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511.
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.  相似文献   
512.
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.  相似文献   
513.
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.  相似文献   
514.
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。  相似文献   
515.
为满足皇藏峪国家森林公园规划建设对大比例尺地形图的迫切需求并针对测区的实际地形地貌情况,本文提出采用无人机低空摄影测量和工程测量相结合的混合测图方法完成区域的基础地形图测绘,对其基本流程、技术关键及实施效果进行了详细的总结和分析。基础测绘成果满足了实际规划建设的需要,通过不同方法的优势互补既保证了成图精度又降低了作业强度。  相似文献   
516.
基于城市交通与城市形态结构的密切关系,本文探讨了环形城市形态下的城市交通网模型,并提出了结合大众出行认知特征的城市交通最优路径规划方法。为检验本文方法的有效性,利用成都市路网数据对本方法与传统路径规划方法进行了对比实验,结果表明本文方法所规划路径更适应实际状况,可有效地降低时间消耗、较好地符合层次空间推理机制。  相似文献   
517.
This article traces how maps aided the conceptualization and ensuing debate over one of the first inherently spatial and multiscale environmental issues, acid rain. Through interviews with early acid rain ecologists and a critical cartographic analysis of printed maps, we show that mapping was central for constructing this environmental issue. Rather than static representations of a scientific reality, acid rain maps were interconnected and relational processes that operated within political and economic discourses. Accordingly, we suggest that increased critical engagement and participation with the process of mapping can productively aid dialog on many issues, including other current multiscale environmental issues, such as climate change.  相似文献   
518.

In this paper we summarize five experiments that were designed to investigate how tactile maps contribute to the cognitive maps of people with visual impairments. In two experiments we demonstrated that tactile maps can contribute to peoples' ability to learn a route through an unfamiliar area. From the results of two further studies, we argue that compared to people with sight, people with visual impairments have greater difficulty encoding information from a map. We considered this directly in a fifth experiment by investigating how people with visual impairments search and learn a map. We found that they used less efficient strategies than people with sight. We conclude that tactile maps are an important source of geographical information when people need to learn about new environments, but we also point out that to benefit most from tactile maps people need to encode the map information as effectively as possible. As people with visual impairments do not always use the most appropriate encoding strategies we suggest that tactile map users might benefit from greater experience and training in map encoding strategies.  相似文献   
519.

This work examines the use of an annually updated metropolitan data system as a tool for evaluating benign racial location policies during the first year of the Section 8 Existing Rent Supplement program. Case-study evidence shows that the rent supplement program (with benign locational policies) is ineffective in reducing the isolation faced by minority groups, and that the information used to monitor compliance of the program with benign locational policies lags badly behind the true state of affairs. As a result, new areas of racial concentration have been encouraged and augmented.  相似文献   
520.

Geographic Software Reviewed in this article:

APPLEPIPS

IBM EDUCATIONAL SOFTWARE SERIES: EARTH SCIENCE SERIES. Moisture in the Atmosphere, Hydrologic Cycle, Surface Water Ground Water

MINI-MAX

MULTIMAP. Barry R. Cohen. Planning Data Systems

WORLD GEOGRAPHY SERIES, U.S. GEOGRAPHY QUIZ, U.S. GEOGRAPHY ADVENTURE  相似文献   
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