Assignment -
Consider a pharmacy where customers come to have prescriptions filled. Customers can either have their doctor fax their prescriptions ahead of time and come at a later time to pick up their prescriptions or they can walk in with the prescriptions and wait for them to be filled (i.e. two entity types: fax-in prescription arrivals and customer arrivals). Fax-in prescriptions are handled directly by a pharmacist who fills the prescriptions and leaves the filled prescriptions in a bin behind the counter.
Historical records show that approximately 59 % of customers (whose doctor didn't fax the prescription ahead of time) have faxed their prescriptions ahead of time and the times for a pharmacist to fill a prescription are triangularly distributed with parameters (2, 5, 8) minutes. If an arriving customer has faxed his/her prescription in already, a cashier retrieves the filled prescription and process the customer's payment. Historical records also indicate that the times required for the cashier to retrieve the prescriptions and process payment are triangularly distributed with parameters (2, 4, 6) minutes. If an arriving customer has not faxed the prescription ahead of time, the cashier processes payment and sends the prescription to the pharmacist, who fills the prescription. The distributions of the cashier times and pharmacist times are the same as for the fax-in customers (triangular (2, 4, 6) and triangular (2, 5, 8), respectively). The following table gives the arrival and staffing data where C is the number of cashiers, P is the number of Pharmacists, λ1 is the arrival rate per hour for fax-in prescriptions and λ2 is the arrival rate per hour for customers.
|
Time period
|
C
|
P
|
λ1
|
λ2
|
|
8:00 a.m.-11:00 a.m.
|
1
|
2
|
10
|
12
|
|
11:00 a.m. - 3:00 p.m.
|
2
|
3
|
10
|
20
|
|
3:00 p.m. - 7:00 p.m.
|
2
|
2
|
10
|
15
|
|
7:00 p.m. - 10:00 p.m.
|
1
|
1
|
5
|
12
|
Assume that the pharmacy opens at 8:00 a.m. and closes at 10:00 p.m. and you can ignore faxes and customers that are still in the system at closing time (probably not the best customer service!). Your model should include the following characteristics/features:
a) Entities should move from station to station instantaneously (0 simulated time)
b) Name the object instances your model
c) Create user-defined statistic that tracks the number of customers who walk in with the prescriptions and wait for them to be filled.
d) Create a status plot that displays (1) the instantaneous number of customers in the system, and (2) the average number of customers in the system. The time range for the plot should be from 8:00 a.m. to 10:00 p.m.
e) Create pie charts for resource state of the cashiers and pharmacists.
f) Develop an interesting animation for your model.
g) Create an experiment with 500 replications (8:00 a.m. to 10:00 p.m.)
h) Create experiment responses for the average time customers spend in the system and the scheduled utilizations of the cashiers and pharmacists.
Needs to be done in SIMIO.