Power oscillation damping controller is designed in linearized model with heuristic optimization techniques. Selection of the objective function is very crucial for damping controller design by optimization algorithms. In this research, comparative analysis has been carried out to evaluate the effectiveness of popular objective functions used in power system oscillation damping. Two-stage lead-...

Acoustic Black Holes (ABH), a new method of passive vibration damping, have received much interest recently due to their lightweight and economically efficient properties. This paper aims to establish the optimal shape of the damping layer treated on ABH under harmonic loading. Firstly, a validation of numerical scheme that is used throughout this paper is carried out. A good agreement of the n...

Accurate evaluation of damping ratios involving soilstructure interaction (SSI) effects is the prerequisite for seismic design of in-situ buildings. This study proposes a combined approach to identify damping ratios of SSI systems based on ambient excitation technique. The proposed approach is illustrated with main test process, sampling principle and algorithm steps through an engineering exam...

This note deals with three aspects of nonproportional damping in linear damped vibrating systems in which the stiffness and damping matrices are not restricted to being symmetric and positive definite. First, we give results on approximating a general damping matrix by one that commutes with the stiffness matrix when the stiffness matrix is a general diagonalizable matrix, and the damping and s...

There are in the literature several theories to explain the mass loss in stellar winds. In particular, for late-type stars, some authors have proposed a wind model driven by an outward-directed flux of damped Alfvén waves. The winds of these stars present great amounts of dust particles that, if charged, can give rise to new wave modes or modify the pre-existing ones. In this work, we study how...

Particle damping is a technique to reduce the structural vibrations by means of placing small metallic particles inside a cavity that is attached to the structure at location of high vibration amplitudes. In this paper, we have presented an analytical model to simulate the particle damping of two dimensional transient vibrations in structure operating under high centrifugal loads. The simulatio...

PURPOSE When performing coronary angiography (CAG), diagnostic catheter intubation to the ostium can cause damping of the pressure tracing. The aim of this study was to determine the predictors of atherosclerotic ostial stenosis in patients showing pressure damping during CAG. MATERIALS AND METHODS In total, 2926 patients who underwent diagnostic CAG were screened in this study. Pressure damp...

Design of Linear Collider projects are in progress as a world wide collaboration. There are two possibility for the linear collider scheme: one is normal conducting cavity with X/C band power source, and another is superconducting cavity with L band power source. A positron damping ring storages positron beam during several damping time and extracts the beam with a very low emittance to a main ...

Enhancement of stability of the power system has been achieved by the application of Unified power flow controller (UPFC) device with an additional supplementary controller. This supplementary damping controller can be installed on any control channel of the UPFC inputs to implement the task of power oscillation damping (POD) controller. We have presented a comprehensive assessment and performe...