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11.
参与式农村发展理论与实践—来自滇川黔地区的经验 总被引:3,自引:3,他引:3
参与式发展是80年代末初形成的一种发展学理论和方法,完成从学术研究到发展实践的变成,已经在大范围的政府资助的项目中应用。通过总结从事参与式农村发展引进、试验及应用的10年经验,认为参与式是发展的一种思想和一套简单和可视的方法,能够有效地协助受教育少的村民分析自己面临的问题,寻找可行和适合于他们自身条件的解决办法,提高项目受益者自己的能力。参与式的应用和推广需要一批有参与式理念和经验的发展工作者,更重要的是培养基层工作者,他们在日常与村民接触的工作应用参与式的方法。实践者除了行为、态度的转变和熟练应用参与式方法的技巧外,还需要有培训的能力、协调和协助的技巧、机构管理与项目管理的知识、以及咨询服务的技能。 相似文献
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《Geoforum》2017
Assemblage approaches are increasingly being used to understand new socio-natural formations arising in relation to the multiple crises of capitalism, climate change and environmental degradation. The valuation of nature is key to these new formations, which the creation of new ‘valued entities’, through calculative practices, that can be accounted for, costed and circulated in monetised and financialised forms in order to ostensibly ‘fix’ certain environmental outcomes in relation to contemporary global crisis. This paper uses an assemblage approach in relation to the global’ transnational project of carbon forestry offsetting and REDD+ in a particular place, Uganda, arguing that it has utility in this respect. While Uganda has been named by Lang and Byakola (2005) as a ‘funny place to store carbon’ due to its contested land politics and history of violence its weak governance context paradoxically re-enforces the imperative for intervention. The paper argues that carbon forestry assemblages are inherently ephemeral and fundamentally contested in three ways: exhibiting a speculative virtuality, faltering materiality and disputed territoriality. Such analysis has the ability to go beyond technical and managerial, or solely pollical economic critiques of carbon forestry, to point at openings for alternatives. 相似文献
13.
《Geoforum》2017
In the current environment of austerity, social justice concerns are increasingly permeating the food security agenda. However, there is a need to clarify what it means to create socially just food systems conceptually and practically. To address this gap, this paper proposes an analytical framework to embed a more complex conceptualisation of justice in food security debates that also serves as a bridging device across competing narratives. This framework is mobilised to analyse the framing process of the UK media, which plays a key role in developing narratives that provide audiences with schemas for interpreting events. Results show the emergence of eleven frames which highlight different solutions to deliver food security. The application of the justice analytical framework evidences the contingent relationship between food security and justice claims and discusses how these food security frames address differently what counts as a matter of justice (including economic, socio-cultural and political dimensions) and who counts as a subject of justice, tackling issues around delimitation of scales and sites of justice. The analysis reveals polarised positions between whether the sites subject to justice should be individuals or structures and uncovers how political and global elements of justice are largely by-passed in food security debates. These conceptualisations of justice and associated policy recommendations neglect the potential for people to participate fully in the conditions and decisions that give rise to particular distributions of goods and bads in the first place; limiting the construction of shared responsibilities to deliver global and participative food justices. 相似文献
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Development and validation of nonlinear computational models of dispersed structures under strong earthquake excitation 下载免费PDF全文
Armen Derkevorkian Sami F. Masri Yozo Fujino Dionysius M. Siringoringo 《地震工程与结构动力学》2014,43(7):1089-1105
Structural health monitoring of large multispan flexible bridges is particularly important because of their important role in civil infrastructure and transportation systems. In this study, the response of the Yokohama Bay Bridge (YBB), a three‐span cable‐stayed bridge, to the 2011 Great East Japan Earthquake is used to perform multi‐input multi‐output system identification studies. The extensive multicomponent measurements are also used to develop and validate data‐driven nonlinear mathematical models that can predict the response of YBB to various earthquake records and can accurately estimate its damping characteristics when the system is driven into the nonlinear response range. A combination of least‐square (parametric) and neural network (nonparametric) approaches is used to develop the mathematical models, along with time‐marching techniques for dynamic response calculations. It is shown that the nonlinear mathematical models perform better than the equivalent linear models, both for response prediction and damping estimation. The importance of having an accurate approach for quantifying the damping due to the variety of nonlinear features in the YBB response is shown. This study demonstrates the significance of constructing robust mathematical models that can capture the correct physics of the underlying system and that can be used for computational purposes to augment experimental studies. Given the lack of suitable data sets for full‐scale structures under extreme loads, the availability of the long‐duration measurements from the 2011 Great East Japan Earthquake and its many strong aftershocks provides an excellent opportunity to perform the analyses presented in this study. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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双线平行盾构隧道施工引起的三维土体变形研究 总被引:4,自引:0,他引:4
基于双线水平平行盾构施工中土体损失引起的土体变形二维解析解,建立土体变形三维解析解。取不同的纵向位置作为变量,建立土体损失率沿纵向的变化方程;考虑先行隧道施工对后行隧道的影响,分别计算两条盾构隧道施工引起的土体变形,叠加得到双线平行盾构施工引起的土体总变形。其方法能够计算土体深层沉降和水平位移,较精确地反映土体三维变形。算例分析结果表明:预测值与实测值较为吻合;土体沉降随着离开挖面距离的增加而不断增大,最终在x = -40 m左右时趋于稳定;随着先行隧道与后行隧道开挖距离的接近,最大土体总沉降量逐渐增大;土体沉降会随着深度z的增大而略微增加,但沉降槽宽度将略微减小;随着两条隧道轴线水平距离L的增大,最大土体沉降逐渐减小,沉降曲线形状慢慢由V型转变成W型,不再符合正态分布规律。 相似文献
16.
全球风险和脆弱性评估方法及其尺度转换的局限性 总被引:1,自引:0,他引:1
近年来,国际上采用一系列指标,从全球的、区域的视角测度风险和脆弱性的工作不断增多.从全球尺度看,风险和脆弱性评估方法主要包括:UNDP的灾害风险指数、哥伦比亚大学的热点项目,以及哥伦比亚国家大学环境研究所开发的美洲项目;从区域尺度看,以GTZ和印度尼西亚社区合作伙伴共同开发的基于社区的风险指数最为典型.通过国际主要文献的综述,介绍了几种主要评估方法的目标、框架、测算指标和基本要求,分析了这些评估方法在应用中的局限性,指出了不同方法在空间尺度降次、升级转换过程中的不足和难点. 相似文献
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我国某些急缺矿产找矿突破的可能途径和对策 总被引:2,自引:0,他引:2
本文探讨了对我国国民经济影响很大的几种急缺矿产,包括铜、金、金刚石、钾盐找矿突破的可能途径和对策。提出深化成矿环境研究,加强矿带外围、深部及周边邻国成矿区的综合研究,加强地台边缘活动带普查工作,因地制宜选择最佳类型矿床,努力提高成矿理论研究水平是加强矿产勘查与找矿突破的重要措施。 相似文献
20.
夏津县土地风沙化及其整治对策 总被引:1,自引:0,他引:1
夏津县土地风沙化问题突出,以农田土壤风蚀为主,以旱季最为严重。增加植被盖度,完善防护林体系,合理使用土地资源,是其整治的主要对策。 相似文献