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1.
We designed a geographical model for simulating the distribution of urban growth in systems of cities. The model incorporates the hierarchical and spatial diffusion of innovation cycles through gravitational interactions within a set of cities. Using theoretical simulations, we demonstrate that this model is able to reproduce the observed properties of urban systems for the log‐normal distribution of city sizes as well as the observed distribution of growth rates. Our experimentation was performed on a large harmonized historical database that includes a few hundred French urban agglomerations between 1831 and 1999 (Pumain‐INED database). Both spatial interaction and innovation cycles are necessary ingredients to explain the evolution of urban hierarchies. We suggest that Gibrat's generic stochastic growth model based on independent entities should be replaced by a more relevant model of spatially and temporally interdependent geographical entities.  相似文献   

2.
This article presents a new metric we label the colocation quotient (CLQ), a measurement designed to quantify (potentially asymmetrical) spatial association between categories of a population that may itself exhibit spatial autocorrelation. We begin by explaining why most metrics of categorical spatial association are inadequate for many common situations. Our focus is on where a single categorical data variable is measured at point locations that constitute a population of interest. We then develop our new metric, the CLQ, as a point‐based association metric most similar to the cross‐k‐function and join count statistic. However, it differs from the former in that it is based on distance ranks rather than on raw distances and differs from the latter in that it is asymmetric. After introducing the statistical calculation and underlying rationale, a random labeling technique is described to test for significance. The new metric is applied to economic and ecological point data to demonstrate its broad utility. The method expands upon explanatory powers present in current point‐based colocation statistics.  相似文献   

3.
This article provides an empirical evaluation of a hierarchical approach to modeling commuting flows. As the gravity family of spatial interaction models represents a benchmark for empirical evaluation, we begin by reviewing basic aspects of these models. The hierarchical modeling framework is the same that Thorsen, Ubøe, and Nævdal (1999) used. However, because some modifications are required to construct a more workable model, we undertake a relatively detailed presentation of the model, rather than merely referring to the presentation in Thorsen, Ubøe, and Nævdal (1999) . The model uses a hierarchical specification of a transportation network and the individual search procedure. Journeys to work are determined by the effects of distance deterrence and of intervening opportunities, and by the location of potential destinations relative to alternatives at subsequent levels in a transportation network. The model calibration uses commuting data from a region in western Norway. The estimated parameter values are reasonable, and the explanatory power is very satisfactory when compared with the results of a competing destinations approach.  相似文献   

4.
The Schelling model describing segregation between two groups of residential agents, reflects the most abstract, basic view of noneconomic forces motivating residential migrations: be close to people of “your own” kind. The model assumes that residential agents, located in neighborhoods where the fraction of “friends” is less than a predefined threshold value F, try to relocate to neighborhoods where this fraction is F or higher. For groups of equal size, Schelling's residential pattern converges either to complete integration (random pattern) or segregation, depending on F. We investigate Schelling model pattern dynamics as a function of F in addition to two other parameters—the ratio of groups' numbers, and neighborhood size. We demonstrate that the traditional integration–segregation pattern dichotomy should be extended. In the case of groups of different sizes, a wide interval of F‐values exists that entails a third persistent residential pattern, one in which a portion of the majority population segregates while the rest remains integrated with the minority. We also demonstrate that Schelling model dynamics essentially depend on the formalization of urban agents' residential behavior. To obtain realistic results, the agents should be satisficers, and the fraction of the agents relocating irrespective of the neighborhood's state should be nonzero. We discuss the relationship between our results and real‐world residential dynamics.  相似文献   

5.
This paper analyses the effect of location characteristics on urban growth using regression cubic splines. Our empirical analysis shows that in Spain, differences in accessibility to major urban centres and geographic isolation help explain differences in population growth rates across municipalities between 2001 and 2014. Moreover, even though physical proximity to large cities is usually assumed to be closely related to the attractiveness of a municipality, we found that urban population growth is even more related to the joint effect of distance to major centres and agglomeration. In this respect, there seems to be a threshold from which agglomeration diseconomies come into play such that a greater proximity to major cities and/or being localized within a more densely populated area goes against local growth.  相似文献   

6.
Abstract

The physical growth of cities is usually used to define the main direction of a city's development. This definition is key to understanding the city's current state and to plan for the future. Many urban planners agree that master plans should include historical urban growth and aim to specify the effective factors driving urban growth. However, defining urban boundaries and historical urban areas is a difficult task. The lack of satellite images, air photos, and real maps to use as base maps for historical urban studies is a problem that a researcher may face when determining patterns of urban development or conducting other analyses. In this article, the authors examine historical changes of the urban boundaries of the Ottoman city of Manisa. They analyze the physical growth of this large city by using the historical buildings (mosques, masjids, madrasas, baths, caravansary, and others) as markers.  相似文献   

