Traffic congestion

About: Traffic congestion is a research topic. Over the lifetime, 16826 publications have been published within this topic receiving 235654 citations. The topic is also known as: traffic jam & traffic snarl-up.

Urban peak traffic hour automobile transportation automatic route selection method

Abstract: The invention discloses an urban peak traffic hour automobile transportation automatic route selection method, belonging to the technical field of traffic transportation services. The method comprisesan urban real-time traffic flow information service platform, an electronic map, a GPS navigation module and an automatic route selection module, and the technical problem that an optimal transportation route is formulated according to the traffic congestion condition is solved. The system and the method have the advantages of city globality, vehicle performance and selection/adjustment real-timeperformance, the requirement for automatically selecting the route of the automobile in the urban peak traffic hour is met, the system and the method also have the advantages of being closer to the original driving habit of a driver, and have an experience effect of an old driver's driving.

Driving Up the Cost of Clean Air

Abstract: The internal combustion engine is a mixed blessing. The freedom of movement provided by cars and light trucks—minivans, SUVs, and pickups—is unprecedented. But these same vehicles also pose a major public health problem. It is not surprising, then, that strategies to mitigate the harmful side effects of personal transportation are a major topic of study. In 2002, car accidents killed nearly 43,000 and incapacitated another 356,000, according to the National Highway Traffic Safety Administration. Vehicle exhaust contributes to untold numbers of hospitalizations for asthma attacks and other health problems, while car-related pollution contributes to lung diseases and heart attacks. Cars and light trucks on American roads contribute slightly less than 4% of the world’s annual burden of greenhouse gases and about 20% of the U.S. burden. Each year, car- and truck-related congestion costs the United States $63 billion in lost time and wasted fuel, according to the Texas Transportation Institute’s 2004 Urban Mobility Report, and 5.6 billion gallons of gasoline are wasted by idling in traffic. Much controversy swirls in the debate over how best to mitigate the harmful side effects of automotive transportation. It is somewhat helpful to sharpen the debate by appealing to economic theory, although ideals usually become badly dented when they collide with politics. Some of these harmful side effects are what economists call “externalities,” or costs that are not incorporated into the market price. A motorist buying gasoline, for example, does not pay for the costs of the climate change or the air pollution that will result from burning that fuel, or the military cost of maintaining access to Persian Gulf oil. Externalities have obvious solutions: figure out their costs, and incorporate them into the price. The theoretically superior strategy would be to tax individual greenhouse gas emissions and to incorporate defense costs into the price of oil specifically from the Persian Gulf (although military spending, generally viewed as a fixed rather than variable cost, is usually excluded from computations of the optimal oil or gasoline tax). Accidents are arguably not externalities, because they are largely paid for through insurance. However, car insurance does not cover expenses such as fire and police department costs or costs related to death and pain/suffering. Furthermore, insurance is a lump-sum payment rather than a per-mile charge, so motorists likely do not consider accident costs when deciding how much to drive a given vehicle. Traffic congestion, a well-established result of motorization, is less ambiguous as an externality, although people endure part of the delays they help to create. But to the extent that accidents and congestion are externalities, they are externalities of driving, not of gasoline use, because cars can run on other fuels. As yet, determining the cost of fuel-based externalities is a primitive art, says Mark Delucchi, a research scientist at the Institute for Transportation Studies of the University of California, Davis. “The best estimates of virtually all important external costs—air pollution, noise, accidents, congestion, and oil importing—vary by about an order of magnitude,” he wrote in the spring 2000 issue of Access magazine. Delucchi advocates using these estimates to inform but not determine policy. A number of strategies have been suggested in the United States to reduce the problems created by automotive transportation. One strategy in particular—the corporate average fuel economy (CAFE) standards—has been around for several decades. The pros and cons of personal transportation and the controversy surrounding CAFE and other strategies demonstrate the need for careful thought—as well as the hazards that arise—when policy meets politics.

Modeling of freeway ramp merging process observed during traffic congestion

Abstract: This study's focus is on modeling vehicle acceleration-deceleration behavior during freeway and ramp maneuvers in congested traffic. Presented are methodologies for collecting field data, analyzing freeway merging behavior data and developing and calibrating ramp vehicle accelerating models. Substantial data were collected using videotape and image processing techniques. The entrance ramps in the Tokyo Metropolitan Expressway were used for comprehensive traffic surveys. The paper presents a theoretical framework for modeling the ramp driver acceleration-deceleration behavior. The methodology uses the stimuli-response psychophysical concept as a fundamental rule and is formulated as a modified form of the car-following models. The findings could serve future highway geometric design criteria revision, and the mathematical framework of the developed model may be appropriate to study more driver behavioral aspects of congested freeways.

Potential benefits of in-vehicle information systems in a real life freeway corridor under recurring and incident-induced congestion. in: conference record of papers presented at the first vehicle navigation and information systems conference, toronto, ontario, canada - september 11-13, 1989

Abstract: Optimal use of existing transportation facilities has become a major priority in congested urban areas. Providing real-time in-vehicle traffic information to drivers is one possibility of achieving this goal. This paper documents an initial attempt to ascertain the potential benefits of a real-time in-vehicle traffic information system under recurring and non-recurring congestion conditons.