Chapter 6

Question 1

Developing a Project Network

Answer 1

What is a project network?
What is a critical path?
What is sequencing?

Question 2

The Project Network

Answer 2

A flow chart that graphically depicts the sequence, interdependencies, start and finish times of the activities within the project job plan that is the critical path through the network.

Provides the basis for scheduling labor and equipment.
Enhances communication among project participants.
Provides an estimate of the project’s duration.
Provides a basis for budgeting cash flow.
Identifies activities that are critical.
Highlights activities that are “critical” and can not be delayed.
Helps project managers get and stay on plan.

Question 3

Constructing a Project Network

Answer 3

Activity
Merge Activity
Parallel (Concurrent) Activities

Question 4

Activity

Answer 4

an element of the project that requires time.

Question 5

Merge Activity

Answer 5

an activity that has two or more preceding activities on which it depends.

Question 6

Parallel (Concurrent) Activities

Answer 6

Activities that can occur independently and, if desired, at the same time.

Question 7

Path

Answer 7

a sequence of connected, dependent activities.

Question 8

Critical path

Answer 8

the longest path through the activity network that allows for the completion of all project-related activities. Delays on the critical path will delay completion of the entire project.

Question 9

Event

Answer 9

represents a point in time where an activity starts or ends.

Question 10

Burst activity

Answer 10

has more than one activity immediately following it.

Question 11

Activity-on-node (AON)

Answer 11

uses a node to depict an activity.

Question 12

Activity-on-arrow (AOA)

Answer 12

uses an arrow to depict an activity.

Question 13

Basic Rules in Developing Project Networks

Answer 13

Networks typically flow from left to right.
An activity cannot begin until all preceding connected activities are complete.
Arrows indicate precedence and flow and can cross over each other.
Each activity must have a unique identifying number that is greater than any of its predecessor activities.
Looping is not allowed.
Conditional statements are not allowed.
Use common start and stop nodes.

Question 14

Network Computation Process

Answer 14

Forward Pass—Earliest Times
How soon can the activity start? (early start—ES)
How soon can the activity finish? (early finish—EF)
How soon can the project finish? (expected time—ET

Question 15

Forward Pass Computation

Answer 15

Add activity times along each path in the network (ES + Duration = EF).
Carry the early finish (EF) to the next activity where it becomes its early start (ES) unless…
The next succeeding activity is a merge activity, in which case the largest EF of all preceding activities is selected.

Question 16

Network Computation Process

Answer 16

Backward Pass—Latest Times
How late can the activity start? (late start—LS)
How late can the activity finish? (late finish—LF)
Which activities represent the critical path? (CP)
How long can activity be delayed? (slack or float—SL)
How long an activity can be delayed without effecting the successor activity = FS (free slack)

Question 17

Backward Pass Computation

Answer 17

Subtract activity times along each path in the network (LF - Duration = LS).
Carry the late start (LS) to the next activity where it becomes its late finish (LF) unless …
The next succeeding activity is a burst activity, in which case the smallest LF of all preceding activities is selected.

Question 18

Use of Lags

Answer 18

Lags
The minimum amount of time a dependent activity must be delayed to begin or end.
Lengthy activities are broken down to reduce the delay in the start of successor activities.
Lags can be used to constrain finish-to-start, start-to-start, finish-to-finish, start-to-finish, or combination relationships.

Question 19

Use of Lags - Relationships

Answer 19

Finish-to-start relationship – one activity must be complete before the next activity can be started

Start-to-start relationship, activities can start before the predecessor is completed

Question 20

Hammock Activity

Answer 20

Spans over a segment of a project.
Has a duration that is determined after the network plan is drawn.
Is used to aggregate sections of the project to facilitate getting the right amount of detail for specific sections of a project.
Is very useful in assigning and controlling indirect project costs.

Question 21

WBS & Project Networking

Answer 21

How is project networking different from WBS?
How are the WBS & Project Networking linked?
Why have a WBS? Why not have just a Project Network?