Operation Management
cezinha22
Chapter3PPTBU510.ppt© 2014 Pearson Education, Inc.
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Project Management
3
PowerPoint presentation to accompany
Heizer and Render
Operations Management, Eleventh Edition
Principles of Operations Management, Ninth Edition
PowerPoint slides by Jeff Heyl
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Outline
Global Company Profile:
Bechtel Group
The Importance of Project Management
Project Planning
Project Scheduling
Project Controlling
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Outline - Continued
Project Management Techniques: PERT and CPM
Determining the Project Schedule
Variability in Activity Times
Cost-Time Trade-offs and Project Crashing
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Outline - Continued
A Critique of PERT and CPM
Using Microsoft Project to Manage Projects
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When you complete this chapter you should be able to:
Learning Objectives
- Use a Gantt chart for scheduling
- Draw AOA and AON networks
- Complete forward and backward passes for a project
- Determine a critical path
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Learning Objectives
Calculate the variance of activity times
Crash a project
When you complete this chapter you should be able to:
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Bechtel Projects
Constructing 30 high-security data centers worldwide for Equinix, Inc. ($1.2 billion)
Building and running a rail line between London and the Channel Tunnel ($4.6 billion)
Developing an oil pipeline from the Caspian Sea region to Russia ($850 million)
Expanding the Dubai Airport in the UAE ($600 million), and the Miami Airport in Florida ($2 billion)
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Bechtel Projects
Building liquid natural gas plants in Yemen ($2 billion) and in Trinidad, West Indies ($1 billion)
Building a new subway for Athens, Greece ($2.6 billion)
Constructing a natural gas pipeline in Thailand ($700 million)
Building 30 plants for iMotors.com, a company that sells refurbished autos online ($300 million)
Building a highway to link the north and south of Croatia ($303 million)
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Importance of
Project Management
Bechtel Project Management
International workforce, construction professionals, cooks, medical personnel, security
Strategic value of time-based competition
Quality mandate for continual improvement
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Single unit
Many related activities
Difficult production planning and inventory control
General purpose equipment
High labor skills
Project Characteristics
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Examples of Projects
- Building Construction
- Research Project
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Management of Projects
Planning - goal setting, defining the project, team organization
Scheduling - relate people, money, and supplies to specific activities and activities to each other
Controlling - monitor resources, costs, quality, and budgets; revise plans and shift resources to meet time and cost demands
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- Planning
- Objectives
- Resources
- Work break-down structure
- Organization
- Scheduling
- Project activities
- Start & end times
- Network
- Controlling
- Monitor, compare, revise, action
Project Management Activities
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Project Planning, Scheduling, and Controlling
Figure 3.1
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Project Planning, Scheduling, and Controlling
Figure 3.1
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Project Planning, Scheduling, and Controlling
Figure 3.1
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Project Planning, Scheduling, and Controlling
Figure 3.1
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Project Planning, Scheduling, and Controlling
Figure 3.1
Budgets
Delayed activities report
Slack activities report
Time/cost estimates
Budgets
Engineering diagrams
Cash flow charts
Material availability details
CPM/PERT
Gantt charts
Milestone charts
Cash flow schedules
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Establishing objectives
Defining project
Creating work breakdown structure
Determining
resources
Forming organization
Project Planning
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Often temporary structure
Uses specialists from entire company
Headed by project manager
Coordinates activities
Monitors schedule
and costs
Permanent
structure called
‘matrix organization’
Project Organization
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Project Organization
Works Best When
Work can be defined with a specific goal and deadline
The job is unique or somewhat unfamiliar to the existing organization
The work contains complex interrelated tasks requiring specialized skills
The project is temporary but critical to the organization
The project cuts across organizational lines
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A Sample Project Organization
Figure 3.2
Technician
Project No. 2
Project
Manager
Electrical
Engineer
Computer
Engineer
Test
Engineer
Mechanical
Engineer
Project No. 1
Project
Manager
Technician
Marketing
Finance
Human
Resources
Design
Quality
Mgt
Production
President
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Matrix Organization
