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91.
GML作为一种空间信息的编码、存储和交换格式,已逐渐被接受并广泛使用,为实现空间信息的共享和WebGIS的进一步发展提供了一个强有力的工具;SVG作为一种网络时代的图形文件格式标准,综合了矢量图形、位图图像和纯文本的优点,对网络环境有天然的适应性,代表未来网上图形传输发展的方向,因此,基于GML&SVG的WebGIS研究与应用具有广泛的实用价值和应用前景。文中提出了利用GML进行地理信息的存储和集成,并用SVG实现地理信息的Web显示,操作的开放式WebGIS体系结构和解决方案。且在此基础上,建立了GML&SVG的WebGIS应用系统。 相似文献
92.
Suphanut Jamonnak Shamal Al-Dohuki Xinyue Ye Farah Kamw 《International journal of geographical information science》2020,34(11):2115-2135
ABSTRACT Videos embedded with spatial coordinates, especially when combined with additional expert insights, offer the potential to acquire fine-scale multi-time period contextualized data for a variety of different environments. However, while these geospatial multimedia (GSMM) data include abundant spatiotemporal, semantic and visual information, the means to fully leverage their potential using a suite of visual and interactive analysis techniques and tools has thus far been lacking. In this paper, we address this gap by first identifying the types of tasks required of GSMM data, and then presenting a solution platform. This GeoVisuals system utilizes a visual analysis approach built on semantic data points that can be integrated spatially, which in turn enables management in a unified database with combined spatio-temporal and text querying. A set of visualization functions are integrated in two investigation modes: geo-video analysis and geo-location analysis. 相似文献
93.
《Marine Policy》2015
This study examines the current state of the art in the emerging and strategically important marine biotechnology sector in Oman, which has a long coastline, rich marine heritage and strong fishing industry. In a knowledge-based economy, the ability to innovate is a key factor for increasing organisational competitiveness and this may be achieved using open innovation. This is the use by firms of external knowledge, ideas and technology to innovate. In this study, the extent of open innovation in Omani marine bioindustry companies has been studied by examining data from the top sixteen companies ranked by number of employees. The results indicate that the extent of openness in these companies is higher towards market side activities. In addition, the use of open innovation to increase collaboration between companies, Universities and government research institutes needs to be significantly strengthened. 相似文献
94.
Regional models actively forced with data from larger scale models at their open boundaries often contain motion at different time-scales (e.g. tidal and low frequency). These motions are not always individually well specified in the forcing data, and one may require a more active boundary forcing while the other exert less influence on the model interior. If a single relaxation time-scale is used to relax toward these data in the boundary equation, then this may be difficult. The method of fractional steps is used to introduce dual relaxation time-scales in an open boundary local flux adjustment scheme. This allows tidal and low frequency oscillations to be relaxed independently, resulting in a better overall solution than if a single relaxation parameter is optimized for tidal (short relaxation) or low frequency (long relaxation) boundary forcing. The dual method is compared to the single relaxation method for an idealized test case where a tidal signal is superimposed on a steady state low frequency solution, and a real application where the low frequency boundary forcing component is derived from a global circulation model for a region extending over the whole Great Barrier Reef, and a tidal signal subsequently superimposed. 相似文献
96.
97.
针对大型室内场所实时监控系统面临的地图可视化功能不足的问题,文章结合室内定位监控系统需求,提出一种基于开源WebGIS技术的实时定位监控系统室内地图可视化方案,基于Web三层体系分别设计了室内地图符号化方案、管理方案以及Web监控端显示方案;最后设计开发了一套室内实时定位监控系统HospMonitor,并在医院进行了应用实验,能够实现对医院特定人员进行实时定位、动态追踪和查询分析等功能,该方案提升了现有实时定位监控系统中的室内地图可视化性能,可推广应用于大型室内场馆实时监控管理应用中。 相似文献
98.
Anita Moldenhauer-Roth Guillaume Piton Sebastian Schwindt Mona Jafarnejad Anton JSchleiss 《国际泥沙研究》2021,36(1):136-150
Sediment detention basins are implemented on mountain rivers to trap solid material that may aggravate the flooding of downstream settlements.However,retention structures built in the past may unnecessarily retain sediment during non-hazardous flood events,resulting in high maintenance costs and sediment deficit downstream.In addition,the so-called spontaneous self-flushing of previously retained sediment during floods has occasionally been observed.Recent research suggests to design sediment detention basins for controlling sediment passage with a guiding channel across the deposition area upstream of a hybrid barrier.Such barriers consist of a check dam with a slot orifice and an upstream bar screen with a bottom clearance in order to benefit from a combined mechanical-hydraulic retention control.The present paper enhances this pioneering research with the help of new experimental data,including a wide range of sediment mixtures and large wood,as well as variable barrier heights.Improved design criteria are provided regarding the bar screen and the basin storage capacity.The functionality of the enhanced concept for sediment detention is illustrated by a case study on a physical model:the protection of the Villard-Bonnot village(France)against torrential hazards. 相似文献
99.
GIS软件的发展方向研究 总被引:1,自引:0,他引:1
GIS软件发展到现在已经到了一个比较成熟的阶段。开源GIS的提出,从本质上为GIS软件的新发展提供了方向。开源GIS以开放、分享的特点将会成为以后GIS软件研发的主流方向。文章概述了开源GIS的基本构架、数据类型和优势特点,同时从研发角度以及商业角度分析了开源GIS的意义。 相似文献
100.
I. ISTIARTO W.H. GRAF Res. Asst. Lab. de recherches hydrauliques Ecole Polytechnique Federale Lausanne Switzerland. E-mail: adhy.kurniawan@epfl.ch or istiarto@tsipil.ugm.ac.id Prof Lab. de recherches hydrauliques Ecole Polytechnique Federal 《国际泥沙研究》2001,(4)
1 INTRODUCTION'LOcal scour around a pier is a result of the interatiOn amongst the pier, the aPproach flow and theerodible bed. The Presence of a pier results in a stagnation pressure build-up in front of the pier and athree-dimensional tUrbulent flow echaracterized by the downward flow ahead of the pier and the so-called horseshoe vortex along the base of the Pier forms itself The flow modifies the erothe bed inthe vicinity of the pier when local scour takes place (Graf and AJhnakar l… 相似文献