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331.
A data-based procedure is presented to develop spectra-compatible time-history records that are based on the dominant probabilistic features of an ensemble of records corresponding to the non-stationary stochastic phenomena of interest (e.g., earthquakes, wind loads, etc). The method requires a statistically significant collection of time-history records that are used to construct the associated covariance kernel of the random process. Subsequently, orthogonal decomposition approaches are used to determine the dominant eigenvectors of the covariance matrix, and these vectors are then linearly combined, with an adjustable amplitude-scale and phase-shift, to determine, via a nonlinear optimization scheme (employing a combination of stochastic and deterministic approaches), a time-history record that matches the target spectrum within a specified error bound. The utility of this approach is demonstrated with several collections of earthquake records from different regions of the world (Japan, Los Angeles, and San Francisco) that are then used to match various spectra widely used in seismic design applications. Issues that impact the selection of the bases vectors to construct the optimum spectra-matching record are discussed, and guidelines are provided for successful implementation of the proposed methodology.  相似文献   
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Aegyptiaca-like Domitian’s obelisk is now decorating Bernini’s fountain on Piazza Navona or the Egyptian lions flanking Michelangelo’s stairs towards the Capitol figure prominently amidst Rome’s cultural heritage. Motivations for the import, contextualization, and copying of these objects during the Imperial Roman period are as heavily debated as they are ill understood. Provenance determination plays an important role in these discussions in terms of a (supposed) dichotomy between Egyptian (real) versus egyptianising (copy) but has only been applied stylistically and never been tested analytically. A scientific characterization of the materials themselves is even lacking altogether, as is an investigation into the cultural and symbolic meaning of the materials used. This paper is a first attempt to address these important lacunae on the basis of an explorative study of a selected sample of Egyptian statues from Rome. The identification and provenance attribution of the materials used for these statues are often problematic due to their relatively fine-grained nature and dark color. Therefore, a full non-destructive analysis of Egyptian statues in dark-colored rocks is presented in this study, with the stones evaluated by macroscopic examination and handheld X-ray fluorescence (XRF) analysis. The implemented methodology has allowed a distinction between greywacke and several varieties of granitoid rocks. In order to evaluate the potential for source attribution, a comparison was made between the results of our analyses and geochemical data for several granitoid rocks from Egypt. This has suggested Aswan as most likely source. The results presented here indicate that handheld XRF analysis can be used for the assessment of compositional variability in and potentially for the provenance of granitoid rocks, provided that a fine-grained area of the material can be measured on multiple locations, and if these values can be assessed on (in)consistencies with other published reference materials.  相似文献   
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This article explores age‐ and sex‐related patterns of cortical bone loss, assessed by radiogrammetry of the second metacarpal, from a skeletal sample excavated from the Imperial Roman port city of Velia (1st and 2nd century ad ), to contribute to our understanding of health and disease during the Imperial period. Patterns of age‐ and sex‐related bone loss and health at Velia are also compared with other historical samples and to modern clinical data. It was hypothesised that patterns of age‐ and sex‐related bone loss in this well‐represented Roman sample (n = 71) would mirror those reported in modern populations. Differences in the quantity of cortical bone between three age groups (18–29, 30–49 and 50+ years) are significant in both men and women; however, the pattern of bone loss differs between the sexes. Women show a gradual decline in bone quantity beginning in middle age, whereas men only lose bone in old age. However, there are no significant sex differences at any age group in the metacarpal cortical index. These findings suggest the hypothesis should be refuted because significant sex differences, particularly in old age, are an expected hallmark of bone loss in Western populations today. The possible biocultural and gender‐related factors that may have contributed to the observed patterns of bone maintenance and loss at Velia are discussed. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
335.
Carbon sequestration in community forests presents a major challenge for the Reducing Emissions from Deforestation and Forest Degradation (REDD+) programme. This article uses a comparative analysis of the agricultural and forestry practices of indigenous peoples and settlers in the Bolivian Amazon to show how community‐level institutions regulate the trade‐offs between community livelihoods, forest species diversity, and carbon sequestration. The authors argue that REDD+ implementation in such areas runs the risk of: 1) reinforcing economic inequalities based on previous and potential land use impacts on ecosystems (baseline), depending on the socio‐cultural groups targeted; 2) increasing pressure on land used for food production, possibly reducing food security and redirecting labour towards scarce off‐farm income opportunities; 3) increasing dependence on external funding and carbon market fluctuations instead of local production strategies; and 4) further incentivising the privatization and commodification of land to avoid transaction costs associated with collective property rights. The article also advises against taking a strictly economic, market‐based approach to carbon sequestration, arguing that such an approach could endanger fragile socio‐ecological systems. REDD+ schemes should directly support existing efforts towards forest sustainability rather than simply compensating local land users for avoiding deforestation and forest degradation.  相似文献   
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This article examines the role of the Irish co-operative movement in the early twentieth century and argues that it played a crucial role in shaping a popular understanding of the “Irish Question”. This mass-membership movement impacted upon the development of the Irish state and population. By taking this rural, social movement as a lens to analyse Irish society in the early twentieth century, social and economic issues re-emerge as central components to a contemporary understanding of Ireland's increasingly contested position within the Union. As the expectation of some kind of political resolution to demands for political independence grew during the First World War, radical nationalism absorbed a social and economic discourse that originated within the co-operative movement in its critique of the British state as it operated in Ireland. Irish co-operation represented a sophisticated form of political economy that provided an influential ideological platform for Irish nationalists as they anticipated some form of political independence.  相似文献   
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Stable carbon and nitrogen isotope analysis was applied to archaeological specimens of the commensal Pacific rat (Rattus exulans) to investigate nutrient fluxes in prehistoric socio-ecosystems on Mangareva (Gambier Islands) and their implications for anthropogenic environmental change. The Pacific rat – ubiquitous in Polynesian archaeological sites – is characterised by low dietary selectivity and a limited home range, making it an ideal candidate for assessing changes in island food webs. Temporal trends in diet-derived bone collagen δ13C and δ15N values are assessed from three sites: The Onemea Site, Taravai Island (TAR-6), Nenega-iti Rockshelter, Agakauitai Island (AGA-3) and Kitchen Cave Rockshelter, Kamaka Island (KAM-1). An overall trend of decreasing δ15N values in rat bone collagen over time reflects archipelago-wide changes to island socio-ecosystems most likely resulting from seabird population declines. Differences in site function and human activity may have also influenced local rat dietary patterns. Stable isotope analysis of the Pacific rat provides a low-impact line of evidence towards the reconstruction of human-centred food webs and the flow of nutrients within island socio-ecosystems.  相似文献   
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