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1.
The fundamental basis for territorial political representation is the presumption that people share greater common interests with others in closer geographic proximity than with people farther away. This principle is found in U.S. legal requirements that districts for the House of Representatives and state legislatures should not needlessly divide “communities of interest” and should be “reasonably compact.” We propose a new objective standard to evaluate spatial fairness of redistricting plans: the extent to which a delineation minimizes total distance between all pairs of people assigned to the same district. To date, the legal standard of compactness has primarily been thought of in terms of the shapes of political districts, but boundary shape may have little correspondence with how populations are actually clustered and dispersed. Inter‐person separation, by contrast, provides a direct, intuitive metric for evaluating the congruence of districting plans with the territorial basis of political representation. To operationalize an inter‐person separation standard, we propose a model and present a heuristic method for delineating comparator districting schemes. We apply the standard to the current U.S. Congressional Districts in the states of Arizona and North Carolina to demonstrate how inter‐person separation could be used to develop and vet future redistricting plans.  相似文献   

2.
The explicit consideration of the shape of geographic features has been largely ignored in existing spatial association measures. The primary contribution of this work is the development of a new local spatial association measure—a Local Indicator of Spatial and Shape Association (LISShA). The LISShA measure is modeled after local Geary's Spatial Autocorrelation measure with distance between shapes, calculated using the Small–Le metric, replacing difference between attribute values and the spatial neighborhood defined by Fréchet distance. We provide some explanation of these metrics and show, in detail, how the LISShA and proposed moments are calculated in a one‐dimensional context in a case study of maritime anomaly detection.  相似文献   

3.
The p‐compact‐regions problem involves the search for an aggregation of n atomic spatial units into p‐compact, contiguous regions. This article reports our efforts in designing a heuristic framework—MERGE (memory‐based randomized greedy and edge reassignment)—to solve this problem through phases of dealing, randomized greedy, and edge reassignment. This MERGE heuristic is able to memorize (ME of MERGE) the potential best moves toward an optimal solution at each phase of the procedure such that the search efficiency can be greatly improved. A dealing phase grows seeded regions into a viable size. A randomized greedy (RG of MERGE) approach completes the regions' growth and generates a feasible set of p‐regions. The edge‐reassigning local search (E of MERGE) fine‐tunes the results toward better objectives. In addition, a normalized moment of inertia (NMI) is introduced as the method of choice in computing the compactness of each region. We discuss in detail how MERGE works and how this new compactness measure can be seamlessly integrated into different phases of the proposed regionalization procedure. The performance of MERGE is evaluated through the use of both a small