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For several decades, a growing number of protohistoric sites in Auvergne (Massif Central, France)—mostly excavated through preventive archaeology—have been subject to the collection of archaeobotanical analysis. This study presents the archaeobotanical results from ten La Tène sites dating from the last five centuries before the Roman conquest. In addition to providing an inventory of taxa, this paper concerns crops and crop cultivation methods. These results are interpreted in a wider context, dealing with crop husbandry, arable farming, storage and consumption practices. The sites are located in the Limagne plain within a 50-km radius around the city of Clermont-Ferrand. A total of 23,579 carpological remains were identified from 163 sediment samples totalizing a volume of 1096 l. Comparable to other sites in Gaul, the spectrum of cereals and pulses is restricted. Spelt (Triticum spelta), einkorn (Triticum monococcum) and foxtail millet (Setaria italica) are disappearing or becoming rare. A better control of agricultural techniques and increased yields is supposed during the ca. five centuries of the La Tène period. Mixed cultivation is hereby replaced by the sowing of monocrops. At the beginning of this period, farming systems are dominated by a polyculture of cereals and pulses. They become more specialized during the last two centuries before the Roman conquest; diversity of cereals and pulses is decreased.  相似文献   
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Des comparaisons entre villes canadiennes et américaines doivent se faire avec prudence. L'obstacle principal reste la comparabilité des séries statistiques. Nous proposons une analyse intégrée de l'ensemble des 90 régions métropolitaines nord-américaines de 500 000 habitants et plus, dont neuf canadiennes. Suite à une revue de divers classements, nous situons les 90 régions urbaines sur sept indicateurs, dont des variables portant sur le capital humain et le secteur tertiaire intensif en savoir, suivi d'une analyse de corrélation mettant en relation les indicateurs pour trois univers de villes (sans et avec des villes canadiennes). Nos résultats confirment le bon positionnement sur plusieurs indicateurs de métropoles américaines comme San Francisco-Silicon Valley et Boston, mais aussi de villes comme Raleigh (research triangle) et Austin, connues pour leurs activités de recherche. Les villes canadiennes se classent plutôt bien, notamment les cinq plus grandes. Cependant, c'est moins vrai pour des villes comme Winnipeg ou Hamilton. L'analyse de corrélation fait ressortir la relation positive entre dotation en capital humain et poids du tertiaire intensif en savoir, mais ne révèle aucune relation significative avec l'indicateur de qualité de vie.  相似文献   
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A period-independent approach for the selection and scaling of ground motion records aimed at reducing demand variability is proposed for seismic response history analysis. The same set of scaled records can be used to study various structures at the same site regardless of their dynamic characteristics. The statistical robustness of the proposed and current approaches is compared through nonlinear inelastic dynamic analyses performed on single-degree-of-freedom systems and multi-story braced frames. The proposed approach leads to consistent response predictions with a limited number of records. This is advantageous for day-to-day structural design or assessment against code hazard-based seismic demand levels.  相似文献   
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This study presents a new method to measure the depth of ancestral roots in a population. This method sheds light on the migratory movements that led to present-day population distribution across space. The method was applied to a dataset of 5,100 ascending genealogies from 17 regions of the province of Quebec (Canada). Dates of marriage of the earliest ancestors married in the same region as their descendants were used to measure the age of individual ancestral roots. The average regional ages vary between 16 and 157 years, while some individual roots reach as far back as 300 years in the same region. The proposed method can be useful for assessing how deeply rooted a contemporary population is at a local, regional, or other geographical level.  相似文献   
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ABSTRACT

The site of Huanchaquito-Las Llamas, situated in the Moche Valley, Peru, dated to the Late Intermediate Period (AD 1100-1470), represents a single event mass killing of children and domestic camelids of the Chimu society. Reconstruction of the life histories of 82 camelid individuals based on stable isotope analysis of bone collagen indicates that they originated from the lowlands. Isotopic inter-individual variability indicates diversity in dietary sources, consisting of wild plants and cultigens, grown in water-limited and non-water-limited conditions, as well as a large proportion of C4 plants, suggesting that the animals originated from various herds that were differently managed. In contrast, uniformity in terms of restricted coat colour and young age could suggest that the animals derived from specialised herds. It is possible that the requirement in a short period of time for a massive number of animals meeting certain criteria exceeded the capacity of these herds. This study presents the largest isotopic dataset measured at a single pre-Hispanic site so far and the first to record herding practices for the Chimú society. Comparison with previous isotopic datasets shows differences between ritual and non-ritual groups, as well as diversity in pastoralism practises through time in the Central Andes.  相似文献   
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