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51.
We present novel imaging results from a non-invasive examination of three ‘pattern-welded’ swords from the Viking Age belonging to the National Museum of Denmark, using white beam and energy resolved tomographies with neutrons. Pattern-welded blades are made by forge welding together thin strips of iron and steel that were twisted and joined in various ways, producing a decorative pattern on the surface. The study shed light on the inner structure of the composite material and manufacturing techniques of these admired examples of past technology, revealing some otherwise invisible details of their assembly methods, phase distribution and extent of the corrosion.  相似文献   
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Understanding sailing conditions is a basic requirement for understanding the two periods of settlement of the distant islands of Oceania, initially from the Bismarck Islands off New Guinea as far as Samoa and later from Samoa throughout East Polynesia. The question of a “navigational threshold” between these two worlds is the focus of this paper. A computer simulation is presented that quantifies the difficulty of sailing virtual canoes in the differing wind conditions in both areas. The model demonstrates substantial differences in ease of voyaging up to and beyond Samoa. That this measure is so markedly different between these two worlds gives support for the hypothesised pause between the discovery and settlement of islands West and East of Samoa.  相似文献   
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Grimmer-Solem  Erik 《German history》2007,25(3):313-347
German economists led by Gustav Schmoller created the KolonialpolitischesAktionskomité (colonial-political action committee) duringthe so-called ‘colonial crisis’ of 1906–1907to promote the German colonial empire at a time when it wassuffering much scandal and criticism. Widely esteemed and enjoyingthe appearance of non-partisanship, they worked closely withthe government of Bernhard von Bülow during the electionsof 1907, arguing that colonial empire was economically and politicallyindispensable and that its financial burdens were bearable.Straddling a position between the economic imperialism of manyGerman liberals and the settler colonialism prevalent in conservativeand radical nationalist circles, they helped secure a middleground that enabled the Bülow bloc and developed many ideasfor colonial reform that came into currency during the Dernburgera (1906–1910). Through lecturing, the mass disseminationof relatively high-quality literature, and the demarcation ofthe new academic sub-discipline known as Kolonialwissenschaft(colonial science), a potent complex of liberal-nationalistambitions was fused with a new ‘scientific’ colonialismthat helped redefine and legitimate a German civilizing missionin Africa and forge an imperialist ideology that gained a nationalaudience.  相似文献   
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There has been an impressive stride in the research on policy feedback effects on mass publics over recent years. However, we lack systematic evidence on how large such policy feedback effects are in the literature. This article provides a review of 65 published studies and quantifies the findings and key themes in the policy feedback literature. The results show a great degree of heterogeneity in the domains and outcomes being studied and in the effects of policies on the public. In line with the findings from narrative reviews, feedback effects are greater for outcomes related to political participation and engagement. Last, the review sheds light on important theoretical and methodological limitations to be addressed in future research.  相似文献   
56.
The concept of the Daily Urban System (DUS) has gained relevance over the past decades as the entity to examine and explain the functionality of the urban landscape. Daily Urban Systems are usually defined and measured by the strength of commuter or shopper flows between the nodes of the system. It is important to realize that these Daily Urban Systems are the accumulated pattern of individuals making frequent, recurring trips to other localities than their own. Understanding the microeconomic decisions behind these spatial interactions will help in assessing the functional and spatial structure of DUS. In this paper is explored how, based on Dutch empirical data, the individual household’s spatial interactions shape the daily urban system and how the destination of these interactions correlates with personal and spatial variables and motives for interaction. The results show that the occurrence of non-local spatial interactions can be explained by the size-based Christallerian hierarchy of the localities of residence, but that it is the regional population – or market potential – that explains and moderates the sorting of households and the intensity and direction of their spatial interactions in the DUS, matching agglomeration theory.  相似文献   
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Historical evidence of aeolian activity in the outer coastal zone of Jæren, southwest Norway, is presented. Meteorological factors such as wind force and wind direction are discussed. Special attention is devoted to meteorological factors causing drought (evaporation and precipitation) as a necessary condition for the occurrence of sand drift. Several aeolian periods after 6000 BP have been identified in the sediments along the coast of Jæren. It is suggested that the changes in the aeolian activity observed have arisen from changes in the environmental state, such as lowering sea level, climatic variation and environmental stress caused by man's interference in connection with increasing agricultural activity (forest clearing, cultivation and so on).  相似文献   
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In this article, the hypotheses put forward in ‘A Theoretical Approach’ in Volume 1 of this Journal are tested. An account is first given of the additional settlements and hoards which were treated in the computer. The combined material consists of 17 units. The material is then evaluated and handled in a number of experiments in which various methods of arriving at special tendencies in the material are considered. Finally the various methods selected are discussed and the results summarised.  相似文献   
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