7.
A tale of two cities: 9 Comparative analysis of urban conflicts of Montreal and Valencia, 1995–2010 Metropolization processes at work in contemporary societies produce social and spatial change, which can raise strong opposition from a variety of urban actors, leading to acts of dissent. While such urban conflict has been examined in the past, geographical analysis of urban conflicts as sociospatial processes is more recent. Systematic quantitative research on urban conflict is virtually nonexistent in terms of comparative analysis conducted with an international perspective. Systematic comparative analysis sheds light on the existing relationship between urban conflicts and the socio‐territorial contexts in which conflicts emerge and evolve. This article presents a comparative analysis of urban conflict that occurred in a selection of boroughs in two cities characterized by different geographical realities, Valencia (Spain) and Montreal (Canada), between 1995 and 2010. Spatial autocorrelation techniques applied to a conflict database show a significant relationship between the emergence of urban conflict and the spatial distribution of some contextual variables. Indeed, for Montreal as for Valencia, the concentration of urban conflict is the greatest in the most deprived neighbourhoods. Also, regarding the management and regulation of urban conflict, results shed light on important differences between Montreal and Valencia. These differences include the outcome of urban conflicts, repertoire of action of actors involved in conflict activity, and the type of contestation faced by actors who promote the challenged urban projects.  相似文献   

8.
This study proposes a theory‐based cellular automata (CA) in which CA rules are constructed on the basis of a theory of urban land‐use change and other local conditions. Rent gap theory that describes urban redevelopment and exogenous conditions that reflect urban development are embedded into a CA to simulate changes of land use. The theoretical framework provides a strong conceptual background for the CA simulation. A case study demonstrates the flexibility of the integrated framework for simulating land‐use changes in complex settings. This research aims to help decision‐makers formulate appropriate development plans.  相似文献   

9.
Bench Ansfield 《对极》2018,50(5):1166-1185
The term inner city first achieved consistent usage through the writings of liberal Protestants in the USA after World War II. Its genesis was the product of an era when a largely suburban mainline Protestantism was negotiating its relationship to American cities. Liberal Protestants’ missionary brand of urban renewal refocused attention away from the blight and structural obsolescence thought to be responsible for urban decay, and instead brought into focus the cultural pathologies they mapped onto black neighbourhoods. The term inner city arose in this context, providing a rhetorical and ideological tool for articulating the role of the church in the nationwide project of urban renewal. I argue that even as it arose in contexts aiming to entice mainline Protestantism back into the cities it had fled, the term accrued its meaning by generating symbolic and geographic distance between white liberal churches and the black communities they sought to help.  相似文献   

10.
陶伟  何新  蒋伟 《人文地理》2014,29(5):40-48
堪舆是中国独特的城市形态理论。作为聚落当中最持久、最稳定的形态要素,则为城市形态研究提供了一个可阅读的文本。本文以平遥古城为案例地,以堪舆文化为视角,通过田野调查、访谈与形态要素分析,对传统民居的形态变迁进行了详细考察和论证,总结了平遥古城传统民居的形态特征及其演化的三种类型,深入探讨了引起形态演变的原因。本工作不仅对基于西方城市形态理论的已有研究形成了有益互补,而且对平遥古城历史延续和文脉保护具有现实意义。  相似文献   

11.
Metropolization and the rank/size ’law‘: the Canadian case, 1971–2001 There is currently considerable interest in the process of metropolization. One of the consequences of this process, observed by numerous researchers, is the slower growth and even decline of small and medium cities. From a theoretical point of view, this process is compatible with endogenous growth theory: metropolitan areas offer economic actors certain key factors (access to information, to global networks, etc.) that smaller cities cannot. Concurrently, however, there is a resurgence of interest in Zipf's law and, more generally, in the stability of urban hierarchies. These two bodies of work appear to be in contradiction. However, using Canadian data from 1971 to 2001, we show that whilst metropolization is indeed occurring, this is not necessarily incompatible with a regular urban hierarchy. Indeed, if it is assumed that Zipf's rank‐size rule applies to urban systems in stable socio‐economic contexts, and that this regularity can be disrupted by fundamental social and economic changes, then the current wave of metropolization can be interpreted as a re‐ordering of cities in the face of the major social and economic changes of the 1980s and 1990s, which may eventually lead to a new equilibrium compatible with Zipf's law.  相似文献   

