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A high voltage, high frequency transformer unit has been designed and built for powering the Cockcroft–Walton voltage multiplier to be used as part of a particle accelerator power supply at the Institute For Plasma Research, India, for the nuclear fusion research facility. A novel combination of high voltage (25 kV), high frequency (20 kHz), and high power (70 kV A) specifications makes its design distinctive and more challenging. The complete unit is composed of two 0.350/25 kV amorphous core transformers connected in center-tap configuration and immersed in an oil-filled tank. To facilitate an iterative design procedure, a spreadsheet method was utilized. The design involved a methodical approach for the core and winding selection, followed by the magnetic analysis and high voltage insulation layout through the finite element method. All the magnetic, electrical, and thermal parameters have been evaluated in detail, assuring a continuous stable operation having an efficiency of greater than 95%. Finally, the transformers were made, and preliminary experiments, including turns ratio, short-circuit, and dielectric tests, were carried out to verify the accuracy of the proposed design. The unit was also field tested under actual load conditions, and the test results were presented and corroborated with the design calculations. [ABSTRACT FROM AUTHOR]

The global incidence of very intense cyclones has increased in recent decades with climate projections signaling that this trend will intensify. To what degree can vulnerability to extreme weather events be mitigated by access to a rural livelihoods program, particularly with regard to the impacts on women? This paper addresses this question through a natural experiment arising from two independent but overlapping sources of variation: exposure to a devastating cyclone that occurred in the Bay of Bengal region of India and the staggered rollout of a rural livelihoods intervention. Comparisons from household surveys across communities more or less exposed to the storm before and after the introduction of the program reveal that the storm led to significant reductions in overall household expenditure, and that these reductions were indeed the largest for women, adding to the emerging evidence for the frequently-posed hypothesis that women bear the brunt of the effects of disasters on overall household consumption. Participation in the livelihoods program mitigated some of the reductions in household nonfood expenditure and women's consumption, but not on food expenditure. These results from a densely populated region whose topography makes it particularly vulnerable to storms can inform future policy approaches and aid in modeling the impact of these policies on the effects of climate change. [ABSTRACT FROM AUTHOR]