This letter reports basic acoustic phenomena related to part-pedaling in the piano. With part-pedaling, the piano tone can be divided into three distinct time intervals: initial free vibration, damper-string interaction, and final free vibration. Varying the distance of the damper from the string, the acoustic signal and the damper acceleration were measured for several piano tones. During the ...

Semi active control systems are becoming increasingly popular because they offer reliability of passive systems combined with high performance and versatility of active control systems but with low power consumptions. As Magnetorheological (MR) fluids can produce good controllable damping force under application of magnetic field, MR damper can be used as effective element in semiactive vibrati...

In order to build high-precision and highefficient MR damper system model, a multi-domain unified modeling method was proposed. Firstly, based on the analysis of a MR damper semi-active suspension system model, various fields of MR, such as structure, magnetic field, control and mechanics, were studied to find the main influencing parameters. And then for the multi-domain coupling characteristi...

Some shape memory alloys like NiTi show noticeable high damping property inpseudoelastic range. Due to its unique characteristics, a NiTi alloy is commonly used forpassive damping applications, in which the energy may be dissipated by the conversion frommechanical to thermal energy. This study presents a shape memory alloy based micro-damper, which exploits the pseudoelasticity of NiTi wires fo...

Particle swarm optimization (PSO) technique has achieved a considerable success in solving nonlinear, nondifferentiable, multi-modal optimization problems. Currently, PSO is broadly applied in several scientific and engineering optimization applications. This paper introduces an identification of magnetorheological (MR) damper’s parameters using the PSO algorithm to introduce a more simple and ...

the performance of dual-layer multiple tuned mass dampers (dl-mtmd) with uniformly distributed natural frequencies is investigated. the dl-mtmd consists of one large tuned mass damper (l-tmd) and an arbitrary number of small tuned mass dampers (s-tmd). the primary structure is represented as a single degree-of-freedom system which corresponds to a specific vibration mode to be controlled in a r...

This article presents the development of a novel magnetorheological damper which has a self-sensing ability. In this study, a linear variable differential sensor, which was based on the electromagnetic induction mechanism, was integrated with a conventional magnetorheological damper. The working principle, configuration, and prototype of the displacement differential self-induced magnetorheolog...

Viaducts with roller bearings are subject to large displacement, which could lead the collapse of deck during earthquakes. This study attempts prevent displacements by installing steel stoppers at both sides bearings. The efficiency viscous damper stiffness on seismic performance curved viaducts combined use a spatial multipoint is evaluated. pounding phenomena exactly simulated, considering en...

This paper describes the results of an extensive study on the seismic behavior of a structure with damper and without damper under different earthquake acceleration frequency like Earthquake Altadena, Earthquake Lucerne and Earthquake New Hall. It is observed through nonlinear time history analysis that maximum displacement, maximum base shear and maximum acceleration can be effectively reduced...

Additional dampers are employed in order to decrease the dynamic response of structure against the earthquake and wind loading recently. In this study, two types of systems related to waste of inactive energy, i.e. frictional damper which is categorized in dampers dependent on movement and viscoelastic damper which is categorized in dampers dependent on velocity, in making steel structures resi...