Congestion management in traffic-light intersections via Infinitesimal Perturbation Analysis

We present a flow-control technique in traffic-light intersections, aiming at regulating queue lengths to given reference setpoints. The technique is based on multivariable integrators with adaptive gains, computed at each control cycle by assessing the IPA gradients of the plant functions. Moreover, the IPA gradients are computable on-line despite the absence of detailed models of the traffic flows. The technique is applied to a two-intersection system where it exhibits robustness with respect to modeling uncertainties and computing errors, thereby permitting us to simplify the on-line computations perhaps at the expense of accuracy while achieving the desired tracking. We compare, by simulation, the performance of a centralized, joint two-intersection control with distributed control of each intersection separately, and show similar performance of the two control schemes for a range of parameters

Blackspot Location and Recommendation to Reduce Number and Severity of Accidents on Purbaleunyi Toll Road

Toll roads, as land transportation infrastructure, have an important role in Indonesia. With a high number of road crashes in Indonesia, with about 40,000 people die on the road each year, the determination of blackspot locations is crucial. The aim of this study is to analyze blackspot location on a toll road in Indonesia and, furthermore, to provide recommendations in order to reduce number and severity of accident. A case study is carried out on a toll road, named Purbaleunyi Toll Road, in West Java. Accident rate value and UCL method are used in this study to determine blackspot locations. The results indicated that there are many blackspot locations along the toll road and recommended solutions provided are adherence to traffic regulation, adherence to vehicle worthiness,dissemination of road safety importance to road users, and the implementation of blackspot treatments continuously

Research Synthesis for the California Zero Traffic Fatalities Task Force

This research synthesis consists of a set of white papers that jointly provide a review of research on the current practicefor setting speed limits and future opportunities to improve roadway safety. This synthesis was developed to inform thework of the Zero Traffic Fatalities Task Force, which was formed in 2019 by the California State Transportation Agencyin response to California Assembly Bill 2363 (Friedman). The statutory goal of the Task Force is to develop a structured,coordinated process for early engagement of all parties to develop policies to reduce traffic fatalities to zero. Thisreport addresses the following critical issues related to the work of the Task Force: (i) the relationship between trafficspeed and safety; (ii) lack of empirical justification for continuing to use the 85th percentile rule; (iii) why we need toreconsider current speed limit setting practices; (iv) promising alternatives to current methods of setting speed limits;and (v) improving road designs to increase road user safety

Evaluation of the Wadden Sea Particularly sensitive Sea Area. On behalf of the Common Wadden Sea Secretariat.

The purpose of this document is to present the high level outcomes for the evaluation of the effectiveness of the Wadden Sea PSSA, seven years after its designation by the IMO. Key changes with regard to IMO and EU shipping policy are identified and described, followed by a review of ‘expert’ opinion focused on the issues relating to PSSAs. The development of an evaluative framework and the resulting findings are introduced and discussed in context. Using existing data against this evaluative framework we conclude that six key elements require action in order to fully describe the efficacy of the designation, and our recommendations to address these concerns are presented.<br/