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1.
This article borrows a statistical method from physical geography—topographical prominence—to suggest a new technique for measuring the relative significance or rank of population centers. Unlike raw population measures, prominence gives consideration to both the spatial intensity of concentrated population areas as well as the spatial dependence or independence of neighboring settlement clusters in relation to one another. We explain how to apply the topographic prominence calculation method to gridded population data and examine its practical utility through case studies of several U.S. states. We then discuss some ways in which parametric choices about point-to-surface transformations can result in considerably different outcomes and offer further suggestions for conceptualizing and measuring population center significance. 相似文献
2.
Until recently the traditional spatial configuration of the European geography was based upon the core-periphery model. The
‘pentagon’, broadly defined as lying between London, Paris, Milan, Munich and Hamburg, was seen as the core area characterised
by having the highest concentration of economic development in the European Union (EU), with the remainder of the European
territory viewed as peripheral, albeit to varying degrees. In a number of cases such peripheral areas equated with clear regional
disparities. The elaboration of the European Spatial Development Perspective (ESDP) (CEC, European spatial development perspective, towards balanced and sustainable development in the territory of the
European Union, 1999) challenged this core-periphery model. European spatial planning policies, aimed at encouraging social
and economic, and with ever increasing importance, territorial cohesion, seek amongst other aspects to encourage the development
of a balanced and polycentric urban system. This paper adopts a network analysis approach to the analysis of air passenger
flows between some 28 principal European metropolitan urban regions. The evaluation of these flows contributes to an enhanced
comprehension of the spatial dynamics of the European metropolitan territory which goes beyond that deriving from the more
standard analyses of the individual components of the urban system. Several indicators are used, deriving from gravitational
modelling techniques, to analyse the complexity of the air passenger flows. A multidimensional scaling (MDS) technique is
introduced in order to interpret and visualise the resulting spatial configuration and positioning of the different metropolitan
centres within the conceptual European ‘space of air passenger flows’, thereby contrasting with the more traditional map-based
geographical image of Europe, based upon Cartesian coordinates.
相似文献
Malcolm C. BurnsEmail: |
3.
In this paper it is argued that the re-establishment of a metropolitan government in the Greater Copenhagen Area in 2000 (Greater
Copenhagen Authority) is not to be seen as a return to the kind of regional, coordinative authority (Greater Copenhagen Council)
that was abolished in the Thatcherite climate of the 1980s. Throughout the 1980s and 1990s new forms of urban governance,
entrepreneurialism and a higher national priority to the capital region were introduced, which changed the conditions under
which the new metropolitan government is operating. This `contextualization' of the analysis of the two generations of metropolitan
government points to the fact that typologies of metropolitan government, such as the one put forward by Sharpe (1995), often
lacks analytical cogency.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
4.
Traditional models of urban development are no longer adequate to describe current metropolitan transformations. These are
now at the centre of a debate concerning management and administration. In Italy, delays in resolving problems of urban and
metropolitan government, despite the legal framework provided by Law 142/90, have weighed heavily on the larger urban areas
of the country: Rome, Naples, Milan, which have not been able to tackle the issue of metropolitan government. Recent legislation,
while not providing a pre-defined institutional solution, allows separate administrative districts to collectively establish
metropolitan institutions of `variable geometry'. The Milan urban area is not one city, but a system of mutually-dependent
cities, linked to each other and the rest of the world by a transport network still requiring much investment. The vitality
of its economic structure (especially its small firms) is held back by seriously inadequate infrastructure and low external
economic efficiency. The provincial capital may boast `historic centrality' but the most interesting potential for development
is to be found on the periphery and in the administrative districts immediately surrounding it, in the recovery of derelict
industrial areas and dormitory towns established in the 1950s and 1960s, especially to the north. Recovery of derelict areas,
green areas, and better transport links within the urban area and with the outside world are the key elements in the reorganization
of `Greater Milan'. In this situation of rapid transformation the most appropriate political strategies involve negotiated
planning.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
5.
国外大都市区规划体系评述 总被引:10,自引:1,他引:10
本文探讨了国外大都市区在规划编制中的一些最新做法和特点,包括规划负责机构、规划组织体系、规划编制大纲三个方面,并介绍了美国纽约、英国伦敦和日本近畿圈规划的特点。由于各国管理制度的差异性和大都市区组织结构的多样性,国外大都市区的规划呈现不同特点和效果。 相似文献
6.
