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1.
This paper investigates place and positionality in the regional novel against a background of evolving trends in geographical scholarship of place and placelessness. In re‐examining the representation of Glasgow in the urban regional novel, it proposes that a qualitative difference exists between rural and urban epistemologies which relates to the profoundly temporal essence of ‘cityness’. Aspects of both multi‐dimensionality in urban time‐space and of the city as the locus for working‐class oppression are reviewed in the context of a selection of urban imaginings.  相似文献   

2.
By exploring the Europeanization of current practices of regional spatial planning, this article sets out to demonstrate the evolution of the European integration project. Specifically, by creating spaces of engagement to which the local and regional actors are “forced” to adapt, the emergence of European spatial planning has made planning practices at the regional level more complex and complicated. As such, the present study contributes to the current understandings of Europeanization by exploring the European integration process through the geographical conceptualizations of space and scale. These conceptualizations are used to illustrate the multidimensionality, complexity and subtlety of the geographies of Europeanization. The empirical investigations show that regional and local spatial policies are strongly engaged – both explicitly through the “technicalities” and implicitly through the “mentalities”– to the spaces of Europeanization. The engagement affects the effectiveness of sub‐regional spatial planning by promoting mismatches between the strategic frameworks and the material practices of the policy. Overall, the article illustrates that the geographies of Europeanization are continuous processes, which take place – often unrecognizably – in manifold discursive and material practices in various geographical contexts.  相似文献   

3.
Spatial co‐location patterns are useful for understanding positive spatial interactions among different geographical phenomena. Existing methods for detecting spatial co‐location patterns are mostly developed based on planar space assumption; however, geographical phenomena related to human activities are strongly constrained by road networks. Although these methods can be simply modified to consider the constraints of networks by using the network distance or network partitioning scheme, user‐specified parameters or priori assumptions for determining prevalent co‐location patterns are still subjective. As a result, some co‐location patterns may be wrongly reported or omitted. Therefore, a nonparametric significance test without priori assumptions about the distributions of the spatial features is proposed in this article. Both point‐dependent and location‐dependent network‐constrained summary statistics are first utilized to model the distribution characteristics of the spatial features. Then, by using these summary statistics, a network‐constrained pattern reconstruction method is developed to construct the null model of the test, and the prevalence degree of co‐location patterns is modeled as the significance level. The significance test is evaluated using the facility points‐of‐interest data sets. Experiments and comparisons show that the significance test can effectively detect network‐constrained spatial co‐location patterns with less priori knowledge and outperforms two state‐of‐the‐art methods in excluding spurious patterns.  相似文献   

4.
Spatial Empirics for Economic Growth and Convergence   总被引:10,自引:0,他引:10  
This paper suggests some new empirical strategies for analyzing the evolution of regional income distributions over time and space. These approaches are based on extensions to the classical Markov transition matrices that allow for a more comprehensive analysis of the geographical dimensions of the transitional dynamics. This is achieved by integrating some recently developed local spatial statistics within a Markov framework. Insights to not only the frequency with which one economy may transition across different classes in the income distribution, but also how those transitions may or may not be spatially dependent are provided by these new measures. A number of indices are suggested as ways to characterize the space‐time dynamics and are illustrated in a case study of U. S. regional income dynamics over the 1929–1994 period.  相似文献   

5.
Despite reaching a point of acceptance as a research tool across the geographical and social sciences, there remain significant methodological challenges for agent‐based models. These include recognizing and simulating emergent phenomena, agent representation, construction of behavioral rules, and calibration and validation. While advances in individual‐level data and computing power have opened up new research avenues, they have also brought with them a new set of challenges. This article reviews some of the challenges that the field has faced, the opportunities available to advance the state‐of‐the‐art, and the outlook for the field over the next decade. We argue that although agent‐based models continue to have enormous promise as a means of developing dynamic spatial simulations, the field needs to fully embrace the potential offered by approaches from machine learning to allow us to fully broaden and deepen our understanding of geographical systems.  相似文献   

