Page 81 - DCAP601_SIMULATION_AND_MODELING

Unit 5: Discrete System Simulation (II)

addition, behavior of these generators often changes with temperature, power supply voltage, Notes
the age of the device, or other outside interference. And a software bug in a pseudo-random
number routine, or a hardware bug in the hardware it runs on, may be similarly difficult to
detect.
Generated random numbers are sometimes subjected to statistical tests before use to ensure that
the underlying source is still working, and then post-processed to improve their statistical
properties.

5.4 Summary

 The simulation needs to generate random variables of various kinds, depending on the
system model. This is accomplished by one or more pseudorandom number generators.
 A sequence of pseudo random numbers can be generated by a computer algorithm, such
as the Linear Congruential Method.

5.5 Keywords

Monte Carlo Simulation: References to Monte Carlo simulation are often encountered in the
and simulation literature.
Next Event: Advances the model to the next event to be executed, regardless of the time interval.
Next-event Simulation Model : In next-event simulation model the computer advances time to
the incidence of the subsequent event.
Object-oriented Simulation: Object Oriented techniques have been developed since the early
1960’s as a result of simulation development (SIMULA).

Random Number Generator: Helps to simulate different data coming into the simulation model.
5.6 Self Assessment

Fill in the blanks:
1. An event handler is code, typically a function or routine written in a .................................
language that receives control when the corresponding event occurs.
2. ................................. are the systems with intrinsic randomness or changeability in their
behaviour.

3. A “random number generator” is based solely on ................................. computation.
4. ................................. methods are a class of computational algorithms that rely on repeated
random sampling to compute their results.

5. The simulation needs to generate random variables of various kinds, depending on the
……………………...
6. The initial set of events placed into the pending event set will not have arrival times
representative of the …………………………. distribution.
7. The simulation typically keeps track of the system's ……………….
8. The sequences "appear" to be random, however, and are useful in ………………… and
simulations.
9. The initial choices of multiplier and modulus are that of the ……………… generator.

LOVELY PROFESSIONAL UNIVERSITY 75