鞍山市西郊区水位预测 总被引:2,自引:0,他引:2
根据鞍山市西郊区水文地质条件,建立了双层渗流二维平面系统的数学模型:应用Galerkin有限元法求解模型,从模型的计算结果可见该区观测点水位绝对误差较小,达到了规范要求的计算精度,同时,在此区内有一个大漏斗,在东南的铁西一带也有一个小漏斗。由于铁西一带是主要开采水源区,开采水量较大,所以漏斗逐渐向外扩大且水位有明显下降的趋势。这一变化规律与实际水位一致,说明计算水位基本上反映了实际水位空间变化的规律。因此根据模拟参数利用此模型对该地区进行了水位预测,共预测了四年的水位状况,并依据水位的预测结果对该区的水资源开发利用提出了合理建议。 相似文献
7.
Metropolitan growth and labor markets in Mexico 总被引:1,自引:0,他引:1
Adrian Guillermo Aguilar 《GeoJournal》1997,43(4):371-383
The objective of this paper is to examine the main changes in the metropolitan labor markets associated with economic restructuring in Mexico during the late 1980s and beginning of the 1990s. The analysis refers particularly to the four largest metropoles of the country, Mexico City, Guadalajara, Monterrey and Puebla, looking for common characteristics in their emergent employment structures now strongly differentiated in terms of rewards, stability in employment relations and conditions of access to jobs. The analysis reveals that largest metropolitan areas have been the most profoundly affected by the economic restructuring resulting from globalization, through a rapid de-industrialization and the expansion of the tertiary sector. Metropolitan labor markets in Mexico, at the time that show signs of social polarization in the formal sector, put in evidence a general process of precarization – less labor stability, replacement of permanent by part-time jobs, and increasing subcontracting –, segmentation of the labor force, and an increasing informal conditions of economic activities with small businesses and unskilled, temporarly and poorly paid jobs. The labor force segmentation and its more precarious and casual conditions are mostly explained by the impact of recent neoliberal policies, and recurrent economic crisis during the 1980s and 1990s which highly contributes to social inequality. 相似文献
8.
In a recent issue of Urban Geography (2001) , a number of key players in the 1960s and 1970s school of quantitative urban geography (called Chicago II in this article) set out some of the approach's key methodological premises and assessed its influence in the wider arena of urban studies. At about the same time, the 1920s and 1930s Chicago School of urban sociology (called the Chicago School in this article) was being reassessed in France ( Huet 2000 ), and deconstructed in Los Angeles ( Dear 2001 ). In this article, we outline a selection of basic models of urban space proposed by the Chicago School and further elaborated by Chicago II. We then consider certain aspects of three important critiques: humanist/aesthetic, Marxist, and postmodern. We argue that none of these invalidates the Chicago II approach to the study of urban areas, and we demonstrate its resilience and usefulness by way of the empirical example of Montreal. Though the results are of interest in their own right, the principal purpose of the analysis is to illustrate the type of insight that a structured quantitative approach provides and the way this approach rests on a theoretical understanding of processes at work in cities. We conclude by arguing that the humanist and Marxist critiques shed important light upon the possibilities and limits of the Chicago II approach, but that the postmodern claim that the spatial development of urban areas is not structured by at least some general processes is inaccurate. 相似文献
9.
What kinds of places have high entrepreneurial activities? There has been an emerging body of studies about so-called entrepreneurship ecosystems, but virtually all of the past studies have examined this question from a perspective of which metropolitan areas have higher entrepreneurial activities. In this article, we examine the intrametropolitan scale at the Census tract level. By analyzing thirty metropolitan areas to extend external validity, we demonstrate the concentration of high-growth firms in specific employment nodes in both urban and suburban parts of each metropolitan area. Significant correlations exist between place-based vibrancy indicators and high-growth firm concentrations. 相似文献
10.
北京城郊近地层湍流实验观测 总被引:13,自引:2,他引:13
本文利用两台FA-11超声风速温度仪于1992年3月到4月间在北京325 m气象观测塔47 m和120 m两个高度观测到的风速三个正交分量以及声虚温的湍流脉动资料,计算和分析了北京城郊粗糙下垫面近地层湍流特征量及其日变化,无量纲垂直速度和声虚温的方差随稳定度的变化,风速分量和温度的归一化湍流能谱以及动量和热通量的互谱及其随稳定度的变化。并且与平坦均一下垫面近地层湍流观测的结果进行了对比。 相似文献