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1.
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   

2.
The graticule of meridians and parallels is a largely artificial type of map boundary that can detract from the display of irregular features such as oceans. Such natural boundaries as shorelines may be used instead as the boundary of world maps. The principle of natural boundaries has been applied to several examples of equal-area or conformal world ocean maps with single or multiple lobes. By careful selection of the poles and centers, these maps can show both oceans and continents in their entirety on a single map.  相似文献   

3.
This paper presents a model which combines three of the parameters of the "Swiss manner" of relief representation with the Yoeli method of analytical hill-shading.

The model consists of various computational and graphic procedures that are intended to imitate by computer the complex hand-shading process. The first two procedures adjust the light source vertically and horizontally to the local relief forms. The adjustments avoid the disappearance of edges in unfavorable positions and exaggeration of others, and they utilize digitized data of the network of ridges and ravines. A third algorithm deals with "atmospheric perspective," the phenomenon of diminished value contrast in low lands and enhanced contrast in upper areas. This procedure also allows a general change in tonal value as a function of altitude. Other procedures deal with multicolor relief shading techniques, small-scale generalization, and selected reproduction problems.

Graphic output has been performed on a modified printer (IBM 1443) and a CRT raster recorder.  相似文献   

4.
Cartographers have long discouraged the use of spectral, or rainbow, color schemes on thematic maps of quantitative geographic data, though such color use is common in GIS and scientific visualization. Recent research, however, has shown that spectral schemes are preferred and are interpreted accurately when used as multi-hue renditions of diverging schemes. Both spectral and diverging schemes can emphasize a critical point within a data range with light colors and emphasize both high and low extremes of the data with dark colors. Although spectral schemes include multiple saturated hues, they can be designed to accommodate map reading by people with red-green impaired color vision by skipping over the yellow-greens in the spectral sequence. Cartographers should encourage use of spectral color schemes for depicting diverging quantitative data, rather than insisting that these schemes should not be used.  相似文献   

5.
A technique used for well over a decade by the U.S. Geological Survey to prepare maps for scanning and printing can be adapted for other uses as well, resulting in excellent-quality single display copies and facilitating color-scheme experimentation for maps. Materials needed for and steps in the process are detailed here.  相似文献   

6.
This paper presents concepts that motivate the use of hexagon mosaic maps and hexagon-based ray-glyph maps. The phrase "hexagon mosaic map" refers to maps that use hexagons to tessellate major areas of a map, such as land masses. Hexagon mosaic maps are similar to color-contour (isarithm) maps and show broad regional patterns. The ray glyph, an oriented line segment with a dot at the base, provides a convenient symbol for representing information within a hexagon cell. Ray angle encodes the local estimate for the hexagon. A simple extension adds upper- and lower-confidence bounds as a shaded arc bounded by two rays. Another extension, the bivariate ray glyph, provides a continuous representation for showing the local correlation of two variables. The theme of integrating statistical analysis and cartographic methods appears throughout this paper. Example maps show statistical summaries of acidic deposition data for the eastern United States. These maps provide useful templates for a wide range of statistical summarization and exploration tasks. Correspondingly, the concepts in this paper address the incorporation of statistical information, visual appeal, representational accuracy, and map interpretation.  相似文献   

7.
The quality of dynamic map symbols plays an important role in the representation of spatial-temporal changes. This paper reports an investigation into the quality of dynamic symbols. To assess the quality of such symbols, a set of traffic flow data is used for the production of different kinds of dynamic maps, with focus on four variables, i.e. size, color, frame rate and display format. Two quantitative measures are used for analysis, i.e. deviation and response time. A set of traffic data is used for the production of dynamic maps for evaluation. The experimental results show that the size is more efficient and more effective than color for dynamic maps with the same frame rate and display format. The most efficient and effective color class number is 10 on the large format display such as 1024 × 768 pixels. And the most efficient and effective size class number is 15 on large format display such as 1024 × 768 pixels. The effective frame rate for dynamic map animation is smaller than that of the general animation on the Internet or Quick Time and AVI format video. The most efficient and most effective frame rate is 3 frames per second in the color expression and 6 frames per second in the size expression. In sum, the effective and efficient value of color, size and frame rate on large format display is less than the value on the small format display. These results suggest the frame rate should be reduced on the small format display. It is hoped that the results from this study will be of help in the design of effective and efficient dynamic map symbols for geographical information visualization.  相似文献   

