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251.
云平台下MapGIS图件在ArcGIS中还原显示技术研究   总被引:1,自引:0,他引:1  
MapGIS和ArcGIS两个GIS平台拥有不一样的符号库及渲染表达方式,这就造成在MapGIS平台下产生的图件数据要想在ArcGIS平台中还原显示较为困难。通过分析两种GIS平台下图件数据的文件格式及图面渲染方式,在Map2Shp文件转换软件和GIS二次开发技术的支持下,总结了一套半自动化完成还原显示的技术流程,在实际工作中有效地解决了文件转换过程中图面渲染内容丢失、工作量大等问题。同时在云平台虚拟环境中完成该技术流程,为同一GIS平台不同版本不兼容的问题提供了解决方案,并且缩短了图面渲染的时间,从而提高了工作效率。  相似文献   
252.
During the past century, the western hemisphere has seen a general trend of agricultural expansion on the behalf of semi-natural habitat types, such as heathlands and meadows. This has been documented in numerous studies of land use change. This trend is reflected in today’s European rural landscapes, which are dominated by intensive agriculture. However, many of these studies are based on cartographical sources, such as topographical and thematic maps, and thus prone to uncertainties regarding classification systems over time, variations in definitions of land use categories and lacking documentations of land use definitions. For this study, we conducted two change detection studies, covering the same four study areas in Denmark. The first study was based on topographic maps, and indicates a strong decline in the amount of semi-natural grassland (SNG). This was contrasted by the second study, which was based on an interpretation of aerial photos, and which indicated a much less pronounced reduction of SNGs. Year to year comparisons of these two analyses also revealed large discrepancies in the coverage of SNGs. Our results indicate that change detection studies must account for uncertainties in classifications and results should be interpreted with caution.  相似文献   
253.
根据地质勘查和矿山设计的用图需要,针对传统测图技术的滞后现状,结合矿山地理位置要素的实际情况和现代机载LIDAR技术的应用特点,经过实践创新研究,总结出符合地质勘查工作实际地图测绘的新方法、新工艺.  相似文献   
254.
ABSTRACT

We compared the ability of two legend designs on a soil-landscape map to efficiently and effectively support map reading tasks with the goal of better understanding how the design choices affect user performance. Developing such knowledge is essential to design effective interfaces for digital earth systems. One of the two legends contained an alphabetical ordering of categories, while the other used a perceptual grouping based on the Munsell color space. We tested the two legends for 4 tasks with 20 experts (in geography-related domains). We analyzed traditional usability metrics and participants’ eye movements to identify the possible reasons behind their success and failure in the experimental tasks. Surprisingly, an overwhelming majority of the participants failed to arrive at the correct responses for two of the four tasks, irrespective of the legend design. Furthermore, participants’ prior knowledge of soils and map interpretation abilities led to interesting performance differences between the two legend types. We discuss how participant background might have played a role in performance and why some tasks were particularly hard to solve despite participants’ relatively high levels of experience in map reading. Based on our observations, we caution soil cartographers to be aware of the perceptual complexity of soil-landscape maps.  相似文献   
255.
Complex perturbations in the profile and the sparsity of samples often limit the validity of rapid environmental assessment (REA) in the South China Sea (SCS). In this paper, the remote sensing data were used to estimate sound speed profile (SSP) with the self-organizing map (SOM) method in the SCS. First, the consistency of the empirical orthogonal functions was examined by using k-means clustering. The clustering results indicated that SSPs in the SCS have a similar perturbation nature, which means the inverted grid could be expanded to the entire SCS to deal with the problem of sparsity of the samples without statistical improbability. Second, a machine learning method was proposed that took advantage of the topological structure of SOM to significantly improve their accuracy. Validation revealed promising results, with a mean reconstruction error of 1.26 m/s, which is 1.16 m/s smaller than the traditional single empirical orthogonal function regression (sEOF-r) method. By violating the constraints of linear inversion, the topological structure of the SOM method showed a smaller error and better robustness in the SSP estimation. The improvements to enhance the accuracy and robustness of REA in the SCS were offered. These results suggested a potential utilization of REA in the SCS based on satellite data and provided a new approach for SSP estimation derived from sea surface data.  相似文献   
256.
