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Reasoning the Causality of City Sprawl, Traffic Congestion, and Green Land Disappearance in Taiwan Using the CLD Model

Chen, Mei-Chih; Chang, Kaowen
Fonte: MDPI Publicador: MDPI
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
46.68%
Many city governments choose to supply more developable land and transportation infrastructure with the hope of attracting people and businesses to their cities. However, like those in Taiwan, major cities worldwide suffer from traffic congestion. This study applies the system thinking logic of the causal loops diagram (CLD) model in the System Dynamics (SD) approach to analyze the issue of traffic congestion and other issues related to roads and land development in Taiwan’s cities. Comparing the characteristics of development trends with yearbook data for 2002 to 2013 for all of Taiwan’s cities, this study explores the developing phenomenon of unlimited city sprawl and identifies the cause and effect relationships in the characteristics of development trends in traffic congestion, high-density population aggregation in cities, land development, and green land disappearance resulting from city sprawl. This study provides conclusions for Taiwan’s cities’ sustainability and development (S&D). When developing S&D policies, during decision making processes concerning city planning and land use management, governments should think with a holistic view of carrying capacity with the assistance of system thinking to clarify the prejudices in favor of the unlimited developing phenomena resulting from city sprawl.

Evaluation of the Public Health Impacts of Traffic Congestion: A Health Risk Assessment

Levy, Jonathan Ian; Buonocore, Jonathan James; von Stackelberg, Katherine Ellen
Fonte: BioMed Central Publicador: BioMed Central
Tipo: Artigo de Revista Científica
EN_US
Relevância na Pesquisa
46.88%
Background: Traffic congestion is a significant issue in urban areas in the United States and around the world. Previous analyses have estimated the economic costs of congestion, related to fuel and time wasted, but few have quantified the public health impacts or determined how these impacts compare in magnitude to the economic costs. Moreover, the relative magnitudes of economic and public health impacts of congestion would be expected to vary significantly across urban areas, as a function of road infrastructure, population density, and atmospheric conditions influencing pollutant formation, but this variability has not been explored. Methods: In this study, we evaluate the public health impacts of ambient exposures to fine particulate matter (PM2.5) concentrations associated with a business-as-usual scenario of predicted traffic congestion. We evaluate 83 individual urban areas using traffic demand models to estimate the degree of congestion in each area from 2000 to 2030. We link traffic volume and speed data with the MOBILE6 model to characterize emissions of PM2.5 and particle precursors attributable to congestion, and we use a source-receptor matrix to evaluate the impact of these emissions on ambient PM2.5 concentrations. Marginal concentration changes are related to a concentration-response function for mortality...

TIME-ANTS: An innovative temporal and spatial ant-based vehicular routing mechanism

Doolan, Ronan; Muntean, Gabriel-Miro
Fonte: IEEE Computer Society Publicador: IEEE Computer Society
Tipo: info:eu-repo/semantics/conferenceObject; all_ul_research; ul_published_reviewed
ENG
Relevância na Pesquisa
46.7%
peer-reviewed; Increasing amounts of time is wasted due to traffic congestion in both developed and developing countries. This has severe negative effects, including drivers stress due to increased time pressure, reduced usage efficiency of trucks and other commercial vehicles, and increased gas emissions--responsible for climate change and air pollution affecting population health in densely populated areas. As existing centralized approaches were neither efficient, nor scalable, there is a need for alternative approaches. Social insects provide many solutions for dealing with decentralized problems. For instance ants choose their routes based on pheromones left by previous ants. However, Ant Colony Optimization is not directly applicable to vehicle routing, as routing the vehicles to the same road would cause traffic congestion. Yet, the traffic is broadly similar from work- to work-day. This paper introduces an ant-colony optimization-based algorithm called Time-Ants. Time-Ants considers that an amount of “pheromone” or a traffic rating is assigned to each road at any given time in the day. Using an innovative algorithm the vehicle’s routes are chosen based on these traffic ratings, aggregated in time. After several iterations this results in a global optimum for the traffic system. Bottlenecks are identified and avoided by machine learning. Time-Ants outperforms another leading algorithm by up to 19% in terms of percentage of vehicles to reach the destination within a given time-frame.

