Joh Kenzo was born in Osaka on January 29, 1904. He graduated from the Department of Mathematics, Faculty of Science of Kyoto Imperial University in 1928. And he became a lecturer of the Higher Technical School of Hamamatsu, and a lecturer of the Osaka Technological College (the college was incorporated into the Imperial University Osaka in 1933.) in 1929. He took over the lecture of mathematical Analysis which was the common lecture of the Faculty of Engineering and also he accumulated his shining achievements by the researches on the Schilicht function. He got the degree of Doctor of Science in 1941, and he became a professor of the Imperial University Osaka.
In 1939, he belonged the foundation of Department of Precision Machinery Engineering in the Department of Engineering and he began the lecture of Computing Machine which was a new lecture. From then during the World War II or before, he took great interests in the calculating instruments or mathematical machines. And he was performing the researches and collections of the analog devices such as a planimeter, an integrator, a harmonic analyzer, a differential analyzer, etc., and the digital devices such as a mechanical/electromotive table-top calculator, and a statistical machine (Punched Card System). He contributed and announced the results of his research on computing machines to the magazine of "Machine and Electricity" (Yokendo publishing company, Tokyo) as many papers that were published during two years from 1941. After that, he published the book of "Mathematical Instruments and Machines" (Zoshindo publishing company, Osaka) in 1947, although his manuscripts for the book were burned down repeatedly by the war fires.
As soon as the report on the ENIAC was presented in the "Newsweek" journal in 1946, Professor Joh began a study on an electronic computer in our country. He carried out the experiments on the counting devices of decimal system with vacuum tubes in 1949. Furthermore, he did the trial production and demonstration of the ENIAC type's arithmetic system which was consisted of 4 decimal digits with vacuum tubes in 1950. In parallel with under the execution of those studies and experiments, he was busily engaged in collecting for the acquisitions of literature on computer in the world which was difficult to get from overseas in the days when it was the postwar period. And he contributed to supply the informations on a computer to the researchers in domestic research organizations and universities. Later, Okazaki Bunji who manufactured the FUJIC was saying that I was often sent and given the literature on computers from Joh.
The book of "Digital and Analog Computers" (Kyoritsu Zensho, Kyoritsu publishing company, Tokyo) was published under joint authorship with Prof. Joh Kenzo and Associate Makinouchi Saburo (Osaka University) in June 1953. In those days, this was the only complete technical book on the electronic computer which was published in Japan. Furthermore he published serially the papers about programming method with the auxiliary title of "how to use an electronic computer" to the magazine of "Science and Machine" (Yokendo publishin company, Tokyo) in 1954. Moreover, to make preparations for the magnificent development of the computer in future he put into practice the lectures of the Numerical Analysis, Numerical Computing Method with Machine, and Probability & Statistics, and performed the studies of communication theory and information theory.
From 1950, he had started the research and trial production of a system of binary serial computer which consisted of vacuum tubes. He received the Government Science Research Grant of 800.000 yen for his research task in 1953 and he was continuing further into the trial production. However, the production of the computer did not look the completion at the end, because it became the current of times with what the transistorized computer did mainly concerned already when the scarce budget was managed and the completion was approaching at the last.
Since Joh was engaged in studies in computing machine, he was often talking as follows "A computer does not exist in temporarily". When he took an opportunity of meeting with people he spoke to them on the necessity of electronic computer as a very important matter for national policy. Moreover, he advocated about the need of industrial growth on a domestic computer. Also he did his best for growth of the domestic computers.
He presided over various societies for the studies on a computer in a variety of different disciplines in the Kansai regions. Moreover, he contributed to the establishment of the Information Processing Society of Japan, and to establishment of the Kansai branch of its society in 1963. He also did his best for developing both computer and information science in the academic world and the industrial world.
He retired Osaka University by the retirement age in 1967, and he was invited for a professor of the Faculty of Engineering of Kansai University till 1974. And he passed away on February 9, 1982.