6.
The census is the traditional source of population figures at various levels. Census figures however are technically outdated immediately they are released because planners require figures for the present and possibly for future dates. In an attempt to meet this demand different organisations and researchers produce population estimates and projections. These estimates however are usually at higher geographical levels and often do not meet the planning needs of administrators at lower geographical levels. This study extends a top‐down estimation method to an African country by estimating the mid‐2014 population at ward level in South Africa. The study used the 2011 South Africa Census to estimate current levels of fertility, mortality as well as current trends in net migration at a higher geographical level. Historical trends in fertility and mortality were based on the 1996 Census, 1997 and 1998 October Household Surveys as well as the 2007 Community Survey data. The results indicate that that 20 of the largest wards as at mid‐2014 were located in South Africa's metropolitan areas. Nineteen of the 20 largest wards are currently growing at a rate of over 4% per annum and if this trend continues, eighteen of these wards will double their current population size in less than 15 years.  相似文献   

7.
This article discusses how standard spatial autoregressive models and their estimation can be extended to accommodate geographically hierarchical data structures. Whereas standard spatial econometric models normally operate at a single geographical scale, many geographical data sets are hierarchical in nature—for example, information about houses nested into data about the census tracts in which those houses are found. Here we outline four model specifications by combining different formulations of the spatial weight matrix W and of ways of modeling regional effects. These are (1) groupwise W and fixed regional effects; (2) groupwise W and random regional effects; (3) proximity‐based W and fixed regional effects; and (4) proximity‐based W and random regional effects. We discuss each of these model specifications and their associated estimation methods, giving particular attention to the fourth. We describe this as a hierarchical spatial autoregressive model. We view it as having the most potential to extend spatial econometrics to accommodate geographically hierarchical data structures and as offering the greatest coming together of spatial econometric and multilevel modeling approaches. Subsequently, we provide Bayesian Markov Chain Monte Carlo algorithms for implementing the model. We demonstrate its application using a two‐level land price data set where land parcels nest into districts in Beijing, China, finding significant spatial dependence at both the land parcel level and the district level.  相似文献   

8.
Achieving the greatest coverage using limited resources has long been a concern for regional planners. Since the 1970s, a variety of models have been studied and relied upon. Finding ways to best represent geographical space remains a challenge to many researchers. Solutions suggested by models vary greatly with different space representation schemes. For example, in the past, points have been widely adopted to represent spatial demand for coverage. However, this simple abstraction of geographical space could bring about inaccuracies and uncertainties, and often compromises its solution quality. Considering that demand can be area based, which is beyond points, objects of different shapes have been proposed as an alternative for representation. With advances in geographic information systems (GISs), the new representation scheme using objects has recently received much attention. Compared with the straightforward point‐based abstraction, spatial object representation poses considerable challenges to both model formulation and computation capability. This article revisits model development for the problem of regional coverage maximization and proposes a new formulation where coverage of spatial demand is implicitly modeled. Model testing is conducted through an application to warning siren siting in Dublin, Ohio, which has been studied by other researchers. Results demonstrate the effectiveness of the new model when compared with the existing models. Uno de los objetivos comunes en la planificación regional es lograr la máxima cobertura de un servicio con recursos limitados. Desde la década de los 70s se vienen utilizado una serie de modelos conocidos. Sin embargo, la representación adecuada del espacio geográfico de dichos modelos sigue siendo un problemática para muchos investigadores. Las soluciones derivadas de los modelos varían considerablemente de acuerdo a los diferentes esquemas de representación utilizados. El uso de puntos por ejemplo, ha sido ampliamente utilizado en el pasado como esquema de representación espacial de la demanda a ser cubierta por el servicio. Sin embargo, esta simple abstracción del espacio geográfico puede provocar imprecisiones e incertidumbres que a menudo afectan la calidad de la solución matemática del modelo. En contraste, si la demanda se define como un área que abarca una extensión que va más allá de los puntos es posible proponer—como lo han hecho varios recientemente‐ el uso de objetos espaciales (de formas variadas) como una alternativa sensata de representación. Con los avances en los sistemas de información geográfica (SIG), este nuevo esquema de representación ‐que usa objetos especiales‐ han recibido considerable atención. En contraste con esquemas sencillos como el basado en puntos, la representación de objetos espaciales presenta varios desafíos en cuanto a la formulación y computación del modelo. El presente artículo reseña el desarrollo del modelamiento del problema de máxima cobertura regional (problem of regional coverage maximization) y propone una nueva formulación en la cual la cobertura de la demanda en el espacio es modelada de manera implícita. La evaluación del modelo se realiza a través de una aplicación que usa datos de la ubicación sirenas de alarma en Dublín, Ohio. Los resultados demuestran la eficacia del nuevo modelo en comparación con los modelos existentes. 利用有限资源实现最大覆盖一直广受区域规划者关注。自20世纪70年代以来,发展了大量针对这一问题的模型研究。寻找最佳的地理空间表达方式仍是研究者面临的一大挑战。不同模型对于不同的空间表达模式变化很大。比如过去空间覆盖需求多采用点集表达。然而,这种简单的地理空间抽象方法可能会引起不精确性和不确定性,通常也会导致解决方案质量下降。考虑到需求可能是基于区域而非基于点,不同形状的对象已经被当作空间表达可替代的方式。随着GIS技术的进步,基于对象空间表达的新方案近来备受关注。较之于直接基于点的空间抽象,空间对象表达在模型的形式化表达和计算性能上均面临相当大的挑战。本文回顾了区域最大覆盖问题模型研究的发展历程,提出了一个新的蕴含空间覆盖建模需求的模型。以曾被诸多学者研究过的俄亥俄州都柏林的报警器选址问题为例对模型进行检验,结果显示新模型较现有模型更为有效。  相似文献   

