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1.
The aim of this paper is to develop a methodology for identifying various dimensions of the spatial configuration of urban systems in Iran from an interaction perspective. Through the provision of empirical evidence of different types of flows of people including air passenger flows, passenger flows by bus and car, this paper compares the resulting spatial constellations of these flows through the innovative use of indices to systematically describe and measure five dimensions of an urban system’s spatial configuration that include: (1) centrality and dominance of vertices, (2) network cohesion, (3) network strength, (4) network symmetry, and (5) communities and levels. The findings show that although the spatial configurations of different flows are not the same, all were characterized by having a significant distance within a polycentric urban system due to the primacy of the Tehran metropolis. In regard to passenger flows by car and bus, it was found that for various functional regions, there was a balanced distribution of centrality and urban hierarchy evident in Iran. By contrast, air passenger flows were not able to determine centrality within a national urban hierarchy because of the limited distribution of centers for air travel in Iran at higher levels of spatial organization.  相似文献   

2.
The U.S. airline network is one of the most advanced transportation infrastructures in the world. It is a complex geospatial structure that sustains a variety of dynamics including commercial, public, and military operations and services. We study the U.S. domestic intercity passenger air transportation network using a weighted complex network methodology, in which vertices represent cities and edges represent intercity airline connections weighted by average daily passenger traffic, non-stop distance, and average one-way fares. We find that U.S. intercity passenger air transportation network is a small-world network accompanied by dissortative mixing patterns and rich-club phenomenon, implying that large degree cities (or hub cities) tend to form high traffic volume interconnections among each other and large degree cities tend to link to a large number of small degree cities. The interhub air connections tend to form interconnected triplets with high traffic volumes, long non-stop distances, and low average one-way fares. The structure of the U.S. airline network reflects the dynamic integration of pre-existing urban and national transportation infrastructure with the competitive business strategies of commercial airlines. In this paper we apply an emerging methodology to representing, analyzing, and modeling the complex interactions associated with the physical and human elements of the important U.S. national air transport and services infrastructure.  相似文献   

3.
This article analyzes the basic structure of aviation in the Middle East and the development possibilities as a result of Israeli-Palestinian cooperation consequent to the peace process. This paper is a first attempt at estimating the advantages and disadvantages of such cooperation to the Israeli and Palestinian economies. In addition, the research leads to an initial formulation of how to maximize the benefits for both parties.Israeli-Palestinian cooperation offers more than objective economic advantages; such cooperation can also form a functional base for a political-policy framework. In economic terms, both sides can benefit from economies of scale and more efficient utilization of the existing facilities, thus avoiding the waste of valuable resources in establishing two sets of aviation facilities. However these economic criteria are not the only advantage of cooperation. In fact, critical operational and security requirements exist as well, both in terms of passenger security and safety, where air traffic control requiring coordination in a limited airways system. Furthermore, trends in the air travel market point to future bilateral agreements on the basis of blocs of nations and not individual countries. Therefore, Isreali-Palestinian cooperation would enable Israel to maintain the existing framework of favorable bilateral agreement with Europa and the United States.Cooperation of this kind is viable both economically and politically, as it avoids political conflicts by providing infrastructure on an equal basis to the Palestinians, either by lease or purchase of Israeli facilities. The primary advantage of joint ownership is that the Palestinians will save the development and construction costs of new infrastructure, while Israel can both develop the existing infrastructure and free funds for economic development. At the same it is possible to take advantage of economies of scale in order to reap the economic benefits of this process.  相似文献   

