Guild of Project Controls: Compendium | Roles | Assessment | Certifications | Membership

Tips on using this forum..

(1) Explain your problem, don't simply post "This isn't working". What were you doing when you faced the problem? What have you tried to resolve - did you look for a solution using "Search" ? Has it happened just once or several times?

(2) It's also good to get feedback when a solution is found, return to the original post to explain how it was resolved so that more people can also use the results.

Activity-On-Arc(AOA), Activity-On-Node(AON).

17 replies [Last post]
Fri, 2005-04-29 04:39
Mustafa Ege
User offline. Last seen 15 years 11 weeks ago. Offline
Joined: 29 Apr 2005
Posts: 3
Groups: None
In network planning techniques, such as PERT,CPM,
There are two possible ways of representing
each project: Activity-On-Arc(AOA), Activity-On-Node(AON).

we know that some project management computer packages use both the network representations.

is there real need for using the AoA representation (Because of minimum dummy arc problem)?

If the AoN representation is only used in project scheduling, what is the nature of the mistake made here?

I couldn’t find any clear-cut and admissible explanation.
Thanks to everybody for their contributions.
Mustafa Ege
Top

Replies

Mon, 2011-07-25 08:37
#1
Mike Testro
User offline. Last seen 5 weeks 1 day ago. Offline
Joined: 14 Dec 2005
Posts: 4418
Groups: Building Information Modelling, Content Moderators, GPCCAR Editors

Hi Jillian

Welcome to Planning Planet - as you have found this is the forum to learn and share knowledge and experience.

Please remember however that It is not a good idea to liven up a long dead discussion.

BTW whats with the Rabbit Hutch Shop?
 

Best regards

Mike Testro

Top
Sun, 2011-07-24 19:19
#2
jillian grey
User offline. Last seen 12 years 39 weeks ago. Offline
Joined: 24 Jul 2011
Posts: 2
Groups: None

Thank you for sharing these helpful information. I learned a lot from it. I really appreciate you guys sharing these information with us.

 <SPAM LINK DELETED BY GARY W>

Top
Fri, 2008-03-14 08:40
#3
John Cornish
User offline. Last seen 10 years 18 weeks ago. Offline
Joined: 22 Nov 2007
Posts: 49
Groups: Accreditation Editors
Hi Mal,

Thanks for your supportive comments. And absolutely right to learn for yourself all about forward/backward passes. The S/W just does it faster.

I would be interested to learn what planning tools you’re using in the pharmaceutical industry.

At www.microplanning.co.uk there are two useful .docs to download to help compare/contrast project planning tools. You’re very welcome to make use of them.

Cheers
John
Top
Fri, 2008-03-14 05:46
#4
Mal Leadbetter
User offline. Last seen 10 years 32 weeks ago. Offline
Joined: 22 Aug 2001
Posts: 61
Groups: TILOS
In responce the Brads point about Pertmaster, when I started planning we used Hornet. The Arrow on Arrow drawing was based upon A1 sheets, activity numbers taken from a rows and column numbering. So simple! Especially as my senior planner made me draw every thing out be hand first! And then do a forward / backward pass before putting it into the computer. His idea of making me learn some planning principles and not just software. Stood me in good stead since!

Mal
Top
Wed, 2008-03-12 18:55
#5
John Cornish
User offline. Last seen 10 years 18 weeks ago. Offline
Joined: 22 Nov 2007
Posts: 49
Groups: Accreditation Editors
Hi Brad,

Take a look at Micro Planner X-Pert. This package was designed by Project Managers for Project Managers and yes includes all the goodies like PERT Diagrams with ADM or if you must PDM.

try the free download to compare/contrast with other planning tools.

cheers
John
Top
Fri, 2007-11-09 03:55
#6
Brad Lord
User offline. Last seen 9 years 46 weeks ago. Offline
Joined: 27 May 2003
Posts: 256
Groups: None
the old days of arrow on node planning, Did any body else use an old MSDOS programme called Pertmaster Advanced which allowed you to do both planning techniques, what a joy it was

regards

Top
Fri, 2007-11-09 03:47
#7
A D
User offline. Last seen 3 years 23 weeks ago. Offline
Joined: 20 May 2007
Posts: 1027
Groups: Accreditation Editors
AOA - Abort Once Around (such a old topic)

Yes, its true that professionals use both the terminology, Arc as well as arrow.

Depends from which school you have passed from?

