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71.
The aim of this article is to present an experimental approach for studying the formation and transformation processes of archaeological fire structures. We present a synthetic review of our experimental project, which was developed in many different natural archaeological contexts. We report the results and problems associated with experimental fires lit on different kinds of soils and in different environments, followed by the observation of natural and anthropic transformations. Finally, we analyse the nature and significance of these results for the archaeological interpretation process, while describing some general trends and showing the complexity of the approach.  相似文献   
72.
The question of how mass atrocities end has been dominated by a normative approach regarding how they ought to end. Arguing that an evidence-based approach to terminate mass atrocities might offer profound insights into theories of mass atrocities as well as policies designed to prevent or end their occurrence, this article outlines the key questions and approaches needed for an evidence-based study of atrocity endings. It draws on theories of genocide, political violence and civil war termination, and presents initial insights from case studies, including the killing of civilians in colonial German Southwest Africa, the Soviet Union, the Nigerian civil war, the Guatemalan civil war, the Nuba Mountains of Sudan and Bosnia-Herzegovina.  相似文献   
73.
This paper has two aims: to explore approaches to the measurement of children's daily travel to school in a context of limited geospatial data availability and to provide data regarding school choice and distance travelled to school in Soweto-Johannesburg, South Africa. The paper makes use of data from the Birth to Twenty cohort study (n?=?1428) to explore three different approaches to estimating school choice and travel to school. First, straight-line distance between home and school is calculated. Second, census geography is used to determine whether a child's home and school fall in the same area. Third, distance data are used to determine whether a child attends the nearest school. Each of these approaches highlights a different aspect of mobility, and all provide valuable data. Overall, primary-school-aged children in Soweto-Johannesburg are shown to be travelling substantial distances to school on a daily basis. Over a third travel more than 3 km one way to school, 60% attend schools outside of the suburb in which they live, and only 18% attend their nearest school. These data provide evidence for high levels of school choice in Johannesburg-Soweto, and that families and children are making substantial investments in pursuit of high-quality educational opportunities. Additionally, these data suggest that two patterns of school choice are evident: one pattern involving travel of substantial distances and requiring a higher level of financial investment and a second pattern involving choice between more local schools, requiring less travel and a more limited financial investment.  相似文献   
74.
This paper considers the “share‐altering” technical change hypothesis in a spatial general equilibrium model where individuals have different levels of skills. Building on a simple Cobb‐Douglas production function, our model shows that the implementation of skill‐biased technologies requires a sufficient proportion of highly educated individuals. Moreover, when technical progress disproportionately replaces middle‐skill jobs, the local distribution of skills will exhibit “fat‐tails,” where the proportion of both highly skilled and low‐skilled workers increases. These and several other predictions of the model are consistent with recent existing evidence, and avoid some major criticism against the “canonical” CES framework.  相似文献   
75.
This paper continues the characterization of the lead isotopic fingerprint of ancient copper mines in the north‐west of Spain. In this work, the lead isotopic compositions found in copper ores from the La Profunda mine are presented. Azurites and malachites sampled from this deposit were subjected to lead isotope analysis by multicollector ICP–MS. The results showed a clear radiogenic lead signature compatible with the presence of uranium‐rich minerals (such as zeunerite) in the same mining complex. Moreover, a rare copper artefact, found in the galleries of the mine during its modern exploitation, was also analysed and showed that local mineral was used for its manufacturing.  相似文献   
76.
This article presents a method to identify “Absolute and Relative Employment Concentration (AREC) areas” for a particular industry. Two novel characteristics of the method are that it simultaneously analyses AREC, and that it combines spatial concentration per area with the spatial concentration in neighbouring areas. The method is easy to understand and apply. It is developed to assist regional policy makers and corporate decision-makers with their investment decisions related to new infrastructure or plants. The identification of concentration areas also allows for analysing the performance of these areas in relation to characteristics such as infrastructure availability and the housing and labour market. This can yield new academic insights that are relevant for regional planners. An application of the newly developed method to five industries in a Dutch province subdivided into 502 areas illustrates the value of the method in comparison to other methods.  相似文献   
77.
In a talk given at Zurich in the late 1940s, Hermann Weyl discussed Ferdinand Gonseth's dialectical epistemology and considered it as being restricted too strictly to aspects of historical change. His experiences with post-Kantian dialectical philosophy, in particular Johann Gottlieb Fichte's derivation of the concept of space and matter, had been a stronger dialectical background for his own 1918 studies in purely infinitesimal geometry and the early geometrically unified field theory of matter (extending the Mie-Hilbert program). Although now Weyl distantiated himself from the speculative features of his youthful philosophizing and in particular from his earlier enthusiasm for Fichte, he again had deep doubts as to the cultural foundations of modern mathematical sciences and its role in material culture of high modernity. For Weyl, philosophical «reflection» was a cultural necessity he now turned towards Karl Jaspers' and Martin Heidegger's existentialism to find deeper grounds, similar to his turn towards Fichte's philosophy after World War I. The discussion in the late 1940s can be read as a kind of post-World-War-II «Nachtrag» to Weyl's more widely known philosophical comments on mathematics and the natural sciences published in the middle of the 1920s.  相似文献   
78.
79.
This paper explores how the expression of ‘capacity’ (mena, more commonly known as mana in other Oceanic settings) and the evocation of abundance are played out in relation to seasonal change and human‐environmental relations, as observed in the Torres Islands, Vanuatu. It considers the importance for communities of North and Central Vanuatu of the appearance of a ubiquitous sea worm known as the Palolo, in combination with the regular motions of the sun and the moon, the prevaling winds and various other ecological patterns. While human‐environmental relations are often mediated by the idea of mena, this also constitutes a basic social value that informs local senses of place and belonging. The study of temporality and environmental knowledge can help to de‐centre territorial notions of ‘place’ by situating this concept within the broader context in which people experience it. Finally, because these data bear on macro comparisons that span the Western Pacific, this article is aimed in part at putting the interpretation of time and calendrics within the Indo‐Pacific frame of reference that they should begin to take.  相似文献   
80.
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