9.
马双  曾刚 《人文地理》2016,31(1):116-123
知识溢出的本地化现象揭示了地理边界的限制机理,然而越来越多的研究表明知识溢出也可发生在远距离的空间范围内。本文以我国装备制造业为例,采用扩展的知识生产函数方法探讨大学和科研机构的知识溢出对区域创新的影响。结果表明,大学和科研机构能够产生强烈的本地和跨区域的知识溢出效应,地理空间和创新网络在跨区域知识溢出中扮演重要角色。其中,产学研合作产生的知识溢出不仅局限于区域尺度,也发生在更高的国家尺度;在地理空间的制约影响下,高素质劳动力的流动对区域创新的影响十分显著且稳定,而大学和科研机构的衍生溢出机制则不那么明显,其原因可能与空间尺度选择有关。  相似文献   

10.
侯甬坚 《人文地理》1992,7(3):56-63
运用空间地理规律探讨历史区域的空间发展过程,在古代中国具有十分良好有利的客观条件。本文基于较大空间尺度和较长历史时限,针对区域地理诸多分异现象的发生和变化,系统阐述了这一规律的三个方面(纬度地带性规律、经度省性和垂直地带性规律),在不同区域或地带空间发展过程中突出的表现特点和影响形式。  相似文献   

11.
Although developed societies are becoming increasingly ethnically diverse, relatively little research has been conducted on geographies of mixed‐ethnic unions (married or cohabiting). There is some recent evidence from the US that mixed‐ethnic couples are more likely to be found in mixed‐ethnic neighbourhoods, but this research is based on cross‐sectional data. Therefore it is not possible to determine whether mixed‐ethnic couples are more likely to form in mixed‐ethnic neighbourhoods or whether they are more likely to move there. Our longitudinal analysis allows us to tease out the relative importance of these two processes, furthering our understanding of the formation of mixed‐ethnic unions. Using data from the Office for National Statistics Longitudinal Study we examine neighbourhood effects on the formation of mixed‐ethnic unions in England and Wales. We find that mixed‐ethnic unions are more likely to form in neighbourhoods with low concentrations of co‐ethnic population. The results from this study lend support to the contact theory that geographical proximity to other ethnic groups enhances mutual understanding between people from different ethnic groups and could lead to the development of intimate partnerships.  相似文献   

