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961.
Capacity building in the marine sector is a priority for Pacific Island nations, which face major challenges in the sustainable management of their marine resources under UNCLOS III and the various Conventions and Agreements stemming from UNCED. The University of the South Pacific (USP), with its 12 Pacific Island members (Cook Islands, Fiji, Kiribati, Marshall Islands, Nauru, Niue, Samoa, Solomon Islands, Tokelau, Tonga, Tuvalu, Vanuatu) has taken up this challenge through the establishment of its Marine Studies Programme (MSP) in 1993. The MSP is one of the four focal areas identified in USP's 1998 Strategic Plan. The breadth of MSP's activities is substantial, ranging from awareness raising at the village level to sophisticated post-graduate research in marine science. The substantial regional and international cooperation, research and training involved in these endeavours require USP to respond to education, training and research needs at many levels. As USP services more than 23 million square kilometres of ocean space and less than 1.7 million people, only a small percentage of this population have access to face-to-face teaching. USP's success to date is a measure of staff dedication, innovation and the confidence of the university, its members, and its donor partners. Capacity building in the marine sector will remain a high priority for many years to come, and MSP must continue to play a leading role. 相似文献
962.
In West Africa, accurate classification of land cover and land change remains a big challenge due to the patchy and heterogeneous nature of the landscape. Limited data availability, human resources and technical capacities, further exacerbate the challenge. The result is a region that is among the more understudied areas in the world, which in turn has resulted in a lack of appropriate information required for sustainable natural resources management. The objective of this paper is to explore open source software and easy-to-implement approaches to mapping and estimation of land change that are transferrable to local institutions to increase capacity in the region, and to provide updated information on the regional land surface dynamics. To achieve these objectives, stable land cover and land change between 2001 and 2013 in the Kara River Basin in Togo and Benin were mapped by direct multitemporal classification of Landsat data by parameterization and evaluation of two machine-learning algorithms. Areas of land cover and change were estimated by application of an unbiased estimator to sample data following international guidelines. A prerequisite for all tools and methods was implementation in an open source environment, and adherence to international guidelines for reporting land surface activities. Findings include a recommendation of the Random Forests algorithm as implemented in Orfeo Toolbox, and a stratified estimation protocol − all executed in the QGIS graphical use interface. It was found that despite an estimated reforestation of 10,0727 ± 3480 ha (95% confidence interval), the combined rate of forest and savannah loss amounted to 56,271 ± 9405 ha (representing a 16% loss of the forestlands present in 2001), resulting in a rather sharp net loss of forestlands in the study area. These dynamics had not been estimated prior to this study, and the results will provide useful information for decision making pertaining to natural resources management, land management planning, and the implementation of the United Nations Collaborative Programme on Reducing Emissions from Deforestation and Forest Degradation in Developing Countries (UN-REDD). 相似文献
963.
964.
房丽秀 《测绘与空间地理信息》2017,(4)
通过GF-2号卫星影像在辽宁省1∶10 000比例尺地形图(重要要素)更新与建库的试生产,系统地阐述了项目的内容、方法、生产工艺和质量控制,验证了该方案的可行性,对保证项目的顺利进行具有重要意义。 相似文献
965.
通过对某学校图书馆变形监测,阐述了变形监测的方法和意义。主要包括变形监测网的布设、测量方法的选取、监测数据的处理,以及建筑物的沉降分析。然后在EXCEL软件上绘制建筑物的沉降趋势图,并且预测分析平均观测量和每个点位。 相似文献
966.
随着智慧城市建设的不断升级,城市管理向精细化和智能化方向快速发展.分层分户模型可以承载更复杂、更立体、更详细、更精确的信息,以供全面综合管理、大数据分析和应急指挥使用.本文以"数字郑州三维地理信息及应用服务系统"项目建设实际情况为背景,探索和实现了在SuperMap GIS平台环境下,基于楼盘表提供的层户信息与户型图提供的分户信息,通过数字线划图进行建筑底面定位,利用地名地址将楼盘表和户型图与数字线划图进行关联挂接,并根据LiDAR点云数据的高度信息,快速自动化地建设郑州市800 km2内所有建筑物的分层分户模型的技术方法.进一步探索了通过模型成果与房管信息和公安户籍信息挂接,建立"以图管房、以房管人"的新管理模式,有效提升了政府管理和决策水平.本文提出的方法技术路线先进,实操性强,具有重要的应用推广价值. 相似文献
967.
针对目前机载LiDAR点云数据存在的数据组织效率低下以及不利于查询等问题,本文提出了一种基于体元的建筑物提取算法。首先,构建体元模型实现机载LiDAR数据的真三维描述;然后,计算局部邻域曲面拟合残差,将残差最小的体元视作种子体元;最后,根据局部邻域法向量夹角准则来实现种子体元的区域增长,从而获得建筑物点。本文选取ISPRS公开的点云滤波测试数据中的8种复杂场景进行实验,实验结果表明:本文算法不仅原理简单、容易实现,而且具有较好的鲁棒性,不会受地形以及建筑物类型和尺寸的限制,Kappa系数达到80%以上,实现了复杂场景下建筑物的提取。 相似文献
968.
分析了传统城市三维建模的现状及存在的问题,指出了BIM技术应用于城市规划的重要性,同时探讨了基于BIM技术的城市三维模型系统的设计模式。将BIM技术与传统三维建模技术、地理数据库等相结合,建立建筑BIM模型,促进城市三维建模技术的创新发展,同时建筑BIM模型可嵌入城市规划项目BIM模型,贯穿于项目全生命周期,为城市规划者和管理者提供信息化的高效、便利的手段。 相似文献
969.
The Andalusian Positioning Network (RAP) is a regional GNSS permanent network in Southern Spain that offers two public services for precise positioning: real-time (RAP-Internet Protocol [IP]) and post processing (RAP-File Transfer Protocol [FTP]). Most of the registered users are linked to the construction sector, so the collapse of the housing bubble and the Spanish economic crisis influenced the use of RAP services from 2008. The behaviour of these services has differed somewhat, although analysis for the years 2008–2013 reveals a general decline. Since 2009, the RAP-FTP service demand fell by 50%, but the RAP-IP service was stable until October 2011, when it began a steep decline in December 2012. Analysing the temporal demand and the geospatial connections of RAP-IP with economic impact indicators, we found a high linear correlation between this service and jobs in the construction sector (.98) and permit building (.96). The real-time and associated geoinformation are its main advantages. 相似文献
970.
针对建筑群自动综合结果质量评价问题,该文提出一种建筑群多尺度表达中空间相似度计算模型。从地图综合质量评价的角度,立足地图综合的3个约束,即图形约束、拓扑约束、结构约束,分别计算了图形相似度、拓扑相似度、结构相似度,并对以上各相似度作了适当的权重分配,计算建筑群目标的整体相似度。最后,通过实验验证了本文相似度计算方法的正确性、可行性。 相似文献