4.
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.
Malcolm C. BurnsEmail:
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5.
Mountain hazards such as landslides, floods and avalanches pose a serious threat to human lives and development and can cause considerable damage to lifelines, critical infrastructure, agricultural lands, housing, public and private infrastructure and assets. The assessment of the vulnerability of the built environment to these hazards is a topic that is growing in importance due to climate change impacts. A proper understanding of vulnerability will lead to more effective risk assessment, emergency management and to the development of mitigation and preparedness activities all of which are designed to reduce the loss of life and economic costs. In this study, we are reviewing existing methods for vulnerability assessment related to mountain hazards. By analysing the existing approaches, we identify difficulties in their implementation (data availability, time consumption) and differences between them regarding their scale, the consideration of the hazardous phenomenon and its properties, the consideration of important vulnerability indicators and the use of technology such as GIS and remote sensing. Finally, based on these observations, we identify the future needs in the field of vulnerability assessment that include the user-friendliness of the method, the selection of all the relevant indicators, the transferability of the method, the inclusion of information concerning the hazard itself, the use of technology (GIS) and the provision of products such as vulnerability maps and the consideration of the temporal pattern of vulnerability.  相似文献   

6.
7.
Brian Graham  Jon Shaw   《Geoforum》2008,39(3):1439-1451
This paper addresses the contradictions inherent in the interconnections between air transport liberalization and the economic and environmental dimensions to sustainability from the particular perspective of the dynamic expansion of European low-cost carriers and their networks. The argument considers the incompatibility of environmental sustainability with a business model that promotes rapid growth in air travel without meeting its external costs, but, simultaneously, claims to be socially and geographically inclusive. Moreover, that growth is perceived to be advantageous to strategies promoting national and regional economic growth and, consequently, the provision of low-cost airline services is being promoted by an array of national and local government agencies throughout the European Union. The paper concludes that the low-cost model does not account for its externalities despite air transport being the most environmentally damaging form of transport per passenger-kilometer but is clearly important to economic development at a variety of scales.  相似文献   

8.
A typological framework for categorizing infrastructure vulnerability   总被引:1,自引:0,他引:1  
The concept of vulnerability is increasingly important in engineering and the socio-economic planning sciences, particularly given the enormous costs associated with addressing it. The ability to identify and mitigate vulnerabilities is extremely challenging because it is influenced by a complex and dynamic set of interacting factors that can compromise social, economic and infrastructure systems. Where the latter is concerned, the ability to assess infrastructure vulnerability involves the consideration of a range of physical, operational, geographical and socio-economic characteristics. In this paper, significant elements of infrastructure vulnerability are identified and discussed with a focus on their intrinsic spatial nature and their propensity to interact across space. Further, the developed typology of vulnerability outlined in this paper emphasizes the need to ensure that policy, planning and disaster mitigation efforts are strongly integrated at global, regional and local levels.  相似文献   

9.
为面向冰冻圈服务功能核算,采用投入产出法和ESDA分析,评估了2012-2016年间西藏自治区公路交通基础设施建设对经济增长的贡献程度,并解释作用机理,在此基础上运用GlobalMoran's I指数和Local Moran's I指数作出空间效应分析。结果表明:公路建设直接和间接创造的增加值对区域经济增长具有巨大的促进作用,在空间分布上,各地市公路建设对经济增长的贡献度在自治区范围内存在差异,但未呈现出固定的变化趋势。由于公路对经济增长巨大的溢出效应,应高度重视公路等交通基础设施建设,加大投资力度,拓展通达里程与空间分布,在冰冻圈服务功能核算中纳入交通设施建设的社会经济效益,同时充分考虑冰冻圈气候变化等因素对交通基础设施的危害影响,确保区域经济保持平稳快速增长。  相似文献   