A hybrid vehicular re-routing strategy with dynamic time constraints for road traffic congestion avoidance

Wang, Shen; Djahel, Soufiene; McManis, Jennifer
Fonte: University of Limerick Publicador: University of Limerick
Tipo: info:eu-repo/semantics/conferenceObject; all_ul_research; ul_published_reviewed
ENG
Relevância na Pesquisa
46.74%
peer-reviewed; Nowadays, the rapid rise of the number of vehicles on the roads has led to several challenging problems for road authorities, such as traffic congestion, increasing number of accidents and air pollution. According to recent statistics, road traffic jam leads to a huge economic loss due to the increasing delay on the roads and the extra fuel consumption. Intelligent Transportation System (ITS) provides a promising framework to alleviate the congestion on the roads. However, a lot of work needs to be done to improve its efficiency, such as in the area of vehicles re-routing strategies. The main focus of this paper is on designing novel vehicles re-routing strategy to reduce the traffic congestion in urban areas. The proposed strategy is a hybrid approach which takes full advantage of both exact and heuristic algorithms and meets the requirements of dynamic time constraints of real road traffic scenarios. The next step of our work is to evaluate the performance of our strategy and compare it with the existing algorithms based on several metrics and under a benchmark of road topologies and traffic scenarios.

An Analysis of Various Policy Instruments to Reduce Congestion, Fuel Consumption and CO2 Emissions in Beijing

Anas, Alex; Timilsina, Govinda R.; Zheng, Siqi
Fonte: Banco Mundial Publicador: Banco Mundial
Relevância na Pesquisa
57.02%
Using a nested multinomial logit model of car ownership and personal travel in Beijing circa 2005, this paper compares the effectiveness of different policy instruments to reduce traffic congestion and CO2 emissions. The study shows that a congestion toll is more efficient than a fuel tax in reducing traffic congestion, whereas a fuel tax is more effective as a policy instrument for reducing gasoline consumption and emissions. An improvement in car efficiency would also reduce congestion, fuel consumption, and CO2 emissions significantly; however, this policy benefits only richer households that own a car. Low-income households do better under the fuel tax policy than under the efficiency improvement and congestion toll policies. The congestion toll and fuel tax require the travel cost per mile to more than triple. The responsiveness of aggregate fuel and CO2 are, approximately, a 1 percent drop for each 10 percent rise in the money cost of a car trip.

Pricing Externalities from Passenger Transportation in Mexico City

Parry, Ian W. H.; Timilsina, Govinda R.
Fonte: Banco Mundial Publicador: Banco Mundial
Relevância na Pesquisa
46.98%
The Mexico City Metropolitan Area has been suffering severely from transportation externalities such as accidents, air pollution, and traffic congestion. This study examines pricing instruments to reduce these externalities using an analytical and numerical model. The study shows that the optimal levels of a gasoline tax and a congestion toll on automobiles could generate social benefits, measured in terms of welfare gain, of US$132 and US$109 per capita, respectively, through the reduction of externalities. The largest component of the welfare gains comes from reduced congestion, followed by local air pollution reduction. The optimal toll and tax would, however, double the cost of driving and could be politically sensitive. Still, more than half of those welfare gains could be obtained through a more modest tax or toll, equivalent to $1 per gallon of gasoline. The welfare gains from reforming the pricing of public transportation are small relative to those from reforming the taxation of automobiles. Although the choice among travel modes depends on specific circumstances...

