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41.
Previous research acknowledges the ancient and complex land-use history of European mountainous areas, which are characterised by a remarkable regional variability in terms of human practices and patterns of occupation during the Holocene. However, the combined palaeoenvironmental and archaeological study of highland human management at a micro-regional scale remains a largely unexplored research field, especially in the Pyrenees. A combined pollen, stomata, non-pollen palynomorphs (NPPs) and macrocharcoal study was carried out at three nearby alpine and subalpine peat basins from a relatively small territory (ca.1700 ha) at the Madriu valley (Andorra, eastern Pyrenees), following a fine spatial-resolution strategy. The purpose was to test the suitability of high altitudinal palaeoecological sequences when reconstructing past small-scale land-use variability. The palaeoecological results of those peat records are compared and further integrated with archaeological local data, and together underline the marked complexity of high mountain land-use system over the Holocene period. Main phases of micro-regional land-use and landscape variability can be distinguished from the middle Neolithic to the early Bronze Age and from the Roman Period to the Modern Era. Conversely, several phases of homogeneous landscape management are distinguishable during the early Neolithic, and from the late Bronze to the late Iron Age. Results drawn from this study show that landscape variability is not necessarily connected to topographic or climatic parameters, and underline the role of social, economical and cultural parameters in the land-use organisation and the landscape shaping of high mountain spaces since Prehistory.  相似文献   
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In recent years, there has been a growing interest in the problems caused by the existence of instability in cross-sectional regressions. The results about local autocorrelation measures are part of this debate, as are the proposals concerning the concept of geographically weighted regressions. This article also deals with the problem of stability (or the lack thereof), but focusing the discussion on the supposition of constancy in the parameter of spatial dependence. In most cases, this assumption is treated, with the risks that this involves, as a maintained hypothesis, which should be ascertained before continuing with the modeling exercise. In the article, we present a simple heterogeneity test for this type of parameters, based on the Lagrange Multiplier principle. To illustrate its use, we take the distribution of per capita income among the European regions as our discussion case. According to our results, there are clear signs of structural breaks in the spatial distribution of this variable and the scale factor and the autocorrelation coefficient appear to be principal actors.  相似文献   
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Timber-framed wall buildings are seen all over Europe, especially in seismic regions, given its adequacy to resist earthquakes. The “Pombalino” buildings, developed after the great 1755 earthquake that destroyed Lisbon, constitute one of the best examples of historic seismic-resistant structures based on timber-framed masonry walls. The research presented in this article aimed at experimentally evaluating the seismic behavior of the “Pombalino” buildings. The experimental program was based on extensive dynamic testing on sub-structures of typical “Frontal” walls (the timber masonry walls), carried out at the LNEC (the Portuguese National Laboratory of Civil Engineering) shaking table. The tests comprised (a) seismic tests, in which the seismic action was applied with increasing amplitude in one direction; and (b) dynamic identification tests, aiming at evaluating the dynamic properties of the sub-structures and their evolution with damage accumulation.  相似文献   
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Fire safety is an important issue of building safety, especially when the building’s fire load contents enhance the risks of fire deflagration. When existing timber structures are involved, the most usual way to improve its reaction to fire is to treat wood with fire retardants. This study focuses on the surface protection of existing timber roof structures against fire, through the use of fire retardant (FR) treatments applied on site. An experimental investigation was carried out to study the effect of FR treatments on timber reaction to fire, with a special emphasis on timber members with biological deterioration and previously treated with preservative products. The behaviour and effectiveness of intumescent and non-intumescent treatments was also investigated. The study showed that the application of FR treatments improved the reaction to fire of timber, even in the presence of previous preservative treatments. However, the choice of the specific FR treatment should take into account the substrate conditions. In addition, test results suggest that protection systems involving multi layers (intumescent and non-intumescent) with different functioning modes each are likely to have a good global performance on the protection of timber elements against fire.  相似文献   
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Ana Moragues‐Faus 《对极》2017,49(2):455-476
In the context of apolitical tendencies in food studies, this paper explores how alternative food networks can contribute to developing emancipatory food politics rather than constitute a tool to reproduce neoliberal subjectivities. For this purpose, I contend that the post‐political literature offers a useful approach to examining the concept of food politics by developing a more robust theoretical framework, permitting the establishment of linkages with broader contemporary processes of social change. The analysis of an action‐research process with buying groups in Spain is used to examine the “politics of collectivity” at play, that is, how these initiatives institutionalise “the political”. Specifically I explore the motivations mobilised to construct place‐based ethical repertoires and unveil how these groups govern the relationality of consumption practices in the pursuit of broader processes of change. I conclude by discussing the contribution of these initiatives to building egalitarian food democracies.  相似文献   
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