共查询到18条相似文献，搜索用时 91 毫秒
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简要介绍了琼州海峡500 kV海底电缆地形地貌特点及保护方式,分析了侧扫声呐及多波束检测的基本原理,对侧扫声呐在海底电缆裸露及悬空检测的原理进行了重点阐述。结合海南联网500 kV海底电缆近几次检测数据,通过侧扫声呐地貌检测结果,重点对海底电缆裸露情况、抛石坝及铸铁套管保护状况、海底电缆周围异常进行了分析,能够正常检测出海底电缆的裸露、抛石坝的坍塌及周围异物等异常情况。通过多波束地形检测结果,分析了海底电缆路由区域整体地形状况及抛石坝整体状况、通过Kriging插值方法生成不同的DEM(数字高程模型,Digital Elevation Model),分别从宏观和微观角度对海底电缆路由区域地形冲淤变化进行了分析,并对沙波稳定性进行了分析。结论认为,部分区域地形冲刷严重,容易造成海底电缆裸露、悬空,需要及早关注并采取防冲刷措施。 相似文献
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基于多源水深数据融合的海底高精度地形重建 总被引：2，自引：0，他引：2
本文在研究多源水深数据构建技术的基础上,分析了张力样条插值算法和“移去-恢复”法的多源水深数据融合处理技术,基于该方法选取实验区,利用多波束、单波束、历史海图等多源水深数据进行高精度海底地形融合试验,并针对多源水深融合技术缺少误差评估的现状,利用split-sample方法对融合结果进行水深不确定性评估,形成融合结果的可靠性空间分布。结果表明该方法无论是在数据稀疏区还是高密度区都达到了较好的融合效果,既保留了高分辨率水深数据的细节信息,又较真实的反映了研究区海底地形特征,且构建的海底地形精度可靠,误差百分比集中在0.5%。本文整套数据融合和结果评估方法可为多源水深数据融合的海底高精度地形构建提供借鉴和参考。 相似文献
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海洋测绘数据信息化是构建智慧海洋的基础, 而海底地形数据是海洋测绘数据中的重要内容。为更加便捷和高效地 管理与利用地形数据, 本文结合工程实际需求, 研发了海底地形数据管理平台。首先, 基于海底地形数据的特点, 提出多分 辨率海底地形组织模型, 对不规则区域的海底地形进行多分辨率模型构建, 实现了对多波束实测数据的组织管理; 在此基础 上, 提出了多尺度海底地形分级渲染优化算法与海底地形数据空间截取算法, 利用分级渲染与数据裁剪算法实现对海底地形 数据的可视化表达预览和选取服务; 最后, 以典型的多波束测深数据为例, 基于研发平台完成了数据从存储 、组织管理到可 视化预览选取的一体化管理与服务, 验证了本文算法的可靠性与实用性, 同时可为海底地形数据管理服务提供一定参考。 相似文献
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基于2004—2010年渤海海底地形地貌调查资料,结合前人对渤海海底地形的认识,对渤海海底地形5个区(辽东湾、渤海湾、莱州湾、渤海中央盆地和渤海海峡)的地形及微地形,进行了全面的分析描述。并与1985年出版的渤海地形图进行比较,寻找渤海地形近几十年来的变化并分析其原因。分析表明:渤海海底地形平缓,从辽东湾、渤海湾和莱州湾三个海湾向渤海中央盆地及东部渤海海峡倾斜,平均水深18m;由于环境变化和人类活动,导致部分近岸海域的水深比40多a前的水深变浅,而渤海中央盆地发生侵蚀,水深加深。 相似文献
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传统潮滩地貌的研究方法难以刻画潮滩的微观地貌特征,地面激光扫描仪(TLS)的应用为潮滩地貌的研究提供了新的切入点,然而目前关于TLS在潮滩地貌研究中鲜有报道。以江苏东灶港海岸一段潮滩地貌为研究对象,基于野外扫描数据,对扫描区域的点云数据进行精度评估,并尝试利用反距离加权插值(IDW)与克里金插值(Kriging)方法构建了潮滩地貌的数字高程模型(DEM)。研究结果表明:(1)通过点云数据构建的DEM数据能够实现潮滩地貌的定量模拟;(2)利用IDW插值可以便捷高效构建潮滩海量数据点的DEM;(3)利用TLS量化短期地貌变化如潮汐沉积旋回效果并不好。本研究可为利用TLS在潮滩微观地貌中的量化研究提供参考。 相似文献
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针对目前"数字海底"建设中存在海底调查数据集成管理与三维可视化表达不足等问题,本文采用GIS技术,以黄河水下三角洲埕北海域为研究对象,利用地理空间数据集成理论与三维建模方法,建立了埕北海域三维海底空间数据库,实现了研究区域地形数据、地层数据、钻孔数据、表层沉积物数据的有效组织管理与可视化,并在此基础上,采用ArcGIS Engine 10.0,结合.NET平台,在Visual Studio 2010开发环境下,利用C#语言进行了二次开发,实现了基于C/S (Client/Server)架构的三维海底虚拟仿真系统的开发,设计了一套面向埕北海域的三维海底虚拟仿真原型系统。 相似文献
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海底地形匹配导航技术可实现自主水下机器人(Autonomous Underwater Vehicle,AUV)长时间的水下精确导航。质点滤波器(Point-Mass Filter,PMF)是实现 AUV 精确海底地形匹配导航的重要方法,但质点权重计算过程中需要寻找空间分布不规则的实测地形数据点与网格化先验地形图数据点间空间对应关系,造成大量计算消耗,严重影响了地形匹配导航算法实时性能。提出一种海底地形匹配高效质点滤波导航方法,通过构建伪输入高斯过程(Sparse Pseudo-input Gaussian Processes,SPGPs)模型,实现实测海底地形数据高效、精确网格化插值过程,并根据 SPGPs 方法提供的插值置信度实现网格化概率地图构建;搭建质点滤波器算法框架,提出适用于概率地图的质点权重计算过程,通过考虑网格化地图不同节点插值置信程度差别,提高地形匹配导航精度。于青岛中沙礁展开海上数据获取试验,并利用海试数据完成算法回放式仿真验证。试验结果证明,所提出网格化插值方法可实现高精度、高效地形深度插值过程,所提出海底地形匹配高效质点滤波导航方法可为 AUV 在线提供精确导航结果,且实时导航圆概率误差小于 3 m。 相似文献
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To address the limitations of current methods to control and adjust the accuracy of depth models and relatively low accuracy, a quantitative method to control and adjust the accuracy of adaptive grid depth modeling is proposed. First, uncertainties in source data and interpolated depths are estimated, and the representation uncertainty derived from finite and discrete points representing the continuous seafloor surface is analyzed. Second, mean vertical uncertainty in an arbitrary given area is calculated. Finally, interpolation of the depths at grid nodes from source data and the distribution framework of the grid nodes are optimized in each local area, and an adaptive grid depth model is created according to the expected accuracy. The experimental results demonstrate that (1) the proposed method can control and adjust the accuracy of the depth model in each local area such that the accuracy of the constructed model meets the requirements of the expected index as closely as possible and (2) the proposed method can improve the accuracy of the depth modeling by optimizing the interpolation and distribution of the grid nodes. 相似文献
