Measuring Space-Time Accessibility Benefits within Transportation Networks: Basic Theory and Computational Procedures

Accessibility is a fundamental but often neglected concept in transportation analysis and planning. Three complementary views of accessibility have evolved in the literature. The first is the constraints-oriented approach, best implemented by Hägerstrand's space-time prisms. The second perspective follows a spatial interaction framework and derives “attraction-accessibility measures” that compare destinations' attractiveness with the travel costs required. A third approach measures the benefit provided to individuals by the transportation/land-use system. This paper reconciles the three complementary approaches by deriving space-time accessibility and benefit measures that are consistent with the rigorous Weibull axiomatic framework for accessibility measures. This research also develops computational procedures for calculating these measures within network structures. This provides realistic accessibility measures that reflect the locations, distances, and travel velocities allowed by an urban transportation network. Since their computational burdens are reasonable, they can be applied at the urban scale using a GIS.     

Measuring Space-Time Accessibility Benefits within Transportation Networks: Basic Theory and Computational Procedures

Accessibility is a fundamental but often neglected concept in transportation analysis and planning. Three complementary views of accessibility have evolved in the literature. The first is the constraints-oriented approach, best implemented by Hägerstrand's space-time prisms. The second perspective follows a spatial interaction framework and derives “attraction-accessibility measures” that compare destinations' attractiveness with the travel costs required. A third approach measures the benefit provided to individuals by the transportation/land-use system. This paper reconciles the three complementary approaches by deriving space-time accessibility and benefit measures that are consistent with the rigorous Weibull axiomatic framework for accessibility measures. This research also develops computational procedures for calculating these measures within network structures. This provides realistic accessibility measures that reflect the locations, distances, and travel velocities allowed by an urban transportation network. Since their computational burdens are reasonable, they can be applied at the urban scale using a GIS.     

基于多维目标的城市宜居交通概念、要素与框架

宜居性一直是人类的共同理想和追求,人本导向下的宜居城市建设是新型城镇化建设的重要内容。城市交通是城市形态和出行行为的主要载体,实现交通与城市的和谐发展是宜居城市建设的根本和关键要素。本研究在梳理国内外相关研究的基础上,主要从理论层面探讨了基于多维视角的城市宜居交通概念、目标、要素与框架。本文强调了宜居交通的多维目标,认为宜居交通建设应更全面地与经济、社会和环境目标相融合,满足更广泛的需求和相关规划体系的有效性。同时,提出宜居交通构建的主要策略和研究的主要方向。     

基于综合可达性的北京城市增长模拟与管控模式优化

社会经济活动的空间重构与交通设施配置息息相关,可达性成为优化城市空间结构,调控城市空间开发的重要手段。在以矢栅一体化的综合可达性测度并构建城市增长模型的基础上,对北京城市增长进行了成功模拟,透视了基于综合可达性导向发展模式的基本特征与主要问题,并提出了基于综合可达性的城市增长调控模式优化方案。研究发现：①城市增长密集发生在建成区周围可达性优越的区域,随着与城市中心的距离增加,城市增长的概率降低,反映了北京单中心的城市发展模式;②受城市规划与交通设施规划失调影响,可达性提升程度越大的区域并不一定带来更高的城市增长开发概率,严重削弱了可达性对城市增长的引导作用;③基于综合可达性的城市增长调控模式的优化方案,要以交通设施规划为基础,并合理耦合空间规划,才能更为有效地引导城市空间良性增长并预防规划失效。基于综合可达性的城市增长模型建立与调控模式优化方案的提出,对于确立与提升交通引导城市增长的基础性地位,优化城市空间结构具有重要的理论和现实意义。     

A Gravity Model with Variable Coefficients: The EEC Trade with Third Countries

Gravity models with fixed coefficients have been used to explain the trade flows between countries different in income levels and separated by long distances. It is unrealistic to assume that these models can hold with the same parameters across very heterogeneous countries. This paper proposes and estimates an international trade model with variable coefficients constructed by combining Pöy-hönen's and Linnemann's gravity-based trade models via the expansion method.     

