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1.
Abstract

The Lack hitherto of studies of cycle-touring mapping in Britain is noted, and some basic attributes of cycle touring, including speed, daily distance, gradients and wind, are described. Essential and desirable qualities for a cycle-touring map are enumerated, including the need to depict all rural routes available to cyclists; it is concluded that the optimum scale is in the range 1:100 000–1:126 720, and that relief should by contours at an interval not greater than 30 metres. National mapping in the optimum scale range which were published after 1945 are then reviewed, and reasons suggested as to why none has been kept in print. The mapping available for cycle touring in Britain in 2001 is Ordnance Survey (OS) 1:50 000 Landranger series contains all the necessary information, it is too bulky to be suitable; and that most of the other maps published in the optimum scale range have inadequate relief information and all offer very limited geographical cover. The potential competition for the OS 1:50 000 from a national map series in the optimum scale range is acknowledged, and an outline specification for a 1:125 000 series is described, which seeks to minimize that competiton whilst providing all the necessary information for cycle touring.  相似文献   

2.
《The Cartographic journal》2013,50(3):179-213
Abstract

To what extent do European state topographic maps exhibit unique styles of cartography? This paper describes an investigation to classify and analyse stylistic diversity in the official 1 : 50 000 topographical mapping of 20 European countries. The method involves the construction of a typology of cartographic style, based upon the classification of distinct graphical legend symbols into mutually exclusive thematic categories. In order to identify stylistic similarities between national symbologies, hierarchical cluster analysis was performed to compare the relative proportions of symbols within each category. This was complemented by a qualitative analysis of various aspects of cartographic design: colour, 'white' space, visual hierarchy, and lettering. The results indicate a high degree of stylistic diversity throughout Europe, with the symbologies of Great Britain and Ireland demonstrating the strongest example of a supranational style. The typology of cartographic symbologies is shown to be an effective method for determining stylistic association among maps of differing geographical (and potentially historical) origins and it is suggested that the cartographic language paradigm should be revisited as a means for understanding why national differences persist in state cartography. A version of this paper was presented at the Twenty-third International Cartographic Conference in Moscow.  相似文献   

3.
Abstract

During the Second World War, the German army developed the largest organization of any nation ever to contribute military applications of earth science in wartime. In the summer of 1940, its military geologists assisted planning for potentially the greatest amphibious assault to that time in history by preparing maps which analysed the terrain of southeast England in terms of coastal geomorphology, groundwater supply, quarry sites for construction materials and off-road trafficability. These specialist maps were generated at scales of 1:50 000, 1:100 000 or 1:250 000 by annotating topographical base maps, derived from the then current Ordnance Survey maps at most similar scale, with data derived from maps and memoirs published by the Geological Survey of Great Britain or larger-scale Ordnance Survey maps. They represent an early example of geotechnical mapping skills developed more fully in the German armed forces for operations elsewhere later in the war.  相似文献   

4.
The Overseas Surveys Directorate (OSD) of the Ordnance Survey of Great Britain (OS) has experimented with using SPOT I HRV data for topographic line mapping at 1:100 000 scale in the Yemen Arab Republic (YAR). Results of these tests indicate that sufficient accuracy to support 1:100 000 scale mapping with a 40 m contour interval is possible but that the compilation of detail is incomplete. More emphasis on field completion and verification is required than with traditional techniques to maintain a standard 1:100 000 scale mapping specification. Costs of mapping large areas can be significantly reduced but savings are yet to be made in providing ground control. OSD has acquired expertise and hardware in a new mapping process, not to replace traditional mapping systems but to complement them under appropriate conditions. OSD has developed sufficient confidence in the use of SPOT to commit itself to mapping approximately 25 000 square kilometres of north east Yemen Arab Republic.  相似文献   

5.
本文在分析地形图误差的主要来源的基础上,系统地对已编印出版的1:10万、1:20万、1:50万、1:100万4种中、小比例尺地形图进行了抽样量算,提出了评定地形图精度的方法;分要素(包括经纬线网交点、河流交叉点、道路交点、居民地图形中心点)讨论了地形图的平面位置精度,在此基础上,提出了我国中、小比例尺地形图的平面位置精度标准。  相似文献   

6.
为向用户提供内容更加丰富的新型GIS产品,国家西部测图工程提出在生产1:50000线划地形图产品的同时,生产1:50000晕渲地形图产品。本文首先提出了1:50000晕渲地形图的内容及表达规则,在此基础上根据西部区域特点,分析了晕渲生成相关参数,提出西部测图工程1:50000晕渲采用斜照光源、光源方位角315°、光源高度角55°、垂直比例因子为1。其次提出了晕渲生成后的图像分辨率调整、色调调整,基本地理要素与晕渲图像叠加处理。最后提出1:50000晕渲地形图图外整饰原则。该试验的研究结果已形成生产技术文件,并应用到国家西部测图工程中。  相似文献   

