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1.
《The Cartographic journal》2013,50(3):282-293
Cartographic projects of national importance are often only reported on in local journals which are published in the language of the author or mapping organisation. Owing to this, important maps and map series often stay unknown outside their country of origin. A case in point is the important Carte d’Afrique on a scale of 1∶2?000?000 which, during the last decades of the nineteenth century, was compiled by the French army officer Captain Richard de Régnauld de Lannoy de Bissy. The map made an enormous contribution to the history of cartography of Africa with regard to not only the discovery and exploration of the continent, but also the expansion of colonial control and the political rivalry between European powers. It was an impressive project to be executed by one man and at the time guaranteed a prominent position for the author in geographic and cartographic circles worldwide. Although afterwards superceded by many more accurate maps, Lannoy de Bissy’s map to date remains a lasting witness to the mapping of the ‘dark continent’ and of the fragile, hesitating progress made during the search for geographical knowledge before the advent of aerial photography and satellite imagery. 相似文献
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《The Cartographic journal》2013,50(1):30-39
AbstractAt the end of the eighteenth century, a large-scale map of the Austrian Netherlands and the Prince-Bishopric of Liège was manufactured, covering more or less the current territory of Belgium. The work for this Carte de Cabinet was carried out by artillerists under the guidance of count Joseph de Ferraris, who was commissioned for the task by the Habsburg government. At the time that the map was designed, no modern legend was included. This paper tries to fill that gap by presenting a legend that was constructed more systematically than any of its predecessors. It is based on the structure of the legend of the Topographic Map of Belgium and the CORINE land cover map, making it an easy-to-use tool for modern researchers. The problems encountered during the development of the legend are described, and the link between the Carte de Cabinet and eighteenth-century French cartography as well as with cartographic manuals is also discussed. 相似文献
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The topographic mapping products of airborne light detection and ranging (LiDAR) are usually required in the national coordinates (i.e., using the national datum and a conformal map projection). Since the spatial scale of the national datum is usually slightly different from the World Geodetic System 1984 (WGS 84) datum, and the map projection frame is not Cartesian, the georeferencing process in the national coordinates is inevitably affected by various geometric distortions. In this paper, all the major direct georeferencing distortion factors in the national coordinates, including one 3D scale distortion (the datum scale factor distortion), one height distortion (the earth curvature distortion), two length distortions (the horizontal-to-geodesic length distortion and the geodesic-to-projected length distortion), and three angle distortions (the skew-normal distortion, the normal-section-to-geodesic distortion, and the arc-to-chord distortion) are identified and demonstrated in detail; and high-precision map projection correction formulas are provided for the direct georeferencing of the airborne LiDAR data. Given the high computational complexity of the high-precision map projection correction approach, some more approximate correction formulas are also derived for the practical calculations. The simulated experiments show that the magnitude of the datum scale distortion can reach several centimeters to decimeters for the low (e.g., 500 m) and high (e.g., 8000 m) flying heights, and therefore it always needs to be corrected. Our proposed practical map projection correction approach has better accuracy than Legat’s approach,1 but it needs 25% more computational cost. As the correction accuracy of Legat’s approach can meet the requirements of airborne LiDAR data with low and medium flight height (up to 3000 m above ground), our practical correction approach is more suitable to the high-altitude aerial imagery. The residuals of our proposed high-precision map projection correction approach are trivial even for the high flight height of 8000 m. It can be used for the theoretical applications such as the accurate evaluation of different GPS/INS attitude transformation methods to the national coordinates. 相似文献
4.
