Page 117 - DCAP601_SIMULATION_AND_MODELING

Unit 7: Simulation of Queuing System (I)

Notes

Notes Queuing Theory and Simulation functions hand-in-glove to uncover and smooth
out some of the uneven spots in a productive process - whether this includes delivering a
service or a fabricated item to the instant consumer. When in use a gloved hand discloses
only the glove; but without the hand within the glove is just an empty shell. Simulation
Models only work due to the logical power of Queuing Theory which underlies and
facilitates them

7.3 Computer Simulation for Queuing System

The computer simulation is a method that demonstrates dynamically the structure and the
behaviors of a system with computer in order to evaluate and predict the effect of the behaviors
of some system and provide information for decision. It is an effective way to solve complicated
practical problems. The queuing system is the most typical problem in the discrete event system,
and computer system, communication system and transportation system are all typical tangible
or intangible queuing system. As a result of the widely used queuing system, the queuing
character, the queuing regulation, the service organization become more and more complex so
that the parsing method nearly can’t be obtain. The computer simulation is a quite effective way
for solve the queuing problem and analyzing the performances of the queuing system, which
construct a real system model with computer program, and attain the performances and the
characters changing with time through computation. With the computer simulation, the cost of
the development of the system can be reduced, and the safety of the experiment and the
debugging, thus it will bring great society effort and economic effort. In the queuing model,
data units are often considered as customs and CPUs, transmission lines, channels and terminals
are thought as queue. This is just a queuing model. Because input, computation, transmission,
storage and output are discrete in time field, it is also called discrete queuing model. In real life,
waiting in queue is a common phenomenon, which makes people inconvenient .This paper
takes the payment of minitype supermarket as an example to discuss the computer simulation
for the single-channel and multi-channel queuing system.

Task Analyze an instance of Computer Simulation for Queuing System

Some Conceptions in the Queuing System

The queuing problem is a problem about a balance between average waiting time
and idle time of server, i.e. how to queue to be both good for entity and server.
The queuing theory is a science to solve the problem mentioned as above, and it is also named
random serve theory since the arrival time of entities and the time of serve acceptance is usually
random variable obeying some probability distribution. In the simulation of the queuing system,
there are some conceptions usually being used as below:
1. Entity Arrival Mode: The entity is limited or limitless, and the arrival of the entity is in
individual or in batch. Entity arrival mode is often described with arrival interval. The
random arrival mode applied in the system appears very complex, and different probability
distributions have to be adopted for different systems. Index distribution, normal

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