Showing 101 - 110 of 149
A recent study reported that the Macroscopic Fundamental Diagram of a medium size city exhibited a clockwise hysteresis loop on a day in which a major disturbance caused many drivers to use unfamiliar routes. It is shown below that, even in a perfectly symmetric network with uniform demand,...
Persistent link: https://www.econbiz.de/10008868417
Recent experimental work has shown that the average flow and average density within certain urban networks are related by a unique, reproducible curve known as the Macroscopic Fundamental Diagram (MFD). For networks consisting of a single route this MFD can be predicted analytically; but when...
Persistent link: https://www.econbiz.de/10008868451
A separate turn phase is often used on the approach leg to an intersections with heavy left turns. This wastes capacity on the approach because some of its lanes cannot discharge during its green phases. The paper shows that the problem can be eliminated by reorganizing traffic on all the lanes...
Persistent link: https://www.econbiz.de/10009023484
A simple model of traffic flow is used to analyze the spatio-temporal distribution of flow and density on closed-loop homogeneous freeways with many ramps, which produce inflows and allow outflows. As we would expect, if the on-ramp demand is space-independent then this distribution tends toward...
Persistent link: https://www.econbiz.de/10009023486
A macroscopic modeling approach is proposed for allocating a city’s road space among competing transport modes. In this approach, a city or neighborhood street network is viewed as a reservoir with aggregated traffic. Taking the number of vehicles (accumulation) in a reservoir as input,...
Persistent link: https://www.econbiz.de/10011130740
Simulations and field experiments in previous works suggest that a freeway’s general purpose lanes (those not dedicated to high occupancy vehicles) discharge vehicles from bottlenecks at an equal or higher average rate when one of the lanes is devoted to high occupancy vehicles than when...
Persistent link: https://www.econbiz.de/10011130750
This paper describes the network shapes and operating characteristics that allow a transit system to deliver a level of service competitive with that of the automobile. To provide exhaustive results for service regions of different sizes and demographics, the paper idealizes these regions as...
Persistent link: https://www.econbiz.de/10011130754
Traffic congestion is a growing problem in Nairobi, Kenya, resulting from rapidly increasing population and the crowding of motorized traffic onto a limited street network. This report includes analysis of the traffic conditions in Nairobi, the expected effects of further growth in demand, and a...
Persistent link: https://www.econbiz.de/10011130757
An earlier empirical study of San Francisco Bay Area freeways concluded that HOV lanes unfavorably affect freeway traffic by creating congestion. That study attributed the observed congestion to HOV lanes and tentatively recommended their elimination over the full lengths of the freeways it...
Persistent link: https://www.econbiz.de/10011130781
This paper shows that evacuation routes, such as a building’s stairwell or an urban freeway, may discharge inefficiently if left unmanaged, and that setting priority rules can speed up egress. Therefore, a simple control strategy is proposed. The strategy is decentralized and adaptive,...
Persistent link: https://www.econbiz.de/10011130787