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This paper presents a new modulation strategy of the three-phase DC-DC Boost converter with high frequency isolation. This work has as its main objective to present a solution to deal with the forbidden region found in the study of the referred converter. The proposed modulation keeps the main characteristics of the original topology, which are: the voltage and current frequencies in the output filter are three times the switching frequency, input current ripple reduction, high frequency isolation, moreover, when the converter works within duty ratio up to 1/3, it makes it possible to precharge the output capacitor, reducing the start-up converter' currents. A theoretical analysis of the operating stages and the experimental results are presented to a prototype operating as a Flyback-Boost with switching frequency of 20 kHz, input voltage from 24 V to 120 V, output voltage from 52 V to 450 V and output power from 650 W to 2025 W.

Electrical/Electronic Engineering courses are often regarded as male courses. In this paper it is presented a study conducted in two Portuguese and two Brazilian high education institutions (six courses) where the goal was to analyze if gender affects students' perceptions and satisfaction regarding Electrical/Electronic Engineering courses. The analysis was based on 654 questionnaires rating 44 items (among the six groups: Teacher Involvement Perception, Student Interest, Student-Teacher interaction, Course organization and functioning, Infrastructures, and Overall satisfaction). The investigation was performed by year, from the first to the third year (1st cycle) and considering the six programs. Based on students' perceptions, some items showed differences that were significant, namely the ones regarding how teachers and students interact and how teachers challenge students.