seismic base isolation are devices that used to limit the human and material damage caused by an earthquake. this devices diffuse the energy induced at the time of the earthquake before being transferred to the structure.the base isolated structures when subjected to the near-fault eathquakes which contain long-period velocity pulses that may coincide with the period of base isolated structures...

SMA(Shape memory alloys) are unique materials with many excellent properties, such as wear resistance, corrosion high power/weight ratio and biocompatibility, damping, shape effect, super elasticity, etc. In civil engineering, scientists try to use the advantages of SMA by making it into different components they have already made some types that bracing, constrains RC columns, ring springs bas...

Nowadays it is commonly considered that high damping materials which have both the good mechanical properties as structural materials and the high damping capacity for vibration damping are the most direct vibration damping solution. In metals and alloys however, exhibiting simultaneously high damping capacity and good mechanical properties has been noted to be normally incompatible because the...

The paper deals with analysis of loading conditions on damping torque coefficient and synchronizing coefficient in SMIB system and design of Delta-Omega type of damping controller for damping of power oscillations in the system. Effect of variation of loading on synchronizing torque and damping torque coefficients has been investigated in detail. A new design approach for optimizing the paramet...

A new compact model of squeeze-film damping is developed based on the numerical solution of the Boltzmann kinetic equation. It provides a simple expression for the damping coefficient and the quality factor valid through the slip, transitional and free-molecular regimes. In this work, we have applied statistical analysis to the current model using the chi-squared test. The damping predictions a...

We determine the class of damped modes ỹ which are related to the common free damping modes y by supersymmetry. They are obtained by employing the factorization of Newton’s differential equation of motion for the free damped oscillator by means of the general solution of the corresponding Riccati equation together with Witten’s method of constructing the supersymmetric partner operator. This pr...

This paper investigates damping ratio in micro-beam resonators based on magneto-thermo-elasticity. A unique aspect of the present study is the effect of permanent magnetic field on the stiffness and thermo-elastic damping of the micro resonators. In our modeling the theory of thermo-elasticity with interacting of an externally applied permanent magnetic field is taken into account. Combined the...

In this paper, the Unified Power Flow Controller (UPFC) is enhanced with a Chaotic Particle Swarm Optimization (CPSO) Damping Controller in order to mitigate the Low Frequency Oscillations (LFO) in a Single Machine Infinite Bus (SMIB) power system. The designed damping controller is an optimized lead-lag controller, which extracts the speed deviation of the generator rotor and generates the out...

A discrete-time internal model principle based adaptive algorithm for identifying signals composed of a sum of exponentially damped sinusoids is presented. The time varying state variables of an internal model principle controller in a feedback loop can provide estimates of the exponentially damped sinusoidal signal parameters, the damping factor and the frequency. By using additional integral ...