Understanding the contextual factors associated with why adults walk is important for those interested in increasing walking as a mode of transportation and leisure. This paper investigates the relationships between neighborhood-level sociodemographic context, individual level sociodemographic characteristics and walking for leisure and transport. Data from two community-based studies of adults (n=550) were used to determine the association between the area-sociodemographic environment (ASDE), calculated from U.S. Census variables, and individual-level SES as potential correlates of walking behavior. Descriptive statistics, mean comparisons and Pearson's correlations coefficients were used to assess bivariate relationships. Generalized estimating equations were used to model the relationship between ASDE, as quartiles, and walking behavior. Adjusted models suggest adults engage in more minutes of walking for transportation and less walking for leisure in the most disadvantaged compared to the least disadvantaged neighborhoods but adding individual level demographics and SES eliminated the significant results. However, when models were stratified for free or reduced cost lunch, of those with children who qualified for free or reduced lunch, those who lived in the wealthiest neighborhoods engaged in 10.7 minutes less of total walking per day compared to those living in the most challenged neighborhoods (p<0.001). Strategies to increase walking for transportation or leisure need to take account of individual level socioeconomic factors in addition to area-level measures.
The world of highway building has seen a revolution in the last two decades, as the regulatory environment has experienced a major metamorphosis. The Glenn M. Anderson Freeway- Transitway (1-105), a so-called "sensitive" freeway, escaped being a casualty of the freeway revolt. Novel features of the I-105 are a result of a consent decree that established special institutions and procedures that govern virtually all aspects of the freeway's design and construction. Using an augmented case study approach, we assess how the freeway differs from the project that might have evolved had parties to litigation not been able to resolve their differences. We assess how agencies, groups and individuals view the costs and benefits of the consent decree. We find consistent differences in impact perceptions between transportation agency and local city affiliates. The results shed light on the motivations of local citizens who oppose what outside observers might regard as regionally attractive transportation facilities. Rather than a rigid not-in-my-backyard (NIMBY) response, opposition reflects a qualitatively different calculus for weighing environmental and social impact data.
Structural changes over time in commuters’ travel patterns are examined by formulating and estimating simultaneous equations model systems of activity engagement and travel. Results of large-scale household travel surveys conducted in the Osaka metropolitan area of Japan in 1980, 1990 and 2000 are used with matching demographic, land use, and network data. Statistical examinations of the model systems indicate that the structural relationships underlying travel behavior have not been stable over the 20 years. Overall, expanding tendencies in out-of-home activity engagement and travel are exhibited by both auto and transit commuters, but in different ways. The study results challenge the conventional wisdom that auto travelers tend to chain trips; transit commuters make more stops and chain trips more often than do auto commuters in the Osaka area, suggesting that travel patterns are heavily influenced by transportation networks and land use developments.
This study aims to investigate how seaport research has been conducted from the methodological perspective. To this end, this study reviews published port literature for the last three decades (1980-2000s). The investigation primarily categorises the literature according to various methodological issues such as research paradigm, research strategy, base-disciplines, research methods and analysis techniques in order to provide meaningful implications on methodological evolution in seaport research for the period. This study suggests methodological bias in port research to a positivistic paradigm, following a quantitative trajectory moving from conceptual to empirical studies. In addition, the increased use of mathematical modelling and advanced statistical analysis methods is clearly observed. The introduction of advanced analytical tools used in other academic disciplines facilitates discussions in particular research area and amplifies the literature in those areas. This paper also suggests research gaps from the methodological perspective and implications for future port research.
The changing modal composition and volume of worktravel in London, Birmingham and Manchester and their resultant energy consumption implications are analysed in this research. The data are derived from the 1981 and 1991 Population Censuses special workplace statistics for small areas (wards). The results point to increases in total worktravel energy consumption due to both a rise in the volume of travel and the changing composition of travel in favour of less energy efficient car-based modes and away from more energy efficient public transport modes. Average energy intensities per person trip are generally shown to be increasing, and, from an energy conservation perspective, the trends are unhelpful. Policy measures designed to influence these trends are being devised and deployed but their effect remains to be seen.
Performance in single mode bus transit systems is analyzed in this paper. The paper points to two potential problems in using partial productivity and other measures in assessing the performance levels of transit systems. One solution suggested is total factor productivity which is shown to be mathematically related to many of the traditional measures of performance. Next, total factor productivity is determined using data for a sample of single mode bus transit systems. As part of the analysis, a neoclassical cost function is developed which allows for decomposition of total factor productivity among technical change and economies of scale. The major conclusions include growth of total factor productivity of 1.1% per year and technical growth of 1.14% per year. Growth of total factor productivity is attributed to output, the productivities of all inputs and technical change. Policy implications of these findings are examined.
In the matter of port legislation, the nineties was a period of maximum interest in Spain. Two laws enacted in 1992 and 1997, respectively, aimed at increasing the autonomy of individual ports in the management and organization of its activities. Before 1992 two different models of management coexisted in the Spanish port system: autonomous decision-making ports and ports controlled in its decision-making by the Central Government. The question we address in this paper is how these legislative changes have affected the evolution of the levels of traffic of the Spanish port system from 1992, date of introduction of the first law, to 2003, date of approval of a third legislative change that remains out of this analysis for lack of sufficient data. We find an important impact of legislative changes on port traffic by way of an estimated econometric model over the 1966–2003 period. We control for the effect of other variables that might have influenced Spanish maritime traffic such as international maritime flows, taken as a proxy of globalization, or gross domestic product, under the hypothesis that maritime transport is a demand derived of economic activity. We provide evidence supporting that greater port autonomy had beneficial effects for the Spanish port system as a whole.
