International Conference on Agents and Artificial Intelligence

Agents and Artificial Intelligence pp 243-261 | Cite as

Revisiting Classical Dynamic Controllability: A Tighter Complexity Analysis

  • Mikael Nilsson
  • Jonas Kvarnström
  • Patrick Doherty
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 8946)

Abstract

Simple Temporal Networks with Uncertainty (STNUs) allow the representation of temporal problems where some durations are uncontrollable (determined by nature), as is often the case for actions in planning. It is essential to verify that such networks are dynamically controllable (DC) – executable regardless of the outcomes of uncontrollable durations – and to convert them to an executable form. We use insights from incremental DC verification algorithms to re-analyze the original, classical, verification algorithm. This algorithm is the entry level algorithm for DC verification, based on a less complex and more intuitive theory than subsequent algorithms. We show that with a small modification the algorithm is transformed from pseudo-polynomial to \(O(n^4)\) which makes it still useful. We also discuss a change reducing the amount of work performed by the algorithm.

Keywords

Temporal networks Dynamic controllability 

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Copyright information

© Springer International Publishing Switzerland 2015

Authors and Affiliations

  • Mikael Nilsson
    • 1
  • Jonas Kvarnström
    • 1
  • Patrick Doherty
    • 1
  1. 1.Department of Computer and Information ScienceLinköping UniversityLinköpingSweden

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