Project management, del 1

Question 1

What is PERT?

Answer 1

Programme Evaluation and Review Technique
Firstly developed by US navy for Polaris missile project

Developed to handle uncertain activity times

Question 2

What is CPM?

Answer 2

Critical Path method

Developed by Du Pont & Remington Rand

Developed for industrial projects for which activity times generally were known

Question 3

How are the two methods used today and for what?

Answer 3

Todays project management software packages have combined the best features of both approaches.
Used to plan, schedule and control:

Individual activities that make up a project

R&D of new products and processes

Construction of buildings and highways

Maintenance of large and complex equipment

Design and installation of new systems

Question 4

What is a complicating factor with many activities?

Answer 4

Projects may have thousand of activities. Some activities depend on the completion of other activities, meaning that they can’t be started before others are completed. This is a complicating factor, the delay.

Question 5

What does PERT/CPM answer?

Answer 5

– What is the total time to complete the project?
– What are the scheduled start and finish dates for each specific activity?
– Which activities are critical and must be completed exactly as scheduled to keep the project on schedule?
– How long can noncritical activities be delayed before they cause an increase in the project completion time?

Question 6

What is a project network, nodes, arcs and critical path?

Answer 6

A project network is constructed to model the precendence of the activites

The nodes of the network = activites

The arcs of the network = precedence relationships of the activites

A critical path = a path consisting of activites with zero slack

Question 7

What 2 (3) stages has CPM?

Answer 7

Step 1 = mowing forwards
Earliest start and finish times

Step 2 = moving backwards
Latest start and finish times

Step 3 = Determining the critical path
Slack

Question 8

Calculate earliest finish time

Answer 8

Earliest start time (EF för tidigare aktivitet) + Time to complete activity (formel finns)

Question 9

Vad är latest finish time för sista aktiviteten i projeketet om earliest finish är 20?

Answer 9

20. Alltid samma

Question 10

Calculate latest start time

Answer 10

Latest finish time (LS för aktiviteten innan) – Time to complete activity i

Question 11

Calculate slack

Answer 11

Slack = Latest start – Earliest start
Slack = Latest finish – earliest finish

Slack = 0 –> critical and no delay is available