Philadelphia University Faculty of Information Technology

Lecturer: Dr. Nameer N. EL-Emam Department of CS

Internal Examiner: Dr.Raad Alwan Marking Scheme

Coordinator: Dr. Nameer N. EL-Emam

Module Name: Simulation and Modelling First Exam Semester Two of the academic year:

Module Number: 750472 2014-2015

Date: 6/4/2015 Time One hour

1-Basic part

Objective: This part aims to test students’ skills on the field of model analysis and model development. It means that it is important to convert any model into a suitable form that satisfies the main concepts of a phenomenon through verification and validation.

Q1/(7 marks)

Assume that we have the following continuous system behavior, see figure 1.

ِFigure 1

Answer the following (3 marks for each)

1-Build mathematical model to represent the system behavior.

2-Check verificationof the mathematical model and then using induction algorithm to confirm that the proposed model is valid.

2-Familiar part

Objective:This part aims to test the students' abilities to extract the characteristics from the system behavior

Q2 (7 Marks )

In discrete simulation we have many components to describe and analyze the problem. Theses components are:

Entity, Activity of customer, Process of customer, Events, Activity of events, Resources, Queue, simulation time and Global variables.

Define all components in the time analysis shown in Figure 2 that includes ten customers and dual servers, where (Ajis the arrival time of the jth customer , Siis the time begin for execution at the ithserver, Djis the departure time of the jth customer , and Ci is the ithcustomer )

Figure 2

Unfamiliar part

Objective: The aim of this part is to check student understanding discrete simulation method based on NES

Q3(6 marks )

Assume that we have one queue and one server; apply NES on the discrete model shown in Table 1 to find the time analysis, total waiting time and utilization, then draw your conclusion.

Table 1

Process No. / Inter-arrival Time / Service Time for each Server
1 / 1 / 2
2 / 0 / 3
3 / 1 / 2
4 / 1 / 3
5 / 0 / 2
6 / 1 / 1