Project Management

LectureNetwork Analysis

Introduction Project planning

Gantt chart and WBS

Project planning Network analysis I

Project planning Network analysis II

Project planning Network analysis I

Project planning Network analysis II

Plan Project planning

Resource analysis Risk management Quality Budgets and cost

control Project teams

Why Network Diagrams? Splits up the decision making process

into Method/logic - the order in which tasks

have to be completed Time – estimates for the time to

completion can be added to each task Resources – these can be added and then

analysis carried out

Project Exercise 1Project 1: Verification of a computer systemThe followng table shows the activities required for this project.

Activity ID Activity Immediate Predecessor

Duration (Days)

1 Test Module A none 42 Test Module B Test Module A 63 Test Module C none 74 Test Combined Modules Test Module B, Test Module C 45 Check User Documents Test Combined Modules 56 Print User Documents Check User Documents 27 Final Systems Check Test Combined Modules 98 Prepare Invoice Final Systems Check 19 Ship to Customer Print User Documents, Final

Systems Check2

Project Exercise 1

4

1. Test Module A

6

2. Test Module B

7

3. Test Module C

4

4. Test CombinedModules

5

5. Check UserDocuments

9

7. Final SystemCheck

2

6. Print UserDocuments

2

9. Ship toCustomer

1

8. Prepareinvoice

Why Network Diagrams? Splits up the decision making process

into Method/logic - the order in which tasks

have to be completed Time – estimates for the time to

completion can be added to each task Resources – these can be added and then

analysis carried out

Two Parts to the Analysis Forward Pass

Calculates the Duration of the Project Backward Pass

Calculates the slack/float for each task and shows the critical path

Forward Pass

(BBC, 2005)

In a game of rugby it is a means of cheating often missed by referees

Forward Pass …but in project management it is used To calculate the total duration of the

Project…

For each task: Take the earliest start time (EST) Calculate the Earliest finish time (EFT):

EFT = EST+Duration

What’s in the box?

Earliest Start

Estimated Duration

Earliest Finish

Activity NumberActivity Description

Latest Start

FloatLatest Finish

Earliest Start

Estimated Duration

Earliest Finish

Activity NumberActivity Description

Latest Start

FloatLatest Finish

Earliest Start

Estimated Duration

Earliest Finish

Activity NumberActivity Description

Latest Start

FloatLatest Finish

Forward Pass

Task A

27 0

Task B

5

Task C

10

Task A

27 27 0

Task B

5

Task C

10

Task A

27 27 0

Task B

5 27

Task C

10 27

Task A

27 27 0

Task B

32 5 27

Task C

37 10 27

Task A

27 27 0

Task C

?? 5 ??

Task B

22 12 10

Task A

27 27 0

Task C

5 27

Task B

22 12 10

Task A

27 27 0

Task C

32 5 27

Task B

22 12 10

Forward Pass

Project Exercise 1Project 1: Verification of a computer systemThe followng table shows the activities required for this project.

Activity ID Activity Immediate Predecessor

Duration (Days)

1 Test Module A none 42 Test Module B Test Module A 63 Test Module C none 74 Test Combined Modules Test Module B, Test Module C 45 Check User Documents Test Combined Modules 56 Print User Documents Check User Documents 27 Final Systems Check Test Combined Modules 98 Prepare Invoice Final Systems Check 19 Ship to Customer Print User Documents, Final

Systems Check2

Exercise 1 – Forward Pass Carry out a forward

pass on Project in Exercise 1

Project Exercise 1

4

1. Test Module A

6

2. Test Module B

7

3. Test Module C

4

4. Test CombinedModules

5

5. Check UserDocuments

9

7. Final SystemCheck

2

6. Print UserDocuments

2

9. Ship toCustomer

1

8. Prepareinvoice

Project Exercise 1

0 4 4

1. Test Module A

4 6 10

2. Test Module B

0 7 7

3. Test Module C

10 4 14

4. Test CombinedModules

14 5 19

5. Check UserDocuments

14 9 23

7. Final SystemCheck

19 2 21

6. Print UserDocuments

23 2 25

9. Ship toCustomer

23 1 24

8. Prepareinvoice

Dangler

Dangler

Dangler

Start and Finish Nodes

0 4 4

1. Test Module A

4 6 10

2. Test Module B

0 7 7

3. Test Module C

10 4 14

4. Test CombinedModules

14 5 19

5. Check UserDocuments

14 9 23

7. Final SystemCheck

19 2 21

6. Print UserDocuments

23 2 25

9. Ship toCustomer

23 1 24

8. Prepareinvoice

0 0 0

Start

25 0 25

Finish

What’s in the box?

Earliest Start

Estimated Duration

Earliest Finish

Activity NumberActivity Description

Latest Start

FloatLatest Finish

Earliest Start

Estimated Duration

Earliest Finish

Activity NumberActivity Description

Latest Start

FloatLatest Finish

Earliest Start

Estimated Duration

Earliest Finish

Activity NumberActivity Description

Latest Start

FloatLatest Finish

Backward Pass To calculate the float for each task?

