1,721,149 research outputs found
Introduction to the Handbook of Public Transport Research
Full text linkThis Handbook of Public Transport Research aims to provide a comprehensive overview of the latest research in a growing field: the field of research on urban public transport. The quantity of public transport related research papers has doubled in the last nine years. Why? For two reasons. First, researchers have been increasingly inspired by the topic. It is an applied and practical topic affecting the quality of life of billions of people. It is also a field with significant challenges, seeking new and original solutions. These challenges range from the difficult interface of engineering, operations and human perceptions in user satisfaction and performance management, to the tricky balance between prudent financial management, operations planning and the social access goals making subsidies essential. These challenges require a multi-disciplinary perspective to wicked problems in Engineering, Planning, Psychology and Design, which is why the field is intellectually as well as tactically challenging. The foundation of many of these challenges is the conflicting congestion and environmental relief, and the social equity objectives that justify public transport in cities.</p
The two-wheeled renaissance in China-an empirical review of bicycle, E-bike, and motorbike development
No full textThis paper is an empirical review of the development of two-wheeled transport, comprising human-powered bicycles, E-bikes, and motorbikes in China from 1985 to 2019, aimed at investigating the development of two-wheeled transport in China. A series of demand-side factors (e.g., rapid urbanization) and supply-side factors (e.g., obsolete infrastructure) are explored. The mode share of human-powered bicycles decreased steadily until 2016, the year dockless bikeshare (DBS) emerged. During that time, government policy changed from "encouraged", "discouraged", "converted and re-recognized" to "encouraged again" due to sophisticated socio-economic change. E-bikes and motorbikes witnessed an independent growth trend and changing political attitude from that of human-powered bicycles. The future of the human-powered bicycle transport mode in China is promising, due to favorable government policies and the growing demand from users for a flexible mode of transport to serve short-middle distance and last-mile trips. E-bikes have an uncertain future since local policies differ, and safety issues are yet to be addressed. Motorbikes, due to their negative safety and environmental considerations, have been increasingly replaced by automobiles, and this makes their future position marginal.
To be or not to be dockless: Empirical analysis of dockless bikeshare development in China
No full textThis paper discusses the development of shared bike programs in China, especially the innovative dockless bikeshare (DBS) system, using up-to-date empirical analysis. Bicycle sharing programs had existed in China since 2008 but overall bicycle mode share decreased until 2016 when DBS emerged. A comparison of classical city docked bikeshare (BS) programs found that government oriented operators and a low financial threshold for users were the keys to the success of docked BS in China. In less than two years, a new, innovative, flexible, shared bicycling system the DBS has grown from nothing to a substantial 23 million fleets, covering over 200 cities and regions, making docked BS appear insignificant. It is a highly capital-driven, privately-operated business model, largely deployed in cities in conjunction with urban railway systems and has achieved high penetration in mega cites (e.g., 0.135 fleet/resident in Beijing). The development of DBS has experienced "free growth", "regulated" and "limited" phases in a short time. While the central government initially held a "neutral-positive" policy towards this new system, the rapid expansion of dockless fleets soon exceeded cities' limits and resulted in local government policies changing from "neutral-positive" to "neutral-negative", and from August 2017, forceful limiting regulations have been implemented. DBS systems have advantages such as easy access using a smart phone, convenience of pickup and park and low cost. These merits attract its main users, who are found to be young, highly educated with almost equal numbers of males and females. DBS trips are mainly short, with high frequency and used for commuting purposes. DBS systems have burgeoned due to three factors: (1) those promoting user demands, (2) those winning partial support of government, and (3) those promoting operators' supply. The results show that rapid growth of dockless bikeshare programs is mainly "supply-driven by operators" rather than by "user demand" or "triggered by government policy". Financial sustainability, vandalism and threat to bicycle industry by DBS are the three main challenges that require investigation, especially, the fact that the booming DBS market may cause low profitability for local bicycle manufacturers and thus make the entire industry fragile. Feasibility of docked bikeshare and dockless bikeshare are compared and concluded in the end.
Measuring immediate impacts of a new mass transit system on an existing bike-share system in China
No full textMass transit systems as metros thrive nowadays in China – the largest bike-share market all over the world. Hence, it is meaningful to study how a new metro system impact on an existing bike-share system (BS) and understand how they interact to ensure they inter-enhance rather than inter-replace each other. By using trip-pattern and land use to create control and treatment groups based on trip data from Suzhou Public Bicycle System (SPBS), a ‘‘before-and-after’’ study is initiated to measure changes of an existing BS during a period when a new metro system (Here, Metro line 4: M4) opened. Normalized bike flow data (NF) is introduced to cluster and indicate trip-pattern in this study. The result indicates that most SPBS ridership and users within the metro’s catchment (the treatment group) have largely increased since the introduction of the M4, while non-commuting cycling increased more than commuting cycling. The exception happens in metros’ hub, where SPBS ridership slightly decreased after M4. As for SPBS trip-pattern, before M4 was introduced, trip-pattern in CBD areas in Gusu District is found to be partially imbalanced (high returning in the morning and high renting in the evening), while balanced pattern (similar returning and renting in morning and evening) is more often seen in other areas. After M4 was introduced, a general trip-pattern change from the balanced to the imbalanced is observed regardless of land use, except for educational land use existing in Wuzhong District. This further indicates that after new metros was introduced, SPBS tends to serve “first-mile” interchange (origins to metros) rather than “last-mile” interchange (metros to destinations) in the morning and vice versa in the evening regardless of land use type. This unique pattern could lead to different policy and management in enhancing interchanging service between BS and mass transit
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Modelling the net traffic congestion impact of bus operations in Melbourne
No full textBus services can be seen as a way to reduce traffic congestion where they can encourage a mode shift from car. However, they can also generate negative effects on traffic flow due to stop-start operations at bus stops. This paper aims to assess the net impact of bus operations on traffic congestion in Melbourne. The methodology used to achieve this aim comprised of three main stages. First, a primary survey was conducted to determine the mode shift from bus to car when buses are unavailable. This figure was used to estimate the positive impact of buses on relieving congestion. Second, the negative impact of buses was investigated by considering the effect of bus stop operations on vehicle traffic flow using microsimulation. Finally, the net effect was estimated by contrasting congestion measures determined from a traditional four step model between two scenarios: ‘with bus’ and ‘without bus’. The results indicated that Melbourne’s bus network contributes to reduce the number of severely congested road links by approximately 10% and total delay on the road network by around 3%. The highest congestion relief impact was found in inner Melbourne with a 7% decrease in vehicle time travelled and total delay, and 16% decrease in the number of heavily congested road links. In inner areas, the level of congestion is relatively high so the mode shift from car to bus, even if not as high as middle and outer areas, have a significant effect on relieving traffic congestion. Areas for future research are suggested such as investigating the long-term effect of buses on traffic congestion
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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