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321.
322.
任亚文  杨宇 《地理科学进展》2022,41(9):1622-1634
产业布局的区位关联是区域产业空间结构及其空间关系研究的重要内容。论文通过构建珠三角地区半导体企业数据库,并采用核密度分析与协同区位分析方法对珠三角地区半导体产业空间格局及其区位关联特征进行研究。研究发现:① 广深莞三地是珠三角地区半导体产业空间的重要集聚区,半导体设计环节是珠三角地区进入半导体产业链的普遍选择。② 广州尽管在设计、材料和分立器件制造方面形成了专业化集群,但其仅有分立器件制造环节与设计和封测环节形成了区位协同关系;而深圳则以设计设备两大专业化集群为支撑形成了与其他所有环节的区位协同,总体上形成了较为完整的半导体全产业链。③ 广州在分立器件制造环节的专业化优势属于半导体产业链建设过程中的过渡状态,而深圳在全产业链建设方面的优势则建立在大量数字技术企业在本地的高度集聚,通过半导体设计环节与其他环节建立了共同的知识、技术和人才基础。研究旨在为珠三角进一步优化半导体产业链布局提供决策依据,以提升区域半导体产业竞争力。  相似文献   
323.
Soil heterogeneity and data sparsity combine to render estimates of infiltration rates uncertain. We develop reduced complexity models for the probabilistic forecasting of infiltration rates in heterogeneous soils during surface runoff and/or flooding events. These models yield closed-form semi-analytical expressions for the single- and multi-point infiltration-rate PDFs (probability density functions), which quantify predictive uncertainty stemming from uncertainty in soil properties. These solutions enable us to investigate the relative importance of uncertainty in various hydraulic parameters and the effects of their cross-correlation. At early times, the infiltration-rate PDFs computed with the reduced complexity models are in close agreement with their counterparts obtained from a full infiltration model based on the Richards equation. At all times, the reduced complexity models provide conservative estimates of predictive uncertainty.  相似文献   
324.
风暴潮灾害风险评估研究综述   总被引:3,自引:0,他引:3  
我国是受风暴潮影响最严重的少数国家之一,风暴潮灾害致灾机理的研究在过去几十年取得了极大的进展,而风暴潮脆弱性评估和综合风险评估还不能满足风暴潮灾害风险管理的需求.系统总结了风暴潮危险性、脆弱性、综合风险评估及其应用的研究进展,重点分析了典型重现期风暴潮估计、可能最大风暴潮计算、风暴潮物理脆弱性和社会脆弱性评估以及风暴潮风险评估及其应用的研究进展及不足,并对我国风暴潮风险评估急需解决的问题以及未来的研究重点进行了展望,指出了风暴潮灾害风险评估的模型化、系统化、定量化是未来风暴潮风险评估研究的发展趋势,风暴潮灾害的未来风险评估还需考虑全球气候变化以及海平面上升等因素的影响,而风暴潮灾害承灾体脆弱性的定量评价是风暴潮综合风险评估的重点和难点.  相似文献   
325.
Society requires increasingly that the hazard and risk associated with engineered constructions be quantified. The current paper presents geotechnical hazard assessment in the context of a risk framework. Concepts of uncertainties, reliability, safety and risk are briefly reviewed. The use of the approach is exemplified for offshore facilities, including piled foundations, jack-up structures, gravity foundations and underwater slopes. The applications demonstrate that probabilistic analyses complement the conventional deterministic safety factor and deformation-based analyses, and contribute to achieving a safe and optimum design. The probabilistic approach adds value to the results with a modest additional effort. The conclusions emphasize the usefulness of a risk assessment, the importance of engineering judgement in the assessment and the need for involving multi-disciplinary competences to achieve reliable estimates of hazard and risk. The profession can only gain by implementing probabilistic-based thinking and risk-based approaches more systematically than before.  相似文献   
326.