Impacts of Policy Instruments to Reduce Congestion and Emissions from Urban Transportation : The Case of São Paulo, Brazil

Anas, Alex; Timilsina, Govinda R.
Fonte: Banco Mundial Publicador: Banco Mundial
Relevância na Pesquisa
56.94%
This study examines impacts on net social benefits or economic welfare of alternative policy instruments for reducing traffic congestion and atmospheric emissions in São Paulo, Brazil. The study shows that expanding road networks, subsidizing public transit, and improving automobile fuel economy may not be as effective as suggested by economic theories because these policies could cause significant rebound effects. Although pricing instruments such as congestion tolls and fuel taxes would certainly reduce congestion and emissions, the optimal level of these instruments would steeply increase the monetary cost of travel per trip and are therefore politically difficult to implement. However, a noticeable finding is that even smaller tolls, which are more likely to be politically acceptable, have substantial benefits in terms of reducing congestion and emissions. Among the various policy instruments examined in the study, the most socially preferable policy option for São Paulo would be to introduce a mix of congestion toll and fuel taxes on automobiles and use the revenues to improve public transit systems.

Fiscal Policy Instruments for Reducing Congestion and Atmospheric Emissions in the Transport Sector : A Review

Timilsina, Govinda R.; Dulal, Hari B.
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Relevância na Pesquisa
56.98%
This paper reviews the literature on the fiscal policy instruments commonly used to reduce transport sector externalities. The findings show that congestion charges would reduce vehicle traffic by 9 to 12 percent and significantly improve environmental quality. The vehicle tax literature suggests that every 1 percent increase in vehicle taxes would reduce vehicle miles by 0.22 to 0.45 percent and CO2 emissions by 0.19 percent. The fuel tax is the most common fiscal policy instrument; however its primary objective is to raise government revenues rather than to reduce emissions and traffic congestion. Although subsidizing public transportation is a common practice, reducing emissions has not been the primary objective of such subsidies. Nevertheless, it is shown that transport sector emissions would be higher in the absence of both public transportation subsidies and fuel taxation. Subsidies are also the main policy tool for the promotion of clean fuels and vehicles. Although some studies are very critical of biofuel subsidies...

Demand Side Instruments to Reduce Road Transportation Externalities in the Greater Cairo Metropolitan Area

Parry, Ian W.H.; Timilsina, Govinda R.
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
EN_US
Relevância na Pesquisa
47%
Economically efficient prices for the passenger transportation system in the Greater Cairo Metropolitan Area would account for broader societal costs of traffic congestion and accidents, and local and global pollution. A $2.20 per gallon gasoline tax (2006 US$) would be economically efficient, compared with the current subsidy of $1.20 per gallon. Removal of the existing subsidy alone would achieve about three-quarters of the net benefits from subsidy elimination and the tax. Per-mile tolls could target congestion and accident externalities more efficiently than fuel taxes, although they are not practical at present. A combination of $0.80 per gallon gasoline tax to address pollution (versus $2.20 without tolls), and $0.12 and $0.19 tolls per vehicle mile on automobiles and microbuses, respectively, to address traffic congestion and accident externalities (versus $0.22 without fuel taxes) would be most efficient. Current public bus and rail subsidies are relatively close to efficient levels in the absence of such policies; however, if automobile and microbus externalities were fully addressed through more efficient pricing, optimal subsides to public transit would be smaller than current levels.

Korea’s Leap Forward in Green Transport

Lee, Changgi; Sung, Nak Moon; Choi, Sang Dae; Yi, Eun Joo Allison; Lee, Sangjoo
Fonte: World Bank Group, Washington, DC Publicador: World Bank Group, Washington, DC
Tipo: Brief
EN_US
Relevância na Pesquisa
46.79%
Megacities in developing countries suffer from serious traffic congestion, high levels of greenhouse gas (GHG) emissions, and heavy air pollution. These urban areas face a stark dilemma: economic expansion attracts more people and vehicles; but the resulting traffic and pollution hinder further growth while reducing the quality of life for their citizens. Not long ago, Seoul faced a similar conundrum. Choked with pollution and traffic jams, it changed course and helped Korea make a historic transition to green urban transport. It shifted from supply-side policies focused on expanding roadways and metro lines to green demand-side policies focused on creating transit-oriented cities. Today, Seoul boasts a passenger-trip share for metro and bus of more than 60 percent. Energy consumption in Korea’s road sector is lower than in other countries with similar gross domestic product (GDP). Congestion costs have been decreasing, and carbon dioxide (CO2) emissions in the transport sector have been kept under control. This path breaking transition was founded on multimodal solutions integrated by information and communication technology (ICT) in a context of strong political leadership and public financing.

