Simulation Techniques March/April 2000

Part - A

1    a) With suitable examples explain different types models used in
     system studies.     12.
     b) Explain the concept of subsystem and use it to develop a corporate
     model.		8.

2    a) Explain dynamic physical models.                              6.
     b) With suitable examples illustrate the use of system postulations.
     			6.
     c) Describe distributed lag models. Draw a cobweb model for a market
     in which the supply and demand functions are:
		S = 1.0 + 0.9 P-1
		D = 12.4 - 1.2 P
     Assume that initial price is 1.0 and the market is always cleared.
          8.

3    a) Describe the modified exponential growth models and the logistic
     curves and discuss their applications.                         8.
     b) Describe the structure of a system dynamics model. Draw a simple
     system diagram for an inventory control system and explain.    8.
     c) Explain the guiding principles used in modeling.          4.

4    a) Explain the steps involved in system simulation study with a flow
     chart.         10.
     b) What is the need for continuous system simulation language? Give
     a list of some of the functional blocks of CSMP III.         6.
     c) Explain briefly the differences between continuous system
     simulation and discrete system simulation.                   4.
5    a) Explain the inverse transformation and rejection methods for
     generating non-uniform continuously distributed random numbers. 10.
     b) What are the measures of probability functions? Explain.    6.
     c) Explain the commonly needed statistics from a simulation study. 4

                                Part - B

6    a) Explain the following terms with respect to                8.
		i)	Balking		   ii)  Server Utilization	
		iii) Traffic Intensity   iv) Preempt
     b) Explain the following with the GPSS block diagram symbols. 8.
		i)	ADVANCE		ii)  SEIZE
		iii) ASSIGN		iv) DEPART
     c) Discuss the advantages of simulation languages over general
          purpose languages for system simulation.                   4.

7    a) Workers come to a sypply stores at the rate of 1 every 5 +
     minutes. Their requisitions are processed by on of the two clerks who
     take 8 + 4 minutes for each requisition. The requisitions are then
     passed to a single store keeper who fills them one at a time, taking
     4 + 3 minutes for each request. Simulate the queue of workers and
     measure the distribution of time taken for 1000 requisitions to be
     filled.  14.
      b) Describe any 2 standard numerical attributes available in GPSS
     and clearly illustrate their use. 	6.

8    Write Short notes on the following.                      (5 x 4 = 20)
           i) Arrival Patterns.
          ii) Monte Carlo techniques.
         iii) Cobweb Models
          iv) Analog Vs Digital Simulation.
	

