Controllability refers to

*"* ... *the ability to maintain a stable process, while handling disturbances and short-term variations to the process. According to our choice of definition, it also includes being able to maintain a stable process during transition from one operating scenario to another."*

Feasibility of startup/shutdown transitions refers to

*"* ... *the ability to start up or shut down the process in a controlled and safe manner. Due to the special characteristics of startup*/*shutdown transitions, this is important to consider separately, although it is essentially included in the afore-mentioned definition of controllability."*
