Prepared by Scott M. Shafer, Updated by William E. Matthews and Thomas G. Roberts, William Patterson University Copyright 2007 John Wiley & Sons, Inc. 5-1 Mantel, Meredith, Shafer, and Sutton Copyright John Wiley & Sons, Inc. All rights reserved. Reproduction or translation of this work beyond that permitted in Section 117 of the 1976 United States Copyright Act without express permission of the copyright owner is unlawful. Request for further information should be addressed to the Permissions Department, John Wiley & Sons, Inc. The purchaser may make back-up copies for his/her own use only and not for distribution or resale. The Publisher assumes no responsibility for errors, omissions, or damages, caused by the use of these programs or from the use of the information herein. 5 – Scheduling the Project
Transcript
Prepared byScott M. Shafer,
Updated by William E. Matthews and
Thomas G. Roberts, William Patterson University
Copyright 2007 John Wiley & Sons, Inc. 5-1
Mantel, Meredith, Shafer, and Sutton
Copyright John Wiley & Sons, Inc.
All rights reserved. Reproduction or translation of this work beyond that permitted in Section 117 of the 1976 United States Copyright Act without express permission of the copyright owner is unlawful. Request for further information should be addressed to the Permissions Department, John Wiley & Sons, Inc. The purchaser may make back-up copies for his/her own use only and not for distribution or resale. The Publisher assumes no responsibility for errors, omissions, or damages, caused by the use of these programs or from the use of the information herein.
5 – Scheduling the Project
Late 1950s
• Program Evaluation and Review Technique (PERT)• U.S. Navy, Booz-Allen Hamilton, and Lockeheed Aircraft
• Probabilistic activity durations
• Critical Path Method (CPM)• Dupont De Nemours Inc. developed the method
• Deterministic activity durations
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Activity• task or set of tasks• uses resources
Event• state resulting from completion of one or more activities• consumes no resources or time• predecessor activities must be completed
Milestones• events that mark significant progress
Network• diagram of nodes and arrows• used to illustrate technological relationships
Path• series of connected activities between two events
• Critical Path• set of activities on a path that if delayed will delay completion of
project Critical Time
• time required to complete all activities on the critical pathCopyright 2007 John Wiley & Sons,
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Activities on Arrows (AOA) Network Activities on Nodes (AON) Network
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Latest Start Time (LST) – Earliest Start Time (EST) = Slack Latest Finish time (LFT) – Earliest Finish time (EFT) = Slack
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Task will be a or lower 5 percent of the time Task will be b or greater 5 percent of the time
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Task will be a or lower 10 percent of the time Task will be b or greater 10 percent of the time
6.2
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=NORMDIST(D,,,TRUE)
Note: NORMDIST is a function within Excel when using the spreadsheet method
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2 ZD
NORMINV(probability,,,TRUE)Note: NORMMINV is a function within Excel when using the spreadsheet method
Similarity• Both must enumerate the alternative path
Difference• Traditional statistics assume path
interdependence while simulation does not
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Finish of Activity A to start of Activity B linkage (F to S) Start of Activity B to start of Activity C linkage (S to S) Finish of Activity A to finish of Activity B linkage (F to F) Start of Activity A to finish of Activity A linkage (S to F)
Combines flowgraphs, probabilistic networks, and decision trees
Allows loops back to earlier events and probabilistic branching
