NBMK_hEART2017 TRANSP-OR TALK Nikolic, Marija Bierlaire, Michel Markov, Iliya Bondo, Romain Pedestrian multi-class speed-density relationship: evaluation of integrated and sequential approach 2017 6th Symposium of the European Association for Research in Transportation Faculty of Civil and Environmental Engineering, Technion, Haifa, Israel September 12, 2017