Transcript No Slide Title

Project Management: A Managerial
Approach
Chapter 8
Scheduling
Overview
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WBS to Schedule Process
PERT
Schedule Types
CPM
Scheduling
• A schedule is the conversion of a project
action plan into an operating timetable
• It serves as the basis for monitoring and
controlling project activity
• Taken together with the plan and budget,
it is probably the major tool for the
management of projects
Scheduling
• In a project environment, the
scheduling function is more important
than it would be in an ongoing
operation
• Projects lack the continuity of day-today operations and often present much
more complex problems of
coordination
Chapter 8-2
Scheduling
• The basic approach of all scheduling
techniques is to form a network of
activity and event relationships
• This network should graphically
portray the sequential relations
between the tasks in a project
• Tasks that must precede or follow
other tasks are then clearly identified
in time as well as function
Chapter 8-3
Types of Scheduling
• Operation Scheduling: a type of scheduling that
assigns jobs to machines or workers to job. Operation
schedule is crucial because many performance measures such as
on-time delivery, inventory levels, the manufacturing cycle
time, cost and quality, relate directly to the scheduling of
each production lot.
• Workforce Scheduling: a type of scheduling that
determine when employee work. Workforce scheduling is
equally crucial because measures of performance such as
customer waiting time, waiting-line length, utilization, cost,
and quality related to the availability of the servers
Chapter 8-2
Techniques of Scheduling
• Gantt Chart
• Network Techniques: PERT & CPM
Both of the techniques is called diagramed technique of
scheduling which possesses the following benefits:
– It is a consistent framework for planning,
scheduling, monitoring, and controlling the
project
– It illustrates the interdependence of all tasks, work
packages, and work elements
Chapter 8-2
Scheduling
• Network benefits (cont.):
– It aids in ensuring that the proper
communications take place between
departments and functions
– It determines an expected project completion
date
– It identifies so-called critical activities that, if
delayed, will delay the project completion
time
– It identifies activities with slack that can be
delayed for specific periods without penalty
Chapter 8-5
Scheduling
• Network benefits (cont.):
– It determines the dates on which tasks may be
started or must be started if the project is to stay
on schedule
– It illustrates which tasks must be coordinated to
avoid resource timing conflicts
– It illustrates which tasks may run, or must be
run, in parallel to achieve the predetermined
project completion date
– It relieves some interpersonal conflict by clearly
showing task dependencies
Chapter 8-6
Gantt chart
Advantages
Limitations
-Gantt charts are quite commonly used.
They provide an easy graphical
representation of when activities (might)
take place.
- Do not clearly indicate details regarding
the progress of activities
-Simple& quickest method.
- Do not give a clear indication of
interrelation ship between the separate
activities
Simple Schedule – Gantt Chart
Network Techniques: PERT and CPM
• With the exception of Gantt charts, the most
common approach to scheduling is the use
of network techniques such as PERT and
CPM
• The Program Evaluation and Review
Technique (PERT) was developed by the
U.S. Navy in 1958
• The Critical Path Method (CPM) was
developed by DuPont, Inc during the same
time period
Chapter 8-7
Network Techniques: PERT and CPM
• PERT has been primarily used for
research and development projects
• CPM was designed for construction
projects and has been generally
embraced by the construction industry
• The two methods are quite similar and
are often combined for educational
presentation
Chapter 8-8
Scheduling Terminology
• Activity - A specific task or set of tasks that are
required by the project, use up resources, and take
time to complete
• Event - The result of completing one or more
activities. An identifiable end state occurring at a
particular time. Events use no resources.
• Network - The combination of all activities and
events define the project and the activity
precedence relationships
Scheduling Terminology
• Path - 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 that
connect the project’s start event to its finish
event
Chapter 8-10
Scheduling Terminology
• An activity can be in any of these conditions:
– It may have a successor(s) but no predecessor(s) starts a network
– It may have a predecessor(s) but no successor(s) ends a network
– It may have both predecessor(s) and successor(s) in the middle of a network
Steps in CPM Scheduling
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1. Specify the individual activities.
2. Determine the sequence of those activities.
3. Draw a network diagram.
4. Estimate the completion time for each activity.
5. Identify the critical path (longest path
through the network)
• 6. Update the CPM diagram as the project
progresses.
Drawing Networks
• Activity-on-Arrow (AOA) networks use
arrows to represent activities while nodes
stand for events
• Activity-on-Node (AON) networks use
nodes to represent activities with arrows to
show precedence relationships
• The choice between AOA and AON
representation is largely a matter of
personal preference
Chapter 8-12
The Project Network
• Use of nodes and arrows
 An arrow leads from tail to
head directionally
– Indicate ACTIVITY, a time consuming effort
that is required to perform a part of the work.
Arrows
Nodes  A node is represented by a circle
- Indicate EVENT, a point in time where one or
more activities start and/or finish.
Activity on Node & Activity on Arrow
Activity on Node
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A completion of an
activity is represented by
a node
Activity on Arrow
- An arrow represents a
task, while a node is
the completion of a
task
- Arrows represent order
of events
Activity
Code
Activity
Duration in days
Depends on
A
Prepare Technical Specifications
10
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B
Tender Processing
25
A
C
Release of work order
3
B
D
Supply of Boiler equipment
60
C
E
Supply of Auxiliaries
20
C
F
Supply of pipes & pipe fittings
10
C
G
Civil Work
15
C
H
Installation of Auxiliary equipment &
piping
5
E,F&G
I
Installation of Boiler
10
D&H
J
Testing and commissioning
2
I
Requirements:
1. Draw a network diagram
2. Find out the critical Path.
Hypothetical Network
D
10
60
2
20 E
10
3
25
Start
C
B
A
10
6
15
F
5
5
5
G
I
H
J
End
End of the Lesson