12.
Residents of city and suburban neighbourhoods have diverged in the way they vote, with inner-city dwellers preferring political parties on the left while suburbanites increasingly vote for parties on the right. Yet it is not clear whether such a division is more evident between residents of central and suburban municipalities (the jurisdictional hypothesis), or between residents of neighbourhoods differentiated by urban form and, by assumption, lifestyle (the morphological hypothesis). While there are clear reasons for the predominant reliance on municipal differences in research based in the U.S. and other countries, it is not evident that these reasons apply in the Canadian context. This article examines how urban boundaries articulate electoral differences between metropolitan residents in Canada's three largest urban regions, using aggregate election data for federal elections between 1945 and 2000, survey data from the 2000 Canada election study and a series of indices developed by the author. It is found that while trends towards city–suburban polarization are similar regardless of the boundaries used to define the zones, in the Canadian case the results are stronger and more significant when boundaries based on urban form (between pre-and post-war development) are employed. The implications of these results for the relationship between urban space and political values in Canadian cities are then discussed.  相似文献   

13.
The Periplus of the Erythraean Sea describes the route of a trade ship in the ancient Erythraean Sea following certain reference points. One of these was called τ? π?ρα? τ?? ?νακομιδ??, from which the distance to Ptolemais of the Hunts was given. It was generally understood as the ‘endpoint of return’ and thought to be Berenice. In fact, the phrase is to be understood as ‘the endpoint of sailing/delivery from (Egypt)’ and the place appears to be identifiable with modern Anfile Bay, where the trade ships turned back. The port itself had to be visited on the way back to Egypt. The reason was connected with the primary goal of the establishment of the port: it was much more practical to take elephants aboard on the way back to Egypt. The information on Ptolemais of the Hunts seems to derive from a late Ptolemaic source. The exact route of the ship, referred to by the author of the Periplus, is unknown and even knowledge of the exact distance from the reference point does not allow us to identify a region, where Ptolemais of the Hunts is to be sought.  相似文献   

14.
Biogeographical studies are often based on a statistical analysis of data sampled in a spatial context. However, in many cases standard analyses such as regression models violate the assumption of independently and identically distributed errors. In this article, we show that the theory of wavelets provides a method to remove autocorrelation in generalized linear models (GLMs). Autocorrelation can be described by smooth wavelet coefficients at small scales. Therefore, data can be decomposed into uncorrelated and correlated parts. Using an appropriate linear transformation, we are able to extend GLMs to autocorrelated data. We illustrate our new method, called the wavelet‐revised model (WRM), by applying it to multiple regression with response variables conforming to various distributions. Results are presented for simulated data and real biogeographical data (species counts of the plant genus Utricularia [bladderworts] in grid cells throughout Germany). The results of our WRM are compared with those of GLMs and models based on generalized estimating equations. We recommend WRMs, especially as a method that allows for spatial nonstationarity. The technique developed for lattice data is applicable without any prior knowledge of the real autocorrelation structure.  相似文献   

15.
The objective of this paper is to compare fractal‐based parameters calculated by different fractal methods for urban built‐up areas and to link the observed spatial variations to variables commonly used in urban geography, urban economics, or land‐use planning. Computations are performed on Brussels, Belgium. Two fractal methods (correlation and dilation) are systematically applied for evaluating the fractal dimension of built‐up surfaces; correlation is used to evaluate the fractal dimension of the borders (lines). Analyses show that while fractal dimension is ideal for distinguishing the morphology of Brussels, each estimation technique leads to slightly different results. Interesting associations are to be found between the fractal dimensions and rent, distance, income, and planning rules. Despite its limitations, fractal analysis seems to be a promising tool for describing the morphology of the city and for simulating its genesis and planning. The model is robust: it replicates the urban spatial regularities and patterns, and could hence fruitfully be integrated into intra‐urban simulation processes.  相似文献   

16.
The spatial interaction between rural and urban areas is intense in the Global South. While research into how this interaction influences livelihood opportunities is extensive, longitudinal identification and analysis of rural people's long‐distance mobility is rudimentary. This is problematic given the possible repercussions of a greater flow of people for transport system management (congestion, emissions, investments, social exclusion, etc.). Based on longitudinal survey data from 1990 to 2008/2009, this article addresses this gap by exploring how the long‐distance mobility behaviour of households and individuals has changed over a period of intensified rural–urban interaction in a rural Philippine area. The article furthermore addresses the individuals' mobility desires and restrictions related to long‐distance travel. The results indicate that both accessibility effects and effects related to information and communication technology (ICT), concentration of activities and opportunities towards major cities, age, labour market, and economic situation. Over time, particularly since improved accessibility conditions have enabled much faster travelling, more people have come to travel more frequently (although a suppressed demand is still present and inequalities are considerable) to more distant destinations, major cities in particular, for mainly social motives. A recent countertrend is evident, partly arising from mobile phones replacing physical movement. The increase in private vehicle ownership has so far been slow, so modal choice is still highly sustainable. Overall, the findings support core ideas derived from the new economic geography, but also notes, with earlier studies in transport geography, that travel time is a prime consideration.  相似文献   

