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101.
Excavation of Testar del Molí, the only workshop found in the Manises-Paterna area, revealed the existence of a fourteenth-century ceramic workshop covering the remains of the thirteenth-century workshop. This study is concerned with the fourteenth-century production, and forthcoming papers will connect both epochs following the findings of current excavations. The chemical and mineralogical characterization of the ceramic production of this workshop shows the presence of three groups of ceramic pastes which could also be distinguished by, and, thus, related to, their daily use. The raw materials found in the excavation have also been mineralogically and chemically characterized, and a model of possible mixtures of raw materials has also been developed in order to determine their possible use in the manufacture of the pottery previously characterized. 相似文献
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This paper considers the impact of technology on methods used to classify land potential. With developments in new technologies such as Expert Systems (ES) and Geographic Information Systems (GIS), McKeown (1987) proposes a new method by which to explain the decision making process for land classification to an end user. Consideration is given to McKeowns' concept and the literature reviewing both traditional land classification methods and ES and GIS systems. 相似文献
104.
Ancient mortars from northern Italy, dating from the fifth to the seventeenth century AD, were examined in order to formulate an hypothesis regarding the origin of the white lumps often observed in these mortars and in other samples of the same geographical provenance. Various characterization techniques were employed, including scanning electron microscopy, X-ray powder diffraction and Fourier transform infrared (FTIR) and micro-FTIR spectroscopy. 相似文献
105.
Lead-glazed pottery from the medieval workshop of Les Olleries Majors (Paterna, Spain) has been studied by Mössbauer spectroscopy, X-ray diffraction, X-ray fluorescence and optical spectroscopy. Yellow, brown and honey-coloured glazes occur on pots glazed on only one surface. They have virtually identical compositions and transmittance spectra, their apparent differences in colour are due to the colours of the underlying pastes. Yellow glazes occur on cream-coloured calcareous bodies, honey-coloured glazes occur on less calcareous bodies with some development of hematite, while brown glazes occur on red siliceous cooking-pots. Green glazes are found on pots glazed on both surfaces; the glazes trapped CO2 evolved by decomposing carbonates, resulting in an internal reducing environment. This caused the reduction of iron to the ferrous state which coloured the glaze green by diffusion. 相似文献
106.
SPATIAL DEPENDENCY OF SEGREGATION INDICES 总被引:3,自引:0,他引:3
David W.S. Wong 《The Canadian geographer》1997,41(2):128-136
A few researchers have mentioned the scale sensitivity of segregation index, D. In this paper, I discuss analytically and empirically why using large enumeration areal units usually results in low segregation measures, and using small areal units produces relatively high segregation measures. The discussion is also applicable to the multi-group variant of D. A major finding is that if people of the same ethnic groups are positively spatially auto-correlated, increasing the size of areal units of analysis may not lower D initially, because only people of the same group are added. But enlarging the areal units subsequently may include population of other ethnic groups, and therefore could lower D. However, if the boundaries of the larger enumeration units are drawn to include only population of the same group, then D will not change significantly. Both the spatial autocorrelation of ethnic group population and zonal pattern are critical factors in determining the scale sensitivity of D. 相似文献
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