Material driven duration help

[Tony]

I am trying to drive a task by the volume of material to be used. What
I want to be able to do is see how long the task will take given a
total volume to do.

The problem.
I million accounts to update and they can only be updated on specific
nights of the month, on each of those night I can only update 1500
accounts.

My customer want to know what happens to the schedule if we can do 2000
per night.

I set up a calender for the available nights of the month and created a
resource the "accouts system" and assigned the calendar to it. I can't
work out how to tell it that it needs to do 1500 or 2000 acounts per
night out of the million accounts and automatically change the duration
of the task.

Can anybody please help me as I have been going round in circles on
this for ages.

Tony.

 

[SpiroT]

You may have to try doing it differently.

Make account system a work instead of material resource.
Change task type to Fixed Work.
Change the % of assigned resource (account system) accordingly, Eg., 1500
accounts = 100% and 2000 = 2000/1500 = 133%. You can even use overtime.

Work = the time it would typically take to process 1,000,000 accounts.

 

[TonyN]

Hi Spiro,

Thanks for the reply, I don't think I explained myself correctly. The
"account system" was a work resource with a calendar so I could get the
working/non-working days assigned, I then tried to add material resouce
to drive the volume of work.

And that is where it fell down. I am using Project 2K3

Regards,
TonyN

 

[Steve House [Project MVP]]

You have a mistaken notion of what material resources are, I'm afraid. A
material resource is something that is either consumed by doing the task -
fuel for a bulldozer, for example - or something that is incorporated into
the task's deliverable - bricks for a wall you are building. Project
considers materials to be infinite in supply and always available - you
always have as many bricks as you need on hand. While their availablility
doesn't enter the picture from a scheduling standpoint, their consumption
contributes to the overall project cost.

I'll bet you are thinking of the computer system processing the data as a
material resource but it is not - it is a work resource and the duration of
tasks it is assigned to depends on the rate it does the work. That's
identical to a human worker where the duration of a task he is assigned
depends as well on the rate he works. A work resource's assignment
percentage represents its effort which effectively is the rate at which it
generates output - ie, a painter working 100% can paint 10 ft^2 per hour so
it takes 10 hours to paint 100 ft^2. You could arbitrarily say that 1000
accounts per night represents 100%. Your initial duration estimate would be
1000 nights (Tales of the Arabian Nights? LOL). Assign the accounting
system 100%. Then to see what it would be if you increased to 2000 accounts
per night, increase the assignment to 200% and the duration will contract.

Frankly I don't know why you'd bother trying to model it this way in Project
though. Calculating how many hours it will take to process X accounts at Y
per hour is just a matter of simple arithmetic X/Y - figure it by hand and
simply enter the result into the duration field. That's the idea of the
whole estimating process in the first place and part of the information you
give to Project so it can calculate the overall work schedule.

 

[TonyN]

Hi Steve,

Thanks for your explanation, I was confused. The reason I wanted to
use project is there are a number of dependencies on the progress and I
wanted to see where they all fell out and I was told project could do
what I wanted.
Ah well back to good old fashiond pen & paper.
again thanks for the help.

TonyN

 

[Steve House [Project MVP]]

If I understood your first post it will do what you want, I'm pretty sure.
You said you wanted to model the effect of increasing or decreasing the
amount of accounts processed per evening on the total time it will take to
do the project. Use the "Accounting System" as a work resource.
Aribtrarily define 100% resource assignment as meaning your present 1000
accounts per evening and assign "Accounting System" to the "Process
Accounts" task at a 100% assignment level. Now to experiment, to see what
timeframe would result if you could process 2000 accounts per evening, set
the resource assignment to 200%. Project will recalculate the duration of
that task for you. You were on the right track, its just that the
accounting system is not a material resource.