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991.
Since the 1960s the analysis of small-scale surface processes has been the dominant approach in geomorphology, the previous focus on regional-scale landscape evolution having been largely abandoned as a result of the lack of knowledge of processes and process rates at the relevant temporal and spatial scales. It has recently been acknowledged that small-scale, surface process geomorphology alone is unable to provide an understanding of long-term landscape development, both because of the significance of tectonics, and because of the important role of contingency at the large temporal and spatial scales involved. But the major advances in geochronological techniques and numerical modelling of landscape evolution that are now revolutionizing our understanding of long-standing questions of landscape evolution have been largely developed and applied by researchers from outside the traditional geomorphology community. As a result, two distinct communities of researchers have emerged concerned with different scales of landform analysis, but the progress of geomorphology will be best served by greater interaction between them. 相似文献
992.
993.
994.
THE ORIENTATION OF ROMAN CAMPS AND FORTS 总被引:1,自引:1,他引:0
A. RICHARDSON 《Oxford Journal of Archaeology》2005,24(4):415-426
Summary. The angles of orientation of 67 Roman camps were determined from their published plans. There was a marked tendency for them to be aligned close to the cardinal points but they were offset from those points by only 28 of a possible 45 angles and of these six occurred in 29 camps, probably because they were set out by making right-angled triangles whose non-hypotenuse sides were in whole number ratios. Twenty-seven forts on the British frontier walls were similarly orientated by only 12 angles, one of which occurred six times. The apparent accuracy of the layouts suggested that the directions of the meridian and latitude were first carefully determined. The use of a limited number of offset angles was probably due to a religious regard for celestial geometry. 相似文献
995.
E. Gliozzo D. D’Aco I. Memmi Turbanti A. Galli M. Martini E. Sibilia 《Archaeological and Anthropological Sciences》2009,1(2):77-85
Twenty-one samples of likely Roman, likely Islamic and unknown common ware from the archaeological site of Thamusida (Rabat, Morocco) were analysed in order to anchor selected types of pottery to a limited time span and, possibly, to a production
area and technology. Analytical techniques were thermoluminescence, optical microscopy, scanning electron microscopy and X-ray
fluorescence. The results arising from this research are definitely useful for the study of the site of Thamusida as well as for all researchers involved in archaeological and archaeometrical research in Morocco. Chronologies proposed
on a typological base have been denied twice: a likely Islamic cup dates back to the second century a.d.; vice versa, a stewpot, framed into the Roman period, resulted to be an eighth century a.d. production. Moreover, the identification of an eighteenth century ceramic production is of outstanding importance, as it
characterises a completely unknown production. Regarding the production area, four samples of both Roman and Islamic periods
have been recognised as local productions of Thamusida. 相似文献
996.
A. CRISTINA DE LA VEGA‐LEINERT SUSANNE STOLL‐KLEEMANN TIM O'RIORDAN 《Geographical Research》2009,47(4):351-361
This paper makes the case for advancing sustainability science partnerships (SSPs) both within universities and through innovative means of integrating universities with external public‐private and civil sectors. It links the basic principles of sustainable development with an emerging science of cooperative learning that connects researchers to a wide range of partners. SSPs are specifically designed to be transformational through becoming active agents for societal change. Universities play a special role here because they can act both as communication networks and as laboratories for developing the capability to design and manage SSPs in the creative transition to sustainability. It is gratifying to note that these ideas are beginning to emerge in a number of universities, with European examples being highlighted in this paper. Further steps towards introducing full‐blooded SSPs across the university spectrum are suggested. 相似文献
997.
Fragments of late medieval highly decorated Falke‐group stoneware have been found in excavations all over central and northern Europe. The distribution of the finds points to an origin in Saxony, but the exact centre of production is still unknown. Therefore, a set of samples has been analysed with Neutron Activation and the data compared with Saxon reference groups. The results point to production in a single workshop. The data can be clearly distinguished from all reference groups in our databank. However, the most similar group is that of Zittau, Saxony. Also, one sherd, which is typologically very similar to the Falke group, and which was made in Zittau, suggests that production was based there. 相似文献
998.
Previously published data on the chemical compositions and microstructures of copper‐ and cobalt‐blue frit, glass and faience from the New Kingdom site of Amarna in Egypt ( Shortland 2000 ) are summarized. The data are then used to infer the raw materials and processes employed in the production of these vitreous materials. The results suggest that crushed quartz pebbles were the source of the quartz for all the materials, but that different sources of alkali, both natron and a range of plant ashes, were used in the production of each material. It seems probable that the cobalt‐rich alum colorant was pre‐treated before use by precipitating cobalt hydroxide from a solution of the alum by the addition of natron. It is further hypothesized that cobalt‐blue glass was produced by melting the cobalt‐blue frit together with additional plant ash and possibly quartz. Finally, it is suggested that, in glazing the cobalt‐blue Variant D faience first produced in the 18th Dynasty, the efflorescence or application method was selected according to object type. 相似文献
999.
A group of Italian glazed terracotta sculptures, attributed to the della Robbia workshop of Florence, is partly displayed in the Louvre Museum. Analyses of the apparently homogeneous sculptures by techniques such as PIXE, SEM, ICP/AES and ICP/MS have identified differences in the materials used. The data provide a subdivision of the sculptures, which is compatible with what is known from historical documents and artistic considerations, and suggest a date for this ensemble at the end of the 15th century, when the della Robbia family was involved in the decoration of the San Frediano church in Florence. 相似文献
1000.
Peter M. Atkinson Sally E. German David A. Sear Michael J. Clark 《Geographical analysis》2003,35(1):58-82
The relations between riverbank erosion and geomorphological variables that are thought to control or influence erosion are commonly modelled using regression. For a given river, a single regression model might befitted to data on erosion and its geomorphological controls obtained along the river's length. However, it is likely that the influence of some variables may vary with geographical location (i.e., distance upstream). For this reason, the spatially stationary regression model should be replaced with a non‐stationary equivalent. Geographically weighted regression (GWR) is a suitable choice. In this paper, GWR is extended to predict the binary presence or absence of erosion via the logistic model. This extended model was applied to data obtained from historical archives and a spatially intensive field survey of a length of 42 km of the Afon Dyfi in West Wales. The model parameters and the residual deviance of the model varied greatly with distance upstream. The practical implication of the result is that different management practices should be implemented at different locations along the river. Thus, the approach presented allowed inference of spatially varying management practice as a consequence of spatially varying geomorphological process. 相似文献