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Biographies: Obituaries - Hideo Yamahsita Disclosure Number: IPCOM000129811D
Original Publication Date: 1994-Jun-30
Included in the Prior Art Database: 2005-Oct-07
Document File: 3 page(s) / 18K

Publishing Venue

Software Patent Institute

Related People

Sigera Takahashi: AUTHOR [+2]


Tokyo Engineering University

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Copyright ©; 1994 by the Institute of Electrical and Electronics Engineers, Inc. All rights reserved. Used with permission.

Biographies: Obituaries - Hideo Yamahsita

Sigera Takahashi

Tokyo Engineering University

Video Yamashita, one of Japan's earliest computing pioneers and founder of the Information Processing Society of Japan, died of heart failure at his home in Bunkyo-ku, Tokyo, on May 25, 1993. He was 94.

Born in Kanda, Tokyo, on May 21, 1899, Yamashita graduated from Tokyo Imperial University (now the University of Tokyo) with a BS degree in electrical engineering in 1923. Immediately after graduation he was appointed as a lecturer of the Faculty of Electrical Engineering at the university. In February 1938, he received a doctor's degree in engineering from the university and two months later became a professor there. Prior to this, Yamashita spent one and a half years in Europe and the US, mostly at MIT. His research interest changed after this to calculating machines, spurred by the need for them at the Bureau of Statistics of the Japanese government.

IBM punched-card machines were used in Japan for statistical calculations, and the demand for them had been rapidly increasing before 1940, when the US government banned exportation of these machines to Japan as war material. Yamashita and his colleagues, Katsuji Ono and Ryosaku Sato, conceived a calculating machine based upon binary logic, and launched its development with the use of electric relays in 1940. The shortage of parts and materials during the war hampered the development, and it was 1948 before they completed the machine using relays and counters released from military use.

The machine used 4,000 relays and 2,000 counters. It had 20 pairs of keyboards for data input and a dual arithmetic unit for statistical calculations. Input was made simultaneously through both keyboards of each pair. They had to accept identical input, and, if not, the input was discarded and had to be reentered. The arithmetic unit was shared by 20 pairs of inputs, and it added them up one by one. The dual results of each addition were compared with each other, and, if not identical, they were discarded and the addition was automatically repeated.

This machine was used by Chuohtoukei-sha, a not-for-profit organization, located in an annex building of the Ministry of Finance, Kasumigaseki, Tokyo, for statistical calculation services, which was the first attempt to provide computation services in Japan. It was eight years before the first commercial computation service bureau using a relay computer was offered in Tokyo by Fujitsu Ltd. NEC and Fujitsu, following Yamashita's design, produced one machine each in 1951. They were put into practical use at the Bureau of Statistics of the Japanese government and the Department of Statistics of the metropolitan government of Tokyo, respectively. It was a pity, when we look back, that Yam...