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561.
气象部门内高性能计算资源与支持能力具有地域分布不均匀的特点,地方部门与国家级单位相比,在资源丰富程度和开发应用水平上都存在较大差距。针对气象部门国家级、地方单位的资源整合、共享和管理的需求,该文提出了一个国家气象计算网格的设计方案。设计方案采用国家级、区域、省级三级节点布局,通过跨广域范围的气象宽带网互联,基于整合的资源平台设置了资源管理、应用服务和用户接口等功能层模块。利用UNICORE等关键技术,开发实现了气象计算网格软件模块。建成了一个全国分布的6个网格节点,提供网格中间件和定制业务运行两种资源共享服务方式。业务运行以来,为资源匮乏地区的气象用户共享分发预报服务产品,为当地的减灾防灾工作做出了贡献。 相似文献
562.
Gauging extreme floods on YouTube: application of LSPIV to home movies for the post‐event determination of stream discharges 下载免费PDF全文
Raphaël Le Boursicaud Lionel Pénard Alexandre Hauet Fabien Thollet Jérôme Le Coz 《水文研究》2016,30(1):90-105
Movies taken by witnesses of extreme flood events are increasingly available on video sharing websites. They potentially provide highly valuable information on flow velocities and hydraulic processes that can help improve the post‐flood determination of discharges in streams and flooded areas. We investigated the troubles and potential of applying the now mature large‐scale particle image velocimetry (LSPIV) technique to such flood movies that are recorded under non‐ideal conditions. Processing was performed using user‐friendly, free software only, such as Fudaa‐LSPIV. Typical issues related to the image processing and to the hydrological analysis are illustrated using a selected example of a pulsed flash‐flood flow filmed in a mountainous torrent. Simple corrections for lens distortion (fisheye) and limited incoherent camera movement (shake) were successfully applied, and the related errors were reduced to a few percents. Testing the different image resolution levels offered by YouTube showed that the difference in time‐averaged longitudinal velocity was less than 5% compared with full resolution. A limited number of GRPs, typically 10, is required, but they must be adequately distributed around the area of interest. The indirect determination of the water level is the main source of uncertainty in the results, usually much more than errors because of the longitudinal slope and waviness of the free‐surface of the flow. The image‐based method yielded direct discharge estimates of the base flow between pulses, of the pulse waves, and of the time‐averaged flow over a movie sequence including a series of five pulses. A comparison with traditional indirect determination methods showed that the critical‐depth method may produce significantly biassed results for such a fast, unsteady flow, while the slope‐area method seems to be more robust but would overestimate the time‐averaged flow rate if applied to the high‐water marks of a pulsed flow. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
563.
关于“天地图”合作建设与商业运营模式的思考 总被引:2,自引:1,他引:1
简要介绍了“天地图”建设的宗旨和所提供的服务,分析了现有互联网地图服务存在的不足,遵循“分建共享,协同服务”的总体要求,探讨了“天地图”合作建设与商业运营的模式. 相似文献
564.
Abstract In the coming years the international debate on commitments for the second commitment period under the Kyoto Protocol will intensify. In this study, the Global Triptych approach is put forward as an input for international decision-making concerning the differentiation of commitments by 2020. It is a sector- and technology-oriented approach, and we calculated quantitative emission limitation objectives and global emissions starting from bottomup information on long-term reduction opportunities. Central to the calculations were long-term sustainability targets for the year 2050, formulated for (1) energy efficiency in the energy-intensive industry, (2) greenhouse gas intensity of electricity production, and (3) per capita emissions in the domestic sectors. Calculated emission limitation objectives for 13 world regions ranged from about ?30% to more than +200%. The ranking of world regions in the differentiation turned out to be independent of the levels chosen for the long-term sustainability targets. The objectives seem sufficient to maintain the long-term possibility of stabilizing atmospheric greenhouse gas concentrations at about 550 ppm CO2-eq, but will require severe emission reductions. These may be relaxed to a certain degree if stabilization at 650 ppm CO2-eq is aimed for. We conclude that the bottom-up character of the approach made it possible to examine important basic principles of the Climate Convention, including equity, the needs and circumstances of developing countries, cost-effectiveness and sustainable development. 相似文献
565.
