MGT 6240
MGT 6240
Operations Management
Operations Management
Section 2
Section 2
Case Presentation: Group 1
Case Presentation: Group 1
Cecil Rice Export
Cecil Rice Export
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Zainal
Zainal Abidin
Abidin
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G1039829
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Company Profile
Company Profile
Cecil Rice Export produces white rice in 70
Cecil Rice Export produces white rice in 70
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international markets.
international markets.
The com
The company
pany have bee
have been grow
n growing fast kn
ing fast known
own
for
for low
low cost
cost and
and high
high value.
value.
To acco
To accomod
modate grow
ate growth, they have expa
th, they have expande
nded
d
from single shift in 2005 to three shifts in
from single shift in 2005 to three shifts in
2009.
2009.
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us im
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and lean techniques.
II
ssues to be addressed
ssues to be addressed
Dete
Determine w
rmine whethe
hether the produ
r the production p
ction proces
rocess is
s is
in control or out of control.
in control or out of control.
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An
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differentiate differences among the shifts.
differentiate differences among the shifts.
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shifts in order to provide incentives to senior
shifts in order to provide incentives to senior
personnel to rotate among three
Expanding the number of Shift
2005
08:00-16:00
2007
04:00-12:00
12:00-20:00
2009
00:00-08:00
08:00-16:00
16:00-00:00
Case Summary
Most of the more experienced employees
choose to remain on the day shift (2nd
shift).
When the new shift introduced, most
employees choose the 16:00 to 00:00 (3rd
shift).
The new employees left to the 00:00 to
08:00 (1st shift).
Case Summary
(Cont¶d)
When the shift were added some senior
personnel were assigned to the new shift
to break in to the new workforce but they
choose to their preferred day shift.
The bagging machine fill bags to a
specific weight.
This machine is very sensitive. It
requires calibration by trained
personnel.
When there was only one shift,
there was no problem in weight.
Due to increases in production
company facing weight problem.
The machine is not properly
calibrated.
The ship officer have
detected abnormalities .
The pallets are loaded
with 30 bags each and
suppose to weight 2100
pounds.
Plant manager suspected the bagging operation has
resulted in over or underweight bags.
Overweight bags
decrease the revenue
and
underweight bags are the customer service issue.
Analysis:
Determine control chart
Data is variables with infinite possibilities and
are continuous therefore we need to use
X-bar chart and R-chart.
We are to use X-bar charts to determine
whether changes occured in central tendency
of the process with 99.73% accuracy.
X-bar charts shows whether process
averages is in control or out of control.
Analysis:
Determine control chart
To better understand the variance in each
bags we need to analyze the data through
Range charts.
Range charts point out more or less in
dispersion of the sample means during the
production process.
Analysis
x
z
x
W
U
pper Control Limit (
U
CL) =
Lower Control Limit (
U
CL) =
x
z
W
xx
= mean of the sample means
