Recent advances in the development of a wave travel time methodology for earthquake damage detection in buildings, for use in rapid assessment of structural health following an earthquake, are reviewed. Its main advantages over the modal methods are the insensitivity to the effects of soil-structure interaction, local nature, and robustness when applied to real structures and strong earthquake ...

Abstract An elastic wave in a physical beam naturally possesses many modes, such as flexural, longitudinal, and torsional. Therefore, suppression of all possible vibration modes has been rarely achieved beam-shaped periodic systems, especially at low frequencies. Here we present low-frequency complete bandgap mechanism by overlapping the flexural with longitudinal-torsional bandgap. To strength...

We suggest a mechanism for enhancing magnetic activity in tidally interacting binaries. We suppose that the deviation of the primary star from spherical symmetry due to the tidal influence of the companion leads to stellar pulsation in its fundamental mode. It is shown that stellar radial pulsation amplifies torsional Alfvén waves in a dipole-like magnetic field, buried in the interior, accordi...

PURPOSE To observe torsional movements of the eye in refractive surgery, and their possible consequences in the surgery outcome. METHODS In a prospective study, 49 eyes of 40 patients were submitted to surgical correction of astigmatism, by the LASIK technique. Patients were divided in two groups based on the cylindric power. Group A from -0.25 to -2.00D; group B from -2.25 to -6.00D. The occ...

We consider the regime in which the bands of the torsional acoustic (TA) and the hydrogen-bond-stretch (HBS) modes of the DNA interpenetrate each other. Within the framework of a model that accommodates the structure of the double helix, we find the three-wave interaction between the TA-and the HBS-modes, and show that microwave radiation could bring about torsional vibrations that could serve ...

The propagation of elastic waves along composite wire rope is considered. The rope is modeled as co-axial layers of cylindrically anisotropic material. Simple kinematical assumptions lead to a ‘‘rod theory’’ for the wire rope, consisting of three coupled onedimensional wave equations. Solutions of these equations are found. Results for a particular aluminum conductor steel reinforced (ACSR) con...

The lower frequency rQ 2-branch of the torsional split rotational spectrum of H OO H has been recorded for the first time near 1.05 THz with Doppler limited resolution employing a Backward Wave Oscillator as the radiation source. The position of the Q-branch lines can be predicted very closely from a set o f effective rotational constants derived individually for the two torsionally split level...

We characterize the linear viscoelastic shear properties of an aqueous wormlike micellar solution using diffusing wave spectroscopy (DWS) based tracer microrheology as well as various mechanical techniques such as rotational rheometry, oscillatory squeeze flow, and torsional resonance oscillation covering the frequency range from 10(-1) to 10(6) rad/s. Since DWS as well as mechanical oscillator...

In cylindrical shells, the lowest natural frequency is not necessarily associated with the lowest wave index. In fact, the natural frequencies do not fall in ascending order of the wave index either. Solution of the vibration problem of cylindrical shells also indicates repeated natural frequencies. These modes are referred to as double peak frequencies. Mode shapes associated with each one of ...