identification of damping parameter is usually more complicated and unreliable comparing to mass or stiffness identification in structural dynamics. there are many factors such as intermolecular friction, coulomb friction and viscous damping affecting the damping mechanisms in a structure. therefore it is difficult, and in some cases impossible, to describe the details of damping mechanisms by ...

A method is suggested to reduce structural response to earthquakes using viscous dampers with their effect magnified by mechanical levers (lever arms). The lever arms are used to magnify the drift and the drift velocities transferred from the structure to the dampers thus producing in larger energy dissipation. An optimal design procedure based on the LQR technique is proposed in this study to ...

This paper presents a novel approach for tuning unified power flow controller (UPFC) based damping controller in order to enhance the damping of power system low frequency oscillations. The design problem of damping controller is formulated as an optimization problem according to the eigenvalue-based objective function which is solved using iteration particle swarm optimization (IPSO). The effe...

this paper presents a new damping controller design based on fuzzy wavelet neural network (fwnn) to damp the multi-machine power system low frequency oscillations. the error between the desired system output and the output of control object is directly utilized to tune the network parameters. the orthogonal least square (ols) algorithm is used to purify the wavelets for each rule and determine ...

This paper presents an optimal design of a Static Var Compensator (SVC) for damping improvement of a Single Machine Infinite Bus (SMIB) system. In this study, SVC is installed to improve the angle stability of a synchronous generator. A new computational intelligence approach using Mutated Particle Swarm Optimization (MPSO) technique is implemented. The study involves the optimization of the pr...

Due to the deregulation in the electrical market, difficulties in building new transmission lines, and the continuous increase in power demand the maintenance of power system stability becomes difficult and a very challenging problem. In large, interconnected power system damping is often reduced, leading to lightly damped electromechanical modes of low frequency oscillations (0.1~0.6Hz). In th...

Problem statement: Static Var Compensators (SVC) devices are used to improve voltage and reactive power conditions in AC systems. An additional task of SVC is to increase transmission capacity as result of power oscillation damping. The effectiveness of this controller depends on its optimal location and proper signal selection in the power system network. A residue factor had been proposed to ...

Collective decoherence is possible if the departure between quantum bits is smaller than the effective wave length of the noise field. Collectivity in the decoherence helps us to devise more efficient quantum codes. We present a class of optimal quantum codes for preventing collective amplitude damping to a reservoir at zero temperature. It is shown that two qubits are enough to protect one bit...

We start with a short introduction to the roof concept. An elementary discussion of phase-damping channels shows the role of anti-linear operators in representing their concurrences. A general expression for some concurrences is derived. We apply it to 1-qubit channels of length two, getting the induced foliations of the state space, the optimal decompositions, and the entropy of a state with r...