Marketing Operations Engineering Finance
Project 1
Project 2
Project 3
Project 4
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The Role of
the Project Manager
Highly visible
Responsible for making sure that:
- All necessary activities are finished in order and on time
- The project comes in within budget
- The project meets quality goals
- The people assigned to the project receive motivation, direction, and information
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The Role of
the Project Manager
Highly visible
Responsible for making sure that:
- All necessary activities are finished in order and on time
- The project comes in within budget
- The project meets quality goals
- The people assigned to the project receive motivation, direction, and information
Project managers should be:
- Good coaches
- Good communicators
- Able to organize activities from a variety of disciplines
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Ethical Issues
- Offers of gifts from contractors
- Pressure to alter status reports to mask delays
- False reports for charges of time and expenses
- Pressure to compromise quality to meet schedules
- Project managers face many ethical decisions on a daily basis
- The Project Management Institute has established an ethical code to deal with problems such as:
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Work Breakdown Structure
Level
1. Project
2. Major tasks in the project
3. Subtasks in the major tasks
4. Activities (or “work packages”)
to be completed
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Work Breakdown Structure
Figure 3.3
Level 4
Compatible with Windows 7
Compatible with Windows Vista
Compatible with Windows XP
1.1.2.3
1.1.2.2
1.1.2.1
(Work packages)
Level 3
Develop GUIs
Design Cost Tracking Reports
Module Testing
Ensure Compatibility with Earlier Versions
Develop Cost/Schedule Interface
Defect Testing
1.1.1
1.2.2
1.3.2
1.3.1
1.2.1
1.1.2
Level 2
Software Design
Cost Management Plan
System Testing
1.1
1.2
1.3
Level 1
Develop Windows 8 Operating System
1.0
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Project Scheduling Techniques
Ensure that all activities
are planned for
Their order of
performance is
accounted for
The activity time
estimates are recorded
The overall project time is developed
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Purposes of Project Scheduling
Shows the relationship of each activity to others and to the whole project
Identifies the precedence relationships among activities
Encourages the setting of realistic time and cost estimates for each activity
Helps make better use of people, money, and material resources by identifying critical bottlenecks in the project
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Gantt chart
Critical Path Method (CPM)
Program Evaluation and Review Technique (PERT)
Project Management Techniques
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A Simple Gantt Chart
Time
J F M A M J J A S
Design
Prototype
Test
Revise
Production
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Service For a Delta Jet
Figure 3.4
Passengers
Baggage
Fueling
Cargo and mail
Galley servicing
Lavatory servicing
Drinking water
Cabin cleaning
Cargo and mail
Flight services
Operating crew
Baggage
Passengers
Deplaning
Baggage claim
Container offload
Pumping
Engine injection water
Container offload
Main cabin door
Aft cabin door
Aft, center, forward
Loading
First-class section
Economy section
Container/bulk loading
Galley/cabin check
Receive passengers
Aircraft check
Loading
Boarding
0 10 20 30 40
Time, Minutes
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Project Controlling
Close monitoring of resources, costs, quality, budgets
Feedback enables revising the project plan and shift resources
Computerized tools produce extensive reports
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Project Management Software
There are several popular packages for managing projects
Primavera
MacProject
MindView
HP Project
Fast Track
Microsoft Project
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Project Control Reports
Detailed cost breakdowns for each task
Total program labor curves
Cost distribution tables
Functional cost and hour summaries
Raw materials and expenditure forecasts
Variance reports
Time analysis reports
Work status reports
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Network techniques
Developed in 1950s
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
PERT and CPM
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Six Steps PERT & CPM
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
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Six Steps PERT & CPM
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
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- When will the entire project be completed?
- What are the critical activities or tasks in the project?
- Which are the noncritical activities?
- What is the probability the project will be completed by a specific date?
Questions PERT & CPM
Can Answer
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- Is the project on schedule, behind schedule, or ahead of schedule?
- Is the money spent equal to, less than, or greater than the budget?
- Are there enough resources available to finish the project on time?
- If the project must be finished in a shorter time, what is the way to accomplish this at least cost?
