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61.
Manuel Vaquero Susana Alonso Sergio García-Catalán Angélica García-Hernández Bruno Gómez de Soler David Rettig María Soto 《Journal of archaeological science》2012
Recent research in Paleolithic archeology has stressed the importance of temporal issues in assemblage interpretation. Archeological assemblages are temporal constructs, formed by the addition of an unknown number of depositional events. This temporal dimension is also evident at the artifactual level, since single artifacts may undergo different events of modification and/or uses over time. The recycling of previously discarded blanks for tool production is one of the best examples of the temporal nature of artifacts. The aim of this paper is to evaluate the importance of recycling in a Late Upper Paleolithic site, examining a type of artifact – burned tools – that has up to now been little used to approach this issue. Our results suggest that recycling was probably a significant component of Upper Paleolithic provisioning behavior, with important implications in site formation processes and the typological variability of assemblages. The expedient or curated character of recycling is also discussed. 相似文献
62.
José Antonio Rodríguez Martín María Del Mar Holgado Molina José Antonio Salinas Fernández 《European Planning Studies》2012,20(6):1059-1074
In this article we calculate an indicator of social and economic development using the DP2 distance method to measure the disparities in Objective-1 regions of southern European countries for 2006. In addition to per capita income, socio-economic components such as health, education, employment, scientific and technological development and infrastructure provision have been incorporated into the index. We examine the issue of whether the Europe Union regions included in the Convergence Objective achieved a lower level of development than the regions no longer covered in this objective for the 2007–2013 programming period by establishing a territorial classification based on the value yielded by the variables of the DP2. Our indicator constitutes a novel contribution insofar as it was constructed using a large number of variables. In essence, we show that not all the regions of the Convergence Objective presented a lower level of economic and social development than those that lost this consideration between 2007 and 2013 and the opposite. 相似文献
63.
The p‐regions problem involves the aggregation or clustering of n small areas into p spatially contiguous regions while optimizing some criteria. The main objective of this article is to explore possible avenues for formulating this problem as a mixed integer‐programming (MIP) problem. The critical issue in formulating this problem is to ensure that each region is a spatially contiguous cluster of small areas. We introduce three MIP models for solving the p regions problem. Each model minimizes the sum of dissimilarities between all pairs of areas within each region while guaranteeing contiguity. Three strategies designed to ensure contiguity are presented: (1) an adaptation of the Miller, Tucker, and Zemlin tour‐breaking constraints developed for the traveling salesman problem; (2) the use of ordered‐area assignment variables based upon an extension of an approach by Cova and Church for the geographical site design problem; and (3) the use of flow constraints based upon an extension of work by Shirabe. We test the efficacy of each formulation as well as specify a strategy to reduce overall problem size. 相似文献
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66.
Tarek Ben Hassen Juan‐Luis Klein Diane‐Gabrielle Tremblay 《The Canadian geographer》2011,55(4):439-456
This article analyzes the mechanisms through which metropolitan governance is established in Montreal's aeronautics sector, one of the most important and innovative industries in the region. The article also examines the role of lead firms, socio‐economic actors, and public agencies from a territorial point of view. It is established that on the one hand the existence of a small number of prime producers at the local level facilitates productive linkages among businesses through subcontracting, and on the other hand, the intensive participation of intermediate socio‐economic agencies and organizations ensures a metropolitan anchoring of the sector and creates a strong territorial identity among the players. 相似文献
67.
Ground-supported steel tanks experienced extensive damage in past earthquakes. The failure of tanks in earthquakes may cause severe environmental damage and economic losses. This study deals with the evaluation of the elastic buckling of above-ground steel tanks anchored to the foundation due to seismic shaking. The proposed nonlinear static procedure is based on the capacity spectrum method (CSM) utilized for the seismic evaluation of buildings. Different from the standard CSM, the results are not the base shear and the maximum displacement of a characteristic point of the structure but the minimum value of the horizontal peak ground acceleration (PGA) that produces buckling in the tank shell. Three detailed finite element models of tank-liquid systems with height to diameter ratios H/D of 0.40, 0.63, and 0.95 are used to verify the methodology. The 1997 UBC design spectrum and response spectra of records of the 1986 El Salvador and 1966 Parkfield earthquakes are used as seismic demand. The estimates of the PGA for the occurrence of first elastic buckling obtained with the proposed nonlinear static procedure were quite accurate compared with those calculated with more elaborate dynamic buckling studies. For all the cases considered, the proposed methodology yielded slightly smaller values of the critical PGA for the first elastic buckling compared to the dynamic buckling results. 相似文献
68.
Manuel Schramm 《Folklore》2013,124(1):64-76
This article attempts to historicise the concept of “folk art” using the example of wooden toys from the Erzgebirge mountains to show that it was invented by cultural élites as a marketing concept at the beginning of the twentieth century in order to support a domestic industy caught in structural crisis. 相似文献
69.
This essay considers the ways in which the reception of Virgil's Georgics in eighteenth-century English verse may inform, enrich and complicate present-day readings of Virgil, focusing on questions raised by readers’ detection of wit or humorousness in Virgil and by the critical aim of discovering poetic unity in the Georgics. 相似文献
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