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This paper investigates the substratum and infrastructure networks as relevant components of spatial planning. Since 2001, in Dutch government documents on spatial planning the Layers Approach has been presented, with three layers: substratum; networks; occupation patterns. The Layers Approach assumes that the characteristics of the substratum provide conditions for infrastructure networks and that these infrastructure networks then condition the occupation patterns, including the locations for housing, business activities and related services. These more or less hierarchical relationships are supposed to produce clear ground rules for the spatial planner. The Layers Approach seems to offer a robust methodology for spatial planning. This contribution presents the background of the Layers Approach, adds some critical notes and proposes an amendment: the Network Approach, connecting different spatial scales. After the presentation of a typology of networks a preliminary overview of the dynamics of transport networks is given. The spatial relevance of information and communication technology (ICT) networks, that support transport networks, is discussed. Nodes are presented as links between infrastructure networks and occupation patterns. The paper concludes that actors, dealing with regional spatial plans in a decentralized planning system, have to acquire an in-depth knowledge of the technology, economy and governance of current networks and the qualities of the substratum, which form a conditioning and stimulating framework for the spatial planning of urban and regional areas.  相似文献   

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Spatial spillover effects are widely studied in the literature, as an important source of externality and therefore of discrepancy between private and social optimum, creating the emergence for ad-hoc policy interventions. Within the literature, their spatially-bounded nature is highly emphasised, but the mechanisms for their spatial diffusion are generally considered as a black box, with no reference to territorialized channels through which these externalities spread around. The study aims to present a literature review on the spatial spillover concept, emphasising two main stages of reflection, the so-called spatial approach and the functional approach. This work identifies in a third approach, the cognitive approach, a new perspective to the interpretation of spatial spillovers and their conditions, and on this approach it elaborates theoretically and empirically. The main assumption is that the capabilities of economic agents to absorb and utilize spillovers—implicitly assumed by the spatial spillover theory to be invariant with respect to space—in reality highly depend on strongly territorialized and un-imitable assets, such as local trust, sense of belonging and creativity. This assumption is tested empirically on all NUTS 2 of the 27 European member countries, thanks to a regional forecasting growth model developed by the author, called MASST.  相似文献   

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A Network Approach to Commuting   总被引:1,自引:0,他引:1  
In this paper we present a model for commuting in a network of towns. A basic assumption is that all individuals have a given residential location and that every node in the network has a fixed number of jobs. We then propose a general model for the commuting of labor between the nodes in the network.  相似文献   

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A Surface-Based Approach to Measuring Spatial Segregation   总被引:8,自引:0,他引:8  
Quantitative indices of residential segregation have been with us for half a century, but suffer significant limitations. While useful for comparison among regions, summary indices fail to reveal spatial aspects of segregation. Such measures generally consider only the population mix within zones, not between them. Zone boundaries are treated as impenetrable barriers to interaction between population subgroups, so that measurement of segregation is constrained by the zoning system, which bears no necessary relation to interaction among population subgroups. A segregation measurement approach less constrained by the chosen zoning system, which enables visualization of segregation levels at the local scale and accounts for the spatial dimension of segregation, is required. We propose a kernel density estimation approach to model spatial aspects of segregation. This provides an explicitly geographical framework for modeling and visualizing local spatial segregation. The density estimation approach lends itself to development of an index of spatial segregation with the advantage of functional compatibility with the most widely used index of segregation (the dissimilarity index D ). We provide a short review of the literature on measuring segregation, briefly describe the kernel density estimation method, and illustrate how the method can be used for measuring segregation. Examples using a simulated landscape and two empirical cases in Washington, DC and Philadelphia, PA are presented.  相似文献   

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The relevance of evolutionary dynamics theories for investigating the development of sociotechnical systems has recently been recognized. In this framework the logistic growth model is considered by many scientists as an extremely appropriate framework that is able to interpret the dynamics of innovation diffusion. Starting from recent results in the literature on technological dynamics, the present paper focuses on backgrounds leading to different shapes of the conventional logistic function. By embedding these motives in the socio-attitudinal context of the system at hand, the present paper tries to give a new interpretation for the rapid/slow “take off” and dynamics of a given innovation in a spatial setting. In particular, a nested logistic dynamic model is developed here, with particular emphasis on the dynamic growth rate of the logistic function expressing—by means of an accessibility cost function—the preference intensity concerning a given innovation for a certain region/country. Finally, various simulation experiments are carried out for the case of both a two-dimensional and a four-dimensional network. The possibility of both stable and unstable diffusion patterns, depending on the parameter values in the nested “attitudinal” dynamic function, is also investigated.  相似文献   

