1. ENGM91 ACTIVITY PLANNING Unit 2

2. Introduction 1 The unit will cover Also …..
Work breakdown structure (WBS)
Product breakdown Structure (PBS)
An introduction to system modelling
Precedence analysis
Gantt Charts
PERT / CPA
On Arrow Networks
Precedence Networks
Also …..
Microsoft Project will be covered in labs
This is based on Gantt Charts and Precedence Networks

3. Introduction 2 Activity Planning will help to:
ensure that the appropriate resources will be available precisely when required
avoid different activities competing for the same resource at the same time
produce a detailed schedule showing which staff carry out each activity
Produce a detailed plan against which actual achievement may be measured
produce a timed forecast
re-plan the project during its life to correct drift from a target

4. Work Breakdown Structure (WBS)
WBS is the decomposition of work into progressively smaller and smaller chunks of work.
The logical conclusion is when work cannot be usefully broken down any further for the tasks being undertaken

5. Work Breakdown Structure
Project
Conduct
Investigation
Produce
Report

6. Work Breakdown Structure
Top Level Project
Level 1 Conduct Investigation

7. Work Breakdown Structure
Conduct
Investigation
Conduct
interviews
Investigate
other systems
Analyse
requirements
Investigate
hardware

8. Work Breakdown Structure
Top Level Project
Level 1 Conduct Investigation
Level 2 Conduct Interviews

9. Work Breakdown Structure
Conduct
interviews
Managing
director
Finance
director
Stores
manager
Sales
manager

10. Work Breakdown Structure
Top Level Project
Level 1 Conduct Investigation
Level 2 Conduct Interviews
Level 3 Interview Managing Director

11. Work Breakdown Structure
Interview MD
Conduct
interview
Write and
review notes
Create data
flow diagrams
Review data
flow diagrams

12. Work Breakdown Structure
Top Level Project
Level 1 Conduct Investigation
Level 2 Conduct Interviews
Level 3 Interview Managing Director
Level 4 Conduct Interview

13. Product Breakdown Structure (PBS)
Similar to WBS
PBS is the break down of a product into it’s discrete components.
a PBS can be included as part of a WBS

14. Product Breakdown Structure (PBS)
An example pbs – taken from a US MIL handbook

15. System Modelling

16. System Modelling
IDEF0

17. IDEF0

18. WBS and PBS
WBS, PBS and system modelling will assist in an understanding of the project
WBS and PBS must be done to allow Precedence analysis to take place
WBS and PBS do not necessarily set the precedence of a project
Precedence within a project should be based on what is best for the timely and economic completion of the project

19. Precedence analysis
Must be done before an activity plan can be produced
Reviews the activities that are to be carried out
Decides what activities must be carried out before particular activity can start

20. Gantt Charts Developed by Henry Gantt, around 1917
Gantt charts are easy to use and produce
They are very useful for use on less complex projects
Commonly used due to there simplicity
Gantt charts are easily understood and easy to read

21. Gantt Charts

22. Gantt Charts Draw the following Gantt chart Tasks Precedence Time
a days
b days
c a 6 days
d b 2 days
e b 5 days
f c,d 8 days
Get students to draw the Gantt chart.

23. Gantt Charts

24. Network planning models
PERT
The Program Evaluation and Review Technique
Developed by:
US Navy with
BOOZ-Allen Hamilton and
Lockheed Corporation for the
Polaris missile/submarine project in 1958

25. Network planning models
CPM
Critical Path Method
Also know as CPA
Critical Path Analysis
Developed by
DuPont Inc in the
Late fifties early sixties to facilitate
building of complex process plant

26. Network planning models
PERT
developed for use on R&D projects
CPM
developed for use in construction projects
When developed the two techniques were very similar
Now there is virtually no difference between the two

27. Network planning models
A simple on arrow network model 1 2 3 4 5
Start
End a b c d e f g h

28. Terminology Activity Event
A specific task, uses resources takes time to complete
Event
The result of completing an activity
Events use no resources
They are instances in time, points on the network, conditions of a system that can be recognised

29. Terminology
Network
The combination or all activities (often drawn as lines) and events (often drawn as nodes at the beginning and end of each line) defines the project and the activity precedence relationship.
Arrow heads placed on the lines indicate the direction of flow. Before and an event can be realised all the activities that immediately precede it must be completed

30. Terminology Path Critical
The series of connected activities (or intermediate events) between any two events in a network
Critical
Activities, events, or paths, which, if delayed, will delay the completion of the project
A project’s critical path is understood to mean that sequence of critical activities (and critical events) that connect the project’s start event to its finish event

31. Terminology On Arrow Network diagram showing critical path in red 1 23 4 5 6
A=6
B=4
D=4
C=3
E=3
F=10
H=2
G=3

32. Network syntax Time moves from left to right
Nodes are numbered sequentially
A network may not contain loops
A network may not contain dangles
Precedents are the immediate preceding activities
Dummy activities can be used to indicate a particular precedence

33. Network syntax Time moves from left to right
Nodes are numbered sequentially 1 2 3 a b

34. Network syntax A network may not contain loops 1 2 3 4
This is not allowed a b c d

35. Network syntax A network may not contain dangles 1 2 3 4
This is not allowed a b c

36. Network syntax Precedents are the immediate preceding activities 1 2 3
Design
Build 4
Commission

37. Network syntax
Dummy activities can be used to indicate a particular precedence 1 2 3
Wrong 4
Right a b c

38. On Arrow Networks Draw the following as an on arrow network
Tasks Precedence Time
a days
b days
c a 6 days
d b 2 days
e b 5 days
f c,d 8 days

