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81.
大都市区民宿和酒店业的空间竞争区位识别及其态势驱动力解析是实现都市旅游住宿业多业态共赢与全域可持续的重要现实条件。本文利用GIS空间分析技术和地理探测器,从微观尺度刻画上海市民宿和酒店业的空间竞争格局演化特征并探测其影响因素。研究发现:①上海市民宿业和酒店业集聚热点均趋向群集演化,民宿业历经“零星单点、单核、双核引领+郊区多组团”演化阶段且具有显著的景区指向性;酒店业历经“单核、单核强化、面状集聚+点状环绕”演化阶段且具有显著的城市商业中心指向性;②民宿业与酒店业的空间竞争程度加剧,竞争范围扩大,竞争形式由酒店业近乎垄断的空间剩余竞争发展为空间非剩余竞争和剩余竞争并存,最终形成空间竞争与错位共生并存状态。③文旅禀赋、商业设施和人口集聚是影响民宿和酒店业微观布局的主要因素,地价和交通条件的影响次之;经营理念、客群定位、经济实力以及空间载体差异是造成民宿和酒店业格局分异的隐性宏观动因。  相似文献   
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Pre‐Romanesque murals at Kosto?any pod Tríbe?om, Slovakia, have been investigated by portable X‐ray fluorescence and by microanalytical methods to identify painting materials (pigments and binders), and to explain the degradation of colours. Today, missing green and blue shades have been reconstructed according to residual concentrations of Cu, which correspond to copper chlorides—products of salt corrosion of the copper carbonates azurite and/or malachite, accelerated by micro‐organisms. As confirmed by powder X‐ray microdiffraction, original minium (Pb3O4) has been transformed to brown–black plattnerite (PbO2). In increased humidity, even insoluble pigments are washing down from the walls and the intensity of colours further diminishes.  相似文献   
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Imperial strategies varied as the Inca expanded their empire from the capital in Cusco. Some communities were conquered violently while others were ruled indirectly with little evidence of Inca presence. According to ethnohistorical evidence, the central coast was peacefully annexed by the Incas ca. A.D. 1470, but little is known about how Inca imperialism may have affected the quality of life of subjects of the Inca Empire. We integrate multiple lines of evidence to assess diet, health and disease for a sample of human remains from the Late Horizon cemetery of Puruchuco-Huaquerones, Peru. Specifically, we examine and analyze osteological, dental and stable isotope data (n = 162, 90 and 46 respectively) in order to investigate whether the Inca period population at Puruchuco-Huaquerones experienced nutritionally insufficient diets and poor health under imperial policies. Diet at Puruchuco-Huaquerones incorporated a variety of foods, both plant and animal. Osteological lesions and stature indicate periods of stress, with males experiencing more illness relative to females. Stature sexual dimorphism, the presence of healed lesions and isotope data indicate a sufficiently nutritious diet and support the conclusion that, although disease was present, individuals were healthy enough to survive and recover. Geographical and temporal comparisons suggest that health changed little with the Inca annexation of this region, but future work is needed.  相似文献   
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In this paper a method for the identification of simplified linear models for building structures is applied to the case when acceleration, rather than displacement, is measured. A frame from benchmark structural controller studies is simulated, and from the input-output data of these simulations, simplified models for the acceleration response of the frame are obtained that have far fewer degrees of freedom. One of these simplified models is used to design a controller, which is tested using an evaluation model from the benchmark controller studies and found to be effective.  相似文献   
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