陈雨诗  刘云刚 《热带地理》2022,42(7):1085-1095
运用文本分析,从中美关于南海制图的特点及差异着手,探讨了中美制图所表达的南海领域化过程以及地图对于领域化实践的作用。研究发现:1)中美制图中南海海域范围、岛礁地名及海疆边界表达的演变,是国家权力影响制图的表现。2)中美南海制图差异源于维护国家核心利益的需求:中国通过制图(再)领域化,对内加强南海海域管控,强化国民海权意识,对外宣示南海主权;美国通过制图(去)再领域化,强调南海的公海和多国属性。3)地图作为领域化工具,能够在国际舞台上讲述中国人的南海故事,也能清晰表达中国对南海诸岛和附近水域拥有主权的一贯和明确立场。应从地图维权、地图创新、地图宣传等方面加强对南海的领域化表达,使地图在南海海洋国土治理中发挥更重要的作用。  相似文献   
257.
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   
258.
In recent years, the concepts of usability, user experience, and user-centricity have gained in interest. Digital applications, developed in line with criteria related to these approaches, ask for a deeper understanding of users and their requirements. But, even though there is a wide range of methods available, the creation of user-centric applications with good usability and user experience still poses great challenges for developers. This is also true for web maps, i.e. web map applications, which today are ubiquitous on the Internet. They have evolved into an important information and communication tool and address users who do not possess any specific knowledge of Geoinformatics (GI) or Cartography. Despite the efforts made to meet the requirements and preferences of laymen, these users still often face problems when dealing with web map applications. This refers to aspects of design, content, and functionality. Here, participatory design, which is well-known in the field of Software and Web Engineering, might provide a suitable means. By engaging users directly and actively in the application development process, developers are able to gain a profound understanding of the users and their needs. However, there are several open questions regarding the use of participatory design for designing and implementing web map applications: What does the use of participatory design in web map development processes look like in detail? How and to what degree can users be involved in the development processes? Which added values exist? These questions are addressed by the project YouthMap 5020, whose main goal it was to create a prototype youth-centric web map for the Austrian city of Salzburg (zip code 5020). Applying the approach of participatory design, about 120 teenage pupils from several local schools were involved in all kinds of tasks related to the phases of generating the youth-centric Salzburg web city map. Experience and knowledge gained thereby allowed elaborating recommendations generally useful for generating youth-centric web map applications.  相似文献   
259.
《The Cartographic journal》2013,50(3):222-226
Abstract

The ETH-Bibliothek (the Library of the Swiss Federal Institute of Technology) in Zurich has employed electronic resources to vastly enhance access to its collections. This article examines how ETH has set about the task of incorporating electronic data into the map collection, and then explores how access to hard copy map materials has been revolutionized by electronic means.  相似文献   
260.
Within the history of cartography, relatively little attention has been devoted to the study of the growing body of maps and spatial data focusing on environmental issues. This is rather surprising, considering the importance of this type of cartography in the handling of the complex environmental problems of modern society. This paper analyses the development of thematic maps and spatial data focusing on the terrestrial environment of Danish landscapes. The paper is introduced with a review of the concept of environmental cartography, followed by a historical analysis of the development of environmental mapping in Denmark. Results suggest that there has been a change in the content and aim of environmental cartography in the twentieth century, from an initial focus on mapping potentials for land use improvement and optimization of the economic outputs from engagement with terrestrial ecosystems, to a focus on monitoring ecosystems and regulation of human intervention. Finally, the usefulness of the concept environmental cartography to frame analytical work dealing with the still increasing number of maps produced for environmental purposes within the history of cartography, is evaluated.  相似文献   
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