10.
Rock minerals such as dimension and crushed stones and sands and gravels (aggregates) are indispensable materials for the building and construction industries. The growth in demand for these resources causes intensification of mining operations (and their consequent environmental impacts) and transport problems in regions abundant in rock minerals. The balanced management of these resources by regional policy-makers is difficult as it requires, among other things, comprehensive and up-to-date information on the spatial distribution and temporal changes of available reserves, demand, production, and transport. This information can be provided by means of spatial and temporal analyses through geographic information systems (GIS). In this research, the focus is on the following aspects of rock mineral (aggregates) resources and mining management in the context of regional spatial planning in the example region of Lower Silesia in Poland: the spatial and temporal changes in distribution and intensity of mining, the availability of economic reserves in active mines, the magnitude and distribution of road transport flows of aggregates, the potential of railways as an alternative means of transport, and the valorisation of undeveloped aggregates deposits to assess their suitability for future use. For the purposes of this study, cartographic models have been developed using GIS to facilitate analyses of these mineral resources, mining, and transport. The results of these analyses provide current and comprehensive information on the state of aggregates mineral resources, production and transport in the Lower Silesia region. They also give an insight into availability of rock mineral resources for the future. Knowledge of these processes is important for spatial development planning, especially physical infrastructure, conducted by national, regional, and local governments.  相似文献   

11.
In South Africa attempts are being made to address the socio-spatial distortions of the apartheid era through a more equitable distribution of resources, and the re-drawing of municipal geographical boundaries. However, boundaries are not neutral geographic lines. Boundary changes are often associated with a redistribution of political power and resources. The aim of this paper is to analyse the effects of the contemporary territorial and administrative restructuring on urban dynamics in South Africa. More specifically, the focus is on how the process of territorial restructuring impacted on metropolitan areas as well as on secondary cities and their hinterlands. Examining and elucidating the manner in which various social, economic and political forces have manifested themselves in the process of boundary delimitation in a major metropolitan centre as well as adjacent rural areas is a central theme of this paper. There were considerable contestations over the delimitation of new local government boundaries. Affluent metro authorities like that in Durban were opposed to the spatial extension of their boundaries because of the costs of the providing services and infrastructure in the deprived margins. Similarly, there was concern that incorporation of rural areas will result in increased municipal service charges being imposed on these communities. Tensions were heightened between urban and rural regions because traditional leaders believed that their territorial jurisdiction and authority were being undermined. In other parts of the country, the merger of traditionally white and black fragments of secondary cities often resulted in many black locations continuing to be marginalized. There appears to be neither the political will nor the economic capacity to upgrade these zones of marginalized urban communities. While the Municipal Demarcation Board was largely successful in eliminating the political geography of apartheid at a macro- scale, this paper suggests that the greater challenge for government and policy makers is to reduce the socio-spatial and economic inequalities which appears to be still very high and perhaps increasing. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

12.
Jonathan Rutherford 《Geoforum》2008,39(6):1871-1883
This paper focuses on the extent to which recent infrastructure-oriented urban developments in Stockholm concord with various aspects of the ‘splintering urbanism’ thesis of Graham and Marvin. This contextualisation allows us to extend their work empirically and conceptually. In the first instance, we study a particular case of the decline of a unitary networked city (in an urban context largely absent from their book). In the second instance, we develop their notion of ‘unbundling’ to capture not just core changes in the organisation of infrastructure provision, but an overarching disjunction of the established nexus between networks, planning and social welfare in the city. This disjunction operates through interlinked transformations concerning, for example, privatisation and outsourcing in network services, separation of infrastructure planning from broader urban planning, contradictions between the environmental and social mandates of infrastructure, and a (prospective) curtailment of the redistributive, social role of essential network service provision. We conclude nonetheless that this ‘destructive’ moment of unbundling has not so far been pursued by more explicitly ‘creative’ urban fragmentation strategies, due largely to the vestiges of a socio-political consensus based around redistribution and equality. In this respect, the Stockholm case pleads for a conception of ‘splintering’ as a dynamic and multi-stage process which is not only always ongoing, unstable and incomplete, but also non-linear and open to resistance/regulation.  相似文献   

