The possibility of employing internal wall as mass absorber in rectangular water storage tanks subjected to harmonic ground motion excitation is investigated in this paper. Internal walls are used in these tanks usually for service performance purposes, which could be used as mass absorber to control seismic demand on tank's exterior walls. Derivation of the response of the coupled system inclu...

A completely general method of analysis for three-dimensional raked piles under harmonic excitation is discussed. The piles have been represented by a three-dimensional frame structure and the soil has been represented by a boundary element discretization scheme. A computer program has been written which carries out this analysis and produces a group stiffness matrix that can be included as a f...

We present experimental results of second harmonic generation using a waveguide of PUSC deposited on a silver diffraction grating. The reflected second harmonic signal is enhanced at the angles of resonant excitation of the guided modes or of the surface plasmon. At these angles, we observe unexpected minima in the second harmonic signal, when the second harmonic frequency is situated within th...

Improved visualization of blood vessels by ultrasound contrast agents requires insonation that is adapted to the dynamics of the contrast agent bubbles. To evaluate the interrelation between parameters of the exciting pressure field and the contrast agent, the dynamics of air filled microbubbles immersed in water are examined by numerical evaluation of the Rayleigh-Plesset equation. Unsymmetric...

Coded excitation methods offer the potential for improving the SNR without increasing the peak transmitted power and without sacrificing resolution. Our study examines the potential application of coded waveforms, specifically FM chirps, in harmonic imaging. Such a system, in which nonlinear echoes from tissue are used to form the image, requires the extraction and compression of the second har...

We present the first study of nonlinear optical third-harmonic generation (THG) in the strongly correlated charge-transfer insulator Sr(2)CuO(2)Cl(2). For fundamental excitation in the near infrared, the THG spectrum reveals a strongly resonant response for photon energies near 0.7 eV. Polarization analysis reveals this novel resonance to be only partially accounted for by three-photon excitati...

We resolve an open question about the origin of the giant enhancement in the high-harmonic generation spectrum of atomic xenon around 100 eV. By solving the many-body time-dependent Schrödinger equation with all 4d, 5s, and 5p orbitals active, we truly demonstrate the enhancement results from the collective many-body excitation induced by the returning photoelectron via two-body interchannel in...

This paper introduces a framework for parametric speech modeling that can be used in various speech applications such as text-to-speech synthesis, voice conversion etc. In order to reduce impact of pitch variations the harmonic analysis is done in the warped time scale that is aligned with instantaneous pitch values. It is assumed that each harmonic has its own periodic excitation source that e...