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1.
A brief review paper focuses on Soviet strategies for the use of space imagery, particularly photographic products (1:2,000,000 to 1:4,200,000 scale) from manned spaceflights, in the revision of small-scale general reference maps. Principles for the interpretation and mapping of basic map elements appearing on space photographs are outlined. Space photographs provide for reduction in time spent in map editing and the more correct analysis of the reliability of information and its generalization. A technology of map revision based on the joint use of original photographs and photomaps, with the transfer of revisions from photomaps to map originals, is proposed. Translated from: Geodeziya i kartografiya, 1986, No. 8, pp. 29-33.  相似文献   

2.
The author outlines a method for quantitative analysis of the completeness of information presented on maps of varying scale, i.e., for determining, upon reductions in scale of an original map A, what magnitudes of loss in graphic detail will result in derivative maps B, C, D that are of equal relative completeness to the original. Empirical formulae are derived which describe intensities of selection typical of maps devoted to particular topics (stream networks, urban socioeconomic indices, etc.) and graphic methods are described which can be used to determine scale denominators at which specific reductions in the number of features can occur without losses in “completeness” or, conversely, the number of particular kinds of features that can be eliminated on maps (or portions of maps) upon reductions in scale without losses in completeness. Translated from: Vestnik Moskovskogo Universiteta, geografiya, 1985, No. 5, pp. 17–23.  相似文献   

3.
基于CAD的高精度矿图数字化研究   总被引:1,自引:0,他引:1  
对矿图信息化技术现状及煤矿地质数据的特征进行分析,在比较当前数字化方法的基础上,设计出一种基于煤矿原始导线控制点展绘的数字化方案,以某煤矿为例进行方案实施。同时研究了从原始数据电子化、电子数据导入、光栅图像处理等方面减小误差的方法,最大限度地提高了数字化精度。完成了矿图转变为计算机存储、编辑和输出图件的任务。为矿山企业提供快速、准确的决策依据。  相似文献   

4.
Visualization of reliability in spatial data has been the subject of considerable recent research activity. Animation has been suggested as one method to achieve this, and its application to various measures associated with class-area maps (classified satellite images and soil maps) has been discussed elsewhere. Animation is achieved by randomly selecting a location and then assigning it to a different map unit (cover or soil type) according to the information on the reliability associated with the original map or map units. In this article the same basic method is extended to mapping locational reliability in dot maps and surface error in a digital elevation model (DEM). In the former case, the dots, which are randomly located in the first place, are randomly relocated so that any meaningless positional information implicit in the location of the dots is lost while the meaningful information (the number of dots within a region) remains constant. In the DEM, animation uses a random field as an error surface, based upon the root mean squared error (RMSE). The amount of error at a location is constantly changed, giving no impression that the elevation is precisely known. The ability to vary the spatial autocorrelation within the error field provides a graphic illustration that the usual RMSE is not a sufficient method for the reporting of error in spatial databases. In both examples animation of reliability is believed to make a novel, but appropriate, use of the computer in cartography.  相似文献   

5.
本研究的目的是探讨利用遥感影像数据,对县级土壤调查资料进行地区级汇总的制图工作方法。我们依据的制图综合原则是:(1)以现有的土壤图为基础,充分尊重原图上的界线,主要以土层界线重新综合;(2)研究并搞清各种土壤分布规律和它们之间的组合规律,然后进行归并和区分;(3)参照卫星影像特征和判读标志,对某些明显与实地不符之处,以影像和实地调查资料进行修正,有些土壤类型以组合形式表达。本文对利用遥感数据进行制图综合的工作方法进行了详细描述,其中包括:制图单元的综合和比例尺的改变,底图的制作和利用卫星影像对综合后的土壤图进行编制等。研究结果表明,此种方法与常规方法比较,特别是对有一定物质和技术条件的单位(如省级),不仅在土壤调查中,而且在资源调查中皆可采用此种编图技术,收到节省人力、物力和时间的效果。  相似文献   

6.
借助于微型计算机而建立的地图图形工作站其目的在于完成数字化地图生产,即从地图数据的获取、管理、编辑、更新到图形输出等一系列过程。而地图数字化子系统则是该工作站上完成数据获取这一最初也是最重要过程的软件系统。文中介绍了笔者研制的地图图形工作站上的地图数字化子系统。该系统是在自行设计和研制的地图图形工作站的总框架下完成的,现已具备数字地图产业化生产能力,能有效地配合工作站完成数字地图的生产。同时,该系统对于不同的数据获取途径以及诸如我国地(形)图的独特要求(如汉字注记的处理)等方面有良好的适应性。  相似文献   

