Teacher: Dr. Ernesto Gutierrez Miravete

Labs 5,6,7
Present:
Pedro Pérez Villanueva
November 17 2003

Lab 5
1. Consider the operation of a fast food restaurant where customers arrive for ordering lunch. The following is a long of the time (minutes) between arrivals of 40 sucessive customers. Use Stat:Fit to analyze the data and fit an appropiate continuos distribution to the date. What are the parameters of the distribution.?
The dates are:
11 11 12 8 15 14 15 13
9
12
8
11
13
12
8
10
14
7
17
16
9
13
15
10
14
12
10
11
9
16
7
12
13
7
16
14
7
10
11
15
The data were analyzed and the best continuous distribution is shown below and is LOGNORMAL[-742,6.63,0.00376]. The graph for this distribution is shown below, along with other distributions that also fit the data.

2. The servers at the above restaurant took the following time (minutes) to serve foodto these 40 customers. Use Stat:Fit to analyze the data and fit an appropiate continuos distribution to the data. What are the parameters of this distribution?.
11
9
12
10
11
13
12
8
10
12
14
11
17
13
8
10
13
12
10
15
14
12
10
11
14
9
16
7
12
15
13
11
13
14
13
12
10
11
15 11
The data were analyzed and the best continuous distribution is shown below and is BETA[7,17,2.67,2.84]. The graph for this distribution is shown below, along with other distributions that also fit the data.

3. The following is the number of incoming calls (each hour for 80 successive hours) to a call center set up for service customers of a certain
Internet service provider. Use Stat:Fit to analyze the data and fit an appropiate distribution to the data. What are the parameters distribution.?
12
9
12
10
12
13
12
8
11
14
11
17
13
10
13
12
12
14
12
10
16
9
16
7
11
13
11
13
10
12
10
11
11
9
12
10
11
11
13
12
8
10
12
14
11
17
13
8
10
13
12
10
15
14
12
10
11
14
9
16
7
12
15
13
11
13
14
10 8 17 12 10 7
BINOMIAL[22,0.533]., it is the only one that fit the data.
13
The data were analyzed and the best discrete distribution is shown below and is
11
13
12
10
11
15

4. Observations were taken on the times to serve online customers at a stockbroker´s site (Stock.COM) on the internet. The times (in seconds) are shown below, sorted in ascending order. Use Stat Fit and Fit an appropiate distribution to the data . What are the parameters of this distribution.?
1.39
3.59
7.11
8.34
21.47
22.55
28.04
28.97
39.49
39.99
41.42
42.53
58.78
60.61
63.38
65.99
82.10
83.52
85.90
88.04
11.14 29.05 47.08 66.00 88.40
11.97 35.26 51.53 73.55 88.47
13.53 37.65 55.11 73.81 92.63
16.87 38.21 55.75 74.14 93.11
17.63 38.32 55.85 79.97 93.74
19.44 39.17 56.96 81.66 98.82
The data were analyzed and the best continuous distribution is shown below and is
UNIFORM[1,98.8]. The graph for this distribution is shown below, along with other distributions that also fit the data.

Ejercise l.6.1

L6.2

l6.3

l 6.4

l6.5

l6.6.1

l6.6.2

l6.7.1

l6.7.2

lab6.8

l6.9

l6.10.1

lab_6.10.2

lab6.10.3

L6.10.4

Lab 7

1. For the example in Section L7.1 insert a DEBUG statement when a garment is sent back for rework. Verify that simulation model is actually sending back garments for rework. Verify that the simulation model is actually sending back garments for rework to the location named Label_Q.

2. For the example in Section L6.1 (Pomona Electronics), trace the model to verify that the circuit boards of type are following the routing as given in Table L6.1.

3. For the example in Section L6.5 (Poly Casting Inc.), run the simulation model and launch the debugger from the options menu.
Turn on the Local Information in the Basic Debugger. Verify the values of the variables WIP and Prod_Qty.

