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对我国首次用轻飞机拍摄的小像幅航片进行大比例尺测图进行了研究，解决了如何应用小像幅航片进行放大测图，如何消除航片未经压平所造成的系统误差影响，以及倾角过大如何测图等问题，经实验验证，证明小像幅航片可用于大比例尺测图，精度能满足规范要求。 相似文献
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本系统研究了小像幅航摄资料用于小面积大比例尺地形图测绘的可能性以及实施中的技术要求，并用调制传递函数测定了小像幅航摄资料的分解力。 相似文献
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小像幅航空摄影中若干技术要求的研究 总被引：1，自引：0，他引：1
本文系统研究了小像幅航摄资料用于小面积大比例尺地形图测绘的可能性以及实施中的技术要求，并用调制传递函数测定了小像幅航摄资料的分解力。 相似文献
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随着摄影测量技术的发展，用轻型气机装载非量测相机进行航空摄影测量的方法受到了测绘工作者的极大关注，它将具有广阔的应用前景，但也蕴藏着丰富的研究内涵。本文介绍了用日产Bronika SQ-A120型非量测相机对南极中山站所在的拉斯曼丘陵测区1：4万摄影比例尺小像幅航片进行加密的结果。通过用WuCAPS软件的带3个附加参数的自检校光束法区域网平差获得了实地上平面±2.829m，高程±4.973m的加密精度。文章的最后，对小像幅航片摄影测量加密的精度进行了分析，得出了初步结论。 相似文献
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本文介绍的是用轻型飞机是一种有要驾驶的飞机，由汽车运载到航摄地区。可在长２００米空地起落低空飞行摄取大比例尺航摄象片，测制大比例尺地形图的实验研究成果。文中阐述了轻型飞机的特点，组织航摄小面积大比例尺象片的方法，以及对成图检测的精度评定等。 相似文献
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本文介绍的是用轻型飞机是一种有人驾驶的飞机,由汽车运载到航摄地区。可在长200米空地起落)低空飞行摄取大比例尺航摄象片,测制大比例尺地形图的实验研究成果。文中阐述了轻型飞机的特点,组织航摄小面积大比例尺象片的方法,以及对成图检测的精度评定等。通过本文阐述的实验研究,为小测区大比例尺地形图用常规方法成图,对其调机转场难,成本高、提供成果不及时等问题得到了较好地解决。对工业厂矿勘察设计,现有厂矿扩建,城镇规划及地藉测量开辟了一条新路。 相似文献
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根据测区实际情况,采用全数字摄影测量地形图,UltraCam X航摄相机拍摄数码相片,VirtuoZo数字摄影测量工作站立体测图,合理布设像控点,设计满足成图比例尺精度要求的布设方案。对数字摄影航片比例尺的选择,像控点布设方案的确定,外业调绘根据测区实际情况及立体模型测图高程高程精度分析,制定作业方法,最终根据外业实际测量验证方案布设及成图比例尺的精度。 相似文献
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航空摄影比例尺的大小,不但决定成图的精度要求,而且与航空摄影测量的生产成本相关。结合多年生产实践,介绍选择数码航摄比例尺的原则,并对选择航摄比例尺应考虑的因素进行分析,得出在大比例尺数码航摄时,航摄比例尺选择应根据大比例尺航测测图的特点,结合测区的地形条件,在保证测图精度的前提下,本着有利于缩短成图周期、降低成本、提高测绘综合效益的原则进行。 相似文献
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《制图学和地理信息科学》2013,40(2):98-106
The quality of dynamic map symbols plays an important role in the representation of spatial-temporal changes. This paper reports an investigation into the quality of dynamic symbols. To assess the quality of such symbols, a set of traffic flow data is used for the production of different kinds of dynamic maps, with focus on four variables, i.e. size, color, frame rate and display format. Two quantitative measures are used for analysis, i.e. deviation and response time. A set of traffic data is used for the production of dynamic maps for evaluation. The experimental results show that the size is more efficient and more effective than color for dynamic maps with the same frame rate and display format. The most efficient and effective color class number is 10 on the large format display such as 1024 × 768 pixels. And the most efficient and effective size class number is 15 on large format display such as 1024 × 768 pixels. The effective frame rate for dynamic map animation is smaller than that of the general animation on the Internet or Quick Time and AVI format video. The most efficient and most effective frame rate is 3 frames per second in the color expression and 6 frames per second in the size expression. In sum, the effective and efficient value of color, size and frame rate on large format display is less than the value on the small format display. These results suggest the frame rate should be reduced on the small format display. It is hoped that the results from this study will be of help in the design of effective and efficient dynamic map symbols for geographical information visualization. 相似文献
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针对一些通用的空间数据的数据交换格式进行了研究，并就不同数据格式的数据量进行了对比实验。结果表明，在栅格数据中，．bmp格式的数据量最大，.jpg格式和．gif格式的数据量较小；矢量格式的数据量的大小与空间数据的属性有关，在几种常用的矢量格式中，．e00格式的数据量最大。 相似文献