SEARCH FRICTIONS,UNEMPLOYMENT, AND HOUSING IN CITIES: THEORY AND POLICIES

We propose an urban search‐matching model with land development. Wages, unemployment, prices of housing and land are endogenously determined. We characterize the steady‐state equilibrium and then discuss the issue of efficiency. To explore interactions among markets, we implement comparative static analysis. We also consider three policies: an entry‐cost policy that reduces firms' entry, a transportation policy that reduces commuting costs, and a housing policy that decreases rental prices. We find that the transportation and housing policies are more efficient if the unemployment rate is low, while the entry‐cost policy is more efficient if the unemployment rate is high.     

Land suitability assessment for locating industrial parks: a hybrid multi criteria decision‐making approach using Geographical Information System

Industrial areas play a critical role in urban and regional planning, especially for developing countries where reliable strategies for these areas can promote economic and environmental efficiency. The present study provides an integration of hybrid multi‐criteria decision‐making (MCDM) theories and Geographical Information System (GIS) processes in order to assess the suitability of an industrial location. Unlike traditional models, an efficient decision analysis demands handling uncertainties and considering dependencies between criteria. The proposed MCDM framework uses fuzzy theory because of the vagueness of experts' judgements. Moreover, Decision‐Making Trial and Evaluation Laboratory (DEMATEL) is employed to investigate interrelationships among the criteria. In the proposed empirical solution, analytic network process (ANP) principles are used to deal with systematic interactions. We considered several factors such as accessibility, topography, proximity, and socioeconomic characteristics in the decision‐making procedure for a sustainable industrial park. The system is applied to Hamadan province, Iran to determine appropriate locations that are the results of the aggregation of criteria maps in a GIS environment. The results demonstrate that accessibility and economic indicators are essential for choosing an industrial park's location. Additionally, the proposed method can be applied for an efficiency evaluation of available industrial parks.     

Identifying metro station types based on transfer purposes: An application of bike-sharing data in Xiamen,China

With the networking of urban rail transit and the large-scale development of bike-sharing, metro and bike-sharing connection has become the preferred way of daily travel for residents of Xiamen. Current studies mainly identify metro station types based on node and place orientation, lacking behaviour-based investigation. To fill this gap, this study aims to explore the classification of metro stations based on transfer purposes by combining bike-sharing and point of interest data in Xiamen, using buffer analysis, kernel density estimation, and DBSCAN clustering algorithm comprehensively. The results indicate the following. (1) Distinct transfer purposes have significant agglomeration characteristics and present poly-centric spatial pattern, an authentic portrayal of Xiamen's land use function. (2) The heterogeneity of connection flow between different transfer purposes and metro stations is apparent. The distribution of flow and flow direction within the same transfer purpose is also in non-equilibrium. (3) Based on traffic connection analysis, metro stations are divided into seven types: transportation hub, employment-oriented, residence-oriented, job-housing balance, school-oriented, traffic-tourism integration, and business connection types. The obtained results assist in improving the transportation connection environment, perfecting urban land use planning, and enhancing low-carbon and green travel.     

Smart growth strategies,transportation and urban sprawl: simulated futures for Hamilton,Ontario

North American cities have undergone dramatic changes over the last century. Locations that were once inconvenient have become accessible through extensive road networks leading to population decentralization from the traditional urban centre to suburbia, creating polycentric sprawls from once monocentric communities. Hamilton, Ontario is one such city. The decentralization and urban decline of the city is widely attributed to sprawling development. This change in the sociospatial structure creates challenges for transportation planners as we see greater automobile dependency, greater commuting distances and increased congestion. Smart growth policies such as urban residential intensification (URI) aim to increase population densities in the urban core. This exploratory study estimates the benefits of such policies from a transportation aspect. It is predicted that the City of Hamilton will experience household growth of approximately 80,000 households over the period 2005–2031. Using IMULATE, an integrated urban transportation and land‐use model, a variety of development scenarios model this anticipated growth. Changes in vehicular emissions, traffic congestion and energy consumption as a result of URI are examined. Models of the land‐use/transportation relationship demonstrate how increasing population densities within a city's urban centre drastically reduce congestion, emissions and gasoline consumption.     

The contribution of Sir Alan Wilson to spatial interaction and transport modelling

ABSTRACT

In a series of papers in the mid-1960s and early 70s, building on his key 1967 paper, Alan Wilson made a series of fundamental contributions to the specification and application of land-use transport models. In this paper the basis of his entropy-maximizing approach to spatial distribution models is outlined with a demonstration that the methods have applications very much beyond its transport roots. The entropy maximization method laid the foundations for the development of a range of multinomial logit share models. He expanded the core transport ideas to the whole range of comprehensive models, initially building on, and extending, Lowry's iconic Pittsburgh model. The factors that have sustained the longevity of Wilson's models are explored and articulated.     