北京地区地裂缝成因复杂,是平原区主要地质灾害。本文总结北京地区地裂缝的勘查方法,提出了地裂缝勘查评价体系。对地裂缝现状、预测和综合评价方法进行了探讨,认为地裂缝现状危险性评价应以活动强度为主要指标,预测地裂缝潜在危险是评价的重点。建议将地裂缝成因及工程建设类型等纳入评价指标体系。  相似文献   
327.
马超  车路宽 《城市地质》2013,8(1):54-56
唐山市某住宅小区位于山前平原,第四系地层厚度35m左右,下伏基岩为奥陶系灰岩。住宅区有岩溶塌陷地质灾害。本文评价小区岩溶地质灾害危险性。  相似文献   
328.
Event Scenario Analysis for the Design of Rockslide Countermeasures   总被引:2,自引:0,他引:2  
The Torgiovannetto quarry(Assisi municipality,central Italy) is an example of a site where the natural equilibrium was altered by human activity,causing current slope instability phenomena which threaten two roadways important for the local transportation.The quarry front,having a height of about 140 m,is affected by a 182,000 m3 rockslide developed in intensely fractured limestone and is too large to be stabilized.In 2003 some tension cracks were detected in the vegetated area above the quarry upper sector.From then on,several monitoring campaigns were carried out by means of different instrumentations(topographic total station,extensometers,inclinometers,ground-based interferometric radar,laser scanner and infrared thermal camera),allowing researchers to accurately define the landslide area and volume.The latter’s major displacements are localized in the eastern sector.The deformational field appears to be related to the seasonal rainfall.The landslide hazard associated with the worst case scenario was evaluated in terms of magnitude,intensity and triggering mechanism.For the definition of the possible runout process the DAN 3D code was employed.The simulation results were used in order to design and construct a retaining embankment.Furthermore,in order to preserve both the safety of the personnelinvolved in its realization and of the roadways users,an early warning system was implemented.The early warning system is based on daily-averaged displacement velocity thresholds.The alarm level is reached if the prediction based on the methods of Saito(1969) and Fukuzono(1985) forecasts an imminent rupture.  相似文献   
329.
Many oil and HNS spill accidents occur in the waters surrounding the Korean Peninsula because Korea is one of the biggest trading partners in the world. In this study, we analyzed the oil and HNS spill accidents that occurred between 1994 and 2005 and created risk matrices to assess these accidents. The worst scenarios of future oil and HNS spill accidents were established, and the maximum spill amounts were estimated using historic accident data and a correlation from IPIECA. The maximum spill amounts are estimated to be between 77,000 and 10,000 tons of oil and HNS, respectively. One third of the spill materials should be removed using recovery equipment within three days of the spill event, according to the national measure plan. The capability of recovery equipment to remove spill materials can be estimated, and the equipment should then be prepared to mitigate the harmful effects of future oil and HNS accidents on humans and marine ecosystems.  相似文献   
330.
ABSTRACT

What can contemporary geographical research learn from Aadel Brun Tschudi? As a pioneer of development geography, Tschudi emphasised efficiency, equity and the responsibility of geographers to be active in society. While her contributions to development geography were made in the context of nation-building efforts in the mid–late 20th century, the globalising process of the early 21st century raise similar concerns for identity, emergent hierarchies of power and socio-environmental transformation. Using Tschudi’s cardinal principles of equity and efficiency, the paper identifies four action arenas and exemplifies these through interventions aimed at reducing risk and addressing unmet development challenges: (1) high efficiency, low equity (private sector led), (2) low efficiency, low equity (humanitarian sector led), (3) low efficiency, high equity (spontaneous local action), and (4) high efficiency, high equity (collaborative action). The analysis draws out the different ways in which the aspirations and policy communities that own the United Nations’ Sustainable Development Goals (SDGs) and the Sendai Framework for Disaster Risk Reduction 2015–2030 are interacting now and how far these interactions are able to deliver efficiency and equity for the poor in low- and middle-income countries, which is Tschudi’s primary concern.  相似文献   
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