8.
Opponent Process theory is a model of human color perception that predicts that there are four unique hues, with all others appearing as mixtures. An experiment was conducted to evaluate this model for its ability to predict the perception of qualitative relationships in single-variable quantitative series. Two such series were tested—“Balance” schemes where the categories represent varying mixtures of two distinctly different phenomena, and “Bipolar” schemes where the series divides into halves of differing interpretation. The results indicate that Balance schemes were most often associated with part-spectral hue progressions that fell between unique hues, while Bipolar schemes were associated with hue progressions that crossed a unique hue. This effect however is apparent only when value relationships are “double-ended” within the series.  相似文献   

9.
《The Cartographic journal》2013,50(2):104-114
Abstract

This paper presents a technique for creating oblique view maps of urban areas. We identify and apply cartographic and cognitive principles to develop a solution in the context of state-of-art geographic information systems. The gap in the ability of these systems to render three-dimensional buildings into maps is addressed. At the core of our solution is a building facade modelling approach that supports varying degrees of abstraction. This is achieved by introducing a concept of 'facade waveforms' and representing building facades as combinations of these waveforms. A Fourier series approximation of the waveforms is used during the rendering processes resulting in an elegant solution to anti-aliasing. The formulation retains the semantic information in the representation that enables meaningful extensions like night time facade generation. The solution is implemented as a pixel shader and therefore leads to a large reduction in texture memory requirement compared with existing building rendering techniques. Additionally, in the case of web based systems, there is significant reduction in bandwidth requirement. We highlight the features of the proposed solution by generating demonstrative maps and images.  相似文献   

10.
ColorBrewer in Print: A Catalog of Color Schemes for Maps   总被引:1,自引:0,他引:1  
ColorBrewer is a tool that assists mapmakers in choosing and creating color schemes. It is available online at <www.ColorBrewer.org>. The color schemes range from 3 to 12 classes and are organized into three basic categories: sequential, diverging, and qualitative. Each of these scheme types has general perceptual characteristics which are described using Munsell hue, value, and chroma specifications. Each scheme has been proofed from color-separated negatives and adjusted to offer CMYK (cyan, magenta, yellow, and black) specifications that produce a readable map when they are used in process-printed publications. This paper offers a printed catalog of all of the ColorBrewer schemes to allow mapmakers to evaluate the appearance of each scheme before they commit to using them in print publications. Since process-color proofing is expensive, this catalog will reduce mapmakers' costs and allow them to be more confident that their maps will make the transition from the desktop computing environment to publication without compromising the intended message through poor color specification.  相似文献   

11.
Efforts within cartography on indoor maps have previously not received a lot of attention. Work that has been carried out on indoor maps often focus on map design very similar to an architectural style (Klippel et al. 2006; Ciavarella and Paternò 2004). In some cases the design has been of a more novel character where approaches with augmented and virtual realities have been carried out (Radoczky 2007; Müller et al. 2006). Common to these approaches is the depiction of one floor per map. As well, the primary user task is often solely personal navigation. In this article I present an innovative approach to indoor maps. The design is directly inspired by underground tube maps first developed by Harry Beck (Garland 1994) and today a common design for public transport maps. The main advantages of the map design are its simplicity and the possibility of including all floors in one map view. This allows the map user to easier comprehend the structure of the building without using several maps, as commonly needed with today's indoor map designs. I present several different map styles each intended to satisfy different user groups and tasks depending on the user's familiarity with the environment. In addition the article motivate for new application areas suitable for indoor maps, especially large hospitals. I hypothesize that the design proposed in this article leans very well to displaying real-time dynamic geospatial information, such as patients, staff, equipment and room availability within hospitals. Due to the early phase of the work presented here I outline the needed further work and possibilities of technological platforms as well as evaluations necessary in order for the design to gain acceptance and success.  相似文献   

