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91.
In early Roman times, iron was likely supplied to the city of Sagalassos through the smelting of close-by hematite ores. In the early Byzantine period, magnetite–titanite placer sands in some instances could have been exploited for its iron. For the intermediate late Roman period, however, the source of the locally used iron was unknown. Pb and Sr isotopic analyses of iron ores from the area of Camoluk, just south of the territory of Sagalassos, and of late Roman iron artefacts from the antique city itself, reveal a very close resemblance. This makes the use of the Camoluk ores to supply Sagalassos with raw iron in the late Roman period likely. It is also shown that combined Pb and Sr isotopic analyses provides a powerful tool to distinguish chronological groups of iron provenance and a technique that can determine the nature and source of iron raw materials used.  相似文献   
92.
The strontium isotope ratio (87Sr/86Sr) is used in archaeological studies to identify major events of population movement in prehistory such as migration, conquest, and inter-marriage. This study shows that the strontium isotope method can be expanded to identify more subtle shifts in prehistoric human mobility. 87Sr/86Sr isotope ratios were analyzed in dental enamel from human and faunal specimens from the Late Neolithic and Copper Age on the Great Hungarian Plain. The archaeological record indicates that several aspects of life changed during the transition from the Late Neolithic to the Copper Age (ca. 4500 BC) in Hungary; evidence for increased interaction over a wide geographical area, less resource pooling and the use of secondary products has been used to support the idea that local populations became more mobile, perhaps due to the adoption of an agro-pastoral economy. Results from this study identify a change in the range of strontium isotope values from the Late Neolithic to the Copper Age from a very narrow range of values to a much broader range of values, which suggests that changes in how land and resources were utilized on the Great Hungarian Plain affected incorporation of strontium into the skeletal system. This study indicates that the strontium isotope ratio is a valuable tool for identifying more subtle changes in prehistoric behavior such as a shift to a more pastoral economy.  相似文献   
93.
The paper tests the hypothesis that innovation activity determines the growth prospects of small low-tech firms. Innovation here is analysed as a function of a firm's knowledge base and the relational proximity processes it is involved in. Analysis refers to small and medium- sized enterprises in tourism under the premise that important insights might be provided as regards to the functioning of innovation processes in low-tech industries.  相似文献   
94.
Surface networks capture the topological relations between passes of a continuous surface, the paths of steepest descent and ascent starting at the passes, and the pits and peaks where the steepest paths end. Surface networks represent the topology of surfaces in a compressed form and allow fast investigation of the surfaces' convex and concave shapes. They are applied, for instance, for enhancing algorithms for surface analysis, for surface model simplification, and for surfaces visualization. Furthermore, they are themselves subjects of analysis as they are closely coupled to the intrinsic geometrical concepts and rules of continuous surfaces.
This article extends the topology of surface networks in four ways: (i) objects at the edge of the surface model are introduced; (ii) intersections between valley and ridge lines are found to be possible, and such intersections are incorporated into the topology; (iii) horizontal areas may represent passes, pits, or peaks, and therefore must be detected and explicitly incorporated; and (iv) valley and ridge line hierarchies are recognized as inherent components of the surface network. They are extracted and explicitly represented.
To ensure consistency and completeness of the surface network, a zero-order continuous surface is specified from the raster data prior to the extraction. This article presents a method to represent and derive valley and ridge line hierarchies. The results are illustrated with two examples. The extracted networks are found to be consistent and complete. However, the extraction method tends to produce spurious pits, peaks, and passes, which form a drawback if the surface data are affected by noise.  相似文献   
95.
96.
The secondary production (working) of glass from imperial to early Byzantine times has been proven at the ancient city of Sagalassos (SW Turkey) by the existence of glass chunks, fuel ash slag and kiln fragments related to glass processing. It had been previously suggested that local green glass might have been recycled from two other locally found glass types (blue glass vessels and chunks and HIMT glass chunks). This paper provides analytical evidence for the recycling of glass next to the use of imported raw glass. The heterogeneous lead isotopic composition of the green and HIMT vessel glass at Sagalassos, with as end members on the one hand the isotopic composition of local blue glass vessels and chunks and on the other hand that of the HIMT glass chunks, could indicate the production of ‘recycled’ glass, although heterogeneous raw materials could have been used. However, the use of Sr-mixing lines confirms local recycling. It is clear that the Sr in the green and HIMT vessels is a mixture of the Sr in the aforementioned end members. It cannot be proved whether the green ‘recycled’ glass was produced from a mixture of chunks alone, or from a mixture of cullet and chunks. Suggestions are made towards the possible origin of the raw materials for the blue and HIMT glass on the basis of Sr isotopic signatures and absolute Sr contents in the glass.  相似文献   
97.
98.
This paper discusses the out of school routines of a group of ‘literature-devoted’ children of the city of Madrid (Spain). The children and families were recruited for the study at a library, a children's bookstore and a puppet show in a park. Participants provided information on their weekly routines through several procedures: surveys, photographs of their daily lives, interviews based on the photographs and interviews with parents. We develop a spatially based model that allows us to identify four styles of activity in children's out of school lives: homebound children, non-scheduled children, outdoor and scheduled children, and fully scheduled children. Our results suggest that there is significant diversity in the ways in which children's after-school time is organized, even within a middle-class and socially homogeneous sample as the one in this study. Also, the range of activities our participants engage in seems to contradict current portraits of Western urban children's lives as constrained.  相似文献   
99.
This essay explores the ways in which strategies of commemoration elaborated by kin groups changed after the end of the western Roman empire and what role Christianity played in these transformations. In order to shed some light on the situation, a broad sample of cemeteries dating from late antiquity and the early Middle Ages was analysed, focusing on the spatial organization of the individuals within the cemeteries and around cult places. For this purpose archaeological, physical anthropological and epigraphic data were studied and juxtaposed with the theoretical debates expressed by Christian writers. The data at hand seem to suggest that rather than radically transforming kinship commemoration strategies, Christianity added new ideological layers, making its use and display multidimensional.  相似文献   
100.
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