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1.
基于GDCORS的网络RTK技术在海岸线修测中的应用 总被引：2，自引：0，他引：2
介绍网络RTK技术在海岸线修测中的应用,并以广东省海岸线修测为例,详细说明基于GDCORS的网络RTK技术在海岸线修测中的作业方法及所起的作用,与常规RTK相比具有一定的优越性,同时进一步对网络RTK技术误差源及解决方法进行分析。 相似文献
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结合陆地勘界和海域勘界要求,研究GPS技术在行政区域勘界中的应用,并针对GPS、RTK技术的局限性,提出几种特殊的勘界方法。 相似文献
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提出了一种基于纸质地形图的单像地形图数字修测方法.它能在不具有矢量地形图的地区,根据新摄取的航摄像片直接对原有地形图分版图的扫描影像进行修测,然后用绘图输出设备输出修测后的像素地图,或用于GIS中相应数据的更新. 相似文献
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提出了一种基于纸质地形图的单像地形图数字修测方法,它能在不具有矢量地形图的地区,根据新摄取的航摄像片直接对原有的地形图分版图的扫描影像进行修测,然后用绘图输出修测后的像素地图,或用于ＧＩＳ中相应数据的更新。 相似文献
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提出数字地形图快速修测的概念并论述其意义,分析了可用于数字地形图快速修测的信息源,论述了实现数字地形图快速修测的关键技术与实施途径. 相似文献
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1:10000地形图作为基础测绘的重要组成部分,在国民经济发展中发挥着举足轻重的作用.如何高效、高质量地完成地形图修测工作,一直受到测绘工作者们高度重视.利用传统测绘技术进行地形图修测工作,往往费时费力,成本较高;效率较高的无人机航测技术也有它自身的局限性.近年来,国家一直致力于推广应用高分二号卫星,因此本文研究探讨了将高分二号卫星影像应用于1:10000地形图修测工作的可行性,并得出了比较可靠的结论. 相似文献
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基于IKONOS卫星影像进行地形图修测的方法研究 总被引：3，自引：0，他引：3
本文以项目试验为基础,将经过融合、校正等处理的IKONOS卫星影像数据叠加到已有地图数据上进行地形图的修测,研究利用现势性强的高分辨率卫星影像进行规模化修测1∶10000、1∶5000甚至更大比例尺地形图的技术路线。 相似文献
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城市大比例尺地形图动态修测的质量控制 总被引：1，自引：0，他引：1
从深圳市1：1000地形图动态修测的实践出发，阐述了城市大比例尺地形图动态修测质量控制的基本方法和内容，以工程监理制与生产单位的质量控制体系的结合，实现了对地形图动态修测质量的控制。 相似文献
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The accuracy of ocean tide loading (OTL) displacement values has long been assumed to be dominated by errors in the ocean
tide models used, with errors due to the convolution scheme used considered very small (2–5%). However, this paper shows that
much larger convolution errors can arise at sites within approximately 150 km of the coastline, depending on the method used
to refine the discrete regularly spaced grid cells of the ocean tide model to better fit the coastline closest to the site
of interest. If the local water mass redistribution approach is implemented, as used in the OLFG/OLMPP software recommended
in the IERS 2003 conventions, OTL height displacement errors of up to around 20% can arise, depending on the ocean tide model
used. Bilinear interpolation only, as used in the SPOTL and CARGA softwares for example, is shown from extensive global and
regional comparisons of OTL displacement values derived from the different methods and softwares to be more appropriate. This
is verified using GPS observations. The coastal refinement approach used in the OLFG/OLMPP software was therefore changed
in August 2007 to use bilinear interpolation only. It is shown that with this change, OTL displacement values computed using
OLFG/OLMPP, SPOTL and CARGA invariably agree to the millimetre level for coastal sites, and better than 0.2 mm for sites more
than about 150 km inland. 相似文献
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The error contributions within the ocean tide loading (OTL) convolution integral computation were determined to be able to estimate the numerical accuracy of the gravity OTL values. First, the comparison of four OTL programs by different authors (CONMODB, GOTIC2, NLOADF and OLFG/OLMPP) at ten globally distributed gravity stations using exactly the same input values shows discrepancies between 2% and 5%. A new program, called CARGA, was written that is able to reproduce the results of these programs to a level of 0.1%. This has given us the ability to state with certainty the cause of the discrepancies among the four programs. It is shown that by choosing an appropriate interpolation of the Green’s function, refinement of the integration mesh and a high-resolution coastline, an accuracy level of better than 1% can be obtained for stations in Europe. Besides this numerical accuracy, there are errors in the ocean tide model such as a 1% uncertainty in the mean value of the sea-water density and the lack of conservation of tidal water mass, which can produce offsets of around 0.04 μgal. 相似文献
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以弯曲骨架线为化简指标的海岸线综合方法 总被引：1，自引：0，他引：1
针对海岸线综合中以弯曲高度和弯曲深度为化简指标的不足,提出了以弯曲骨架线为指标的综合方法。在基于曲线单调段的弯曲识别的基础上,通过弯曲部位三角网的构建提取了弯曲骨架线。结合＂扩陆缩海＂原则进行了海岸线综合实验,验证了该方法在保持海岸线形态特征方面的有效性与可行性。 相似文献