ABSTRACTWorld maps can have quite different depictions of reality depending on the projection adopted, and this can influence our perception of the world. In this respect, shape is a significant property that needs to be considered, especially when representing large regions in general-purpose world maps. A map projection distorts most geometric properties (area, distance, direction/angle, shape, and specific curves) and usually preserves a single property or provides a compromise between different properties when transforming terrestrial features from globe to plane. The distortions are mainly classified based on area, distance and direction/angle and analyzed with Tissot’s theorem. However, this theorem offers a local (pointwise) solution, so the distortion assessment is valid at infinitesimal scale (i.e. for very small regions). For this reason, different approaches are required to analyze the distortions at finite scale (i.e. for larger regions). However, there are very few attempts at analyzing and comparing shape distortion of landmasses in world map projections owing to the fact that shape measurement is difficult and usually involves measuring different characteristics. Seeking to fill this gap, in this study, compactness and elongation distortion measures are introduced. In this regard, 16 world map projections are analyzed and compared with these distortion measures in a GIS environment, based on map datasets of continents and countries. An analysis of the effect of the levels of detail of the datasets is also presented. 相似文献
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Motti Zohar 《制图学和地理信息科学》2013,40(6):532-546
ABSTRACTAt the beginning of the twentieth century, a British mapping team led by Captain S. F. Newcombe surveyed and mapped the Negev region, Sinai, and western Jordan. The map was mainly produced for military use. Consequently, it included a network of branched routes, water supplies and facilities, and topographic contours. This study used this map to examine the development of routes in the Negev region between the beginning of and until the end of the twentieth century. First, the individual sheets comprising the study area were pieced together and the accuracy of the map was evaluated. The accuracy found on the Newcombe map was 0.76 mm on the map scale, equivalent to 100.3 m. Route development during the twentieth century was then evaluated by comparing the routes digitized from the Newcombe map to digitized routes on a late twentieth-century map. The results do not reveal tremendous changes in path, shape, or number of routes. Instead, they merely indicate the natural development in their quality. This Historical GIS-based approach provided a useful technique for analyzing and comparing the line segments extracted from historical and modern maps. The implemented approach may also serve other geographical or historical studies aiming to examine the development of branched networks throughout history. 相似文献
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为了鉴定陆地卫星5号系统纠正TM图像产品的精度,我们以1:5万地形图为基准,对四景TM图像作了精度分析。结果表明,系统纠正后的TM图像产品,内部几何精度相当好,有较小的旋转、比例误差。采用一阶多项式即可建立TM图像和地形图之间的几何关系,其误差为1个像元左右。TM图像的大地绝对误差,可通过将整个TM图像沿x,y方向平移的方法来加以校正。 相似文献
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地形图是进行城乡规划、土地利用总体规划的重要依据,对于全面加强土地管理具有重要作用。但是,使用传统方法进行地形图缩编费时费力,本文以某市1∶500到1∶2 000地形图缩编为例,充分利用Auto CAD的二次开发功能、FME Converter平台的数据格式转换和Arc GIS的制图综合工具,采用半自动缩编的方法,提高缩编的工作效率,提供了一种智能化缩编方法的新思路,并介绍地形图中各要素的关键编绘技术及其处理技巧。 相似文献
9.
遥感影像结合RTK绘制中大比例尺地形图的应用研究 总被引：1，自引：0，他引：1
Quick Bird卫星是目前全世界最高分辨率的商用卫星,利用现势的高分辨率的遥感影像,经过精确的变换和正射几何纠正后,得到正射影像,经过判读识别地物,对大比例尺地形图进行快速更新.随着GPS技术快速发展,GPS RTK的精度是完全可以满足在地形图的图根控制中测量的要求.GPS RTK技术以作业速度快、生产组织灵活、实... 相似文献
10.
Umberto Lombardo 《制图学和地理信息科学》2013,40(4):340-347
Quantitative measures of polygon shapes and orientation are important elements of geospatial analysis. These kinds of measures are particularly valuable in the case of lakes, where shape and orientation patterns can help identifying the geomorphological agents behind lake formation and evolution. However, the lack of built-in tools in commercial geographic information system (GIS) software packages designed for this kind of analysis has meant that many researchers often must rely on tools and workarounds that are not always accurate. Here, an easy-to-use method to measure rectangularity R, ellipticity E, and orientation O is developed. In addition, a new rectangularity vs. ellipticity index, REi, is defined. Following a step-by-step process, it is shown how these measures and index can be easily calculated using a combination of GIS built-in functions. The identification of shapes and estimation of orientations performed by this method is applied to the case study of the geometric and oriented lakes of the Llanos de Moxos, in the Bolivian Amazon, where shape and orientation have been the two most important elements studied to infer possible formation mechanisms. It is shown that, thanks to these new indexes, shape and orientation patterns are unveiled, which would have been hard to identify otherwise. 相似文献
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针对特战实训演练中大比例尺军事地形图数据不足、现势性较差的问题,从特战用图需求出发,基于众源地理数据提出了一种快速、高效、经济、准确的大比例尺军事地形图测制方法。首先,介绍了众源地理数据的概念和特点,研究了众源地理数据的来源和获取方法。然后,在顾及军事地形图与民用地形图之间制图表达的差异后,设计了利用众源地理数据绘制大比例尺军事地形图的工艺流程。最后,基于ArcMap,绘制了某地1∶1万军事地形图并进行实验验证和精度分析。实验结果表明,该方法既可有效提高作业效率,又能满足成图精度要求,可为军事教学训练、指挥员用图决策提供重要参考。 相似文献
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于杰;张淑萍;于爱洁 《东北测绘》2013,(4):179-180,183
制作影像地形图是一种地图新产品的有益尝试。在矢量线划地形图上叠加影像,影像丰富的纹理和色彩信息增强了地形图在地形地貌方面信息的表达,同时在影像上叠加一定的矢量要素,又弥补了单纯影像不能定量和指示性欠缺的不足。在生产实践中,该产品的作业方法同传统地形图制作有区别又有联系。针对这一新产品,本文提供了一种利用Adobe Illustrator CS2制作1∶50 000影像地形图的生产工艺。 相似文献
15.
