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1 reply [Last post]
Wed, 2010-04-07 12:12
Ali Farhat
User offline. Last seen 14 years 12 weeks ago. Offline
Joined: 23 Oct 2008
Posts: 120
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In contiguous logic, the FF relation will drive the succ, and the start date will be calculated backward...in other words, the start date of the activity will be determined as finish - duration with no respect to the pred.
Interr vs. Contig. only affects FF relation, by avoiding this type, there will be no diff b/w cont. and inter. logics.
Expected finish cannot be used because dates might change when updating -> expected finish usually distorts the logic.
I agree with Rafael, it is better to split the activity if necessary.

Thanx everyone
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Wed, 2010-04-07 12:42
#1
Rafael Davila
User offline. Last seen 2 days 15 hours ago. Offline
Joined: 1 Mar 2004
Posts: 5240
Groups: Spider Project Team
Ali,

Under Contiguous logic if the activity has SS and FF predecessors both logic constraints will be respected as well as the requirement for the activity to be continuous. It might be that the activity is driven by a FF link until you increase its duration enough for the SS links become driving.

Under Contiguous logic either one SS or FF link is driving while duration is contiguous. Under non contiguous logic, the release of the requirement for the activity to be contiguous allows for the first split be driven by the SS links while the last split is driven by the FF links. If you increase the activity duration there will be a point activity will become contiguous and the SS link will become the driver.

The problem is that the splitting rule, if this is what you want to model, shall not be the same for all occasions, automatic splitting shall be considered non good practice, contrary to what some are requiring or advocating, including some members of the PMI and a few surviving advocates of the Activity on Arrow network representation which initially adopted the non contiguous calculation of early dates.

Best regards,
Rafael
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