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随着社会经济的高速发展,沿海经济带正发生着日新月异的变化,海岸线环境发生了巨大改变。利用遥感技术不受时间、空间限制的特点,研究海岸线变化监测,有利于掌握海岸线分布情况,监测海岸线沿线生态环境。本文是基于多时相遥感影像,开展辽宁省大陆海岸线变化监测研究。 相似文献
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受海岸带区域自然环境变迁与人类开发活动的综合影响,海岸线不断发生剧烈变化。发现海岸线变化并将变化前后的岸段进行匹配,对分析海岸线变化至关重要。针对传统空间分析工具难以直接确定不同时相变化岸段的对应关系的问题,本文引入单链曼延编号的思想对海岸线变化进行快速匹配,并按照"一对一"和"多对多"两种变化岸段匹配关系提出了位置变迁、类型转移、消失及新增等海岸线变化类型的判断公式,设计并实现了结合单链曼延编号的海岸线变化匹配与信息存储方法。试验证明,该方法能快速准确地实现海岸线变化匹配,并能很好地解决多对多变化岸段匹配的问题。 相似文献
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Beach heights and tidal variation have large impacts on the accuracy of estimates of coastline position and its historical changes of a wider and flatter beach based on remote sensing data. This study presents an approach to analysis of waterline movement based on the beach slope, estimated from two effective images with Landsat images data. Two images acquired at different stages of the tide were processed to delineate accurately the position of the waterline. Then waterlines were assigned heights using elevations predicted by a two-dimensional non-linear tidal assimilation model. Beach slope can be calculated piecewise using the heighted shorelines based on the equiangular triangle theory. The positions of the national tidal height datum coastline can be obtained by the beach slope calculation method to accurately monitor the changing of coastline. A change in the coastline of the southwest tidal flat of the Yellow River delta, from Tianshuigou to the Xiaoqing River mouth, was detected by combining field measurements of profiles and bathymetric data. The root mean squared error (RMSE) of the calculated slope of the intertidal zone was one order of magnitude less than the measured slope. The minimum error of self-consistency check is 0.2%. The RMSE between the coastlines estimated by the proposed method and those surveyed data varies from 53.98 m to 217.72 m. It is shown that this method is more suitable for the two years and over the time scales of shoreline change monitoring. To assess erosion/accretion patterns in the tidal flat, and the controlling factors, the volume of the beach was investigated as a possible indicator. The accepted coastline position and changes in the beach volume were used to monitor the changing pattern of accretion and erosion along the coast southwest of the recent Yellow River mouth. 相似文献
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This study describes a method to map shoreline indicators on a sandy beach. The hypothesis is that, on this beach, spectral albedo is predominantly determined by moisture content and water lines can, therefore, be detected as albedo contrasts. A laboratory experiment is performed to relate moisture content to image albedo, and supervised edge detection is subsequently used to map the shoreline indicators with remote sensing imagery. The algorithm is tested with data from visible, near-infrared and shortwave-infrared wavelength regions. These results are compared to shoreline indicators obtained by a field survey and a shoreline indicator derived from a digital elevation model. Both the water line present when the imagery was acquired, as well as the maximum extent of the last flood, can be detected as a single edge. Older high water lines are confused with the last high water line and appear dispersed, as there are multiple debris lines present on the beach. The low water line, usually in saturated sand, also appears dispersed due to the presence of channels and troughs. Shorelines are constant moving boundaries, which is why shoreline indicators are used as a proxy. Unlike a mathematical indicator that is based on an elevation model, our method is more sensitive to the dynamic nature of shorelines. Supervised edge-detection is a technique for generating reproducible measurements of shoreline indicator positions over time, and aids in the monitoring of coastline migration. 相似文献
18.
由于数字海图中海岸线的重要性及对海图自动综合的迫切需求,本文针对国内外一些对线状目标的自动综合方法中存在的弊端,提出了一种新的海岸线自动综合模式——空间图形的表达、识别与综合。并通过试验验证了该方法的有效性及可行性。 相似文献
19.
针对当前常用的低潮线提取方法不能适应较大区域范围的现状,提出一种基于曲面求交的低潮线提取方法。首先,在顾及潮滩带状分布特点的基础上,采用单向分区策略构建潮滩数字高程模型;然后,综合利用验潮站和网格潮汐模型计算的低潮面值,采用TCARI (the tidal constituent and residual interpolation)方法,构建曲面形态（连续无缝）的沿岸低潮面模型;最后,对所构的两个模型进行曲面求交,提取沿岸低潮线。试验结果表明,当提取低潮线的区域较大时,所提方法能明显提高低潮线的提取精度。 相似文献