The Wave-based Finite Element Method or WFEM is applied to in-vacuo cylindrical shells to studystructure-borne wave interaction with bulkhead and keel-type plate attachments. The frequency rangeconsidered is from one to ten times the shell "ring" frequency. The goal is to better understand theshell-plate interaction, which plays an important role in the acoustic scattering and r...

Reduced order models employing the Lagrange and POD reduced basis methods in numerical approximation and feedback control of systems are presented and numerically tested. The system under consideration is a thin cylindrical shell with surface-mounted piezoceramic actua-tors. Donnell-Mushtari equations, modiied to include Kelvin-Voigt damping, are used to model the system dynamics. Basis functio...

A Hemispherical Resonator Gyro (HRG) is the Coriolis Vibratory Gyro (CVG) that measures rotation angle or angular velocity using Coriolis force acting the vibrating mass. A HRG can be used as a rate gyro or integrating gyro without structural modification by simply changing the control scheme. In this paper, differential control algorithms are designed for a 2-piece HRG. To design a precision c...

One source of structural vibration in a submarine is the fluctuating axial thrust force applied to the thrust block by the propeller shaft. This paper describes the initial stages of experimental work being undertaken to validate an existing mathematical model for the sound radiation from a submarine excited by this mechanism. A thin cylindrical shell 1500mm long and 400mm in diameter made of 2...

In this paper an optimization problem for a cylindrical shell under an applied dynamical loading is discussed. The aim is to look for an optimal thickness of a shell to minimize the deformation when the shell is subject to an external timedependent force together with an initial impact. The volume of the shell has to stay constant during optimization. A model for the deflection is derived and a...

Introduction. Technologies related to the use of low-temperature atmospheric plasmas are developing at a rapid pace. Creation new plasma sources for specific applications requires monitoring dynamic processes in such discharges with high time resolution. Electron concentration is one most important characteristics, which can be very low pressure plasma. However, methods currently available diag...

A compact dual-band antenna made of high dielectric constant substrate is studied. Embedding a higher dielectric cylindrical inside the substrate host cylindrical enhances the dual-band behaviour. The first part displays the characteristics of single CRDA as return loss, bandwidth and radiation pattern, then, the second part describes the aim of using an antenna, composed by the arrangement of ...

We explore an acoustic scattering cancellation shell for buoyant hollow cylinders submersed in a water background. A thin, low-shear, elastic coating is used to cancel the monopole scattering from an air-filled, neutrally buoyant steel shell for all frequencies where the wavelength is larger than the object diameter. By design, the uncoated shell also has an effective density close to the aqueo...

Vacuum expectation values of the field square and the energy-momentum tensor for the electromagnetic field are investigated for the geometry of a wedge with a coaxal cylindrical boundary. All boundaries are assumed to be perfectly conducting and both regions inside and outside the shell are considered. By using the generalized Abel-Plana formula, the vacuum expectation values are presented in t...

We report a new technique for the rapid fabrication of microstripe cylindrical and toroidal mirrors with a high ratio (>10) of the two principal radii of curvature (RoC(1)/RoC(2)), and demonstrate their effectiveness as mode-selecting resonator mirrors for high-power planar waveguide lasers. In this process, the larger radius of curvature (RoC(1)) is determined by the planar or cylindrical shap...