A Critical-Time-Point Approach to All-Start-Time Lagrangian Shortest Paths: A Summary of Results

  • Venkata M. V. Gunturi
  • Ernesto Nunes
  • KwangSoo Yang
  • Shashi Shekhar
Conference paper

DOI: 10.1007/978-3-642-22922-0_6

Volume 6849 of the book series Lecture Notes in Computer Science (LNCS)
Cite this paper as:
Gunturi V.M.V., Nunes E., Yang K., Shekhar S. (2011) A Critical-Time-Point Approach to All-Start-Time Lagrangian Shortest Paths: A Summary of Results. In: Pfoser D. et al. (eds) Advances in Spatial and Temporal Databases. SSTD 2011. Lecture Notes in Computer Science, vol 6849. Springer, Berlin, Heidelberg

Abstract

Given a spatio-temporal network, a source, a destination, and a start-time interval, the All-start-time Lagrangian Shortest Paths (ALSP) problem determines a path set which includes the shortest path for every start time in the given interval. ALSP is important for critical societal applications related to air travel, road travel, and other spatio-temporal networks. However, ALSP is computationally challenging due to the non-stationary ranking of the candidate paths, meaning that a candidate path which is optimal for one start time may not be optimal for others. Determining a shortest path for each start-time leads to redundant computations across consecutive start times sharing a common solution. The proposed approach reduces this redundancy by determining the critical time points at which an optimal path may change. Theoretical analysis and experimental results show that this approach performs better than naive approaches particularly when there are few critical time points.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2011

Authors and Affiliations

  • Venkata M. V. Gunturi
    • 1
  • Ernesto Nunes
    • 1
  • KwangSoo Yang
    • 1
  • Shashi Shekhar
    • 1
  1. 1.Computer Science and EngineeringUniversity of MinnesotaUSA