Cairo Traffic Congestion Study : Final Report

World Bank
Fonte: Washington, DC Publicador: Washington, DC
Tipo: Economic & Sector Work :: Other Infrastructure Study; Economic & Sector Work
ENGLISH; EN_US
Relevância na Pesquisa
67.08%
The Greater Cairo Metropolitan Area (GCMA), with more than 19 million inhabitants, is host to more than one-fifth of Egypt's population. The GCMA is also an important contributor to the Egyptian economy in terms of GDP and jobs. The population of the GCMA is expected to further increase to 24 million by 2027, and correspondingly its importance to the economy will also increase. Traffic congestion is a serious problem in the GCMA with large and adverse effects on both the quality of life and the economy. In addition to the time wasted standing still in traffic, time that could be put to more productive uses, congestion results in unnecessary fuel consumption, causes additional wear and tear on vehicles, increases harmful emissions lowering air quality, increases the costs of transport for business, and makes the GCMA an unattractive location for businesses and industry. These adverse effects have very real and large monetary and nonmonetary costs not only for the economy of the GCMA, but given its size...

Cairo Traffic Congestion Study : Executive Note

World Bank
Fonte: Washington, DC Publicador: Washington, DC
Tipo: Economic & Sector Work :: Other Infrastructure Study; Economic & Sector Work
ENGLISH; EN_US
Relevância na Pesquisa
67.01%
The Greater Cairo Metropolitan Area (GCMA), with more than 19 million inhabitants, is host to more than one-fifth of Egypt's population. The GCMA is also an important contributor to the Egyptian economy in terms of GDP and jobs. The population of the GCMA is expected to further increase to 24 million by 2027, and correspondingly its importance to the economy will also increase. Traffic congestion is a serious problem in the GCMA with large and adverse effects on both the quality of life and the economy. In addition to the time wasted standing still in traffic, time that could be put to more productive uses, congestion results in unnecessary fuel consumption, causes additional wear and tear on vehicles, increases harmful emissions lowering air quality, increases the costs of transport for business, and makes the GCMA an unattractive location for businesses and industry. These adverse effects have very real and large monetary and nonmonetary costs not only for the economy of the GCMA, but given its size...

A Policy Framework for Green Transportation in Georgia : Achieving Reforms and Building Infrastructure for Sustainability

World Bank
Fonte: Washington, DC Publicador: Washington, DC
Tipo: Economic & Sector Work :: Policy Note; Economic & Sector Work
ENGLISH; EN_US
Relevância na Pesquisa
46.72%
The Government of Georgia is considering options for reducing fossil fuel imports in favor of introducing large scale use of domestic energy sources for public and private transportation. However, this must be considered within the overall context of green transportation-which will generate benefits well beyond the substitution of fossil fuels with domestic energy sources. The concept of green transportation has emerged in response to growing concerns about climate change; typically this refers to a transportation system characterized by low carbon emissions, i.e., Green House Gasses (GHG). In the context of Georgia, two other important development issues in green transportation in addition to GHG emissions are fossil fuel consumption and air pollution. For the purpose of this study, therefore, green transportation in Georgia refers to reducing the intensity of fossil fuel use and increasing reliance on indigenous energy sources (mainly hydropower), as well as minimizing adverse impacts on the global and local environment through reduced emissions of GHG and local pollutants. Greening transportation will create 'co-benefits': reducing fossil fuel use will help improve the balance of trade and energy security; and employing measures to avoid unnecessary trips and using fewer vehicles for the same number of trips (i.e....

