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951.
Current analogical data used to infer prehistoric human bone breakage rely on a plethora of experimental hammerstone‐broken bovid bone sets. Several criteria have been argued to be diagnostic of bone breakage by humans, among which the most important are: a specific range of broken specimens bearing percussion marks, a specific distribution of different percussion mark types, metric properties of notches, differential notch type distribution, and the angle of oblique breakage planes. The present work shows that those properties derived from the breakage of bovid bones cannot be universally applied to all types of animals. As an example, here it is experimentally demonstrated that hammerstone‐broken equid bones (with different thickness and structural properties compared to bovid bones) show different values in all these variables and some of them overlap with criteria documented in bones broken by static loading. This suggests that the agents of equid bone breakage are more difficult to identify, and that the number of variables that can be successfully used to that end is smaller than in bovid bones.  相似文献   
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We designed a geographical model for simulating the distribution of urban growth in systems of cities. The model incorporates the hierarchical and spatial diffusion of innovation cycles through gravitational interactions within a set of cities. Using theoretical simulations, we demonstrate that this model is able to reproduce the observed properties of urban systems for the log‐normal distribution of city sizes as well as the observed distribution of growth rates. Our experimentation was performed on a large harmonized historical database that includes a few hundred French urban agglomerations between 1831 and 1999 (Pumain‐INED database). Both spatial interaction and innovation cycles are necessary ingredients to explain the evolution of urban hierarchies. We suggest that Gibrat's generic stochastic growth model based on independent entities should be replaced by a more relevant model of spatially and temporally interdependent geographical entities.  相似文献   
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955.
QUANTIFYING KNOWLEDGE SPILLOVERS USING SPATIAL ECONOMETRIC MODELS   总被引:1,自引:0,他引:1  
ABSTRACT This paper seeks to develop our understanding of the somewhat diffuse nature of technological externalities and space by associating a geographical dimension with the sectoral dimension. Using a panel data set containing French patents as well as private and public research expenditures by industry and region over the period from 1992 to 2000, this paper estimates a knowledge production function. The region‐ and industry‐specific nature of the sample data allows us to empirically examine spatial spillovers associated with public and private research expenditures in own‐ and other‐industry sectors for our sample of 94 French regions. We find that the largest direct and indirect effects are associated with private R&D activity that spills across industry boundaries. However, since Jacobs externalities decrease more drastically with distance than MAR externalities, our results also point to different optimal strategies for regional versus national officials.  相似文献   
956.
In order to investigate the nature and organization of high‐status ceramic production in the Late Bronze Age, samples of Nuzi Ware from four different sites were analysed using scanning electron microscopy (SEM–EDS) and inductively coupled plasma atomic emission spectroscopy (ICP–AES). Chemical and mineralogical evidence suggests that Nuzi Ware was produced in at least two distinct regions, one probably in the Adhaim Basin in northern Iraq and another possibly in the Orontes catchment in southeastern Turkey. The existence of individual production units probably developed in response to the local elites' desire to imitate the tastes of the Mitanni aristocracy, resulting in a mapping of political relationships on to material culture.  相似文献   
957.
ABSTRACT. By analysing school memorial ceremonies in Israel, this article demonstrates how dominant groups in Israeli society (upper‐ and middle‐class, secular, educated Jews of European origin) exploit their historical monopoly over the Israeli warrior ethos in order to retreat from their unconditional commitment to the state and the military, which stands at the very core of traditional ‘heroic nationalism’. Nonetheless, despite their withdrawal from the military ethos, analysis of the school ceremonies shows that rather than distancing themselves from the national collective, they are promoting a different kind of nationalism – one that I term ‘traumatic nationalism’. This model departs from the warrior ethos and places mourning and a feeling of victimhood at its centre. Thus, through the arena of education, the dominant groups – which mark out the global as their sphere of action – promote a model of nationalism that meets the demands of the post‐national discourse.  相似文献   
958.
In this work, we studied coloured and colourless glass used as gems in Visigothic buckles possibly originating from the necropolises of Torredonjimeno, Duraton or Castilltierra in Spain. Scanning electron microscopy (SEM) with energy‐dispersive analysis (EDS) and observations made with an optical microscope in reflected and transmission mode were performed in order to establish the composition, origin of the colour and decay process of these glass pieces. The chemical analysis of ancient glass can provide relevant information regarding the manufacturing approach used during a specific period. The results revealed the presence of various transition metal elements used as chromophore elements, as well as some metallic backing foils used to improve the colour of pieces of almost colourless glass.  相似文献   
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