1. Visitors arrive at Kid´s World entertainment park according to an exponential interrarival time distribution with mean 2.5 minutes. The travel time for the entrance to the ticket window is normally distributed with mean of three minutes and standard deviation of 0.5 minute. At the ticket window, visitors wait in a single line until one of six cashiers is available to serve them. The time for the purchase of tickets is normally distributed with mean of five minutes and standard deviation of one minute. After purchase ticket, the visitors go their respective gates to enter the park,
Create a simulation model, with animation, of this system. Run the simulation model for
200 hours to determine: a. The average and maximum length of the ticketing queue b. The average number of customers completing ticketing per hour. c. The average utilization of the cashiers. d. Do you recommend that management add more cashiers?
2. A consultant recommended that six individual queues be formed at athe ticket window
(one for each cashiers) instead of one common queue. Create a simulation model, with animation of this system. Run the simulation model for 200 hours to determine: a. The average and maximum length of the ticketing queues. b. The average number of customers completing ticketing per hour. c. The average utilization of cashiers. d. Do you agree with the consultant’s decision? Would you recommend a raise for the consultant?
3. At the Southern California Airline’s traveler check in facility, three types of customers arrive: passengers with e-ticket (Tipe e), passengers with paper ticket (Type t), and passengers that need to purchase ticket (Type P),
The interarrival distribution and the service times for these passenger are given in the table . Create a simulation model, with animation, of this system. Run the simulation model for 2000 hours. If each type of passenger is served by separate gate agents, determine the following: a. The average and maximum length of the three queues. b. The average number of customers of each type completing check-in procedures per hour. c. The average utilization of the gate agents. d. Would you recommend one single line for check-in for all three types of travelers? Diuscuss the pros and cos for such a change.
4 Raja & Rani, a fancy restaurant in Santa Clara, holds a maximum of 100 dinners.
Customers arrive according to an exponential distribution with a mean of 35. Customers stay in the restaurant according to a triangular distribution with a minimum of 30 minutes, a maximum of 60 minutes, and a mode of 45 minutes. Create a simulation model, with animation of this system. a. Beginning empty, how long is it before the restaurant fills? b. What is the total number of dinner entering the restaurant before it fills?.

c. What is the utilization of the restaurant?.
5. United Electronics manufactures small custom electronic assemblies. There are
four station through which the parts must be processed: assembly, soldering , painting, and inspection. Orders arrive with an exponential interarrival distribution (mean
20 minutes). The process time distribution are shown in the table.
The soldering operation can be perfomed on three jobs at a time. Painting can be done on four jobs at a time . Assembly and inspection are perfomed on one job at time. Create a simulation model. With animation, of this system. Simulate this manufacturing system for 100 days, eight hours each day. Collect and print statiscs on the utilization of each station, associated queues. And the total number of jobs manufactured during each eighhour shift (average).
6. Consider the exercise 5 with the following enhancements. Ten percent of all finished assemblies are sent back to soldering for rework after inspection. Five percent are sent back to assembly for rework after inspection, and one percent of all assemblies fail to pass and are scrapped.
Create a simulation model, with animation, of this system. Simulate this manufacturing system for 100 days, eight hours each day. Collect and print statistics on the utilization of each station, associated queues, total number of jobs assembled, number of assemblies sent for rework to assembly and soldering, and the number of assemblies scrapped during each eight-hour shift (average).
10. At the Pilot Pen Company, a modeling machine produces pen barrels go to a filling machine where ink of appropiate color is filled at the rate of 20 pens per hour
(exponentially distributed). Another modeling machine makes caps of three different colors-red,blue, and green-in the ratio of 3:2:1. The molding time is triangular (2,3,4) minutes per capo. At the next station, caps and filled barrels of matching colors are joined together. Simulate for 300 hours. Find the average number of pens produced per hour.
Collect statistics on the utilization of the molding machines and the joining equipment.
11. Customers arrive at the NoWaitBurger hamburger stand with an interrarival time that is exponentially distributed with a mean of one minut. Out of 10 customers, five buy a hamburger and a drink, three buy a hamburger, and two buy just a drink. One server handles the hamburger while another handles the drink. A person buying both items needs to waiting line for both servers. The time it takes to serve a customer is normally distributed with a mean of 70 seconds for each item Simulate for 100 days, eight hours each days. Collect stastics on the number of customers served each day, size of the queues, and utilization of the servers. What changes would suggest to make the system more efficient?.
12. Workers who work at the Detriot Tool Ndie plant must check out tools from a tool crib.
Workers arrive according to an exponential distribution with a mean time between arrivals of five minutes. At present, three tool crib clerks staff the tool crib. The time to serve a worker is normally distributed with a mean of 10 minutes and a standard deviation of two minutes. Compare the following servicing methods. Simulate for a 24-hour period and collect data. a. Workers from a single queue, choosing the next available tool crib clerk. b. Workers enter the shortest queue (each clerk has his/her own queue). c. Workers choose one of three queues at random.