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1.
Existing urban boundaries are usually defined by government agencies for administrative, economic, and political purposes. However, it is not clear whether the boundaries truly reflect human interactions with urban space in intra- and interregional activities. Defining urban boundaries that consider socioeconomic relationships and citizen commute patterns is important for many aspects of urban and regional planning. In this paper, we describe a method to delineate urban boundaries based upon human interactions with physical space inferred from social media. Specifically, we depicted the urban boundaries of Great Britain using a mobility network of Twitter user spatial interactions, which was inferred from over 69 million geo-located tweets. We define the non-administrative anthropographic boundaries in a hierarchical fashion based on different physical movement ranges of users derived from the collective mobility patterns of Twitter users in Great Britain. The results of strongly connected urban regions in the form of communities in the network space yield geographically cohesive, nonoverlapping urban areas, which provide a clear delineation of the non-administrative anthropographic urban boundaries of Great Britain. The method was applied to both national (Great Britain) and municipal scales (the London metropolis). While our results corresponded well with the administrative boundaries, many unexpected and interesting boundaries were identified. Importantly, as the depicted urban boundaries exhibited a strong instance of spatial proximity, we employed a gravity model to understand the distance decay effects in shaping the delineated urban boundaries. The model explains how geographical distances found in the mobility patterns affect the interaction intensity among different non-administrative anthropographic urban areas, which provides new insights into human spatial interactions with urban space.  相似文献   

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3.
对广东现有143条政区名称按照政区地名、命名规律、名称出现最早时间和距今(截至2007-12-31)时限等属性建立广东省政区地名数据库,并进行分类统计分析.研究结果表明:全省143条政区名称中,有一半政区地名在明代及明代以前就已产生.改革开放以来,出现大量以“市”和“区”为通名的新政区地名,但专名多保留不变.在空间分布...  相似文献   

4.
中国县级以上行政边界的特征及其变动趋势   总被引:1,自引:1,他引:0  
赵彪  王开泳  王甫园  刘海猛 《地理研究》2021,40(9):2494-2507
行政边界是行政区划的基本要素之一,是国家依法实施有效行政管理的空间基础和重要依据。本研究采用空间分析、基于格网的多元回归分析等方法,对中国县级以上行政边界的特征及其变动趋势进行了研究。结果表明:当前中国仍基本遵循着山川形便与犬牙相入的政区划界原则,总体呈现出行政级别越高,受山川形便的影响越明显,海拔越低,受犬牙相入的影响越明显的基本特征;现有划界方式容易造成生态分割,引发边界争议,行政管理成本较高等问题,不利于区域经济协调发展;山川河流对全国经济社会发展的影响正在减弱,经济社会发展正在逐渐突破行政边界的限制。在未来行政区划调整的过程中,应适时采取跨山跨河的方式设置行政边界,改变犬牙相入的政区设置方式,更加尊重生态环境的完整性和经济社会发展的实际需求。  相似文献   

5.
提出基于夜间灯光遥感影像、电子地图兴趣点和社会经济统计数据等,以经济地理学中的“点-轴”理论为基础,以“点-轴集聚区”的识别为核心,利用迭代自组织聚类、聚合分析、指标阈值筛选等方法,识别中国城市群及其空间范围的技术方法。通过该方法识别出中国14个城市群,其中8个城市群的空间范围与规划范围接近;与规划范围不一致的则表现为三种情况,分别揭示出规划中需要考虑的不同问题。研究结果表明,本文提出的方法能突破行政边界限制,科学反映城市群辐射范围,客观反映城市之间的社会经济联系强度,并基于“现状-动态”视角有利于深入发掘潜在的城市群对象。研究结果可以为城市群规划和管理提供参考。  相似文献   

6.
As revision of diatom taxonomy has become crucial to many recent palaeolimnological studies, the number of nomenclatural changes required has increased. Publication and validation of new names for diatoms is governed by a set of principles published periodically and known collectively as the International Code of Botanical Nomenclature. Creation of a computerised taxonomic database, designed to record recent nomenclatural changes, has revealed many of the names published to be invalid as they fail to comply with all requirements of the code. This paper outlines briefly the criteria needed to validly publish new or revised taxa.  相似文献   