Republic of Yemen : City and Inter-City Land Transport Sector - Strategy Note

World Bank
Fonte: World Bank Publicador: World Bank
Tipo: Economic & Sector Work :: Other Public Sector Study
ENGLISH
Relevância na Pesquisa
46.74%
The World Bank's study covered all modes of city and inter-city land transport, also designated in this report under the name of 'road transport'. However, the report focuses on the Governments two main concerns: the urban bus and taxi sector, which performs poorly and is a major cause of the growing traffic congestion in Yemeni cities, particularly in Sana'a; and the inter-city freight sector, which does not presently develop in ways that adequately serve the economy. Sana'a is indeed a large and fast growing city where public transport has become critical. Its population was 1.75 million in 2004, while forecasts are for 2.8 million for 2014 and 3.8 million for 2024. Yet, Sana'a's public transport system performs poorly. Similarly, the efficiency of inter-city freight transport is low and it does not promote trade, competition, and low price of basic commodities as it should. In addition, Yemen faces a very high rate of road accidents: in 2006, the number of recorded accidents was about 13,000, resulting in about 2...

Multimodal pricing and optimal design of urban public transport: The interplay between traffic congestion and bus crowding

Hensher, David A.; Rose, John M.; Tirachini Hernández, Alejandro Andrés
Fonte: Elsevier Publicador: Elsevier
Tipo: Artículo de revista
EN
Relevância na Pesquisa
46.73%
Artículo de publicación ISI; The interplay between congestion and crowding externalities in the design of urban bus systems is identified and analysed. A multimodal social welfare maximisation model with spatially disaggregated demand is developed, in which users choose between travelling by bus, car or walking in a transport corridor. Optimisation variables are bus fare, congestion toll, bus frequency, bus size, fare collection system, bus boarding policy and the number of seats inside buses. We find that optimal bus frequency results from a trade-off between the level of congestion inside buses, i.e., passengers’ crowding, and the level of congestion outside buses, i.e., the effect of frequency on slowing down both buses and cars in mixed-traffic roads. A numerical application shows that optimal frequency is quite sensitive to the assumptions on crowding costs, impact of buses on traffic congestion, and overall congestion level. If crowding matters to users, buses should have as many seats as possible, up to a minimum area that must be left free of seats. If for any other reason planners decide to have buses with fewer seats than optimal (e.g., to increase bus capacity), frequency should be increased to compensate for the discomfort imposed on public transport users. Finally...

Hybrid adaptive predictive control for a dynamic pickup and delivery problem including traffic congestion

Sáez Hueichapán, Doris Andrea; Núñez, Alfredo; Cortés, Cristián E.
Fonte: JOHN WILEY & SONS Publicador: JOHN WILEY & SONS
Tipo: Artículo de revista
EN
Relevância na Pesquisa
46.72%
This paper presents a hybrid adaptive predictive control approach to incorporate future information regarding unknown demand and expected traffic conditions, in the context of a dynamic pickup and delivery problem with fixed fleet size. As the routing problem is dynamic, several stochastic effects have to be considered within the analytical expression of the dispatcher assignment decision objective function. This paper is focused on two issues: one is the extra cost associated with potential rerouting arising from unknown requests in the future, and the other is the potential uncertainty in travel time coming from non-recurrent traffic congestion from unexpected incidents. These effects are incorporated explicitly in the objective function of the hybrid predictive controller. In fact, the proposed predictive control strategy is based on a multivariable model that includes both discrete/integer and continuous variables. The vehicle load and the sequence of stops correspond to the discrete/integer variable, adding the vehicle position as an indicator of the traffic congestion conditions. The strategy is analyzed under two scenarios. The first one considers a predictable congestion obtained using historical data (off-line method) requiring a predictive model of velocities distributed over zones. The second scenario that accepts unpredictable congestion events generates a more complex problem that is managed by using both fault detection and isolation and fuzzy fault-tolerant control approaches. Results validating these approaches are presented through a simulated numerical example.

