powerpoint presentationmme.uwaterloo.ca/~me380/files/project pl… · ppt file · web view ·...
TRANSCRIPT
![Page 1: PowerPoint Presentationmme.uwaterloo.ca/~me380/Files/Project Pl… · PPT file · Web view · 2009-02-09... which for this data is 2.36 days B, C 2 E A 3 D A 3 C - 5 B - 4 A Precedence](https://reader035.vdocuments.us/reader035/viewer/2022062908/5ae59c0e7f8b9a29048c7866/html5/thumbnails/1.jpg)
ME 380ME 380
Project Planning
![Page 2: PowerPoint Presentationmme.uwaterloo.ca/~me380/Files/Project Pl… · PPT file · Web view · 2009-02-09... which for this data is 2.36 days B, C 2 E A 3 D A 3 C - 5 B - 4 A Precedence](https://reader035.vdocuments.us/reader035/viewer/2022062908/5ae59c0e7f8b9a29048c7866/html5/thumbnails/2.jpg)
Critical Path Method (CPM)Critical Path Method (CPM)
Elements: Activities & EventsFeature: Precedence relations
Activity Duration PrecedenceA 4 -B 5 -C 3 AD 3 AE 2 B, C
Activities Table
![Page 3: PowerPoint Presentationmme.uwaterloo.ca/~me380/Files/Project Pl… · PPT file · Web view · 2009-02-09... which for this data is 2.36 days B, C 2 E A 3 D A 3 C - 5 B - 4 A Precedence](https://reader035.vdocuments.us/reader035/viewer/2022062908/5ae59c0e7f8b9a29048c7866/html5/thumbnails/3.jpg)
Critical Path Method (CPM)Critical Path Method (CPM)
Graphical representation :
Activities :(edges)
Events :(vertices)
CT(Time reqd. for activity)
![Page 4: PowerPoint Presentationmme.uwaterloo.ca/~me380/Files/Project Pl… · PPT file · Web view · 2009-02-09... which for this data is 2.36 days B, C 2 E A 3 D A 3 C - 5 B - 4 A Precedence](https://reader035.vdocuments.us/reader035/viewer/2022062908/5ae59c0e7f8b9a29048c7866/html5/thumbnails/4.jpg)
Critical Path Method (CPM)Critical Path Method (CPM)Precedence:
Activities B & C precede Activity E
C
BE
This “Event” cannot occur before both activities B & C have been completed
![Page 5: PowerPoint Presentationmme.uwaterloo.ca/~me380/Files/Project Pl… · PPT file · Web view · 2009-02-09... which for this data is 2.36 days B, C 2 E A 3 D A 3 C - 5 B - 4 A Precedence](https://reader035.vdocuments.us/reader035/viewer/2022062908/5ae59c0e7f8b9a29048c7866/html5/thumbnails/5.jpg)
Critical Path MethodCritical Path MethodExampleExample
Activity Duration PrecedenceA 4 -B 5 -C 3 AD 3 AE 2 B, C
![Page 6: PowerPoint Presentationmme.uwaterloo.ca/~me380/Files/Project Pl… · PPT file · Web view · 2009-02-09... which for this data is 2.36 days B, C 2 E A 3 D A 3 C - 5 B - 4 A Precedence](https://reader035.vdocuments.us/reader035/viewer/2022062908/5ae59c0e7f8b9a29048c7866/html5/thumbnails/6.jpg)
Critical Path Method (CPM)Critical Path Method (CPM)The project sequence graph is constructed:
C
B
E
A
D
Now what ???ProjectStart
ProjectEnd
![Page 7: PowerPoint Presentationmme.uwaterloo.ca/~me380/Files/Project Pl… · PPT file · Web view · 2009-02-09... which for this data is 2.36 days B, C 2 E A 3 D A 3 C - 5 B - 4 A Precedence](https://reader035.vdocuments.us/reader035/viewer/2022062908/5ae59c0e7f8b9a29048c7866/html5/thumbnails/7.jpg)
Critical Path Method (CPM)Critical Path Method (CPM) Events are consolidated to provide the
specified precedence. “Dummy” activities are added if necessary.
