Problem 9-09 (Algorithmic) Epsilon Airlines services predominantly the eastern and southeastern united States. The vast majority of Epsilon’s customers make reservations through Epsilon’s website, but

  1. Problem 9-09 (Algorithmic)

Epsilon Airlines services predominantly the eastern and southeastern united States. The vast majority of Epsilon’s customers make reservations through Epsilon’s website, but a small percentage of customers make reservations via phones. Epsilon employs call center personnel to handle these reservations and to deal with website reservation system problems and for the rebooking of flights for customers whose plans have changed or whose travel is disrupted. Staffing the call center appropriately is a challenge for Epsilon’s management team. Having too many employees on hand is a waste of money, but having too few results in very poor customer service and the potential loss of customers.

Epsilon analysts have estimated the minimum number of call center employees needed by day of the week for the upcoming vacation season (June, July, and the first two weeks of August). These estimates are as follows:


Day

Minimum Number of
Employees Needed

Monday

70

Tuesday

45

Wednesday

60

Thursday

90

Friday

45

Saturday

85

Sunday

70

The call center employees work for five consecutive days and then have two consecutive days off. An employee may start work on any day of the week. Each call center employee receives the same salary. Assume that the schedule cycles and ignore start up and stopping of the schedule.

Develop a model that will minimize the total number of call center employees needed to meet the minimum requirements.

Let

Xi = the number of call center employees who start work on day i

 

      (i = 1 = Monday, i = 2 = Tuesday...)


Min

X1 +

X2 +

X3 +

X4 +

X5 +

X6 +

X7

 

 

s.t.

 

 

 

 

 

 

 

 

 

 

X1 +

 

 

X4+

X5+

X6+

X7

 

fill in the blank 2

 

X1 +

X2+

 

 

X5+

X6+

X7

 

fill in the blank 4

 

X1 +

X2+

X3+

 

 

X6+

X7

 

fill in the blank 6

 

X1 +

X2+

X3+

X4+

 

 

X7

 

fill in the blank 8

 

X1 +

X2+

X3+

X4+

X5

 

 

 

fill in the blank 10

 

 

X2 +

X3+

X4+

X5+

X6

 

 

fill in the blank 12

 

 

 

X3 +

X4+

X5+

X6+

X7

 

fill in the blank 14

 

X1,

X2,

X3,

X4,

X5,

X6,

X7

Find the optimal solution.

X1

fill in the blank 15

X2

fill in the blank 16

X3

fill in the blank 17

X4

fill in the blank 18

X5

fill in the blank 19

X6

fill in the blank 20

X7

fill in the blank 21

Total Number of Employees = fill in the blank 22

Give the number of call center employees that exceed the minimum required.

Excess employees:

Monday

fill in the blank 23

Tuesday

fill in the blank 24

Wednesday

fill in the blank 25

Thursday

fill in the blank 26

Friday

fill in the blank 27

Saturday

fill in the blank 28

Sunday

fill in the blank 29