Draft:Takashi Isobe

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Takashi Isobe (Japanese: 磯部 孝, January 6, 1914 – October 7, 2001) was a Japanese physicist and engineer specializing in measurement and control engineering. He was a professor and later professor emeritus at the University of Tokyo. His research included underwater ballistics, flow measurement, correlation methods using random signals, and automatic control. He served twice as president of the Society of Instrument and Control Engineers (SICE) and was also a member of the science-writing group known as the Logergist.

Early life and education

Isobe was born on January 6, 1914, in Ueno-Sakuragi, Tokyo, as the eldest of six children. He spent his childhood in Ikebukuro and attended the elementary school attached to Toyoshima Normal School, followed by Tokyo Prefectural Sixth Middle School, now Tokyo Metropolitan Shinjuku High School.

In March 1930, after completing his fourth year of middle school, he entered the former Urawa Higher School. In 1933 he entered the Department of Physics at Tokyo Imperial University. He suffered from severe pneumonia while a student and delayed his progression by one year, graduating from the Department of Physics in March 1937.

After graduation, Isobe joined the Imperial Japanese Army Technical Headquarters as a civilian employee, initially working on ballistic calculations. From 1942 to 1944 he was dispatched by the Army Technical Headquarters to Tokyo Imperial University as a special graduate research student, where he studied underwater ballistics under Masaichi Majima.

Academic career

In 1945, Isobe became a lecturer in the First Faculty of Engineering at Tokyo Imperial University. Following the establishment of the Department of Measurement Engineering, he became an associate professor in 1946 and a professor in 1948.

From September 1959, he spent approximately one year as a visiting professor at Cornell University in the United States.

Isobe retired from the University of Tokyo in March 1974 and became professor emeritus. In April of that year, he became a professor in the Department of Photographic Engineering at Chiba University, where he worked on education and research in image measurement engineering. He retired from Chiba University in March 1979.

In 1979 he joined Chubu Institute of Technology as a professor. The institution was renamed Chubu University in 1984, and Isobe continued teaching and conducting research there for approximately ten years.

He died on October 7, 2001, at the age of 87.

Research

Underwater ballistics

While working at the Army Technical Headquarters, Isobe initially conducted ballistic calculations. Beginning in 1942, he pursued experimental studies of underwater ballistics at Tokyo Imperial University. His work examined phenomena including the ricochet of projectiles from the water surface and the motion of projectiles after entering water.

The University of Tokyo later described his work as having clarified in detail both ricochet at the water surface and projectile motion underwater, thereby opening a new field of research.

His results were later collected in the book Suichū dandō no kenkyū (水中弾道の研究, Studies in Underwater Ballistics), published by the University of Tokyo Press in 1975.

A Chiba University Library publication described the book as a study of the motion of high-speed projectiles entering water, a specialized problem in fluid mechanics.

Measurement engineering and flow measurement

After World War II, Isobe shifted the main focus of his research toward measurement engineering and its systematization. Together with Masaichi Majima, he edited the two-volume Keisokuhō gairon (計測法概論, Introduction to Measurement Methods), published in 1950–1951.

He also worked on industrial measurement, automatic control, and flow measurement. In 1956, he published a paper on problems in measurement and control technology in factories.

During the 1950s he developed a pulsating gas flowmeter. In 1958, Hiroo Hattori, Isobe, Takao Nomura, and Tositaka Hayasi published "Practical Tests of Pulsating Gas Flow Meter". The device had been developed into a commercial instrument and was tested under various experimental conditions.

During his stay at Cornell University, Isobe presented his work on pulsating flow measurement at a meeting of the Instrument Society of America (ISA, now the International Society of Automation). The following year he received an award from the society for this work.

Correlation methods and control

During the 1960s, Isobe studied correlation methods that used random signals to determine the characteristics of control systems and other systems. The University of Tokyo later credited him with establishing correlation techniques that contributed substantially to the subsequent development of measurement and control engineering.

In 1968, he edited Sōkan kansū oyobi supekutoru: sono sokutei to ōyō (相関函数およびスペクトル―その測定と応用, Correlation Functions and Spectra: Measurement and Applications), which summarized work in this field.

He also worked in control engineering and published an article on adaptive control in 1963.

That same year, Isobe supervised the Japanese translation of E. Mishkin and L. Braun Jr.'s Adaptive Control Systems, published by Corona Publishing as Tekiō seigyo-kei (適応制御系).

