Rail transit with its high passenger capacity and high efficiency has become one of the preferred alternatives to automobile travel. This is evident in the increasing patronage of rail travel especially in urban areas. As a result, many railway stations experience high levels of pedestrian congestion especially during the morning and afternoon peak periods. Traditional design and evaluation pro...

Rail transit is developing rapidly in major cities of China and has become a key component of urban transport. Nevertheless, the security and reliability in operation are significant issues that cannot be neglected. In this paper, the network and station vulnerabilities of the urban rail transit system were analyzed based on complex network and graph theories. A vulnerability evaluation model w...

Urban mass transit such as metro plays a significant role in transportation in metropolitan areas. Its most notable usage is the morning commute situation. It is known that such transit can be delayed due to congestion under excessive passenger demand. However, there are no tractable models of transit systems considering physics of its delay and congestion. It makes difficult to obtain realisti...

Exposure to airborne pollution has substantial adverse health consequences. A recent World Health Organization (WHO) study has estimated that urban air pollution accounts for 6.4 million years of life lost worldwide annually (Cohen et al. 2004). Many harmful pollutants are emitted by automobiles. For example, Currie and Walker (2011) estimate that prenatal exposure to traffic congestion alone r...

Commuter rail systems are widely regarded as an effective transportation alternative to reduce energy consumption and emissions in large urban areas. Use of commuter rail systems in the United States is on the rise, with annual ridership increasing by 28 percent between 1997 and 2007 [1]. With growing concerns about the sustainability and environmental impacts of transportation, modal energy ef...

As a sustainable means of public transportation, urban rail transit system undergoes rapid expansion in China. How to provide a safe and reliable service has been the subject of growing attention in this context. However, such work is challenging because rail transit systems are quite vulnerable and influenced by a set of interacting factors. Studying these vulnerability factors will contribute...

Currently most modern dc rapid transit systems around the world use running rails or a negative rail as the negative return circuit for the dc traction current. These rails are intentionally kept ungrounded from ground (earth) by using insulating material between the rail and earth to minimize dc stray current. This configuration of return current rail develops varying voltage with respect to g...

Passenger flow estimation of transit systems is essential for new decisions about additional facilities and feeder lines. For increasing the efficiency of an existing transit line, stations which are insufficient for trip production and attraction should be examined first. Such investigation supports decisions for feeder line projects which may seem necessary or futile according to the findings...

This paper presents a model that calculates the social welfare benefits of using additional subsidy to reduce fare levels or improve service levels of public transit in Chicago. The model differentiates between the effects in peak and off-peak periods for both bus and rapid rail service. The potential welfare benefits of transit improvements accrue to several different groups of people: (1) exi...