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Project Network(Activity on arrow network (AOA))

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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 arrow network (AOA)

 activity on this method represented by an arrow, while the nodes represent the start and end for activity, the lenght of area has no significant effects. figure 1 showing AOA network. in network number 1, activity B cant start before activity A completed. 5 and 10 represent the start and for the activity. 

 there some important point you should follow:

  • Each activity should have a unique i and j, i will be placed inside the rear node while j at head node, i>j.
  • it is recommended to have gape between i and j to accommodate missed activities.
  • avoid drawing back arrows

Figure 1

in the event of having one or more of activities leaving the same node and arriving at the same node as shown in figure 2., in this case, we will use a dummy activity with zero duration and no resources. the arrow of activity is drawn dashed. another case when one activity has two predecessors and another activity depend on one of these preceding activities. 

Figure 2



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