17.
A key area in the analysis of urban structural evolution is identifying discontinuities. Effective analysis could improve long‐term forecasting and provide a better understanding of how to steer an urban system toward a desirable future state. We use a simple aggregate retail model to demonstrate an algorithm for identifying discontinuities in model parameter space. Explorations of retailing in both Greater London and South Yorkshire in the United Kingdom illustrate how understanding a system's potential for discontinuity can provide insights for both policy makers and retail businesses. The Harris and Wilson model, described in the section so‐named, is used as a simple archetype to illustrate the new framework. This model can be developed in a straightforward way to incorporate further refinement. In “ Executing the model and visualizing the results ,” we describe a single model run and in “ Investigating discontinuities ,” we explain our framework for detecting and analyzing discontinuities. “ Identifying discontinuities in the London retail system ” shows the results of applying this methodology to the Greater London retail system, and in “ Practical applications ,” we explore the policy applications for this technique as related to the decline of town centers in the South Yorkshire retail system. Some concluding comments are offered in “ Conclusions .”  相似文献   

18.
The ability of people to access opportunities offered by the built environment is circumscribed by various sets of space–time constraints, including the requirements to meet other persons at particular times and places to undertake activities together. While models of space–time accessibility recognize that joint activities may constrain the performance of activities in space and time, their specifications do not explicitly acknowledge the opportunities that individuals of a group have for joint activity participation. Therefore, this article focuses on joint activity participation and argues that collective activity decisions are the outcome of a complex process involving various aspects of timing, synchronization, and social hierarchy. The utility‐theoretic model proposed here quantifies the extent to which opportunities can be jointly accessed by a particular group of people within a specific time period. Central to the approach are three key variables: the attractiveness of an opportunity, the time available for activity participation, and the travel time to an activity location. Because of the multiperson character of joint activities, the determination of these variables is subject to individual preferences, privileges, and power differentials within a group. Specific attention is given to how time‐of‐day and synchronization effects influence the opportunities accessible to a group of individuals. The impact of these factors on joint accessibility is illustrated by a real‐world example of an everyday rendezvous scenario. The outcomes of a simulation exercise suggest that time‐of‐day and synchronization effects significantly affect the benefits that can be gained from opportunities for joint activities.  相似文献   

19.
This article reports about a metaregression analysis of empirical results generated using data for the northern Netherlands (1988–2002) in order to investigate the ambiguity in results in the population–employment interaction literature. Specifically, the analysis deals with the issue whether “jobs follow people” or “people follow jobs.” The article starts with introducing the basics of quasi‐experimental meta‐analysis and with identifying some advantages of using quasi‐experimental meta‐analysis as compared with the standard meta‐analysis approach. Two subsequent sections document the selection of the population–employment interaction model and salient characteristics of the data set as well as the setup of the primary analyses. A total of 4,050 quasi‐experimental empirical results for the jobs–people direction of causality are generated using different specifications and estimators for a spatial econometric interaction model. The subsequent metaregression analysis reveals that the empirical results are largely shaped by the spatial, temporal, and employment characteristics of the data sampling. The results also appear much more sensitive to different measurements of the model's key variables when compared with alternative specifications of the spatial weights matrix. The main determinant driving empirical results about jobs–people causality are differences in model specification and estimation, as revealed by an inherent bias in parameter estimates and misguided inferences for some of the commonly used specifications. Finally, suggestions for future research are identified.  相似文献   

20.
The space–time autoregressive integrated moving average (STARIMA) model family provides useful tools for modeling space–time processes that exhibit stationarity (or near stationarity) in space and time. However, a more general method for routine use and efficient computation is needed to model the nonlinearities and nonstationarities of environmental space–time series. This article presents a hybrid framework combining machine learning and statistical methods to address this issue. It uses an artificial neural network (ANN) to extract global deterministic (nonlinear) space–time trends and a STARIMA model to extract local stochastic space–time variations in data. A four‐stage procedure is proposed for analyzing and modeling space–time series. The proposed framework and procedures are applied to forecast annual average temperature at 137 national meteorological stations in China. The results demonstrate that the hybrid framework achieves better forecasting accuracy than the STARIMA model alone. This finding suggests that the combination of machine learning and statistical methods provides a very powerful tool for analyzing and modeling space–time series of environmental data that have strong spatial nonlinear and nonstationary components.  相似文献   

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