A fast-Fourier-transform method of topography and interferometry is proposed. By computer processing of a noncontour type of fringe pattern, automatic discrimination is achieved between elevation and depression of the object or wave-front form, which has not been possible by the fringe-contour-generation techniques. The method has advantages over moire topography and conventional fringe-contour interferometry in both accuracy and sensitivity. Unlike fringe-scanning techniques, the method is easy to apply because it uses no moving components.

Fourier-transform method of fringe-pattern analysis for computer-based topography and interferometry

Digital processing of speech signals

Computer and Robot Vision Vol. 1, by R.M. Haralick and Linda G. Shapiro, Addison-Wesley, 1992, ISBN 0-201-10887-1.

Computer and Robot Vision

Applied Numerical Analysis. By C.F. Gerald. Pp. xii, 340. £3·60. 1970. (Addison-Wesley.)

An electrosurgical generator has an output power control system that causes the impedance of tissue to rise and fall in a cyclic pattern until the tissue is desiccated. The advantage of the power control system is that thermal spread and charring are reduced. In addition, the power control system offers improved performance for electrosurgical vessel sealing and tissue welding. The output power is applied cyclically by a control system with tissue impedance feedback. The impedance of the tissue follows the cyclic pattern of the output power several times, depending on the state of the tissue, until the tissue becomes fully desiccated. High power is applied to cause the tissue to reach a high impedance, and then the power is reduced to allow the impedance to fall. Thermal energy is allowed to dissipate during the low power cycle. The control system is adaptive to tissue in the sense that output power is modulated in response to the impedance of the tissue.

Electrosurgical generator with adaptive power control

A Tabu-gradient search algorithm is presented for improving the performance of FBG sensors in an intensity and wavelength-division multiplexed sensing system. Simulation results demonstrated that by using this technique the Bragg wavelengths of the FBG sensors can be accurately and quickly detect even when the original spectrums of FBG sensors can not be pre-determined.

/pdf/improving-the-performance-of-iwdm-fbg-sensing-system-using-1vtww8zun7.pdf

Improving the Performance of IWDM FBG Sensing System Using Tabu-Gradient Search Algorithm

The performance of structured light profilometers is significantly hindered by the generation of distorted sinusoid fringe images, particularly, for multi-channel applications. In this paper we investigate the application of neural network fringe calibration for the multi-channel approach. We analytically review the nature of the major error sources associated with the multi-channel approach and propose a fringe calibration technique with emphasis on minimal photometric calibration. The performance of the calibration technique is gauged through both simulation and experimentation.

/pdf/multi-channel-digital-fringe-calibration-for-structured-4uq1zi2mgz.pdf

Multi-channel Digital Fringe Calibration for Structured Light Profilometers using Neural Networks

A time-domain interpolation approach for DFT harmonic analysis

ICT education: challenge of accommodating change

A novel parallel adaptive line enhancer (PALE) model structure based on an infinite impulse response (IIR) bandpass filter is proposed The purpose of the given PALE model structure is to estimate and retrieve multiple frequencies buried in noise. The proposed model structure provides some unique features when compared with conventional approaches. First, the given approach works for the situation where there is no a priori information regarding the location of the various sinusoidal frequencies. Under these circumstances conventional PALEs are problematic since the individual parallel modules tend to converge to the same frequencies or may be trapped in the local minima. Second, the error surfaces of successive modules are improved by the module which has just converged to a particular frequency. In this respect, the proposed PALE model structure can be regarded as a hybrid combination of conventional parallel and cascaded configurations. Consequently, it utilizes the best features of each config...

Joe F. Chicharo

Papers

Improving the Performance of IWDM FBG Sensing System Using Tabu-Gradient Search Algorithm

Multi-channel Digital Fringe Calibration for Structured Light Profilometers using Neural Networks

A time-domain interpolation approach for DFT harmonic analysis

ICT education: challenge of accommodating change

A novel parallel IIR adaptive line enhancer model structure