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411.
Flooding is the most costly natural hazard in Europe. Climatic and socioeconomic change are expected to further increase the amount of loss in the future. To counteract this development, policymaking, and adaptation planning need reliable large-scale risk assessments and an improved understanding of potential risk drivers.In this study, recent datasets for hazard and flood protection standards are combined with high resolution exposure projections and attributes of vulnerability derived from open data sources. The independent and combined influence of exposure change and climate scenarios rcp45 and rcp85 on fluvial flood risk are evaluated for three future periods centered around 2025, 2055 and 2085. Scenarios with improved and neglected private precaution are examined for their influence on flood risk using a probabilistic, multivariable flood loss model — BN-FLEMOps — to estimate fluvial flood losses for residential buildings in Europe.The results on NUTS-3 level reveal that urban centers and their surrounding regions are the hotspots of flood risk in Europe. Flood risk is projected to increase in the British Isles and Central Europe throughout the 21st century, while risk in many regions of Scandinavia and the Mediterranean will stagnate or decline. Under the combined effects of exposure change and climate scenarios rcp45, rcp85, fluvial flood risk in Europe is estimated to increase seven-fold and ten-fold respectively until the end of the century. Our results confirm the dominance of socioeconomic change over climate change on increasing risk. Improved private precautionary measures would reduce flood risk in Europe on an average by 15%. The quantification of future flood risk in Europe by integrating climate, socioeconomic and private precaution scenarios provides an overview of risk drivers, trends, and hotspots. This large-scale comprehensive assessment at a regional level resolution is valuable for multi-scale risk-based adaptation planning.  相似文献   
412.
针对建立生态型公路需要对现有公路近况有整体评价和把握,而目前公路评价缺少统一的评价模型、指标体系选取较分散的问题,研究对公路按照主因素做分段处理,选取5个评价指标,建立了公路精细化评价体系。为了得到GIS可视化分析参数,在指标量化过程中将评价指标分成主观指标和客观指标分别量化,并计算精细化评价参数,以两个评价参数线性之和作为最终评价参数。最后运用GIS空间分析对唐山环湖路进行了探索性可视化分析,为我国的公路建设和公路养护提供建议性方案。  相似文献   
413.
实现单位统一、量值准确可靠的检测,是科技工作成功的前提,务必使用法定计量单位,在硬件、软件受控满足法制计量要求条件下,获取优质可溯源的量值 R_opt±u(R_opt )=(R ?-?R)±√(u_j^2 (R)+u_i^2 (R) ) 由此导出校准j、测量i两阶段、矢量合成简化计算测量不确定度的方法。特别有利于有多种标样的实验室,以标样做加密质控样,随机插入批样中,由管理者对n (≥11)批质控样结果统计的系统误差?R和标准测量不确定度u(R),同时完成签发检测报告,考核检验员素质和常态化提供测量不确定度三大使命,履行对客户的检测值品质的承诺。  相似文献   
414.
This paper provides an example of how communities can adapt to extreme forms of environmental change and uncertainty over the longer term. We analyse the interactions between scientists, communities and risk managers and examine the interpretation and communication of uncertain scientific information during a long-lived volcanic eruption in Tungurahua, Ecuador. This is complemented with a detailed study of the eruptions of 2006 and 2014, which exemplifies the complexity of interactions during periods of heightened volcanic activity. Our study describes how a ‘shadow network’ has developed outside of, but in interaction with, the formal risk management institutions in Ecuador, improving decision-making in response to heightened volcanic activity.The findings suggest that the interactions have facilitated important adaptations in the scientific advisory response during eruptions (near-real-time interpretation of the volcanic hazards), in hazard communication, and in the evacuation processes. Improved communication between stakeholders and the establishment of thresholds for evacuations have created an effective voluntary evacuation system unique to Tungurahua, allowing people to continue to maintain their livelihoods during heightened volcanic activity and associated periods of uncertainty. Understanding how shadow networks act to minimise the negative consequences of volcanic activity provides valuable insights for increasing societal resilience to other types of hazards.  相似文献   
415.
A method of combining 3D Kriging for geotechnical sampling schemes with an existing random field generator is presented and validated. Conditional random fields of soil heterogeneity are then linked with finite elements, within a Monte Carlo framework, to investigate optimum sampling locations and the cost-effective design of a slope. The results clearly demonstrate the potential of 3D conditional simulation in directing exploration programmes and designing cost-saving structures; that is, by reducing uncertainty and improving the confidence in a project’s success. Moreover, for the problems analysed, an optimal sampling distance of half the horizontal scale of fluctuation was identified.  相似文献   
416.
