Urban transportation and equity: A case study of Beijing and Karachi

Development of mega cities of Pakistan and China has greatly been affected by the growth in urbanization and motorization. The uncontrolled rise in urbanization, motorization, exclusionary planning and disproportionate investment in transportation infrastructure has created a socio-economic imbalance, thereby challenging the issue of equity. This paper focuses on a comparative social equity assessment of urban development, characteristics of supply and demand of transportation and infrastructure systems and the impact of existing strategies over equity in the development of urban and transportation system of Beijing and Karachi. The paper concludes by suggesting some strategies for the development of sustainable and equitable urban transportation systems.     

Emission rates of intermodal rail/road and road-only transportation in Europe: A comprehensive simulation study

Intermodal rail/road transportation combines advantages of both modes of transport and is often seen as an effective approach for reducing the environmental impact of freight transportation. This is because it is often expected that rail transportation emits less greenhouse gases than road transportation. However, the actual emissions of both modes of transport depend on various factors like vehicle type, traction type, fuel emission factors, payload utilization, slope profile or traffic conditions. Still, comprehensive experimental results for estimating emission rates from heavy and voluminous goods in large-scale transportation systems are hardly available so far. This study describes an intermodal rail/road network model that covers the majority of European countries. Using this network model, we estimate emission rates with a mesoscopic model within and between the considered countries by conducting a large-scale simulation of road-only transports and intermodal transports. We show that there are high variations of emission rates for both road-only transportation and intermodal rail/road transportation over the different transport relations in Europe. We found that intermodal routing is more eco-friendly than road-only routing for more than 90% of the simulated shipments. Again, this value varies strongly among country pairs.     

Assessing the quality of intercity road transportation of passengers: An exploratory study in Brazil

In Brazil, buses represent the main mode of public transportation. However, in recent years intercity and interstate bus companies have been facing a growing competition with other forms of transportation such as bus companies competitors, illegal transportation companies, chartered buses, and, more recently, air companies. In this scenario characterized by growing competition, it is essential to evaluate the quality of road transportation of passengers. In order to contribute to the analysis of this issue, this paper presents a methodological approach to assess the quality of intercity road transportation of passengers, according to the customers’ perspective. By conducting a case study in a city of almost 500,000 inhabitants from the interior of Rio de Janeiro, an Importance–Satisfaction Analysis (ISA) and an assignment procedure were used in order to obtain: (i) the main factors (criteria) that influence the quality of service intercity road transportation of passengers, (ii) the importance degree of criteria related to road transportation of passengers, (iii) the satisfaction of the users of road transportation under the considered criteria, (iv) the critical criteria/items, and (v) the categories which best represent the quality of service intercity road transportation according to the passengers’ perspective. Finally, several possible corrective actions to improve the quality of services considering each critical item/criterion were highlighted and special recommendations were done for the critical process (ticket sales).     

Toward regional transportation governance: a case study of Greater Vancouver

This paper discusses the evolving institutional structure and governance of transportation planning, policy development and transit delivery within one major North American city-region, the Greater Vancouver area. Various methods of transportation governance are explored from complete independence to full regional integration. The move away from a direct provincial role in transportation management to a greater regional transit authority is discussed and critiqued. This revised version was published online in June 2006 with corrections to the Cover Date.     

Transportation carbon dioxide emissions by built environment and family lifecycle: Case study of the Osaka metropolitan area

How a city grows and changes, along with where people choose to live likely affects travel behavior, and thus the amount of transportation CO₂ emissions that they produce. People generally go through different stages in their life, and different travel needs are associated with each. The impact of the built environment may vary depending on the lifecycle stage, and the years spent at each stage will differ. A family with children may last for twenty to thirty years, while the time spent without dependents might be short in comparison. Over a family’s lifecycle, how big of a difference might the built environment, through household location choice, have on the amount of transportation CO₂ emissions produced? From a climate change perspective, how significant is residential location on the CO₂ produced by transportation use? This paper uses data from the Osaka metropolitan area to compare the direct transportation CO₂ emissions produced over a family’s lifecycle across five different built environments to determine whether any are sustainable and which lifecycle stage has the greatest overall emissions. This understanding would enable the design of a targeted policy based on household lifecycle to reduce overall transportation CO₂ of individuals throughout one’s lifecycle. The yearly average per-capita family lifetime transportation CO₂ emissions were 0.25, 0.35, 0.58, 0.78, and 0.79 metric tonnes for the commercial, mixed-commercial, mixed-residential, autonomous, and rural areas respectively. The results show that only the commercial and mixed-commercial areas were considered to be sustainable from a climate change and transportation perspective.     

Evaluating gravel transport sustainability: A case study of Taiwan’s northeast corridor

We use social-eco-efficient analysis in the form of SEEbalance to evaluate gravel transport sustainability for trucking and two kinds of intermodal transportation. Results show that switching from trucks to intermodal transportation can improve the sustainability of gravel transportation in the northeast corridor of Taiwan. Sensitivity analysis shows that rail combined with truck intermodal transportation has competitive advantage despite the terminal’s location factor.     