7.
A method of compiling lunar thematic photomaps is described, in which telescopically derived photometric data, representing the map theme of albedo variation, is portrayed on a topographic base map prepared from scanner data obtained from a space probe. Digital image processing is employed in a wide range of tasks including data averaging and filtration, and grid and scale transformation. Two maps, representing different versions of final output, are provided: a map with albedo variation displayed according to the shaded-isoline technique, and one in which numerical values are printed over a grid of control points. Translated from: Geodeziya i kartografiya, 1985, No. 1, pp. 38-44.  相似文献   

8.
The authors address a range of issues connected with the visual representation and interpretation of statistical data on maps. Attention is focused on common behaviors of map users in determinations of various characteristics of map symbols. Results are reported from experiments testing the relationship between the accuracy of obtaining quantitative information on a map with the total number of symbols and number of scale levels [size classes] employed, the use (or non-use) of color in the symbolization scheme, etc. Translated by Larry Richardson, Los Angeles, CA 90039 from: Izvestiya Vsesoyuznogo Geograficheskogo Obshchestva, 1989, No. 4, pp. 345–351.  相似文献   

9.
The main purpose to develop a Map Graphic Workstation on thewidely used micro-computer is that by it the whole processing of map data fromcapturing,managing,editing,updating to graphic outputting can be realized.Map Digitization System(MDS)is the software system to deal with the initial andalso the most important processing.In this paper,the authors introduce a MDSon a micro-computer based Map Grphic Workstation that has been qualitified forthe producation of digital map.Since the system is designed totally independentlyand in the general frame of the Map Graphic Workstation,the capturing and man-aging and other processings for map data are in an integral manner,in which theproducation of digital map can be fulfilled conveniently.At the same time,thesystem is flexible for function extension and widely applicable to the data from dif-ferent sources and with different information characterisitcs(e.g.,the processingof Chinese characters on map).  相似文献   

10.
A team of Russian geographers describes the development of a program for mapping land use/resource development and the condition of the environment in Russia's Buryat Republic. Three ecological maps recently compiled in the Republic, using a single cartographic base and employing standardized methods, are described. The last such map is a map of environmental use that reflects both a resource-development and an environmental-protection perspective. The article includes detailed examples of the legend of the latter map. Translated by Edward Torrey, Alexandria, VA from: Geografiya i prirodnyye resursy, 1998, No. 3, pp. 23-29.  相似文献   

11.
Heterochronous multispectral imagery from the “Fragment” scanner is used to identify and map a series of “natural-agricultural complexes,” or agricultural landscapes, of southern European Russia. Interpretation is based on imagery in the green, orange, red, and near-infrared zones of the spectrum (0.5-1.1 μm). Interpretation keys and other information designed to facilitate feature discrimination (optimal wavelengths, best seasons for imagining) are provided in many instances. Natural landscape and soil erosion maps are also compiled from the imagery, which supply information (an optimal crop rotation scheme and needed reclamation measures) used on the agricultural landscape map. Translated from: Vestnik Moskovs-kogo Unlversiteta, geografiya, 1985, No. 2, pp. 34-41.  相似文献   

12.
A computer-efficient global data file, which contains digitized information that enables identification of a given latitude/longitude defined point as over land or over water, was generated from a data base which defines the world's shoreline. The method used in the generation of this land-sea boundary data map and its data structure are discussed. The data file was originally generated on a Control Data Corporation(CDC) computer, but it has been transported to other computer systems, includingIBM, DEC/VAX, UNIVAC and Cray computers. The land-sea boundary map also includes information on islands and inland lakes. The resolution of this map is 5′×5′ or an equivalent of9 km square surface blocks at the equator. The software to access this data base is structured to be easily transportable to different computers. This data base was used in the generation of the Seasat Geophysical Data Record(GDR) to identify whether a spaceborne radar altimeter measurement was over-land or over-ocean.  相似文献   

13.
1∶10 000比例尺的局基本任务已由图面入库两套数据资料发展成为图库一体化的数据资料。在方便作业的同时,更加方便资料的储存及查询等工作。文章主要对于EPS平台下1∶10 000图的数据编辑、数据入库工作以及数据质检工作进行简单论述。  相似文献   

14.
The author, in a review of Ye. Ye. Shiryayev's book, Cartographic Presentation, Transformation, and Analysis of Geoinformation, addresses several issues in the automation of cartography—in particular what he perceives as a growing tendency to underestimate the importance of understanding the information being portrayed on maps. A formalistic (strictly quantitative) view of generalization that focuses on preservation or minimization of the loss of information on an initial map ignores the potential for the creation of new knowledge through the abstraction and elimination of information about lower-order systems. Salishchev criticizes Shiryayev's method of “raster digitizing” on such formalistic grounds, and because of its lack of visual quality and purported indiscriminate application within cartography. Shiryayev's reply to Salishchev's comments appears in the following paper of this issue. Translated from: Geodeziya i kartografiya, 1985, No. 11, pp. 59–61.  相似文献   