Prospects of Development of the Industrial Complex of the Volga-Vyatka Major Economic Region

The Volga-Vyatka region, one of the Soviet Union's leading machinery and chemical producers, has potentialities for further growth in these two industries. Favorable factors are a skilled labor force and a central transportation location in European Russia, midway between raw-material suppliers and markets. In view of industrial overcrowding in the Gor'kiy and, ultimately, Kirov urban areas, future industrial construction should be planned in medium-size and small cities and in the region's peripheral areas.     

Urban Transition and Interstate Relations in a Dynamic Post-Soviet Borderland: The Xinjiang Uygur Autonomous Region of China

Two noted American geographers examine transition in the Xinjiang Uygur Autonomous Region (a de facto Soviet protectorate in the 1930s and early 1940s) within the context of that region's strategic position. The paper, based on field work exploring urbanization in the People's Republic of China, investigates the area's role as a bridgehead and corridor for emerging economic relations between China and the neighboring republics of Central Asia. The focus is on the demographic dimensions of urban growth and the underlying geopolitical and economic factors. Considerable attention also is given to the implications of increased trade and improvements in transportation links with the newly independent Central Asian states. Journal of Economic Literature, Classification Numbers: F14, F15, O15, O18. 4 figures, 6 tables, 51 references.     

An empirical study on the modification of China's current urban social security system

This study challenges the conventional correlation between economic performance and the level of the development of social security systems. By focusing on China's urban areas, we provide an overview of the components and benefits, from a comparative perspective, of China's current social security system. We also create a comprehensive and generally applicable method using factors such as economics and population, among others, as standards to evaluate the efficacy of China's system. In order to demonstrate our primary hypothesis – that the Chinese Communist Party government has to modify its social security system to adapt to or bring about changes in the basis of its legitimacy – we analyse Chinese social security records and other related data after 1949 by statistical methods. The formula we provide in this study can be used to forecast China's expenditure on its urban social security system, and other scholars can apply our methods to countries in which conditions are broadly similar.     

Negotiating Green Space with Landed Interests: The Urban Political Ecology of Greenway in the Pearl River Delta,China

Land‐centred urbanisation has precipitated shortage of green space in Chinese cities. However, in the Pearl River Delta, an ambitious greenway system has recently managed to flourish. It is intriguing to ask how this has become possible. Informed by the perspective of urban political ecology, this paper finds that the greenway project in the Pearl River Delta represents a set of politically realistic endeavours to alleviate urban green space shortage by adapting to, rather than challenging, powerful landed interests. Three interlocking dimensions about land—municipal land quota, rural land use claims, and real estate development—have influenced why, where and how greenways have been created. Based on these findings, we argue that research on China's politics of urban sustainability necessarily needs to understand the country's land politics.     

The Old and the New: Qualifying City Systems in the World with Classical Models and New Data

Zipf's rank‐size rule, lognormal distribution, and Gibrat's urban growth models are considered as summarizing fundamental properties of systems of cities. In this article, they are used as statistical benchmarks for comparing the shapes of urban hierarchies and evolutionary trends of seven systems of cities in the world including BRICS, Europe, and United States. In order to provide conclusions that avoid the pitfalls of too small samples or uncontrolled urban definitions, these models are tested on some 20,000 urban units whose geographically significant delineations were harmonized in each country over 50 years between 1960 and 2010. As a result, if the models appear not always statistically valid, their usefulness is confirmed since the observed deviations from empirical data remain limited and can often be interpreted from the geohistorical context of urbanism proper to each world region. Moreover, the article provides new free software which authorizes the reproducibility of our experiments with our data bases as well as with complementary data.     