For each task: Take the latest start time (LST) Calculate the latest finish time (LFT):

LST = LFT-Duration

Backward Pass

Task A

27 27 0

Task C

32 5 27

Task B

22 12 10

Task A

27 27 0

Task C

32 5 27

32

Task B

22 12 10

Task A

27 27 0

Task C

32 5 27

32 27

Task B

22 12 10

Task A

27 27 0

27

Task C

32 5 27

32 27

Task B

22 12 10

27

Task A

27 27 0

27 0

Task C

32 5 27

32 27

Task B

22 12 10

27 15

Backward Pass

Task A

34 7 27

Task B

41 7 34

48

Task C

43 9 34

45

Task A

34 7 27

Task B

41 7 34

48 41

Task C

43 9 34

45 36

Task A

34 7 27

36 29

Task B

41 7 34

48 41

Task C

43 9 34

45 36

Project Exercise 1Project 1: Verification of a computer systemThe followng table shows the activities required for this project.

Activity ID Activity Immediate Predecessor

Duration (Days)

1 Test Module A none 42 Test Module B Test Module A 63 Test Module C none 74 Test Combined Modules Test Module B, Test Module C 45 Check User Documents Test Combined Modules 56 Print User Documents Check User Documents 27 Final Systems Check Test Combined Modules 98 Prepare Invoice Final Systems Check 19 Ship to Customer Print User Documents, Final

Systems Check2

Exercise 1 – Backward Pass Carry out a backward pass on project

exercise 1

Ex1 - After Backward Pass

0 4 4

0 4

1. Test Module A

4 6 10

4 10

2. Test Module B

0 7 7

3 10

3. Test Module C

10 4 14

10 14

4. Test CombinedModules

14 5 19

15 21

5. Check UserDocuments

14 9 23

14 23

7. Final SystemCheck

19 2 21

21 23

6. Print UserDocuments

23 2 25

23 25

9. Ship toCustomer

23 1 24

24 25

8. Prepareinvoice

0 0 0

0 0

Start

25 0 25

25 25

Finish

What about the float? Float = LFT-EFT

Or Float = LST-EST

What about the float? Float represents the amount of time

that the task can be delayed without affecting the outcome of the project

A task with zero float cannot be delayed and is therefore critical to the timely completion of the project

What about the float? A time optimised project will have a

sequence of tasks from start to finish that have zero float

This sequence of tasks is called the critical path

Project Exercise 1Project 1: Verification of a computer systemThe followng table shows the activities required for this project.

Activity ID Activity Immediate Predecessor

Duration (Days)

1 Test Module A none 42 Test Module B Test Module A 63 Test Module C none 74 Test Combined Modules Test Module B, Test Module C 45 Check User Documents Test Combined Modules 56 Print User Documents Check User Documents 27 Final Systems Check Test Combined Modules 98 Prepare Invoice Final Systems Check 19 Ship to Customer Print User Documents, Final

Systems Check2

Exercise 1 – Critical Path Calculate the float for each task and

identify the critical path through the project

Ex1 – Float

0 4 4

0 0 4

1. Test Module A

4 6 10

4 0 10

2. Test Module B

0 7 7

3 3 10

3. Test Module C

10 4 14

10 0 14

4. Test CombinedModules

14 5 19

15 2 21

5. Check UserDocuments

14 9 23

14 0 23

7. Final SystemCheck

19 2 21

21 2 23

6. Print UserDocuments

23 2 25

23 0 25

9. Ship toCustomer

23 1 24

24 1 25

8. Prepareinvoice

0 0 0

0 0 0

Start

25 0 25

25 0 25

Finish

Ex1 – Critical Path

0 4 4

0 0 4

1. Test Module A

4 6 10

4 0 10

2. Test Module B

0 7 7

3 3 10

3. Test Module C

10 4 14

10 0 14

4. Test CombinedModules

14 5 19

15 2 21

5. Check UserDocuments

14 9 23

14 0 23

7. Final SystemCheck

19 2 21

21 2 23

6. Print UserDocuments

23 2 25

23 0 25

9. Ship toCustomer

23 1 24

24 1 25

8. Prepareinvoice

0 0 0

0 0 0

Start

25 0 25

25 0 25

Finish

Questions My Project has no critical path. What

does this mean?

My programmer has broken his big toe in a skiing accident and cannot type for two weeks (he has a valid sick note). How will this affect my software delivery date?

Directed Study Find the critical path for Project

Exercise 2 (see Lecture 3).

Find the critical path for the large project in Exercise 3.

Introduction Project planning

Gantt chart and WBS

Project planning Network analysis I

Project planning Network analysis II

Project planning Network analysis I

Project planning Network analysis II

Plan Project planning

Resource analysis Risk management Quality Budgets and cost

control Project teams

Project planning Resource analysis

Risk management Quality Budgets and cost

control Project teams