Recent earthquake disasters have caused major damage to transportation networks, leading to significant economic disruption. While this suggests the need to evaluate total system performance in transportation risk assessment, in addition to examining the vulnerability of individual components such as bridges, no appropriate measures currently exist. This paper develops post-disaster system performance measures and applies them to the urban rail and highway transportation systems in the Kobe, Japan, region devastated by the 1995 Hyogoken-Nanbu earthquake. Performance is evaluated in terms of network coverage and transport accessibility. Performance degradation was much more severe for highways and railways than for other lifeline infrastructure systems. Both transportation systems fared poorly in the disaster but service restoration proceeded much more rapidly for rail. The restoration of highway system performance correlated closely with the recovery of highway traffic volumes. The paper further develops a measure of subarea transport accessibility and applies this to Kobe's constituent city wards. Results indicate substantial spatial disparity that is maintained throughout the restoration period. Comparisons with the 1989 Loma Prieta and 1994 Northridge earthquakes in the US show that although these disasters caused notable damage to highway bridges, system performance degradation was small in comparison with the Kobe experience. The paper argues that explicitly measuring transportation system performance can greatly facilitate both understanding the effects of historic disasters and preparing for future hazard events.
Using data envelopment analysis and the Malmquist productivity index, this paper examines changes in the productivity of the major United States passenger airlines from 2000 to 2004. The analysis finds that there was a significant improvement in the productivity of the carriers at transforming labor, fuel and passenger seating capacity into available seat-miles during this period. Most of the productivity improvements came about from the efficiency laggards catching up with the efficiency leaders in the industry. To a lesser extent, the adoption of new technologies improved productivity over this period.
This paper describes important aspects of the design of the Athletes transportation system for the Athens 2004 Olympic Games. The unique characteristics of this network include the close dependence of the vehicle schedules on the competition and training program, the requirement for 100% service reliability, as well as the requirement for full system monitoring and control. In this paper we present methods for the development of service specifications, estimation of the bus fleet size, the design of the network's organization and management system, and corresponding critical implementation issues. All these issues are relevant to the design and management of bus transport systems for large events.
Road transport is a major source of air pollutant emissions in European cities. Moreover, vehicle exhaust emissions have been the cause of much concern about the effects of urban air pollution on human health. Local authorities need to develop strategies to control vehicular emissions through technological and socioeconomical measures. For this reason, an efficiency assessment of possible future measures to reduce air pollution is required for future traffic planning, regulatory and fiscal initiatives. This paper presents the assessment of several mobility and technology scenarios that can be used for emission reductions in Madrid (Spain) in the period 2004–2012. Pollutants considered are those related to typical air quality problems in urban areas in Europe (SO2, NOx, NMVOC, heavy metals, CO and particulate matter) and CO2 as a greenhouse gas.Results show an expected increase in mobility but a decreasing trend in future traffic-related emissions, except for CO2. This reduction is due to technological improvements linked to European Legislation for road vehicles (Euro Standards). CO2 emissions are expected to increase because the technological improvements will not be able to counteract the effect of the large mobility increase. With regard to control strategies, the most effective measure for emission reductions is fleet renewal. According to the hypotheses made in the paper, this would reduce, on average, the pollutant emission by 16.04%. With regard to CO2 emissions, the use of biofuels and the decrease in mobility are the most effective measures.
The Stockholm congestion charging trial in 2006 demonstrated the effects of a full-scale time-differentiated urban road toll scheme. Improvements in travel times were large enough to be perceived by the general public. This was pivotal to the radical change of public attitudes that occurred during the trial and that resulted in a positive outcome of a subsequent referendum on a proposal for making the system permanent. This paper summarises the effects of the trial and analyses to what extent targets were met. Effects on congestion reduction were larger than anticipated, which also resulted in favourable economic and environmental effects. The trial showed that a single-cordon toll could affect traffic within a large area, i.e., not just close to the zone limits.
The interrelatedness of transportation development and economic growth has been a constant theme of geographic inquiries, particularly in economic and transportation geography. This paper analyzes the expansion of China's railway network, the evolution of its spatial accessibility, and the impacts on economic growth and urban systems over a time span of about one century (1906-2000). First, major historical events and policies and their effects on railway development in China are reviewed and grouped into four major eras: preliminary construction, network skeleton, corridor building, and deep intensification. All four eras followed a path of "inland expansion." Second, spatial distribution of accessibility and its evolution are analyzed. The spatial structure of China's railway network is characterized by "concentric rings" with its major axis in North China and the most accessible city gradually migrating from Tianjin to Zhengzhou. Finally, the study indicates that railway network expansion has significantly improved economic development and heavily influenced the formation of urban systems in China.
The US faces a number of important issues in the way it organizes and manages transportation facilities and services. A key issue is how to create organizations that pay attention to customers and focus on results and performance. However, these two organizational characteristics are often difficult to achieve in formal organizations like governments, which are bound by requirements for procedural integrity. This paper examines a way out of this dilemma: transportation organizations can participate in voluntary consortia, which may offer more flexibility and adaptability and facilitate organizational learning. To gain new insights into the potential benefits of voluntary consortia this paper examines two case studies of transportation-related voluntary consortia, taking an organizational learning perspective. It concludes that although further research is needed, consortia may offer many benefits, including their ability to provide a quick, low-threat response to changing conditions.