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考古学中的网络分析以节点和链接为底层架构,强调以联系的视角去看待事物本身及其发展过程,探究此种联系是如何对古代社会的进程产生影响的.两个学术传统的交织塑造了当前网络分析在考古学中的面貌:社会网络分析(Social network analysis)和复杂性科学(Complexity science).其研究思路分为两种...  相似文献   

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This paper applies spatial duration models to the analysis of cosponsorship coalitions in the U.S. House of Representatives. This approach provides a unique and simultaneous statistical analysis of ideological space (specifically, coalition formation) and geographical space. Typically, duration models are associated with temporal longitudinal data, but recently have been adapted to the spatial domain (Pellegrini and Reader 1996). In this paper, spatial duration models are further adapted to examine ideological space including a consideration of unobserved sources of spatial variation (or omitted variable bias). We examine two features of cosponsorship coalitions, breadth and clustering. Breadth is defined as the ideological distance between the two most extreme members of the coalition which is an important “signal” to the rest of Congress regarding the scope and broad appeal of the proposed legislation. In contrast, clustering refers to the distance between individual members of a coalition and reveals the tendency, or not, of ideologically similar members of Congress to support various bills. To examine breadth and clustering, we employ spatial duration models of cosponsorship that permit a multivariate analysis incorporating both the characteristics of members of Congress and the geographical regions they represent. Results indicate that cosponsorship coalition patterns are primarily determined by the content of the legislation, not the actions of the coalition leadership. While the leadership characteristics of sponsors have a limited effect on cosponsorship breadth, the size of the coalition is the primary determinent. Leadership characteristics also have little effect on cosponsorship clustering. Rather, clustering is due to members' policy preferences, as measured by distance to the coalition leader. In addition, the duration analysis results suggest that geographical proximity between members of Congress “overcomes” ideological distance. Finally, the spatial duration approach is noted as a fruitful methodology for examining explicitly spatial patterns in both ideological or geographical space.  相似文献   

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SANET: A Toolbox for Spatial Analysis on a Network   总被引:7,自引:0,他引:7  
This article shows a geographical information systems (GIS)-based toolbox for analyzing spatial phenomena that occur on a network (e.g., traffic accidents) or almost along a network (e.g., fast-food stores in a downtown). The toolbox contains 13 tools: random point generation on a network, the Voronoi diagram, the K -function and cross K -function methods, the unconditional and conditional nearest-neighbor distance methods, the Hull model, and preprocessing tools. The article also shows a few actual analyses carried out with these tools.  相似文献   

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While research has tackled the hub-and-spoke network design problem, that research has overlooked the air-truck modal integration issue which is a common feature of real express delivery systems. This paper devises integer linear programs to represent the mode and route assignment aspects of the operational problem. The model is solved under four different levels of delivery schedule, and the results show that as the promised delivery schedule is relaxed, not only does the use of truck routes become more desirable, but also interesting adjustments in mode and hub assignment occur. Consider the case of hubs in Los Angeles and Dayton. As the time constraints are relaxed, cities such as Minneapolis and New Orleans originally linked by air to Los Angeles, switch to Dayton because cheaper truck routes become feasible.  相似文献   

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A Structural Equation Approach to Models with Spatial Dependence   总被引:2,自引:0,他引:2  
We introduce the class of structural equation models (SEMs) and corresponding estimation procedures into a spatial dependence framework. SEM allows both latent and observed variables within one and the same (causal) model. Compared with models with observed variables only, this feature makes it possible to obtain a closer correspondence between theory and empirics, to explicitly account for measurement errors, and to reduce multicollinearity. We extend the standard SEM maximum likelihood estimator to allow for spatial dependence and propose easily accessible SEM software like LISREL 8 and Mx. We present an illustration based on Anselin's Columbus, OH, crime data set. Furthermore, we combine the spatial lag model with the latent multiple-indicators–multiple-causes model and discuss estimation of this latent spatial lag model. We present an illustration based on the Anselin crime data set again.  相似文献   

