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In the Andes, there are several pre-Hispanic irrigation networks with structures destined for water storage. However, it has not been widely discussed in archaeological research. This is probably due to their being difficult to identify. The aim of this study is to explore the use of diatom assemblage analysis as a methodological tool suitable to help in the identification and characterization of these ancient hydraulic structures. We analyzed two archaeological structures interpreted as water reservoirs from north-western Argentina (EH1 in Antofagasta de la Sierra and U-88R1 in Yocavil) and compared them to current reservoirs. The diatom species composition and the changes in the dominant ecological groups in the studied structures highlight different periods of hydraulic behavior. EH1 contained and stored water, but there were periods of time in which there was a lack of use or abandonment of the structure. However, the U88-R1 structure does not have diatom evidence of containing standing water for a prolonged time but presence of wet soils. Thus, the structure could have been used for other water management strategies. The results show that diatom analysis is a methodological tool with a high potential to study ancestral hydrotechnologies.  相似文献   
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A simple mathematical expression is proposed to estimate spectra reduction damping factors for seismic design of systems with viscous dampers. The expression is obtained from the ratios between ordinates of uniform hazard spectra associated with two different return intervals (50 and 125 years), corresponding to sites with different types of soil within the Valley of Mexico. The expression proposed depends on the dominant period of the soil, and on both the vibration period and damping ratio of the structural system. Values of the damping factors proposed here are comparable to those recommended by different authors and seismic design building codes.  相似文献   
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Nadung’a 4 is one of the single carcass pachyderm sites recorded in East Africa during the Lower and Early Middle Pleistocene. The site has yielded an abundant lithic assemblage in close association with the partial carcass of an elephant. Conjoined pedological, geoarchaeological, spatial, technological, and taphonomical analyses have been carried out to address the relationship between hominids and elephant. The resulting data are consistent with a non-fortuitous association between both categories of remains. The lithic artefacts do not match a classical Acheulean tool-kit, as would be expected for the time period ascribed to the site, and the functional patterns inferred from their analysis make this site radically different from other purported butchery sites. The implications of these original features are discussed.  相似文献   
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The formerly sleepy, rural county of Oxfordshire is now one of Europe's leading centres of enterprise, innovation and knowledge. It is a hotspot for high-tech manufacturing and service employment. But what is behind this phenomenon, and to what extent has it been managed? This paper sets out the facts, and explores the underlying factors. It starts with a number of definitional questions and approaches used in the research. It concludes with an examination of the role of planning in the process—and the extent to which is has helped or hindered the rise of “Enterprising Oxford”.  相似文献   
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ABSTRACT Water is a resource that both unites and divides people in the Upper Hunter Valley of New South Wales, where many communities are facing the prospect of large‐scale open‐cut coalmining developments on productive mixed use land, or already live in proximity to mines and power stations. This article analyses conflicts over a proposed coal mine at Bickham in the Upper Hunter Valley, by contrasting the various protagonists' discourses of water scarcity, supply, and connectivity. It examines the ways in which the terms of opposition are narrowed to the arena of state and industry supported science and economic development, marginalising other cultural values and environmental ethics that are integral to opponents' discourses. Opponents have achieved some measure of success through contestation of the uncertain science of hydrological modelling, bolstered by the context of drought and increasing public acceptance of climate change science.  相似文献   
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