导航电子地图增量式更新服务模式

为了解决导航电子地图数据生产成本高昂、更新周期长等问题,提出了由导航变化数据发现、分析、采集、制作、发布构成的导航电子地图增量式更新闭环服务模式,将公众和导航数据用户等非专业数据生产人员纳入到导航电子地图数据维护和更新框架,可以提高数据的现势性,而且大大地降低生产和应用成本,为导航电子地图服务提供了一种可操作性强的参考模式。     

清单式管理在地震应急技术保障中的应用研究

地震是一种突发性强和破坏性大的自然灾害,重特大地震的发生往往致使较重的人员伤亡和财产损失。科学制作并合理利用应急技术产品是提升抢险救援效率的有效措施,可以有力支撑指挥层级快速决策与应急指挥。以四川长宁"6·17"地震中的应急技术保障工作为参鉴,结合当前常用应急监测技术手段,全面梳理应急技术保障产品在实践应用中的常态问题。并在此基础上,引入"清单制"管理思维,从何种阶段制作哪类产品,哪类产品需要哪些要素上进行细化构思,建立地震灾害应急技术保障产品清单,从管理模式上规范技术保障机制,促使地震应急技术支撑有力并且有序,切实提升震后应急处置效率。     

iPad电子地图(集)制作方法研究

随着智能移动终端的极大流行,通过将传统的纸质地图(集)制作成智能移动终端(如iPad)上的电子地图(集),能够更灵活地提供地图服务。本文主要探讨iPad中可阅读的两种格式(ePub与PDF)的电子地图(集),介绍了其制作技术路线和方法,以及iPad电子地图(集)典型的导入方法。     

Education

The goal of this article is to analyse several aspects of the construction of a unique project in cartography: the three-dimensional model of the city of Cadiz constructed between 1777 and 1779. Cadiz was the most important fortification in Spain at the time. We focus on new investigations of the two documentary sources relating to the construction of this maquette, or relief map, which hitherto have not been studied in conjunction. This approach facilitates an elucidation of the details of the production of the relief map that benefits from improved knowledge regarding materials, tools, construction techniques and the cost of preparing the model. Additionally, new conclusions are drawn regarding the true utility of maquettes at court and the possible causes of the sudden cancellation of this military project.     

The British Cartographic Society Awards 2006

Abstract

While graphic variables in 2D maps have been extensively investigated, 4D cartography is still a widely unexplored field. In this paper, we investigate the usefulness of 4D maps (three spatial dimensions plus time) for cartographically illustrating spatio-temporal environmental phenomena. The presented approach focuses mostly on explorative research rather than on enhancement and extension of existing methods and principles. The user study described in the paper shows that 4D cartography is not a well-explored research area and that many experienced map users try to apply their knowledge from 2D maps to 4D dynamic visualisations. Thus, in order to foster the discussion within the community, we formulated several basic research questions for the area of 4D cartography, which range from methods for representing time in 4D visualisations and understanding the temporal context to finding generic methods to achieve optimized temporal generalisation and a consistent definition of graphical variables for 3D and 4D.     

Maps > Representation

Abstract

Colour is considered a key means of expression for use in cartographic works. This is because colours and the relations among them influence not only the aesthetic impression a map creates but also its overall utility. In addition to Newton’s spectral colour theory, today theories with origins in artistic technique are gaining ground in cartography. This article introduces J. Itten’s colour theory (first published in 1961 in The Art of Colour [Kunst der Farbe]) with special attention given to his concept of seven colour contrasts. The article also discusses the suitability and unsuitability of their application in practical cartography, and it contributes original examples employing thematic maps, a discipline with broad possibilities for the application of these inventive methods by today’s mapmakers.     

Towards a Deeper Understanding of Cartographic Text Visualisation: Assessment of User Preferences and Colour Influence

The main goal of this research is to investigate the influence of a map’s background colour on user preferences regarding labels’ typography, including their size, shape, orientation and texture. Four sets of backgrounds were tested: blank maps, grey scale, hot colours and cold colours. The foreground of these maps is populated with name labels, which are associated with point objects or areal objects. Bertin’s visual variables were applied to this set of name labels, both separately and in combination. User preferences of different typographic variations were registered and compared on the basis of different background colours using a one-way ANOVA. The results indicated that the typographic design of the map labels should not be adapted according to the map’s background colour.     

Maps as Knowledge Aggregators: from Renaissance Italy Fra Mauro to Web Search Engines

Abstract

For many years geological students have been graduating from universities with little knowledge of how to use the cartographic language of line, letter, symbol and tone by which the distribution and spatial arrangement of earth science data can be best expressed. The author discusses the development of the teaching of geological cartography in the Department of Earth Sciences at the University of Leeds. Details of this innovation are set against the background of data obtained from a recent questionnaire on the practice of cartography as a discipline in departments of geology in British universities.     

Generating and mapping population density surfaces within a geographical information system

Abstract

The spatially discontinuous choropleth map is a poor representation of the underlying continuous distribution of population density. A possible alternative is to derive dasymetric maps at a fine spatial resolution by making use of satellite imagery in a geographical information system. However, there are cartographic problems when these maps are displayed and further processing is needed in order to obtain approximations to a continuous density surface. Isarithmic maps of these density surfaces retain a high degree of spatial accuracy while providing pleasing and highly adaptable presentations.

The methods used to generate dasymetric and isarithmic maps are readily implemented in most raster based geographical information systems. For example, the classification of remotely sensed imagery, the subsequent processing and integration of data, and most of the cartographic display, were all undertaken in this work using the low cost IDRISI GIS that operates on standard IBM PC compatible hardware.     

网络RTK放宽收敛阈值对点位精度影响的探讨

网络RTK测量过程中,参数设置直接影响到观测点位的精度,因此技术规范均严格要求了相关限差范围。本文就如果仅平面与垂直收敛阈值均超出限差1cm范围,将对点位精度产生多大的影响进行探讨。