13.
This paper analyzes how Mexican hometown associations in New York City practice solidarity so that they might best meet the needs of the transnational communities that they serve. Commonly formed by immigrants in the United States, hometown associations are organizations which send money collectively to their home countries, supporting public infrastructure and community projects. Scholars have debated both the merits of remittance programs that channel migrant funds as economic development and the agency of immigrant economies in neoliberal development structures. Through primary data collected from interviews in New York City, I review the frustrations that hometown associations have with one such program: Mexico's programa tres por uno para migrantes. Concurrently, I examine how the same hometown associations engage ethical economic practices of collective remittance sending and community service provision in New York City. Drawing on feminist literature on diverse economies, I argue that the solidarity work of hometown associations disrupts the dominant remittance as development discourse. Migrants are not content to participate in tres por uno and through practicing solidarity they distance themselves from this neoliberal policy.  相似文献   

14.
Jose Julio Lima   《Geoforum》2001,32(4):125
In the second half of the 1990s, socio-spatial segregation increased in Brazilian cities, accentuating inequity among social groups. Using a combination of space syntax techniques and statistical analysis, this paper explores locational differences in central and peripheral portions of Belém. The analysis shows how socio-spatial segregation was made more pronounced by relationships between urban form, infrastructure provision and locational values. Social groups' opportunities in the city are suggested to be limited by features of its urban form, associated with infrastructure provision, especially for groups unable to take advantage of intra-urban accessibility. The paper also discusses the findings of the study in relation to the Brazilian urban context at the end of the 1990s.  相似文献   

15.
The Tamale Metropolitan Area (TMA), as a low-income city in a heavily indebted poor country, is at the first stage of the urban environmental transition where most of the environmental problems tend to occur close to the home. Some of the more severe household environmental problems are poor housing, inadequate potable water supply, unsanitary conditions, uncollected garbage, indoor air pollution and pest infestation. Those usually exposed to these environmental burdens are the less wealthy households who have benefited less from development planning and infrastructure provision. Using questionnaire survey and focus group discussions, this study explored the environmental anxieties of households in the metropolis. A stratified sample of residential areas of the city was employed, and the study is able to examine city-wide disparities. The results indicate that problems of water supply are the concern of all groups. Sanitation and garbage disposal services are problems faced mainly by the poor in low-income areas. Other problems faced by the poor are overcrowding, indoor air pollution and pest infestation, but these problems are not highlighted by the poor reflecting a misplaced lack of concern for these problem areas and ignorance of the health risks posed by these hazards. The finding suggests a considerable demand for improvements in environmental service provision and a general willingness to pay for such improvements.
Issaka Kanton OsumanuEmail:
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16.
The development corridor concept has been regarded as an important development instrument in spatial planning and geography for many decades. Expanding literature on the theme indicates that development centres or nodes play an important role in the establishment of such corridors. Flows of goods and information between such centres are essential in creating conditions that are potentially favourable for further urban development along the communication axes connecting such centres. Combined, the various nodes form a unique flexible exchange environment allowing for dynamic synergies of interactive growth to achieve scope economies aided by fast and reliable corridors of transport and communication infrastructure. In the South African development sphere, there is strong belief that functional relationships between nodes can play a decisive role in the establishment of development corridors. The research showed that the degree to which economic activities are concentrated in the greater Gauteng region; the resulting current or emerging multinodal structural composition; and the flows of economic activities between the various nodes result in the creation of development corridors that channel and focus economic growth between networks of cities. This confirms the importance of corridors as spatial and economic development instruments. The research concluded that the core cities of Johannesburg and Pretoria are the central driving force in corridor development in Gauteng. They feature as the most dominant nodes, exerting great forces of attraction on the distribution of development and economic growth in the region. The research also suggests a degree of polycentrism whereby economic growth is channelled between networks of cities, however development potential is most favourable in areas in close proximity to primary centres and tends to be functionality driven.  相似文献   