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The literature contains many definitions of the rural-urban fringe, but it is difficult to find consensus on how many zones it contains, or how they can be mapped. It is argued in this paper that transitions within the fringe and at its borders are continuous rather than abrupt. In a study area adjoining London, Ontario, cluster analysis is used, and it leads to the identification of three norms. Membership probabilities are then mapped on the basis of each areal unit's resemblance to these norms through discriminant analysis.
Dans la litterature, il y a beaucoup de definitions de la fringe péri-urbaine, mais on discute le numéro de zones dans la fringe et la méthode de sa cartographie. On raisonne ici que les transitions dans la fringe et sur ses bords sont continues plutôt qu'abruptes. Dans cette étude des environs de London, Ontario, on emploie de 'cluster analysis' qui donne l'identification de trois groupes normatifs. On en fait une carte des probabilités d'adhésion sur la base du correspondance de chaque unité aréale à ces groupes normatifs par l'analyse discriminatoire.  相似文献   

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The derivation of the gravity model from utility theory is reformulated and generalized in order to show (1) how both the number of trips to individual destinations and the total travel budget may be determined simultaneously, and (2) how the effect of both distance and destination quality on trip distribution and total budget may be analyzed. Results are compared with the revealed space preference approach and are found to be superior in dealing theoretically with trip frequency and the effects of spatial context. For empirical applications, however, the revealed preference approach is advantageous.  相似文献   

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This article establishes a unified randomization significance testing framework upon which various local measures of spatial association are commonly predicated. The generalized randomization approach presented is composed of two testing procedures, the extended Mantel test and the generalized vector randomization test. These two procedures employ different randomization assumptions, namely total and conditional randomization, according to the way in which they incorporate local measures. By properly specifying necessary matrices and vectors for a particular local measure of spatial association under a particular randomization assumption, the generalized randomization approach as a whole yields a reliable set of equations for expected values and variances, which then is confirmed by a Monte Carlo simulation utilizing random permutations.  相似文献   

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A programming approach is presented for identifying the form of the weights matrix W which either minimizes or maximizes the value of Moran's spatial autocorrelation statistic for a specified vector of data values. Both nonlinear and linear programming solutions are presented. The former are necessary when the sum of the links in W is unspecified while the latter can be used if this sum is fixed. The approach is illustrated using data examined in previous studies for two variables measured for the counties of Eire. While programming solutions involving different sets of constraints are derived, all yield solutions in which the number of nonzero elements in W is considerably smaller than that in W defined using the contiguity relationships between the counties. In graph theory terms, all of the Ws derived define multicomponent graphs. Other characteristics of the derived Ws are also presented.  相似文献   

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关青兰 《攀登》2010,29(4):122-124
中共青海省委十一届六次全体会议提出的跨越发展、绿色发展、和谐发展和统筹发展是具有青海特点的科学发展模式。新闻宣传在实现四个发展中担负着重要责任。文章通过新闻宣传与“四个发展”关系的论述,阐明新闻媒体及其工作者要准确把握和理解“四个发展”的深刻内涵、基本特征和内在联系,把四个发展的要求贯穿到宣传报道之中,在建设富裕文明、和谐的新青海中做好舆论引导,为推动“四个发展”发挥应有的作用。  相似文献   

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This article analyses the evolution of the built environment in Israel's 'mixed cities' in Israel; sites shaped by the logic of ethno–nationalism, and characterized by patterns of segregation between the Jewish dominant majority and the Arab subordinate minority. The paper investigates the changes and dynamics of the urban landscape from the British Mandate period to recent times, focusing on the interrelations between ideology and architecture in its wider sense, i.e. referring to the practices of urban design and planning. The production of urban landscapes in Israeli 'mixed cities', I will argue, is a result of the social construction of an ethnic logic, and thus cannot be seen as autonomous from the existing socio–political context. Rather, I would propose, the architecture of the 'mixed city' reflects on one hand, and shapes on the other the struggle over identity, memory and belonging, rooted in urban colonialism discourse.
Empirically, this paper focuses on the city of Lod/Lydda where as in other previously Palestinian cities, a strategy of colonization had been implemented, forming the city's central planning policy since the Mandate period. The paper analyzes in detail various aspects and sites of this process, and explores the role of planners and architects in the construction of a sense of place in tangible as well as discursive levels, which are often neglected in the body of knowledge that deals with urban–ethnic conflicts.  相似文献   

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