= number of normal standard deviations (2 for 95.45% confidence, 3 for 99.73%)
x
W
= standard deviation of the sample means =
Z
X-
bar Charts
n/
Wn
= sample size
Analysis (Cont¶d)
Mean population: 70 pounds
Standard Deviation: 1 pound
Sample Size: 5
Cecil Rice Export (Pounds)
Smallest Largest Average UCL LCL
Monday 0:00 70.4 71.8 71.7 70.575 0.447 71.92 69.23 1:00 67.9 70.3 69.2 2:00 70.1 70.6 70.3 3:00 69.2 70 69.5 4:00 69.6 70.6 70.1 5:00 69.7 69.8 69.8 6:00 70.7 72.9 72.6 7:00 69.8 71.5 71.4 Tuesday 0:00 69.1 70.3 69.5 69.8875 0.447 71.23 68.55 1:00 69.6 72.8 70.4 2:00 67.8 70.2 68 3:00 70.5 70.6 70.5 4:00 69.5 71.6 71.3 5:00 70 70.5 70.2 6:00 69.1 70.9 69.3 7:00 69.4 70.8 69.9 Wednesday 0:00 70.7 70.9 70.8 70.4125 0.447 71.75 69.07 1:00 70 71.4 70.6 2:00 68.6 71 70.3 3:00 69.6 71.5 70.2 4:00 68.9 69.2 69.1 5:00 71.1 71.6 71.3 6:00 68.6 69.6 68.8 7:00 69.1 72.4 72.2 x W x
1st Shift (00:00 ± 08:00)
Tuesday
Monday
Wednesday
68 68.5 69 69.5 70 70.5 71 71.5 72 72.5 73 1 2 3 4 5 6 7 8 Average Means UCL LCL Mean of samples mean 68 68.5 69 69.5 70 70.5 71 71.5 72 72.5 73 1 2 3 4 5 6 7 8 Average Means UCL LCL Mean of samples mean 68 68.5 69 69.5 70 70.5 71 71.5 72 72.5 73 1 2 3 4 5 6 7 8 Average Means UCL LCL Mean of samples mean(
X-
bar) 1st
S
hift
Cecil Rice Export (Pounds)
Smallest Largest Average UCL LCL
Monday 8:00 70.0 72.6 71.8 70.0125 0.447 71.35 68.67 9:00 68.2 70.8 68.7 10:00 68.9 69.3 69.1 11:00 69.5 69.7 69.6 12:00 70.5 72 71 13:00 69.7 70.7 70.6 14:00 69.5 70.1 69.7 15:00 69.5 70.8 69.6 Tuesday 8:00 68.3 69.8 68.4 69.8125 0.447 71.15 68,47 9:00 68.7 69.1 68.8 10:00 68.9 71.8 71.4 11:00 70 70.6 70.2 12:00 68.8 70.3 69.7 13:00 68.9 69.7 69.2 14:00 69.7 71.8 70.5 15:00 70 70.6 70.3 Wednesday 8:00 69.7 71.1 70.3 70.2 0.447 71.54 68.86 9:00 70.5 71.3 70.7 10:00 69.3 70.7 69.6 11:00 68.3 71.2 70.8 12:00 68.4 69.9 69.2 13:00 70.1 70.6 70.4 14:00 69.9 70.4 70.2 15:00 70.1 71.1 70.4 x Wx
2nd Shift (08:00 ± 16:00)
Monday
Wednesday
Tuesday
68 68.5 69 69.5 70 70.5 71 71.5 72 72.5 73 1 2 3 4 5 6 7 8 Average Means UCL LCL Mean of samples mean 68 68.5 69 69.5 70 70.5 71 71.5 72 72.5 73 1 2 3 4 5 6 7 8 Average Means UCL LCL Mean of samples mean 68 68.5 69 69.5 70 70.5 71 71.5 72 72.5 73 1 2 3 4 5 6 7 8 Average Means UCL LCLMean of samples mean
Cecil Rice Export (Pounds)
Smallest Largest Average UCL LCL
Monday 16:00 69.5 69.9 69.6 70.125 0.447 71.47 68.78 17:00 68.8 71.9 70.7 18:00 71.1 71.3 71.2 19:00 71.1 71.4 71.3 20:00 70.4 71.2 70.8 21:00 68.9 70.3 69.7 22:00 68.4 68.5 68.5 23:00 69.1 69.3 69.2 Tuesday 16:00 70.2 70.7 70.6 69.6875 0.447 71.03 68,35 17:00 68.5 69.6 69.2 18:00 70.3 70.3 70.3 19:00 69.8 72 69.9 20:00 68.4 70 68.9 21:00 70.1 72.2 70.8 22:00 68.2 69 68.6 23:00 69 69.3 69.2 Wednesday 16:00 69.7 70.1 69.9 69.6625 0.447 71.00 68.32 17:00 68.3 71.4 69.7 18:00 68 71.6 68.1 19:00 70 71.1 70.8 20:00 68.5 71.3 69.2 21:00 67.7 71.2 67.8 22:00 71 71.1 71 23:00 70.5 71.1 70.8 x Wx
3rd Shift (16:00 ± 23:00)
Wednesday
Monday
Tuesday
68 68.5 69 69.5 70 70.5 71 71.5 72 72.5 73 1 2 3 4 5 6 7 8 Average Means UCL LCLMean of samples mean
68 68.5 69 69.5 70 70.5 71 71.5 72 72.5 73 1 2 3 4 5 6 7 8 Average Means UCL LCL
Mean of samples mean
67 67.5 68 68.5 69 69.5 70 70.5 71 71.5 72 1 2 3 4 5 6 7 8 Average Means UCL LCL
Mean of samples mean
Analysis:
X-bar Charts Summary
We find production is erratic and out
of control especially for the 1st shift
We
conclude
that
there
are
assaignable causes in production
process for erratic weights in the bags
of rice.
