京都大学桂キャンパスCクラスター C1-312(C1棟会議室3)

Developing effective O-D flow estimation/updating using traffic counts: Results and research prospects

日時:    8月12日(金) 15:00~16:30
場所:    京都大学桂キャンパスCクラスター C1-312(C1棟会議室3)
講師:    Dr. Vittorio Marzano, Università degli studi di Napoli Federico II
題目:   Developing effective O-D flow estimation/updating using traffic counts: Results and research prospects
Abstact: The seminar describes the main results of research activities on origin-destination (o-d) flows updating based on traffic counts, carried out by the research group at the University of Naples (Italy). A key issue in o-d flows updating is the dimensionality of the problem: by means of laboratory experiments, o-d flow updating is shown effective generally only when the ratio between equations (i.e. independent counted link flows) and unknowns (i.e. o-d flows) is close to one.  To achieve such balance, a within-day quasi-dynamic o-d flow estimator from traffic counts is presented, under the assumption that o-d shares are constant across a reference period, whilst total flows leaving each origin vary for each sub-period within the reference period. The advantage of this approach over conventional within-day dynamic estimators is to reduce drastically the number of unknowns, given the same set of observed time-varying traffic counts. The realism of the quasi-dynamic assumption and the theoretical and operational properties of the proposed quasi-dynamic estimator are discussed and tested on the real test site of A4-A23 motorways in North-Eastern Italy. Another possibility to balance unknowns and equations in o-d flows updating is to reduce the number of traffic zones in the study area, being the number of o-d flows proportional to the square of the number of traffic zones. Thus, an innovative optimization method for designing traffic zones to support o-d flows estimation/updating and relevant link flows estimation is also presented, and applied to a real case study in the Metropolitan Area of Napoli (Italy).
About the speaker: Vittorio Marzano is tenure-track assistant professor at the University of Naples Federico II (Italy), where he teaches Freight and logistics. He holds a PhD in Transport Engineering from the University of Napoli (2006) and an executive course in Supply chain management and distributive logistics from the Business School of the Politecnico di Milano (2010). He collaborates with many universities and research centres worldwide, including the Intelligent Transportation Systems lab of the MIT (Boston, USA) and the Singapore-MIT alliance for research and technology (Singapore). His research interests cover various areas of transport engineering: freight modelling and policy-making, discrete choice modelling, o-d flow estimation/updating, network sensors location, city logistics. Research results are published in 20 journal papers and more than 60 conference proceedings. He has participated to more than 20 national/international research projects. He is also consultant in transport projects in Italy and abroad, and an external expert of the Italian Ministry of Transport and Infrastructures.