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1.
The grounds of 51 post‐Byzantine icons (Eastern Orthodox panel paintings) were studied by means of analytical techniques. The artefacts cover the period from the mid‐15th to the mid‐19th century and originate mainly from western (Epirus and the Ionian Islands) and southern Greece (Crete). The findings are examined in the light of technical recipes from related areas and eras, while special insights are gained from the exploration of a gypsum processing recipe by Dionysius of Fourna. A spectrum of ground fabrication practices that is richer than that reported so far or can be deduced from surviving Greek recipes is documented; three instances of ‘grosso‐sottile’ type grounds and a case of ‘inverse grosso‐sottile’ ground are among the reported novel, for post‐Byzantine icons, findings. Moreover, a case of an early icon restoration intervention is documented.  相似文献   
2.
This introduction to the translation of Henri Lefebvre's 1956 essay “The theory of ground rent and rural Sociology” moves through three stages. First, it suggests that Anglophone appropriations of Lefebvre have tended to focus too much on his urban writings, at the expense of understanding his early work on rural sociology, and failing to recognise how his urban focus emerged as a result of his interest in rural–urban transformation. Second, it provides a summary of his wider work on rural questions, including his unfinished work on a major treatise of rural sociology; and outlines the key themes of the present essay in relation to these other projects. Third, it connects Lefebvre's issues to wider debates in political economy and geography about aspects of the rural, land and ground rent, not least including the work of Antonio Gramsci and José Carlos Mariátegui.  相似文献   
3.
本文探讨了有关唐代越窑青瓷刻划花的若干问题。作者以有明确纪年的唐代越窑刻划花青瓷以及相关的同一时期的有代表性的墓葬、窑址、遗址、沉船中发现的越窑刻划花青瓷为依据,总结了唐代此类瓷器工艺的演变规律和技法特征,分析了其与金银器的关系问题,并推测出此类瓷属于对外贸易的外销产品。  相似文献   
4.
To help improve the well‐being of the local people, a joint Vietnamese‐UK team set out to establish a way of estimating soil and nutrient losses under different land management scenarios, using field data extrapolated through remote sensing and GIS, to obtain catchment‐wide estimates of the impact of land cover change. Immigration from remote provinces to the Dong Phu District of Binh Phuóc Province, about 120 km north of Ho Chi Minh City, has led to disruption of soil surface stability on easily eroded clayey sandstones, creating rapid nutrient depletion that affects crop yields and siltation in the channel of the Rach Rat river downstream. The poor farmers of the areas see crop yields drop dramatically after two or three years of cultivation due to the fertility decline. Soil loss varies dramatically between wet season and dry season and with ground cover. Erosion bridge measurements showed a mean loss of 85.2 t ha?1 y?1 under cassava saplings with cashew nuts, 43.3 t ha?1 y?1 on uncultivated land and 41.7 t ha?1 y?1 under mature cassava. The rates of erosion were higher than those reported in many other parts of Vietnam, reflecting the high erodibility of the friable sandy soils on the steep side‐slopes of the Rach Rat catchment. However, although the actual measurements provide better soil loss data than estimates based on the parameters of soil loss equations, a large number of measurement sites is needed to provide adequate coverage of the crop and slope combinations in this dissected terrain for good prediction using GIS and remote sensing.  相似文献   
5.
通过对上海及邻近地区地震危害性分析,结合地震研究工作结果,根据上海博物馆文物防震保护的具体要求,研究确定了该博物馆文物防震保护的设防水准及地震动参数。场地地震动输入峰值加速度水准确定为50年超越概率3%,地震动反应谱采用上海市标准《建筑抗震设计规范》(DGJ08-9-92)中给出的地震影响系数曲线(阻尼比0.05),并将输入峰值加速度调整为180gal。研究采用了目前通用的拟合反应谱的方法,通过拟合选定的地震动反应标准谱,合成了6条人造地震波时程曲线,拟合精度控制在相对误差不大于5%;同时结合上海市《建筑抗震设计规范》(DGJ08-9-92)中所附的一条强震记录,共同作为上海博物馆结构地震反应分析的输入地震动。又根据上海博物馆建筑的结构特征分析,结合建筑结沟动力特征的实测结果,通过采用层模型结构时程分析计算方法,计算并获得了在遭遇设防地震时,上海博物馆建筑物每一层的地震动反应,表明上海博物馆建筑各楼层的地震动反应具有明显的楼层放大作用。对各楼层地震动反应的统计分析,给出了上海博物馆建筑物每一层的地震动参数,以此可作为今后文物地震危害性分析,及研究设计隔震装置等防震措施的依据。  相似文献   
6.
