es-322 module 3_part_1[lec. 1&2]2
DESCRIPTION
engineering managementTRANSCRIPT
SURAH – 1 Al- Fatiha
1. Sa Ngalan ni Allah, ang Pinakamahabagin, ang
Pinakamaawain. 2. Ang lahat ng kaluhalatian at pagpup[uri ay kay Allah, ang Rabb
(Panginoon, Tagapanustos at Tagapagtangkilik). Ng lahat ng linalang.
3. Ang Pinakamahabagin, ang Pinakamaawain
4. Ang tanging may Hawak. (o pagpapasya) sa Araw ng paghatol.
5. Ikaw (po) lamang ang aming sinasamba at ikaw (po)
lamang ang aming hinihingan ng tulong.
6. Iyomg patnubayan kami sa matuwid na landas.
7. Sa landas ng mga ginawaran Ninyo ng inyong mga
biyaya at hindi sa landas na umaani ng Iyong pagkapoot,
gayun din naman ay hindi sa landas ng mga napaligaw sa
patnubay.
( Ang Panimula ) 7- Ayath
1) Si Propeta Muhammad (sawa) ay
nagsabi. “Sinumang nalulugod na
ang Allah ang Siyang Panginoon.
Islam ang pananampalataya, at si
Muhammad ay Sugo, malalasap niya
ang tamis ng pananalampataya”.
(Muslim)
What is PERT & What is CPM
PERT – is a Program Evaluation and Review
Technique
CPM – Critical Path Method
PERT & CPM were developed
independently in the later part of 1950’s.
This two are networks. A technique,
used for planning and coordinating large
scale project.
CPM was designed as a tool for planning, scheduling,
and control of construction work. Its emphasis was on
the work or activities to be manage. The network
diagram defined and focused attention on the job to be
accomplished. The schedule derives the earliest and the
latest times for their start and finish.
PERT was developed as a result of looking for an
improved method of planning and evaluating progress
of a large scale research and development program. It
was designed to provide the management a periodic
reporting of current status and an outlook for the future
on meeting approved plans and schedules. It answer the
questions such as “Is this a feasible schedule? And what
are the probabilities of making it?
Three Phases of PERT/CPM
1. Planning
2. Scheduling
3. Control-Monitor
1. Planning – is defined as determining the
relationship between the work operation and the
sequence in which they are to be performed.
2. Scheduling– is defined as the process of
translating the arrow diagram into the time table
calendar days.
3 Control– monitor – Flexibility and updated
re-computations brought about by changing
conditions is the key to a successful network
programming.
Network
Diagram
The Network
Fundamentals
A ) Network Convention:
Two Convention of Network
Diagram
1 – Activity on Arrow (AOA)
- Using arrow to designate activities
2 – Activity on Node (AON)
- Using node to designate activity
Illustration :
1 2
j- node i- node
A B
AOA
AON
Events Events ACTIVITY
B) Elements of Network Diagram
1-Work B cannot start until after work A is
Completed
A B
C
2- C cannot start until both A & B are
Completed
3 - A must be completed before either B or C can
start.
A
4 – Both A & C must be completed before either B
or D can start.
B
A
D
C
5 – Both A & B must be completed before D can
start C depends only on A. x is called “dummy”
x
Dummy – is an arrow on a network showing the dependent relationship
between two activities. However dummy activity does not represent actual
work efforts. And do not consume time. Dummy activity may be used in the
network to distinguish between two or more parallel activities.
B
A
D
C
6 – C depends on A &B. D depends on A only y is
called “dummy”
y
C) Principles in Networking or Arrow Diagram
Excavation
Principle # 1: That everything in the network or arrow
diagram must have a meaning.
a) Every arrow represent an item of work and is called
Activity.
b) An Event is the starting point of an Activity represented
by a circle, square or any geometrical form..
event
c) An Activity is dependent upon and cannot begin
until after the completion of all preceding Activities.
Order and deliver cement
Making forms Pour footing slab 3
Order and deliver
Making forms Four footing slab
d) All activities that start with the same event cannot
begin until after the completion of all activities that
enter that event.
pedestal
3
1 3 4
Principle # :2
That an activity has a single definite starting point and a
single definite ending point.
An arrow in the network must satisfy two basic questions:
1) What activities must be completed before this one can
start?
2)What activities cannot be started if this one is not
completed?
2 Digging Forms
Block laying
Wall footing
Principle # :3
The network (arrow diagram) does not describe time
relationships but rather dependency relationship.
1 A 2
4
3 D
E
Principle # :4
That the network (arrow diagram ) is hardly ever done by
a single person.
The accomplishment of the schedule made in the
network diagram is influenced by several number of
people who have something to do with the project
and should be consulted when making the network.
Likewise, the sub-contractors and suppliers
should be asked to review the network to be sure
that the activities affecting their participation is
accurately and realistically describe
Fundamental Elements
of PERT/CPM
Networking
The fundamental elements of PERT/CPM networking
activities are:
Time Activity and Events
Activity – is the work operation required to complete a
task or in some cases, a segment of that task. In short, it
is the actual work between events.
Events – is a point in time signifying the beginning or
end of one or more activities. It denotes the completion
of all preceding or predecessor activities and the
beginning of one or more succeeding activities
Time- is the duration it takes an activity to be finished.
In short, this is the normal duration of a task.
Illustration:
Activity Precedes Expected time (days)
A C, B 4
C D 12
D I 2
B I 5
E F 3
F J 8
I J 12
J END 9
G H 1
H K 3
K END 15
From the following table of information, a) Draw a
network diagram, b) Find the Critical Path, c) Determine
the expected duration of the project.
Solution:
Acti
vity
Precedes
Expected
time (days)
A C, B 4
C D 12
D I 2
B I 5
E F 3
F J 8
I J 12
J END 9
G H 1
H K 3
K END 15
1 6
7
5 4
3
2
E =3
D = 2
B = 5 I = 12
J = 9 F =8
H = 3 K =15
start
end
a) Draw a Network Diagram
4
2
3
8
9
10
11
12
Solution:
1
9 6
8
7
5
4
3
2
E =3
B = 5
F =8
H = 3 K =15
start
end
b)
Path 1: A,C,D,I,J = 4+12+2+12+9
= 39 Path 2: A,B,,I,J = 4+5+12+9 =
30
Path 3: E,F,J = 3+8+9 =
20
Path 4: G,H,K1+3+15
=19
DURATION = 39
Days
1-2-5-7-8-9= C.P.
c)
b) Find the Critical Path,