es-322 module 3_part_1[lec. 1&2]2

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,