Open AccessSIGNIFICANCE OF INCORPORATING HETEROGENEITY IN A NON-CONTINUUM MACROSCOPIC MODEL FOR DENSITY ESTIMATION
Author(s) -
Ajitha Thankappan,
Lelitha Vanajakshi,
Shankar C. Subramanian
Publication year - 2014
Publication title -
transport
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.437
H-Index - 31
eISSN - 1648-4142
pISSN - 1648-3480
DOI - 10.3846/16484142.2014.928789
Subject(s) - kalman filter , computer science , traffic flow (computer networking) , traffic congestion , econometrics , microscopic traffic flow model , estimation , process (computing) , density estimation , spatial heterogeneity , road traffic , mathematical optimization , statistics , transport engineering , mathematics , traffic generation model , engineering , real time computing , artificial intelligence , computer security , systems engineering , operating system , ecology , estimator , biology
The heterogeneity of traffic and the lack of lane discipline on the roads in India and other developing countries add complexity to the analysis and modeling of traffic. It is generally believed that it is important to take heterogeneity into account in traffic modeling. The aim of the present study is to check the validity of this assumption by analyzing the effect of incorporating heterogeneity in a macroscopic level traffic flow analysis. The application considered is real-time congestion analysis on Indian roads. Traffic density is considered as the congestion indicator. The measurement of density is difficult since it is a spatial parameter. It is usually estimated from other traffic parameters that can be readily measured using available sensors. A model-based estimation scheme using Kalman filtering has been employed to estimate traffic density. A non-continuum macroscopic model was attempted based on the lumped parameter approach. All the traffic variables were quantified without considering traffic lanes in order to take into account the lack of lane discipline. The effect of heterogeneity has been studied by incorporating static values of Passenger Car Units (PCU), dynamic values of Two Wheeler Units (TWU) and considering different classes of vehicles explicitly in the modeling process. The proposed estimation schemes without and with heterogeneity have been compared. The results have been corroborated using data collected from a road stretch in Chennai, India. The study shows that the significance of incorporating heterogeneity into the modeling of mixed traffic at the macroscopic level was not very significant.