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1.
《The Cartographic journal》2013,50(1):103-105
Abstract

Why should a specialist sport require a map of its own? Trout fishing is not dependent on map use, but a carefully researched and presented map is a useful addition to the angler's tackle bag. The sport does not require the absolute planimetric accuracy of, say, an orienteering map, but careful research and selection of features is just as important. What information is essential to the angler and what is helpful? What is background information; and what, if anything, should be left off?  相似文献   

2.
Abstract

The rapid development of physically-based hydrological information and modelling systems has necessitated enhanced data entry and display systems. A 'mapping tool' is developed for the manipulation and display of spatial information, which is a cost-efficient, self-contained utility system that is suitable for use on micro-computers. It has the ability to be integrated as part of any modelling or information system. Diverse applications using the 'mapping tool' are briefly described including resource management systems for planners, mass balance studies in urban catchments and data entry systems for physically based models.  相似文献   

3.
Abstract

John Keates is very well known for his numerous scholarly contributions to cartography as an academic discipline and science. However, throughout his career, he was also very actively involved in the design and production of maps. Mostly these were specialized thematic maps produced as the result of scientific research in the field sciences, especially in geology, glaciology and vegetation studies. However, during the 1970s he was much involved in the design and production of a considerable number of maps for recreation purposes, including maps for orienteering. Many of these maps were regarded at that time as being extremely innovative in terms of their cartographic design and layout. The article outlines the development of what became known as the 'Glasgow' style of map design John Keates' involvement with recreation maps in the 1970s.  相似文献   

4.
Abstract

The Military Institution at Madras (1804–16) illustrates the centrality of surveying and mapping to late Enlightenment concepts of 'military science' and thus their centrality to the education of junior officers beyond the rudiments of military lore and drill. Pragmatically, the institution's field mapping exercises were used to provide basic topographic maps for south-east India (the Carnatic); the institution's students were also intended to serve after graduation on survey duty elsewhere in southern India. Intellectually, mapmaking was held to epitomise the 'scientific spirit' which military reformers desired to inculcate in the young ensigns: it combined mathematical and logical thought (theory) with concrete military results (practice). These last points underlie the conceptual issues of the early nineteenth-century militarisation of government cartography in Europe and the increasing 'map-mindedness' of military thinkers.  相似文献   

5.
Abstract

This paper is concerned with the future of the British national mapping agency in a society which is markedly different from that in which the Ordnance Survey Review Committee of 1979 worked. The objective is to ascertain which topographic information is needed, who should provide it, on what terms and through which mechanisms. Prior to making an attempt to answer these questions, the essential characteristics of Ordnance Survey (OS) are summarised as deduced from available documentary evidence; the changing attitudes to information as a commodity, the growing competition in British mapping and the government's stringent requirements from the Survey are also outlined as just three of the many complexities which affect OS. Building upon Smith's classic 1979 paper and subsequent experience, the rationale for government involvement in mapping is examined. It is concluded that the Survey has a continuing vital role though there are a number of steps which the OS should take in order to adapt to changing circumstances.  相似文献   

6.
Abstract

Forest cover monitoring plays an important role in the implementation of climate change mitigation policies such as Kyoto protocol and Reducing Emissions from Deforestation and Forest Degradation (REDD). In this study, we have monitored land cover using the PALSAR (Phased Array type L-band Synthetic Aperture Radar) full polarimetric data based on incoherent target decomposition. Supervised classification technique has been applied on Cloude–Pottier decomposition, Freeman–Durden three component, and Yamaguchi four component decomposition for accurate mapping of different types of land cover classes. Based on confusion matrix derived from the predicted and defined pixels, the evergreen and sparsely deciduous forests have shown high producer's accuracy by Freeman–Durden three component and Yamaguchi four component classifications. The overall accuracy of Maximum Likelihood Classification by Yamaguchi four component is 94.1% with 0.93 kappa coefficient as compared to the 90.3% with 0.88 kappa coefficient by Freeman–Durden three component and 89.7% with 0.88 kappa coefficient by Cloude–Pottier decomposition. High accuracy of classification in a forested area using full polarimetric PALSAR data may have been because of high penetration of L-band SAR. The content of this study could be useful for the forest cover mapping during cloudy days needed for proper implementation of REDD policies in Cambodia.  相似文献   