7.
论文以南京主城区为例,运用GIS空间分析与社会记忆理论,探讨街巷地名变迁的时空格局与动因机制。研究发现:新增地名主要分布于老城区外围,消失地名主要分布于老城区内部。老城南既是现存街巷地名密度最大,也是消亡强度最大的地区。新增地名在20世纪50—80年代集聚于下关区沿江地带与明城墙内的老城区,90年代以来散布于老城区外围。民国开始政府成为命名主体,政府主导性与企业自主性不断增强。现存街巷以周边民居、祈愿祝福、异域文化和山水地物类为主要命名依据,既传承老城区的命名传统,也体现新城区的发展理念。宗教信仰、历史人物、经济活动、市政设施、自然方位类地名易随社会意识形态与城市功能空间的转变而消亡。权力与资本的介入催生大量新式地名,记忆的惯性延缓了老地名的消亡,记忆的社会建构性驱动地名的演进。  相似文献   

8.
Abstract

We present the notion of a natural tree as an efficient method for storing spatial information for quick access. A natural tree is a representation of spatial adjacency, organised to allow efficient addition of new data, access to existing data, or deletions. The nodes of a natural tree are compound elements obtained by a particular Delaunay triangulation algorithm. Improvements to that algorithm allow both the construction of the triangulation and subsequent access to neighbourhood information to be O(N log N). Applications include geographical information systems, contouring, and dynamical systems reconstruction.  相似文献   

9.
Mainstream gentrification research predominantly examines experiences and motivations of the middle-class gentrifier groups, while overlooking experiences of non-gentrifying groups including the impact of in situ local processes on gentrification itself. In this paper, I discuss gentrification, neighbourhood belonging and spatial distribution of class in Istanbul by examining patterns of belonging both of gentrifiers and non-gentrifying groups in historic neighbourhoods of the Golden Horn/Halic. I use multiple correspondence analysis (MCA), a methodology rarely used in gentrification research, to explore social and symbolic borders between these two groups. I show how gentrification leads to spatial clustering by creating exclusionary practices and eroding social cohesion, and illuminate divisions that are inscribed into the physical space of the neighbourhood.  相似文献   

10.
Studies of land-use change often require the combination of socioeconomic survey data with spatially continuous maps of land-cover change. One approach is to define maps of land ownership, assuming that all land-use change can be attributed to the owners or managers of each parcel of land. Unfortunately, records of administrative boundaries between towns and villages are commonly unavailable in developing countries and prohibitively costly or time consuming to map for individual projects. However, point locations of the settlements themselves can be obtained easily from existing maps or remotely-sensed imagery. In this paper we compare three methods – circular buffers, unweighted Voronoi polygons (sometimes referred to as Thiessen polygons) and multiplicatively weighted Voronoi polygons – for estimating boundaries between villages in an agricultural landscape in West Africa. The benefits and limitations of each approach are discussed, and their accuracy assessed using 98 independently collected GPS coordinates of village boundaries. We present a novel method for generating and optimising weights for multiplicatively weighted Voronoi polygons using survey data of village sizes from a subset of villages. By using both spatial information and survey data from villages, we show that multiplicatively weighted Voronoi polygons outperform other methods of predicting village boundaries, and increase the correlation coefficient between surveyed village area and mapped areas from 0.18 to 0.68 compared with more commonly used unweighted Voronoi polygons. Our method of weighting Voronoi polygons can be implemented with data and software commonly available to researchers and non-governmental organisations.  相似文献   

11.
Large-scale urban redevelopment has caused the breakdown of traditional social bonds in Chinese cities. To date, very few studies have attempted to delve into the impact of this urban redevelopment on neighbourhood cohesion. Using data collected from questionnaires conducted in 20 urban villages and 1 urban village redevelopment neighbourhood in Guangzhou, this paper examines the impact of urban village redevelopment on the restructuring of neighbourhood attachment, neighbourly interaction, and community participation—three dimensions of neighbourhood cohesion. Results of a path analysis show that, overall, neighbourhood cohesion declines after redevelopment occurs, and that the sources of neighbourhood cohesion differ between urban villages and the redevelopment neighbourhood. Our findings show that after redevelopment, neighbourhood attachment becomes more influenced by residential satisfaction but less by neighbourly contacts, and community participation becomes less subject to neighbourly interaction and neighbourhood attachment. Such changes occur as a result of the differentiation between social groups and the concurrence of environmental restructuring and demographic reconstruction during the process of urban village redevelopment.  相似文献   

