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This article explores the emergence of collaborative institutional arrangements for managing natural resources in large-scale and complex resource settings, among numerous political jurisdictions and stakeholders. It examines four regional institutions in the United States: the Northwest Power and Conservation Council's Fish and Wildlife Program, the Chesapeake Bay Program, the CALFED Bay-Delta Program, and the Comprehensive Everglades Restoration Plan. While a wealth of literature has looked at the emergence of smaller-scale resource management institutions, and some literature has begun to look at the characteristics and successes of these regional institutions, theory is lacking to explain the formation of these regional institutions. We first introduce three relevant streams of literature—on common pool resources management, on policy entrepreneurs and social capital, and on science and information in policy change—to frame our analysis. The comparisons of the cases point to the importance of integrating key insights from the literature for understanding the formation of collaborative resource governance. We emphasize how science, leadership, and prior organizational experience interact in facilitating institutional change, particularly in the process of raising awareness about resource management problems. In tracing the formation of these institutions, we also identify how external institutional triggers can help spur collaborative governance.  相似文献   
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Journal of World Prehistory - Many societal and environmental changes occurred between the 2nd millennium BC and the middle of the 2nd millennium AD in western Africa. Key amongst these were...  相似文献   
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The use of discriminant function analyses (DFA) in archaeological and related research is on the increase, however many of the assumptions of this method receive a mixed treatment in the literature. Statisticians frequently use complex statistical models to investigate analytical parameters, but such idealised datasets may be hard to relate to “real-life” examples and the literature difficult to assess. Using two faunal datasets that are more typical of archaeological and related research, one comprised of size-corrected linear measurements of bovid humeri and another of 3D geometric morphometric (GMM) shape data of African monkey skulls, and two simulated datasets, we illustrate some of the most important but often ignored issues of DFA. We specifically show why it is paramount to address “over-fitting” by cross-validation when applying this method and how the probability of correctly classifying cases by chance can be properly and explicitly taken into account.  相似文献   
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Ten Early Bronze Age (BzA1, 2200–2000 BC) copper artefacts from the central Valais region from Switzerland were studied for their elemental composition and lead isotope ratios. In order to answer the archaeological question of a local copper supply, a database for copper minerals across the Valais (Switzerland) has been established. This database contains 69 data on lead isotope ratios as well as additional information on the minerals and geochemical associations for copper minerals from 38 locations in the Valais. Comparisons of the artefacts were also made with data pertaining to minerals from various deposits from Europe and Anatolia taken from the literature. The provenance of the materials is very diverse. Some of the data are compatible with the data from the copper mineral deposits of the Valais region. Moreover, three copper lunulae were identified as possibly Tuscan, which suggests contacts between Italy and the Valais region. This pattern also establishes a multiplicity of provenances for the metal and cultural influences in the Alpine environment of the Rhone Valley of Switzerland at the beginning of the Early Bronze Age.  相似文献   
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In 1776, the Sienese botanist Biagio Bartalini (1750-1822) published a catalogue of wild plants growing around Siena, adding an appendix on fossils found in the same area, that is the first monograph on Sienese fossils and one of the first works of its kind in Italy. This paper provides tentative identifications of the species and an analysis of the value and meaning of Bartalini's work. The catalogue reports 72 species, each denoted by a list of names applied to analogous living taxa. Identification of single entities is extremely problematical because it can only be attempted through analysis of the literature, since the original material cannot be traced. The most interesting report is the first record of a Euro-Mediterranean Pliocene species of Sthenorytis (Gastropoda, Epitoniidae). Though important, the catalogue is incomplete, with oversights and mistakes, suggesting little familiarity with the subject. Shortcomings include some inconsistencies in the species sequence, the report of giant clams and the absence of molluscs ubiquitous in the Sienese Pliocene and sharks. Nor is it true that it is the first Italian palaeontological work in which binomial nomenclature was used, as sometimes claimed.  相似文献   
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Based on ethnographic accounts from the eighteenth to the twentieth century, functional areas have been identified within Fueginian shell middens. In this context, archaeological microfacies acquire a functional meaning when the microscopic record is compared to information gathered from ethnology, macroscopic observations made during excavation, and experimental modern analogues. All these lines of evidence were combined for the first time at Tunel VII, an eighteenth/nineteenth century shell midden occupied repeatedly by Yamana people, the last hunter–gatherer–fisher groups of the Beagle Channel. The sampling strategy involved three sets of samples: (1) two stratigraphical columns taken from the hut “entrance” and from a portion of the shell midden (i.e., the surrounding refuse shell ring), (2) thin sections from five hearths representing successive phases of frequentation of the hut, and (3) experimental burnt valves of Mytilus edulis, the main malacological component of the site. Comparison of microfacies from groups (1) and (2) provided microscopic indicators to distinguish between shell dumping areas and occupation surfaces. Comparison of microfacies within columns from group (1) allowed recognizing periods of site abandonment and periods of more intense/longer site frequentation. The experimental samples from M. edulis served as a reference to characterize the five central hearths in terms of maximum burning temperatures reached. Different burning structures were correlated to the season of hut frequentation and to their location (and function) within different portions of the hut. The intra-site micromorphological comparison strategy within a well-documented ethnohistorical context provides valuable indicators for the identification of functional areas in archaeological contexts when ethnographical information is not available.  相似文献   
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