CB
E
A
D
ProjectStart
ProjectEnd
![Page 8: PowerPoint Presentationmme.uwaterloo.ca/~me380/Files/Project Pl… · PPT file · Web view · 2009-02-09... which for this data is 2.36 days B, C 2 E A 3 D A 3 C - 5 B - 4 A Precedence](https://reader035.vdocuments.us/reader035/viewer/2022062908/5ae59c0e7f8b9a29048c7866/html5/thumbnails/8.jpg)
Dummy Activity ExampleDummy Activity ExampleTo be able to bolt a bracket to a panel, the operations
required are : Design bracket A - Build bracket B A Build panel C - Drill holes in panel D A,C
C
BAD
A A
C CD D
B
![Page 9: PowerPoint Presentationmme.uwaterloo.ca/~me380/Files/Project Pl… · PPT file · Web view · 2009-02-09... which for this data is 2.36 days B, C 2 E A 3 D A 3 C - 5 B - 4 A Precedence](https://reader035.vdocuments.us/reader035/viewer/2022062908/5ae59c0e7f8b9a29048c7866/html5/thumbnails/9.jpg)
Critical Path Method (CPM)Critical Path Method (CPM) Activity times (duration) are added next :
CB
E
AD
ProjectStart
ProjectEnd5
3 3
2
4
![Page 10: PowerPoint Presentationmme.uwaterloo.ca/~me380/Files/Project Pl… · PPT file · Web view · 2009-02-09... which for this data is 2.36 days B, C 2 E A 3 D A 3 C - 5 B - 4 A Precedence](https://reader035.vdocuments.us/reader035/viewer/2022062908/5ae59c0e7f8b9a29048c7866/html5/thumbnails/10.jpg)
Critical Path Method (CPM)Critical Path Method (CPM)The CRITICAL PATH is the path through the project on which any
delay will cause the completion of the entire project to be delayed:
CB
E
AD
ProjectStart
ProjectEnd5
3 3
2
4
![Page 11: PowerPoint Presentationmme.uwaterloo.ca/~me380/Files/Project Pl… · PPT file · Web view · 2009-02-09... which for this data is 2.36 days B, C 2 E A 3 D A 3 C - 5 B - 4 A Precedence](https://reader035.vdocuments.us/reader035/viewer/2022062908/5ae59c0e7f8b9a29048c7866/html5/thumbnails/11.jpg)
Critical Path Method (CPM)Critical Path Method (CPM) For fairly simple projects, the critical path is
usually the longest path through the project.
For projects with several parallel and interlinked activities, this may not always be the case.
For more complicated projects, the critical path can be determined with an ‘earliest time’ forward sweep through the diagram followed by a ‘latest time’ reverse sweep.
![Page 12: PowerPoint Presentationmme.uwaterloo.ca/~me380/Files/Project Pl… · PPT file · Web view · 2009-02-09... which for this data is 2.36 days B, C 2 E A 3 D A 3 C - 5 B - 4 A Precedence](https://reader035.vdocuments.us/reader035/viewer/2022062908/5ae59c0e7f8b9a29048c7866/html5/thumbnails/12.jpg)
Critical Path Method (CPM)Critical Path Method (CPM)The EARLIEST starting time of each activity is associated with the events.
It corresponds to the longest time of any path from any previous event.
CB
E
A
D
ProjectStart
ProjectEnd
3 3
2
40
4
975
![Page 13: PowerPoint Presentationmme.uwaterloo.ca/~me380/Files/Project Pl… · PPT file · Web view · 2009-02-09... which for this data is 2.36 days B, C 2 E A 3 D A 3 C - 5 B - 4 A Precedence](https://reader035.vdocuments.us/reader035/viewer/2022062908/5ae59c0e7f8b9a29048c7866/html5/thumbnails/13.jpg)
Critical Path Method (CPM)Critical Path Method (CPM)The LATEST starting time of each activity is also associated with the events.
