Safe and timely scenario switching in UML real-time projects

A reconfiguration management pattern for UML real-time projects inspired by the Specification PEARL methodology is defined. It is parameterised by defining the properties of its components as well as by defining how the software is mapped to the hardware architecture. The pattern itself is a UML representation of a Specification PEARL architectural specification, together with the definition of the initial and alternative configurations as well as of methods of switching between operation scenarios. The article includes the description of the UML pattern and its parameterisation, with the goal to obtain clearly specified operation scenarios with well-defined transitions among them. In order to achieve safe and timely operation, the pattern must provide a "safety shell" for all scenarios, i.e., enable their deterministic, temporally predictable operation, and transitions between them