and a large p‐compact‐regions problem motivated by modeling the regional economy of Southern California. We expect this work to contribute to the regionalization theory and practice literature. Theoretically, we formulate a new model for the family of p‐compact‐regions problems. The novel NMI introduced in the model provides an accurate, robust, and efficient measure of compactness, which is a key objective for p‐compact‐regions problems. Practically, we developed the MERGE heuristic, proven to be effective and efficient in solving this nonlinear optimization problem to near optimality. El problema de regiones compactas tipo p (p‐compact regions) consiste en la búsqueda de la agregación de n unidades espaciales atómicas que produzca regiones contiguas de tipo p‐compacto. Este artículo reporta los esfuerzos de los autores en el diseño de un marco heurístico MERGE (memory‐based randomized greedy and edge‐reassignment) el cual resuelve este problema a través de las fases de la negociación (dealing), codicia aleatorizada (randomized greedy), y la reasignación de bordes (edge reassignment). El heurístico MERGE es capaz de memorizar ( ME de MERGE) los mejo)res desplazamientos posibles hacia una solución óptima en cada fase del procedimiento de tal manera que la eficiencia de la búsqueda puede ser mejorada en gran medida. La fase de negociación crea regiones “sembradas” aleatoriamente y las hace crecer en diferentes tamaños . El componente de codicia aleatorio (RG de MERGE) completa la fase de crecimiento de las regiones y genera un conjunto factible de regiones tipo p. La reasignación de bordes se realiza vía una búsqueda local (E de MERGE) que afina los resultados con el fin the alcanzar los objetivos. Además, el enfoque propuesto aquí utiliza el momento de inercia normalizado (normalized momento of inertia‐NMI) como método para el cálculo de la compacidad de cada región. El artículo discute en detalle el funcionamiento de MERGE y cómo esta nueva medida compacidad puede integrarse perfectamente en las diferentes fases del procedimiento de regionalización propuesto. Para ilustrar y evaluar el desempeño de MERGE, el metodo es aplicado a dos problemas de p‐compact regions, uno grande y uno pequeño, basados en el modelado de la economía regional del sur de California. Los autores esperan que este trabajo contribuya a la literatura teórica y práctica de la regionalización. En términos teóricos, se formula un nuevo modelo de la familia de problemas de p‐compact regions. El NMI equipa al modelo con una novedosa forma de obtener una medida exacta, robusta y eficiente de compacidad, que es un objetivo clave para los problemas región compacta tipo p. En términos prácticos, se desarrolla MERGE, un procedimiento heurístico que ha demostrado ser eficaz y eficiente en la solución de este problema de optimización no lineal de manera casi óptima. p紧凑区域问题包含寻找一种聚集方法,将n个不可分割的空间单元集合成p紧凑的邻近区域。本文阐述了一种启发式架构MERGE(基于记忆的随机贪婪和边界再赋值算法),通过处理、随机贪婪和边界再分配这几个阶段解决p紧凑问题。MERGE启发式框架能存储 处理过程每个阶段中,向一个最优解的潜在最佳移动方式,从而可极大地提升搜索效率。一个处理阶段可将种子区域生长到可行大小。而一个随机贪婪阶段能完成区域增长并生成p区域的可行集。在边界再分配的局部搜索阶段对结果进行微调以达到更好的目标。此外,引入标准化的惯性矩作为每个区域紧凑度计算的选择方法。本文详细讨论了MERGE的工作原理,以及这种新的紧凑度测算方法如何能无缝地整合到所提出的区域化流程的不同阶段。通过在南部加州区域经济建模中一小一大两个p紧凑区域问题的应用,对MERGE的性能进行评估,期望该工作能够对区域化理论和实践作出贡献。理论上,提出了可解决p紧凑区域这类问题的新模型。在模型中引入新颖的标准化惯性矩这一精确的、鲁棒的和有效的紧凑度度量方法,是解决p紧凑区域问题的关键目标;实践上,本文发展了MERGE启发式框架,并证明了它在解决这种非线性优化问题近优性的有效性和高效性。  相似文献   

