Acta Geodaetica et Cartographica Sinica ›› 2014, Vol. 43 ›› Issue (11): 1190-1196.doi: 10.13485/j.cnki.11-2089.2014.0183

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Accessibility Analysis of Road Network Supported by Isochrone Model

HE Yakun, AI Tinghua,YU Wenhao   

  1. Wuhan University
  • Received:2013-12-06 Revised:2014-05-25 Online:2014-11-20 Published:2014-12-02
  • Contact: AI Tinghua E-mail:tinghua_ai@163.net

Abstract:

An isochrone is a visual representation of time accessibility which refers to a particular point in the road network. Features of road network and traffic conditions should be considered when generating isochrones. Accessibility rules can be found through analyzing the morphological features of isochrones. This article systematically studied the definition, characteristics and generation methods of isochrones. We proposed the flow method to generate isochrones, which was analogous to the process of water drop spreading along the wood texture. Accessibility expansion paths were obtained on the basis of the network rasterization model, considering unique constraints of isochrones extension, such as road conditions, moving criteria and time sections. Then we used the extending convex hull and angle bisector displacement to generate isochrones. Since the algorithm was based on field theory, we could flexibly load space constraints for any part of interested zones. This advantage made it convenient to generate real-time isochrones. Similar to extracting geomorphic traits from contour lines, we found accessibility rules by analyzing the arrangement form, density, bending form, bending direction and stretching direction of isochrones which was generated by the above approach. After that, we inferred accessibility rules.