7.
《The Cartographic journal》2013,50(2):138-140
Abstract

The readjustment of a major geodetic control network results in a new set of spheroidal coordinates for the network stations. Those new coordinates followed by an appropriate control densification serve as input for computing new plane coordinates. There are many surveying and mapping products which are based on the existing 'old' plane coordinates system. This paper deals with considerations and procedures aiming at the introduction of a new projection defined in such a way as to minimise the detrimental consequences of readjustment through the use of a synthetic point of origin for the new projection.  相似文献   

8.
Abstract

This account of exploratory mapping is provided by a surveyor who started his working life as an explorer in areas where existing maps were extremely rough and rudimentary. Although the methods and results it describes will not stand comparison with modern topographical maps compiled from vertical air photographs, this frank and objective appraisal will help the 'chair-borne' cartographer to understand the importance of a thorough evaluation of some material of that type and age, which is still sometimes the best available until the new air surveys replace it.  相似文献   

9.
Abstract

Over the last three decades, the information revolution and technological advances have led to a paradigm shift in cartography. Recently, the major emphasis has been on 'democratization of cartography', where individuals can be empowered with electronic tools to analyse and visualize spatially referenced data (Morrison, 1994). But, an ordinary user can not effectively use the available GIS tools to visualize geographical data. Therefore, cartographers and/or GIS experts need to develop user-friendly map making systems to facilitate the democratization of cartography. A mapping system was designed using the advanced macro language (AML) and menus of ARC/INFO at the Curriculum for Evaluation and Management Centre (CEM) in Durham University to automate the mapping process (extending from spatial and non-spatial data extraction to the printing of a final map), so that any user can map pupils' locations of any school in the United Kingdom simply by entering some key information. The procedure followed to automate pupils' mapping is described in this paper. A similar programming approach can be helpful to automate mapping systems in a local network and on web.  相似文献   

10.
Abstract

The communication approach advocated by cartographers during the past decade appears to have provided direction but no route to improvement of the product. Much of the research in this area appears almost aimless and considerable danger is foreseen in that if a path is not quickly established and maintained the purpose of cartographic research will be lost behind ill conceived forays into 'no man's land'. The map is considered within this article as primarily a 'total product' and interdependence between its various elements seen as its strength. The current obsession with component parts detached from their operating environment appears to provide nothing of use to the manufacturer. This paper certainly is not presented as either a research or review article, but rather as a contemplative essay in which the above topics are examined and comparisons made between the cartographic and other manufacturing industries.  相似文献   

11.
ABSTRACT

This study presents an approach for generating a global land mapping dataset of the satellite measurements of CO2 total column (XCO2) using spatio-temporal geostatistics, which makes full use of the joint spatial and temporal dependencies between observations. The mapping approach considers the latitude-zonal seasonal cycles and spatio-temporal correlation structure of XCO2, and obtains global land maps of XCO2, with a spatial grid resolution of 1° latitude by 1° longitude and temporal resolution of 3 days. We evaluate the accuracy and uncertainty of the mapping dataset in the following three ways: (1) in cross-validation, the mapping approach results in a high correlation coefficient of 0.94 between the predictions and observations, (2) in comparison with ground truth provided by the Total Carbon Column Observing Network (TCCON), the predicted XCO2 time series and those from TCCON sites are in good agreement, with an overall bias of 0.01?ppm and a standard deviation of the difference of 1.22?ppm and (3) in comparison with model simulations, the spatio-temporal variability of XCO2 between the mapping dataset and simulations from the CT2013 and GEOS-Chem are generally consistent. The generated mapping XCO2 data in this study provides a new global geospatial dataset in global understanding of greenhouse gases dynamics and global warming.  相似文献   

12.
《The Cartographic journal》2013,50(3):243-253
Abstract

Indigenous people throughout the world developed their own mapping skills and systems of knowledge. While Westerners are prone to overlook these communities' geographical knowledge and imagine their mapping activities to be primitive or non-existent, their mental maps are often impressive in sophistication and detailed even if based on cosmologies that are quite foreign to Western thinking. This article depicts a mental map of the ocean floor shared by Polynesians of Anuta, a remote community in the Solomon Islands. It situates Anuta's reef map in relation to academic discussions of indigenous cartography and describes the process that resulted in the map's physical representation.  相似文献   

