Highway Capacity Manual改訂の動向--テイラ-教授の講演より

Historically, most demographic data for states and substate areas were collected from the long version of the decennial census questionnaire. A “snapshot” of the characteristics of the population on the April 1 census date was available once every 10 years. The long form of the decennial census has been replaced by the American Community Survey (ACS) that has been conducted on an ongoing basis for the entire country since 2005. Instead of a snapshot in which all of the data are gathered at one time, the ACS aggregates data collected over time, making the results more difficult to interpret. However, the ACS data are updated annually.

A practical guide to the American Community Survey (3-year estimates)

Transportation research. part c, emerging technologies

Transportation Networks. Optimality. Cost Functions. Deterministic User Equilibrium Assignment. Stochastic User Equilibrium Assignment. Trip Table Estimation. Network Reliability. Network Design. Conclusions. References. Index.

Transportation network analysis

This paper develops a novel linear programming formulation for autonomous intersection control (LPAIC) accounting for traffic dynamics within a connected vehicle environment. Firstly, a lane based bi-level optimization model is introduced to propagate traffic flows in the network, accounting for dynamic departure time, dynamic route choice, and autonomous intersection control in the context of system optimum network model. Then the bi-level optimization model is transformed to the linear programming formulation by relaxing the nonlinear constraints with a set of linear inequalities. One special feature of the LPAIC formulation is that the entries of the constraint matrix has only {−1, 0, 1} values. Moreover, it is proved that the constraint matrix is totally unimodular, the optimal solution exists and contains only integer values. It is also shown that the traffic flows from different lanes pass through the conflict points of the intersection safely and there are no holding flows in the solution. Three numerical case studies are conducted to demonstrate the properties and effectiveness of the LPAIC formulation to solve autonomous intersection control.

A linear programming formulation for autonomous intersection control within a dynamic traffic assignment and connected vehicle environment

This paper proposes a continuum model based on a three-dimensional flow-concentration surface for multi-class traffic. The model assumes that the flow of any vehicle class is a function of the class density as well as the fraction of road area occupied by other vehicle classes. By considering occupancy of road area instead of lane occupancy, the model effectively describes traffic flow that does not follow lane discipline. The propagation speed of small disturbance (PSSD), conventionally defined from the two-dimensional flow–density relationship, is reformulated for each class using a three-dimensional flow–concentration surface. Using the proposed PSSD and a speed–area occupancy (speed- A O ) relationship, a second-order continuum model for multi-class traffic is formulated. The speed– A O relationship captures class-specific congestion and replicates the gap-filling behaviour commonly observed in lane-indisciplined traffic. Properties of the proposed model are validated theoretically where possible, and through numerical simulation when theoretical derivations are cumbersome. Numerical simulation of the proposed multi-class traffic model replicates field-observed phenomena such as shockwaves and rarefaction waves, local cluster effect, and gap-filling behaviour. Finally, the model is calibrated using field traffic data collected on a road section with bottleneck, and is found to replicate class-wise vehicle flows and speeds, and stop-and-go phenomena.

Multi-class traffic flow model based on three dimensional flow–concentration surface

The increasing challenges in managing and operating transportation systems have behooved transportation agencies to consider innovative alternative technology solutions to improve transportation system performance. The goal of this project was to conduct a comprehensive survey and assessment of the emerging and promising technologies that are likely to impact transportation performance in the New York Metropolitan Transportation Council (NYMTC) region. A key purpose of this was to develop a document which would serve as a "one-stop shop" for emerging technology that may be considered for implementation by the different transportation agencies in the NYMTC region. The study was divided into the following six tasks: (1) Comprehensive Literature Review; (2) Initial List of Emerging Technologies; (3) Screening of Emerging Technologies; (4) Shortlist of Emerging Technologies; (5) Assessment of Shortlisted Technologies; and (6) Conference and Final Report. The technologies examined fall into the following categories: congestion reduction and management; safety and security; and energy and environment. The findings from this project are contained in this final report.

A Comprehensive Survey of Emerging Technologies for New York Metropolitan Area

Ride-hailing services have grown in cities around the world. There are, however, few studies and even fewer publicly available data sources that provide a basis to understand and quantify changes i...

Modeling the Evolution of Ride-Hailing Adoption and Usage: A Case Study of the Puget Sound Region

The New York Metropolitan Transportation Council (NYMTC) funded a project executed by a team from Rensselaer Polytechnic Institute to perform a comprehensive scan of emerging technologies that could affect transportation in the New York City metropolitan region in the next 20 years. A primary goal of the technology scan is to develop a document that serves as a one-stop shop for emerging technology that may be considered for implementation by different transportation agencies in the NYMTC region. This paper briefly presents the different emerging technologies, their characteristics, and important results from the project pertaining to congestion reduction and safety objectives.

Comprehensive Review of Emerging Technologies for Congestion Reduction and Safety

Multi-class traffic flow modelling has various approaches several of which have focused on analytical proofs. A key limitation in this field of research is the limited field data applications. This study proposes a speed-gradient-based multi-class second-order model and shows its application to three different road sections, a mid-block section, a section with a bottleneck, and a section with a signal at the end, in Chennai, India. The model captures the congestion formation and dissipation phenomena well and could predict outflow and speed fluctuations generally observed in the field scenarios accurately. The prediction of traffic flow dynamics by the proposed model is also observed to be better when compared with two existing higher-order multi-class models. Â© The Institution of Engineering and Technology 2020

https://ietresearch.onlinelibrary.wiley.com/doi/pdf/10.1049/iet-its.2019.0583

Gitakrishnan Ramadurai

Papers

Multi-class traffic flow model based on three dimensional flow–concentration surface

A Comprehensive Survey of Emerging Technologies for New York Metropolitan Area

Modeling the Evolution of Ride-Hailing Adoption and Usage: A Case Study of the Puget Sound Region

Comprehensive Review of Emerging Technologies for Congestion Reduction and Safety

Field data application of a non-lane-based multi-class traffic flow model