Gottfried Gerstbach 《Journal of Geodesy》1988,62(4):541-563
The short wavelength geoid undulations, caused by topography, amount to several decimeters in mountainous areas. Up to now
these effects are computed by means of digital terrain models in a grid of 100–500m. However, for many countries these data are not yet available or their collection is too expensive.
This problem can be overcome by considering the special behaviour of the gravity potential along mountain slopes. It is shown
that 90 per cent of the topographic effects are represented by a simple summation formula, based on the average height differences
and distances between valleys and ridges along the geoid profiles,
δN=[30.H.D.+16.(H−H′).D] in mm/km, (error<10%), whereH, H′, D are estimated in a map to the nearest 0.2km. The formula is valid for asymmetric sides of valleys (H, H′) and can easily be corrected for special shapes. It can be used for topographic refinement of low resolution geoids and for
astrogeodetic projects.
The “slope method” was tested in two alpine areas (heights up to 3800m, astrogeodetic deflection points every 170km
2) and resulted in a geoid accuracy of ±3cm. In first order triangulation networks (astro points every 1000km
2) or for gravimetric deflections the accuracy is about 10cm per 30km. Since a map scale of 1∶500.000 is sufficient, the method is suitable for developing countries, too. 相似文献
16.
随着社会的发展和科技的进步,各种先进的测量设备也不断涌现出来。近几年来,无人机航测在测绘行业中发展非常迅速,尤其是在地形图测绘中。中小比例尺的地形图测绘基本上都采用航测的方法进行,但是免像控无人机在大比例尺地形图测绘生产过程中仍然存在很多问题。本文以泰安某地区1∶500地形图测绘项目为例,通过对航线设计、影像处理方面的分析,为提高作业效率以及地形图成果精度提供了有效的手段。 相似文献
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利用IKONOS立体像对提取DEM精度的实验 总被引：4，自引：1，他引：3
由于IKONOS不提供基于共线模型所需的卫星星历参数,而提供基于有理函数(RPC)的近似模型,因此点位精度和高程精度主要由RPC模型精度来决定。直接使用RPC模型对标准几何校正产品进行DEM提取,这种精度不能满足高精度制图的要求。本文讨论了基于IKONOS立体像对提取翠华山地区的DEM及其精度情况。为提高精度,采用高精度GPS仪(Mobile Mapper CX高程精度达亚米级)野外采集控制点,对RPC模型进行修正。对比分析结果表明DEM精度明显提高,仅需少量的控制点,DEM和正射影像均满足15∶000比例尺地形图和遥感平面制图要求。 相似文献
18.
针对倾斜无人机影像在三维重建与大比例尺测绘产品生产中的精度难以满足问题,本文首先对连接点进行全局抽稀与局部抽稀相结合的方式对稀少控制点进行补充,然后进行高精度GPS辅助区域网平差,最后利用倾斜无人机影像进行三维重建并进行精度分析。结果表明,在生成的三维模型上编辑生成1∶500地形图的方法满足1∶500地形图成图精度要求。 相似文献
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海岸带地区陆海图的差异分析 总被引：6，自引：0，他引：6
海岸带是影响人类活动的重要地带.随着海洋经济的发展,海岸带专题图的需求日益增加.详细介绍了目前海岸带地区地形图和海图表示方法的各种差异,分析了产生这些差异的根本原因;阐述了消除地形图和海图差异的办法即新建海岸带地形图,编制海岸带地形图测量和编绘规范,编制海岸带地形图图式,统一海岸带地形要素的表示内容和表示方法.在此基础上根据不同的需要测绘海岸带地形图,为经济建设和社会发展提供有力的技术支持. 相似文献
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顾及非格网数据考虑地形改正的GPS水准高程拟合 总被引：2，自引：0，他引：2
系统地分析了目前常用的确定高程异常的重力法和几何法在山区GPS网中的局限性。提出了一种顾及非格网数据考虑地形改正的GPS水准高程拟合法,同时对利用非格网数据和内插格网概略大地高所造成的影响也进行了估计。建议在地形起伏较大地区,借助地形图内插部分特征点作为虚拟GPS观测值,参与整体内插计算,有助于提高计算精度。 相似文献