12.
Joe Painter 《对极》2010,42(5):1090-1118
Abstract: Territory is the quintessential state space and appears to be of growing political importance. It is also a key concept in geography, but it has not been subject to as much critical attention as related geographical terms and remains under‐theorised. Taking my cue from Timothy Mitchell's suggestion that the state should be understood as the effect of social practices, I argue that the phenomenon that we call territory is not an irreducible foundation of state power, let alone the expression of a biological imperative. Instead, territory too must be interpreted principally as an effect. This “territory‐effect” can best be understood as the outcome of networked socio‐technical practices. Thus, far from refuting or falsifying network theories of spatiality, the current resurgence of territory can be seen as itself a product of relational networks. Drawing on an empirical case study of the monitoring of regional economic performance through the measurement of gross value added (GVA), I show that “territory” and “network” are not, as is often assumed, incommensurable and rival principles of spatial organisation, but are intimately connected.  相似文献   

13.
Thermohaline convection of subsurface fluids strongly influences heat and mass fluxes within the Earth's crust. The most effective hydrothermal systems develop in the vicinity of magmatic activity and can be important for geothermal energy production and ore formation. As most parts of these systems are inaccessible to direct observations, numerical simulations are necessary to understand and characterize fluid flow. Here, we present a new numerical scheme for thermohaline convection based on the control volume finite element method (CVFEM), allowing for unstructured meshes, the representation of sharp thermal and solute fronts in advection‐dominated systems and phase separation of variably miscible, compressible fluids. The model is an implementation of the Complex Systems Modelling Platform CSMP++ and includes an accurate thermodynamic representation of strongly nonlinear fluid properties of salt water for magmatic‐hydrothermal conditions (up to 1000°C, 500 MPa and 100 wt% NaCl). The method ensures that all fluid properties are taken as calculated on the respective node using a fully upstream‐weighted approach, which greatly increases the stability of the numerical scheme. We compare results from our model with two well‐established codes, HYDROTHERM and TOUGH2, by conducting benchmarks of different complexity and find good to excellent agreement in the temporal and spatial evolution of the hydrothermal systems. In a simulation with high‐temperature, high‐salinity conditions currently outside of the range of both HYDROTHERM and TOUGH2, we show the significance of the formation of a solid halite phase, which introduces heterogeneity. Results suggest that salt added by magmatic degassing is not easily vented or accommodated within the crust and can result in dynamic, complex hydrologies.  相似文献   

14.
社会、经济要素的空间离散化是精细化县级主体功能区划的重要需求,本文提出了一种基于模糊关系识别的空间数据离散化方法。该方法利用广义权距离实现对专家知识与多系统分层要素的综合集成,并通过建立待离散化要素与其影响指标的模糊关系识别模型,获得空间离散化权重。以2009年江苏省阜宁县人口、GDP以及经济发展水平的空间离散化为例进行实例分析。结果显示,本文提出的空间离散化方法具有较好的准确性与可信度,可较好揭示各影响要素对待离散要素的空间影响。  相似文献   

15.
The generation of computational meshes of complex geological objects is a challenge: their shape needs to be retained, resolution has to adapt to local detail, and variations of material properties in the objects have to be represented. Also mesh refinement and adaptation must be sufficient to resolve variations in the computed variable(s). Here, we present an unstructured hybrid finite element, node‐centred finite‐volume discretization suitable for solving fluid flow, reactive transport, and mechanical partial differential equations on a complex geometry with inhomogeneous material domains. We show that resulting meshes accurately capture free‐form material interfaces as defined by non‐uniform rational B‐spline curves and surfaces. The mesh discretization error is analysed for the elliptic pressure equation and an error metric is introduced to guide mesh refinement. Finite elements and finite volumes are represented in parametric space and integrations are conducted numerically. Subsequently, integral properties are mapped to physical space using Jacobian transformations. This method even retains its validity when the mesh is deformed. The resulting generic formulation is demonstrated for a transport calculation performed on a complex discrete fracture model.  相似文献   

16.
At the time of the discovery of the Newport medieval ship, it proved impossible to date the timbers used in its original construction through dendrochronology. Associated British timbers and artefacts provided dating to the mid 15th century, with the latter pointing to strong Iberian connections. The development of regional oak ring‐width chronologies in the Basque Country, and their extension back in time to overlap with the ring‐width mean developed for the Newport Ship, has allowed absolute dating and provenance of timbers used in its original construction. Further research is required to clarify the geographical source of the timbers and to develop a high‐resolution network of tree‐ring data for the region.  相似文献   