Industrial measurement

Isobe was also involved in the dissemination of measurement and automatic-control techniques in industry, particularly in the Japanese iron and steel industry.

In 1969, he gave a lecture titled "Recent Measurement and Control in the Iron and Steel Industry" at the sixth Nishiyama Memorial Technical Lecture of the Iron and Steel Institute of Japan. The lecture discussed measurement and computer control in processes including blast furnaces, sintering, converters, and rolling.

He continued to publish on the subject; a 1984 paper was titled "Progress of Measurement and Control in Iron and Steel Industry".

Spinning tops

In his later years, Isobe studied the dynamics of spinning tops and friction, including the mechanism by which a spinning top gradually rises and the behavior of the tippe top. He analyzed these phenomena by considering friction at the contact surface.

An essay titled "Koma wa naze okiagaru" (コマはなぜ起き上がる, "Why Does a Spinning Top Rise?") was included in the third volume of Shin Butsuri no sanpomichi (新 物理の散歩道, New Walks Through Physics).

In 1981, Isobe and his wife spent several months at Newcastle University at the invitation of Professor Leonard Maunder. According to a later biographical account, he considered submitting the results of his analysis of the tippe top to Nature, following Maunder's suggestion.

Professional activities

Isobe served as president of the Society of Instrument and Control Engineers in 1964 and again in 1975.

He was elected an honorary member of the society in 1978.

He also participated in committees concerned with measurement standards and chaired a specialist committee on measurement standards.

In 1996, he received the SICE Achievement Award.

Logergist

Isobe was one of the seven Japanese physicists in the group known as the Logergists, together with Hidetoshi Takahashi, Isao Imai, Koreo Kinoshita, Akiya Okawa, Masao Kondo, and Sōshin Chikazumi.

Beginning in 1959, the Logergists contributed monthly science essays to the magazine Shizen, examining everyday phenomena from the viewpoint of physics. Many of the essays were later collected in the Butsuri no sanpomichi (物理の散歩道, "Walks Through Physics") series.

The University of Tokyo's obituary for Isobe also noted his activities with the Logergists and the Butsuri no sanpomichi series.

Awards and honors

• 1944 – Noda Prize
• 1945 – Hattori Hokokai Award
• 1960 – Award from the Instrument Society of America
• 1981 – Medal with Blue Ribbon
• 1987 – Order of the Sacred Treasure, Second Class
• 1996 – Society of Instrument and Control Engineers Achievement Award

Selected books

• Masaichi Majima and Takashi Isobe, eds., Keisokuhō gairon (計測法概論), 2 vols., Corona Publishing, 1950–1951.
• E. Mishkin and L. Braun Jr., eds.; Takashi Isobe, supervising translator, Tekiō seigyo-kei (適応制御系), Corona Publishing, 1963.
• Masaichi Majima and Takashi Isobe, eds., Keisokuhō tsūron kōgi (計測法通論講義), University of Tokyo Press, 1967.
• Takashi Isobe, ed., Sōkan kansū oyobi supekutoru: sono sokutei to ōyō (相関函数およびスペクトル―その測定と応用), University of Tokyo Press, 1968.
• Masaichi Majima and Takashi Isobe, eds., Keisokuhō tsūron (計測法通論), University of Tokyo Press, 1974.
• Takashi Isobe, Suichū dandō no kenkyū (水中弾道の研究), University of Tokyo Press, 1975.

Selected papers

• Isobe, Takashi (1956). "工場における計測及び制御技術の諸問題" [Problems in measurement and control technology in factories]. Japan TAPPI Journal. 10 (7): 324–327. doi:10.2524/jtappij.10.324.
• Hattori, Hiroo; Isobe, Takashi; Nomura, Takao; Hayasi, Tositaka (1958). "Practical Tests of Pulsating Gas Flow Meter". Journal of the Instrument Technology, Japan. 8 (6): 342–349. doi:10.11499/sicejl1951.8.342.
• Isobe, Takashi (1963). "適応制御" [Adaptive control]. Journal of the Japan Society of Mechanical Engineers. 66 (528): 110–116. doi:10.1299/jsmemag.66.528_110.
• Isobe, Takashi (1984). "Progress of Measurement and Control in Iron and Steel Industry". Tetsu-to-Hagane. 70 (9): 1311–1312. doi:10.2355/tetsutohagane1955.70.9_1311.