COMPARING DISTORTION ON SKETCH MAPS AND MDS CONFIGURATIONS*

The mental images on which an individual bases spatial decisions are often distorted versions of real-world geography. Distortion in these images is studied by extracting paired distance estimates and by requesting a sketch of a place drawn from memory. Reliance upon either technique to elicit large-scale spatial information assumes that distortion in the congnitive map is not introduced by the technique (sketching or configuration) used to construct it. Both techniques have been used in this study to produce cognitive maps for a common set of landmarks in Seattle. Map distortions are analyzed and compared to determine that significant differences result from the technique used.     

A new pseudocylindrical equal-area projection for adaptive composite map projections

The recently introduced adaptive composite map projection technique changes the projection to the geographic area shown on a map. It is meant as a replacement for the commonly used web Mercator projection, which grossly distorts areas when representing the entire world. The original equal-area version of the adaptive composite map projection technique uses the Lambert azimuthal projection for regional maps and three alternative projections for world maps. Adaptive composite map projections can include a variety of other equal-area projections when the transformation between the Lambert azimuthal and the world projections uses Wagner’s method. To select the most suitable pseudocylindrical projection, the distortion characteristics of a pseudocylindrical projection family are analyzed, and a user study among experts in the area of map projections is carried out. Based on the results of the distortion analysis and the user study, a new pseudocylindrical projection is recommended for extending adaptive composite map projections. The new projection is equal-area throughout the transformation to the Lambert azimuthal projection and has better distortion characteristics then small-scale projections currently included in the adaptive composite map projection technique.     

Comparing historical and contemporary maps - a methodological framework for a cartographic map comparison applied to Swiss maps

Topographic maps are powerful tools for the purpose of identifying land use and cover change (LUCC) as they are among the most reliable representations of past landscapes for the time prior to the existence of aerial photography. In light of the increased availability of historical maps, we argue that there is a need for a standardized process to assess map comparability in a systematic way in order to avoid, or at least minimize, the detection of spurious landscape changes due to incompatible map series. A full understanding of map quality, background and error distributions is fundamental to attain reliable LUCC results. The conceptual framework presented in this study considers the context, distortion and cartographic generalization of topographic maps. Furthermore, it includes an approach to homogenize the level of generalization of landscape elements (e.g. forests) from maps with different scales. To demonstrate its application, we assessed the comparability of seven topographic maps from Canton Zurich covering a time span of 336 years (1664–2000). Overall, for the maps of Canton Zurich, a wall-to-wall comparison of forest cover based on the topographic maps presented here can be problematic for the oldest map from 1664. Based on the results, a wall-to-wall comparison with the later maps is not recommended, due to its substantial distortion. Yet, after re-generalization of natural landscape elements, such as forests, a comparison based on landscape indices is possible, even for the oldest map. Furthermore, our results demonstrate that maps from the mid-19^th century onward possess an acceptable level of accuracy. This framework can be applied to a wide range of maps at regional, national, or global levels, providing the opportunity to look at land cover history over multiple centuries.     

Assessing the Accuracy of The Map of the Prefectural Capital of 1261 Using Geographic Information Systems

This paper explores the application of geographic information systems (GIS) in the evaluation of the accuracy of early maps through a case study of The Map of the Prefectural Capital of 1261. The evaluation of the accuracy of early maps is an important aspect of the study of the history of cartography, but no standard methodology has been generally accepted. The purpose of this paper is to assess the positional accuracy and the relative relations of the spatial objects on The Map of the Prefectural Capital using GIS. The procedure of the study includes identification of locations of the points and features of The Map of the Prefectural Capital on a modern base map, digitization of the early map and the modern base map, overlays of the digitized early map and modern base map, and an analysis of the absolute and relative distortion of the early map. The results of the analysis show that The Map of the Prefectural Capital of 1261 is reasonably accurate considering the technical ability of the thirteenth century, although it contains a considerable amount of positional displacement. In contrast to the amount of positional displacement, the relative relations among the objects are depicted much more precisely.     