7.
A short review is given of the involvement of the Institut Géographique National (IGN) in the European Space Agency Spacelab Metric Camera (MC) experiment. IGN has participated in this project from the early stages of its preparation in 1974. The assessment of MC data has been carried out for both metric and thematic purposes. Using a Matra Traster analytical plotter, a contoured map of Carpentras. included in the European standard test site of Marseille, has been prepared at a scale of 1:100 000 with 100 m and 50 m contour intervals. Preliminary comparison of this map with the topographic data base shows a height accuracy of about 30 m. Orthophotographs have been produced of the same area, at 1:100000 scale and at 1:250000 scale. showing good agreement with the basic line map. An infrared colour pseudo-orthophotograph has been produced for Khartoum (assuming that the ground was flat) and a space map of a desert area of Algeria has been printed at 1:200000 scale, allowing a good comparison with the drainage shown on the existing line map. Interpretation of the MC photography has also been assessed and compared with conventional IGN aerial photography taken over the European standard test site. Due to the low sun elevation and the apparent image motion which affected the MC photography, the result is not as good as was expected. Some linear features of 6m width are visible (for example, roads and hedges) but for positive identification a width of 18m is necessary. It is difficult to determine the extent of cities and land parcels less than 40 × 40m are not visible. However, the MC data can be used for checking and revising some features of small scale maps (smaller than 1:100000). Two experiments have been performed in thematic interpretation, one concerned with land use and the other with forest mapping. Some improvements of the MC are suggested in order to satisfy the major requirements of users while the possibilities of topographic mapping from these data are summarised.  相似文献   

8.
北京市大比例尺地形图图幅号查询信息系统的研制   总被引:2,自引:0,他引:2  
供应大比例尺地形图是城市测绘资料管理部门的基本职能。文中论述了在ARC/INFO基础上,以1:25000比例尺地形图上的点、线、面地物为索引,查询北京市1:500~1:10000各类比例尺地形图图幅号的算法。实验表明系统是实用的。  相似文献   

9.
Abstract

Image mapping using data from visible and infrared sensors has, as a major drawback, the frequent cloud cover experienced in many countries. This is one of the main reasons why topographic maps at 1:100,000 scale and larger are often outdated. The results of a study which investigated the possibilities of fusing up‐to‐date spaceborne microwave data with existing images from optical sensors for topographic map updating at a scale of 1:100, 000 are presented in this paper. A key issue researched was the influence of geometric distortions and corrections of remote sensing data on the results of pixel based digital image fusion. After having terrain‐geocoded and radiometrically enhanced imagery from the Landsat, SPOT, ERS‐1 and JERS‐1 satellites, the data were fused applying a variety of colour transformation techniques as well as statistical or arithmetic methods. Initially, the image fusion was implemented using images covering a test site in the north of The Netherlands in order to calibrate specified combinations and techniques in a rather flat area. With the experience gained, the remote sensing data acquired over the research site were processed. The research test site is located in a typical Developing Country in the humid Tropics, on the mountainous south‐west coast of Sumatra in Indonesia. The results of the various applied techniques and image combinations were evaluated with reference to their capability to overcome the cloud cover problem. New combinations of techniques and images were developed as result of an optimisation process. The research produced two prototypes of annotated 1:100,000 scale image maps containing fused, cloud‐free optical/microwave imagery.  相似文献   

10.
The Ordnance Survey of Great Britain (OS) is a Principal Investigator for the Metric Camera experiment being organised by the European Space Agency (ESA). Two investigations are being conducted by the OS, both concerned with the potential value of the photography for topographic mapping and map revision. The first relates to Great Britain and the second relates to the developing countries of the world. Neither of these investigations is complete and only interim results and conclusions can be presented.  相似文献   

11.
在调查研究和对我国国家基本地形图及其相应编绘规范和图式的分析研究基础上,参照国外许多地形图的设计,提出改进我国国家基本地形图设计的几个方面:改进国家基本地形图的比例尺系列及分档;地形图的设计文件需进一步标准化、规范化和系列化;国家基本地形图应适应时代发展的需要;改变我国地形图的旧面貌  相似文献   

12.
Abstract

This paper describes the design and development of two trial 1:100 000 scale Ordnance Survey maps targeted specifically at the inexperienced and reluctant map users in the touring and holiday market. These are two maps which depart from the very high map specification designs normally offered by Ordnance Survey. The use of extensive consumer market research and the objective analysis of existing touring type maps on sale have enabled Ordnance Survey to publish two experimental maps, which will succeed or fail by consumer reaction alone.  相似文献   

