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Spatial Cluster Detection in Spatial Flow Data   总被引:2,自引:0,他引:2       下载免费PDF全文
As a typical form of geographical phenomena, spatial flow events have been widely studied in contexts like migration, daily commuting, and information exchange through telecommunication. Studying the spatial pattern of flow data serves to reveal essential information about the underlying process generating the phenomena. Most methods of global clustering pattern detection and local clusters detection analysis are focused on single‐location spatial events or fail to preserve the integrity of spatial flow events. In this research we introduce a new spatial statistical approach of detecting clustering (clusters) of flow data that extends the classical local K‐function, while maintaining the integrity of flow data. Through the appropriate measurement of spatial proximity relationships between entire flows, the new method successfully upgrades the classical hot spot detection method to the stage of “hot flow” detection. Several specific aspects of the method are discussed to provide evidence of its robustness and expandability, such as the multiscale issue and relative importance control, using a real data set of vehicle theft and recovery location pairs in Charlotte, NC.  相似文献   
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Climate engineering, or geoengineering, refers to large-scale climate interventions to lower the earth's temperature, either by blocking incoming sunlight or removing carbon dioxide from the biosphere. Regarded as ‘technofixes’ by critics, these strategies have evoked concern that they would extend the shelf life of fossil-fuel driven socio-ecological systems for far longer than they otherwise would, or should, endure. A critical reading views geoengineering as a class project that is designed to keep the climate system stable enough for existing production systems to continue operating. This article first examines these concerns, and then goes on to envision a regime driven by humanitarian agendas and concern for vulnerable populations, implemented through international development and aid institutions. The motivations of those who fund research and implement geoengineering techniques are important, as the rationale for developing geoengineering strategies will determine which techniques are pursued, and hence which ecologies are produced. The logic that shapes the geoengineering research process could potentially influence social ecologies centuries from now.  相似文献   
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A specialist on financial issues in the State of Bosnia and Herzegovina assesses economic performance in that country during the five years following conclusion of the Dayton Peace Accords. The basic provisions of the Accords relating to economic activity and post-war reconstruction are presented, after which the analysis focuses on developments in the economy, privatization, and banking-sector reform, to the extent that available data allow. Coverage then turns to a review of the role of the Office of the High Representative in administration of the State's two constituent Entities: the Federation of Bosnia-Herzegovina and the Serb Republic. Journal of Economic Literature, Classification Numbers: O11, O18, O52. 5 tables, 33 references.  相似文献   
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ABSTRACT A belief that EU integration is incomplete is often predicated on a comparison to U.S. states. Yet, with low barriers to trade and factor mobility between EU countries, is this belief correct? To address this question, we develop three theoretical predictions regarding the distribution of output and factors across members of an integrated economic area with harmonized policies and free movement of goods and factors. Empirical tests strongly support these predictions for U.S. states and 14 EU countries. Constructing a measure of integration, we find that EU integration rose from the 1960s to equal that of U.S. states by 2000.  相似文献   
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