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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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My name is Mohammad Hamdan, and I am a Civil/bridge Engineer with extensive professional background and experience in the field of construction. I have 10+ years of experience in the construction field. During my professional career, my emphasis has been placed on structural projects, mainly bridges, infrastructure and roads. Reading and practicing the design of structures is my passion.i was lucky to be a part of a big team that executed major highway interchanges. I believe in spreading the knowledge, thus, i compose these courses to share my experience and knowledge. My course focuses on the practical side of construction field. On other word, i am sharing some of what new engineers need to know about construction field. Beside working on construction field, i love writing some articles on my website ( curious civil engineer) Moreover, i wrote some engineering papers, you can check them  by searching my name on Google (Mohammad mamon Hamdan)