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431.
局部地形条件对地震动放大有显著影响,解析法和数值法均可研究该问题,而解析法可以分析问题的物理本质和检验数值法的精度.将局部地形分为无盖层凹陷地形、有盖层凹陷地形(沉积谷地)、凸起地形和复合地形;分别综述了国内外关于各种局部地形对地震动影响的解析解研究成果.从以下4个方面分析和讨论当前研究成果:①研究方法;②计算介质模型;③各局部地形研究水平的不均衡;④研究存在不足之处.提出了未来发展方向:未来该领域应加强研究局部地形对Rayleigh波地震动响应规律,开展局部地形对多种波耦合入射下的地震动响应规律的研究,运用非线性波动理论研究局部地形对地震动的影响和开展三维非线性地震动数值模拟研究. 相似文献
432.
《Geoforum》2017
The Generation Challenge Programme (GCP) was an international agrarian knowledge-production programme created in 2003 by the CGIAR. GCP aims at developing drought tolerant varieties by reconciling upstream biotechnology based advanced research with the downstream development at the farmer's field. The objective of this paper is to apply the theory of Commons Based Peer Production (CBPP) to analyse the knowledge production process of GCP, especially the case of drought tolerant rice research network in Indian context (GCP-RRN). CBPP represents the theorisation of a mode of production that can be distinguished from market (private) and state (public) knowledge-production systems that was developed by observing the phenomena of Free and Open Source Software (FOSS). The organisational attributes of the CBPP mode applied in computer software production include the modulation of work, small-size granularity of components, and mechanisms that integrate these modules into an end product. Socio-economically, this form of production is based on cooperation, collaboration and collective action rather than property, contract and managerial hierarchies. This paper argues that GCP-RRN knowledge production is basically a hybridised one in which there are certain inclinations towards CBPP within certain larger context, and there are other attributes too that do not fall within CBPP theorisation. Further, this paper elaborates on the implications of this hybridised model for agrarian knowledge production discourse and institutions. 相似文献
433.
海洋调查船是专门进行海洋调查研究的工具,研究内容囊括了海洋气象、水声、物理、化学、生物、地质和水文等诸多学科,是我国海洋强国战略以及"一带一路"顺利实施的重要保障。海洋调查船按照使用的目的分为综合调查船、渔业调查船和极地调查船等。文章在各类调查船中分别选取了国内外具有代表性的船舶进行对比分析,总结了国内各类型调查船的优势和不足,对我国各类调查船的发展方向具有较好的借鉴意义。同时,文章根据对国内外调查船调查能力的对比,提出了我国调查船发展的建议:(1)完善调查船类型;(2)提高各类型船舶调查能力;(3)增加相应类型船舶数量,达到我国海洋调查需求;(4)推动海洋调查仪器设备的国产化进程;(5)加强国家海洋调查船队运行管理职能。 相似文献
434.
《Marine Policy》2017
Over the years, the breadth and depth of EU marine policy has increased with revisions of the Common Fisheries Policy (CFP) and new legislation like the Marine Strategy Framework Directive (MSFD), Integrated Maritime Policy (IMP) and the Framework for Marine Spatial Planning Directive in Europe (FMSP). Not only do these different policies have different remits and hence scope, they also present a multitude of modes of implementation. Although the CFP and MSFD have many common goals when it comes to conservation and sustainable use of living marine resources, they differ substantially in governance set up and implementation modalities, including the underlying scientific advisory processes and structures. Regional cooperation and coordination is foreseen, but there is no governance model in place to coordinate requests for scientific advice, nor institutions coordinating the activities of advice providers, either across policies or across regions. This results in an increase in uncoordinated requests for scientific advice yet the pool of experts fuelling the advisory system is limited. As a result the European marine scientific advisory system is increasingly under pressure. In this paper the consequences of this problem are analysed and a redesign of the institutional governance setting to accommodate these challenges and make the science and advice system ready for the future is explored. 相似文献
435.
按照中国大陆及邻近地区活动地块和地震区带的研究成果,选择昆仑山地震亚区为研究单元,提取研究单元1970年以来半年极大值地震.该极值地震资料具有地质单元一致的特征,也代表研究单元地震趋势水平的变化.极值地震具正态分布特征,使用7阶高斯函数模型,对资料进行最佳逼近拟合,模型中参数用最小二乘法求取,递推未来1~2年时间进行地震趋势探讨.引用定量方法探讨有关研究单元的地震趋势值得深入研究. 相似文献
436.
This paper analyses the experiences acquired through several research projects on the history of water and sanitation services by two multidisciplinary teams. Challenges have been faced in identifying feasible objectives, realistic resources, time allocations and unexpected external factors. Water history can preserve cultural heritage, promote reputation management, record vanishing knowledge, and discover new facts. 相似文献
437.
多环芳烃来源与分布及迁移规律研究概述 总被引:14,自引:0,他引:14
概述了多环芳烃的来源,就近年来多环芳烃(PAHs)在大气、土壤、植被和水体沉积物中分布与迁移规律的研究成果进行了综述,并展望了未来PAHs研究方向。 相似文献
438.
This special issue of Continental Shelf Research contains 20 papers giving research results produced as part of Australia's Torres Strait Co-operative Research Centre (CRC) Program, which was funded over a three-year period during 2003–2006. Marine biophysical, fisheries, socioeconomic-cultural and extension research in the Torres Strait region of northeastern Australia was carried out to meet three aims: 1) support the sustainable development of marine resources and minimize impacts of resource use in Torres Strait; 2) enhance the conservation of the marine environment and the social, cultural and economic well being of all stakeholders, particularly the Torres Strait peoples; and 3) contribute to effective policy formulation and management decision making. Subjects covered, including commercial and traditional fisheries management, impacts of anthropogenic sediment inputs on seagrass meadows and communication of science results to local communities, have broad applications to other similar environments. 相似文献
439.
440.
表层岩溶带及其水循环的研究进展与发展方向 总被引:19,自引:7,他引:12
表层岩溶带是现代岩溶学一个很重要的概念,表层岩溶水对于解决西南岩溶山区居民的干旱缺水问题具有重要意义。近年来,不但揭示了表层岩溶带的特征、形成的动力条件机理及其含水层特征、开展了表层岩溶的自动化监测、研究了表层岩溶水与生态环境的相关性,还对西南表层岩溶水资源进行了初步评价。今后一段时期内表层岩溶水的主要研究方向是开展表层岩溶水与管道水的耦合关系研究、生态环境调蓄表层岩溶水的功能研究及表层岩溶水资源评价。 相似文献