SIMULATION DATES BACK TO 1777 WITH THE QUESTION POSED BY THE BUFFON’S NEEDLE PROBLEM, A SIMPLE MATHEMATICAL METHOD TO REACH THE VALUE OF THE NUMBER ∏ BASED ON SUCCESSIVE ATTEMPTS.
This mathematical model is based on a needle of a certain length dropped onto a plane ruled with parallel lines separated by units. What is the probability of the needle crossing a line?
In 1812 Laplace improved and corrected the Buffon solution and since then it is known as the Buffon-Laplace solution. Later on, the statistician William Sealy Gosset, who worked at the Arthur Guinness Brewery, had already begun to apply statistical knowledge in the brewery and on his own farming estate. The special interest of Gosset in barley crops led him to speculate that experiments should not only be designed with a view to improving average production levels, but they should also aim at developing stronger strains of barley, which were not affected by variations in soil and climate.
To avoid future leaks of confidential information, Guinness forbade his employees to publish any type of article regardless of its content, hence the use that Gosset made in his publications of the pseudonym “Student”, to prevent his employer from discovering his true identity. That is why his most famous achievement is known as the “Student's t-distribution", which otherwise would have been known as Gosset's t-distribution".
This historical milestone opened the doors for the application of simulation in the field of industrial control processes as well as to synergies generated by simulation based on experimentation and analysis techniques, to discover exact solutions to typical industry and engineering problems.
Training period (1945-1970)
In the mid-1940s two events laid the foundations for the rapid evolution of the field of simulation:
· The construction of the first computers used for specific purposes, such as the ENIAC (Electronic Numerical Integrator and Computer).
· The work of Stanislaw Ulam, John Von Neumann and other scientists to use the Montecarlo method in modern computers, solving neutron diffusion problems in the design and development of the hydrogen bomb. Ulam and Von Neumann were present on the Manhattan project.
The Art of Simulation
In 1960, Keith Douglas Tocher developed a general simulation program whose main task was to simulate the operation of a production plant where the machines ran in the following cycles: In use, On Standby, Not available and Fault. Thus, the simulations of status changes would define the definite status of the plant production. This work also led to the first book on simulation: The Art of Simulation (1963).
By that time, IBM had developed, between 1960 and 1961, the General Purpose Simulation System (GPSS). The GPSS was designed to perform teleprocessing simulations, involving, for example: Urban traffic control, management of telephone calls, reservations of plane tickets, etc. The simplicity of use of this system made it popular as the most commonly used simulation language of the era.
On the other hand, SIMSCRIPT was developed in 1963, another alternative technology to GPSS based on FORTRAN, aimed more at users who did not necessarily have to be computer experts from the RAND CORPORATION.
SIMULA I and WSC
In addition to the developments carried out by RAND and IBM, the Royal Norwegian Computing Centre embarked in 1961 on the development of the SIMULA program with the aid of Univac. The result was SIMULA I, probably the most important programming language in history.
In 1967, the WSC (Winter Simulation Conference) was founded, and from then until the present day, records of simulation languages and derived applications are filed there. Today this is the benchmark insofar as advances in the field of simulation systems are concerned.
Expansion Period (1970-1981)
Applications in multiple fields
During this period, advanced modelling and results analysis tools were developed Thanks, too, to the developments obtained in data generation and to the techniques for the optimisation and representation of data, simulation reached its expansion phase, when it began to be applied in many different fields.
Images in movement
Previously, exit data obtained from computers in simulation were presented in the form of graphs or tables; thus, the effect of multiple parameter changes could be reflected, indicating their effect on data. The use of the table format was due to the traditional use made of the table in mathematical models. However, psychologists observed that human beings found it easier to perceive changes in situations when they are expressed graphically or through moving images and animation resulting from these data, similar to animation produced by computers.
