Basically an inquisitive creature, Man has sought throughout

          history to comprehend the various natural and social systems

          around him.  Until the advent of sufficiently sophisticated

          computers in the l950's, however, such a lust for knowledge

          generally went unsatisfied, since it was all but impossible to

          scale down a complex system where it could be analyzed easily.

          The number of interacting variables was simply too great for the

          construction of an accurate simulation.  The development of

          powerful computers changed much of this.  Here at last was a tool

          that could store vast quantities of data, interrelate the many

          factors of an intricate system, and clarify the implications of

          these interrelationships.  But as there are different systems to

          analyze, so too are there different types of simulations to most

          accurately model the unique qualities of the different systems.


            Fundamentally, there are two classes of simulation.  The first

          is scientific simulation, where systems have hard, fast, and

          unvarying rules to govern their function.  An example of a

          scientific simulation could be the modeling of a hydroelectric

          power station, where the average flow of the river, the

          resistance of the dam, and the efficiency of the turbines are all

          known.  Given two variables the third can be calculated with

          certainty.  Nothing is left to speculation or guesswork.


            The second type of computer simulation I shall call abstract

          simulation, such as that which is used in the military.  These

          are different from scientific simulations because they can be




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          biased by the simulation designer.  There is no true military

          science to provide well-defined rules of conflict, so many

          questions remain.  What has a more pronounced effect in battle,

          troop morale or weapon range?  How important will superior

          training be?  How will realtime and chance figure into the

          simulation?  These are all crucial questions for the military

          simulation designer.  Following is a closer look at the

          differences between these two classes of simulation.





          1 Simulation in Medicine
          ________________________



            Many encouraging advances in computer simulation have come from

          the medical sciences.  By designing medical simulations, computer

          scientists can play as important a role as physicians themselves

          in keeping the human body in top form.  The typical medical

          application of computers in the past has been keeping records of

          test results, since large hospital labs often generated 3000

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          reports daily, each containing up to twenty results.    So

          initially, the role of the computer was merely that of the book

          keeper, a primitive role compared with what was to come.


            In recent years, medical simulation has grown in quantum leaps

          of sophistication.  One simulation presents medical students with

          common emergency ward cases and a minimal amount of information.

          Many courses of action are open to the student-- additional




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          tests, drug administration, or various types of surgery-- and the

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          results of the actions are determined by the computer.    An even

          more advanced simulation is known as Sim One, and is used in

          anesthesiology.  Sim One is a life size mannequin which

          simulationes heart rate, blood pressure, eye d