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61.
A copper‐alloy thimble was found in 2010 at Punta Secca, Sicily, in a sealed context datable by coins to the first quarter of the seventh century AD. It has generally been thought that thimbles did not reach the Mediterranean area until the ninth century AD, but at least nine metal examples are in fact attested at various places from contexts datable between the late sixth century and the early ninth. It is suggested that the increasing use of silk in clothing in the Byzantine Empire during the seventh century, probably accompanied by the use for the first time of steel needles which made the use of a finger protector imperative, explains the apparent introduction of thimbles at this time. No securely dated metal thimbles are known from sites of Roman date, except for one at Ephesus of c.AD 100. It is very tentatively suggested that this last example might represent an import from China, where thimbles (and steel needles) are attested from at least the third century BC onwards.  相似文献   
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Japhy Wilson  Manuel Bayón 《对极》2018,50(1):233-254
This paper explores the entanglement of ideology and materiality in the production of the spaces of 21st century socialism. “Millennium Cities” are currently being constructed for indigenous communities throughout the Ecuadorian Amazon, with revenues derived from petroleum extracted within their territories. As iconic spatial symbols of the “Citizens’ Revolution”, the Millennium Cities would appear to embody “the original accumulation of 21st century socialism”—a utopian state ideology promising the collective appropriation of natural resources without the dispossession of the peasantry. Drawing on extensive field research, we argue that they are better understood as a simulation of urban modernity that is symptomatic of the predominance of ground rent in South American capitalism, and which conceals the violent repression of an autonomous indigenous project of petroleum‐based modernization. The original accumulation of 21st century socialism can therefore be interpreted as a “fantasy of origins”, which functions to reproduce the primitive accumulation of capital.  相似文献   
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Ground-borne vibrations induced by mine blasting are typically of low amplitudes, which are not considered a major concern for modern engineered structures. However, historic structures are often considered more vulnerable due to inadequate knowledge regarding the state of construction materials and structural response. Specifically, the construction materials used might be fragile or have deteriorated to a stage that could be vulnerable to such vibrations. Simplistic rule based on peak ground motion parameter has been adopted worldwide for safety assessment, while the frequency characteristics of vibrations are not taken into account. Further, there is very limited study on response of heritage structures to near-field blasting. This article presents a practical structural vulnerability assessment method for mine blast-induced vibrations. In particular, a design response spectrum model is proposed based on close range measurements of nearby mine blasting, which is compared with an existing design spectrum model for far-field mine blasts and a typical design spectrum model for earthquake actions. The method is illustrated through a case study of heritage masonry buildings in Australia. The unique blast data presented and the generalized methodology would be useful to both structural engineers and blast engineers in considering potential effects of blasting on heritage structures.  相似文献   
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Chronology building has long served as a major focus of archaeological interest in the Central Illinois River valley (CIRV) of west-central Illinois. Previous methods have relied primarily upon relative dating techniques (e.g., ceramic seriation) as a means of sorting out temporal relationships between sites. This study represents the first investigation into the utility of Bayesian techniques (which consider radiocarbon dates in context with archaeological information) in the CIRV. We present the results of a detailed ceramic seriation of the region, data that we use as a priori information in our Bayesian models. We then offer contiguous, overlapping, and sequential models of site occupations in the Mississippian CIRV, review the output and appropriateness of each model, and consider their implications for the pace of sociopolitical change in the region.  相似文献   
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