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81.
An improvement on the simulation of outgoing waves on a time dependent numerical model for water wave propagation in the nearshore region is presented. The governing equations consist of a system of first order partial differential equations (PDEs), the equation of continuity and the equation of motion. A comparative study of first order radiation boundary conditions (BCs) and first order radiation BCs combined with sponge layers is presented for cases where outgoing waves leave the numerical domain of calculation through the open boundary. A reduction of spurious reflections from the numerical open boundaries can be obtained with an irrelevant increase in terms of computational cost. 相似文献
82.
A web-based distributed system for monitoring and forecasting of the marine environment has been developed in line with INfrastructure for SPatial InfoRmation in Europe (INSPIRE) and Global Monitoring for Environment and Security (GMES) recommendations for a European Spatial Data Infrastructure (SDI). This system, called DISPRO, enables integration and distribution of multi-source data from satellites, aircraft, and in situ instruments, as well as results from numerical models. Geographic data and metadata are stored on a set of distributed computer nodes and retrieved and integrated by a web GIS client by means of Open Geospatial Consortium (OGC) Web Map Server (WMS) technologies. A profile of ISO 19115 was developed for metadata handling, using eXtensible Markup Language (XML) as a platform independent encoding mechanism. DISPRO has been demonstrated in six European coastal zone and ocean regions in the spring and summer of 2005. The overall positive experiences of both service providers and end users indicate that the system should be further developed into an operational GMES service. 相似文献
83.
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
84.
《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
85.
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
87.
88.
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
89.
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
90.