Combining RCC-8 with qualitative direction calculi: algorithms and complexity

  • Authors:

  • Weiming Liu;Sanjiang Li;Jochen Renz

  • Affiliations:

  • State Key Laboratory of Intelligent Technology and Systems, TNLIST, Department of Computer Science and Technology, Tsinghua University, China;State Key Laboratory of Intelligent Techn. and Systems, TNLIST, Dept. of Comp. Science and Techn., Tsinghua Univ., China and Centre for Quantum Computation and Intelligent Systems, Fac. of Eng. an ...;Research School of Information Sciences and Engineering, The Australian National University, Australia

  • Venue:
  • IJCAI'09 Proceedings of the 21st international jont conference on Artifical intelligence
  • Year:
  • 2009

Quantified Score

Hi-index 0.00

Visualization

Abstract

Increasing the expressiveness of qualitative spatial calculi is an essential step towards meeting the requirements of applications. This can be achieved by combining existing calculi in a way that we can express spatial information using relations from both calculi. The great challenge is to develop reasoning algorithms that are correct and complete when reasoning over the combined information. Previous work has mainly studied cases where the interaction between the combined calculi was small, or where one of the two calculi was very simple. In this paper we tackle the important combination of topological and directional information for extended spatial objects. We combine some of the best known calculi in qualitative spatial reasoning (QSR), the RCC8 algebra for representing topological information, and the Rectangle Algebra (RA) and the Cardinal Direction Calculus (CDC) for directional information. Although CDC is more expressive than RA, reasoning with CDC is of the same order as reasoning with RA. We show that reasoning with basic RCC8 and basic RA relations is in P, but reasoning with basic RCC8 and basic CDC relations is NP-Complete.