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11.
    
This study introduces a new measure of urban centrality. The proposed urban centrality index (UCI) constitutes an extension to the spatial separation index. Urban structure should be more accurately analyzed when considering a centrality scale (varying from extreme monocentricity to extreme polycentricity) than when considering a binary variable (monocentric or polycentric). The proposed index controls for differences in size and shape of the geographic areas for which data are available, and can be calculated using different variables such as employment and population densities, or trip generation rates. The properties of the index are illustrated with simulated artificial data sets and are compared with other similar measures proposed in the existing literature. The index is then applied to the urban structure of four metropolitan areas: Pittsburgh and Los Angeles in the United States; São Paulo, Brazil; and Paris, France. The index is compared with other traditional spatial agglomeration measures, such as global and local Moran's I, and density gradient estimations. El presente estudio introduce una nueva medida de centralidad. El índice de centralidad urbana propuesto (UCI, por sus siglas en inglés) es una extensión al índice de separación espacial (spatial separation index)(Midelfart‐Knarvik et al. 2000). El análisis de la estructura urbana resulta más preciso al usar el índice cuando se toma en cuenta una escala de continua de centralidad (que puede variar de un monocentrismo extremo a un policentrismo extremo) que cuando se considera una variable binaria (monocéntrica o policéntrica). El índex propuesto controla las diferencias de tamaño y forma de las áreas geográficas de las que se tienen datos, y puede ser calculada utilizando diferentes variables, como empleo y densidad poblacional, o tasas de generación de viajes. Las propiedades del índice se ilustran con conjuntos de datos artificiales simulados, y se comparan con otras mediciones similares en la literatura ya existente. Posteriormente, el índice es aplicado a la estructura urbana de cuatro áreas metropolitanas: Pittsburgh y Los Ángeles, en EEUU; San Pablo, en Brasil; y París, Francia. Finalmente, se compara el índice con otras mediciones tradicionales de aglomeración espacial, como el índice de Moran local y global, y estimaciones de gradiente de densidad. 本文介绍了一种度量城市中心性的新方法,提出的城市中心性指数(UCI)是对空间分离指数的扩展。当涉及到中心性规模(从极单中心到极多中心),不仅仅是二元变量(单中心或多中心),城市结构则需更加精确的测度。本文构建的指数可以通过数据可获取的不同大小和形状的地理单元控制,并通过不同变量(如就业与人口密度或者旅次产生率)测算得到。该指数的属性可以通过人工数据集的模拟示例说明,或者通过对比已有文献对相似指数的阐述加以说明。然后,通过将该指数应用于全球四个大都市区(美国匹兹堡和洛杉矶、巴西圣保罗和法国巴黎)的城市结构中进行检验。最后,将该指数与其他测度传统空间集聚指数如全局和局部Moran指数及密度梯度估计进行对比.  相似文献   
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In 2011, Huu‐ay‐aht First Nations became one of five Nuu‐chah‐nulth Nations on the west coast of Vancouver Island in Canada to implement the Maa‐nulth Treaty with the Province of British Columbia and Canada. Modern treaties are dense and lengthy legal documents that exhaustively set out the obligations of each signatory party. They are heavily criticised for being unjust extensions of colonialism that limit Indigenous self‐determination and transform homelands under settler colonial property regimes. Yet, some First Nations accept these agreements as their chosen path for self‐government in state structures. We document Huu‐ay‐aht First Nations’ decision‐making that resulted when the Maa‐nulth Treaty was implemented and replaced the Indian Act by analysing the Maa‐nulth Treaty and interviews conducted with Huu‐ay‐aht First Nations leadership. We demonstrate how ?iisaak (respect) and ?uu?a?uk (taking care of) guided Huu‐ay‐aht First Nations’ self‐government, while nesting this discussion in the complexities and critiques of modern treaties.  相似文献   
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There are more than 40 iron files known from the pre-Roman Iron Age in England, of which 26 come from settlements with evidence of manufacturing activities. The files vary considerably in size and form. The coarse-cut files were probably intended for working soft or fibrous materials such as wood or horn, whereas the finer-cut files were probably for working more compact or harder materials, including metals. This corresponds to the metallographic evidence from a sample of 17 files, of which only seven finer-cut ones have been found to be quench-hardened. The discovery of metal particles in five files provides further evidence of use.  相似文献   
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Alongside the burgeoning secular ideas on people and state during the Constitutional Revolution, a movement seeking a modern Islamic state, governed according to the shari'a, also emerged. This article studies the evolution of that movement in Isfahan, first by contrasting the experience of two brothers of very different ages, Aqa Najafi Isfahani and Haj Aqa Nurullah Isfahani, and examining the way the younger became receptive to the Pan-Islamic ideas then current in the Middle East. Second, the article considers in particular the political theory of Aqa Nurullah, which was influenced by his practical experience of institutional innovation in Isfahan. He argued that constitutionalism was implicit to Islam and saw it as generating wealth for Muslims. He also advocated many of the features of later Islamism, including the desire for a strong army.  相似文献   
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Lost after partial destruction by dredging in 1970, Arade 1 was a priority for the Centro Nacional de Arqueologia Náutica e Subaquática (CNANS). The upper part of the hull, lying over a 7-m-long area of the bed of the Arade river, was fully observed and recorded during the first two seasons (2001 and 2002) and dismantled in a third phase (2003). The 2004 and 2005 seasons aimed at the excavation, full recording and dismantling of the lower hull, briefly observed at the end of 2002. This second, detached, portion of the hull, was buried in the sediment and corresponds to midships.
© 2008 The Authors  相似文献   
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I would hope that the nations of the world might say that we had built a lasting peace, based not on weapons of war but on international policies which reflect our own most precious values. These are not just my goals, and they will not be my accomplishments, but the affirmation of our nation's continuing moral strength and our belief in an undiminished, ever-expanding American dream. 1
President Jimmy Carter, Inaugural Address, 20 January 20, 1977  相似文献   
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As part of a larger project promoting the development of historical dendrochronology in the Iberian Peninsula, ship‐timbers from the Arade 1 wreck (mostly planking and framing elements), stored at the DANS/IGESPAR in Lisbon, were examined. Of these, 52 samples were identified as deciduous oak (Quercus subg. quercus) and two as chestnut (Castanea sativa). Of 24 timbers selected for dendrochronological research, 23 could be dated, placing the origin of the wood in western France and the felling of trees between AD 1579 and 1583. Their homogeneity suggests they are part of the original construction, which probably took place shortly after AD 1583. © 2012 The Authors  相似文献   
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