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Critical Path Method

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CRITICAL PATH METHOD
(CEE 320 – VDC SEMINAR) 4 February 2009

Jesse Santiago & Desirae Magallon

Overview
Background & History CPM Defined The CPM approach Definitions Class Exercise

Background & History
Developed in the 1950s by the US Navy Originally, the critical path method considered only logical dependencies between terminal elements Since then, it has been expanded to allow for the inclusion of resources related to each activity, through processes called activity-based resource assignments and resource leveling. Critical Path Method for the construction industry
Non-computer approach John Fondahl

John Fondahl
Stanford CE Professor Emeritus – 35 years Passed away last September 13th, 2008 US Marine Corps Sergeant in Iwo Jima
His father was USMC LtCol

Co-founder of the CEM program 1961 Paper for the US Navy – "Non-Computer Approach to the Critical Path Method for the Construction Industry"

What is CPM?
The Critical Path Method or Critical Path Analysis, is a mathematically based algorithm for scheduling a set of project activities It is an important tool for effective project management Commonly used with all forms of projects, including construction, software development, research projects, product development, engineering, and plant maintenance, among others Any project with interdependent activities can apply this method of scheduling

What is CPM?
The essential technique for using CPM is to construct a model of the project that includes the following:
A list of all activities required to complete the project (also known as Work Breakdown Structure) The time (duration) that each activity will take to completion The dependencies between the activities.

What is CPM?
CPM calculates
The longest path of planned activities to the end of the project The earliest and latest that each activity can start and finish without making

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