Homework AssignmentHomework AssignmentSimulation ModelingSimulation Modeling

The Cobbler ProblemThe Cobbler Problem

MGMT E - 5065Operations

andLogistics Management

DueSeptember 25th

The Cobbler SimulationThe Cobbler Simulation

A cobbler specializes in same-day shoe repair. Customers dropoff their shoes before 9:00 am and expect them to be ready forpickup by 5:00 pm.There is a risk however, that the work needed on a pair of shoescannot be done that day, depending on the type of repair that isrequired.A simulation spreadsheet was developed to reflect the number of shoes dropped off each morning:

Number of Pairs

Probability RN Intervals

10 .10 00 - 09

15 .25 10 - 34

20 .30 35 - 64

25 .25 65 - 89

30 .10 90 - 99

The Cobbler SimulationThe Cobbler Simulation

Currently, the maximum number of pairs of shoes that can be

mended per day is:

Number of Pairs

Probability RN Intervals

15 .30 00 - 29

20 .40 30 - 69

25 .30 70 - 99

The Cobbler SimulationThe Cobbler Simulation

In the simulation for a specific day, the number of pairs of shoes needingrepair ( NPSNR ) is determined first.

Next, the maximum number of pairs of shoes that could be repaired ( MNPSR ) is determined.

If MNPSR => NPSNR, all pairs of shoes are mended for that day.

If MNPSR < NPSNR, then [ NPSNR - MNPSR ] pairs of shoes must beadded to the number of pairs of shoes arriving the next day in orderto obtain the NPSNR for the next day.

The simulation continues in this manner.

The Cobbler SimulationThe Cobbler Simulation

REQUIREMENT:

1. Assuming the repair shop is empty of shoes at the start, simulate seven (7) days of operation, using the following random number strings:

Dropoffs 53 58 04 83 65 27 49

Capacity 83 44 82 12 08 53 77

The Cobbler SimulationThe Cobbler Simulation

REQUIREMENT:

2. Determine the average daily number of pairs held overnight.

3. Determine the average maximum repair capacity per day.

4. Determine the average daily number of pairs actually mended.

The Cobbler SimulationThe Cobbler Simulation

Day

Random

Number

New

Dropoffs

Queue

At

Day

Start

NPSNR

Random

Number MNPSR

Actual

Pairs

Mended

Queue

At

Day

End

1

2

3

4

5

6

7

Spreadsheet Format