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11.
Cognitive map-design research has the goal of understanding human cognition in order to improve the design and use of maps. As a systematic sub-discipline of cartography, cognitive map-design research is a phenomenon of the twentieth century, specifically the latter half. Robinson's The Look of Maps, published in 1952, played a seminal role in the genesis of cognitive map-design research in several countries, but it had interesting precursors. Empirical work that followed from The Look of Maps included psychophysical studies of graduated circles and studies of eye movements during map reading. Theoretical work that followed included a variety of cognitive theories but especially the development of the communication model as a comprehensive framework foi˙ scientific cartography. I chart the changing fortunes of cognitive map-design research after The Look of Maps and offer explanations for these changes. I also consider the legacy of cognitive map-design research—ways in which it has or has not mattered. I conclude with a list of questions suggested, but not decisively answered, by this exploratory essay.  相似文献   
12.
Areal gray tone symbols produced on standard line printers seldom adhere to acceptable cartographic design standards. The recent development of matrix line printers provides an alternative means of producing more effective map symbolization with a device also suitable for ordinary character output. Matrix printers permit a greater range of gray tones in a regular sequence, more uniform symbol configuration, and improved print quality  相似文献   
13.
Introduction     
We introduce and test an algorithm for extracting high-point locations from statistical surface data. The algorithm uses map algebra and local neighborhood analysis via three key parameters: minimum vertical gain, vertical gain neighborhood, and horizontal separation neighborhood. Though the method is applicable to any x,y,z data set, we tested it on 1:250,000 digital elevation models (DEMs) for Arizona. The resulting high points were compared quantitatively with an independent data set of named summits from the USGS Geographic Names Information System (GNIS). The comparison showed that, on an aggregate basis, the extraction method can approximate the number and spatial pattern of high points when compared to the GNIS points. However, extraction by neighborhood analysis may consistently misdiagnose certain features, such as the edges of troughs (e.g., canyon rims).  相似文献   
14.
Tactual maps can be useful aids for blind mobility. Sighted visitors to an exhibit on maps for the blind at the August 1972 International Geographical Congress had an opportunity to try out tactual mobility maps for themselves. Blindfolded participants attempted to guide themselves through a maze with the help of such a map. Over half of those observed had some difficulty in finding their way. Evaluation of their performances suggests that unfamiliarity with methods for reading and using tactual maps was a major problem. The maze and tactual map exhibit also emphasized that tactual maps differ from visual maps in content, design, and reproduction. Special requirements in all these areas will have to be met before tactual mapping can fulfill its promise as a mobility tool for the blind.  相似文献   
15.
A hybrid system that integrates two-dimensional (2D) GIS and three-dimensional (3D) visualization has been developed to provide unique solutions to application domains where traditional 2D GIS and 3D visualization cannot alone provide a solution. In this paper, we focus on three key issues in realizing such an integrated system, including large-scale terrain rendering, 2D and 3D combination display (for example, rendering 2D GIS layers in 3D space), expanding traditional 2D GIS analysis functions into a 3D environment, and visualizing 3D geographical data. A generic framework is developed to integrate 3D visualization with various types of 2D GIS, such as commercial GIS software, open source GIS software and spatial databases. A prototype 2D and 3D hybrid system that seamlessly integrates 2D GIS (developed with ArcEngine) and 3D rendering engine (developed with DirectX) is then developed based on the framework. In this hybrid system, 2D and 3D data are viewed within the same scene. Multiple 2D GIS layers are overlaid on the base terrain using a Level of Detail (LOD) model. Advanced query functions, data accessing, data management and spatial analysis, which are executed in the traditional 2D GIS, are provided to users in a 3D environment by continuously transforming information between the 2D GIS subsystem and the 3D subsystem. The 3D data are organized and displayed by Keyhole Markup Language (KML) and textured 3D models in the COLLAborative Design Activity (COLLADA) format. The prototype demonstrates that this hybrid system has effectively addressed the three key issues identified above and that it can seamlessly integrate 2D GIS and 3D visualization. The hybrid system has great potential to be employed in many application domains, such as urban planning, landscape design and environmental decision making, among others, to enhance the 3D design capability and facilitate public participation in the planning, design and decision-making process.  相似文献   
16.