12.
ABSTRACT

The aim of the article is to explain the phenomena of mergers and territorial disintegration of Polish towns and cities from three perspectives: social, economic and spatial-primal. Administrative border changes are fundamental components of local urban policy guidelines in countries that have experienced a dual history in the socialist and post-socialist periods, such as Poland. The main method of the authors research was the application of statistical and cartographic methods focused on measuring quantitative administrative changes in urban areas and their demographic effects. The scope of the research covered all towns in Poland existing in the years 1945–2018. Since the changes in the administrative boundaries of cities particularly concern the rural areas in the vicinity of large cities, the suburban municipalities surrounding urban centres were analysed too. The findings underline the deterministic role of political systems in the territorial expansion of towns and cities, and indicates their role for current planning decisions. The authors conclude that noticeable differences between two analysed periods have had at least two significant causes. First, the political and economic systems determining the changes differed, and second, each system was accompanied by differing directions of economic development and therefore also different ‘urbogenic’ forces.  相似文献   

13.
This study examines interspecific differences in the architecture and field characteristics of the burrow systems of Brants' whistling rat, Parotomys brantsii, and Littledale's whistling rat, Parotomys littledalei. The two rodents are endemic to the arid west region of southern Africa. Both build complex burrow systems with numerous nest chambers and associated interconnecting tunnels, as well as a number of entrances. Burrow systems of P. littledalei are restricted to areas of good plant cover, whilst many P. brantsii burrows are situated in open locations with only limited plant cover. Further, the burrows of P. brantsii cover a much larger area than those of P. littledalei, with many more entrances. As P. brantsii feed predominantly within the boundaries of their burrows and not in the open veld, their burrow systems effectively serve as a predator refuge, into which this diurnal rodent can quickly run in the event of danger. Thus, by building large multi-holed burrow systems, P. brantsii have become independent of the protection offered by bush cover and can exist within relatively open areas within their distributional range. On the other hand, the reduced number of entrances to P. littledalei burrow systems may largely restrict this species to areas with adequate cover, including coastal and riverine bush, with which it is often associated.  相似文献   

14.
Current independent filmmaking in Malaysia has the potential to be an alternative and viable space for creative and political expression, relative to mainstream national cinema (Malay cinema) and to the state. I focus on alternative imagery and sociocultural mappings of Kuala Lumpur in three ‘indie’ films. All three films contain documentary elements capturing social geographies of the city not represented in mainstream Malay cinema, or even if represented not subjected to a critical gaze by the filmmaker. The Big Durian centres on the perspectives of the city's urban middle class of all ethnicities; Bukak Api portrays the daily struggles of Malay transsexual sex workers in Chow Kit, a predominantly working‐class Chinese neighbourhood and red light district; and 18? highlights the opinions of the nongovernmental organization community, bohemians, artists, anarchists and media activists mostly in the cosmopolitan suburb of Bangsar. These representations of the Malaysian urban landscape are pretexts for and politicize the national landscape through a discussion of ethnicity and race politics, sexuality, and the lack of space for freedom of creative expression and critical thinking.  相似文献   

15.
土壤区划类型的参比与属地化研究   总被引:2,自引:2,他引:0  
文章以详细的1981年土壤分区资料为基础,将以发生分类(GSCC)为基础的土壤类型名称分别参比成中国土壤系统分类(CST)名称和美国土壤系统分类(ST)名称。同时利用G IS空间分析技术,确定了中国8个土壤大区在地级市(盟)和各县、区、旗(市)的行政归属,并以江南低山丘陵和台湾北部地区为例,探讨了二级分区的行政归属。  相似文献   

16.
Urban hierarchies are closely related to economic growth, urban planning and sustainable urban development. Due to the limited availability of reliable statistical data at fine scales, most existing studies on urban hierarchy characterization failed to capture the detailed urban spatial structure information. Previous studies have demonstrated that night time light data are correlated with many urban socio-economic indicators and hence can be used to characterize urban hierarchies. This paper presents a novel method for studying urban hierarchies from night time light data. Night time light data were first conceptualized as continuous mathematical surfaces, termed night time light surfaces. From the morphology of these surfaces the corresponding surface networks were derived. Hereafter, a night time light intensity (NTLI) graph was defined to describe the morphology of the surface network. Then, structural similarity between the night time light surfaces of any two different cities was calculated via a threshold-based maximum common induced graph searching algorithm. Finally, urban hierarchies were defined on the basis of the structural similarities between different cities. Using the 2015 annual NPP-VIIRS night time light data, the urban hierarchies of 32 major cities in China were successfully examined. The results are highly consistent with the reference urban hierarchies.  相似文献   

