Nobuyuki Tokura

Loop prevention for IEEE1394-1995 and IEEE1394a-2000 networks

A method that avoids the logical loop topology to realize reliable IEEE 1394 networks is proposed. The restoration time is theoretically calculated and experimentally confirmed to be around 1.4 msec for a network that includes 3 loops; we assume the existence of the port disable function of IEEE 1394a-2000. Theoretical reliability of the method is estimated.

Loop prevention for IEEE 1394 network

The loop prevention method, which avoids misconnection (loop connection) and realizes a reliable network is proposed. The port disable function of P1394a is applied to the IEEE 1394 network. The restoration time is experimentally obtained to be around 1.4 msec for a network including 3 loops.

Lecturer Position Detection for Distribution System Using High Resolution Partial Images

Most distance learning or teaching systems use just regular television equipment, so the receiver is limited to passively watching the incoming low-resolution video stream. We have created a high-resolution image transfer system that creates a virtual copy of the senders environment, captured by multiple high-resolution still cameras, within the receivers computer. The receiver can peruse the virtual copy and zoom in to read what the lecturer has written on the board whenever desired. This paper shows how to reduce the transmission bandwidth required; the system periodically updates the images held in the receivers computer when necessary by sending only the images in which a significant change is detected and that show the lecturers most recent position. A simple method of detecting the lecturers position accurately is introduced and we discuss the impact of sound localization on service acceptance.