The Lophius vomerinus component of the monkfish resource off Namibia was assessed by means of deterministic length- and age-based models. Steady state length cohort analyses illustrated that, although the model was sensitive to the rate of natural mortality, it was relatively insensitive to changes in terminal fishing mortality. These biases may, however, not be serious provided that estimates of abundance are used to reflect relative changes in the biomass dynamics of the population. The age-structured production model, tuned to trends in General-Linear-Modelling-standardized catch-per-unit-effort data and relative abundance indices calculated from hake (Merluccius spp.) biomass surveys, together with observed commercial and survey catches-at-age, showed similar trends. Both models provided evidence that the monkfish resource was fully to overexploited, with current harvesting levels higher than those concomitant with sustainable yields.  相似文献   
17.
Users of geographic information systems (GIS) usually render terrain using a point light source defined by an illumination vector. A terrain shaded from a single point provides good perceptual cues to surface orientation. This type of hill shading, however, does not include any visual cues to the relative height of surface elements. We propose shading the terrain under uniform diffuse illumination, where light arrives equally from all directions of a theoretical sky surrounding the terrain. Surface elements at lower elevations tend to have more of the sky obscured from view and are thus shaded darker. This tinting approach has the advantage that it provides more detailed renderings than point source illumination. We describe two techniques of computing terrain shading under uniform diffuse illumination. One technique uses a GIS–based hill-shading and shadowing tool to combine many point source renderings into one approximating the terrain under uniform diffuse illumination. The second technique uses a C++ computer algorithm for computing the inclination to the horizon in all azimuth directions at all points of the terrain. These virtual horizons are used to map sky brightness to the rendering of the terrain. To evaluate our techniques, we use two Digital Elevation Models (DEMs)—of the Schell Creek Range of eastern Nevada and a portion of downtown Houston, Texas, developed from Light Detection and Ranging (lidar) data. Renderings based on the uniform diffuse illumination model show more detailed changes in shading than renderings based on a point source illumination model.  相似文献   
18.
Creative, productive human activity is often associated with a melding of rational-analytical thinking and intuitive-holistic thought. In this paper the common sense basis of map design and production is related to the integration of these two distinct but complementary ways of processing information. A variety of internal (physiological/psychological) and external (data, materials, tools, working conditions, map audience) circumstances that influence cartographic education are viewed within the framework of these two cognitive styles. This balanced approach to cartographic education is less frustrating and potentially more effective for students than much contemporary course work with its strong rational-analytical emphasis.  相似文献   
19.
This paper describes two mapping algorithms for plotting the templates needed to construct three dimensional landform relief models. A contour relief model and a profile relief model were assembled using the elevation data extracted from Defense Mapping Agency 1:250,000 scale Digital Terrain Tapes.  相似文献   
20.
The analysis of dynamic spatial systems requires an explicit spatio-temporal data model and spatio-temporal analysis tools. Event-based models have been developed to analyze discrete change in continuous and feature-based spatial data. In this paper, a spatio-temporal graph model is described that supports the analysis of continuous change in feature-based polygon spatial data. The spatio-temporal graph edges, called temporal links, track changes in polygon topology through space and time. The model also introduces the concept of a spatial-interaction region that extends a model's focus beyond short-term local events to encompass long-term regional events. The structure of the spatio-temporal graph is used to classify these events into five types of local polygon events and two types of spatial-interaction region events. To illustrate its utility, the model is applied to the ecological question of how patch size influences longevity in underwater plant communities in Chesapeake Bay, USA. Both a short-term local analysis and a longer-term regional analysis showed that patches of plants, or groups of patches, larger than one to two hectares in size were more likely to persist than smaller patches or groups of patches. Overall, the spatio-temporal graph model approach appears applicable to a variety of spatio-temporal questions.  相似文献   
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