cm with ca. 2 MHz precision. The results differ both qualitatively and quantitatively from the predictions of dimer potentials tested. The spectra also reveal an ordering of the intermolecular vibrations which differs dramatically from that predicted by normal...

Vocal Vibrations is a new project by the Opera of the Future group at the MIT Media Lab that seeks to engage the public in thoughtful singing and vocalizing, while exploring the relationship between human physiology and the resonant vibrations of the voice. This paper describes the motivations, the technical implementation, and the experience design of the Vocal Vibrations public installation. ...