CPM method. Following Slide will make you understand on network scheduling technique (CPM method)

1. USE OF NETWORK SCHEDULING TECHNIQUE (CPM) TO
SET UP A TEAM AND TO FABRICATE A FSAE CAR BY THE
TEAM
A report submitted in partial fulfillment of the
requirements for the course
of
OPERATIONS RESEARCH
by
BOLISETTI SIVA PRADEEP
09BEM080
SCHOOL OF MECHANICAL AND BUILDING SCIENCES
Vellore – 632014, Tamil Nadu, India
www. vit.ac.in
APRIL 2012
0

2. CONTENTS
Chapter No.
CHAPTER
1
Title
INTRODUCTION
Page No.
3
1.1 Introduction to network scheduling
1.2 Introduction to the team, objectives and
whole content of the project
CHAPTER
2
LITERATURE REVIEW
4
CHAPTER
3
METHODOLOGY
6
3.1
Problem Statements
3.2
Solutions
4
RESULTS AND DISCUSSION
4.1
Results and its significance
CHAPTER
4.2
CHAPTER
9
Advantages - Applications
5
CONCLUSIONS
10
REFERENCES
10
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3. 1. INTRODUCTION
1.1 INTRODUCTION TO NETWORK SCHEDULING
The complexities of the present day management problems and the business competitions
have added to the pressure on the brains of decision makers. In a large and complex project
involving a number of interrelated activities, requiring a number of men, machines and materials,
it is not possible for the management to make and execute an optimum schedule just by intuition
based on the organizational capabilities and work experience. Management are thus always on
the lookout for some methods and techniques which may help in planning, scheduling and
controlling the project. The aim of planning is to develop a sequence of activities of the project,
so that project completion time and cost are properly balanced and that the excessive demand of
key resources is avoided. CPM is one of the many network techniques which have been widely
used for planning, scheduling and controlling the large and complex projects.
The network technique which emphasizes more on activities is called CPM. CPM does
not take into account the uncertainties while estimating its activity times. The main difference
between CPM and PERT is PERT emphasizes more on events while CPM on activities.The
estimates in PERT are probabilistic while the times in CPM are relatively less uncertain and are
thus of deterministic in nature.
1.2 INTRODUCTION TO THE TEAM, OBJECTIVES AND WHOLE CONTENT OF
THE PROJECT
In V.I.T university we have many teams which make a car of their discipline to compete
in their corresponding event, for example BAJA. Team Pravega is one among them. Team
Pravega is a team which designs a small formula type race car. Each student team designs, builds
and tests a prototype based on a series of rules. The success of any team depends on the
commitment of its docile members, planning, scheduling and controlling the activities
efficiently, on contrary if planning, scheduling and controlling of the activities is not done
efficiently the team is vulnerable to failure. Construction of a FSAE car is a complex project
which involves many activities. These activities have to be planned, scheduled and controlled
properly so that project completion time and cost are properly balanced. The aim of my project is
to find out all the activities involved in design and fabrication of FSAE car by Team Pravega and
to draw the network and to apply network scheduling techniques like CPM for planning,
scheduling and controlling of this project and to finally find out the critical activities and critical
path.
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4. 2. LITERATURE REVIEW
N.K.Kwak et al in the year 2002 studied on critical path method and CRTI, a computerized CPM
program, as a tool for reporting and developing management information system Microbiology
Department of Deaconess Hospital to synchronize and coordinate the various tasks for efficient
management.
Edward L. Hanna et al in the year 2002 demonstrated on how goal programming can be used to
incorporate considerations other than project completion time and total project cost into the
typical CPM problem.
Lawrence Jones et al in the year 2002 dealt with application of CPM scheduling for the National
center for Drug Analysis. The model was constructed based on empirical data obtained at the
center for a five year period. It assists the management of the center in developing a complex
work planning process and in controlling the project tasks.
J.F.Barlow et al in the year 2003 studied on plotting of activity on node by computer using
output obtained from critical path analysis program. Three types of connections was allowed
between activities which are shown as boxes.
Yu Cheng et al in the year 2004 studied on optimal train traffic rescheduling simulation by
knowledge based system combined with critical path method for getting a nearly optimum
rescheduling under time and resource constraints. Global information concerning final
completion times of trains is used as a feedback function to control the delay and resolve the
resource conflict concerning current processing trains.
Shin Pin Chen et al in the year 2006 proposed an approach to critical path analysis for a project
network with activity times being fuzzy numbers, in that the membership function of the fuzzy
total duration time is constructed. The basic idea was based on the extension principle and linear
programming formulation. The total duration time is completely expressed by a membership
function.
Tarun Gupta et al in the year 2006 proposed an idea of applying CPM to continuous production
systems, and to implement the CPM not just at the outset but throughout the process. The
algorithm calls for repeatedly calculating the critical path through the production process and
routing parts so as to remain off the path.
Glenn R Dundas et al in the year 2006 studied on application of CPM for introducing an
industrial product. The paper suggests use of critical path method to ensure success at the
announcement/ introduction phase of the new product development.
R.A.Web et al in the year 2007 studied on application of critical path analysis to strawberry fruit
production from runner propagation to first harvest in an experimental situation. The analysis
indicated three phases of development.
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5. Yan Lie Chang et al in the year 2007 investigated on two types of time constraints commonly
encountered in project management. The first is the time window constraint and second is the
time schedule constraint. An efficient linear time algorithm for finding the critical path and for
analyzing the flow time of each arc was developed for activity networks with these time
constraints.
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6. 3.METHODOLOGY
3.1 PROBLEM STATMENTS
A list of all the activities involved and time taken for each activity has been found out by
interacting with the team members. A table showing list of all activities involved in fabricating a
FSAE car and the corresponding time take for each activity has been tabulated to draw the
network and to find out the critical activities and critical path by using CPM.
ACTIVITY
TASK INVOLVED
A
Setting up a productive team through rigorous selection
procedure involving written tests followed by interview
and presentation.
B
To get to know the first hand information about all the
departments in a car, for example suspension system etc.
C
Preparing a question paper for splitting the team into
corresponding departments.
D
Splitting the team into various departments based upon the
individual performance in the test and his field of interest.
E
Knowing the in-depth concepts by an individual
corresponding to his department and simultaneously
designing the components.
F
Selecting the event location.
G
Start of ordering the parts based on the calculations made
and receiving the parts.
H
Design of prototype by using software's.
I
Validating the final designs.
J
Fabricating the roll cage based on the designs made.
K
Machining the components which are to be custom made.
L
Assembly of all components.
M
Test run and troubleshooting.
Table 3.1 List of activities and their duration
5
No OF DAYS
7
10
3
5
40
7
60
25
5
30
50
20
10