17.
《Urban geography》2013,34(7):601-626
The commemoration of slain civil rights leader Martin Luther King Jr. (MLK) is a growing movement in many American cities and towns. School naming is an important yet underanalyzed part of this project. A recent struggle in Riverside, California over naming a high school for MLK is used as a springboard for: (1) conceptualizing school names as cultural arenas for debating student and community identity and (2) conducting a general study of the types of U.S. public schools named for King. As illustrated in California, school naming can be interpreted by one social group as a means of integrating and inspiring students historically and viewed by another group as a means of drawing boundaries around students in terms of race and local heritage. According to 1997-1998 data, 110 public schools bear King's name. They are located most often in the central cities of large and mid-size urban areas. King's name is most frequently found on schools that teach early and middle grades. Schools named for Martin Luther King do not necessarily denote a "Black" school in terms of the racial characteristics of students, although they do not fully integrate Whites with African Americans or Whites with minorities in general. Naming schools for King is part of a larger refashioning of the urban cultural landscape as racial and ethnic groups increasingly seek public recognition of their historical achievements.  相似文献   

18.
As examinations of the rural–urban interface move beyond a focus on the rural or urban fringe as a location and move toward examining the patterns and processes that both divide and link rural and urban places, a broader (re)conceptualization of the rural–urban interface becomes increasingly important. Thus far the question of boundaries and interfaces between so-called urban and rural locales has mostly revolved around where and when such boundaries occur (including significant coverage of the differences and conflicts between urban vs. rural people), rather than asking what physical or social functions are being served by the rural–urban interface itself. In response, I (re)frame the rural–urban interface not only as a boundary between two distinct spaces but also as a conduit, a place of exchange, and a flux point between them. Using a particular case of contested ecologies in the exurban Sierra Nevada foothills of California, I (re)conceptualize the rural–urban interface as meaning, model, and metaphor (MMM), situating contrasting people and places in an ongoing negotiation of place and environmental meaning along the (ex)urbanizing edge. Although the differences between rural and urban are increasingly unclear, the division continues to be compelling from environmental and sociopolitical standpoints. I argue that (perceived) boundaries are instrumental in understanding physical–material change and for mitigating social conflicts occurring across them. As such, attention to the patterns, processes, and flows that connect or separate rural and urban areas is critical to forging effective and long-lasting solutions to contemporary social, economic, and environmental problems.  相似文献   

19.
ABSTRACT

An increasing number of social media users are becoming used to disseminate activities through geotagged posts. The massive available geotagged posts enable collections of users’ footprints over time and offer effective opportunities for mobility prediction. Using geotagged posts for spatio-temporal prediction of future location, however, is challenging. Previous studies either focus on next-place prediction or rely on dense data sources such as GPS data. Introduced in this article is a novel method for future location prediction of individuals based on geotagged social media data. This method employs the hierarchical density-based clustering algorithm with adaptive parameter selection to identify the regions frequently visited by a social media user. A multi-feature weighted Bayesian model is then developed to forecast users’ spatio-temporal locations by combining multiple factors affecting human mobility patterns. Further, an updating strategy is designed to efficiently adjust, over time, the proposed model to the dynamics in users’ mobility patterns. Based on two real-life datasets, the proposed approach outperforms a state-of-the-art method in prediction accuracy by up to 5.34% and 3.30%. Tests show prediction reliability is high with quality predictions, but low in the identification of erroneous locations.  相似文献   

20.
This paper reports on an attempt to combine neo-classical urban economic theory with complex systems methods. The innovative feature of our model from the point of view of conventional economic theory lies in its explicit treatment of spatial relationships and time sequence. From the perspective of raster or cellular GIS models of urban processes, the work is innovative in that it replaces the more usual heuristic cell-transition rules with micro-economic theory. The mix of modelling paradigms is not unproblematic, however, and we discuss the challenges encountered at this research frontier. These notwithstanding, our hybrid model has the potential to be used as a GIS-based laboratory for exploring micro-economic propositions, particularly those relating to urban processes that are path dependent. The version of the model reported simulates spatially equilibriated path dependent futures of a city governed by local development decisions that are at partial equilibria in the neo-classical sense. Two simulations are described which permit visual and economic exploration of (a) an explicitly spatial version of the economic theory of externalities and (b) a new theory of densification. The dual paradigm (Cellular Automata-neo-classical economics) leads to an interesting class of simulations in terms of stability. Economically our simulated cities become increasingly efficient, in terms of private and social product. The long-run economic equilibrium is achieved by many individually efficient negotiations based only on local information. There is no parallel long-run spatial equilibrium however. The spatial configuration of land uses is constantly shifting as a result of randomness in the land use bidding process. The spatial instability is, however, limited by the self-organised drive for greater overall economic efficiency. In economic terms, the model's spatial instability represents random re-allocation of land-use within a set of Pareto-efficient spatial configurations - an intriguing result that we intend to follow up in future work.  相似文献   

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