In order to assess the performance of the common temperature-index melt model at both spatial and temporal scale in Qilian Mountains, we performed the sensitivity and uncertainty analysis on the parameters of a common temperature-index method and evaluated the glacier mass balance on a small alpine glacier, which is separated into two relatively independent branches, with the daily mass balance and the meteorological data in the summer of 2011 and 2012. Sensitivity analysis was conducted by perturbation analysis and uncertainty analysis was carried out by Generalized Likelihood Uncertainty Estimation (GLUE) for different conditions. The results showed that the temperature-index method could properly capture the diurnal variability of the glacier mass balance. But strong equifinality of model parameter existsed in model calibration due to the uncertainty in the parameters. The model was very sensitive to changes in the value of Kice, followed by the Ksnow and Ts. It was also found that the GLUE approaches could estimate and derive the posterior distributions of 3 parameters properly. Moreover, there existed an acceptable range, which ensured high precision under different conditions.  相似文献   
417.
Aspects of urban transportation have significant implications for resource consumption and environmental quality. The level of travel activity, the viability of various modes of transportation and hence the level of transportation-related emissions are influenced by the structure of cities, i.e., their urban forms. While it is widely recognized that satellite remote sensing can provide spatial information on urban land cover and land use, its effective use for understanding impacts of urban form on issues such as transportation requires that this information be integrated with relevant demographic information. A comprehensive bi-national urban database, the Great Lakes Urban Survey (GLUS), comprising all cities with populations in excess of 200,000 has been created from Landsat imagery and national census and transportation survey information from Canada and the United States. A suite of analysis tools are proposed to utilize information sets such as GLUS to investigate the link between urban form and work-related travel. A new indicator, the Employment Deficit Measure (EDM), is proposed to quantify the balance between employment and worker availability at different transit horizons and hence to assess the viability of alternate modes of transportation. It is argued that the high degree of residential and commercial/industrial land uses greatly impact travel to work mode options as well as commute distance. A spatial interaction model is developed and found to accurately predict travel distance aggregated at the census tract level. We argue that this model could also be used to explore the relative levels of travel activity associated with different urban forms.  相似文献   
418.
Streamflow response of Belgian catchments to IPCC climate change scenarios   总被引:8,自引:0,他引:8  
The IRMB (Integrated Runoff Model—F. Bultot) daily step conceptual model has been applied to eight Belgian catchments with areas ranging from 100 to 1200 km2. These catchments are characterized by various infiltration rates and ground water storage capacities. The outputs of six GCMs (General Circulation Model) distributed by the IPCC (Intergovernmental Panel on Climate Change) and an earlier scenario have been used to perturb time series of hydrometeorological input data relevant to simulate the water cycle. This paper focuses on the impacts on streamflow and its surface and underground components, as well as on the occurrence of flood days and low flow days. Impacts are shown to be catchment and scenario dependent. Due to the scenario diversity, streamflow impacts are found to be either positive or negative. The trends are common to scenarios with the same patterns or to catchments with similar characteristics. For all but two scenarios, all the catchments present an increase of flood frequency. Nevertheless, for all the scenarios, catchments with prevailing surface flow are undergoing an increase in flood frequency during winter months.  相似文献   
419.
对 GIS中不定性因素的研究目前是一个热门的课题 ,许多 GIS研究人员提出了各种顾及不定性的 GIS空间数据结构 ,但是绝大多数只能停留在理论阶段 ,难以实施 ,其主要原因一是由于数据结构本身的复杂性 ,另外一个很重要的原因便是在这种数据结构中 ,对隶属度的获取很困难或很不精确 ;本文作者在介绍了顾及不定性的 GIS空间数据结构的基础上 ,引入了一种计算隶属度的方法 ,并以边界锐度这一概念扩展了传统的边界含义 ,实验结果证明所提方法是切实可行和易于操作的  相似文献   
420.
 A comparison is made between a circular and a more adequate spherical reaction-diffusion multi-media mass balance model. This comparison adds new aspects to ongoing debates about more effective assessments of potentially harmful substances including persistent organic pollutants (POPs). The circular model serves as a paradigm in investigations of persistence and spatial range of non-polar chemicals. An analytic solution of the spherical model is presented. It is utilized in order to establish circular spatial ranges as versatile approximations of their spherical counterparts for most cases. Deviations in the few exceptions are demonstrated as playing a minor role compared to sensitivities against parameter uncertainties which characterize these exceptional cases as well. The sensitivities are fundamentally linked to the multi-scale nature of the underlying system. Finally, the insensitivity of spatial ranges with respect to dimension – circle versus sphere – is further secured by extensive studies of the role of the mode of entry for which a set of rules is established. Present address: Potsdam Institute for Climate Impact Research P.O. Box 60 12 03, D-14412 Potsdam, Germany e-mail: held@pik-potsdam.de The author would like to thank B. H. Hawkins, H. A. Schweers, and M. Str?be for helpful comments.  相似文献   
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