Page 235 - DCOM303_DMGT504_OPERATION_RESEARCH

Operations Research

Notes  Basic single server model assumes customers are arriving at Poisson arrival rate with
exponential service times, and first come, first serviced queue discipline, and infinite
queue length, and infinite calling population.
 By adding additional resources to single server system either service rate can be increased
or arrival rate at each server can be decreased with additional cost overhead.

 In Single server single-phase system, customer is served once completed.
 In single server queuing system wait time or performance of system depends on efficiency
of serving person or service machine.

 Single server single-phase queuing system is most commonly automated system found in
our regular life.

11.7 Keywords

Arrival Rate: The number of customers arriving at an average.

Calling Population: Source of customers or messages, the nature of customer numbers.
Queue: A waiting line.
Service Time: The time taken to serve a customer.

Waiting Line System: A system that consists of arrivals in queues, servers and waiting line
structures.

11.8 Review Questions

1. What is the queuing theory?

2. Define arrival rate and service rate.
3. Explain the characteristics of MM1 queuing model.
4. Briefly explain Service Mechanism and Queue Discipline.
5. What is system of steady state?
6. What is multi-server system?

7. Give any four applications of MM1 queuing model.
8. How the time spent in the system is calculated?
9. What is queue discipline?

10. What is traffic intensity?
Answers: Self Assessment

1. (c) 2. (d)
3. (c) 4. Single Phase
5. Arrival 6. Service
7. arrival, service 8. jockeying

9. True 10. False
11. True 12. True

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