In this paper we consider a plate equation with internal feedback and viscoelastic damping localized on a part of the boundary. Without imposing restrictive assumptions on the time-dependent frictional damping, we establish an explicit and general decay rate result that allows a wider class of relaxation functions and generalizes previous results existing in the literature.

Control systems for shakers are necessary to remove both shaker dynamics as well as coupling effects between the shaker and the structure under test. Little attention has been given to shaker control for nonlinear structures. This paper presents the design, implementation and results of a shaker controller for a horizontal, cantilevered beam subjected to a non-uniform magnetic field. The object...

The aim of this short note is twofold. First, we give a sketch of the proof of a recent result proved by the authors in the paper [7] concerning existence and uniqueness of renormalized solutions of continuity equations with unbounded damping coe cient. Second, we show how the ideas in [7] can be used to provide an alternative proof of the result in [6, 9, 12], where the usual requirement of bo...

The interaction of work fluid mechanics with that of the rotary system itself, basically composed of axes, bearings and rotors, is performed by inserting equivalent dynamic coefficients in the mathematical model of the rotor, the latter being obtained by the finite element method. In this paper, the dynamic coefficients of inertia, stiffness and damping of the flat seals analyzed here are evalu...

The dynamic behavior of offshore wind turbines (OWTs) must be designed considering stochastic load amplitudes and frequencies from waves mechanical loads associated with the spinning rotor during power production. proximity OWT natural frequency to excitation combined low damping necessitates a thorough analysis sources damping; these damping, least is known about contributions soil-structure i...

External dampers and cross-ties are commonly used to control vibrations of stay cables on cable-stayed bridges. While dampers contribute directly to the structural damping of the attached cables, cross-ties mainly help to increase the stiffness of the connected cable system. The idea of incorporating cross-ties with dampers has also been attempted in a few recent applications to benefit from th...

A damping device, consisting of an annular tail-pipe, has been developed. It is applicable in situations wherein acoustic damping is required in combination with low flow resistance. Examples are ventilation systems, turbo-engines, intake and exhaust systems for internal combustion engines. The device consists of a central tube surrounded by a narrow slit. The central tube has an acoustic mass ...