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51.
Four decades have passed since Harlan and Stemler (1976) proposed the eastern Sahelian zone as the most likely center of Sorghum bicolor domestication. Recently, new data on seed impressions on Butana Group pottery, from the fourth millennium BC in the southern Atbai region of the far eastern Sahelian Belt in Africa, show evidence for cultivation activities of sorghum displaying some domestication traits. Pennisetum glaucum may have been undergoing domestication shortly thereafter in the western Sahel, as finds of fully domesticated pearl millet are present in southeastern Mali by the second half of the third millennium BC, and present in eastern Sudan by the early second millennium BC. The dispersal of the latter to India took less than 1000 years according to present data. Here, we review the middle Holocene Sudanese archaeological data for the first time, to situate the origins and spread of these two native summer rainfall cereals in what is proposed to be their eastern Sahelian Sudan gateway to the Red Sea and the Indian Ocean trade.  相似文献   
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Non-urbanized areas (NUAs) play an important role in reducing the effects of climate change by providing both carbon storage and sequestration. Urban areas are responsible for the emission of 60% of global greenhouse gas, 50% of which are produced by buildings. During the past decades, increasing urban growth and sprawl processes produced several urban layouts characterized by different morphological features and a common lack of sustainable energy and environmental solutions. Investigating the relationship between urban morphology, energy demand and carbon emission/sequestration represents a relevant topic for urban planning practices implemented to face urban climate change effects. This study proposes a method for a transformability assessment aimed at investigating the transformation suitability of different urban morphology types. The case study is the metropolitan area of Catania (Italy), characterized by an impressive urban growth since the 1960s. The proposed method identification of limits and options for increasing sustainability of urban areas considering the contribution of both NUAs and built-up areas. This approach allows to identify appropriate planning tools for new layouts of urban fabrics while increasing the objectivity of the decision process. In the framework of climate change mitigation and adaptation, the outcomes of this research may lead to innovative urban planning practices.  相似文献   
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Regional design, long a backbone for spatial planning, even if under other names, has become topical again for two reasons – as a key strategy and as a key tool in spatial management. This is due to several reasons. New conditions of urbanization that result from the convergence of several factors highlight the need for spatial strategy formation and application at supra-metropolitan scales. These new conditions include globalization, climate change, booming urban population, increased mobility and interconnectivity, and new infrastructure technologies. These forces driving urbanization today and into the future play out at the urban scale, which is increasingly encompassed in the city-region. The solutions to the impacts and problems that these forces cause must be dealt with by a strategic urbanism at a scale that matches. This scale of urbanism can be denoted as regional design. To justify these claims and to understand the origins of regional design and its relevance today and into the future, the master strokes in its history are presented next. After that, we discuss current concepts and practices in regional design. In conclusion, we offer answers to the question: why a resurgence of regional design?  相似文献   
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ABSTRACT

Climate change impacts will increase in their frequency and severity in the coming decades, resulting in compromised integrity or destruction of thousands of heritage resources. Efforts are needed to identify, record, and study resources that will be affected. To set research and preservation priorities, the vulnerability of resources to climate change impacts and their importance to scientific research, preservation, and other resource values needs to be understood. We advocate a modelling approach which predicts the location, timing, and severity of climate change impacts; identifies resources at risk, their resource values, and opportunity costs; and prioritises research and preservation options based on these assessments. The need for this approach is illustrated with examples from two coastal areas subject to different impacts and hosting different types of heritage resources: the Atlantic coast of Georgia in the United States and the Wismar Bight along the Baltic Sea in northern Germany.  相似文献   
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Telepresence-enabled exploration of deep sea environments has developed over the past 30 years, providing access to archaeologists, scientists, and the general public to sites otherwise inaccessible due to depth. Pioneered through the inception of the JASON Project in the late 1980 s, telepresence missions have expanded to two dedicated ships of exploration, NOAA Ship Okeanos Explorer and exploration vessel Nautilus, and has been implemented on a series of opportunistic missions on other vessels. This paper chronicles the history of the use of telepresence for the exploration of shipwrecks in deep water as well as how this capability has allowed the public to engage with such missions. Broadening the scope of who can explore the deep sea, telepresence has also expanded what is observed and documented in the deep, which speaks to humanity’s use of the maritime world and an archaeology of discard through our material disposed of into the deep sea.  相似文献   
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This study heeds the call for a ‘truth-telling’ of injustices carried out on Aboriginal communities during the colonial acquisition of Australia as stated in the Uluru Statement from the Heart 2017. Here, we discuss the lives of eight Indigenous people buried in Normanton in north-west Queensland (QLD) who died and had their remains collected in the late 1890s as scientific specimens. The remains were later repatriated to the community before being further exposed by erosion in 2015. With the consent and participation of local traditional owners—the Gkuthaarn and Kukatj people—this assessment utilised bioarchaeological, historical and anthropological methodologies to gain a better understanding of Indigenous life and health on the Australian colonial frontier. Gkuthaarn and Kukatj people were engaged throughout the investigation, and statements throughout this piece made by them illustrate how bioarchaeology can inform on past injustices in Australia’s history, bringing them into the public consciousness and aiding the transition to reconciliation through ‘truth-telling’.  相似文献   
60.
We exploit a recent generalization of the Thrust Network Analysis (TNA) to analyse masonry structures of extremely complicated and audacious geometry such as helicoidal staircases. Actually, differently from available methods, based on ad-hoc solutions holding for each particular structure, the TNA allows for studying the equilibrium of structures of arbitrary shape by invoking the principles of limit analysis of masonry structures dictated by Heyman. Four paradigmatic monumental staircases, with increased degree of complexity, have been selected as case studies in order to show the versatility and accuracy of the proposed approach. The results entailed from the generalized TNA are also successfully compared, for the first time in the literature, with those related to the adoption of available analytical methods for the analysis of no-tension membranes.  相似文献   
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