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991.
Resilience is a multidimensional concept that is increasingly used to understand environmental change in hydrological systems. Yet, the current discussion about water governance and resilience remains relatively limited, with resilience typically seen as a normative outcome for governance (i.e., to be resilient against change). Using a theoretical multiplicity approach, we explore how the theories of social-ecological systems (SES), resilience and interactive (water) governance can provide new insights for water governance studies. We propose a resilience–governance framework that captures the partly overlapping but distinct characteristics from these three theories. The framework aims to develop a more nuanced way of using resilience-thinking for water governance, viewing resilience as a function of three capacities (absorptive, adaptive and transformative capacity) and noting the simultaneous existence of three interpretations for resilience (as a property, process and outcome) across different scales. The framework also considers issues of power and equity, which are often missing from resilience framings. We illustrate the framework with two case studies – the Tonle Sap Lake in Cambodia and a small sub-catchment of the Limpopo River Basin in South Africa – to provide two distinct examples of the possibilities of resilient governance. Finally, we consider what the framework suggests more broadly for ongoing discussions around resilience and water governance, including the possibilities for governance to also ‘bounce forward’ – i.e., transform – to a new, improved state. We argue that resilience-thinking may be valuable in understanding governance characteristics and guiding governance processes, in addition to seeing resilience (just) as a normative end-goal. In this way, the article supports an epistemological shift away from focusing on institutional structure, towards capturing the dynamic processes within governing systems. 相似文献
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994.
K. Geetha Manjari G. L. Sivakumar Babu 《Georisk: Assessment and Management of Risk for Engineered Systems and Geohazards》2018,12(1):60-73
As per the regulatory requirements controlling the disposal of radioactive waste, the performance of waste disposal facilities needs to be assessed quantitatively using predictive models. This estimates the potential impact of disposal on the environment and public health. Near Surface Disposal Facilities (NSDFs), constructed to contain the low level radioactive waste are considered to model the radionuclide migration from the system to the geo-sphere. The radiation dose experienced by an individual through drinking water pathway is the endpoint of assessment of the model. A three dimensional groundwater contaminant transport model with a decaying source is modelled numerically to determine the radiation dose for short-lived and long-lived radionuclides. The consideration of uncertainties constitutes an intrinsic part of modelling. The uncertain input parameters include porosity, longitudinal dispersivity, transverse dispersivity, diffusion coefficient and distribution coefficient. The uncertainty propagation and quantification is carried out using collocation based stochastic response surface method (CSRSM). To run the simulations for the huge set of input, a code is developed using built-in python interface in the numerical model. The results are processed further to obtain the sensitive parameters affecting the output concentrations. Further, the probability of radiation dose exceeding permissible value is estimated by subset simulation. 相似文献
995.
Assessment of Sentinel-1A data for rice crop classification using random forests and support vector machines 总被引:1,自引:0,他引:1
This study developed an approach to map rice-cropping systems in An Giang and Dong Thap provinces, South Vietnam using multi-temporal Sentinel-1A (S1A) data. The data were processed through four steps: (1) data pre-processing, (2) constructing smooth time series VH backscatter data, (3) rice crop classification using random forests (RF) and support vector machines (SVM) and (4) accuracy assessment. The results indicated that the smooth VH backscatter profiles reflected the temporal characteristics of rice-cropping patterns in the study region. The comparisons between the classification results and the ground reference data indicated that the overall accuracy and Kappa coefficient achieved from RF were 86.1% and 0.72, respectively, which were slightly more accurate than SVM (overall accuracy of 83.4% and Kappa coefficient of 0.67). These results were reaffirmed by the government’s rice area statistics with the relative error in area (REA) values of 0.2 and 2.2% for RF and SVM, respectively. 相似文献
996.
本文在中心主库构建成果的基础上,以实现井筒数据的一体化展示与分析为目标,提出并完成了一体化井筒综合分析系统的设计方案,从系统体系架构和系统功能的分析出发,以企业服务总线和Web Services技术为基础,以数据服务为支撑,实现了井筒数据的批量导入、编辑以及可视化浏览,通过软件机制,形成了图形模板与加载井筒数据快速生成一些图鉴的功能,以及对这些图鉴的浏览。 相似文献
997.
