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431.
讨论了应用开发中的串行通信和网络通信程序实现问题,开发了一个GPS网络系统,实现了应用MSComm控件实时接收GPS卫星数据,并通过Winsock实时地向客户端发送。  相似文献   
432.
ABSTRACT

Based on research into multiple types of climate change mitigation and adaptation (CCMA) projects and policies in Cambodia, this paper documents intersecting social and environmental conflicts that bear striking resemblance to well-documented issues in the history of development projects. Using data from three case studies, we highlight the ways that industrial development and CCMA initiatives are intertwined in both policy and project creation, and how this confluence is creating potentials for maladaptive outcomes. Each case study involves partnerships between international institutions and the national government, each deploys CCMA as either a primary or supporting legitimation, and each failed to adhere to institutional and/or internationally recognized standards of justice. In Cambodia, mismanaged projects are typically blamed on the kleptocratic and patrimonial governance system. We show how such blame obscures the collusion of international partners, who also sidestep their own safeguards, and ignores the potential for maladaptation at the project level and the adverse social and environmental impacts of the policies themselves.

Key policy insights
  • Initiatives to mitigate or adapt to climate change look very much like the development projects that caused climate change: Extreme caution must be exercised to ensure policies and projects do not exacerbate the conditions driving climate change.

  • Safeguards ‘on paper’ are insufficient to avoid negative impacts and strict accountability mechanisms must be put in place.

  • Academic researchers can be part of that accountability mechanism through case study reports, policy briefs, technical facilitation to help ensure community needs are met and safeguards are executed as written.

  • Impacts beyond the project scale must be assessed to avoid negative consequences for social and ecological systems at the landscape level.