17.
The calculation of air passenger flow density and the recognition of heat airspace in terminal areas of large hub airports is a new challenging research in the intelligent era, that is, using big data can automatically generate air passenger flow and basic rules. Aimed for the air passenger flow density in airport and its relationship between occupation and airspace, based on the establishment of the Beijing International Airport 1 h flight, which consists of basic parameters-latitude, longitude and height, additional parameters-dogleg and speed of trajectories, time parameters, a spatio-temporal data set by clustering trajectories and calculation of aircraft trajectories points was made up. Then, heat cloud map of flight trajectories under 4D conditions was generated. Cell was used to identify the basic parameters and time parameter of heat airspace; grid graphs of flight trajectories were used to identify additional parameters and explain the influence on heat airspace; probability fitting graphs were used to verify the accuracy of 4D results. The conclusion is as follows: there are two areas of Beijing International Airport, which have the high density and at two different heights there also exist hot peaks; flight trajectories and speed of trajectories also affect the heat airspace. The variation of heat airspace caused by different flight occupancy time in 4D recognition was revealed. The method realized the 4D heat cloud map of flight trajectories, which is better for detailed and accurate information construction, expression of spatial changes, and more the parameters of density and visualization of temporal and spatial range, which can assist the automatic dynamic airspace sectorization and decision making on airspace allocation, and also have a definite reference meaning in alleviating the contradiction between the current air traffic demand and limited airspace.  相似文献   

18.
Simon Mariwah 《GeoJournal》2018,83(2):223-236
While inadequate water and sanitation services have both been implicated in a number of mortality and morbidity situations all over the world, the improvement in sanitation provision lags far behind that of water. This paper therefore seeks to examine the spatial variation in sanitation provision in Ghana and assess the factors that have contributed to the low investment in sanitation infrastructure as well as how sanitation can be improved. It revealed that the low sanitation has its roots in somewhat complicated political, institutional, economic and socio-cultural factors, including inadequate political commitment, poor monitoring, higher negative externalities associated with sanitation compared with water, and low sanitation demand resulting from poor social marketing for sanitation. Sanitation should therefore be marketed as a concept that has public health benefits and not merely as a toilet facility. Proper social marketing for sanitation and scaling up the community-led total sanitation approach should be pursued to stimulate individual demand for private sanitation.  相似文献   

19.
As containerization enters its peak growth years, its potential future developments over maritime and inland freight transport systems are being questioned. A series of issues can either further accelerate the adoption of containerization worldwide or, alternatively, could impose an upper limit to the extraordinary contribution that containers have implied for logistics systems and global commodity chains. These mainly include macro-economic, technical/operational and governance factors. Future containerization will be largely determined by interactions within and between four domains ranging from a functional to a spatial perspective. The logistical domain involves the functional organization of transport chains and their integration in supply chains. The transport domain involves the operation of transport services and intermodal operations. The infrastructural domain involves the provision and management of basic infrastructure for both links and nodes in the transport system. The locational domain relates to the geographical location of nodes and sites in the economic space and forms a basic element for their intrinsic accessibility in terms of centrality or intermediacy. It is underlined that the future of containerization will dominantly be shaped by inland transport systems.  相似文献   

20.
Although the number of directions which geographical research on transport is taking has recently increased, the extent to which transport geography capitalises on theoretical advancements made in other sub-disciplines of human geography is still fairly limited. This especially pertains to economic geography which, in contrast to the predominantly positivist and quantitative transport geography, has developed over the last few decades a more post-positivist and qualitative profile. By means of focusing on passenger air transport – one of the most neglected industries in economic geography – this paper aims to help bridge this gap. Three under-researched aspects of air transport are identified and a combination of two economic-geographical approaches – global production networks (GPN) and evolutionary economic geography (EEG) – is advocated as a useful conceptual basis for further, more qualitative and more critical research on this dynamic sector. The paper argues that GPN and EEG would help research on air transport to: (1) employ network thinking beyond the infrastructural understanding of networks of air connections and thus better explain the multi-actor nature of the aviation sector, (2) complement the research on supra-national and national regulatory frameworks with more attention to the array of sub-national environments that shape the aviation industry ‘from below’, and (3) explore how the relations between aviation and economic development are moulded by different place-specific institutional factors. To lay foundations under further research the paper conceptualises the aviation industry as a global production network and uses the example of Polish passenger air transport to highlight the paper’s key empirical implications.  相似文献   

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