8-1 Scheduling Scheduling Defined Gantt Charts Network Techniques: PERT and CPM Determining Task...

8-1

Scheduling Scheduling Defined Gantt Charts Network Techniques: PERT and

CPM Determining Task Durations

Probability and Simulation Some Examples

8-2

Scheduling Defined The conversion of a project action

plan into an operating timetable Serves as the basis for monitoring

and controlling the project A major tool for the management of

projects

8-3

Some Benefits of Successful Scheduling Illustrates interdependence of all tasks Identifies times when resources must be

available Facilitates communication throughout

the project Determines critical activities/critical

path Affects client expectations through

establishment of activities, milestones, and completion dates

8-4

A Process for Scheduling 1. Think 2. List activities 3. Arrange activities considering

precedence and relationships 4. Develop Gantt charts and PERT/CPM

networks 5. Determine critical activities/critical

path 6. Crash and adjust as necessary

8-5

Gantt Charts

Advantages Easy to understand Easy to show progress and status Easy to maintain Most popular view to communicate project status

to client and/or senior management Disadvantages

Can be superficial Not always easy to see precedence, relationships

JAN FEB MAR

1 8 15 22 29 5 12 19 26 5 12 19 26

8-6

PERT/CPM Network Charts

Advantages Allows visualization of task relationships Facilitates calculation of critical path Clarifies impact of decisions on downstream

activities Disadvantages

Complex, not easy to comprehend at a glance Charts don’t readily depict durations, dates, progress

8-7

Look at a Simple Network, for a Simple Project

Activity

A

B

C

D

E

F

Duration (weeks)

14

3

3

7

4

10

Predecessor

Start

Start

A,B

B

C,D

E

8-8

A Simple Network (AON) (cont’d)

Start

A 14 C 3

E 4 F 10

B 3 D 7 Finish

Calculate:

Critical Path

Project Duration

8-9

The Critical Path

Start

A 14 C 3

E 4 F 10

B 3 D 7 Finish

ES = 0EF = 14

ES = 14EF = 17

ES = 17EF = 21

ES = 21EF = 31

ES = 0EF = 3

ES = 3EF = 10

= Critical Path

8-10

Determining Slack How much slack is there Where is it? How do you know? Why might you care?

8-11

Determining Slack (cont’d)

Start

A 14 C 3

E 4 F 10

B 3 D 7 Finish

ES = 0EF = 14LS = 0LF = 14

ES = 14EF = 17LS = 14LF = 17

ES = 17EF = 21LS = 17LF = 21

ES = 21EF = 31LS = 21LF = 31

ES = 0EF = 3LS = 7LF = 10

ES = 3EF = 10LS = 10LF = 17

Work Back . . .

8-12

Determining Slack (cont’d)

Start

A 14 C 3

E 4 F 10

B 3 D 7 Finish

ES = 0EF = 14LS = 0LF = 14

ES = 14EF = 17LS = 14LF = 17

ES = 17EF = 21LS = 17LF = 21

ES = 21EF = 31LS = 21LF = 31

ES = 0EF = 3LS = 7LF = 10

ES = 3EF = 10LS = 10LF = 17 Slack = LS - ES

CP = 0 Slack, where ES = LS

What does all this mean?

8-13

Three Sequential Activities, AON Format

8-14

Activity Network, AON Format

8-15

Activity Network, AOA Format

8-16

Sample of Network Construction, Figure 8-5

AONAON AOAAOA

8-17

Sample of Network Construction, Figure 8-6

AONAON AOAAOA

8-18

Sample of Network Construction, Figure 8-7

AONAON AOAAOA

8-19

Networking Concurrent Activities, Figure 8-8

8-20

Activity c Not Required for e, Figure 8-9

8-21

Showing Precedents, Figure8-10

8-22

MSP Gantt Chart, Figure 8-11

8-23

MSP AON Network, Figure8-12

8-24

An AON Network for a 10-Activity Project, Figure 8-13

8-25

Distribution of Possible Activity Times, Figure 8-14

8-26

AON Network with Durations and Variances, Figure 8-15

8-27

AON Network with Earliest/Latest Start/Finish Times, Figure 8-16

8-28

Gantt Chart of Table 8-4, Figure 8-17

8-29

AON Network of Table 8-4, Figure 8-18

8-30

MSP Gantt Chart of Table 8-4, Figure 8-19

8-31

MSP Gantt Chart, Video Project, Figure 8-20

8-32

MSP AON Network, Video Project, Figure 8-21

8-33

MSP Calendar, Video Project, Figure 8-22

8-34

MSP Calendar, Video Project, Figure 8-22 (continued)

8-35

MSP Gantt Chart, Video Project, Figure 8-23

8-36

Probability Distribution,Figure 8-24

8-37

a, m, and b Estimates,Figure 8-25

8-38

Crystal Ball® 2000 Spreadsheet, Figure 8-26

8-39

CB Frequency Chart, Figure 8-27

8-40

CB Summary Statistics,Figure 8-28

8-41

CB Percentile Probabilities, Figure 8-29

8-42

CB Cumulative Probability Chart, Figure 8-30

8-43

Precedence Diagramming Conventions, Figure 8-31

8-44

Sample GERT Network,Figure 8-33

8-45

Apartment Complex Network, Figure 8-35