13.
Abstract

This new double series, commonly known under its combined title, 'Joint Operations Graphic' (JOG), is an ambitious attempt to create a new map series of world-wide coverage, suitable in its alternative forms for both ground and air operations. Conflicts of requirement between services, and between allied mapping agencies, inevitably make this an extremely difficult problem. The task is systematically analysed with regard to planning, specification, production methods and problems, and product evaluation. The accompanying printed map specimen has been provided by courtesy of Survey Production Centre. The paper was first given at the Symposium of the British Cartographic Society, Newcastle upon Tyne, September 1967.  相似文献   

14.
Geological studies in the area around Badami, Bijapur District, Karnataka, were carried out with the help of Landsat imagery and aerial photographs. The study are forms a part Kaladgi Basin which is located on the northernmost fringes of the exposed Dharwar Craton. Archaen Peninsular Gneiss and intrusive Granodiorite/Granites (≈Clospet Granite) form the basement for the Middle to Late Proterozoic Kaladgi Super Group sediments which are, in turn, overlain in the north by the Upper Cretaceous to Lower Eocene Deccan flood basalt lavas. Geological mapping of the study area and inferences about the structural setup were primarily based on interpretation of the remotely sensed data. The combined interpretative study of Landsat imagery and aerial photographs was instrumental in mapping of the lithostratigraphic units exposed in the study area along with the structures associated with them.  相似文献   

15.
ABSTRACT

The mapping of spatiotemporal point features plays an important role in geovisualization. However, such mapping suffers from low efficiency due to computational redundancy when similar symbols are used to visualize spatiotemporal point features. This paper presents a similarity-based approach to predict and avoid computational redundancy, which improves mapping efficiency. First, to identify computational redundancy, the similarity of point symbols is measured based on commonalities in symbol graphics and symbol drawing operations. Second, a similarity-enhanced method is proposed to comprehensively predict and avoid computational redundancies when mapping spatiotemporal point features. This approach was tested using two real-world spatiotemporal datasets. The results suggest that the proposed approach offers relatively large performance improvements.  相似文献   

16.
Abstract

Choosing effective colour schemes for thematic maps is surprisingly difficult. ColorBrewer is an online tool designed to take some of the guesswork out of this process by helping users select appropriate colour schemes for their specific mapping needs by considering: the number of data classes; the nature of their data (matched with sequential, diverging and qualitative schemes); and the end-use environment for the map (e.g., CRT, LCD, printed, projected, photocopied). ColorBrewer contains 'learn more' tutorials to help guide users, prompts them to test-drive colour schemes as both map and legend, and provides output in five colour specification systems.  相似文献   

17.
Abstract

Multi-sensor and multi-resolution source images consisting of optical and long-wave infrared (LWIR) images are analyzed separately and then combined for urban mapping in this study. The framework of its methodology is based on a two-level classification approach. In the first level, contributions of these two data sources in urban mapping are examined extensively by four types of classifications, i.e. spectral-based, spectral-spatial-based, joint classification, and multiple feature classification. In the second level, an objected-based approach is applied to decline the boundaries. The specificity of our proposed framework not only lies in the combination of two different images, but also the exploration of the LWIR image as one complementary spectral information for urban mapping. To verify the effectiveness of the presented classification framework and to confirm the LWIR’s complementary role in the urban mapping task, experiment results are evaluated by the grss_dfc_2014 data-set.  相似文献   

18.
19.
Abstract

The selection of a vertical scale in the production of block diagrams or three-dimensional views is a decision which can have a great effect on the map reader's perception of the information presented. Advice available in the cartographic literature is extremely subjective and refers mainly to physical data. In the absence of suitable guidelines for statistical mapping, an experimental technique is presented which utilises the power of automated cartography in determining a scale which can be applied to all types of three-dimensional surfaces.  相似文献   

20.
Abstract

Measurement of areas is necessary in many studies based on maps. Where precise measuring equipment is not available, more simple methods must be used. The information so produced can be improved in value if the degree of accuracy of the measuring technique can be stated. This paper demonstrates a 'model' by which results of the measuring technique can be judged against calculations for the same units, which are exact to one thousandth of a square centimetre.  相似文献   

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