12.
Animated choropleth maps enable cartographers to visualize time-series data in a way that congruently depicts change over time. However, users have difficulty apprehending information encoded within these displays, and often fail to detect important changes between adjacent scenes. Failures of visual experience, such as change blindness, threaten the effectiveness of dynamic geovisual displays, in which several important changes can occur simultaneously throughout the display. Animated choropleth maps require viewers not only to notice changes but also understand symbolic meanings encoded in rapid transitions between scenes. Graphic interpolation between key frames, also known as “in-betweening” or “tweening”, smoothes transitions and lengthens the duration of the transition between scenes in a dynamic sequence. Previous cartographic literature suggests tweening could be a potential solution for change blindness in the cartographic context. This article examines this issue of change blindness in the cartographic context and reports on a human subjects investigation designed to evaluate the influence of cartographic design variables on map readers' change detection abilities. Our results indicate that 1) map readers have difficulty detecting changes in animated choropleth maps, 2) map readers over-estimate their own change detection abilities, and 3) tweening influences the legibility of change in animated choropleth maps.  相似文献   

13.
根据某地区的分区统计数据和有关图集,总结设计出4种方案的分区统计地图,在自行编制的认知测试软件上进行了目标搜寻测试。结果表明,在分区统计地图上搜寻目标时,视觉系统运用了平行加工策略和序列加工策略,4个方案的目标搜寻平均反应时间和正确率受到这两种策略的影响。  相似文献   

14.
Abstract

Some, but not all, branches of the tourist industry make heavy use of maps. The industry has discovered the marketing potential of the Internet but in many cases has not yet fully exploited the extra potential of web maps compared to the traditional paper maps. Web maps can up-to-date tourist information very well but they have to be carefully designed to take account of the limitations of the medium. To be most effective, web maps should be basically simple and convey sufficient information interactively, on request. The map and symbol design should convey intuitively where and how this interaction can take place. This paper summarizes the typical faults found in tourist web map design and provides suggestions on good design practice.  相似文献   

15.
In order to create a useful map, the cartographer must select a scale at which the map reader can distinguish features shown on the map and read their labels. However, the choice of scale for a paper map is also constrained by the size of the map sheet and by the cost of working with a large number of sheets. When the feature density pattern allows, space can be conserved by making the map at more than one scale: a small scale suitable for most of the map, while dense features are shown on inset maps at larger scales. Creating inset maps requires the cartographer to make a series of complex, interrelated decisions regarding the most effective overall sheet configuration, which is dependent upon the scale chosen for the main map and how the inset maps are created. The Census Automated Map Production System (CAMPS) applies cartographic logic and density analysis to make these decisions in a fully automated mapping environment.  相似文献   

16.
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   

17.
Predictions of the 1960s about the computer's potential to change cartography are finally being fulfilled. Dynamic maps for vehicle navigation, interactive cartographic/statistical tools, and map animation are being investigated actively. As these new environments for mapping become available, we must reevaluate past questions about transformations from reality to data and data to map. In this paper, we consider these transformation questions in the context of statistical map animation. The issues discussed were raised in producing a “map movie” depicting the spread of acquired immune deficiency syndrome (AIDS) over time. Jenks' data model concept is used as the basis for a typology of data models representing phenomena typically depicted by enumeration unit data. The typology is then used to evaluate symbolization decisions for AIDS incidence maps. Implications for symbol selection imposed by dynamic rather than static maps are considered, as are technical issues involved in producing the animation on a microcomputer platform. A hybrid symbolization method that we have termed the “chorodot” is suggested as a way to meet the constraints on symbolization imposed by animation and to represent the appropriate data model for AIDS incidence.  相似文献   

