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Manpower leveling and Calculation of Total Float

11 replies [Last post]
Tue, 2007-05-29 05:10
Ghaith Al-Hiyari
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Can P3 Calculate the total float while scheduling , taking into consideration the manpower leveling?

In other words can i affect the total float shown on the program by Manpower leveling?

The logic says that Non time constrained manpower levelling would affect the project completion should the manpower is not sufficient; how can i reflect that on the total float? it is easier to other people to understand it if the float changes...is it possible?...any advise?
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Tue, 2007-05-29 10:54
#1
Ghaith Al-Hiyari
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I thank you once again for the time and information

Ghaith
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Tue, 2007-05-29 10:47
#2
Vladimir Liberzon
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I understand and share your position. I suggested to do it as one time solution just for demonstration of real total floats. Of course these links shall be immediately deleted after getting necessary report.

You can download Spider Project Demo from http://www.spiderproject.ru/spider_ep.php
It has 40 activities limitation.
The package is widely used in Russia and Eastern Europe and at the moment has customers in 19 countries. It can export/import projects into text, mpx, MS Project, P5 and any SQL database (SQL Server, Oracle), so communications will not create problems. But export/import module is not included in Demo.

In Publication section http://www.spiderproject.ru/publ_e.php#eng you can read papers describing some approaches used in this software.
If you will try this package and will have any questions don’t hesitate to ask me directly especially if you will not find some necessary feature.
Regards,
Vladimir
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Tue, 2007-05-29 10:10
#3
Ghaith Al-Hiyari
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Thank you Vladimir,

Linking activities that are not actually linked inorder to obtain correct float is like correcting something wrong with a bigger mistake, at least the way i see it.It is one of the things that i fight all the time and which is again, the most common used here in the UAE at least.

The problem with creating false links to get a sequence of work is that it is false and theoretically incorrect. as it serves only one sequence while the sequence is not actually important rather than te manpower availability, the schedule will start giving disasterous results if you change the sequence for any reason later, which might put you in even further trouble.......i didnt imagine that P3 would have a mishap as this one....i havent tried spider ever...is it that common nowdays??
where can i get more information on it?
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Tue, 2007-05-29 09:59
#4
Vladimir Liberzon
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With P3 the only solution I see is to create links between activities that were leveled in accordance with their order in the leveled schedule. In this case Primavera will show correct total floats after scheduling.
Another solution is to import your schedule in Spider Project and to level it there. It can be done if you will export your project into mpx format and send it to me. In Spider schedule you will see resource critical path and maybe the project duration will become shorter due to Spider optimization algorithms. I can send you back Spider Project schedule in pdf format and in P3 mpx (it is not standard).
Regards,
Vladimir
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Tue, 2007-05-29 07:53
#5
Vladimir Liberzon
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Ashraf,
just make very simple resource constrained schedule and look at the results. These packages do not take into consideration resource constraints creating backward schedules. So calculated floats are not feasible. With P3e (P5) it is even more strange. Recently I created simple schedule where P5 showed positive float for the last activity. This I cannot explain at all.
At the moment I don’t have P3 in my notebook. I just remember this problem from the times when I used it. Inform me if you will not notice the problem and I will prepare an example later.
Regards,
Vladimir
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Tue, 2007-05-29 07:37
#6
Ashraf Jahangeer
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Vladimir,

Can you explain bit more in detail how P3 calculates wrong resource constrained floats.

Regards,

Ashraf

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Tue, 2007-05-29 06:53
#7
Vladimir Liberzon
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Be careful. P3, MS Project and P3e calculate wrong resource constrained floats.
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Tue, 2007-05-29 06:45
#8
Ashraf Jahangeer
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Make the resource which you are levelling as driving and it will reflect on the float.

Regards,

Ashraf
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Tue, 2007-05-29 09:28
#9
Ghaith Al-Hiyari
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Thank you vladimir,

My case is i want to drive the project forward as i have more than 20 activities in parallel and i want to show that it cannot happen in reality because sufficient number of manpower are not available, so i made forward levelling with no constraint on time the result on the total project network is logical and is correct, but it is not shown in the total float column.

People who are not aware of this technique would not understand that these activities are critical, and that they are on the critical path since they show psoitive float!, the total float column is not showing consumption of the float due to driving the activity because of insufficient amount of manpower. i tried putting tem all driving as the guy from kuwait said but it didnt work.

Do you have other suggestions ....solutions?

Thank you once again
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Tue, 2007-05-29 09:14
#10
Vladimir Liberzon
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Groups: Accreditation Editors, Board of Advisors, Civil Engineering, GPCCAR Editors, Petro-Chem / Oil & Gas, Regional Representatives, Spider Project Team, TURNAROUND & SHUTDOWN (T/A & S/D)
Ghaith,
I know that this problem existed in P3 when I used it several years ago. I am sure that it was not solved. I suggest to create small project with two resources that are limited and with resource conflicts. Look if the floats that P3 shows are feasible. If you can really postpone activity execution using this floats without postponing project completion.
If you will not see the problem I will create an example to explain what I mean.
Regards,
Vladimir
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Tue, 2007-05-29 09:07
#11
Ghaith Al-Hiyari
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Thank you Guys for replying....so thats it?...i just make it a driving resource and the problem is solved?

By the way i work on P3....so is vladimir’s comment applicable on P3 or only on P5?
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