Questions PERT & CPM
Can Answer
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A Comparison of AON and AOA Network Conventions
Activity on Activity Activity on
Node (AON) Meaning Arrow (AOA)
A comes before B, which comes before C
(a)
A
B
C
B
A
C
A and B must both be completed before C can start
(b)
A
C
C
B
A
B
B and C cannot begin until A is completed
(c)
B
A
C
A
B
C
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A Comparison of AON and AOA Network Conventions
Activity on Activity Activity on
Node (AON) Meaning Arrow (AOA)
A
B
C
D
B
A
C
D
C and D cannot begin until both A and B are completed
(d)
C
A
B
D
Dummy activity
A
B
C
D
C cannot begin until both A and B are completed
D cannot begin until B is completed
A dummy activity is introduced in AOA
(e)
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A Comparison of AON and AOA Network Conventions
Activity on Activity Activity on
Node (AON) Meaning Arrow (AOA)
A
C
D
B
A
B
C
D
Dummy activity
B and C cannot begin until A is completed
D cannot begin until both B and C are completed
A dummy activity is again introduced in AOA
(f)
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AON Example
| Table 3.1 | Milwaukee Paper Manufacturing’s Activities and Predecessors | |
| ACTIVITY | DESCRIPTION | IMMEDIATE PREDECESSORS |
| A | Build internal components | — |
| B | Modify roof and floor | — |
| C | Construct collection stack | A |
| D | Pour concrete and install frame | A, B |
| E | Build high-temperature burner | C |
| F | Install pollution control system | C |
| G | Install air pollution device | D, E |
| H | Inspect and test | F, G |
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AON Network for Milwaukee Paper
Figure 3.5
A
Start
B
Start Activity
Activity A
(Build Internal Components)
Activity B
(Modify Roof and Floor)
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AON Network for Milwaukee Paper
Figure 3.6
C
D
A
Start
B
Activity A Precedes Activity C
Activities A and B Precede Activity D
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AON Network for Milwaukee Paper
Figure 3.7
G
E
F
H
C
A
Start
D
B
Arrows Show Precedence Relationships
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AOA Network for Milwaukee Paper
Figure 3.8
H
(Inspect/ Test)
7
Dummy Activity
6
F
(Install Controls)
E
(Build Burner)
G
(Install Pollution Device)
5
D
(Pour Concrete/ Install Frame)
4
C
(Construct Stack)
1
3
2
B
(Modify Roof/Floor)
A
(Build Internal Components)
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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
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Determining the Project Schedule
| Table 3.2 | Time Estimates for Milwaukee Paper Manufacturing | |
| ACTIVITY | DESCRIPTION | TIME (WEEKS) |
| A | Build internal components | 2 |
| B | Modify roof and floor | 3 |
| C | Construct collection stack | 2 |
| D | Pour concrete and install frame | 4 |
| E | Build high-temperature burner | 4 |
| F | Install pollution control system | 3 |
| G | Install air pollution device | 5 |
| H | Inspect and test | 2 |
| Total time (weeks) | 25 |
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Determining the Project Schedule
Perform a Critical Path Analysis
Earliest start (ES) = earliest time at which an activity can start, assuming all predecessors have been completed
Earliest finish (EF) = earliest time at which an activity can be finished
Latest start (LS) = latest time at which an activity can start so as to not delay the completion time of the entire project