  相似文献   
433.
随着全球产能结构的转变,"清洁、安全、高效"能源的使用将是未来发展的主流,核电俨然成为优化能源结构的重要发展领域。了解、掌握境外铀矿资源勘查开发和核能发展动态,实施"走出去"开发战略是我国核电发展的重要保障。文章以权威机构发布的最新数据和UDEPO (World Distribution of Uranium Deposits,世界铀矿床分布)的数据等为基础,综合分析美洲铀矿资源、生产和需求的最新情况及主要铀资源国家的核能发展动态。结果认为,美洲铀资源丰富,在全球铀资源供给中占有重要地位,面对美洲铀资源现状及未来愈加激烈的竞争局面,掌握美洲国家核能及铀资源发展动态,对我国实施铀资源保障战略至关重要。  相似文献   
434.
Amino acid racemization (AAR) is a geochronological method that uses the ratio of D- to L-configurations in optically active amino acids from carbonate fossils to determine the time elapsed since the death of an organism. Although AAR techniques have been widely applied to foraminiferal tests, there have been limited dedicated assessments of the potential of isolating a bleach-resistant, intra-crystalline fraction of proteins to improve the reliability of AAR in this biomineral system. In this study, we evaluate the effect of two oxidative pre-treatments (hydrogen peroxide and bleach) on amino acid concentrations and D/L values in sub-modern benthic foraminifers (Ammonia spp. and Haynesina germanica) and well-preserved mid Holocene and mid Pleistocene planktic foraminifers (Pulleniatina obliquiloculata, Globorotalia truncatulinoides, and Globorotalia tumida). The oxidative pre-treatments successfully reduced the amino acid content of the foraminiferal tests to a residual fraction, and with the exception of Ammonia spp., neither pre-treatment substantially affected the relative proportion of individual amino acids. The bleaching pre-treatment does not consistently alter D/L values when compared to peroxide pre-treatment, but it does tend to reduce the subsample variability in D/L values, albeit only to a small degree in an inconsistent fashion. Therefore, we recommend that a relatively weak oxidative pre-treatment with 3% hydrogen peroxide is sufficient for foraminifera-based AAR applications.  相似文献   
435.
LiDAR点云的分类提取是点云数据处理中的首要步骤。为了提高复杂场景中点云数据分类提取方法的适用性,文中根据三维数学形态学思想,提出一种基于地物空间形状特征的点云提取方法。方法首先建立网格索引,划分网格空间,进行点云数据组织,然后根据地物在网格空间中的形状特征设计出四种参数可控的空间网格算子,最后结合点云反射强度信息自动提取特定地物点云。通过对复杂场景中的铁路地物要素LiDAR点云中建筑、电力杆线、铁路轨道的提取和郊区机载LiDAR点云中的地面与建筑屋顶的提取,验证提取算法的适用性,为点云分类提取功能模块的程序设计提供便捷方法。  相似文献   
436.
美国官方研究机构开展系统化的大数据研究已近10年,为研究美国地学大数据发展现状,基于美国地质调查局 (USGS)官网发布的由其主导的LCMAP计划的研究现状及相关软硬件设施情况等具体信息,深入了解美国科研方面的运作模式,总结可在非地学领域通用的科研项目运营技巧。同时,对比中美地学大数据应用领域的现状,提出我国在地学大数据建设方面的问题、改善思路与发展方向。  相似文献   
437.
国际大洋科学钻探可以追溯到20世纪60年代的“莫霍钻”计划。在50余年的历史中,经历了深海钻探计划、大洋钻探计划、综合大洋钻探计划和国际大洋发现计划四个阶段,执行了300多个航次的洋底钻探任务。所获得的海量、珍贵的洋底数据,如今保存在多个数据库中。这些数据包括了测井信息、岩芯基概况信息、物理属性信息、化学属性信息、岩石特征、古生物化石内容等观测和实验分析结果,数据量巨大。这些数据还通常附于相关的大洋钻探出版物中发表,部分被相关专业数据库收录。总体来看,大洋钻探目前的数字化工作存在多个数据库间数据类型不匹配和数据检索方式单调等问题,不利于后续对于数据的再挖掘和利用。未来需要重视综合性大数据平台的建设,将不同来源、不同类型的多源异构数据有效融合,互联互通,并充分利用已有的大数据技术手段支撑相关的科学研究。  相似文献   
438.
Hydraulic thresholds for erosion of fourteen upland mineral and organic soils were determined in a hydraulic flume. These soils are from areas to be afforested in the United Kingdom. Some of the group are erosion resistant but others are susceptible to erosion once denuded of vegetation; for example, by preafforestation ploughing. These threshold data were required to calibrate a hydraulic model for effective design of preafforestation drainage networks on a variety of soils. However, simple field measures of soil properties indicative of erosion potential would be of value to the forestry industry for management purposes. Consequently, hydraulic threshold data were related by linear regression methods to basic soil properties, including organic content, grain size, bulk density, compression strength and penetration resistance. The investigation concluded that four peat soils are not eroded by clear water velocities up to 5·7 m s−1, although a mineral bedload might induce erosion at lesser current speeds. Penetration resistance is a good field indicator of the degree of humification of the peat soils. Although selected physical parameters contribute resistance to water erosion, an increased organic content is pre-eminent in reducing erosion susceptibility in both organic and mineral soils. Although compressive strength was not indicative of soil erodibility, field measurements of penetration resistance on a variety of soils could be related to hydraulic thresholds of erosion; albeit through the construction of discriminant functions interpolated by eye. Consequently, organic content (laboratory) or penetration resistance (field) might form the basis of classifying upland soils in terms of erodibility. Mineral soils differ widely in terms of their erodibility, so that subject to further consideration, the use of ploughing for forestry cultivation might be appropriate in wider circumstances than presently recommended by the Forests and Water Guidelines. Ploughing should be acceptable on deep peat providing the underlying mineral soil is not exposed in the bottom of the furrow, and furrows are not led from mineral soils on to deep peat. © 1997 John Wiley & Sons, Ltd.  相似文献   
439.
城市地震灾害预测及其信息管理通用程序研究   总被引:9,自引:6,他引:3  
继承和总结了城市地震灾害预测及其信息管理系统多年以来研究和应用的成果,参照国家规范的要求,针对目前缺乏通用程序的现象,开发了城市地震灾害预测及其信息管理通用程序,并对通用程序的结构和功能、系统数据库建设、各模块的接口设计和集成等做了较详细地介绍。  相似文献   
440.
提供两个高效而实用的FORTRAN程序(例行子程序形式),用于对称三对角矩阵的两个计算问题(其一是线性代数方程组的求解,其二是广义特征值问题的计算)。在工程应用中,它们可用于多层建筑的振动特性分析、反应谱法地震变形计算、Pushover静力推覆分析和时程法地震反应分析等问题中。  相似文献   
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