当代国外城市模型研究的进展与未来

由于城市的复杂性、系统性和不可逆性,对城市问题的诊断与解决也必须运用系统化、模型化的方法。本文综述了1980年代以来,城市模型研究在基础理论、模型方法、技术和研究内容上新的发展。认为当代城市模型研究存在的突出问题是:仍然沿用工业化城市的经济社会规律,研究已经被信息化和全球化所深刻影响的城市;复杂性科学理论的综合性不够;GIS与其它模型的集成度有待提高。未来城市模型的研究应着重关注新的城市变化,综合运用复杂性科学的理论与方法,强化以GIS为平台的计算机技术。     

A Measure of Competitive Access to Destinations for Comparing Across Multiple Study Regions

Accessibility is now a common way to measure the benefits provided by transportation–land use systems. Despite its widespread use, few measurement options allow for the comparison of accessibility across multiple urban systems, and most do not adequately control for market competition between demand-side actors and supply-side facilities in localized markets. In this article, we develop a measure of competitive access to destinations that can be used to accurately compare accessibility between regions. This measure stems from spatial interaction modeling and accounts for competition at both the supply and demand sides of analysis, regional differences in transportation networks and travel behavior, and any imbalance between the size of the population and the number of opportunities. We use this method to compute access to employment for Canada's eight largest cities to comparatively examine inequalities in accessibility, both within and between cities, and by travel mode.     

Creating Ecologically Based Land Use and Habitat Maps Quickly and Cheaply to Support Conservation Planning at Local Scales: A New Zealand Example

Effective planning to support and enhance ecological values in sites of conservation interest requires accurate, comprehensive and detailed ecologically based maps and data, not only for the conservation site but for the wider landscape in which such sites are situated. In this paper we present an efficient and low cost method for combining appropriate technologies and available data to produce such maps at a landscape level. This method is described and evaluated using a case study of a land use and habitat map, with an associated geographic information system (GIS). The map was created for the district of Dunedin, New Zealand, an area of approximately 3340 km². This paper demonstrates how the map can be adapted for use by small, locally based conservation organisations that typically do not have the resources to obtain detailed, consistent and comprehensive spatial data for the areas they manage. The example of Orokonui Ecosanctuary is used to illustrate the potential applications of the map including mapping assets and habitats within a site and for exploring the relationship between the Ecosanctuary's internal and external habitats. External habitats can form a vital habitat network for many of the endangered species being reintroduced into the Ecosanctuary as well as a source of threats through potential reinvasion by pests and land use change. Though the mapping method presented in this paper is not necessarily new, it demonstrates the potential for utilising advances in mapping techniques and available data sets to offer a pragmatic support mechanism of practical value for small conservation organisations.     

基于中部地区崛起的城市群整合发展

为协调区域发展,实现经济持续增长,国家作出了"中部地区崛起"这一重大决策。中部6省分别拥有中原城市群、武汉城市圈、长株潭城市群、环鄱阳湖城市群、皖江城市带和太原城市圈等6个城市群,城市群的整合发展在推动中部崛起进程中发挥着越来越突出的主导作用。在对中部地区城市群的现实基础与综合实力进行分析、评价的基础上,提出了基于中部崛起的城市群整合发展的总体意向和要解决的关键问题。整合发展的总体框架为:以武汉城市圈为核心增长板块,中原城市群和长株潭城市群为北、南牵引增长版块,沿交通大动脉京广铁路和长江黄金水道构筑两条南北、东西向城市群发展核心轴带,6个城市群并力互推,形成纵贯中部地区的"倒Y"字形发展格局。     

江苏省城镇化发展协调度评价与地区差异分析

将城镇化分解成人口城镇化、经济城镇化、土地城镇化和社会城镇化4部分,且认为这4部分应处在协调耦合状态,用TOPSIS法对江苏省城镇化发展协调度进行评价,之后对评价结果的地区差异进行分析,以对城镇发展政策制定提供依据。研究表明:常州和扬州在优质协调区;南京、镇江、苏州和无锡在良好协调区,且土地城镇化相对滞后,说明城镇土地高效集约利用;徐州、淮安和南通在基本协调区,徐州与淮安土地城镇化过快,社会城镇化滞后,表明城镇土地粗放低效利用,同时忽视公共服务产品供给,南通土地城镇化滞后,表明城镇扩张缓慢,城镇化的土地代价水平较低;泰州和盐城在轻度失调区,盐城经济城镇化滞后,泰州土地城镇化滞后,土地集约利用强度大,城镇发展选择的是一种精明增长路径;连云港和宿迁在中度失调区,土地城镇化明显快于其它城镇化,城镇发展土地代价水平高,具有相当过渡性损失。