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21.
奥里诺科河是亚马逊河上一条光涌的逆流,更是一段有关虔诚的传教士和印第安土著人的古老故事。  相似文献   
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Lithic debris derived from knapping and used tools can be assimilated to simple sedimentary particles that may undergo size sorting when exposed to geomorphic processes such as streamflow or overland flow. Sorting can be identified by comparing the size distribution of archaeological assemblages to that of experimental core reduction sequences. A new database including different types of raw material (mainly flint and quartzite) and Palaeolithic debitage (blade, Levallois, discoid, on anvil, and shaping) has been built for this purpose. Palaeoeskimo data have also been added to illustrate microlithic industries. For all the debitages and raw materials, the particle size of knapping products >2 mm in width fits with a power-law distribution and shows only minor fluctuations, the range of which is always <15% between experiments (all steps of the chaîne opératoire included up to the final tool). A lithic assemblage derived from block/core knapping or blank/preform production will display a particle size distribution close to the experimental distributions if not subsequently modified. Modifications may originate either from sedimentary processes or from anthropogenic factors. To help distinguishing amongst these, data on the impact of both water flows on sedimentary particles or experimental assemblages, and anthropogenic processes such as importation-exportation (of core, preforms or finished tools) or uneven spatial distribution of the different steps in core reduction and tool production within a site, are reviewed. By contrast to anthropogenic modifications, sedimentary processes are generally typified by strong impoverishment in or selective accumulation of fine-grained (<10 mm) artefacts together with a low intra-site variability (spatial homogenization) or a downslope size trend. Archaeological case studies taken from French Palaeolithic site are then detailed. Evidence for lithic redistribution implies that care should be taken in archaeological site analysis since sorting may impact significantly the initial techno-typological balance of the assemblage.  相似文献   
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This article looks at the reconfiguration of the regulatory actors' network, as induced by the liberalization and reregulation processes in utility sectors. It investigates the changes in governance structures and patterns of collaborative ties between actors resulting from these processes. Applying stochastic actor‐oriented modeling (SAOM) to data on the liberalization of the Swiss telecommunications sector over two decades, we test whether and to what extent structural changes driven by liberalization and reregulation express themselves through network effects, that is, through changing patterns of interactions between political authorities, regulators, regulatees, and interest groups. Our empirical tests highlight a rearrangement of the regulatory network and a reorganization of relational patterns around new actors, such as the sector‐specific regulatory agency, coregulators, and new operators.  相似文献   
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This paper presents the results of an experimental study into the usefulness of X-ray florescence (XRF) in identifying the composition of metal artifacts found at aboriginal sites in northwestern Ohio. In the late 1990s, we subjected 96 samples to XRF and documented our results. We then compared our data to that collected by more precise spectrographic methods to assess the effectiveness of the XRF method for this application. While not precise enough to source native coppers, we conclude that XRF is a cheap, nondestructive method for differentiating native copper from its European counterparts at sixteenth- and seventeenth-century Late Woodland sites.  相似文献   
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This paper compares and contrasts the instruments and values formulated in the creative industries policies of three peripheral municipalities of between 150,000 and 220,000 inhabitants in the Netherlands (Groningen, Arnhem and Eindhoven) with the needs of the creative industries itself. The needs of the creative industries have been empirically researched by conducting an online survey (n = 556) and twelve in-depth interviews with professionals from different types of organizations in the creative industries. In this study, the theoretical framework of Boltanski, Thévenot and Chiapello is used in the analysis of policy documents, the outcomes of the online survey, and the in-depth interviews in order to uncover differences and similarities in perspectives from which art organizations, creative organizations and policymakers are acting in the creative industries.  相似文献   
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Determination of sex is a key aspect in the study of past populations. Bias in skeletal sexing is well known, however, and depends upon the completeness of the skeletal remains and the representativeness of reference samples. In order to correct these difficulties, the authors propose practical adjustments to Van Vark's well‐known procedure. Two fundamental aspects are considered to reduce the bias of sex allocation. First, we propose to increase the effectiveness of sexing during the first step (primary diagnosis only from the pelvic bone). Second, to improve the final step (secondary diagnosis from the extra‐pelvic skeleton), we consider posterior probabilities as essential. These two practical adjustments are successfully tested in a sample of known sex and lead to a classification with 94.5% accuracy. These results significantly improve sex determination in archaeological samples and therefore contribute to a better understanding of past populations. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   
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In this paper, we develop a model of spatial segregation mediated by competitive land prices. Agents of two groups consume city land and benefit from social interactions. Because of cultural or ethnic differences, intragroup interactions are more frequent than intergroup ones. When group sizes differ, population groups sort into distinct neighborhoods. We characterize two‐ and three‐district urban structures. For high population ratios or strong intergroup interactions, only a three‐district city exists. In other cases, multiplicity of equilibria arises. Both groups generally rank these equilibria differently. However, when group sizes are similar, all individuals agree on which spatial equilibrium is best.  相似文献   
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