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21.
The colluvial soils of Galicia (NW Spain) are records of Holocene environmental change. In spite of the omnipresence of charcoal fragments in these soils, the effect of fires on the development of the Galician landscape and the potential role of past societies are poorly understood.  相似文献   
22.
Although there is a considerable amount of empirical evidence on inter-firm collaborations within technology-based industries, there are only a few works focussing on R&D cooperation by low-tech firms, especially small and medium-sized enterprises (SMEs). Providing further and new evidence based on a recently built database of CRAFT projects, this study analyses the relationship between technology and proximity in international R&D networks using HOMALS and statistical cluster techniques. The resulting typology of international cooperative R&D projects highlights that successful international cooperative R&D projects are both culturally/geographically closer and distant. Moreover, and quite interestingly, geographically distant projects are technologically more advanced whereas those located near each other are essentially low-tech. Such evidence is likely to reflect the tacit-codified knowledge debate boosted recently by the information and communication technology (ICT) “revolution” emphasized by the prophets of the “Death of Distance” and the “End of Geography”.  相似文献   
23.
Over more than a century, several proposals have been made on the composition and technical features of the pictorial recipes used by Levantine prehistoric painters. In this paper all these proposals are surveyed and tested through systematic experiments to determine the technical affordance of pigments and binders in different pictorial recipes. Experimental results were then used as independent analytical parameters employed as diagnostic criteria to systematically study an archaeological sample of nine sites located in the Maestrazgo region (Spain) and their surroundings. Results reveal that out of 112 experimental recipes, only 16 afforded the production of paintings technically similar to Levantine rock art.  相似文献   
24.
Blue‐on‐blue (‘berettino’) sherds have appeared in numerous production and consumption archaeological excavations in Lisbon and other archaeological sites in Portugal (dated from the mid‐16th century to the beginning of the 17th century). The abundance of this interesting faience led us to compare it with similar pottery from other well‐known production centres in Italy, namely Liguria (Savona and Albisola), Spain (the Triana kilns) and the Low Countries. Differences in the diffraction patterns of the sherds' pastes from the four countries were observed. In most samples, cobalt blue silicate (cobalt olivine) was identified in the dark blue or light blue glazes through the use of micro‐Raman spectroscopy and diffuse reflectance spectra. A remarkable difference in the calcite contents of the Lisbon and Seville pottery sherds was observed, in accordance with previous observations of high calcite contents of Seville ceramics. A comparison was also made for all of the blue‐on‐blue sherds studied here with many other 16th–17th century sherds from Lisbon using bivariate plots of K/Si versus Ca/Si. Lisbon and Seville pottery behave very differently, whereas sherds from Italy and the Low Countries occupy intermediate positions.  相似文献   
25.
At the turn of the twentieth century, private grain exchanges settled the daily prices for North American wheat. By the end of the Second World War, the Canadian and US governments had intervened significantly in these markets. The Canadian government required farmers in its western provinces to deliver their product to the Canadian Wheat Board (CWB), a single-selling-desk agency that, by then, had supplanted private wheat marketing in western Canada. Meanwhile, the United States government subsidized farm incomes with domestic-use taxes and import tariffs, but otherwise preserved private wheat marketing. In this article, I demonstrate that these disparate agricultural policies were broadly defined by immutable economic realities imposed on each country by global wheat-trade patterns and triggered by unprecedentedly severe agricultural crises. That is, amidst the precipitous fall in wheat prices in the early 1930s, each government crafted farm-support policies that reflected its domestic-consumption share of wheat production and the importance of wheat to its overall economy.  相似文献   
26.
Lithic assemblages recovered from sites located in the eastern Pampa–Patagonia transition include a great diversity of raw materials, some from neighbouring regions, such as the Humid and Dry Pampa subregions and Northpatagonia. Lithic raw material assignments to specific procurement areas were preliminarily proposed based on macroscopic characterizations. The aim of the paper is to present the results obtained from the petrographic thin sections of archaeological artefacts from Middle and Late Holocene sites recorded at the study area. The analyses corroborate most of the macroscopic determinations, and more detailed knowledge of the acquisition areas of these raw materials was obtained.  相似文献   
27.
In this article, GPR – Ground Penetrating Radar and inductive electromagnetic (EM38 equipment) results are presented for three archaeological sites of shell mounds located between Laguna and Jaguaruna cities, mid-southern coast of Santa Catarina state, Brazil. The Jabuticabeira II, Santa Marta IV, and Encantada III sites were studied. These sites consist of carbonate shell mounds built by societies that inhabited this region during the pre-colonial period (7.5–1.3 ky BP). Geophysical responses obtained in these archaeological sites had allowed the identification of anomalous regions related to archaeological point targets as well as continuous targets, correlated to the shell mound's structure and buried geologic features. GPR numerical modelling studies were done in order to evaluate the performance of the GPR method in relation to materials found in that environment, besides helping interpretations of real results. The synthetic GPR model was a good match with real data obtained in the field. So, the real and synthetic results serve as a reference guide to direct excavation activities in these archaeological and geological structures. In the Jabuticabeira II shell mound, lithic materials and burials were found amidst archaeological layers characterized by sediment rich in organic material, ferruginous concretions, and loose shells. In the Santa Marta IV archaeological site, a concentration of ceramic materials, burials and fireplaces were found. In the Encantada III site, a strong anomaly characterized by a hyperbolic reflection was related to the presence of a silicified tree root; a great example of ambiguity in shallow geophysics interpretation in archaeological applications. Results functioned as a guide to archaeological excavations, allowing cost and time reduction as well as contributing to improve the knowledge of these archaeological sites situated in southern Brazil.  相似文献   
28.
We present results of electrical conductivity profiles obtained with inductive electromagnetic geophysical method in Santa Marta archaeological site, Santa Catarina State, southern Brazil. This site is a sambaqui (shell mound), in which several human occupation remains are found during pre-colonial period such as buried lithic and bone artifacts, fire-place, etc. Most of these mounds include as well many human burials, which, in many cases, point to funerary ritual as a main agency for mound building. A set of profiles of apparent electrical conductivity and magnetic susceptibility was acquired in two sites aiming the identification of geophysical anomalies with potential interest for excavation. To enhance conductivity data, we applied an effective procedure to remove topographical effects in the apparent conductivity measurements, which are rather conditioned by the presence of a variable water table depth or conductive sediment layer. A linear dependence among conductivity values and the site elevation provided a simple linear model to remove the influence of topography. Corrected electric conductivity maps substantially improved the definition of anomalies, many of them rather subtle in raw data images. Corrected maps also show a better adherence with magnetic susceptibility maps, both of them identifying archaeological structures of interest: a well-structured fire-place and a concentration of ceramic fragments.  相似文献   
29.
30.
In the present study the author examines the migratory practices of movement between France and Portugal of young French of Portuguese ancestry, as well as of young Portuguese living in France. The study of these practices from an ethnological point of view sheds light on the interaction of material resources and the multifaceted symbolic resources associated with them. Besides the economic and political dimension in which these practices are grounded, the identity — forming process of which they are a part raises a number of questions — especially in the context of the European Union. The author shows how, by using elements drawn from the family migratory history, natural history and Portuguese culture, the descendents of Europeans who migrated for economic reasons are now trying to go beyond the dilemma of an identity posed by their «double culture», as well as the social and cultural constraints imposed on them by their elders.  相似文献   
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