4.
Location‐based social media make it possible to understand social and geographic aspects of human activities. However, previous studies have mostly examined these two aspects separately without looking at how they are linked. The study aims to connect two aspects by investigating whether there is any correlation between social connections and users' check‐in locations from a socio‐geographic perspective. We constructed three types of networks: a people–people network, a location–location network, and a city–city network from former location‐based social media Brightkite and Gowalla in the U.S., based on users' check‐in locations and their friendships. We adopted some complexity science methods such as power‐law detection and head/tail breaks classification method for analysis and visualization. Head/tail breaks recursively partitions data into a few large things in the head and many small things in the tail. By analyzing check‐in locations, we found that users' check‐in patterns are heterogeneous at both the individual and collective levels. We also discovered that users' first or most frequent check‐in locations can be the representatives of users' spatial information. The constructed networks based on these locations are very heterogeneous, as indicated by the high ht‐index. Most importantly, the node degree of the networks correlates highly with the population at locations (mostly with R2 being 0.7) or cities (above 0.9). This correlation indicates that the geographic distributions of the social media users relate highly to their online social connections.  相似文献   

5.
Films carry an original geographic discourse. Beyond the vision of an author, they often reflect a society's perspective on territories. The goal of this research is to study the geographic discourse developed by Canadian cinema through an analysis of the places structuring Canadian cinematographic narratives. This analysis is based on the systematic study of a selection of 46 contemporary Canadian films. These films have been transformed into a database of 2200 places using an original geographic reading grid. Analysis of these places identifies the existence of territories under‐ and over‐represented by Canadian cinema, as well as territories of consensus and divergence that exist between different categories of Canadian cinema such as Quebecois, anglophone, and hybrid. Some interesting results include the general lack of interest in the southern hemisphere—notably Latin America—as well as in the Nordic territories (outside of First Nations cinema). It is also interesting to note the quasi‐absence of Vancouver on the screen, while Toronto and the United States appear recurrently. But the most striking result is probably the profound divergence in the way Canadian cinema treats the province of Quebec in general, and the city of Montreal in particular. Montreal is indeed the perfect example of a space of divergence: the city is heavily represented in Quebecois films, but completely ignored in the rest of Canadian cinematographic production. This deep opposition illustrates the importance of downtown Montreal as a symbolic space of Quebec national identity.  相似文献   

6.
Scholars frequently use counts of populations aggregated into geographic units like census tracts to represent measures of neighborhood context. Decades of research confirm that variation in how individuals are aggregated into geographic units can dramatically alter analyses conducted with these units. While most researchers are aware of the problem, they have lacked the tools to determine its magnitude or its capacity to affect analytical results obtained using these contextual measures. Using confidential access to the complete 2010 U.S. Decennial Census, we can construct—for all persons in the U.S.—individual-specific contexts, which we group according to Census-assigned block, block group, and tract. We compare these individual-specific measures to the published statistics at each scale, and we then determine the degree to which published measures could be affected by how boundaries are drawn using a simple statistic, the standard deviation of individual context (SDIC). For three key measures (percent Black, percent Hispanic, and Entropy—a measure of ethno-racial diversity), we find that block-level Census statistics frequently contain a high degree of uncertainty meaning that they may not capture the actual context of individuals within them. More problematic, we uncover systematic spatial patterns in the uncertainty associated with contextual variables at all three scales.  相似文献   

7.
孙飞翔  吕拉昌 《人文地理》2021,36(3):97-107
城市空间特征与创新的关系是创新地理的重要研究议题.论文构建了城市紧凑度与城市创新的理论分析框架,提出研究假设,并选取中国地级及以上城市作为研究空间单元,从密度、土地混合利用、街道连通性和交通通达性四个方面构建了城市紧凑度指数,对2010年中国城市紧凑度进行了评价,分析了中国城市紧凑度的空间分布特征,在此基础上,采用空间...  相似文献   

8.
9.
Ripley's K‐function is a test to detect geographically distributed patterns occurring across spatial scales. Initially, it assumed infinitely continuous planar space, but in reality, any geographic distribution occurs in a bounded region. Hence, the edge problem must be solved in the application of Ripley's K‐function. Traditionally, three basic edge correction methods were designed for regular study plots because of simplified geometric computation: the Ripley circumference, buffer zone, and toroidal methods. For an irregular‐shaped study region, a geographic information system (GIS) is needed to support geometric calculation of complex shapes. The Ripley circumference method was originally implemented by Haase and has been modified into a Python program in a GIS environment via Monte Carlo simulation (hereafter, the Ripley–Haase and Ripley–GIS methods). The results show that in terms of the statistical powers of clustering detection for irregular boundaries, the Ripley–GIS method is the most stable, followed by the buffer zone, toroidal, and Ripley–Haase methods. After edge effects of irregular boundaries have been eliminated, Ripley's K‐function is used to estimate the degree of spatial clustering of cities in a given territory, and in this paper, we demonstrate that by reference to the relationship between urban spatial structure and economic growth in China.  相似文献   

10.
Jenna M. Loyd 《对极》2011,43(3):845-873
Abstract: This paper traces how Los Angeles peace activists tried to make visible the grave domestic effects of Cold War militarization. Women Strike for Peace went beyond a focus on the productive relations between the state, military and industry captured by the term “military–industrial complex” to analyze how reproductive spaces were part of this complex. In opposing war, they challenged what I am calling militarized domesticities: how war‐making shapes the ‘home front’ and home as the spaces national security states claim to protect. I build on feminist antiracist intersectionality theories to situate the military–industrial complex per se within broader processes of the militarization of society and daily life. The questions become how do gendered processes of militarization—that work in conjunction with relations of white privilege—produce and connect differently situated “private” spaces or home places? How might strategies for dismantling the military–industrial complex emerge from the contradictions of these processes?  相似文献   