7. 3.2 SOLUTIONS
For the above list of activities the precedence relationship has been found out, a network
involving all the activities has been dawn and finally the total length of the project, critical
activities and critical path has been found out using CPM.
PRECEDENCE RELATIONSHIP
A < B, C
B, C < D
D < E, F
E, F < G, H
G, H < I
I < J, K
J, K < L
L<M
NETWORK
Fig 3.1 Network involving all the activities
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8. REPRESENTATION IN TABULAR FORM
PREDESES
SOR
EVENT (i)
SUCCES
SOR
EVENT
(j)
ACTIVI
TY
DURATI
ON
tEij
1
2
2
3
4
5
5
6
7
7
8
9
10
10
11
12
13
2
3
4
4
5
6
7
7
8
9
9
10
11
12
12
13
14
7
3
10
0
5
7
40
0
60
25
0
5
30
50
0
20
10
EARLI
EST
START
TIME
Esi
EARLIES
T
COMPLE
TION
TIME
Ecij
0
7
7
10
7
17
10
10
17
22
22
29
22
62
29
29
62
122
62
87
122
122
122
127
127
150
127
177
157
157
177
197
197
207
Table 3.2
7
LATE
ST
STAR
T
TIME
Lsij
0
14
7
17
17
55
22
62
62
97
122
122
147
127
177
177
197
LATEST
COMPLE
TION
TIME
Lcj
7
17
17
17
22
62
62
62
122
122
122
127
177
177
177
197
207
FLO
AT
0
7
0
7
0
33
0
33
0
35
0
0
27
0
20
0
0

9. 4.RESULTS AND DISCUSSIONS
4.1 RESULTS AND ITS SIGNIFICANCE
The total length of the project was found out to be two hundred and seven days.
The critical activities were 1-2, 2-4, 4-5, 5-7, 7-8, 8-9, 9-10, 10-12, 12-13, 13-14.
The critical path is 1-2-4-5-7-8-9-10-12-13-14.
By applying CPM the total length of the project was found out to be two hundred seven days but
according to the previous year's team database the length of the project was three hundred and
thirty days. This increased length of the project can be attributed to the delay of critical activities,
as we know that the delay of critical activities leads to the delay of the entire project. The delay
of critical activities can further be attributed to scheduling of the university exams during the
project and non availability of the team members due to some reasons like health problems etc.
An example of delay in critical activity may be delay in receiving the ordered parts.
4.2 ADVANTAGES - APPLICATION
Finding out the critical activities and critical path assists the team in developing a complex work
planning process and in controlling the project tasks.
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10. 5. CONCLUSIONS
Thus the total length of the project, critical activities and critical path has been found out
by applying CPM technique in network scheduling. It has been found that the previous year's
total length of the project is exceeding the calculated total length of the project which may be
due to the delay in critical activities.
REFERENCES
1. D.S.HIRA, PREM KUMAR GUPTA (2008) Operations Research, S.Chand
2. www.sciencedirect.com
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