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Commercial aerospace is a key sector in the Welsh economy, engaged in complex overlapping activities from aircraft manufacture (AM), through maintenance, repair and overhaul (MRO), to research, development and training (RDT). Defining and operationalizing a framework for analysis using both qualitative and quantitative data, this paper examines the actual and potential roles of the relationships in Wales between commercial aerospace firms, industry, government and institutional stakeholders, at both local and non-local levels. Concentrations of manufacturing in North Wales, and MRO in South Wales along with RDT operate as distinct constituent parts of aerospace clusters in neighbouring regions of England and beyond. The results, however, highlight links between the location of AM, MRO and RDT in Wales, emphasizing their (partially) geographically symbiotic relationships. Moreover, there are key inter-linkages that need consideration if the long-term health of Welsh aerospace is to be secured. Simultaneously, all three sub-sectors in Wales exhibit weaknesses which could render them vulnerable to greater external competition, particularly from developing countries. This emphasizes a need to alter the current governance arrangements and utilize different clustering characteristics that currently exist, with government, as a major sponsor of the industry, having a strong (but changing) role to play in encouraging these more balanced industry structures and decision-making processes.  相似文献   
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Hampe, O., Witzmann, F. & Asbach, P., 2014. A benign bone-forming tumour (osteoma) on the skull of a fossil balaenopterid whale from the Pliocene of Chile. Alcheringa 38, xxx–xxx. ISSN 0311–5518.

A pathology of the fossil baleen whale ‘Megapterahubachi from the early Pliocene of Chile is described. It is a bony outgrowth on the left side of the supraoccipital, which is interpreted as a benign bone-forming tumour (osteoma). This diagnosis is based on X-ray imaging and CT scans of the abnormal bone, revealing a homogeneously dense internal structure with no evidence for lytic areas. The osteoma described here in ‘Megaptera’ hubachi is the first unequivocal evidence of a bone tumour in a cetacean, fossil or extant.

Oliver Hampe [] and Florian Witzmann [], Museum für Naturkunde, Leibniz-Institut für Evolutions- und Biodiversitätsforschung, Invalidenstraße 43, D-10115 Berlin, Germany; Patrick Asbach [], Institut für Radiologie, Charité—Universitätsmedizin Berlin, Charitéplatz 1, D-10117 Berlin, Germany. Received 28.8.2013, revised 7.11.2013, accepted 12.11.2013.  相似文献   
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The restoration of paintings on elements in cultural heritage buildings (fundamentally, churches) involves two structural problems: capturing the geometry of the construction element and its development. In many cases, the geometries are regular (e.g., cylinders, spheres, elliptical domes). However, there are cases in which the elements cannot be adapted to any known geometry, much less one that can be mathematically developed. The development of surfaces becomes essential for the restoration of paintings over “flat elements” (over which work is performed on the ground) that are subsequently transferred to the real surface (ceilings). The mathematical transformations that allow regular geometries to be developed are widely known (cartographic projections). However, when the geometry is irregular, there is no development. This study presents a new methodology based on differential rectification and its application for the development of oculi in the Los Santos Juanes Church (Valencia), whose geometry is completely irregular both in shape and as a result of construction defects (and damage caused by fire). The present study focuses on the restoration of paintings damaged by fire.  相似文献   
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Existing research suggests that external sources of finance, such as foreign aid and natural resource rents, allow states to generate revenue independently of their societies, disincentivizing them from forming close links with their citizens and severely problematizing the notion of a social contract. In Lagos, Nigeria's commercial capital, a series of personal income tax reforms have seen an increase in taxpayer compliance. Considering Lagosians’ perceptions of their relation with the state government, this study examines whether the state had to ‘earn’ its revenue by developing a closer relationship with its citizens, and whether citizens responded through a greater willingness to pay tax. It explores how citizens understand this relationship, what role they perceive themselves to fulfil, and what their expectations are for the future of state–society relations. The study shows how, through efforts to visibly link tax to service delivery, a social contract is emerging between Lagos State and its citizens — but that this relationship differs among groups, in that it is shaped by pre‐existing concepts of public organization and modes of political engagement.  相似文献   
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The city of Herculaneum (Naples, southern Italy), buried by the volcanic eruption of Mount Somma-Vesuvius in 79 ad, is a key site for understanding the timber economy during the Roman period. In this paper, the results of charcoal analysis of different building element types are presented. Beams, joists, poles, planks and door and window frames were investigated allowing us a view of which timber the Romans preferred for building in this area. We also fit the taxonomic results into the reconstruction of the ancient Campanian landscape, and finally, we discuss the knowledge that the Romans had about the technological properties of the wood that they used for building and the possible selection criteria that they followed in choosing them. Coniferous timber is the preferred material for building purposes. Abies alba is especially used, this fact confirming its stronger presence in southern Italian woods during the past and suggesting that its decline is mainly due to human overexploitation. The large presence of Cupressus sempervirens, selectively used for the production of poles, confirms that this tree was cultivated in plantations for timber production in the Vesuvius area. Furthermore, it might indicate that cypress could have been present as a natural tree in the local vegetation, suggesting a forest type that nowadays almost completely disappeared from this area and from the entire Italy. The findings of Juglans regia, Pinus pinea and Olea europaea, typical elements of the Mediterranean cultural landscape, show that their use was not limited to fruit production and that Romans also appreciated their timber. Beside these local resources, the presence of Picea abies and Picea/Larix indicates the importation of timber from northerly regions, probably the northern Apennines and the Alps.  相似文献   
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In this paper, we argue that beyond understanding nations as imagined communities, the metaphor of an ‘imagined family’ or ‘filial community’ is a more useful concept towards understanding links between gender and nationhood as family relations in four ways: (1) providing a clear, hierarchical structure; (2) prescribing social roles and responsibilities; (3) being linked to positive affective connotations; and (4) reifying social phenomena as biologically determined. In order to empirically substantiate our claim, we will explore the prevalence and use of family metaphors in a key symbol of nationhood discourses. Through a qualitative analysis of national anthems as ‘mnemonics of national identity’, we demonstrate the widespread presence of family metaphors, discussing how they reproduce ideas of family and gender. Finally, we discuss how the ‘imagined family’ as present in anthems and other forms of national representation could inform future studies of nationalism and national politics.  相似文献   
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