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(project1.mdl)

 

The most fundamental characteristic of any project is that there is something to do and it gets done, at least partially.  We start with two Levels and the flow between them:

This is a complete model.  We set initial project definition at 1000 and work flow at 100.  This is a project that should take 10 months.  Just to make sure we have time to get done we run the project for 24 months with TIME STEP at .0625  (this is 1/16th of a month and should be sufficiently fine to trap changes in project activity).  The equations are:

Work Remaining = INTEG(
-work flow,
       initial project definition)

Units: Drawing

Work Accomplished = INTEG(
work flow,
       0)

Units: Drawing

initial project definition = 1000

Units: Drawing

work flow = 100

Units: Drawing/Month 

The units of measure — Drawing — are appropriate for the design of a building.  Tasks, lines of code, or other measures could also be used.  It is important to remember that we are dealing with an aggregate representation of a project.  In reality a project is not made up of a bunch of equally sized components, but a combination of big and little things.  We are representing averages in our equations.  It is very important to keep this in mind, especially when you are working on a real problem.

When we simulate this model we see the following:

After 10 months Work Remaining is 0, but things continue to get done.  There is no logic for shutting the project down.