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Determining hand laterality during human evolution is important in order to identify brain hemispheric lateralization for motor tasks and, indirectly, to gain information on the complex cognitive functions of the human brain. In this paper, we present a new method for inferring handedness from lithic evidence. The study is based on an analysis of the scatter patterns of lithic remains from stone-knapping episodes. An experimental programme was carried out by 14 knappers (eight right-handed and six left-handed), ranging from individuals that had never even struck two pebbles together to individuals who were quite familiar with prehistoric tools and had some degree of practice. The results of the experiment show that the material scatter patterns of right- and left-handed knappers at group level are different, but they do overlap at certain intervals. At the individual level, the probability of falsely ascribing left- and right-handedness has also been estimated. In addition, we have adapted this method to be applied to the archaeological record. In this case, only well-preserved knapping events with no post-depositional alterations can be used to assign left- or right-handed knappers, with the former being more reliably detected than the latter.  相似文献   
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Leapfrog development is a typical form of sprawl. This paper aims at analyzing the existence, size, and persistence of leapfrogging in a dynamic urban economic model with endogenous green amenities. We analyze whether incoming households choose to settle at the fringe of the city or to jump further away depending on their preferences and the structure of the city. We first provide an analytical treatment of the conditions and characteristics under which a first leapfrog occurs and show how the optimal choice is affected by the size of the city, income, commuting costs, as well as the size of the area where green amenities are considered. We then study how further leapfrogging and multiple urban rings may appear and be maintained in the long‐run equilibrium, and how infill processes take place through time.  相似文献   
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There is a common perception that infrastructure megaprojects are difficult to implement, as they face many obstacles (cost overruns, political barriers and time delays). This was particularly the case in the UK where many projects were difficult to develop given a complex, centralized and turbulent financial context (e.g. the jubilee Line extension, the Eurostar project). Despite this complex British system, London is developing the Crossrail mega infrastructure project which is recognized to be on time and built within a planned budget. The paper aims to analyse the reasons for the development of this project in a turbulent political and financial British system. The main argument I defend is that Crossrail benefited from the constitution of a specific and localized growth coalition. Revisiting the notion developed by Logan and Molotch, I show how the aggregation of different interests (political and economic) has been essential in the concretization of this project. Actors motivated by the will to promote the growth of London and to sustain the growth of population and jobs have been at the forefront to defend Crossrail. These elements have put Crossrail on a route of success. The paper concludes by characterizing and analysing such a success.  相似文献   
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French medical journals take the lead among the 1 385 titles of the statistical survey (15.4%). Efficient tool in communication, with an important publishing market, linked to the rise of medicine in the 19th century, prosperity of medical journals do not only mean rise of specialties. Monthly periodicals dominate quickly the publishing market which is also characterized by complex links between generalist and highly specialized medicine, public health and professional training.  相似文献   
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Abstract

This article aims at a better comprehension of urban–rural interactions as a spatial concept and its utilization for spatial and regional policies. Based on literature review and on interviews with planners and experts, the article explores how the concept of urban–rural interactions is defined, characterized and structured. The understanding of urban and rural, how they are connected provides a basis for capturing complexities and development of urban–rural interactions. The study, reviews urban–rural policies and practises in Latvia. Contemporary built-up areas and lifestyles are influenced by imprints of past urban–rural interactions. Aspects of contextuality, cross-sectorality and informality have to be taken into consideration when urban–rural interactions are applied to the policy field. The article introduces a typology to capture both the diversity and particularity of places in terms of urban–rural connectivity. An insight is given how the current Latvian local government territorial structure can contribute to building target-oriented urban–rural partnerships.  相似文献   
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The technology of the end products i.e. blades and points in Late Pleistocene stone artefact assemblages from Klasies River, South Africa, and the Nile Valley, Egypt, are compared. The comparison includes univariate and multivariate analysis of metrical attributes enhanced by graphical biplot displays. The end products in these assemblages are either dominantly points or blades and this is related to the core reduction strategy adopted. The MSA 11 from Klasies River and the Nubian Complex industry from the Nile Valley are point industries made in the Levallois tradition, while the MSA 1 from Klasies River and the Taramsan from the Nile Valley may be non-Levallois or adapted Levallois blade industries. Dating of the assemblages shows the changes between dominant core reduction strategies are sequential and time restricted in both South and North Africa. It is concluded that variability of the same kind occurs in Middle Stone Age and Middle Palaeolithic assemblages south and north of the Sahara in the early Late Pleistocene.Dans cet article, les technologies des produits recherchés, des lames et des pointes, pour certains ensembles lithiques de Klasies River, Afrique du Sud et la Vallée du Nil, Egypte, sont comparées. Cette comparaison implique des analyses univariées et multivariées de variables métriques biplot. Les produits recherchés sont bien des pointes que des lames, selon les stratégies dexploitation adoptées. Le MSA II de Klasies River et le Complexe nubien de la Vallée du Nil sont des industries à pointes issues de la tradition Levallois. Par contre, le MSA I de Klasies River et le Taramsien de la Vallée du Nil évoquent une technologie de production non-Levallois ou Levallois modifiée. Les éléments de datation disponibles indiquent que les changements dans la prépondérance des stratégies dexploitation senchaînent dans une séquence chronologique bien identifiable, aussibien dans lAfrique du Sud que lAfrique du Nord. On arrive à la conclusion quune variabilité du même caractère est attestée dans les ensembles du Middle Stone Age et du Paléolithique moyen au sud et au nord du Sahara, pendant le Pléistocène supérieur ancien.  相似文献   
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