Common-Mode Noise Cancellation in Switching-Mode Power Supplies Using an Equipotential Transformer Modeling Technique

Electromagnetic interference (EMI) is a significant challenge in the design of high-efficiency switching-mode power supplies due to the presence of common-mode (CM) noise. In many power-supply designs, a variety of noise suppression schemes must be implemented in order to meet EMI requirements. Most of these schemes create power loss that lead to efficiency and thermal issues. In this paper, a transformer construction technique is proposed that effectively reduces the CM noise current injecting across the isolated primary and secondary windings. This technique is based on the zero equipotential line theory. A transformer design with the proposed CM noise cancellation technique can achieve high conversion efficiency as well as substantial CM noise rejection.published_or_final_versio

Development of an autonomous character in Karate Kumite

Virtual Reality (VR) has become common practice in the field of sports, but autonomous virtual environment (VE) systems, especially in fast reacting sports, are rare. The current study demonstrates the development of an autonomous character (AC) in karate kumite, which performs attacks against a freely moving, real athlete. The development of the AC consists of four steps: selection of relevant karate techniques, development of a decision system, creation of an animated model of the AC, and the evaluation. A Cave Automatic Virtual Environment (CAVE) and a Head Mounted Display (HMD) were chosen for the VE. The evaluation of the AC in the VEs was conducted by expert interviews (n = 6). The results reveal a feeling of comfort for all athletes in VR which underpins a high degree of realism in the VEs. Moreover, the HMDs are seen as more suitable than CAVEs for presenting a karate specific environment. Based on these results the developed AC seems applicable for anticipation research and training in karate kumite. The discussion includes further possible improvements for the AC as well as future directions for further investigations and training programs using the AC. Moreover, the procedure of the AC’s creation can be transferred to other sports