共查询到20条相似文献,搜索用时 0 毫秒
1.
2.
《The Cartographic journal》2013,50(1):60-71
AbstractCartographic visualisations are important tools for the communication of hazard related data among stakeholders. Although these representations are essential for various hazard management tasks, an analysis of existing hazard visualisations showed that they often disregard cartographic principles. This leads to confusion on the part of users through poor representations and consequently to an impairment of the information flow. The objective of this research is to offer suggestions for enhanced hazard visualisations to facilitate hazard management tasks and decision making. Existing cartographic shortcomings are identified based on an extensive analysis of hazard visualisations and an expert survey. These shortcomings are discussed and improvements for important cartographic elements are presented. 相似文献
3.
4.
5.
6.
7.
《制图学和地理信息科学》2013,40(4):264-272
This paper reports the results of an in-depth study which investigated two algorithms for line simplification and caricatural generalization (namely, those developed by Douglas and Peucker, and Visvalingam, respectively) in the context of a wider program of research on scale-free mapping. The use of large-scale data for man-designed objects, such as roads, has led to a better understanding of the properties of these algorithms and of their value within the spectrum of scale-free mapping. The Douglas-Peucker algorithm is better at minimal simplification. The large-scale data for roads makes it apparent that Visvalingam's technique is not only capable of removing entire scale-related features, but that it does so in a manner which preserves the shape of retained features. This technique offers some prospects for the construction of scale-free databases since it offers some scope for achieving balanced generalizations of an entire map, consisting of several complex lines. The results also suggest that it may be easier to formulate concepts and strategies for automatic segmentation of in-line features using large-scale road data and Visvalingam's algorithm. In addition, the abstraction of center lines may be facilitated by the inclusion of additional filtering rules with Visvalingam's algorithm. 相似文献
8.
9.
《制图学和地理信息科学》2013,40(3):222-224
On a previously-digitized map, a series of 685 points were screen-digitized so as to represent major spatial features of each polygon composing 17 forest types having inherently uncertain boundaries; three forest types having precise boundaries were treated as such. From these points and three exact types, surfaces were generated which provided weights of the certainty of having each of the 20 forest types at a location. These surfaces were “reconstituted” into a thematic map by assigning each location to the type having the highest weight. When compared to the precisely digitized and rasterized map, areal and locational inaccuracy were 5% and 18%, respectively, for the reconstituted thematic map. For certain situations—such as the preparation of long-term forest management plans—these results show promise for adequately representing maps of natural features while reducing digitizing efforts. 相似文献
10.
11.
12.
13.
14.
15.
16.
地图目标在制图综合中的分形衰减机理研究 总被引:1,自引:0,他引:1
在分形扩展研究的基础上,结合地图综合的理论,分析了地图目标的自相似性在地图综合中的分形衰减现象,并研究了其变化原因和机理。结果表明,考虑了分形衰减现象的地图综合方法比原来认为分维数是定值的综合方法表现出了明显的优越性。 相似文献
17.
《制图学和地理信息科学》2013,40(3):161-180
Real cognitive maps encoded by humans are difficult to study using experimental methods because they are a product of complex processes whose content and timing cannot easily be known or controlled. This paper assesses the value of using neural network model simulations for investigating cognitive maps. The study simulated the learning of mapped city locations in South Carolina from reference sites in the three primary regions of the state using Kohonen self-organizing maps. The learning performances of models were considered based on available prior knowledge. Bi-dimensional regression analyses were used to assess the congruity of the simulated cognitive maps with a cartographic map and with sketch maps produced by human subjects. Error analyses indicated differences between central and peripheral reference sites. The cities known by subjects living at a central location were more evenly distributed in space and associated with significantly smaller errors. Models that learned combined state boundary and interstate highway information as prior knowledge or simultaneously with city locations consistently produced the best simulation results. The results indicated simulated cognitive maps could be used effectively to study the acquisition of spatial knowledge. 相似文献
18.
《The Cartographic journal》2013,50(3):249-267
AbstractAnalysis of eye movements has been used for decades as a method for assessing the performance of visual stimuli. Until recently, this has mainly been applied to static and non-cartographic stimuli, but due to technological developments and reduced cost of equipment, interactive and cartographic applications are now feasible. suggest a new analysis method which applies Hägerstrand’s Space-Time-Cube (STC; ) to eye movement data. However, in an interactive three-dimensional STC, identifying and exploring key behaviours can be difficult. In order to ameliorate these difficulties, we propose a variation of the STC method, which uses two-dimensional projections of the STC onto the XT and YT planes. These two-dimensional projections are found to facilitate rapid identification of significant patterns in the data set. A prototype implementing this and other dynamical methods has been developed, and is presented with examples illustrating the benefits of working with two-dimensional projections of the STC. 相似文献
19.
20.