**UNIVERSITY EXAMINATIONS 2017/2018**

**EXAMINATION FOR THE DEGREE OF BACHELOR OF SCIENCE IN**

**INFORMATION TECHNOLOGY/ BACHELOR OF BUSINESS IN**

**INFORMATION TECHNOLOGY**

**BIT 2201/BBIT 308: SIMULATION AND MODELING **

**FULL TIME/PART TIME/DISTANCE LEARNING**

**DATE: DECEMBER, 2017 TIME: 2 HOURS**

**INSTRUCTIONS: Answer Question One & ANY OTHER TWO questions.**

**QUESTION ONE: 30 MARKS (COMPULSORY)**

a) Discuss five applications of simulation and modeling in real life 5 Marks

b) Using the mid- square method obtain the first five random variables using Z0= 7182.

5Marks

c) Discuss any five desirable features of a good simulation software 5 Marks

d) Discuss five characteristics of a good arithmetic random number generator 5 Marks

e) Discuss five reasons why it is necessary to use animation during the process of modeling and

simulation. 5 Marks

f) Discuss any five advantages of simulation 5 Marks

**QUESTION TWO: 20 MARKS**

a) Describe the following terms giving examples from the air traffic system 5 Marks

i. State of a System

ii. State Variables

iii. Entity

iv. Attribute

v. Event

b) Every system exists with an environment. Activities in the systems environment cause

changes in the state of the system. These activities are classified into categories: Endogenous

and Exogenous. Differentiate between the two. 2 Marks

c) Discuss three reasons why it is not possible to perform experiment with a real system.

3 Marks

d) Describe five common statistics included in the output report of a simulation programming

system. 10 Marks

**QUESTION THREE: 20 MARKS**

a) There are two fundamental types of animation; concurrent and post-processed Differentiate

between the two types of animation. 4 Marks

b) Differentiate between the following types of models 6 Marks

i. Deterministic Vs Stochastic Models

ii. Discrete Models Vs Continuous Models

c) Discuss any four drawbacks simulation and modeling. 6 Marks

d) Using the Linear Congruential Generator (LCG) with a=5, m=16, c=3 and seed Z0 = 7 to

generate the first FIVE random variates on [0,1]. 4 Marks

**QUESTION FOUR: 20 MARKS**

a) Define the terms verification and validation in the context of modeling. 4 Marks

b) Not all simulation and modeling exercises are a success. Discuss five common pitfalls to

successful simulation. 5 Marks

c) Consider a single server queuing system. The system starts at time t=0. The arrival time of

customers is: 1.2, 1.7, 2.4, 4.0, 6.4, 7.0, 8.0, 8.9, and 9.6. The departure times are: 3.0, 4.6,

5.5, 6.0 and 10.0. Time is in minutes. The first in first out queuing discipline is followed.

Simulate this system for six clients and estimate:

i) The average delay in the waiting line 4 Marks

ii) The average number of clients in the waiting line at time t 4 Marks

iii) The expected utilization of server 3 Marks

**QUESTION FIVE: 20 MARKS**

a) Using the banking systems as an example describe the components of a discrete-event system

10 Marks

b) The table below shows the probability distribution of a container arriver per day at Mombasa

port.

The offloading rate per day follows the probability distribution given below. NB: Offloading is

done on FCFS basis.

Suppose the following are the random numbers of arrivals and random numbers of unloading.

Arrival Random No. 52, 06, 50, 88, 53, 30, 10, 47, 99, 37, 66, 91, 35, 32, 00

Offload Random No. 37, 63, 28, 02, 74, 35, 24, 03, 29, 60, 74, 85 90, 73, 59

Required: determine: simulate a fifteen day analysis and determine:

i. The average number of container delayed 4 Marks

ii. The average number of arrivals per day 3 Marks

iii. The average number of containers offloaded each day 3 Marks