R-Charts
R
D
UCL
R
!4
R
D
LCL
R
!3
RUCL
=
Upper Control Chart Limit for the Range
R
LCL
3D
R
4D
= Lower Control Chart Limit for the Range
= From 3
Sigma Table
= From 3
Sigma Table
= Average Range of the
Samples
Cecil Rice Export Data (pounds)
day time smallest largest average Range Average of Range/shift Upper Limit Lower Limit
Monday 0:00 70.4 71.8 71.7 1.4 2.67 2.3533 0 1:00 67.9 70.3 69.2 2.4 2:00 70.1 70.6 70.3 0.5 3:00 69.2 70 69.5 0.8 4:00 69.6 70.6 70.1 1 5:00 69.7 69.8 69.8 0.1 6:00 70.7 72.9 72.6 2.2 7:00 69.8 71.5 71.4 1.7 Tuesday 0:00 69.1 70.3 69.5 1.2 3.36 2.9591 0 1:00 69.6 72.8 70.4 3.2 2:00 67.8 70.2 68 2.4 3:00 70.5 70.6 70.5 0.1 4:00 69.5 71.6 71.3 2.1 5:00 70 70.5 70.2 0.5 6:00 69.1 70.9 69.3 1.8 7:00 69.4 70.8 69.9 1.4 Wednesday 0:00 70.7 70.9 70.8 0.2 2.91 2.5630 0 1:00 70 71.4 70.6 1.4 2:00 68.6 71 70.3 2.4 3:00 69.6 71.5 70.2 1.9 4:00 68.9 69.2 69.1 0.3 5:00 71.1 71.6 71.3 0.5 6:00 68.6 69.6 68.8 1 7:00 69.1 72.4 72.2 3.3
1st Shift (00:00 ± 07:00)
(R-Chart) 1
st
shift
Monday
Tuesday
Wednesday
0 0.5 1 1.5 2 2.5 3 1 2 3 4 5 6 7 8 Sample Range UCL LCL avg R 0 0.5 1 1.5 2 2.5 3 3.5 4 1 2 3 4 5 6 7 8 Sample Range UCL LCL Avg R 0 0.5 1 1.5 2 2.5 3 3.5 1 2 3 4 5 6 7 8 Sample Range UCL LCL Avg RCecil Rice Export Data (pounds)
day time smallest largest average Range Average of Range/shift Upper Limit Lower Limit
Monday 8:00 70 72.6 71.8 2.6 2.7 2.3766 0 9:00 68.2 70.8 68.7 2.6 10:00 68.9 69.3 69.1 0.4 11:00 69.5 69.7 69.6 0.2 12:00 70.5 72 71 1.5 13:00 69.7 70.7 70.6 1 14:00 69.5 70.1 69.7 0.6 15:00 69.5 70.8 69.6 1.3 Tuesday 8:00 68.3 69.8 68.4 1.5 2.75 2.4232 0 9:00 68.7 69.1 68.8 0.4 10:00 68.9 71.8 71.4 2.9 11:00 70 70.6 70.2 0.6 12:00 68.8 70.3 69.7 1.5 13:00 68.9 69.7 69.2 0.8 14:00 69.7 71.8 70.5 2.1 15:00 70 70.6 70.3 0.6 Wednesday 8:00 69.7 71.1 70.3 1.4 2.64 2.3300 0 9:00 70.5 71.3 70.7 0.8 10:00 69.3 70.7 69.6 1.4 11:00 68.3 71.2 70.8 2.9 12:00 68.4 69.9 69.2 1.5 13:00 70.1 70.6 70.4 0.5 14:00 69.9 70.4 70.2 0.5 15:00 70.1 71.1 70.4 1
2nd Shift (08:00 ± 16:00)
(R-Chart) 2
nd
Shift
Monday
Tuesday
Wednesday
0 0.5 1 1.5 2 2.5 3 3.5 1 2 3 4 5 6 7 8 Sample Range UCL LCL Avg R 0 0.5 1 1.5 2 2.5 3 1 2 3 4 5 6 7 8 Sample Range UCL LCL Avg R 0 0.5 1 1.5 2 2.5 3 3.5 1 2 3 4 5 6 7 8 Sample Range UCL LCL Avg RCecil Rice Export Data (pounds)
day time smallest largest average Range Average of Range/shift Upper Limit Lower Limit
Monday 16:00 69.5 69.9 69.6 0.4 1.72 1.5145 0 17:00 68.8 71.9 70.7 3.1 18:00 71.1 71.3 71.2 0.2 19:00 71.1 71.4 71.3 0.3 20:00 70.4 71.2 70.8 0.8 21:00 68.9 70.3 69.7 1.4 22:00 68.4 68.5 68.5 0.1 23:00 69.1 69.3 69.2 0.2 Tuesday 16:00 70.2 70.7 70.6 0.5 2.27 2.0038 0 17:00 68.5 69.6 69.2 1.1 18:00 70.3 70.3 70.3 0 19:00 69.8 72 69.9 2.2 20:00 68.4 70 68.9 1.6 21:00 70.1 72.2 70.8 2.1 22:00 68.2 69 68.6 0.8 23:00 69 69.3 69.2 0.3 Wednesday 16:00 69.7 70.1 69.9 0.4 4.02 3.5416 0 17:00 68.3 71.4 69.7 3.1 18:00 68 71.6 68.1 3.6 19:00 70 71.1 70.8 1.1 20:00 68.5 71.3 69.2 2.8 21:00 67.7 71.2 67.8 3.5 22:00 71 71.1 71 0.1 23:00 70.5 71.1 70.8 0.6
3rd Shift (16:00 ± 23:00)
(R-Chart) 3
rd Shift
Monday
Tuesday
Wednesday
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 1 2 3 4 5 6 7 8 Sample Range UCL LCL Avg R 0 0.5 1 1.5 2 2.5 3 3.5 1 2 3 4 5 6 7 8 Sample Range UCL LCL Avg R 0 0.5 1 1.5 2 2.5 1 2 3 4 5 6 7 8 Sample Range UCL LCL Avg RAnalysis Summary: R chart
Analysis)
From R-chart we find the variance of weights in
bags across all shifts are beyond acceptable
control limits
We also find that the production process needs
checking in every shift
x