1. Project Scheduling
Chapter 14

2. Outline What is a “project”? Objectives and tradeoffs
Planning and Control in Projects
Scheduling Methods
Constant-Time Networks
Precedence Diagramming Method
PERT and CPM Methods
Use of Project Concepts

3. What is a “Project”? Distinguishing characteristics of projects
Example

4. Examples of Projects (Table 14.1)

5. Objectives and Tradeoffs
Stay within
the budget
Meet the
deadline
Due Date!
Meet the
specifications

6. Project Management Activities and Decisions
Planning
Scheduling
Project
Control

7. Planning Identify the project customer
Establish the end product or service
Set project objectives
Estimate total resources and time required
Decide on the form of project organization
Make key personnel appointments
Define major tasks required
Establish a budget

8. Scheduling Develop a detailed work-breakdown structure
Estimated time required for each task
Sequence tasks in proper order
Develop a start/stop time for each task
Develop detailed budget for each task
Assign people to tasks

9. Control Monitor actual time, cost, and performance
Compare planned to actual figures
Determine whether corrective action is needed
Evaluate alternative corrective actions
Take appropriate corrective action

10. Gantt Chart Project Example (Figure 14.1)
Week

11. Network Project Chart (Figure 14.2)7
Secure outside
sheathing 1 2 3 5 6
Dig
basement
Pour
footing
Lay block
foundation
Install main
floor
Erect
frame 8
Install roof
boards
Finish
rough-in
frame
Start 4 10
Finish below-
grade work 9
Install windows

12. Constant-Time Networks
Activity times assumed to be constant
“Dummy” activities
Notations used in calculating start and finish times:
ES(a) = Early Start of activity a
EF(a) = Early Finish of activity a
LS(a) = Late Start of activity a
LF(a) = Late Finish of activity a

13. Network Diagram (Figure 14.3)2 5 3 1 4 2 4 6 3 1
Event
Activity

14. Dummy Activity Situations (Figure 14.4a)H G
a. Activities F and G have
the same predecessor (E)
and the same successor (H)

15. Dummy Activity Situations (Figure 14.4b)
b. Activity A and B have a common
predecessor (E), but they have different
predecessors (C and D)

16. Dummy Activity Situations (Figure 14.4c)K D J
c. Activities C and D have a
common successor (K), but
different successors (I and J)

17. Calculating ES, EF, LS, LF, and Completion Time
Forward Pass:
ES (a) = 0 for the starting activity
EF (a) = ES (a) + t (a)*
ES (a) = max [EF (all predecessors of a)]
Project completion time = max [EF(all ending activities)]
Backward pass:
LF (a) = min [LS (all successors of a)]
LS (a) = LF - t(a)*
* t (a) denotes the duration of activity a

18. Slack Times Total Slack Time (TST): Free Slack Time (FST)
LS (a) - ES (a) - EF (a)= LF(a) - EF(a)
Free Slack Time (FST)
min [ES (all successors of a)] - EF (a)

19. Activity Start and Finish Times (Figure 14.5)2
[3, 8] 5
[0, 3] 3
[3, 8]
[0, 3] 1
[3, 5] 2 4
[4, 6]
[0, 4] 4
[5, 7] 2
[2, 6]
[6, 8] 3
[ES, EF]
[LS, LF]

20. Activity Times (Table 14.3)

21. PDM Network (Figure 14.6) Activity 1-2 Activity 2-4 Activity 2-3
1-3
Activity
3-4

22. PDM Time Schedule (Figure 14.7)
2-4
1-2
2-3
Project Completion
1-3
3-4 1 2 3 4 5 6 7 8

23. PDM Precedence RelationshipB
Start to Start
Job B can start no sooner than
2 days after Job A has started.
SS = 2 A B
Finish to Start
Job B can start no sooner than
3 days after Job A is completed.
FS = 3 A B
Start to Finish
Job B can finish no sooner than
6 days after Job A has started.
SF = 6 A B
Finish to Finish
Job B can finish no sooner than
4 days after Job A was finished.
FF = 4

24. Cement Floor Example (Figure 14.9)
SS = 1
Pour
cement
Install
forms
FF = 0

25. Time-Cost Relationship in CPM
Crash Cost
Cost
Normal Cost
Crash
Time
Normal
Time
Time

26. Use of Project Management Concepts
Scheduling is only part of a complete approach to project management
Tradeoffs between sophistication and cost of methods
Choice between PERT, CPM, and PDM
Project management software