17.
ABSTRACT This paper presents a meta‐regression analysis of the empirical studies exploring the relationship between academic knowledge spillovers and regional innovation. The results of the literature are found to depend on country effects, the level of geographical aggregation employed, the method of measuring innovative output, the use of industry‐level data, and on the sectoral composition of the sample. Endogeneity, sample selection, and agglomeration forces are further elements that explain the findings on this issue but only weak evidence, after controlling for publication bias, supports the existence of a genuine spillover effect of university research on regional innovation.  相似文献   

18.
This paper reviews the role of ex ante evaluation methods in Dutch planning practice in the past decades. It is illustrated that the improvement of the evaluation methodology is to a large extent based on a learning process. Many innovations were evoked by criticism and limitations disclosed in practical applications. Since the planning environment as well as the professional skills and attitudes are also constantly changing, this demands a high degree of flexibility of the evaluation methodology. A shift of interest can be witnessed from the quality of the decision towards the quality of decision‐making. It is argued in this paper that in Dutch planning practice currently at least four different situations can be distinguished with respect to the use (or non‐use) of formal ex ante evaluation methods. In planning situations with a hierarchical power structure evaluation methods are regularly used, whereas in situations with a mixed power structure evaluation methods are only used ‘in disguise’ (e.g. hidden in geographical information systems studies, market analysis).  相似文献   

19.
Sweeping changes in national policy aim to radically transform public housing in the United States. The goal is to reduce social isolation and increase opportunities for low income tenants by demolishing ‘worst case’ housing, most of which is modern, high‐rise buildings with high vacancy and crime rates, and replacing it with ‘mixed‐income’ developments and tenant based assistance to disperse current public housing families. Transformation relies on the national government devolving more decision‐making power to local government and public housing authorities. The assumption here is that decentralizing the responsibility for public housing will yield more effective results and be more efficient. This paper explores the problematic nature of decentralization as it has been conceptualized in policy discourse, focusing on the underlying assumptions about the benefits of increasing local control in the implementation of national policy. As this paper describes, this conceived space of local control does not take into account the spatial features that have historically shaped where and how low income families live in the US, including racism and classism and a general aversion by the market to produce affordable rental units and mixed‐income developments. As a result, this conceived space of local control places the burden on low income residents to make transformation a success. To make this case, Wittgenstein's (1958) post‐structural view of language is combined with Lefebvre's view of space to provide a framework in which to examine US housing policy discourse as a ‘space producing’ activity. The Chicago Housing Authority's Plan for Transformation is used to illustrate how local efforts to transform public housing reproduce a functional space for local control that is incapable of generating many of the proposed benefits of decentralization for public housing tenants.  相似文献   

20.
Statistical regression models are presented that explain the observed variations, across urban areas, in the concentrations of two major pollutants, ozone and carbon monoxide. Model specification and estimation are based on an explicit and new spatial framework derived from the theoretical concept of well‐mixed cells, whereby the basic Fickian system of diffusion equations is integrated over the regional space partitioned into a grid of large cells. The concentration in each cell results from the balance of pollutant flows into and out of this cell and of pollutant emissions and removal within that cell, and is expressed as the sum of two concentration contributions: (1) the local effect, dependent upon pollution‐related factors around the measuring station, and (2) the regional effect, dependent upon pollutant flows originating outside the local area. A large database is developed, making extensive use of GIS technology, to spatially relate such data as pollution measurements, meteorological factors, land‐use characteristics, census socioeconomic data, and major highway network characteristics. The results confirm the appropriateness of the well‐mixed cell framework, are in line with general knowledge regarding the determinants of ozone and carbon monoxide concentrations, and clarify the role of transportation, residential fuel use, economic activities, natural environments, and meteorological factors such as temperature and solar radiation. About SO percent of the variations in concentrations are explained by these models. Several areas of further research are outlined.  相似文献   

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