39. On Arrow Networks
How to start ….. 1 2 3
start a b

40. On Arrow Networks
What not to do 1 2 3
start a b 4 5 6 c d e

41. On Arrow Networks
A better way …… 1 2 3
start a b c d e

42. On Arrow Networks
It is then less confusing that c & d go to the same event … but what about e & f ? 1 2 3
start a b 4 5 6 c d e f

43. On Arrow Networks The completed on arrow network …. 1 2 3 start a b 45 c d e f
end

44. On Arrow Networks Another on arrow network to draw
Tasks Precedence Time
a weeks
b weeks
c a 3 weeks
d b 4 weeks
e b 3 weeks
f weeks
g e,f 3 weeks
h c,d 2 weeks

45. On Arrow Networks The network with activity times added 1 3 4 6 2 5
B=4
D=4
F=10
E=3
G=3
H=2

46. On Arrow Networks Each event circle can contain the information below
number
Earliest
date
Latest
Slack

47. Event numbers 1 2 3 4 5 6

48. Timed activities 1 2 3 4 5 6
A=6
B=4
D=4
C=3
E=3
F=10
H=2
G=3

49. Forward pass 1 2 3 4 5 6
A=6
B=4
D=4
C=3
E=3
F=10
H=2
G=3 9 10 13

50. Backward pass 1 2 3 4 5 6 A=6 B=4 D=4 C=3 E=3 F=10 H=2 G=3 9 10 13 119 10 13 11 8 7

51. Event, Slack and Activity Float1 2 3 4 5 6
A=6
B=4
D=4
C=3
E=3
F=10
H=2
G=3 9 10 13 11 8 7

52. The Complete On Arrow Network1 2 3 4 5 6
A=6
B=4
D=4
C=3
E=3
F=10
H=2
G=3 9 10 13 11 8 7

53. Precedence Networks Precedence network also known as Activity on Node
Becoming more common as it is used by many project planning software packages
Often preferred by project managers

54. Precedence Networks Syntax the same as for On Arrow networks
Except there are no dummy activities
Precedence networks must start with a start node and end with a end node

55. Precedence Networks A simple precedence network Start End a b d c e fg h

56. This is the same network drawn as an On Arrow network1 2 3 4 5
Start
End a b c d e f g h

57. Precedence Networks A simple precedence network Start End a b d c e fg h

58. Precedence Networks Draw the following as an Precedence network
Tasks Precedence Time
a days
b days
c a 6 days
d b 2 days
e b 5 days
f c,d 8 days

59. Precedence Networks The completed Precedence Network Start End a b d cf

60. The same network drawn as an On Arrow Network1 2 3
start a b 4 5 c d e f
end

61. Precedence Networks The completed Precedence Network Start End a b d cf

62. Precedence Networks Another on precedence network to draw
Tasks Precedence Time
a weeks
b weeks
c a 3 weeks
d b 4 weeks
e b 3 weeks
f weeks
g e,f 3 weeks
h c,d 2 weeks

63. Precedence Networks The completed Precedence Network Start End a b d cf h g

64. This is the same network drawn as an On Arrow network1 3 4 6 2 5
A=6
C=3
B=4
D=4
F=10
E=3
G=3
H=2

65. Precedence Networks The completed Precedence Network Start End a b d cf h g

66. Precedence Networks Adding more information to the node ES D EF LS FLF
Earliest
start
Duration
Finish
Latest
Start
Float
Description

67. Precedence Networks ES = latest (largest) EF of preceding activity
e.g. event may start at day zero - this actually means the end of day zero or the beginning of day one !!!
EF = activity ES + activity duration
LS = activity LF – activity duration
LF = earliest (smallest) LS of subsequent activities.
Float = LS – ES or LF – EF

68. 2 6 8 4 10
Description 8 4 12 10 2 14
Description 3 2 5 8 10
Description

69. 12 4 16 20
Description 8 4 12 10 2 14
Description 12 6 18 14 2 20
Description

70. Precedence Networks
Redraw the following with complete information in each node box
Tasks Precedence Time
a days
b days
c a 6 days
d b 2 days
e b 5 days
f c,d 8 days

71. Precedence Networks
Redraw the following with complete information in each node box
Tasks Precedence Time
a weeks
b weeks
c a 3 weeks
d b 4 weeks
e b 3 weeks
f weeks
g e,f 3 weeks
h c,d 2 weeks

72. Conclusion Activity Planning Precedence analysis On Arrow networks
Precedence networks

73. Exercise 1 Tasks Precedence Time a - 6 weeks b - 4 weeks c - 3 weeks
d a 4 weeks
e b 3 weeks
f b 2 weeks
g c 3 weeks
h d,e 2 weeks
i f 1 week
j g,i 2 weeks

74. Exercise 2 Tasks Precedence Time a - 3 weeks b - 5 weeks c a 7 weeks
d b 5 weeks
e c, d 6 weeks
f b 4 weeks
g b 8 weeks
h c, d 4 weeks
i e, f 3 weeks

75. Exercise 3 Tasks Precedence Time a - 2 weeks b - 4 weeks c - 3 weeks
d a 3 weeks
e a 5 weeks
f c 6 weeks
g c 4 weeks
h d 4 weeks
i d 8 week
j b, e, f, i 2 weeks
k weeks
l g, k 3 weeks

76. Exercise 4 Tasks Precedence Time a - 3 weeks b a 5 weeks c a 3 weeks
d c 1 weeks
e b 3 weeks
f b, d 4 weeks
g c 2 weeks
h g, f 3 weeks
i e, h 1 weeks

77. Exercise 5 Tasks Precedence Time a - 3 weeks b - 5 weeks c a 14 weeks
d a 5 weeks
e b 4 weeks
f b 7 weeks
g d, e 8 weeks
h g, f 5 weeks