Showing papers in "Journal of the Indian Institute of Science in 1996"
Journal Article•
TL;DR: In this article, a phase-modulated full-bridge converter (PMC) is presented, with a power density of nearly 5 W/inch3 (0.3 W/cm3 ).
Abstract: Hlgh power densities can be achieved in switched-mode power supplies, by switching at very high frequencies. The resonant transition converters have many desirable features at such high frequencies. One such converter, namely, the phase-modulated full-bridge converter (PMC) is presented in this paper. The basic principles of operation are briefly discussed. The various trade-offs involved in the design are explained. Experimental and simulation results. obtained on a 560 W/250 kHz PMC, with a power density of nearly 5 W/inch3 (0.3 W/cm3 ) are presented.
12 citations
Journal Article•
TL;DR: In this paper, an optical noncontact microtopographer based on discrete active triangulalion procedure which allows submicron range revolutions is described, where the topographic information is obtained from the horizontal shift incurred by the bright spot created by an oblique collimated light beam on a vertical surface.
Abstract: An optical noncontact microtopographer based on discrete active triangulalion procedure which allows submicron range revolutions is described. The system is based on a simple triangulation procedure where the topographic information is obtained from the horizontal shift incurred by the bright spot created by an oblique collimated light beam on a vertical surface. A lazer beam is focused on to a small, difraction-limited spot on the surface and is made to scan over the desired region. The bright spot is perpendicularly imaged on to a linescan camera and its position obtained from the data on the individual detectors that are activated above a certain controllable intensity threshold level. The shift in the corresponding horizontal spot on the reference plane is then computed. The distance between the surface and a reference plane at each sampled point is then easily calculated. A map of the surface topography can be built and Statistical surface characterization parameters calculated.
5 citations
Journal Article•
TL;DR: In this article, the authors describe the current interplay between theoretical and experimental high-pressure research with illustrations from their own studies and emphasis on future scope, and describe the similarities and differences in behaviour of materials under static and dynamic pressures.
Abstract: Studies on equation of state and phase transitions at high pressures have significantly contributed to our basic understanding of condensed matter physics. High-pressure data on materials also find important applications in applied sciences. The developments in first principle theories and experimental techniques are- listed. The similarities and differences in behaviour of materials under static and dynamic pressures are discussed. The article also describes the current interplay between theoretical and experimental high-pressure research with illustrations from our own studies and emphasis on future scope.
2 citations
Journal Article•
TL;DR: In this article, a laser pulse slicer was set up using avalanche transistor Murx-bank high-voltage nanosecond step pulse generators, which can provide single short-duration laser pulse variable from 4 m 10 to a few tens of nanosconds by simply changing a cable delay.
Abstract: A laser pulse slicer has been set up using avalanche transistor Murx-bank high-voltage nanosecond step pulse generators. This can provide single short-duration laser pulse- variable from 4 m 10 a few tens of nanoseconds by simply changing a cable delay. Optical configuration and electrical Circuits involved and the performance characterstics of the pulse slicer are described. A sliced laser pulse of 4 ns (FWHM) is obtained with an energy transmission of 14% from an input laser pulse of 28 os (FWHM). An intensity contrast ratio of 1200 is achieved between the peak and any prepulse
1 citations