Transcript heizer_om10_ch03 RRr
3
Project Management
PowerPoint presentation to accompany Heizer and Render Operations Management, 10e Principles of Operations Management, 8e PowerPoint slides by Jeff Heyl © 2011 Pearson Education, Inc. publishing as Prentice Hall 3 - 1
Examples of Projects
Building Construction © 2011 Pearson Education, Inc. publishing as Prentice Hall
Research Project 3 - 2
Project Management Activities
Planning
Scheduling
Objectives
Project activities
Resources
Start & end times
Work break-down structure
Network
Organization
Controlling
Monitor, compare, revise, action © 2011 Pearson Education, Inc. publishing as Prentice Hall 3 - 3
Project Management Techniques
Gantt chart
Critical Path Method (CPM)
Program Evaluation and Review Technique (PERT) © 2011 Pearson Education, Inc. publishing as Prentice Hall 3 - 4
A Simple Gantt Chart
Design Prototype Test Revise Production Time J F M A M J J A S © 2011 Pearson Education, Inc. publishing as Prentice Hall 3 - 5
PERT and CPM
Network techniques
Developed in 1950’s
CPM by DuPont for chemical plants (1957)
PERT by Booz, Allen & Hamilton with the U.S. Navy, for Polaris missile (1958)
Consider precedence relationships and interdependencies
Each uses a different estimate of activity times © 2011 Pearson Education, Inc. publishing as Prentice Hall 3 - 6
Six Steps PERT & CPM
1.
2.
3.
Define the project and prepare the work breakdown structure Develop relationships among the activities - decide which activities must precede and which must follow others Draw the network connecting all of the activities © 2011 Pearson Education, Inc. publishing as Prentice Hall 3 - 7
Six Steps PERT & CPM
4.
5.
6.
Assign time and/or cost estimates to each activity Compute the longest time path through the network – this is called the critical path Use the network to help plan, schedule, monitor, and control the project © 2011 Pearson Education, Inc. publishing as Prentice Hall 3 - 8
A Comparison of AON and AOA Network Conventions
Activity on Node (AON) Activity Meaning (a) A B C A comes before B, which comes before C.
(b) A C A and B must both be completed before C can start.
B A B (c) B and C cannot begin until A is completed.
C © 2011 Pearson Education, Inc. publishing as Prentice Hall Arrow (AOA) A Activity on A B B C A Figure 3.5
C B C 3 - 9
Determining the Project Schedule
Perform a Critical Path Analysis
The critical path is the longest path through the network
The critical path is the shortest time in which the project can be completed
Any delay in critical path activities delays the project
Critical path activities have no slack time © 2011 Pearson Education, Inc. publishing as Prentice Hall 3 - 10
Determining the Project Schedule
Perform a Critical Path Analysis Activity A B C D E F G H Description Build internal components Modify roof and floor Construct collection stack Pour concrete and install frame Build high-temperature burner Install pollution control system Install air pollution device Inspect and test Total Time (weeks) Time (weeks) 2 3 2 4 4 3 5 2 25 © 2011 Pearson Education, Inc. publishing as Prentice Hall Table 3.2
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Determining the Project Schedule
Perform a Critical Path Analysis Earliest start (ES) = earliest time at which an activity can
Activity A Description Build internal components Time (weeks) 2 B C Modify roof and floor Construct collection stack 3 2 D E F Pour concrete and install frame Build high-temperature burner Install pollution control system 4 4 3 G H Install air pollution device
be finished so as to not delay the
Inspect and test 5 2 Total Time (weeks) 25
Table 3.2
© 2011 Pearson Education, Inc. publishing as Prentice Hall 3 - 12
Determining the Project Schedule
Perform a Critical Path Analysis Activity Name or Symbol Earliest Start ES A EF Earliest Finish Latest Start LS 2 LF Latest Finish Figure 3.10
© 2011 Pearson Education, Inc. publishing as Prentice Hall Activity Duration 3 - 13
Forward Pass
Begin at starting event and work forward Earliest Start Time Rule:
If an activity has only a single immediate predecessor, its ES equals the EF of the predecessor
If an activity has multiple immediate predecessors, its ES is the maximum of all the EF values of its predecessors ES = Max {EF of all immediate predecessors} © 2011 Pearson Education, Inc. publishing as Prentice Hall 3 - 14
Forward Pass
Begin at starting event and work forward Earliest Finish Time Rule:
