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The congestion at on-ramps of motorways is due to too many vehicles wanting to merge onto the same lane. Ramp metering is usually used as control measure to influence the flows, but a variable speed limit can also have large consequences for the merging process. This paper discusses the change in lane distribution due to a VSL and explicitly considers the(More)
Nowadays, many vehicles are equipped with GPS navigation systems, that are accurate to approximately 10 meters. This is insufficient to determine the lane a vehicle is driving in. We introduce a new technique, Precise Point Positioning, which is able to get the accuracy of measurement down to approximately half a meter, without having to resort to expensive(More)
Since centralized control of urban networks with detailed modeling approaches is computationally complex and inefficient, hierarchical decentralized methods based on aggregate models are of great importance. In this paper, we use an aggregate modeling approach based on the macroscopic fundamental diagram (MFD), in order to find dynamic optimal routing(More)
Sags are segments of the road where there is a significant change in gradient from downhill to uphill in a short distance. Empirically, it has been observed that drivers do not compensate adequately for the changing grade resistance force at sags, which limits vehicle acceleration. As a consequence, congestion forms at sags. This paper proposes and compares(More)
This paper focuses on the derivation of analytical formulae to estimate the effective capacity at freeway merges. It extends previous works by proposing a generic framework able to account for a refined description of the physical interactions between upstream waves and downstream voids created by inserting vehicles within the merge area. The provided(More)
Modern Intelligent Transport Solutions can achieve improvement of the traffic flow at motorways. With lane-specific measurements and lane-specific control more measures are possible. Single Frequency Precise Point Positioning (PPP) is a newly developed technique to get a sub-meter accurate position from the signals of the Global Positioning System (GPS).(More)
Uphill sections have often been identified as capacity bottlenecks in freeway networks. One of the main reasons seems to be that drivers reduce speed when they reach the beginning of an uphill section. With high traffic demand, the deceleration of the first vehicle of a platoon can generate a flow disturbance that amplifies as it propagates upstream,(More)
Lane changes are important in quantifying traffic for both operational and planning purposes. Traditional in-lane loop detectors do not count lane changes; hence, historically, traffic engineers have estimated them using other data sources. This paper provides a method for estimating the number of lane changes based on observations of(More)
Many network-wide traffic management strategies based on the Macroscopic or Network Fundamental Diagram (NFD) have been developed in recent years. In this paper we investigate one of these strategies, namely feedback NFD-based perimeter control, which limits the rate at which vehicles are allowed to enter an urban region. The inflow limitation is imposed at(More)