Leaping Forward in Green Transport; The Case of Korea

Lee, Changgi; Vandycke, Nancy L.; Sung, Nak Moon; Choi, Sang Dae; Yi, Eun Joo Allison; Lee, Sangjoo
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Brief; Publications & Research :: Brief; Publications & Research
ENGLISH; EN_US
Relevância na Pesquisa
46.89%
What do Bangkok, Cairo, Lagos, Mumbai, and Nairobi have in common? These megacities, like others in burgeoning emerging market economies, are magnets for people seeking better opportunities. They also suffer from serious traffic congestion, high levels of greenhouse gas (GHG) emissions, and heavy air pollution. These urban areas face a stark dilemma: economic expansion attracts more people and vehicles; but the resulting traffic and pollution hinder further growth while reducing the quality of life for their citizens. In spite of rapid growth, urbanization, and motorization, Korea has succeeded so well in expanding the use of public transport that it has stabilized energy consumption per capita in the road sector. In 2010, Korea took aim at a new 10-year goal with its green transport master plan: reduce GHG emissions by one-third while maintaining its competitiveness. To do so, Korea seems poised to create more cutting-edge transport innovations that can serve as models for other countries.

Common Traffic Congestion Features studied in USA, UK, and Germany employing Kerner's Three-Phase Traffic Theory

Rehborn, H.; Klenov, S. L.; Palmer, J.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 23/12/2010
Relevância na Pesquisa
46.81%
Based on a study of real traffic data measured on American, UK and German freeways common features of traffic congestion relevant for many transportation engineering applications are revealed by the application of Kerner's three-phase traffic theory. General features of traffic congestion, i.e., features of traffic breakdown and of the further development of congested regions, are shown on freeways in the USA and UK beyond the previously known German examples. A general proof of the theory's statements and its parameters for international freeways is of high relevance for all applications related to traffic congestion. The application ASDA/FOTO based on Kerner's three-phase traffic theory demonstrates its capability to properly process raw traffic data in different countries and environments. For the testing of Kerner's "line J", representing the wide moving jam's downstream front, four different methods are studied and compared for each congested traffic situation occurring in the three countries.; Comment: 39 pages, 19 figures

A Kink Soliton Characterizing Traffic Congestion

Komatsu, Teruhisa S.; Sasa, Shin-ichi
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 26/06/1995
Relevância na Pesquisa
46.79%
We study traffic congestion by analyzing a one dimensional traffic flow model. Developing an asymptotic method to investigate the long time behavior near a critical point, we derive the modified Korteweg-de Vries (mKdV) equation as the lowest order model. There are an infinite number of kink solitons to the mKdV equation, while it has been found by numerical simulations that the kink pattern arising in traffic congestion is uniquely determined irrespective of initial conditions. In order to resolve this selection problem, we consider higher order corrections to the mKdV equation and find that there is a kink soliton which can deform continuously with the perturbation represented by the addition of these corrections. With numerical confirmation, we show that this continuously deformable kink soliton characterizes traffic congestion. We also discuss the relationship between traffic congestion and slugging phenomenon in granular flow.; Comment: 22 pages, REVTeX with 8 figures (uuencoded tar-compressed postscript)

Traffic congestion in interconnected complex networks

Tan, Fei; Wu, Jiajing; Xia, Yongxiang; Tse, Chi K.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
46.79%
Traffic congestion in isolated complex networks has been investigated extensively over the last decade. Coupled network models have recently been developed to facilitate further understanding of real complex systems. Analysis of traffic congestion in coupled complex networks, however, is still relatively unexplored. In this paper, we try to explore the effect of interconnections on traffic congestion in interconnected BA scale-free networks. We find that assortative coupling can alleviate traffic congestion more readily than disassortative and random coupling when the node processing capacity is allocated based on node usage probability. Furthermore, the optimal coupling probability can be found for assortative coupling. However, three types of coupling preferences achieve similar traffic performance if all nodes share the same processing capacity. We analyze interconnected Internet AS-level graphs of South Korea and Japan and obtain similar results. Some practical suggestions are presented to optimize such real-world interconnected networks accordingly.; Comment: 8 pages