交通运输服务标准体系构建策略和框架初探

本文在分析服务标准内涵的基础上,提出了交通运输服务标准界定的方法和标准体系框架构建的原则,并按照交通运输服务的重点领域,构建了交通运输服务标准体系的框架结构,提出了标准体系的实施的建议。     

Estimating historical hourly traffic volumes via machine learning and vehicle probe data: A Maryland case study

This paper focuses on the problem of estimating historical traffic volumes between sparsely-located traffic sensors, which transportation agencies need to accurately compute statewide performance measures. To this end, the paper examines applications of vehicle probe data, automatic traffic recorder counts, and neural network models to estimate hourly volumes in the Maryland highway network, and proposes a novel approach that combines neural networks with an existing profiling method. On average, the proposed approach yields 24% more accurate estimates than volume profiles, which are currently used by transportation agencies across the US to compute statewide performance measures. The paper also quantifies the value of using vehicle probe data in estimating hourly traffic volumes, which provides important managerial insights to transportation agencies interested in acquiring this type of data. For example, results show that volumes can be estimated with a mean absolute percent error of about 21% at locations where average number of observed probes is between 30 and 47 vehicles/h, which provides a useful guideline for assessing the value of probe vehicle data from different vendors.     

Mapping spatial accessibility of public transportation network in an urban area – A case study of Shanghai Hongqiao Transportation Hub

Accessibility is a key metric when assessing the efficiency of an urban public transportation network. This research develops a methodology for evaluating spatial accessibility of a system with multiple transportation modes in an urban area, Shanghai Hongqiao Transportation Hub (SHTH) and its surrounding area. The method measured total traveling time as an accessibility indicator, which summed the time people spent on walking, waiting, transfer and transportation in a journey from the SHTH to destinations. Spatial accessibility was classified into five levels from very high to very low. The evaluation was conducted at a cell-by-cell basis under an overall scenario and three specific scenarios. Evaluation results were presented in a series of maps. The overall accessibility scenario shows a concentric-ring trend decreasing from the SHTH to the fringe of the study area. Areas along the metro lines generally have a much higher accessibility than those along the bus lines with some exceptions where bus routes play a more important role. Metro stations identified as either time-saving or time-consuming points are mainly distributed around the urban center. Some suggestions are proposed for improving accessibility of public transportation network in the study area. The results from this study provide a scientific basis and useful information for supporting decision-making on urban planning, and assisting dwellers to travel in a time-efficient manner. The methodology offers a simple, flexible way to the spatial evaluation, metro station identification and network modification of accessibility of public transportation systems with multiple transportation modes.     

Use characteristics and demographics of rural transit riders: a case study in Tennessee

Intercity bus (ICB), deviated fixed route transit (DFRT) and demand responsive transit (DRT) are three major modes of rural public transportation. This paper focuses on the characteristics and motivations of DFRT and DRT riders, compared to non-riders, in Tennessee. A rural DFRT rider survey, a rural DRT rider survey and a rural (non-rider) resident survey were performed. It is found that DFRT and DRT riders have similar demographics to ICB riders. The most common trip purpose for DFRT and DRT passengers is medical care, which is different from ICB trips. Ninety percent of the riders have difficulty finding alternative transportation modes, suggesting they are captive riders, not choice riders. Regression results indicate that people choosing transit modes tend to have lower personal and household income, own fewer cars, to not be homeowners, and be of non-white race. Rural residents who receive more education are more likely to be open-minded to use rural transit.     

A system dynamics modeling for urban air pollution: A case study of Tehran,Iran

Development of strategies to control urban air pollution is a complex process involving a wide range of sciences. In this study a system dynamics model is proposed in order to estimate the behavior of parameters affecting air pollution in Tehran. The proposed model includes two subsystems: (1) urban transportation, (2) air polluting industries. In this paper, several policies are proposed to mitigate air pollution. The proposed model is simulated under several scenarios using historical data of transportation and industrial sectors in Tehran. Policies are categorized as: (1) road construction, (2) technology improvement in fuel and automotive industries, (3) traffic control plans, (4) development of public transportation infrastructures. The results show effectiveness of the proposed policies. In this case, technology improvement in fuel and automotive industries and development of public transportation infrastructures are more effective policies in order to reduce air pollution.     

The relative contribution of transportation to supply chain greenhouse gas emissions: A case study of American wheat

This life cycle assessment case study puts the supply chain contribution of transportation to greenhouse gas emissions in context with other contributors using American wheat grain as a representative product. Multiple locations, species and routes to market are investigated. Transportation contributes 39–56% of the supply chain emissions, whereas there is a 101% intra-species and 62% inter-species variation in greenhouse gas emissions from production, demonstrating that transportation is both of smaller magnitude, and less sensitive than other factors, in particular, field sequestration.     