Local food has become a significant focus of food studies analysis in recent years with much of this work identifying the potential environmental, social and economic benefits of food localisation. However, a growing body of literature destabilises these assumed benefits with research now questioning the utility of scale in assessing food system outcomes. This paper explores this destabilisation by examining how concepts associated with the ‘local’ have been deployed by the Capital Region Farmers Market (CRFM) in the Australian Capital Territory (ACT). This leads to two key conclusions: firstly, the practical case study confirms theoretical insights highlighting the instability of the local, identifying how it is animated in multiple and sometimes contradictory ways often in response to conventional market forces; and secondly, we argue that the role of farmers' markets may not be best understood through the lens of the local but, rather, through their role in facilitating citizen engagement with the food system via the direct consumer–producer relationship at markets and the characteristics of the food purchased there (i.e. freshness and quality). In these ways, farmers' markets can disrupt conventional forms of engagement with the food system, creating a space that enhances social embeddedness and which may promote new forms of consumer understanding of food systems. 相似文献
998.
The structure of the Chilean Frontal Cordillera, located over the Central Andes flat-slab subduction segment (27°–28.5°S), is characterized by a thick-skinned deformation, affecting both the pre-rift basement and the Mesozoic and Cenozoic infill of the NNE-SSW Lautaro and Lagunillas Basins, which were developed during the Pangea-Gondwana break-up. The compressive deformation show a complex interaction between Mesozoic rift structures and thrust systems, affecting a suite of Permo-Triassic (258–245 Ma) granitic blocks. We used a combination of geological mapping, new structural data, balanced and restored cross sections and geochronological data to investigate the geometry and kinematics of the Andean thick-skinned thrust systems of the region. The thrust systems include double-vergent thick-skinned thrust faults, basement-cored anticlines and minor thin-skinned thrusts and folds. The presence of Triassic and Jurassic syn-rift successions along the hanging wall and footwall of the basement thrust faults are keys to suggest that the current structural framework of the region should be associated with the shortening of previous Mesozoic half grabens. Based on this interpretation, we propose a deformation mechanism characterized by the tectonic inversion of rift-related faults and the propagation of basement ramps that fold and cut both, the early normal faults and the basement highs. New U–Pb ages obtained from synorogenic deposits (Quebrada Seca and Doña Ana formations) indicate at least three important compressive pulses. A first pulse at ∼80 Ma (Late Cretaceous), a second pulse related to the K-T phase of Andean deformation and, finally, a third pulse that occurred during the lower Miocene. 相似文献
999.
《International Journal of Digital Earth》2013,6(2):115-142
Abstract On site observation is the most common way of monitoring cultural heritage sites and monuments in Cyprus. However, this procedure that includes data collection, periodical observations, and multivariate risk assessment analysis is difficult to accomplish with the traditional practices and methods since it is time consuming and expensive. Furthermore, many archaeological sites and monuments are located at inaccessible areas, far away from the main road network and urban areas. Satellite remote sensing and Geographical Information Systems (GIS) can successfully confront this problem by providing the scientists with integrated monitoring of the study areas and the unique advantage to store and manipulate a large amount of spatial and attribute data simultaneously. Actually the monitoring and identification of several natural and anthropogenic hazards in the vicinity of the cultural heritage sites in Cyprus, seems to be one of the main priorities of its governmental and municipal authorities. This study aims to integrate both satellite remote sensing techniques and GIS in a multidisciplinary approach, for monitoring anthropogenic and natural hazards with the use of archived and up-to-date multitemporal remotely sensed images in the study area, namely in areas nearby cultural heritage sites and monuments in Cyprus. In this study anthropogenic hazards include urbanisation and extended land use changes in the surroundings of archaeological sites and natural hazards concern seismicity and sea erosion. 相似文献
1000.
Lydell Wiebe Constantin Christopoulos Robert Tremblay Martin Leclerc 《地震工程与结构动力学》2013,42(7):1053-1068
Controlled rocking steel frames have been proposed as an efficient way to avoid the structural damage and residual deformations that are expected in conventional seismic force resisting systems. Although the base rocking response is intended to limit the force demands, higher mode effects can amplify member design forces, reducing the viability of the system. This paper suggests that seismic forces may be limited more effectively by providing multiple force‐limiting mechanisms. Two techniques are proposed: detailing one or more rocking joints above the base rocking joint and providing a self‐centring energy dissipative (SCED) brace at one or more levels. These concepts are applied to the design of an eight‐storey prototype structure and a shake table model at 30% scale. A simple numerical model that was used as a design tool is in good agreement with frequency characterization and low‐amplitude seismic tests of the shake table model, particularly when multiple force‐limiting mechanisms are active. These results suggest that the proposed mechanisms can enable better capacity design by reducing the variability of peak seismic force demands without causing excessive displacements. Similar results are expected for other systems that rely on a single location of concentrated nonlinearity to limit peak seismic loads. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献