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K. J. Murray 《The Photogrammetric Record》1989,13(73):85-94
In order to realise the full potential of photogrammetry for national map revision, photographic acquisition lead times and, where possible, costs must be significantly reduced. In this paper a review of alternative platform and camera configurations is made and tests are undertaken utilising simulated data and medium format data taken from an existing project. The results suggest that the medium format camera and helicopter combination may have much to offer while the small format camera and microlight aircraft systems have yet to be developed into an effective data acquisition and map compilation system. 相似文献
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图廓整饰是地形图的重要因素。在实际生产中,地形图往往按一定区域进行作业,数量大。如果单幅上图廓,工作量大,而且图幅接合表信息及其他整饰信息容易出错。用程序进行批量上图廓则会减轻工作量,减少不必要的错误。本文介绍DWG格式的大比例尺地形图图廓的生成方法。 相似文献
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G. H. Thomson 《The Photogrammetric Record》1988,12(71):595-603
The use of small format systems for aerial photography as an alternative to employing the more customary larger 230×230 mm format cameras continues to gain acceptance in a number of applications on the basis of the lower operating costs involved. The reduced costs and relative ease of operation with small format systems can attract unskilled operators who, by producing inferior photographic coverage, may delay the more widespread introduction of smaller systems for photo-interpretation and photogrammetric surveys of local sites. Anticipating the need for a flying and photography specification that would serve the needs of all interested parties, a series of laboratory trials were undertaken in conjunction with a literature review to quantify the comparative image quality performance of both large and small format systems. The spatial resolution of a typical small format system was assessed by photographing a low contrast resolution target using a collimator-based system and also by directly recording the target at a predetermined reduction scale. Comparative results between the two methods of evaluation are assessed and a comparison is made with the performance of larger format cameras. 相似文献
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《制图学和地理信息科学》2013,40(1):59-70
In order to create a useful map, the cartographer must select a scale at which the map reader can distinguish features shown on the map and read their labels. However, the choice of scale for a paper map is also constrained by the size of the map sheet and by the cost of working with a large number of sheets. When the feature density pattern allows, space can be conserved by making the map at more than one scale: a small scale suitable for most of the map, while dense features are shown on inset maps at larger scales. Creating inset maps requires the cartographer to make a series of complex, interrelated decisions regarding the most effective overall sheet configuration, which is dependent upon the scale chosen for the main map and how the inset maps are created. The Census Automated Map Production System (CAMPS) applies cartographic logic and density analysis to make these decisions in a fully automated mapping environment. 相似文献
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近年来，传统的媒体网站和新兴的微博、微信等自媒体平台上使用地图配合相关新闻的报道呈明显上升趋势。目前，我国行业主管部门已经建立了相应的软件监管平台，每天都有大量的“问题地图”被系统监测到。但当“问题地图”被监测到之后，系统采用的数据存储方式远不能适应当今大数据时代多维度、立体式数字信息存储、分析的发展潮流。本文通过对态势感知技术的研究，结合互联网“问题地图”监管工作的具体特点，设计了“问题地图”模型的格式及“问题地图”大数据库规格，并以此为基础模拟制定几类“问题地图”态势分析模式，对态势感知模式下的互联网“问题地图”监管工作进行了探究，使国家互联网地理信息监管的相关工作能够得到进一步发展。 相似文献