# Operations Management Homework Chapter 3

Topics: Harshad number, Bottleneck, Choke point Pages: 6 (1341 words) Published: February 3, 2013
Homework 1 – GMGT 590

Q 3.5
| Step 1: Cut| Step 2: Put Grilled
Stuff on Bagel| Step 3:
Veggies on
Bagel| Step 4:
Cream
Cheese| Step 5:
Wrap|
I| 1| 1| 1| 1| 1|
T| 3 min| 10 min| 5 min| 4 min| 2 min|
R| 0.333333333| 0.1| 0.2| 0.25| 0.5|
%| 100%| 16.67%| 77.78%| 22.20%| 100%|
ADJ R| 0.333333333| .5999| 0.2571| 1.126| 0.5|
| | | | | |
Total Bagel| 180| 100.00%| | | |
Grilled Veggie| 30| 16.67%| | | |
Veggie Only| 110| 61.10%| (+ incoming grilled = 77.78%)| Cream Cheese| 40| 22.20%| | | |
Wrap| 180| 100.00%| | | |

A) Where in the process is the bottle neck? Step 3, Veggies on Bagel, is the bottleneck B) How many units can the process produce within 1 hours? 0.2571 units/minute x 60 minutes = 15.486 units or 15 units

Q 3.7
Part I
| Step 1: Wash| Step 2: Wax| Step 3: Wheel Cleaning| Step 4: Inerior Cleaning| | I| 1| 1| 1| 1| |
T| 10| 10| 7| 20| |
R| 0.1| 0.1| 0.142857143| 0.05| |
%| 100| 0.6| 0.45| 0.3| |
ADJ R| 0.001| 0.17| 0.32| 0.17| |
| | | | | |
Type| Inclusive of| # of Customers per Package| % of Total| Customers per Step| %| Total Cust|  | 40| 100%|  |  |
Package 1| Step 1| 16| 40%| 40| 100|
Package 2| Step 1 and 2| 6| 15%| 24| 0.6|
Package 3| Step 1, 2 and 3| 6| 15%| 18| 0.45|
Package 4| Step 1, 2, 3 and 4| 12| 30%| 12| 0.3|
| | | | | |
Step| Thruput| Cycle| Idle Time| Utilization| |
1| 0.25| 10| 10| 0.333333333| 33%|
2| 0.67| 10| 10| 0.333333333| 33%|
3| 0.95| 7| 13| 0.212121212| 21.20%|
4| 0.17| 20| 0| 1| 100%|

A) What is the implied utilization of the employee doing the wheel cleaning service? 21.2% utilization B) Which resource has the highest implied utilization? Step 4, interior cleaning 100% Part II

| Step 1: Wash| Step 2: Wax| Step 3: Wheel Cleaning| Step 4: Inerior Cleaning| | I| 2| 1| 1| 1| |
T| 10| 10| 7| 20| |
R| 0.2| 0.1| 0.142857143| 0.05| |
%| 1| 0.7| 0.6| 0.5| |
ADJ R| 0.2| 0.14| 0.24| 0.10| |
| | | | | |
Type| Inclusive of| # of Customers per Package| %| # of Customers per Step| %| Total Cust|  | 80| 100%|  |  |
Package 1| Step 1| 24| 30%| 80| 100.00%|
Package 2| Step 1 and 2| 8| 10%| 56| 70.00%|
Package 3| Step 1, 2 and 3| 8| 10%| 48| 60.00%|
Package 4| Step 1, 2, 3 and 4| 40| 50%| 40| 50.00%|

C) What will be the new bottle neck in the process? Step 4, Interior Cleaning D) How many customers a day will not be served? Which customers are going to wait? 0.1cust/min x 60 minute * 12 hours = 72 customers per day

8 customers per day will not be served
The customers who are going to wait are those who select package 4 because it includes step 4 which is the bottle neck. Step 4 can only perform at a thruput rate of 0.1 vehicles per minute as compared to the other steps that perform at a higher rate.

Q. 4.4
Task| Time to Complete (s)| Conveyor Pace|
1| 30| }1,2,3|
2| 25| |
3| 15| |
4| 20| }4,5,6|
5| 15| |
6| 20| |
7| 50| }7,8,9|
8| 15| |
9| 20| |
10| 25| }10,11,12|
11| 15| |
12| 20| |

| Worker 1| Worker 2| Worker 3| Worker 4|
Processing Time| 70 sec| 55 sec| 85 sec| 60 sec|
Capacity| 1/70 unit/sec| 1/55 unit/sec| 1/85 unit/sec| 1/60 unit/sec|  | 0.85 unit/min| 1.09 unit/min| 0.706 unit/min| 1 unit/min| Process Capacity| 0.706 unit/min| | | |

A) Capacity of current line? 1/85 unit per sec or 0.01176 unit per sec (0.706 unit/min)

B) What is the direct labor content?
Labor content = Sum of processing times with labor
Labor content = 70+55+85+60 = 270 seconds per unit
C) What is the average labor utilization?
Average Labor Utilization = Labor content / (labor content + idle time) Average Labor Utilization...