In speaking about different groups of units, I have found it convenient to use the concept of a Set. I try to explain the different types of sets below.
- Available User Set (AVS): Units available to one user, if the solutions and features currently using these units can be unimplemented, hence freeing them for use for the new solution that is desired.
- Context Set (CS): A set of units that would allow many solutions in a specific context, for instance furniture, to be implemented. These units all possess characteristics that are usually required in a specific context.
- Delta Set (DS): The difference between two sets, for instance the user set minus the solutions set will give a delta set. If it is negative, a set would be missing.
- Free User Set (FUS): A user’s units that are currently not in use.
- General Set (GS): Units used in most solutions providing common functions.
- Hot Standby Set (HSS): Redundant units providing replacement units for units that seize to operate properly.
- Redundant Set (RS): Units that is left over when a solution is implemented using units from previous solutions and that cannot be released by the new solution as there is no place to store them.
- Solution Set(SSet): The necessary numbers and types of units for a particular solution.
- Sales Set (SaSet): The set bargained for in one transaction.
- Support Set (SupSet): A set of units needed during the implementation of a solution or feature, but not needed in normal operation of that solution.
- No Alternative Cost Set (NACS): A part of the free set. The potential in these units cannot be realized for some reason, so they can be used without cost.
- Missing Set (MSet): The units missing that need to be procured in order to implement a solution.
- User Set (USet): The units controlled by one user.