Latest finish (LF) = latest time by which an activity has to be finished so as to not delay the completion time of the entire project
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Determining the Project Schedule
Activity Format
Figure 3.9
Activity Name or Symbol
A
Earliest Start
ES
Earliest Finish
EF
Latest Start
LS
Latest Finish
LF
Activity Duration
2
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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}
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Forward Pass
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
Begin at starting event and work forward
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ES/EF Network for Milwaukee Paper
Start
0
0
ES
0
EF = ES + Activity time
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ES/EF Network for Milwaukee Paper
Start
0
0
0
A
2
2
EF of A =
ES of A + 2
0
ES
of A
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ES/EF Network for Milwaukee Paper
B
3
Start
0
0
0
A
2
2
0
3
EF of B =
ES of B + 3
0
ES
of B
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ES/EF Network for Milwaukee Paper
C
2
2
4
B
3
0
3
Start
0
0
0
A
2
2
0
*
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ES/EF Network for Milwaukee Paper
7
C
2
2
4
B
3
0
3
Start
0
0
0
A
2
2
0
D
4
= Max (2, 3)
3
*
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ES/EF Network for Milwaukee Paper
D
4
3
7
C
2
2
4
B
3
0
3
Start
0
0
0
A
2
2
0
*
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ES/EF Network for Milwaukee Paper
Figure 3.10
E
4
F
3
G
5
H
2
4
8
13
15
4
8
13
7
D
4
3
7
C
2
2
4
B
3
0
3
Start
0
0
0
A
2
2
0
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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}
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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
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LS/LF Times for
Milwaukee Paper
E
4
F
3
G
5
H
2
4
8
13
15
4
8
13
7
D
4
3
7
C
2
2
4
B
3
0
3
Start
0
0
0
A
2
2
0
LF = EF
of Project
15
13
LS = LF – Activity time
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LS/LF Times for
Milwaukee Paper
E
4
F
3
G
5
H
2
4
8
13
15
4
8
13
7
13
15
D
4
3
7
C
2
2
4
B
3
0
3
Start
0
0
0
A
2
2
0
LF = Min(LS of following activity)
10
13
*
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LS/LF Times for
Milwaukee Paper
E
4
F
3
G
5
H
2
4
8
13
15
4
8
13
7
13
15
10
13
8
13
4
8
D
4
3
7
C
2
2
4
B
3
0
3
Start
0
0
0
A
2
2
0
LF = Min(4, 10)
4
2
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LS/LF Times for
Milwaukee Paper
E
4
F
3
G
5
H
2
4
8
13
15
4
8
13
7
13
15
10
13
8
13
4
8
D
4
3
7
C
2
2
4
B
3
0
3
Start
0
0
0
A
2
2
0
4
2
8
4
2
0
4
1
0
0
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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
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Computing Slack Time
| TABLE 3.3 | Milwaukee Paper’s Schedule and Slack Times | |||||
| ACTIVITY | EARLIEST START ES | EARLIEST FINISH EF | LATEST START LS | LATEST FINISH LF | SLACK LS – ES | ON CRITICAL PATH |
| A | 0 | 2 | 0 | 2 | 0 | Yes |
| B | 0 | 3 | 1 | 4 | 1 | No |
| C | 2 | 4 | 2 | 4 | 0 | Yes |
| D | 3 | 7 | 4 | 8 | 1 | No |
| E | 4 | 8 | 4 | 8 | 0 | Yes |
| F | 4 | 7 | 10 | 13 | 6 | No |
| G | 8 | 13 | 8 | 13 | 0 | Yes |
| H | 13 | 15 | 13 | 15 | 0 | Yes |
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Critical Path for
Milwaukee Paper
E
4
F
3
G
5
H
2
4
8
13
15
4
8
13
7
13
15
10
13
8
13
4
8
D
4
3
7
C
2
2
4
B
3
0
3
Start
0
0
0
A
2
2
0
4
2
8
4
2
0
4
1
0
0
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© 2014 Pearson Education, Inc.
