Magic Loops and the Dynamic Controllability of Simple Temporal Networks with Uncertainty
نویسنده
چکیده
A Simple Temporal Network with Uncertainty (STNU) is a structure for representing and reasoning about temporal constraints and uncontrollable-but-bounded temporal intervals called contingent links. An STNU is dynamically controllable (DC) if there exists a strategy for executing its time-points that guarantees that all of the constraints will be satisfied no matter how the durations of the contingent links turn out. The fastest algorithm for checking the dynamic controllability of STNUs is based on an analysis of the graphical structure of STNUs. This paper (1) presents a new method for analyzing the graphical structure of STNUs, (2) determines an upper bound on the complexity of certain structures—the indivisible semi-reducible negative loops; (3) presents an algorithm for generating loops—the magic loops—whose complexity attains this upper bound; and (4) shows how the upper bound can be exploited to speed up the process of DC-checking for certain networks.
منابع مشابه
Magic Loops in Simple Temporal Networks with Uncertainty - Exploiting Structure to Speed Up Dynamic Controllability Checking
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تاریخ انتشار 2013