11.
Abstract: In this paper, we use insights derived from a critical evaluation of ecological modernisation theories to examine the origins and influence of new, market‐based, forms of carbon governance. Focusing on two key examples—emissions trading in Europe and the global market in offsets—we argue that ecological modernisation theories can help us understand the processes through which the seemingly intractable problem of climate change has been reframed as an opportunity to construct a new carbon economy and anticipate some of the tensions, contradictions and limits of such an approach. We then explore the governance dimensions of these novel market mechanisms, look at how they work, and then discuss whether, to what extent and for whom they work. We highlight a series of (un)‐intended consequences that flow from these practices and modes of governing. We conclude by discussing the significance of these observations both for debates on climate change and the governance of carbon and for theories of ecological modernisation.  相似文献   

12.
This review paper applies a critical geographic perspective to analysis of planning ambition and prospect. Its point of departure is that planning, an applied spatial science, has lacked consistent review from critical geography in recent decades. The consequences of this drift for planning conception and practice are considered, focusing on the influential construct, the compact city. The review finds evidence of serious epistemological and methodological flaws in planning thought and ambition; failings that were earlier identified and analysed in the break with positivism in geographical sciences. The consequences of these limitations for planning thought and practice are considered. Broadly they undermine the ability of the compact city ideal to address what is arguably the most critical threat facing humanity, climate change. Specifically, the proposition that urban density has straightforward influences on human behaviour, including resource use, is without scientific foundation. Planning has a critically important part to play in climate response: securing the resilience and well‐being of an increasingly urbanised human species. Urban compaction may not achieve these ends.  相似文献   

13.
Elleza Kelley 《对极》2021,53(1):181-199
This article attempts to analyse mapping practices at the intersection of geography, black studies and literary studies, in order to reassess the political and pedagogical possibilities of mapping under late capitalism. I turn to Toni Morrison’s novel Beloved to track black cartographic practices otherwise obscured or, as Katherine McKittrick writes, “rendered ungeographic”. The novel offers a hidden and unauthorised archive for the often clandestine geographic practices that make possible fugitivity from the mechanics of “slaveholding agro‐capitalism” and its ongoing legacy. As an unofficial archive of black geographic practice, Morrison’s novel might itself be thought of as a map: a contemporary mode of memorialising the depth of place, relation, and navigation—a depth no two‐dimensional map can accommodate. Finally, this article demonstrates the valuable interventions that black studies and black creative production can make within the subfields of critical cartography and critical geography.  相似文献   

14.
15.
Vinay Gidwani 《对极》2008,40(5):857-878
Abstract: Two Hegels inhabit the Grundrisse. The first is conservative of the “selfsame” subject that continuously returns to itself as non‐identical identity and propels “history”. The other Hegel tarries with the “negative” he (which or variously calls “non‐being”, “otherness”“difference”) to disrupt this plenary subject to Marx's reading of a Hegel who is different‐in‐himself lends Grundrisse its electric buzz: seizing Hegel's “negative” as the not‐value of value, i.e. “labor”, Marx explains how capital must continuously enroll labor to its will in order to survive and expand. But this enrollment is never given; hence, despite its emergent structure of necessity, capital's return to itself as “self‐animating value” is never free of peril. The most speculative aspect of my argument is that the figure of “labor” in Grundrisse, because of its radically open formulation as not‐value, anticipates the elusive subject of difference in postcolonial theory, “the subaltern”—that figure which evades dialectical integration, and is in some ontological way inscrutable to the “master”. Unexpectedly, then Grundrisse gives us a way to think beyond the epistemic and geographic power of “Europe”.  相似文献   

