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21.
The superposition of anthropogenic remains usually results in archaeological palimpsests, hindering an accurate characterization of the behavior underlying such remains. Aimed at facing this methodological constraint in the study of Palaeolithic contexts, we present a contextual approach to Neanderthal settlement dynamics based on an understanding of lithic assemblage formation processes. We focused on a set of lithic artifacts from the Middle Palaeolithic site of El Salt. With the goal of isolating temporally constrained units of behavioral analysis, we analyzed the spatial distribution of lithic, faunal and combustion remains. Then, the lithic records from each of the resulting units were analyzed from a genetic and technical perspective. This goal was achieved by identifying lithic Raw Material Units (RMU) through observations on reduction processes, refits and their spatial distribution. Our results suggest that El Salt SU X lithic remains represent several diachronic human occupation episodes and different site functions. This study illustrates the benefit of investigating lithic assemblage formation processes to alleviate the palimpsest problem in Palaeolithic contexts.  相似文献   
22.
Over the last decade, a long-running archaeological project in the Guadalquivir Basin (Spain) has identified the emergence (c. 3000 BC) and collapse (between c. 2500 and c. 2300 BC) of a regional inter-settlement hierarchical system centred on the south-western Pyrite Belt and the Lower Guadalquivir Basin.  相似文献   
23.
    
The recording and 3D modelling of complex archaeological sites is usually associated with high capital and logistical costs, because the data acquisition must be performed by specialists using expensive surveying sensors (i.e., terrestrial laser scanners, robotic total stations and/or ground‐penetrating radar). This paper presents a novel, low‐cost, user‐friendly photogrammetric tool for generating high‐resolution and scaled 3D models of complex sites. The results obtained with unmanned aerial vehicle (UAV) photogrammetry of an archaeological site indicate that this approach is semi‐automatic, inexpensive and effective, and that it guarantees quality.  相似文献   
24.
  总被引:1,自引:0,他引:1  
This paper evaluates the impact of accessibility on the productivity of Spanish manufacturing firms. We suggest the use of accessibility indicators of workers and commodities, integrating transport, land use, and individual components, computing real distances or traveling times using the Spanish full road network. Estimated firms’ total factor productivity is explained as a function of the accessibility indicators and additional control variables. Results evidence the crucial role on firms’ productivity to the accessibility of commodities and to a slightly lesser extent the workers.  相似文献   
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26.
  总被引:2,自引:0,他引:2  
Abstract We formulate a microeconomic model of residential location choice behavior as an aggregate of the individual behaviors of household members, subject to individual time constraints and a common income budget. A simplified version of the model is estimated from stated preference rank‐order data, yielding a function that may be interpretated as a conditional indirect utility function. We consider Box‐Tukey transformations, segmentation by income class, and a consistent treatment of data at different rank depths using the simultaneous mixed‐estimation method. Measures of the household's willingness‐to‐pay (through rents) for reducing travel times to work and study in the short run, are interpreted as subjective values of time and compared with such values derived from mode choice models. Our results are plausible, and consistent with recent findings showing that the short‐run benefits of transport projects derived by transport models are larger than benefits measured at the land use system.  相似文献   
27.
    
This study reviews several effects stones have on slope geomorphic processes and plant distribution at high elevations, with emphasis on low‐latitude mountains and volcanic environments and rosette plants. It begins by considering how vegetation becomes established on relatively stable footslopes and the principal influences that outcrops and isolated boulders have on slope movement and vegetation development, moves to a comparison of the principal geomorphic processes affecting stone‐covered slopes and the disturbance agents influencing fine‐sediment zones that are devoid of clasts. The significance of stones for plant survival in areas subjected to frost activity, the strategies displayed by plants growing in unstable talus zones and the impacts stones have on plant development and slope dynamics are also considered. The study concludes by examining the role stones play in providing safe sites for plant development and the expansion of ecological niches, and with some speculations on possible future research directions.  相似文献   
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ABSTRACT In industrializing regions, foreign investments often generate spillovers through regional backward links. This situation may create a gap between private and social valuations of resources, resulting in a level of local content below what would be optimal for the economy. This situation creates an opportunity for the enactment of domestic content regulations. This paper presents a model to understand how these policies condition the decisions of the economic agents and affect economic welfare. Then, it simulates the model using a case study of the automotive sector. Results suggest that, in certain conditions, this local content regulation can be welfare enhancing.  相似文献   
29.
    
We analyse a half‐century of Chilean urban reforms to explain the introduction of a system of urban accumulation by dispossession of public resources and opportunities. Three stages have been conceptualised in the imposition of a neoliberal creative‐destructive process: proto‐neoliberalism, roll‐back and roll‐out periods. Empirical studies have traditionally analysed this process by examining a single urban policy's evolution over time. In this paper, we go beyond these types of studies by performing a systemic analysis of multiple urban policy reforms in Santiago, Chile. We use a genealogical thematic analysis to track changes in laws, government programmes and planning documents from between 1952 and 2014. Our analysis identifies different “urban systems of accumulation” by looking at the interplay of four urban policies: (1) urban planning deregulation; (2) social housing privatisation; (3) devolution of territorial taxes; and (4) decreased public service provision. Moreover, our multidimensional policy analysis in Santiago characterises a more radical, fourth expression in the creative destruction process of “accumulation by dismantling”. Consequently, we advocate for more multidimensional urban policy research that goes beyond a three‐period analysis in order to gain a deeper understanding of contemporary neoliberal creative‐destructive processes in variegated geographies.  相似文献   
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