HUMAN-MACHINE RESEARCH IN NUCLEAR POWER

Since Japan has poor energy resources, it has vigorously pursued nuclear power. For obvious reasons, Japan is as sensitive as any nation to the perils of nuclear power and has always imposed rigorous safety measures. Toshiba and Hitachi licensed the designs for boiling water reactors (BWRs) from the United States, built a number of them for the Japanese market, and gradually evolved their own plant designs and operating practices. Mitsubishi Heavy Industries similarly licensed Westinghouse designs. Now Japanese companies are actively competing for BWR and pressurized water reactor (PWR) construction across the Pacific Rim.

Japan has never faltered on introducing computers into nuclear power plants for monitoring, diagnosis, and control. The United States, in stark contrast to Japan (as well as Canada, France, and Germany), has been very reluctant to entrust the regulation of any important functions to computers. The writer believes this is partly due to several bad experiences that U.S. power companies had with computers very early on; partly due to conservative regulatory agency and other political pressures following the Three Mile Island accident; and partly due to the fact that the operating philosophy of the U.S. nuclear power industry grew out of a relatively low-technology perspective of fossil fuel power generation using operating personnel who have military but not formal technical training (except in the field of nuclear physics). Somehow, unlike that other highly regulated industry, commercial aviation, the computer community was never invited in. Japan seems not to have been restrained by such a history.

Notions of human supervisory control, wherein a human operator programs and monitors the automatic computer-execution of a process, were developed in Western countries primarily in space and commercial aviation, and to a lesser extent in the chemical and pharmaceutical industries. In contrast, the Japanese have seen the obvious applications of these ideas to nuclear as well as other process control and manufacturing, and they use operating personnel with formal engineering training. For the last decade, no new nuclear plants have been built in the United States, and the U.S. nuclear service industry is not healthy. The computer-controlled, high-technology plants have remained on the drawing boards. Japan, in contrast, has moved steadily ahead in applying computers and artificial intelligence (AI) to plant design, system monitoring and failure diagnosis, fuel management, and on-line plant control.

The Japanese established the multisite Central Research Institute of the Electric Power Industry (CRIEPI) in 1951, and in 1987 CRIEPI founded its Human Factors Research Center (HFRC) near Tokyo. The research agenda of this organization seems to be closely modeled on the human factors research program of the U.S. Electric Power Research Institute (EPRI) in Palo Alto; the head of the HFRC spent a year at EPRI several years ago. The JTEC team visit to CRIEPI revealed a strong effort to study the behavior of control room operators in teams. A rule-based cognitive model is being developed there in conjunction with simulator-based experiments to characterize how operators deal with emergency procedures. While U.S. systems engineers tend to engage in cognitive modeling with some reserve and trepidation regarding their ability to validate the various cognitive components (e.g., perception, short-term memory, long-term memory, decision-making, speech communication, and motor action), Japanese researchers seem to accept these psychological ideas as applied to the very practical problems of predicting errors and refining procedures.

The JTEC team also visited Toshiba, which has adopted with relish the popular qualitative ideas of Professor Jens Rasmussen on ecological design of human-machine interfaces. "Ecology" in this sense refers to the word's original meaning of interdependence and integration of human and machine functions. Analysis according to Rasmussen's skill-based, rule-based, and knowledge-based levels of interaction is established policy at Toshiba.

Toshiba is also employing "virtual reality" simulation (computer-graphic portrayal of human operators interacting with the control boards) as a tool for reviewing procedures and for training.


Published: March 1996; WTEC Hyper-Librarian