16.
The placement of facilities according to spatial and/or geographic requirements is a popular problem within the domain of location science. Objectives that are typically considered in this class of problems include dispersion, median, center, and covering objectives—and are generally defined in terms of distance or service‐related criteria. With few exceptions, the existing models in the literature for these problems only accommodate one type of facility. Furthermore, the literature on these problems does not allow for the possibility of multiple placement zones within which facilities may be placed. Due to the unique placement requirements of different facility types—such as suitable terrain that may be considered for placement and specific placement objectives for each facility type—it is expected that different suitable placement zones for each facility type, or groups of facility types, may differ. In this article, we introduce a novel mathematical treatment for multi‐type, multi‐zone facility location problems. We derive multi‐type, multi‐zone extensions to the classical integer‐linear programming formulations involving dispersion, centering and maximal covering. The complexity of these formulations leads us to follow a heuristic solution approach, for which a novel multi‐type, multi‐zone variation of the non‐dominated sorting genetic algorithm‐II algorithm is proposed and employed to solve practical examples of multi‐type, multi‐zone facility location problems.  相似文献   

17.
Initiatives aimed at protecting aquatic ecosystems often prove difficult to implement—particularly in water‐stressed, semi‐arid regions where the demand for water for human consumption is high. This article reports on an investigation of the factors that shaped the development and implementation of policies for aquatic ecosystem protection in the Oldman River Basin (ORB), a crucial watershed in semi‐arid southern Alberta. The analysis reveals critical cultural and historical considerations that confront those attempting to protect and restore aquatic ecosystems in the ORB and highlights specific factors that influence implementation of measures to protect it. In addition to the most basic consideration—demand for water exceeds supplies—eight specific factors that influenced aquatic ecosystem protection in this region are identified and evaluated. These include (1) clarity of actors’ roles/ jurisdictional responsibilities; (2) communication; (3) definition of key terms; (4) funding and organizational capacity; (5) leadership; (6) legal standing; (7) data and monitoring; and (8) public education. We argue that while these factors are important, critical cultural and historical considerations that influence water policy in the province also must be addressed in any efforts to protect aquatic ecosystems in southern Alberta.  相似文献   

18.
Starting from an econometric model of local employment growth, applied to Canada (1971–2001), residuals—relative to model predictions—are analyzed over time and over space, in turn allowing us to draw a distinction between general explanatory variables and factors of a more local, cyclical or accidental nature. The model's explanatory power grows over time, founded on variables such as urban size, market access and industrial structure, allowing us to conclude that local employment growth in Canada follows an increasingly geographically predictable pattern. However, an examination of the residuals reveals more localized processes. Growth volatility is most manifest in Alberta and British Columbia, home to the most erratic local economies. Emerging patterns are visible in the last period, most notably the underperformance of Northern Ontario and of non‐metropolitan communities between Windsor and Québec City, lying along the Great Lakes and the Saint Lawrence. The over‐performance—compared to model predictions — of small and mid‐sized towns in south‐eastern Québec can, on the other hand, be interpreted as a sign of truly local social processes, generally associated with a particularly dynamic local entrepreneurial class.  相似文献   

19.
This paper studies a set of wall‐paintings of the Late Bronze Age (c. 1650 bc ) initially decorating the internal walls of the third floor of the edifice called ‘Xeste 3’, excavated at Akrotiri, Thera, whose restoration is now in progress. It deals with the methods used for the drawing of the geometrical figures appearing in these wall‐paintings. It is demonstrated that most of the depicted configurations correspond with accuracy to geometrical prototypes such as linear spirals and canonical polygons. It is pointed out that the steady lines of the figures, their remarkable repeatability, the precision of the geometrical shapes and their even distribution in the wall‐paintings indicate a very distinctive use of the ‘Xeste 3’ third floor, which is now investigated.  相似文献   

20.
This paper examines the relative earnings and wages of immigrants working in the hi‐tech sector in Canada's cities. Between 1990 and 2000, a sizeable earnings advantage of immigrants over nonimmigrants employed in the hi‐tech sector evaporated, and this change was most noticeable in the largest cities. We use population census microdata to examine the geographical dimensions of this shift. After controlling for individual characteristics, we show that immigrants in the largest and tech‐intensive cities earn significantly less relative to nonimmigrants than those in midsized and smaller cities. We also present results comparing the hi‐tech immigrant wage and earnings gap for the five largest Canadian cities. The findings are consistent with the notion that geographic differences are an important component of the overall earnings gap between immigrants and nonimmigrants.  相似文献   

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