18.
Researchers have long debated the mental representation of knowledge. The theories initially spawned by this debate were propositional theoty, imagery theory, and dual-coding theory. Related research further suggests that knowledge encoding processes such as landmark-based and path-based learning may also affect these representations. Such theories form a basis from which cartographers can begin to explore the mental representations of spatial knowledge. The purpose of this study was to assess the mental organization of spatial information and to examine the effect of varying the encoding process. An experiment was conducted in which subjects studied a map presented to them using one of three encoding processes and one of two grid conditions. Subjects then examined a series of test maps and determined whether each map was the same as or different from the original studied map. Test maps that differed from the original map studied were modified by either replacing, displacing, or reversing the perspective of a map object. Results of the study indicated that the type of encoding process, type of map modification, and type of spatial object manipulated all significantly affected the accuracy with which subjects completed the tasks.  相似文献   

19.
Depending on scale, topographic maps depicting the shape of the land surfaces of the Earth are produced from different data sources. National topographic maps at a scale of 1:25 000 (25K maps) produced by General Command of Mapping are used as the base map set in Turkey. This map set, which consists of approximately 5500 sheets, covers the whole country and is produced using photogrammetric methods. Digital Elevation Models (DEMs) created from these maps are also available. Recently, another data source, Synthetic Aperture Radar (SAR) interferometric data, has become more important than those produced by conventional methods. The Shuttle Radar Topography Mission (SRTM) contains elevation data with 3 arc-second resolution and 16 m absolute height error (90 percent confidence level). These data are freely available via the Internet for approximately 80 percent of the Earth's land mass. In this study, SRTM DEM was compared with DEM derived from 25K topographic maps for different parts of Turkey. The study areas, each covering four neighboring 25K maps, and having an area of approximately 600 km2, were chosen to represent various terrain characteristics. For the comparison, DEMs created from the 25K maps were obtained and organized as files for each map sheet in vector format, containing the digitized contour lines. From these data, DEMs in the resolution of 3 arc-second were created (25K-DEM), in the same structure as the SRTM DEM, allowing the 25K-DEMs and the SRTM DEM to be compared directly. The results show that the agreement of SRTM DEM to the 25K-DEM is within about 13 m, which is less than the SRTM's targeted error of 16 m. The spatial distribution of the height differences between SRTM-DEM and the 25K-DEM and correlation analysis show that the differences were mainly related to the topography of the test areas. In some areas, local height shifts were determined.  相似文献   

20.
Understanding the spatial dimension of fear of crime in the urban environment is important to understanding behaviors in response to this concern. Making this connection between perception and action has long been a goal of scholars in the social and health sciences, though this complex relationship has yet to be fully elucidated. Specifically, in studies on fear of crime and its influence on behavior, a variety of definitions and methods have been employed. This situation has yielded insights, as well as inconsistencies. In the past decade, Geographic Information Systems (GIS) has been added to this methodological mix, though it too has contributed limited understanding of the environmental perception-behavior nexus. During this time, some scholars have integrated a traditional technique for accessing environmental perception, the sketch map, with this newer technology. This article provides a review and critical assessment of the way GIS has been used to understand fear of crime, specifically through the integration of sketch maps. This focus is framed by an overview of substantive and methodological concerns and concludes with a discussion of continued research needs. As behavioral responses to fear of crime are acknowledged to impact physical and mental health and overall well-being, in addition to the viability of neighborhoods, research in this area will continue apace. However, for integration of sketch maps in GIS to be a valuable methodological contributor to this line of inquiry, users of the approach must understand its complexities. This article outlines these issues so that they may be considered in future research and may improve the ability for this approach to yield new understanding of fear of crime.  相似文献   

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