Veri cation of Interlockings: from Control Tables to Ladder Logic Diagrams
نویسندگان
چکیده
Dependency relations between objects in a railway yard are tabulated in control tables. An interlocking, which guarantees validity of these dependencies, can be implemented in ladder logic. We transform a ladder logic diagram into a Boolean formula, so that validity of the dependencies in the control tables can be veri ed using a theorem prover. Time copies and invariants are added to the formula, to relate it more rmly to its ladder logic diagram. Program slicing is applied to reduce the size of the formula.
منابع مشابه
Verification of Interlockings: from Control Tables to Ladder Logic Diagrams
Dependency relations between objects in a railway yard are tabulated in control tables. An interlocking, which guarantees validity of these dependencies, can be implemented in ladder logic. We transform a ladder logic diagram into a Boolean formula, so that validity of the dependencies in the control tables can be verified using a theorem prover. Time copies and invariants are added to the form...
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