13.
《The Cartographic journal》2013,50(4):329-341
Abstract

The background and context to the cartography of the French military engineer Lewis Petit and his work in Scotland is explained. Petit was responsible for drafting the earliest plans and profiles of four castles in the north-west Highlands of Scotland (1714), as well as the earliest town plans of Perth and Inverness (1716). A consideration of their functions, particularly through the Board of Ordnance archives, allows a better understanding of these plans and their value as historical sources, as well as their accurate dating. Petit's work reflected national and international developments, including war in Europe and the Jacobite rebellions in Britain. His cartography illustrates the spread of new European military theories and practices, at a time when a professional corps of military engineers was being established in Great Britain. Through studying Petit and his maps we can gain a fuller understanding not only of the Board of Ordnance in Hanoverian Scotland, but also of the militarisation of cartography in the eighteenth century, and the emergence of standards relating to colour, scale and terminology.  相似文献   

14.
During 1994 a project was initiated by Ordnance Survey to investigate the requirement for completing the multi-million pound digital revision of 1:2500 scale mapping within Great Britain. This paper, although concentrating on this scale of mapping, discusses the revision policy issues that faced Ordnance Survey and the practical implications arising from implementing the policy for its 1:2500 and 1:10 000 basic scale mapping. Use of contractors was seen as a prime requirement as the resources available within Ordnance Survey were not sufficient to implement the full revision programme. This paper discusses the background to the task and considers the range of photogrammetric options and contractual and quality procedures required for the revision of the mapping over the next few years.  相似文献   

15.
省级测绘档案资料馆馆藏了该省内各市、县的1∶500,1∶1 000等大比例尺地形图数据,这些数据大多采用地方坐标系。由于城市大比例尺数据的空间参考多为地方坐标系,使得对大比例尺数据进行统一查询、统计、定位难以实现。本文提出由地方坐标系地形图数据的图幅号生成相应的结合表,并将其转换到国家坐标系,将国家坐标系下的大比例尺结合表叠加到国家基本比例尺地形图数据中,可快速查询、定位到需要的城市大比例尺数据。  相似文献   

16.
The French topographic database is a three dimensional database whose content is very near to that of the IGN 1:25 000 scale maps. It has a metric accuracy and is designed to have three aims (maps at scales of 1:25 000 and 1:50 000 and the topographic part of the cadastral map at 1:5000 scale, providing located structured data). The structure, including topology information, is described. The process of data capture is based on photogrammetry and field completion. Experiments concerned with revision are being made in order to define the methodology precisely.  相似文献   

17.
《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   

18.
《The Cartographic journal》2013,50(2):111-136
Abstract

During the German occupation of the Channel Islands, military geologists produced specialist maps to support their development as part of the Atlantic Wall: the line of fortifications marking the western boundary of German-occupied Europe. For Jersey, maps showed features of groundwater and quarry sites for building materials, primarily at a scale of 1 : 25 000. For Guernsey, maps at this scale were prepared to depict bedrock and superficial geology, and also maps which showed sites for building materials, water supply and features of military geology. For Alderney, maps at 1 : 10 000 showed bedrock geology, water supply, building materials plus tunnelling conditions, and military geology. Only a few contemporary copies of these maps were produced, hand-drawn upon printed topographical base-maps. Some are now preserved in Germany at the Bundesarchiv-Militärarchiv, others in the USA at the National Archives and Records Administration. They include the only military geology maps, the earliest large-scale groundwater maps and arguably the earliest large-scale building resources maps, for any part of the British Isles.  相似文献   

19.
针对社会公众对国家空间地理信息资源,特别是国家基本比例尺地形图的开放使用与保密问题中的一些模糊认识,从知识产权属性、地形图的生产原理以及在空间地理信息资源共享中应用互联网技术应注意的问题等几个方面予以廓清,并介绍了国家有关方面在国家空间地理信息资源的开放使用与保密管理方面的研究思路。  相似文献   

20.
伍素贞  方子岩  莫志恒 《东北测绘》2012,(3):187-189,193
当对一个较大测区用全站仪或摄影测量方法测绘某种比例尺地形图时,可获得数量较多的地形图。对获取的数字地形图进行精度评定,是质量检查中的一个重要环节,而且工作量较大。AutoCAD为平台开发的测图软件在测绘行业十分流行,测绘行业生产的数字地图一般都能转化为DWG格式。对于DWG格式的地形图,在AutoCAD打开的图上拾取若干地物点,并把这些点的坐标自动形成一个坐标文件,与外业测量仪器RTK采集相应点形成的坐标文件,通过精度评定程序进行同名点号的坐标值对比,获得数字地形图数学精度,大大提高了数字地图精度检测工作的效率。  相似文献   

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