Project Management
What is a project?
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

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Unique, one-time operations designed to accomplish a set of objectives in a limited time
frame
Examples: construction of new buildings, installing a new computer network system,
launching a space shuttle, producing a movie, etc
Once underway, projects must be monitored to contain cost and meet timelines
This chapter is devoted to a description of graphical and computational methods that
are used for planning and scheduling projects
Key Decisions in Project Management
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Deciding which projects to implement
Selecting the project manager
Selecting the project team
Planning and deciding the project
Managing and controlling project resources
Deciding if and when a project should be terminated
Planning and Scheduling With Gantt Charts
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Gantt chart - a popular tool for planning and scheduling simple projects
Used to monitor progress over time by comparing planned progress to actual progress
Planning with PERT/CPM
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PERT (program evaluation review technique) and CPM (critical path method) are two of the
most widely used techniques for planning and coordinating large-scale projects

By using PERT/CPM, managers are able to obtain:
(a) A graphical display of project activities
(b) An estimate of how long the project will take
(c) An indication of which activities are most critical to timely project completion
(d) An indication of how long an activity can be delayed without lengthening the project

Network Diagram – a.k.a. precedence diagram is a chart used in PERT that depicts
major project activities and their sequential relationships
o Activity on Node (AON)
o Activity on Arrow (AOA)
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Path – a sequence of activities that leads from the starting node to the finishing nodes
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Critical path – the path with the longest time
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Critical activities – activities that are on the critical path. They have zero slack
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Network conventions
a
b
c
a
c
b
b
a
c
a
c
b
d
a
c
a
c
b
d
b
Deterministic vs Probabilistic Time Estimates

Deterministic times – if time estimates can be made with a high degree of confidence
that actual time will not differ significantly
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Probabilistic times – must include an indication of the extent of probable variation
te 
t0  4tm  t p
2 
6
(t p  to ) 2
36
A Computing Algorithm
ES – earliest time activity can start
EF – earliest time an activity can finish
LS – latest time an activity can start
LF – latest time an activity can finish
EF = ES + t
ES
EF
ES
t
LS = LF - t
LS
LF
LS
t
LS
LF
LS
ES
EF
ES
t
Problem 1 (see page 806)
Problem 3 (768)
The information below pertains to a project that is about to commence. As the project manager, which
activities would you be concerned with in terms of timely project completion? Explain.
Immediate
Estimated
Estimated
Activity
Predecessor
Time (days)
Activity
Precedes
Time (days)
a
--
15
a
B
15
b
A
12
b
C,D
12
c
B
6
c
E
6
d
B
5
d
End
5
e
C
3
e
End
3
f
--
8
f
G,H
8
g
F
8
g
I
8
h
F
9
h
J
9
i
G
7
i
End
7
j
H
14
j
K
14
k
J
6
k
End
6
End
D,E,I,K
Problem 7 (769)
Three recent college graduates have formed a partnership and have opened an advertising firm. The first
project consists of activities in the following table.
Activity
A
B
C
D
E
F
G
H
I
End
Immediate
Predecessor
--A
-C
D
F
B
H
E,G,I
to
5
8
6
9
5
5
2
4
5
tm
6
8
8
12
6
6
3
4
7
tp
7
11
11
15
9
7
7
5
8
(a) Draw the precedence diagram
(b) What is the probability that the project can be completed in 24 days or less? In 21 days or less?
Excel Solution
(c)
Suppose it is now the end of the seventh day and that activities A and B have been completed. Time
estimates for the completion of activity D are 5, 6, and 7. Activity C and H are ready to begin. Determine the
probability of finishing the project by day 24 and the probability of finishing by day 21.
Problem 11(770)
The following precedence diagram reflects three time estimates for each activity. Determine:
9-10-12
(e)
8
3
8-10-14
(i)
11-12-13
(b)
5-6-7
(c)
8-8-8
(a)
1
14-18-26
(f)
6
11
.5
13-15
10.5(j)
13-13-13
(g)
4
2
5-7-10
(k)
6-6-6
(m)
7
11-12-14
(d)
10
5
7-10-12
(h)
9
10-11-12
(l)
(a) The expected completion time for each path and its variance
(b) The probability that the project will require more than 49 weeks.
(c) The probability that the project can be completed in 46 weeks or less.