Equitable access to sustainable development (EASD) is crucial for the future of the climate regime as it applies to adaptation, mitigation, and the means of implementation. An approach to allocating effort and deriving carbon budgets is presented here based on the United Nations Framework Convention on Climate Change (UNFCCC) principles of responsibility, capability, and sustainable development. A transparent model to operationalize EASD is applied by applying quantitative proxies for these criteria, and results for selected countries and groups are presented. A robust result is that the mitigation burden calculated by the model is significantly greater for developed than developing countries. For individual countries the results vary depending on the parameters chosen. A middle value of the mitigation burden for South Africa of 15 GtCO2e over the first half of the 21st century is reported, with the greatest effort required when a starting year of 1970 is chosen and historical land-use, land-use change and forestry (LULUCF) emissions are excluded when accounting for responsibility. In a regime applicable to all, it is clear that although all countries must do more, some must do more than others. Policy relevance Equitable access to sustainable development is crucial to the climate negotiations. Quantified allocations are presented for South Africa and other countries, based on the UNFCCC principles of responsibility, capability, and sustainable development. It is shown that the mitigation burden given these principles must be significantly greater for developed than developing countries. The results are relevant to, inter alia, the upcoming 2013–2015 review and the negotiations under the Durban Platform. 相似文献
566.
《Climate Policy》2013,13(4):465-480
Abstract This paper aims at exploring options for differentiation of future commitments in global greenhouse gas emissions control, linked to climate targets. This is done on the basis of theEUtarget of a maximum global temperature increase of 2°C compared to pre-industrial levels. The Framework to Assess International Regimes for the differentiation of commitments (FAIR) is used to explore the implications of two possible climate regimes: (1) increasing participation (i.e. a gradual increase in the number of parties involved and their level of commitment according to participation and differentiation rules) and (2) ‘contraction and convergence’ (C&C) with universal participation and a convergence of per capita emission permits. It is found that in a regime of increasing participation, stabilising the CO2 concentration at 450 ppmv by 2100 requires participation of major developing countries before 2050 in global emission control, irrespective of the participation and differentiation rules chosen. In the case of stringent climate targets, a convergence regime seems to provide more incentives for a timely participation of developing countries, and opportunities for an effective and efficient regime for controlling global emissions than increasing participation. 相似文献
567.
结合重大自然灾害应急管理的业务需求,分析了国外数据共享实践经验与案例,基于国家灾害管理实践工作经验,提出了中国建设重大自然灾害空间信息协同服务机制的构想。在进行职责任务划分的基础上,设立了包括指令中枢、数据中枢和信息中枢的立体化体制架构,并结合国家灾害管理业务工作的实际情况,制定了服务机制的业务关系流程,设定应急与常规相结合的运行模式,并对所需的保障配套机制进行了研究和分析。目前,重大自然灾害空间信息协同服务机制已经在国家灾害管理部门得到了一定范围的实践和检验,取得了较好的应用效果和社会经济效益。 相似文献
568.
基于知识本体的土地管理空间数据共享应用研究 总被引:1,自引:0,他引:1
研究目的:基于当前土地管理空间数据异构严重,难以共享的现状,探索空间数据共享的根本解决方案,实现土地管理空间数据的一体化应用。研究方法:通过研究土地管理空间数据异构的原因和空间数据共享的发展过程,提出获取土地管理空间知识,构建知识本体,建立映射模型,实现基于模型的空间数据共享的方法,并开发相应的共建数据共享平台进行了实证研究。研究结果:基于知识本体的土地管理空间数据共享方法实现了数据与应用软件的松耦合,最大限度的降低了空间对象的信息负载,有效的解决了土地管理空间数据共享的问题。研究结论:基于知识本体的空间数据共享方法是目前最有效的空间数据共享应用的解决方案,与GIS未来的发展趋势相吻合,对实现异构空间数据的共享应用有普遍的借鉴意义。 相似文献
569.
GIS点状符号共享研究 总被引:1,自引:0,他引:1
分析了GIS的3种典型符号模型不利于构建地图符号与符号间难以共享的原因,引入了PB符号模型,提出了符号数据共享与符号渲染功能共享相结合的符号共享机制,设计了3类GIS点状符号与PB符号间的映射方法,实现GIS点状符号共享,并利用实验对其进行了验证。 相似文献
570.
周天平 《测绘与空间地理信息》2011,34(2):259-261
结合作者从事多年房产测绘工作实践及<房产测量规范>的要求,阐述了房产面积测绘自接受委托开始,从对收件资料及图纸的审查、部位认定、套型边长数据的采取、房产要素的调查直到房屋面积计算分摊的整个流程中各环节的质量控制,以提高房产测绘产品的质量. 相似文献