Feasibility study of aerial ropeway transit in the Holy City of Makkah

The planning and implementation of a multimodal transportation system in the Holy City of Makkah to handle the huge volumes of pilgrims to the City is not a straightforward mission, as Makkah poses numerous challenges including its unique seasonal demand patterns, mountainous terrain, and limited space. Aerial ropeway transit (ART), a promising transport technology solution, could be an important component of this system. This paper presents the results of a technical and economic feasibility study to explore the potential of introducing ART service in Makkah. The study reveals that, overall, ART service on some corridors in Makkah is technically feasible, and with some necessary enforcement measures to attract ridership could become a profitable transportation investment. Specifically, the study recommends using ART for special user groups and service/emergency crews during peak seasons and opening ART to the public as a premium service during the off-peak season.     

交通运输能耗与排放统计监测平台及应用研究

在我国交通运输行业节能减排的背景下,本文以交通运输行业能耗特点与统计监测方法为基础,建立涵盖了公路客运、公路货运、城市公交、城市出租、水路运输、港口生产等行业的能耗碳排统计监测系统,分析了省级交通运输能耗与排放特点,明确了能耗数据统计对象与内容,并对能耗数据采集的方法进行了研究,建立了省级交通运输能耗统计监测系统,并以辽宁省交通运输为依托,对全省交通运输行业能耗统计监测系统进行了验证与应用,同时也为交通运输行业的节能减排提供了决策支撑和数据支持。     

Transportation mode choice and city-suburban public transportation service

A model is presented to describe the dynamics of transportation mode choice in which the interaction between transportation users and a public transportation authority results in self-organization. The model illustrates that a sufficient number of connections between a central city and its suburbs are required for self-organization to occur whereby public transportation use and service will grow.     

城市绿色交通发展历程及趋势分析

绿色交通理论是基于可持续发展理念而提出的交通领域的全新理念。本文在总结绿色交通发展历程的基础上,系统整理绿色交通理论体系的内涵。借鉴国内外绿色交通既有发展实践,提出我国绿色交通体系未来的发展方向。     

Performance comparison between pedestrian push-button and pre-timed pedestrian crossings at midblock: a Korean case study

Walking has been highlighted as an independent transportation mode as well as an access/egress mode to/from public transit to encourage the use of more sustainable transport systems. However, walking does not seem to have priority over other transportation modes, especially in areas where various modes of movement are in conflict. The pedestrian push-button system seems to be a solution to distribute the right of way. The focus of this study is on the performance issue of the pedestrian push-button. Specifically, this study deals with issues related to mid-block crossings and attempts to answer two questions: whose waiting time is longer at pre-timed and push-button crossings, pedestrians, or vehicles? and which system – pre-timed or push-button – is better in terms of total waiting time? According to our simulation analyses, if the pedestrian flow rate is less than 120, 85, and 70 ped/h for two-, three-, and four-lane roads, respectively, the push-button system is recommended.     

An empirical study of simulation-based dynamic traffic assignment procedures

Abstract

Under Intelligent Transportation Systems (ITS), real-time operations of traffic management measures depend on long-term planning results, such as the origin–destination (OD) trip distribution; however, results from current planning procedures are unable to provide fundamental data for dynamic analysis. In order to capture dynamic traffic characteristics, transportation planning models should play an important role to integrate basic data with real-time traffic management and control. In this paper, a heuristic algorithm is proposed to establish the linkage between daily OD trips and dynamic traffic assignment (DTA) procedures; thus results from transportation planning projects, in terms of daily OD trips, can be extended to estimate time-dependent OD trips. Field data from Taiwan are collected and applied in the calibration and validation processes. Dynamic Network Assignment-Simulation Model for Advanced Road Telematics (DYNASMART-P), a simulation-based DTA model, is applied to generate time-dependent flows. The results from the validation process show high agreement between actual flows from vehicle detectors (VDs) and simulated flows from DYNAMSART-P.     

Transportation and energy—A future confrontation

An examination of the relationship between energy supplies and transportation systems indicates that a major confrontation is forthcoming. Predictions of the world's petroleum supplies and the primary dependence of transportation systems on petroleum show that there will be a depletion of these supplies in the next 50 years unless major changes in transportation and energy planning and policy making are forthcoming. A closer examination of specific transportation systems through the use of the transportation/ energy efficiency indicates that automobiles, aircraft and intercity trucking are most inefficient on a mobility per unit of petroleum basis. Recommendations on the difficult problem of how to account for the depletion characteristics of transportation systems are given. These include coordinated transportation and energy planning, restricted petroleum and transportation toll and tax rates, research and development on propulsion systems less dependent on petroleum, and a shifting of emphasis to higher transportation/energy efficiency systems such as compact automobiles, buses and trains.