Each year, Nikkei AI publishes a survey of expert systems in Japan. For the Nikkei AI Winter 1992 Special Issue (Nikkei AI 1992), questionnaires were sent to 2200 companies, of which 295 responded.1 Figure 2.1 shows that there has been a steady, approximately linear growth in the number of systems, both fielded and under development since 1987.2 The rate of increase in the number of companies that are developing or using the technology has slowed in recent years. Although we are aware of no comparable study for companies in the U.S., we would expect a similar growth pattern.
The number of fielded systems reported in the 1992 survey was analyzed according to the type of application, as shown in Figure 2.2, along with a comparison to previous years. Diagnostic systems have traditionally been the most popular type of ESs. They were first developed 20 years ago (starting with MYCIN; Shortliffe 1976), and now have a well-understood methodology for their construction. The recent upswing in the diagnostic systems is due to two factors: (1) the entry of new ES-user companies; and (2) the application of diagnostic techniques in new areas, such as "help desk" and management analysis.
Figure 2.1. Growth of ESs in Japan (Source: Nikkei AI 1992)
The percentage of ES applications in the planning and design areas is declining, although the absolute number of systems in these areas is increasing because the total number of systems is increasing at a faster rate. Figure 2.2 shows that diagnosis still represents the largest class of applications, although planning (including scheduling) is growing rapidly in importance. Design and control applications are also high enough in numbers to be accorded mention as separate categories. Three examples from our own review of Japanese ESs in scheduling, design and control (all of which have had a high impact on the organizations that use them) are discussed in the next section. Based on our knowledge of activity in the United States, we would expect a similar mix of U.S. application types.
Figure 2.2. Types of ES Applications (Source: Nikkei AI 1992)
The Nikkei AI survey also looked at ES development from the point of view of organizational structure, i.e., who actually builds the systems. Here we see some contrast with the situation in the United States. In Japan, most ESs are built by an organization's MIS group or by its R&D division. Relatively few expert systems are contracted out to external companies. In the U.S., we suspect that a much larger percentage of ESs are built by the numerous companies that specialize in building custom systems (again, no U.S. domestic survey has actually been done). The larger Japanese companies appear to have a tighter coupling among their R&D, product development and operations divisions, so that internal development and deployment of new technology is more easily achieved. Comparing the results shown in Figure 2.3 with previous years, theNikkei AI article comments that there has been an increase in the information systems division as ES builders. There has also been an increase in outsourcing, and a decrease in the laboratories as ES builders. Nikkei AI's editors observe that the category of end users developing their own systems is still small, but is expected to increase as the use of domain-specific tools increases. They also see the movement of application development from the laboratories to the information systems divisions as an indication that ES technology is now in the mainstream.
Figure 2.3. Locus of Development of ESs
(Source: Nikkei AI 1991)
Some other general conclusions from the Nikkei AI survey, for which we found support in our own visits, include:
1 Neither Nikkei AI nor the JTEC panel know if the non-respondents have fielded systems or not. We must assume that some percentage of non-respondents have developed and/or fielded knowledge-based systems. Therefore, the figures quoted in the following discussion must represent minima.
2 The JTEC panel's best guess of the number of fielded systems in Japan is somewhere between 1,000 and 2,000 (including PC-based applications), depending on assumptions about non-respondents to the Nikkei AI surveys.