Design, assembly process and preparation of windings for large power transformers are complex procedures. It is very important to recognize resonant frequencies the during design phase in order avoid increase vibrations, stresses or noise levels normal operation transformer. Increased vibrations can occur when frequency excitation close natural system. In that case amplitudes will increase, the...

The objective of this paper is to present comprehensive lists accurate natural frequencies isotropic thin rectangular plates. For purpose, a simple yet very analytical approach described study the free vibration In numerical computations, convergence and comparison studies are conducted check accuracy solution demonstrate improvement solutions in results. Twenty-one tables then provided give lo...

The equivalent circuit representation of the dipole modes of the SLAC damped detuned structure (DDS) which is being fabricated at SLAC [1] has been analyzed by three different methods. The first two [1] are based upon a modal analysis: in the first, damped modes are found by a first order perturbation in the cell to damping manifold coupling strength; while in the second, preferred when the cou...

The rapid reorganization of the actin cytoskeleton in response to external stimuli is an essential property of many motile eukaryotic cells. Here, we report evidence that the actin machinery of chemotactic Dictyostelium cells operates close to an oscillatory instability. When averaging the actin response of many cells to a short pulse of the chemoattractant cAMP, we observed a transient accumul...

In this study, nonlinear vibration of axially moving strings in thermal environment is investigated. The vibration haracteristics of the system such as natural frequencies, time domain response and stability states are studied at different temperatures. The velocity of the axial movement is assumed to be constant with minor harmonic variations. It is presumed that the system and the environment...

On a range of elastic and damped surfaces, human hoppers and runners adjust leg mechanics to maintain similar spring-like mechanics of the leg and surface combination. In a previous study of adaptations to damped surfaces, we changed surface damping and stiffness simultaneously to maintain constant surface compression. The current study investigated whether hoppers maintain spring-like mechanic...

This paper presents an analytical and computational method to describe natural frequencies of a spherical bubble residing near solid sphere arbitrary size in otherwise unbounded fluid. Under low capillary Reynolds number limits, the relevant hydrodynamic fields are converted into time-invariant but frequency-dependent quantities by temporal Fourier transform. Then, spatial variations velocity p...