Constraints

Constraints are used in two ways:

• Preventive constraints, define the scope of automation. For example, an automatic pilot may be used to ensure that an airplane will flight according to the rules defining normal flight.
• Alerting constraints, define the scope of expected events. For example, in the process industry, deviations from safety ranges might result in accident, as was the case with the Bhopal disaster.

Constraint definition

Constraints are valid in specific context, called the Scenario.