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Project Network(Activity on node network (AON))

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Project network is a graphical representation of project activities using arrows and nodes, the project should have unified start and end date, drawing this network required identifying for each activity the predecessors, duration for the completion of this activity and resources. The project network can be drawn using activity on arrow network and activity on node.



Activity on node network (AON)

 In this method, the node used to represent project activities, and the arrows between activity will be used to describe the relations between project activities. From figure 1, network one. We can notice that activity B depends on activity A only. in network 2, activity D depends on C and C depends on A and B. AON methods allow for representing lag and lead of activities on the relationship arrows that connecting different activities.
Figure 1





AOA and AON

  • There is no need for dummy activity in AON. For ANA dummy activities required in some cases as mentioned before.
  • AON allowing for representing the lag and lead on the relationship arrow while AOA doesn't allow the same.
  • AOA allows for representing FS activity type only. AON recognizes all kind of activities (FS, FF, SS, SF)
  • In the AOA method. The successor activity cannot start before the precedent activity finish.

Example 1: represent the following activity using AOA and AON.







Figure 1(AOA)

Figure 2(AON)

Example 2: represent the following activity using AOA and AON.


Figure 3(AOA)

Figure 4(AON)



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