ES – EF Gantt Chart
for Milwaukee Paper
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
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
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LS – LF Gantt Chart
for Milwaukee Paper
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
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
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CPM assumes we know a fixed time estimate for each activity and there is no variability in activity times
PERT uses a probability distribution for activity times to allow for variability
Variability in Activity Times
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Three time estimates are required
Optimistic time (a) – if everything goes according to plan
Pessimistic time (b) – assuming very
unfavorable conditions
Most likely time (m) – most realistic estimate
Variability in Activity Times
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Estimate follows beta distribution
Variability in Activity Times
Expected time:
Variance of times:
t = (a + 4m + b)/6
v = [(b – a)/6]2
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Estimate follows beta distribution
Variability in Activity Times
Expected time:
Variance of times:
t = (a + 4m + b)/6
v = [(b − a)/6]2
Figure 3.11
Probability of 1 in 100 of
< a occurring
Probability of 1 in 100 of > b occurring
Probability
Optimistic Time (a)
Most Likely Time (m)
Pessimistic Time (b)
Activity Time
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Computing Variance
| TABLE 3.4 | Time Estimates (in weeks) for Milwaukee Paper’s Project | ||||
| ACTIVITY | OPTIMISTIC a | MOST LIKELY m | PESSIMISTIC b | EXPECTED TIME t = (a + 4m + b)/6 | VARIANCE [(b – a)/6]2 |
| A | 1 | 2 | 3 | 2 | .11 |
| B | 2 | 3 | 4 | 3 | .11 |
| C | 1 | 2 | 3 | 2 | .11 |
| D | 2 | 4 | 6 | 4 | .44 |
| E | 1 | 4 | 7 | 4 | 1.00 |
| F | 1 | 2 | 9 | 3 | 1.78 |
| G | 3 | 4 | 11 | 5 | 1.78 |
| H | 1 | 2 | 3 | 2 | .11 |
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Probability of Project Completion
Project variance is computed by summing the variances of critical activities
s2 = Project variance
= (variances of activities
on critical path)
p
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© 2014 Pearson Education, Inc.
Probability of Project Completion
Project variance is computed by summing the variances of critical activities
Project variance
s2 = .11 + .11 + 1.00 + 1.78 + .11 = 3.11
Project standard deviation
sp = Project variance
= 3.11 = 1.76 weeks
p
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Probability of Project Completion
PERT makes two more assumptions:
- Total project completion times follow a normal probability distribution
- Activity times are statistically independent
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Probability of Project Completion
Standard deviation = 1.76 weeks
Figure 3.12
15 Weeks
(Expected Completion Time)
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Probability of Project Completion
What is the probability this project can be completed on or before the 16 week deadline?
Where Z is the number of standard deviations the due date or target date lies from the mean or expected date
Z = – /sp
= (16 weeks – 15 weeks)/1.76
= 0.57
Due Expected date
date of completion
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© 2014 Pearson Education, Inc.
Probability of Project Completion
What is the probability this project can be completed on or before the 16 week deadline?
Where Z is the number of standard deviations the due date or target date lies from the mean or expected date
Z = − /sp
= (16 wks − 15 wks)/1.76
= 0.57
due expected date
date of completion
.00 .01 .07 .08
.1 .50000 .50399 .52790 .53188
.2 .53983 .54380 .56749 .57142
.5 .69146 .69497 .71566 .71904
.6 .72575 .72907 .74857 .75175
From Appendix I
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Probability of Project Completion
Figure 3.13
Time
Probability
(T ≤ 16 weeks)
is 71.57%
0.57 Standard deviations
15 16
Weeks Weeks
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© 2014 Pearson Education, Inc.
Determining Project Completion Time
Figure 3.14
Probability of 0.01
Z
From Appendix I
Probability of 0.99
2.33 Standard deviations
0
2.33
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Variability of Completion Time for Noncritical Paths
Variability of times for activities on noncritical paths must be considered when finding the probability of finishing in a specified time
Variation in noncritical activity may cause change in critical path
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What Project Management Has Provided So Far
The project’s expected completion time is 15 weeks
There is a 71.57% chance the equipment will be in place by the 16 week deadline
Five activities (A, C, E, G, and H) are on the critical path
Three activities (B, D, F) are not on the critical path and have slack time
A detailed schedule is available
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© 2014 Pearson Education, Inc.
Cost–Time Trade-Offs and Project Crashing
It is not uncommon to face the following situations:
- The project is behind schedule
- The completion time has been moved forward
Shortening the duration of the project is called project crashing
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© 2014 Pearson Education, Inc.
Factors to Consider When Crashing a Project
The amount by which an activity is crashed is, in fact, permissible
Taken together, the shortened activity durations will enable us to finish the project by the due date
The total cost of crashing is as small as possible
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© 2014 Pearson Education, Inc.
Steps in Project Crashing
- Using current activity times, find the critical path and identify the critical activities
(Crash cost – Normal cost)
(Normal time – Crash time)
Crash cost
per period
=
- Compute the crash cost per time period. If crash costs are linear over time:
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© 2014 Pearson Education, Inc.
