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31.
In the second presidential summit of the Americas, which took place in April 1998 in Santiago de Chile, 34 heads of states of the Americas announced that they were ready to start negotiating a Free Trade Area of the Americas (FTAA), to be concluded by 2005. This article briefly discusses the current trend in favour of regional preferential trade agreements, describes how the proposal for an FTAA came about, explores more than three years of negotiations that made it possible and assesses the probability of its success.  相似文献   
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A new approach is developed for vulnerability analysis of monuments based on a matrix model and the relationships with static and structural factors, climatic conditions, air quality, urban planning and social agents for preventive conservation of cultural heritage in urban centers.

The objective is to provide tools for decision-makers in the current recession to allow them to prioritize strategies for cultural heritage preservation in a town, where territorial policies are applied and regions where restoration budget is distributed. This new tool allows to classify monuments in order to prioritize restoration and is useful in deeper analysis associated to risks assessment.

The degradation of building materials and structures is mainly due to deterioration caused by structural instability, weathering, pollution, and anthropogenic damage. The vulnerability approach of each monument (vulnerability indexes) was calculated, based on a Leopold matrix that depends on intrinsic variables and the life of the monuments. For the very first time, the influence of different deterioration agents has been balanced with a Delphi forecast based on architects’ opinions.

The result is a new pre-Artificial Intelligence tool that enables users to reproduce human reasoning to study relations between vulnerability factors, risk factors, and the historical parameters of the monuments.  相似文献   

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Spatial clusters contain biases and artifacts, whether they are defined via statistical algorithms or via expert judgment. Graph-based partitioning of spatial data and associated heuristics gained popularity due to their scalability but can define suboptimal regions due to algorithmic biases such as chaining. Despite the broad literature on deterministic regionalization methods, approaches that quantify regionalization probability are sparse. In this article, we propose a local method to quantify regionalization probabilities for regions defined via graph-based cuts and expert-defined regions. We conceptualize spatial regions as consisting of two types of spatial elements: core and swing. We define three distinct types of regionalization biases that occur in graph-based methods and showcase the use of the proposed method to capture these types of biases. Additionally, we propose an efficient solution to the probabilistic graph-based regionalization problem via performing optimal tree cuts along random spanning trees within an evidence accumulation framework. We perform statistical tests on synthetic data to assess resulting probability maps for varying distinctness of underlying regions and regionalization parameters. Lastly, we showcase the application of our method to define probabilistic ecoregions using climatic and remotely sensed vegetation indicators and apply our method to assign probabilities to the expert-defined Bailey's ecoregions.  相似文献   
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In this paper, the characterization of Roman amphorae from the Porto dos Cacos (PC) and Quinta do Rouxinol (QR) workshops, in the Tagus estuary, dating to a period between the 1st and 5th century AD was carried out on the basis of instrumental neutron activation analysis data on 260 amphorae fragments, together with mineralogical compositional studies obtained by X-ray diffraction.  相似文献   
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In the last 15 years, the regional scale was used to implement innovation strategies in European Union. Departing from the discussion of the relevance of innovation policy at the regional level, the article benefits from the knowledge production function framework to estimate patterns considering 175 European regions. It is intended to understand whether regional innovation strategies developed and applied between 1994 and 2001 were successful at an aggregated level in contributing for knowledge creation measured in terms of patents and high technology patents. The results underline the relevance of private R&D expenditure and medium and high technology employment to increase patent numbers. The models suggest also that administrative regionalization may be important to regional innovation and that the creation and implementation of a regional strategy have a positive contribution for high tech innovation.  相似文献   
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Mineralised fruits and seeds are frequently found in archaeological sediments but their chemical nature has not been often examined. The nature and the origin of these archaeobotanical remains have to be investigated to understand their taphonomic history. Fruits or seeds can be mineralised not only by replacement mineralisation but also by biomineralisation during the plant life. The mineral components of three fossil fruits sampled on the Pleistocene site of Dmanisi were analysed and compared with their modern analogues. Analyses were carried out by means of an environmental scanning electron microscope, equipped with an energy dispersive X-ray device and by means of a Fourier transform infrared spectrometer. Biogenic carbonates and/or biogenic silica were identified in the fossil and modern fruits of some taxa. Comparison between fossil and modern specimens has shown that molecular reorganisation occurred in carbonate and in biogenic silica during fossilisation, through diagenetic processes. The resulting stable mineral structures confer an exceptional preservation to fruits in sediments. Taking into account these taphonomic specificities (transformation and differential preservation), the chronological and palaeoenvironmental aspects of the mineralised fruits are discussed.  相似文献   
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