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There are two problems associated with contraflow operations, namely, the lane configuration problem and the scheduling problem. The former determines the optimal lane reversing scheme for the operation while the latter decides the start time and the duration of contraflow. In this study, both problems are modelled under one bi-level programming model. The upper level problem gives the optimal lane configuration and schedule by minimising the total travel time of the study area, while the lower level is a traffic simulation model that can capture the response of drivers towards the network changes. A hybrid metaheuristic-traffic simulation methodology is suggested to solve the proposed model. An illustrative case study of Singapore arterial network is adopted as an example to test the effectiveness of the proposed model and algorithm. Results show that by considering these problems simultaneously, an overall optimal solution can be obtained compared with solving the problems individually. [ABSTRACT FROM AUTHOR]

Most automatic incident detection algorithms were successfully developed using loop-detector-based traffic measurements collected from their own localities. But their detection performances were not satisfactory when applied on data collected using a video-based detector system. The video-based detector system is gaining popularity as it was reported to be cost-effective, less prone to damage compared to loop detectors embedded in road pavement, and possesses surveillance capability. It is able to provide the homogeneity of traffic measurements with greater reliability in non-incident situations. In this study, a simple detection rule was used to develop algorithms that use video-based data for detecting lane-blocking incidents. A set of 96 incidents from Singapore's Central Expressway was used for calibrating these algorithms, with another 64 incidents for validation. Two single-station algorithms, named dual-variable (DV) and flow-based DV algorithms were developed. They have similar detection logic, but the latter includes a pre-incident traffic flow condition in its detection framework. On average, the flow-based DV algorithm outperformed the DV algorithm, and both proved to be effective techniques when compared to some existing loop-detector-based algorithms. [ABSTRACT FROM AUTHOR]

In heavy traffic flow conditions, vehicles have limited manouverability which affects the magnitude of response to incident-induced traffic disturbances and how fast changes in these traffic variables can signal the occurrence of an incident. Such characteristics are usually used to formulate a loop-based algorithm. A recent study reported that some existing algorithms were not able to maintain a desired level of effectiveness when these algorithms were used to detect incidents with a video-based detector system. Two new video-based automatic incident detection algorithms, the INdividual Detection Evaluation (INDE) and COmbined Detection Evaluation (CODE) algorithms were, therefore, developed for the detection of lane-blocking incidents in heavy traffic flow conditions using the Central Expressway in Singapore as a case study. The algorithms detect incident-induced traffic speed and occupancy disturbances differently: INDE processes information at each individual detector station and CODE processes information at two adjacent detector stations. Both algorithms outperformed existing algorithms commonly used in incident management systems. Of these algorithms, the INDE algorithm raised fewer false alarms and gave slightly faster incident warnings. However, its performance was relatively less consistent when applied to a validation database. [ABSTRACT FROM AUTHOR]

The congestion charging schemes in London and Singapore are compared and assessed in the light of guidelines set out in the Smeed Report, published by the UK Ministry of Transport in 1964, and their performance in reducing congestion and raising net revenue. The aim is to draw lessons for other towns and cities considering the introduction of congestion charging. One important result from Electronic Road Pricing in Singapore is that a per‐entry charge is more effective at reducing congestion than a per‐day charge. It is concluded that although Electronic Road Pricing in Singapore is more in line with the desirable properties outlined in the Smeed Report, both schemes are part of a wider package of transport policies, and that is probably the most important reason for their success. The main lesson for other towns and cities around the world considering the possibility of introducing congestion charging is that any such scheme ought to be accompanied by complementary measures that will provide motorists with a valid alternative to the car. [ABSTRACT FROM AUTHOR]

• A heterogeneous network with signalized and non-signalized intersections is modelled. • A traffic light control problem based on proposed macroscopic model is formulated. • The problem is converted to a mixed integer linear problem for computational benefit. • Simulations are shown to provide guidance for the design of an urban traffic system. In this paper, one type of heterogeneous traffic network, which consists of signalized intersections and non-signalized ones, is analyzed and modelled with a macroscopic model and logic constraints, which involves the evolution of the number of vehicles on each link and the leaving flow dynamics at each intersection. We propose a novel model describing the dynamic behaviors of such a system and the proposed model is validated via road tests in Singapore traffic network and simulations in VISSIM. A piecewise linear model is adopted to describe the traffic flow dynamics at each signalized intersection, while a platooning-like first-in-first-out (FIFO) model is proposed to depict the dynamics at each non-signalized intersection. A traffic light control problem for a heterogeneous traffic network is formulated based on the proposed macroscopic model as a mixed integer programming problem. Simulations indicate that the proposed optimal traffic control scheme could outperform the fixed-time traffic light control strategy and conventional actuated traffic light control scheme. Besides, we demonstrate potentials in developing a systematic planning approach on deciding which traffic intersections require signal control to ensure good traffic control performance. [ABSTRACT FROM AUTHOR]