Ryuji Koga

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BACKGROUND Although the onset mechanism of an olecranon stress fracture (OSF) due to a throwing disorder is believed to involve valgus extension overload, olecranon posteromedial impingement, or triceps traction force, this issue is still debated in the literature. PURPOSE To establish a classification system for the different types of OSFs to improve(More)
SUMMARY This paper explains a mechanism of common-mode generation on a printed circuit board with a narrow ground pattern. A transmission line has its value of degree of unbalance. At a connection point of two transmission lines having different degrees of unbalance, common mode voltage is generated proportional to the difference, and it drives common mode(More)
SUMMARY Placing a guard trace next to a signal line is the conventional technique for reducing the common-mode radiation from a printed circuit board. In this paper, the suppression of common-mode radiation from printed circuit boards having guard traces is estimated and evaluated using the imbalance difference model, which was proposed by the authors. To(More)
SUMMARY A guard trace placed near a signal line reduces common-mode radiation from a printed circuit board. The reduction effect is evaluated by the imbalance difference model, which was proposed by the authors , when the guard trace has exactly the same potential as the return plane. However, depending on interval of ground connection of the guard trace,(More)
Some recent results from research conducted in the EMC group at Okayama Universiry are reviewed A scheme for power-bus modeling with an analytical method is introduced. A linear macro-model for ICdLSIs. called the LECCS model, has been developed for EM and EMS simulation. This model has a very simple structure and is suficiently accurate. Combining the(More)
SUMMARY We propose a novel technique of matching at both ends of the guard trace to suppress resonance. This approach is derived from the viewpoint that the guard trace acts as a transmission line. We examined that matched termination suppresses guard-trace resonance through simulating a circuit and measuring radiation. We found from these results that the(More)
Symposium in Japan, because they have been held every five years since 1984. Number of attendee was 409 from 21 countries, though the number was less than had been expected due to the Lehman Shock which prohibited financial support of attendees by their farms. Still many traveled with their own expense and enthusiastic discussions were held. Next conference(More)