Steps in Project Crashing
If there is only one critical path, then select the activity on this critical path that (a) can still be crashed, and (b) has the smallest crash cost per period. If there is more than one critical path, then select one activity from each critical path such that (a) each selected activity can still be crashed, and (b) the total crash cost of all selected activities is the smallest. Note that the same activity may be common to more than one critical path.
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© 2014 Pearson Education, Inc.
Steps in Project Crashing
Update all activity times. If the desired due date has been reached, stop. If not, return to Step 2.
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© 2014 Pearson Education, Inc.
Crashing The Project
| TABLE 3.5 | Normal and Crash Data for Milwaukee Paper Manufacturing | |||||
| ACTIVITY | TIME (WEEKS) | COST ($) | CRASH COST PER WEEK ($) | CRITICAL PATH ? | ||
| NORMAL | CRASH | NORMAL | CRASH | |||
| A | 2 | 1 | 22,000 | 22,750 | 750 | Yes |
| B | 3 | 1 | 30,000 | 34,000 | 2,000 | No |
| C | 2 | 1 | 26,000 | 27,000 | 1,000 | Yes |
| D | 4 | 2 | 48,000 | 49,000 | 1,000 | No |
| E | 4 | 2 | 56,000 | 58,000 | 1,000 | Yes |
| F | 3 | 2 | 30,000 | 30,500 | 500 | No |
| G | 5 | 2 | 80,000 | 84,500 | 1,500 | Yes |
| H | 2 | 1 | 16,000 | 19,000 | 3,000 | Yes |
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© 2014 Pearson Education, Inc.
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Crash and Normal Times and Costs for Activity B
Figure 3.15
| | |
1 2 3 Time (Weeks)
$34,000 —
$33,000 —
$32,000 —
$31,000 —
$30,000 —
—
Activity Cost
Crash
Normal
Crash Cost
Normal Cost
Crash Time
Normal Time
Crash Cost/Wk =
Crash Cost – Normal Cost
Normal Time – Crash Time
=
$34,000 – $30,000
3 – 1
= = $2,000/Week
$4,000
2 Wks
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© 2014 Pearson Education, Inc.
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Critical Path and Slack Times for Milwaukee Paper
Figure 3.16
E
4
F
3
G
5
H
2
4
8
13
15
4
8
13
7
13
15
10
13
8
13
4
8
D
4
3
7
C
2
2
4
B
3
0
3
Start
0
0
0
A
2
2
0
4
2
8
4
2
0
4
1
0
0
Slack = 1
Slack = 1
Slack = 0
Slack = 6
Slack = 0
Slack = 0
Slack = 0
Slack = 0
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© 2014 Pearson Education, Inc.
Advantages of PERT/CPM
Especially useful when scheduling and controlling large projects
Straightforward concept and not mathematically complex
Graphical networks help highlight relationships among project activities
Critical path and slack time analyses help pinpoint activities that need to be closely watched
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© 2014 Pearson Education, Inc.
Advantages of PERT/CPM
Project documentation and graphics point out who is responsible for various activities
Applicable to a wide variety of projects
Useful in monitoring not only schedules but costs as well
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© 2014 Pearson Education, Inc.
Project activities have to be clearly defined, independent, and stable in their relationships
Precedence relationships must be specified and networked together
Time estimates tend to be subjective and are subject to fudging by managers
There is an inherent danger of too much emphasis being placed on the longest, or critical, path
Limitations of PERT/CPM
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© 2014 Pearson Education, Inc.
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Using Microsoft Project
Program 3.1
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© 2014 Pearson Education, Inc.
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Using Microsoft Project
Program 3.2
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© 2014 Pearson Education, Inc.
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Using Microsoft Project
Program 3.3
| Pollution Project Percentage Completed on Aug. 12 | |
| ACTIVITY | COMPLETED |
| A | 100 |
| B | 100 |
| C | 100 |
| D | 10 |
| E | 20 |
| F | 20 |
| G | 0 |
| H | 0 |
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© 2014 Pearson Education, Inc.
All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of the publisher.
Printed in the United States of America.