15.
孙悦 《东北测绘》2012,(3):190-193
1:10000比例尺的局基本任务已由图面入库两套数据资料发展成为图库一体化的数据资料。在方便作业的同时,更加方便资料的储存及查询等工作。文章主要对于EPS平台下1:10000图的数据编辑、数据入库工作以及数据质检工作进行简单论述。  相似文献   

16.
ABSTRACT

This research examines how people subjectively perceive the disclosure risk of a map using original data collected in an online survey with 856 participants. The results indicate that perceived disclosure risk increases as the amount of locational information displayed on a map increases. Compared to point-based maps, perceived disclosure risk is significantly lower for kernel density maps, convex hull maps, and standard deviational ellipse maps. The results also revealed that perceived disclosure risk is affected by map scale and the presence of information of other people on a map. For geomasking methods, perceived disclosure risk decreases as aggregation level increases and as relocation distance increases. However, aggregation methods (point to polygon) are more effective in preventing the re-identification of individuals when compared to relocation methods (point to point). Lastly, the perceived disclosure risk of a map that displays socially-vulnerable people is significantly higher than that of a map that displays non-vulnerable groups. Specifically, a map displaying the private locations of elementary school students has the highest perceived disclosure risk. Based on the results, a set of geoprivacy protection guidelines for mapping people’s private locations to minimize people’s perceived disclosure risk is proposed. Implications for mapping infectious diseases like the COVID-19 are also discussed.  相似文献   

17.
The recent study and classification of over 200 cadastral maps created in the nineteenth century in Catalonia have provided a valuable source of information about the agricultural landscape country’s past, but by linking them with data recorded in tax books known as amillaramientos, it is possible to gain a better knowledge of the past. By applying this method to the 1861 cadastral map of Horta and its corresponding amillaramiento, a planimetric map showing the land use distribution in the town was created. The resulting land use map was subsequently overlaid on top of a digital elevation model to create 3D visualizations which show the altitudinal distribution of crops and other features. Finally, the article explores a way of distributing the results online, making them accessible to the public and increasing the research impact of future findings. Therefore, the method described in this article allows the systematic recreation and distribution of past landscapes by using Catalan cadastral maps of the nineteenth century, something which can help enrich the scientific knowledge of many disciplines.  相似文献   

18.
纸质地图制作和地理信息生产构成数字地图制图中两大相对独立的研究领域,在分析两者异同的基础上,设计了纸质地图与地理信息一体化生产流程,阐述了实现一体化生产必须解决一体化数据结构设计、多源数据综合利用、地图符号化机制建立、基于地理属性管理的地图编辑、地图数据质量检查、一体化地图输出等关键技术。纸质地图与地理信息一体化生产标志着数字地图制图发展进入了新阶段。  相似文献   

19.
One of the problems which continues to trouble practical applications of GIS is the time and cost of capturing data from paper maps. Even where the data are required in raster form the complexity of most maps means that the data are first digitised in vector form, and then rasterised, a slow and error-prone process. This paper describes an alternative approach based upon readily available hardware and software in which the map is scanned using Spot Colour Scanning, and then processed using a specially designed majority filter and editing with a painting package. Tests on a small scale soil map produce results which are about 80% as accurate as digitising, but take far less time to produce. An analysis of the sources of error indicates that many of these are due to the difficulty of scanning such a complex document as a map, and suggests that more sophisticated image processing algorithms may be needed to classify the original scanned image before the application of the filter algorithm.  相似文献   

20.
Open‐cast mining activity causes the largest georelief transfigurations all over the world. Large localities in north‐west Bohemia (the Czech Republic) are affected. In this area, we focus on a very significant case: the royal town Most, which has been turned into a lake. The main aim of this article is the reconstruction of the original georelief in different time periods together with analysis showing the process of landscape devastation. The workflow and analysis is based on precise elevation data obtained from aerial photographs and old maps. The georelief development is reconstructed using the digitized contour lines contained in Derived state‐map 1:5,000 (SMO5) from the years 1953, 1972, and 1980; maps of the 3rd Military Survey (year 1936); and digital surface models (DSM) extracted, using the pixel correlation method, from aerial images (year 1953 and 2008). The most important results of the analysis are digital terrain models showing the evolution of the landscape which may be used for many purposes in landscape development analysis, historical applications, visualization or landscape reclamation.  相似文献   

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