It corresponds to the longest time of any path from any subsequent event.
CB
E
A
D
ProjectStart
ProjectEnd
3 3
2
40
4
975
0
4
7 9
![Page 14: PowerPoint Presentationmme.uwaterloo.ca/~me380/Files/Project Pl… · PPT file · Web view · 2009-02-09... which for this data is 2.36 days B, C 2 E A 3 D A 3 C - 5 B - 4 A Precedence](https://reader035.vdocuments.us/reader035/viewer/2022062908/5ae59c0e7f8b9a29048c7866/html5/thumbnails/14.jpg)
Critical Path Method (CPM)Critical Path Method (CPM)The CRITICAL PATH is the path along which the earliest time and latest time are
the same for all events, and the early start time plus activity time for any activity equals the early start time of the next activity.
CB
E
A
D
ProjectStart
ProjectEnd
3 3
2
40
4
975
0
4
7 9
![Page 15: PowerPoint Presentationmme.uwaterloo.ca/~me380/Files/Project Pl… · PPT file · Web view · 2009-02-09... which for this data is 2.36 days B, C 2 E A 3 D A 3 C - 5 B - 4 A Precedence](https://reader035.vdocuments.us/reader035/viewer/2022062908/5ae59c0e7f8b9a29048c7866/html5/thumbnails/15.jpg)
Critical Path Method (CPM)Critical Path Method (CPM) This project cannot be completed in less than 9 weeks given the expected duration of the activities. However, activities B & D could be delayed or extended by up to 2 weeks each without affecting
the minimum project completion time. This is termed ‘float’ or ‘slack’ time.
CB
E
A
D
ProjectStart
ProjectEnd
3 3
2
40
4
975
0
4
7 9
![Page 16: PowerPoint Presentationmme.uwaterloo.ca/~me380/Files/Project Pl… · PPT file · Web view · 2009-02-09... which for this data is 2.36 days B, C 2 E A 3 D A 3 C - 5 B - 4 A Precedence](https://reader035.vdocuments.us/reader035/viewer/2022062908/5ae59c0e7f8b9a29048c7866/html5/thumbnails/16.jpg)
ExampleExample Activity Duration PrecedenceA 3 -B 3 AC 4 -D 1 CE 3 B, DF 2 A, B, DG 2 C, FH 4 GI 1 CJ 3 E, GK 5 F, H, I
![Page 17: PowerPoint Presentationmme.uwaterloo.ca/~me380/Files/Project Pl… · PPT file · Web view · 2009-02-09... which for this data is 2.36 days B, C 2 E A 3 D A 3 C - 5 B - 4 A Precedence](https://reader035.vdocuments.us/reader035/viewer/2022062908/5ae59c0e7f8b9a29048c7866/html5/thumbnails/17.jpg)
ExampleExample
C
B EA
DProjectStart Project
End
HK
JF
I
G
![Page 18: PowerPoint Presentationmme.uwaterloo.ca/~me380/Files/Project Pl… · PPT file · Web view · 2009-02-09... which for this data is 2.36 days B, C 2 E A 3 D A 3 C - 5 B - 4 A Precedence](https://reader035.vdocuments.us/reader035/viewer/2022062908/5ae59c0e7f8b9a29048c7866/html5/thumbnails/18.jpg)
ExampleExampleActivity Duration Earliest
StartLatest Start
Float
A 3 0 0 0B 3 3 3 0C 4 0 1 1D 1 4 5 1E 3 6 13 7F 2 6 6 0G 2 8 8 0H 4 10 10 0I 1 4 13 9J 3 10 16 6K 5 14 14 0
![Page 19: PowerPoint Presentationmme.uwaterloo.ca/~me380/Files/Project Pl… · PPT file · Web view · 2009-02-09... which for this data is 2.36 days B, C 2 E A 3 D A 3 C - 5 B - 4 A Precedence](https://reader035.vdocuments.us/reader035/viewer/2022062908/5ae59c0e7f8b9a29048c7866/html5/thumbnails/19.jpg)
Summary: CPM StepsSummary: CPM Steps List all activities and expected durations.
