Activation-oriented specification of real-time systems

  • Vered Gafni
  • Amiram Yehudai
  • Yishai A. Feldman
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 863)


We present MASS, a declarative language for specifying the reactive behavior of real-time systems. The basic primitive of the language is the task, which is the interface between the reactive and sequential aspects of the specification. The purely computational meaning of a task (as an I/O transformation) is given outside MASS using standard specification languages for sequential computations. The reactive aspects of real-time systems are expressed in MASS through causal and temporal relations between events that signal task terminations. Hierarchical systems are obtained by refining tasks, specifying them as sub-systems in MASS.

MASS is given a formal semantics in a trace model augmented with explicit representation of causes. A synchronous execution model conforming with the formal semantics makes MASS specifications executable. A development system based on this model allows both simulation of (possibly incomplete) specifications and the generation of complete target applications (given, code for the sequential computations of tasks). We have successfully used MASS in a case study involving several robots and a complex conveyer system.


Basic Event Response Task System Task Reactive Behavior Environment Task 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1994

Authors and Affiliations

  • Vered Gafni
    • 1
  • Amiram Yehudai
    • 1
  • Yishai A. Feldman
    • 1
  1. 1.The Institute of Computer Science The Raymond and Beverly Sackler Faculty of Exact SciencesTel-Aviv UniversityTel-AvivIsrael

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