The earliest finish time (EF) of an activity is the sum of its earliest start time (ES) and its activity time EF = ES + Activity time © 2011 Pearson Education, Inc. publishing as Prentice Hall 3 - 15
ES/EF Network for Milwaukee Paper
ES 0 Start 0 EF = ES + Activity time 0 © 2011 Pearson Education, Inc. publishing as Prentice Hall 3 - 16
0 Start 0 0
ES/EF Network for Milwaukee Paper
ES of A EF of A = ES of A + 2 A 0 2 2 © 2011 Pearson Education, Inc. publishing as Prentice Hall 3 - 17
ES/EF Network for Milwaukee Paper
0 Start 0 0 A 2 2 ES of B 0 0 B 3 EF of B = ES of B + 3 3 © 2011 Pearson Education, Inc. publishing as Prentice Hall 3 - 18
ES/EF Network for Milwaukee Paper
0 Start 0 0 A 2 2 0 0 B 3 3 2 C 4 2 © 2011 Pearson Education, Inc. publishing as Prentice Hall 3 - 19
ES/EF Network for Milwaukee Paper
0 Start 0 0 A 2 2 2 C 4 2 = Max (2, 3) 0 0 B 3 3 3 D 4 7 © 2011 Pearson Education, Inc. publishing as Prentice Hall 3 - 20
ES/EF Network for Milwaukee Paper
0 Start 0 0 A 2 2 0 0 B 3 3 2 C 4 2 3 D 7 4 © 2011 Pearson Education, Inc. publishing as Prentice Hall 3 - 21
ES/EF Network for Milwaukee Paper
0 A 2 2 C 4 4 F 7 0 Start 0 0 0 2 B 3 3 2 3 D 7 4 E 8 4 4 3 8 G 13 5 13 H 15 2 © 2011 Pearson Education, Inc. publishing as Prentice Hall Figure 3.11
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Backward Pass
Begin with the last event and work backwards Latest Finish Time Rule:
If an activity is an immediate predecessor for just a single activity, its LF equals the LS of the activity that immediately follows it
If an activity is an immediate predecessor to more than one activity, its LF is the minimum of all LS values of all activities that immediately follow it LF = Min {LS of all immediate following activities} © 2011 Pearson Education, Inc. publishing as Prentice Hall 3 - 23
Backward Pass
Begin with the last event and work backwards Latest Start Time Rule:
The latest start time (LS) of an activity is the difference of its latest finish time (LF) and its activity time LS = LF – Activity time © 2011 Pearson Education, Inc. publishing as Prentice Hall 3 - 24
LS/LF Times for Milwaukee Paper
0 A 2 2 C 4 4 F 7 2 2 3 0 Start 0 0 0 B 3 3 E H 4 8 13 15 13 15 4 LS = LF – Activity time 3 7 8 13 4 5 2 LF = EF of Project © 2011 Pearson Education, Inc. publishing as Prentice Hall 3 - 25
LS/LF Times for Milwaukee Paper
0 Start 0 0 A 2 2 0 0 B 3 3 2 C 2 4 4 10 F 7 3 13 4 E LF = Min(LS of following activity) 4 3 D 7 8 G 13 13 13 H 15 15 2 4 5 © 2011 Pearson Education, Inc. publishing as Prentice Hall 3 - 26
LS/LF Times for
0 Start 0 0 0 A 2 2 0 B 3 3 2 2 C 2 4 4 3 D 7 4 4 E 4 8 8 4 4 10 F 7 3 13 8 8 G 5 13 13 13 13 H 15 15 2 © 2011 Pearson Education, Inc. publishing as Prentice Hall 3 - 27
LS/LF Times for Milwaukee Paper
0 Start 0 0 0 0 0 0 A 2 2 2 0 B 1 3 3 4 2 2 C 2 4 4 3 4 D 4 7 8 4 4 E 4 8 8 4 10 F 7 3 13 8 8 G 5 13 13 13 13 H 15 15 2 © 2011 Pearson Education, Inc. publishing as Prentice Hall 3 - 28
Computing Slack Time
After computing the ES, EF, LS, and LF times for all activities, compute the slack or free time for each activity
Slack is the length of time an activity can be delayed without delaying the entire project Slack = LS – ES or Slack = LF – EF © 2011 Pearson Education, Inc. publishing as Prentice Hall 3 - 29
Computing Slack Time
Activity Earliest Start ES Earliest Finish EF A B C D E F G H 3 4 4 8 13 0 0 2 7 8 7 13 15 2 3 4 Latest Start LS 4 4 10 8 13 0 1 2 Latest Finish LF 8 8 13 13 15 2 4 4 Slack LS – ES On Critical Path 0 1 0 1 0 6 0 0 Yes No Yes No Yes No Yes Yes © 2011 Pearson Education, Inc. publishing as Prentice Hall Table 3.3
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Critical Path for Milwaukee Paper
0 Start 0 0 0 0 0 0 A 2 2 2 0 B 1 3 3 4 2 2 C 2 4 4 3 4 D 4 7 8 4 4 E 4 8 8 4 10 F 7 3 13 8 8 G 5 13 13 13 13 H 15 15 2 © 2011 Pearson Education, Inc. publishing as Prentice Hall 3 - 31
ES – EF Gantt Chart for Milwaukee Paper
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 A Build internal components B Modify roof and floor C Construct collection stack D Pour concrete and install frame E Build high temperature burner F Install pollution control system G Install air pollution device H Inspect and test © 2011 Pearson Education, Inc. publishing as Prentice Hall 3 - 32
LS – LF Gantt Chart for Milwaukee Paper
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 A Build internal components B Modify roof and floor C Construct collection stack D Pour concrete and install frame E Build high temperature burner F Install pollution control system G Install air pollution device H Inspect and test © 2011 Pearson Education, Inc. publishing as Prentice Hall 3 - 33