String inspired models with millimeter scale extra dimensions provide a natural way to understand an ultralight sterile neutrino needed for a simultaneous explanation of the solar, atmospheric and LSND neutrino oscillation results. The sterile neutrino is the bulk neutrino (νB) postulated to exist in these models, and it becomes ultralight in theories that prevent the appearance of its direct m...

We examine the effects of photon-axion mixing on the CMB. We show that if there are very underdense regions between us and the last scattering surface which contain coherent magnetic fields (whose strength can be orders of magnitude weaker than the current bounds), then photon-axion mixing can induce observable deviations in the CMB spectrum. Specifically, we show that the mixing can give rise ...

This paper presents the analysin ,design and implementation of a high voltage ratio topology of DC-DC converter. The DC-DC converter has high voltage ratio with reduced input current, output voltage and output current ripple, and also reduces the voltage and current rating of power electronics components and compared with conventional boost converter. The voltage stress on the switches are  red...

although in recent two decades, the concept of dielectric barrier discharges (dbds) have been developed in ozone production well, air pollution control, plasma screens and control of chemical, and biological and medical processes, employment of this concept for high voltage applications to improve insulation performance as an alternative to the pressurized gas-insulated systems (gis) utilizing ...

electric power industry have always try to provide reliable electricity to customers and at the same time decrease system costs. high voltage circuit-breakers are an essential part of the power network. this study has developed a maintenance and replacement scheduling model for high voltage circuit- breakers that minimize maintenance costs while maintaining the acceptable reliability. this mode...