Stauner, ThomasPretschner, AlexanderPéter, IstvánEvans, AndyFrance, Robert B.Moreira, Ana M. D.Rumpe, Bernhard2020-01-072020-01-0720013-88579-335-0https://dl.gi.de/handle/20.500.12116/30857This paper presents HyROOM, a proposal for an extension of UML-like languages by continuous activities for the specification of mixed discrete-continuous, or hybrid, systems. Is is implemented in a CASE tool prototype based on the Real-time Object Oriented Modeling methodology. All vital parts of HyROOM's operational simulation semantics are mapped into HyCharts, a formal framework for hybrid systems. All essential concepts are discussed along the lines of parts of an industrial case study, a wire stretching plant. The semantics is the basis for validation and refinement techniques.enText/Conference Paper1617-5468