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Modeling of long-wavelength gravity anomaly is crucial for bathymetry inversion with a gravity-geologic method. We propose a new method, named as iGGM, to approximate the long-wavelength gravity anomalies by using a finite element method based on an adaptive triangular mesh which is constructed by uneven control points. The mesh size is suitably controlled to ensure that there are several control points in each grid. By using iGGM, the bathymetry in the South China Sea (Test Area #1: 112°E–119°E, 12°N–20°N) and East China Sea (Test Area #2: 125°E–130°E, 25°N–30°N) is estimated. The performance of the method was evaluated by comparing the predictions with Earth topographical database 1 (ETOPO1) model and shipborne depths in the test points. Results show that the depths derived by iGGM have a strong correlation with the shipborne depths. In the test points, the mean values of their differences are smaller than 10 m. The standard deviations of their differences are smaller than 120 m and their correlation is stronger than 0.98. Meanwhile, the results provided by the iGGM model are comparable with that obtained by the ETOPO1 model, e.g., the differences between iGGM and ETOPO1 models in test points for Test Areas 1 and 2 are 116 and 70 m in standard deviation, respectively. 相似文献
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Nathaniel G. Plant Kacey L. Edwards James M. Kaihatu Jayaram Veeramony Larry Hsu K. Todd Holland 《Coastal Engineering》2009
Nearshore wave and flow model results are shown to exhibit a strong sensitivity to the resolution of the input bathymetry. In this analysis, bathymetric resolution was varied by applying smoothing filters to high-resolution survey data to produce a number of bathymetric grid surfaces. We demonstrate that the sensitivity of model-predicted wave height and flow to variations in bathymetric resolution had different characteristics. Wave height predictions were most sensitive to resolution of cross-shore variability associated with the structure of nearshore sandbars. Flow predictions were most sensitive to the resolution of intermediate scale alongshore variability associated with the prominent sandbar rhythmicity. Flow sensitivity increased in cases where a sandbar was closer to shore and shallower. Perhaps the most surprising implication of these results is that the interpolation and smoothing of bathymetric data could be optimized differently for the wave and flow models. We show that errors between observed and modeled flow and wave heights are well predicted by comparing model simulation results using progressively filtered bathymetry to results from the highest resolution simulation. The damage done by over smoothing or inadequate sampling can therefore be estimated using model simulations. We conclude that the ability to quantify prediction errors will be useful for supporting future data assimilation efforts that require this information. 相似文献
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针对浅海测深的数据特点和应用需求,以我国南海甘泉岛为例,研究了利用ICESat-2(Ice,Cloud,and Land Elevation Satellite-2)激光卫星数据和光学遥感影像开展主被动融合水深测量的方法。首先通过信号点提取、水面/水底识别、水下点折射改正等步骤处理ICESat-2数据,获得水深值,随后以激光点作为控制,计算光学水深反演模型参数,最后由点及面地获取大范围高精度水深。实验表明,甘泉岛区域主被动融合测深中误差优于1.30m,基于激光卫星数据的主被动融合测深方法能够为浅水水深测量提供新手段。 相似文献
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We present a porous medium approach to representing topography, and a new algorithm for the objective interpolation of topography, for use in ocean circulation models of fixed resolution. The representation and algorithm makes use of two concepts; impermeable thin walls and porous barriers. Impermeable thin walls allow the representation of knife-edge sub-grid-scale barriers that block lateral flow between model grid cells. Porous barriers permit the sub-grid scale geometry to modulate lateral transport as a function of elevation. We find that the porous representation and the resulting interpolated topography retains key features, such as overflow sill depths, without compromising other dynamically relevant aspects, such as mean ocean depth for a cell. The accurate representation of the ocean depth is illustrated in a simple model of a tsunami that has a cross-basin travel time very much less dependent on horizontal resolution than when using conventional topographic interpolation and representation. 相似文献