2 research outputs found
Runtime Monitoring of Metric First-order Temporal Properties
We introduce a novel approach to the runtime monitoring of complex
system properties. In particular, we present an online algorithm for
a safety fragment of metric first-order temporal logic that
is considerably more expressive than the logics supported by prior
monitoring methods. Our approach, based on automatic structures,
allows the unrestricted use of negation, universal and existential
quantification over infinite domains, and the arbitrary nesting of
both past and bounded future operators. Moreover, we show how
to optimize our approach for the common case where
structures consist of only finite relations, over possibly infinite
domains. Under an additional restriction, we prove that the space
consumed by our monitor is polynomially bounded by the cardinality
of the data appearing in the processed prefix of the temporal
structure being monitored
Explicit Clock Temporal Logic in Timing Constraints for Real-Time Systems
A form of explicit clock temporal logic (called TLrt) useful in specifying timing constraints on controller actions, a real-time database (rtdb) items, and constraints in a real-time constraint base (rtcb), is presented. Timing as well as other forms of constraints are stored in the rtcb. A knowledge-based approach to ensure the integrity of information in an rtdb is given. The rtcb is realized as a logic program called Constrainer, which is a historyless integrity checker for a real-time database. The consistency and integrity issues for an rtcb and rtdb are investigated. The formal bases for a temporally complete rtdb and knowledgeably complete controller are presented. A partial TLrt specification of a knowledgeable controller for a Gas Burner is given. An illustration of a rtdb and rtcb in the context of the sample real-time system is also given