Useful approximation formulae for radiation impedance are given for the reflection coefficients of both infinitely flanged and unflanged rigid-walled cylindrical ducts. The expressions guarantee that simple but necessary physical and mathematical principles are met, like hermitian symmetry for the reflection coefficient (identical behaviour of positive and negative frequencies) and causality fo...

− In this paper a simple algorithm to detect an emergency vehicle’s siren using the linear prediction is presented. By measuring the means and variances of the reflection coefficients in a preselected number of successive frames, automatic detection of emergency vehicle’s siren is possible. It has been shown that only two coefficients are enough for successful detection. Due to the simplicity o...

We propose a new method for classification of photometric factors, such as diffuse reflection, specular reflection, attached shadow, and cast shadow. For analyzing real images, we utilize the photometric linearization method which was originally proposed for image synthesis. First, we show that each pixel can be photometrically classified by the simple comparison of the pixel intensity. Our cla...

We present numerical procedures for analyzing the properties of periodic structures and associated couplers based upon time domain simulation. Simple post processing procedures are given for determining Brillouin diagrams and complex field distributions of the traveling wave solutions, and the reflection coefficient of the traveling waves by the input and output. The availability of the reflect...

For well-generated complex reflection groups, Chapuy and Stump gave a simple product for a generating function counting reflection factorizations of a Coxeter element by their length. This is refined here to record the number of reflections used from each orbit of hyperplanes. The proof is case-by-case via the classification of well-generated groups. It implies a new expression for the Coxeter ...

 In view of the fact that pre-service teachers’ critical reflection through evaluating teaching activity of their peers is an important part of practicum activity, the current study aimed to analyze the recall and reflection journals written by pre-service teachers to identify and evaluate the discoursal features of their journals. To this end, a total of 272 recall and reflection journals writ...

We make a complete pole analysis of the reflection factors of the boundary scaling Lee-Yang model. In the process we uncover a number of previously unremarked mechanisms for the generation of simple poles in boundary reflection factors, which have implications for attempts to close the boundary bootstrap in more general models. We also explain how different boundary conditions can sometimes sha...

Submitted for the MAR08 Meeting of The American Physical Society Single and double reflection Michelson atom interferometers in a weakly-confining magnetic trap RUDRA KAFLE, JAMES STICKNEY, WPI, DANA ANDERSON, JILA, University of Colorado and NIST, ALEX ZOZULYA, WPI — We analyze the operation of a BEC based atom interferometer, where the atoms are held in a weakly-confining magnetic trap and ma...

Accurate surface reflection models derived from existing natural scenes can be used for a variety of tasks. This paper presents a machine vision approach for determining such models. We investigate the use of simplistic models of reflection and daylight illumination to determine surface reflection properties. We attempt to determine the gloss factor of both an individual surface and a multi-fac...

1. The reflection by a crystal of X-radiation characteristic of the atoms in the crystal itself, which Dr. G. L. Clark and the writer discovered (these PROCEEDINGS, May, 1922 and April, 1923), does not appear to be explainable in a simple manner by the theoryof interference of waves. This note describes an attempt to formulate a theory of the reflection of X-rays by crystals, based on quantum i...