Construct CPM diagram for activities list.
Determine EARLIEST start time for each event (working forward from project start).
Determine LATEST start time for each event (working backwards from project end).
Identify the CRITICAL PATH (and the ‘float’ time for any non-critical activities).
![Page 20: PowerPoint Presentationmme.uwaterloo.ca/~me380/Files/Project Pl… · PPT file · Web view · 2009-02-09... which for this data is 2.36 days B, C 2 E A 3 D A 3 C - 5 B - 4 A Precedence](https://reader035.vdocuments.us/reader035/viewer/2022062908/5ae59c0e7f8b9a29048c7866/html5/thumbnails/20.jpg)
Using Estimates of Activity timesUsing Estimates of Activity times
The estimated duration of any activity is just that – an estimate.
There is usually an optimistic time (shortest time, TS) associated with any activity – 1 in 100 chance of taking less time than this.
There is also usually a pessimistic time (longest time, TL) associated with any activity – 1 in 100 chance of taking longer than this.
If TM is the most likely time for a specific activity, then a mean and variance for the activity can be calculated, assuming that TS, TL and TM are the parameters describing a Beta distribution.
![Page 21: PowerPoint Presentationmme.uwaterloo.ca/~me380/Files/Project Pl… · PPT file · Web view · 2009-02-09... which for this data is 2.36 days B, C 2 E A 3 D A 3 C - 5 B - 4 A Precedence](https://reader035.vdocuments.us/reader035/viewer/2022062908/5ae59c0e7f8b9a29048c7866/html5/thumbnails/21.jpg)
Using Estimates of Activity timesUsing Estimates of Activity times
The estimated time TEST is calculated as:
TEST = (TS + 4.TM + TL)/6
and the variance of this is:
2 = (TL – TS)2/36
![Page 22: PowerPoint Presentationmme.uwaterloo.ca/~me380/Files/Project Pl… · PPT file · Web view · 2009-02-09... which for this data is 2.36 days B, C 2 E A 3 D A 3 C - 5 B - 4 A Precedence](https://reader035.vdocuments.us/reader035/viewer/2022062908/5ae59c0e7f8b9a29048c7866/html5/thumbnails/22.jpg)
from the previous Examplefrom the previous ExampleActivity Duration
TM
TS TL TESTEarliest
StartLatest Start
Float
A 3 1 5 3.0 0 0.5 0.5B 3 2 4 3.0 3 3.5 0.5C 4 3 10 4.83 0 0 0D 1 1 5 1.67 4.83 4.83 0E 3 2 6 3.33 6.50 14.84 8.34F 2 1 7 2.67 6.50 6.5 0G 2 1 4 2.17 9.17 9.17 0H 4 3 6 4.17 11.34 11.34 0I 1 0 3 1.17 4.83 14.34 9.51J 3 1 6 3.17 11.34 18.17 6.83K 5 3 12 5.83 15.51 15.51 0
![Page 23: PowerPoint Presentationmme.uwaterloo.ca/~me380/Files/Project Pl… · PPT file · Web view · 2009-02-09... which for this data is 2.36 days B, C 2 E A 3 D A 3 C - 5 B - 4 A Precedence](https://reader035.vdocuments.us/reader035/viewer/2022062908/5ae59c0e7f8b9a29048c7866/html5/thumbnails/23.jpg)
PERT/CPMPERT/CPMThe critical path has now become C-D-F-G-H-Kwith a total estimated time of 21.3 days
(i.e. 15.51 + 5.83)
The std. deviation along the critical path is the square root of the sum of the individual variances:
CP = C2 + D
2 + F2 + G
2 + H2 + K
2
which for this data is 2.36 days