We have performed laser-Doppler vibrometry measurements of the vibration of a double-paddle oscillator. Seven modes with principally out-of-plane motion have been identified. Their resonance frequencies and mode shapes are in excellent agreement with three-dimensional finite element simulations. We have found that the second antisymmetric torsional mode has exceptionally good vibration isolatio...

This document presents a technique based on the JBIG algorithm for binary shape coding in both lossless and lossy modes. Because it is applied directly to the bitmap representing the shape information, it bypasses the overhead in computation of an intermediate contour representation and its associated conversions. This leads to a simpler algorithm which is more suitable for a larger class of sh...

We evaluate the shape and chirp of nanosecond pulses from a fiber laser passively mode locked with a nanotube-based saturable absorber by using a synchronously scanning streak camera and a monochromator to directly measure the pulse spectrogram. We show that the stable sech(2) output pulse possesses a predominantly linear chirp, with a residual quartic phase and low noise. Comparison with analy...

For high current applications, it is desirable for the cavity shape to have a low longitudinal loss factor and to have a high beam-breakup threshold current. This paper briefly describes three different cavities designed for this purpose: a six-cell elliptical cavity for particles traveling at the speed of light, a two-cell elliptical cavity for subluminal particle speeds, and a single cell cav...

Pupil shape in vertebrates ranges from circular to vertical, with multiple phylogenetic shifts in this trait. Our analyses challenge the widely held view that the vertical pupil evolved as an adaptation to enhance night vision. On functional grounds, a variable-aperture vertical pupil (i) allows a nocturnal species to have a sensitive retina for night vision but avoid dazzle by day by adjusting...

The Modal Assurance Criterion (MAC) has been used for numerous years as a measure of correlation between test and analytical mode shapes. The fact that the MAC considers only mode shapes usually means that a separate frequency comparison must be used in conjunction with the MAC values to determine the correlated mode pairs. The mode shape correlation has generally been displayed as the MAC matr...

The detailed temperature dependence of the infrared-active mode in Fe1.03Te (TN 68 K) and Fe1.13Te (TN 56 K) has been examined, and the position, width, strength, and asymmetry parameter have been determined using an asymmetric Fano profile superimposed on an electronic background. In both materials the frequency of the mode increases as the temperature is reduced; however, there is also a slig...

In vision, colour constancy allows the evaluation of the colour of objects independent of the spectral composition of a light source. In the auditory system, comparable mechanisms have been described that allows the evaluation of the spectral shape of sounds independent of the spectral composition of ambient background sounds. For echolocating bats, the evaluation of spectral shape is vitally i...

A variety of techniques in machine vision involve representation of objects by using their shape skeleton. Many algorithms have been proposed to date for obtaining the skeletal shape of digital images. The noise models predominantly used in these techniques are restricted to boundary noise. In particular, instances of noise occurring inside object regions and causing their non-contiguity are pr...

in the present paper, resonant frequencies and modes of a three-atom photonic molecule and a photonic crystal placed within a cavity are numerically calculated. first, governing formulation in transverse electric field mode (te) is obtained using maxwell equations. then, an algorithm based on a finite difference scheme and matrix algebra is presented. the algorithm is then implemented in a comp...