WORKSHEET 3 : THE AIRLINE TICKET COUNTER

An airline ticket counter has stations for 4 ticket agents. Customers are divided into three categories. Type 1 customers (short service) check baggage. Type two customers (medium service) purchase a ticket and check baggage. Type three customers check availability of flights, buy a ticket and check baggage. The arrival and service times are as follows :

All times in mins. | Type 1 | Type 2 | Type 3
Arrival Process (Normal Dist'n.) | 0.75, 0.2 | 3.5, 0.5 | 10.0, 1.0
Service Process (Triangular Dist,n.) | 0.8, 1.0, 1.1 | 2.5, 3.0, 3.2 | 7, 10, 12

The four ticket agents get one-hour breaks each shift, which are staggered over the day such that the first break starts 2 hours into the day. For the next 4 hours, three agents are working (one is on break). Then, 2 more hours with 4 working agents, which completes the shift.

Simulate one 16 hour day, and collect statistics on agents and customers waiting service, and flowtime by customer type.

Consolidation problem, no new statements required.

Additional Work

Devise several verification procedures.

Examine the queue for service as a function of time.

Solution

Number of type 1 customers 1292

Number of type 2 customers 279

Number of type 3 customers 94

Average queue size 3.79