One of the cutting-edge topics being currently debated in social sciences is the impact of financialization on corporations and on different geographical contexts. Surprisingly enough, there have been very few studies that have explicitly dealt with this issue within tourism studies. In this paper, the issue of financialization within tourism is addressed through an analysis of hotel corporations. Taking a case-study approach, it is argued that Spanish hotel chains are increasingly becoming financialized since a minimization of the impact of global financial crisis on these corporations is urgently required. The argument is not that hotel corporations’ financialization is necessarily new, but rather that the impact of the global financial crisis has led to an intensification of this very process. Taking as case studies the three largest Spanish hotel corporations (Meliá Hotels International, NH Hoteles and Grupo Barceló), the current crisis-led hotel financialization is dealt through four interrelated spheres: (1) built environment (hotel buildings property becoming controlled by financial funds), (2) actors (emergence of new agents as a result of hotel corporations intertwining with financial corporations), (3) hotel profit extraction (reliance on the secondary circuit of capital), (4) financial engineering instruments (forms of fictitious capital that are new in the context of hotel corporations). The article shows how the process of financialization of hotel corporations illustrates broad trends of both financialization and capital accumulation. Specifically, the main findings are on one hand, that financialization not only fixes capital on the ground, but also creates liquidity. On the other hand, that the selling of property titles is an increasing profit niche with differentiated geographical locations. The last significant finding is that financialization helps to improve profitability of non-financia corporations such as hotel chains.  相似文献   
7.
In Turkey, with the occurrence of almost every strong and even moderate earthquake, damage to masonry minarets is observed. In the present work, efficiency of vertical post-tensioning application to reinforce masonry minarets against earthquakes has been investigated. Considering a representative minaret and its post-tensioned counterpart, and performing spectral and time-history analyses, the effects of post-tensioning on the axial stresses, top lateral displacements and overturning safety have been determined. Obtained results have shown that vertical post-tensioning application is a very efficient method to reduce axial tensile stresses and lateral displacements, and to assure the overturning safety of masonry minarets against earthquakes.  相似文献   
8.
We present a scheme to modify empirical Green's functions by attenuation considering: (1) geometrical spreading; (2) decay in high frequency; (3) regional attenuation; and (4) phase of the signal. The accelerograms computed with the proposed simulation method are compared, in time and frequency domains, with strong ground motions from subduction and intermediate-depth earthquakes recorded in Mexico. It is shown that this simple empirical Green's functions technique can synthesize both the shape and amplitude of the response spectra in the site, considering a postulated seismic source located at different distances from the original one.  相似文献   
9.
This article describes seismic hazards, including fault rupture, liquefaction, landslides, and site amplification, using Los Angeles as a case study. Water supply simulation results are presented for a 7.8 MW earthquake on the San Andreas Fault. Severe water losses are shown after 24 h, with nearly 2,700 locations of pipeline damage and a 66% decrease in normal water service. The water supply system was modeled with and without reservoirs that have been removed from service to meet water quality standards. The results show that opening the disconnected reservoirs immediately after a serious earthquake is an effective strategy for emergency response.  相似文献   
10.
In this study, M5′ model tree is used to develop a model for prediction of peak time-domain strong ground motion parameters. The main advantages of model trees are that can be easily developed and their formulas are simple and understandable. Selected data from Pacific Earthquake Engineering Research Center (PEER) are used to train the proposed model. Earthquake magnitude, earthquake source to site distance, average shear-wave velocity, and faulting mechanisms are used as input parameters. The developed M5′ based formulas are compared with those of well-known empirical and soft computing based models. The accuracy of the model is evaluated by statistical error parameters.  相似文献   
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