Processing Time Relationships
Use
A relationship with a minimum or maximum time interval can exist between two activities. (You define time relationships in the source of supplyfor in-house production.) At the start of the optimization run, the system evaluates the relationships between the activities and then determines the possible scheduling dates/times for the activities.
Relationship between two non-fixed activities
During optimization, the system must always adhere to the relationship between two non- fixed activities; they represent a hard constraint . The system is not allowed to drop below the minimum interval, and the maximum interval must not be exceeded.
Relationship between a fixed and a non-fixed activity
Using the relationship between a non-fixed activity and a fixed activity, the system determines the earliest or the latest start or finish dates/times for the non-fixed activity. These dates represent hard or soft constraints for the optimization as follows:
Earliest start or finish dates/times are a hard constraint for the optimization.
By default, latest start or finish dates/times are soft constraints that the system is allowed to violate. These delays can be minimized during optimization.
The following table provides a summary of the dates/times defined by a relationship to a fixed activity. The relationship goes from the first activity to the second.
First activity
Second activity
Type of interval
Date/times defined by relationship
Fixed
Non-fixed
Maximum interval
Latest start or finish date/time
Fixed
Non-fixed
Minimum interval
Earliest start or finish date/time
Non-fixed
Fixed
Maximum interval
Earliest start or finish date/time
Non-fixed
Fixed
Minimum interval
Latest start or finish date/time