Automation and the computer
Both old and new materials are used increasingly in
the engineering industry, which has been transformed
since the end of World War II by the introduction of
control engineering, automation, and computerized
techniques. The vital piece of equipment has been the computer,
and especially the electronic digital computer, a
20th-century invention the theory of which was expounded
by the English mathematician and inventor Charles
Babbage in the 1830s. The essence of this machine is the
use of electronic devices to record electric impulses
coded in the very simple binary system, using only two
symbols, but other devices such as punched cards and
magnetic tape for storing and feeding information have
been important supplementary features. By virtue of the
very high speeds at which such equipment can operate,
even the most complicated calculations can be performed
in a very short space of time.
The Mark I digital computer was at work at
Harvard University in 1944, and after the war the
possibility of using it for a wide range of industrial,
administrative, and scientific applications was quickly
realized. The early computers, however, were large and
expensive machines, and their general application was
delayed until the invention of the transistor
revolutionized computer technology. The
transistor is another of the key inventions of the space
age. The product of research on the physics of solids,
and particularly of those materials such as germanium
and silicon known as semiconductors, the transistor was
invented by John Bardeen, Walter H. Brattain, and
William B. Shockley at Bell Telephone Laboratories in
the United States in 1947. It was discovered that
crystals of semiconductors, which have the capacity to
conduct electricity in some conditions and not in
others, could be made to perform the functions of a
thermionic valve but in the form of a device that was
much smaller, more reliable, and more versatile. The
result has been the replacement of the cumbersome,
fragile, and heat-producing vacuum tubes by the small
and strong transistor in a wide range of electronic
equipment. Most especially, this conversion has made
possible the construction of much more powerful
computers while making them more compact and less
expensive. Indeed, so small can effective transistors be
that they have made possible the new skills of
miniaturization and microminiaturization, whereby
complicated electronic circuits can be created on minute
pieces of silicon or other semiconducting materials and
incorporated in large numbers in computers. From the
late 1950s to the mid-1970s the computer grew
from an exotic accessory to an integral element of most
commercial enterprises, and computers made for home use
became widespread in the '80s.
The potential for adaptation and utilization of the computer
seems so great that many commentators have likened it to
the human brain, and there is no doubt that human
analogies have been important in its development. In
Japan, where computer and other electronics
technology has made giant strides since the 1950s, fully
computerized and automated factories were in operation
by the mid-1970s, some of them employing complete work
forces of robots in the manufacture of other robots. In
the United States the chemical industry provides some of
the most striking examples of fully automated, computer-controlled
manufacture. The characteristics of continuous
production, in contrast to the batch production of most
engineering establishments, lend themselves ideally to
automatic control from a central computer
monitoring the information fed back to it and making
adjustments accordingly. Many large petrochemical plants
producing fuel and raw materials for manufacturing
industries are now run in this way, with the residual
human function that of maintaining the machines and of
providing the initial instructions. The same sort of
influences can be seen even in the old established
chemical processes, although not to the same extent: in
the ceramics industry, in which continuous firing has
replaced the traditional batch-production kilns; in the
paper industry, in which mounting demand for paper and
board has encouraged the installation of larger and
faster machines; and in the glass industry, in which the
float-glass process for making large sheets of glass on
a surface of molten tin requires close mechanical
control.
In medicine and the life sciences the computer
has provided a powerful tool of research and
supervision. It is now possible to monitor complicated
operations and treatment. Surgery has made great
advances in the space age. The introduction of
transplant techniques has attracted worldwide publicity
and interest, but perhaps of greater long-term
significance has been the research in biology, with the
aid of modern techniques and instruments, that has begun
to unlock the mysteries of cell formation and
reproduction through the self-replicating properties of
the DNA molecules present in all living substances, and
thus to explore the nature of life itself.
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