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TIME: Almanac 1990
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1990 Time Magazine Compact Almanac, The (1991)(Time).iso
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092589
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09258900.070
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1990-09-17
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TECHNOLOGY, Page 79Time for Some Fuzzy ThinkingAn oddball approach to computer science pays off in JapanBy Philip Elmer-Dewitt
In the pages of Books in Print, listed among works like Fuzzy
Bear and Fuzzy Wuzzy Puppy, are some strange-sounding titles: Fuzzy
Systems, Fuzzy Set Theory and Fuzzy Reasoning & Its Applications.
The bedtime reading of scientists gone soft in the head? No, these
academic tomes are the collected output of 25 years of mostly
American research in fuzzy logic, a branch of mathematics designed
to help computers simulate the various kinds of vagueness and
uncertainty found in everyday life. Despite a distinguished corps
of devoted followers, however, fuzzy logic has been largely
relegated to the back shelves of computer science -- at least in
the U.S.
But not, it turns out, in Japan. As they have so often in the
past, the Japanese have seized on an American invention and found
practical uses for it. Suddenly the term fuzzy and products based
on principles of fuzzy logic seem to be everywhere in Japan: in
television documentaries, in corporate magazine ads and in novel
electronic gadgets ranging from computer-controlled air
conditioners to golf-swing analyzers. The concept of fuzziness has
struck a cultural chord in a society whose religions and
philosophies are attuned to ambiguity and contradiction. Says
Noboru Wakami, a senior researcher at Matsushita: "It's like soy
sauce and sushi -- a perfect match."
What is fuzzy logic? The original concept, developed in the
mid-'60s by Lofti Zadeh, a Russian-born professor of computer
science at the University of California, Berkeley, is that things
in the real world do not fall into the neat, crisp categories
defined by traditional set theory, like the set of even numbers or
the set of left-handed baseball players. In standard Aristotelian
logic, as in computer science, membership in a class or set is not
a matter of degree. Either a number is even, or it is not. But this
on-or-off, black-or-white, 0-or-1 approach falls apart when applied
to many everyday classifications, like the set of beautiful women,
the set of tall men or the set of very cold days.
To deal with such cases, Zadeh proposed that membership in a
set be measured not as a 0 or a 1, but as a value between 0 and 1.
Thus, in the set of tall men, George Bush (6 ft. 2 in.) might have
a membership value of 0.7, while Kareem Abdul-Jabbar (7 ft. 2 in.)
might have a 0.99. Zadeh and his students went on to elaborate a
full fuzzy mathematics, devising precise rules for combining vague
expressions like "somewhat fast," "very hot" and "usually wrong."
This mathematics turns out to be surprisingly useful for
controlling robots, machine tools and various electronic systems.
A conventional air conditioner, for example, recognizes only two
basic states: too hot or too cold. When geared for thermostat
control, the cooling system either operates at full blast or shuts
off completely. A fuzzy air conditioner, by contrast, would
recognize that some room temperatures are closer to the human
comfort zone than others. Its cooling system would begin to slow
down gradually as the room temperature approached the desired
setting. Result: a more comfortable room and a smaller electric
bill.
Fuzzy logic began to find applications in industry in the early
'70s, when it was teamed with another form of advanced computer
science called the expert system. A product of research into
artificial intelligence, expert systems solve complex problems
somewhat like human experts do -- by applying rules of thumb.
(Example: when the oven gets very hot, turn the gas down a bit.)
In 1980 F.L. Smidth & Co. of Copenhagen began marketing the first
commercial fuzzy expert system: a computer program that controlled
the fuel-intake rate and gas flow of a rotating kiln used to make
cement.
Despite such successes, fuzzy logic was not well received in
the U.S. Scientists pointed out that uncertainty and vagueness
could be represented perfectly well by more traditional means, like
statistics or probability theory. Some of the criticism bordered
on the vituperative, and the tenets of fuzzy logic were dismissed
with terms ranging from "comical" to "content-free."
The Japanese, however, showed no such resistance, perhaps
because their culture is not so deeply rooted in scientific
rationalism. Says Bart Kosko, a Zadeh protege and a professor of
electrical engineering at the University of Southern California:
"Fuzziness begins where Western logic ends." In the early '80s
several Japanese firms plunged enthusiastically into fuzzy
research. By 1985 Hitachi had installed the technology's most
celebrated showpiece: a subway system in Sendai, about 200 miles
north of Tokyo, that is operated by a fuzzy computer. Not only does
it give an astonishingly smooth ride (passengers do not need to
hang on to straps), but it is also 10% more energy efficient than
systems driven by human conductors.
Japanese researchers are pursuing more than 100 new
applications for fuzzy logic. Nissan has patented fuzzy auto
transmission and antiskid braking systems. Yamaichi Securities has
introduced a fuzzy stock-market investment program for signaling
shifts in market sentiment. Canon is working on a fuzzy auto-focus
camera. Matsushita has delivered a fuzzy automobile-traffic
controller, and is about to unveil a fuzzy shower system that
adjusts to changes in water temperature to prevent morning
scaldings. And in the strongest endorsement of the technology to
date, the Ministry of International Trade and Industry opened the
Laboratory for International Fuzzy Engineering Research in Yokohama
and called for funding of some $34 million over the next six years.
The U.S. is not totally out of the fuzzy picture yet. A small
firm in Irvine, Calif., Togai InfraLogic, has already achieved
several of the goals MITI set for itself, including a fuzzy
computer chip that can perform 28,600 fuzzy-logical inferences per
sec. (FLIPS). And NASA is experimenting with fuzzy controllers that
could help astronauts pilot the shuttle in earth orbit. The results
so far, say NASA officials, are encouraging, and there is growing
interest at such aerospace firms as Rockwell and Boeing. "The only
barrier remaining" to wider use of fuzzy logic, says Kosko, "is the
philosophical resistance of the West."
-- Norihiko Shirouzu/Tokyo