Scheduling%20Computations%20for%20Precedence%20Networks

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Scheduling ComputationsforPrecedence Networks
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Tabular Format (Precedence Diagram)

• Can be carried out on the tabular form without
  reference to the diagram.
• Advantage the time required to construct the
  diagram is eliminated.

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Link Lag

• A link lag is the difference between the early
  start date of an activity and the early finish
  date of the preceding activity
• LAGij ESDj - EFDi

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Determining log

• Examples
• LAG 5-10 ESD 10 - EFD 5 4 - f 4 0
• LAG 15-25 ESD 25 - EFD 15 12 - 7 5
• LAG 20-25 ESD 25 - EFD 20 12 - 6 6

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Determining the Free-Float

• Free Float is the minimum of the log of the link
  that follow an activity.
• Look at the Pre. column to find the same number
  value of EF for terminal activity not following
  act.
• FFi Min?j - LAG ij
• FF 35 LFD 35 - EFD 35 20 - 20 0

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Determining the Total Float Backward

• TF i Min (log ij TF j )
• Take TF of the terminal activity 0
• or TF 35 LFD 35 - EFD 35 20 - 20 0

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Determining the Total Float Backward (cont.)

• TF 30 Min (log 30-35 TF 35 )
• Min ( 7 0 ) 7
• No other link
• TF 20 Min LAG20-25 TF 25 Min 60
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• LAG20-30 TF 30
  17

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INTF Float

• INTF TF - FF

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• If the free float is zero - no INDF
• INDF j FF j - Max _ I ( TF I - LAGIJ )
• INDF 20 FF 20 - Max ( TF 5 - LAG5-20 )
• 1- (0 -0 )1
• INDF 30 FF 30 - Max TF 15 - LAG15-30
• TF 20 - LAG20-30
• 7 - 5 - 0 2
• 6 - 1

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Float Determination -Sample Precedence Network
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Late Date Determination -Sample Precedence
Network
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Lag Determination -Sample Precedence Network