PROJECT NETWORK DIAGRAM

1
PROJECT NETWORK DIAGRAM

• PREPARED BY
• NOR AZAH BINTI AZIZ
• KOLEJ MATRIKULASI TEKNIKAL KEDAH

2
OBJECTIVES

• Define Network Diagram
• Purpose of Network Diagram
• Method Activity On the Node (AON)
• Identify ES, EF, LS, LF using Forward Pass
  Calculation and Backward Pass calculation
• Identify Critical Path
• Identify Slack Time

3
INTRODUCTION

• A PND is a pictorial representation of the
  sequence in which the project work can be done.
• The activities and its duration are the basic
  building blocks needed to construct a graphic
  picture of the project
• Its provide
• - the earliest time at which work can be begin
  on every activity that makes up the project
• - the earliest expected completion date of the
  project

4
IMPORTANCE OF ND

• ND can be used for
• i) Planning gives a clear graphical picture of
  
• the relationship between project activities
• ii) Implementation when updating the project
  file with activity status and estimate to
  completion data, the ND is then automatically
  updated and can be printed or viewed
• iii) control while updated ND will retain the
  status of all activities, the best graphical
  report and controlling project work will be
  Gantt Chart

5
METHODS

• THE ACTIVITY ON THE NODE ( AON)
• Basic unit of analysis in ND is the activity
• Each activity is represented by a rectangle (
  activity node)
• Arrows represent the predecessor/successor
  relationship between activities
• Every activity in the project will have its own
  activity node ( each rectangle)

6
METHODS

• THE ACTIVITY ON THE NODE ( AON)

7
METHODS

• THE ACTIVITY ON THE NODE ( AON)
• Dependencies
• A dependency is simply a relationship that exists
  between pairs of activities
• 4 types of activity dependencies

FS A finishes, B start
8
METHODS

• THE ACTIVITY ON THE NODE ( AON)
• Dependencies

FF A finishes, B finish
SS A start, B start
9
METHODS

• THE ACTIVITY ON THE NODE ( AON)
• Dependencies

SF A starts, B finish
10

• THE ACTIVITY ON THE NODE ( AON)

11

• THE ACTIVITY ON THE NODE ( AON)

Creating an initial project network schedule
Forward Pass calculations
12
EST, LST, EFT, LFT

• CPM uses the following times for an activity
• EST - Early Start time is the earliest time the
  activity
• can begin
• LST - Late Start Time is the latest time the
  activity can begin
• - still allow the project to be completed on
  time
• EFT - Early Finish Time is the latest time the
  activity can end
• LFT - Late Finish Time is the latest time the
  activity can end
• - still allow the project to be completed on
  time

13
Forward Pass calculations
14
Backward Pass calculations
15
CRITICAL PATH METHOD (CPM)

• An effective way to analyze complex projects
• Represent the critical set of activities to
  complete a project
• Help to focus on essential activities which are
  critical to run the project
• Allows the project manager to concentrate on
  important activities
• CP is the longest path on ND and the most
  important part
• Any delays on the CP will lead to delay of the
  project

16
CRITICAL PATH METHOD (CPM)
17
FLOAT

• Also known as slack, total float and path float
• Is computed for each task by subtracting EFT from
  the LFT
• ( _at_ the early start from the late start)
• Is the amount of time the task can slip without
• delaying the project finish date.
• Free float is the amount of time a task can slip
• without delaying the early start of any task
• that immediately follows it.

18
Slack Time calculations
19
EXAMPLE
1. TABLE 1 shows the activities and the
durations required to complete a construction
project, including the precursor activity.
Refering to the TABLE 1 i) draw the
project network diagram. ii)
state the activities on the critical path. iii)
calculate the minimum duration of the
project.
Activity Precursor Duration (week)
A - 7
B A 6
C A 5
D A,B 4
E B,C 3
F D,E 2
20
project network diagram