Yasui Hiroshi was born in Osaka on June 7, 1927. He was employed as a research assistant at the Kansai branch office of the Army Technical Research Institute of Tama in 1944. He was engaged in the research and trial production of the guidance control system of the rocket airplane named "SHUUSUI" at the institute. In the midst of the research, he met the end of the World War II. In 1945, he established the Horiba Radio Laboratory with his friends in Kyoto.

In 1948, since he was appreciated Joh Kenzo of the Department of Precision Machinery, Faculty of Engineering of Osaka University, he became an assistant of experiments on computer, and then was employed in Osaka University. From at that time he began his studies on an electronic computer under the leadership of Joh in the Joh's computing machine laboratory. As the results of studying a calculation that used vacuum tubes, he was able to demonstrate and exhibit the experiments of electronic computing which were the calculations of 1 digit of decimal number with some control units in 1949. This demonstration was the event under the lecture about an electronic computer which was performed by Prof. Joh at the meeting for the Society of Kansai Statistical Machine Study, it was still PCS period at that time. Although the staff of Joh's laboratory and he carried out the trial production of the computer of the ENIAC type with vacuum tubes, and they realized the machine that performs the additions and subtractions in decimal 4 digits in 1950. Furthermore, Joh's laboratories's people and he started on the research and trial production of the binary serial computer (nicknamed "Osaka University Vacuum Tube Electronic Computer"), the clock was 1 MHz, which referred to the literature on the EDSAC, the Binac, and others. Associate Professor Makinouchi Saburo and Research Assistant Yasui mainly performed the design and construction of these machines that the hardware was carried out by handmade in the laboratory.

In 1961, he fabricated the SALI (Symbolic Address Language Input routine) as a one pass assembler for domestic computers, such as the NEAC 2203, and 2206. Furthermore, he aspired to the implementation of the user oriented system, and he provided the MALT (Mnemonic Assembly Language Translator) system which a user can define the name of instruction code of a machine with user's mnemonic code (he had the intention of which the definable objects include the informations of a decoder and an encoder in a CPU.) in 1963. This was the one pass assembler that equipped with the dynamic debugging system which is controlled with the symbolic address accompanied by a relative address. These systems were used for users in the Computing Center of Common Use in Osaka University. These days, he was also performing the researches and implementations of the mathematical library and utility programs for the center.

Since he engaged in studies in computer, he had interested in a non-numerical computation. Accordingly, he manufactured the LISP interpreter in 1966. And he attained the research results, such as the system was named the "Self -programming system" under the title of "A trial of the system which it makes a program by the computer itself." in 1967. In these years, he participated in the research and realization of the TSS (named "HANDAI MAC system") that was carried out by the joint research of NEC, NTT and Osaka University, and the system was completed in 1967. He performed the research and implementation of the system for mechanization of the test of a software by the computer in 1968, and he also contributed to developing the TSS. Moreover, he was engaged to keep the facilities in good working order for the Common Use Large Scale Computer Center of Osaka University. And he participated and implemented in the research experiment of the computer network between Tohoku University and Osaka University in 1973. From this year, he took part in the design of the First-stage Common Entrance Examination Center of the National Universities Association and its processing system.

He performed research and implementation of the multiple precision arithmetic Fortran package in which an error estimation and an interval arithmetic are possible in 1974. The scholars in Yokoyama Tamotsu's laboratory of the Department of Economics of Osaka University and he developed the decision-making system CAPSS (Computer Assisted Problem Solving System) in 1977. This system was an application for a TSS and symbol manipulation with multiple users environment.

He proposed a Lisp parallel processing machine named "EVLIS machine" prior to the world in 1979. In 1982, the EVLIS machine was implemented by which the handmade hardware and its software were realized and worked in his laboratory. Although the number of parallel processors of EVLIS machine was eight EVAL processors for the design specification, only three EVAL processors were mounted. Even if the EVLIS machine was single EVAL processor, the EVLIS machine was comparable to the Lisp execution speed on the highest model of an ultra large scale general purpose computer in the world. Since Prolog was implemented with microprogram on the EVLIS machine, the EVLIS machine worked as a Prolog machine in 1984.

He proposed the "Neuro-LISP" in 1988 in order to promote practical use of a vector computer, and he developed and experimented the Neuro-LISP on the supercomputer SX-2N of NEC. He proposed and created the joint system of the neuro-engines and the EVLIS machine as an experiment in 1989. The neuro-engine was made by NEC that the engine was constructed by the data flow architecture. In 1990, he proposed and performed the research of the "Vectorization LISP compiler" for a super computer. The result of this research had gained the value of 99.8% at the rate of the vectorization in the performance monitor data under execution of some Lisp programs on the SX-2N.

These researches and activities were mainly done at the computing machine laboratory in the Department of Applied Physics, Faculty of Engineering of Osaka University, since 1963. He resigned Osaka University by retirement age in March, 1990, and became a professor of the Department of Information System Engineering, Faculty of Engineering of Osaka Sangyo University from April. He resigned Osaka Sangyo University again too under the age limit in 1998, and is continuing a part-time lecturer of the same university till present. He graduated from the Department of Electrical Engineering, Faculty of Science and Engineering of Kinki University in 1960, and received the degree of Doctor of Engineering from Osaka University in 1969.