Nested Precedence Networks with Alternatives: Recognition, Tractability, and Models

  • Roman Barták
  • Ondřej Čepek
Part of the Lecture Notes in Computer Science book series (LNCS, volume 5253)

Abstract

Integrated modeling of temporal and logical constraints is important for solving real-life planning and scheduling problems. Logical constrains extend the temporal formalism by reasoning about alternative activities in plans/schedules. Temporal Networks with Alternatives (TNA) were proposed to model alternative and parallel processes, however the problem of deciding which activities can be consistently included in such networks is NP-complete. Therefore a tractable subclass of Temporal Networks with Alternatives was proposed. This paper shows formal properties of these networks where precedence constraints are assumed. Namely, an algorithm that effectively recognizes whether a given network belongs to the proposed sub-class is studied and the proof of tractability is given by proposing a constraint model where global consistency is achieved via arc consistency.

Keywords

temporal networks alternatives constraint models complexity 

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Copyright information

© Springer-Verlag Berlin Heidelberg 2008

Authors and Affiliations

  • Roman Barták
    • 1
  • Ondřej Čepek
    • 1
    • 2
  1. 1.Faculty of Mathematics and PhysicsCharles University in PraguePraha 1Czech Republic
  2. 2.Institute of Finance and AdministrationPraha 10Czech Republic

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