Cheers,

Rav
Top
Wed, 2007-11-07 07:03
#8
Siva guru
User offline. Last seen 13 years 28 weeks ago. Offline
Joined: 10 Nov 2006
Posts: 8
Groups: Petro-Chem / Oil & Gas
AOA can represent both Activity on ARROW &Activity on ARC,
as in scheduling we find authors using both the terminologies interchangably.
Top
Tue, 2007-11-06 23:23
#9
Dayanidhi Dhandapany
User offline. Last seen 3 years 3 weeks ago. Offline
Joined: 18 Mar 2003
Posts: 470
Groups: None
As Ron rightly mentioned, AOA should stand for Activity on Arrow, from where the term Arc comes to replacing the Arrow?
Top
Tue, 2005-05-31 17:08
#10
Bernard Ertl
User offline. Last seen 9 years 19 weeks ago. Offline
Joined: 20 Nov 2002
Posts: 757
Groups: Petro-Chem / Oil & Gas, TURNAROUND & SHUTDOWN (T/A & S/D)
IMO, most software supports PDM/AON because the market demand was there. It is easier (more intuitive) for people to work with. Training people to schedule on ADM/AOA systems who don’t know anything about it requires a *lot* of patience.

Bernard Ertl
eTaskMaker Project Planning Software
Top
Tue, 2005-05-17 02:15
#11
Raj Maurya
User offline. Last seen 2 years 42 weeks ago. Offline
Joined: 17 Jul 2004
Posts: 132
Groups: Petro-Chem / Oil & Gas
AON (PDM) is developed to fulfill the shortcomings of AOA method in case of complex project. I guess that’s why most of the softwares support it.
Top
Mon, 2005-05-16 09:18
#12
Stephen Devaux
User offline. Last seen 17 weeks 6 days ago. Offline
Joined: 23 Mar 2005
Posts: 667
Groups: Content Moderators
"But in general activities are not very straight forward with FS relation, I guess that is the reason most of the programme supporting AON(PDM) technique there you can define all other type of dependencies."

Any relationship that can be modelled with complex dependencies and lags can also be modelled using only FS relationships, with greater decomposition and milestones. The FS-only network will have more activities and milestones, but it will be easier to focus on task-completion criteria. And computing critical path DRAG is usually easier in FS-only networks.
Top
Thu, 2005-05-12 10:55
#13
PRABHATH PREMASURIYA
User offline. Last seen 9 years 10 weeks ago. Offline
Joined: 1 May 2005
Posts: 9
Groups: GPC Qatar
AOA - Activity On Arrow
Finish to Start (FS) relationship only; Dummy activities allowed

AON - Activity On Node
Also called Precedence Diagram Method.
Represent improvement to PERT and CPM by adding lag relationships to activities.
All the four types of relationships allowed.
Start to Start (SS), Start to Finish(SF), Finish to Start (FS) and Finish to Finish (FF).
Arrow indicate dependancy, No dummy activities.
Top
Tue, 2005-05-03 13:24
#14
Rashid Iqbal
User offline. Last seen 17 years 3 weeks ago. Offline
Joined: 3 May 2005
Posts: 94
Groups: None
Most of the programs inculding Primavera and MS Project use AON. AOA lacks different type of relationships which enable the AON user to model a real life dynamic situation to a ’considerable’ extent.

Though one thing I would like to submit that whenever someone is trying to explain a process, he goes by AOA. AON can’t beat the simplicity of AOA.

Reagrds
Rashid Iqbal
Top
Sat, 2005-04-30 00:49
#15
Raj Maurya
User offline. Last seen 2 years 42 weeks ago. Offline
Joined: 17 Jul 2004
Posts: 132
Groups: Petro-Chem / Oil & Gas
AOA (ADM) is used when the relationship among the activities are clearly defind as FS. But in general activities are not very straight forward with FS relation, I guess that is the reason most of the programme supporting AON(PDM) technique there you can define all other type of dependencies.
Top
Fri, 2005-04-29 11:28
#16
Ronald Winter
User offline. Last seen 3 years 6 weeks ago. Offline
Joined: 4 Jan 2003
Posts: 928
Groups: None
I always though that ’AOA’ stood for Activity-on-Arrow, as in arrow diagraming. Did I sleep through another class and miss something?
Top
Fri, 2005-04-29 10:08
#17
Bernard Ertl
User offline. Last seen 9 years 19 weeks ago. Offline
Joined: 20 Nov 2002
Posts: 757
Groups: Petro-Chem / Oil & Gas, TURNAROUND & SHUTDOWN (T/A & S/D)
IMHO, AON (or PDM) is easier for schedulers to conceptualize in the head from a list of predecessors/successors. Ie. there are less numbers/codes/labels representing the logic network.

AOA (or ADM) is more explicit when the logic network is graphed, but is more difficult to conceptualize from a list of I,J nodes.

Bernard Ertl
eTaskMaker Project Planning Software
Top