北京市电子地图集的设计与技术实现

在电子地图设计的研究中,“用户界面设计”、“三维景观表达”、“多媒体的使用”、“动态注记”、“图形冲突”和“屏幕地图的交互功能”等都是至关重要的问题。然而在电子地图日益普及的今天,对这些问题的认识还需进一步的研究。本文结合《北京市电子地图集》的创作实践,详细讨论了电子图集的功能设计和界面设计,对以上问题提出了切实可行的的解决方案,并给出了较为理想的试验结果     

Fluid Borders: Rethinking Historical Geography and Fixed Map Boundaries in Contested Regions

This article introduces a quantitative methodology for analyzing contested map borders. The article applies the new analytical technique to a data set of thirty maps showing Bulgaria in ca. 800 CE, a disputed state and period in medieval historiography with relevance to modern national politics and territorial claims. Based on the data set, we generate a series of new maps that make explicit the fluid medieval boundaries and general disagreement among geographers and historiographers. Our analysis begins with a simple point-in-polygon procedure to create a majority map that depicts the points included within the borders of the Bulgarian polity in sixteen or more of the maps (>50 percent). The majority map is then combined with percentage maps, confidence interval map boundaries, and cluster maps. The confidence interval maps are created via a spatial bootstrapping procedure and measure the uncertainty in the majority map. The cluster maps are developed via a radial basis function and provide insight into the potential affectivity based on the cartographers' countries of origin. The final map reflects the general modern consensus of the borders of the Bulgarian polity around 800 CE. Besides its quantitative contribution to medieval and modern cartographic, historiographical, and political debates, this article has developed a widely applicable methodology for synthesizing map borders and territories in cases of cartographic disagreement.     

广东省1:50万TM假彩色卫星影像图的研制

介绍采用两种不同投影系统的卫星资料制作１：５０万ＴＭ卫星影像图的基本工艺及关键技术,（１０对ＴＭ卫星底片进行密度测定和反差分析,（２）卫星像片平面位置误差赋和控制;（３）卫星像片彩色合成色调协调一致控制,在此基础上分析论述了ＴＭ卫星影像图的特点及其在地理学上的应用。     

A QUANTITATIVE-COMPARATIVE APPROACH TO ANALYSIS OF DISTORTION IN MENTAL MAPS

A quantitative procedure for analyzing and comparing distortion in mental maps is presented. Using a microcomputer and digitizer, and by developing a distortion index, comparisons are made by direct analysis of mental maps. A case study of the mental maps of Israel of high school and university students showed a tendency to generalize shape to simple geometric forms, with foreshortening of north-south lines and exaggeration of east-west distances.     

小城镇信息图谱初探

小城镇建设将成为我国农村经济发展的一种重要模式。为了引导小城镇的可持续发展,有必要对小城镇演变的内在规律作深入研究。运用“图谱”的表达方式和GIS分析工具,从小城镇图谱的基本构成要素入手,对小城镇的群体空间、外部形态和内部结构的演变规律进行了探讨。并以泰州市城镇群、兰溪市永昌镇为例,作了实证研究。研究表明,采用图谱的表达方式有助于我们对城镇发展进行了历史总结、规律挖掘,客观地把握城镇的发展阶段,从而了解不同时期城镇工作的重点,以有的放矢地采取措施,部署长远规划。     

近现代时期若干北京古旧地图研究与数字化处理

本文介绍了若干幅 1 90 7年至 1 948年间由陆地测量总局等不同权威机构测绘、编制的古旧北京地图 ,为开展近现代时期北京城市地理、土地覆盖变迁研究、为古地图研究与利用提供参考。对古旧地图的应用及数字化技术处理进行了探讨。     

Data-Driven Index Overlay and Boolean Logic Mineral Prospectivity Modeling in Greenfields Exploration

Index overlay and Boolean logic are two techniques customarily applied for knowledge-driven modeling of prospectivity for mineral deposits, whereby weights of values in evidential maps and weights of every evidence map are assigned based on expert opinion. In the Boolean logic technique for mineral prospectivity modeling (MPM), threshold evidential values for creating binary maps are defined based on expert opinion as well. This practice of assigning weights based on expert opinion involves trial-and-error and introduces bias in evaluating relative importance of both evidential values and individual evidential maps. In this paper, we propose a data-driven index overlay MPM technique whereby weights of individual evidential maps are derived from data. We also propose a data-driven Boolean logic MPM technique, whereby thresholds for creating binary maps are defined based on data. For assigning weights and defining thresholds in these proposed data-driven MPM techniques, we applied a prediction-area plot from which we can estimate the predictive ability of each evidential map with respect to known mineral occurrences, and we use that predictive ability estimate to assign weights to evidential map and to select thresholds for generating binary predictor maps. To demonstrate these procedures, we applied them to an area in the Kerman province in southeast Iran as a MPM case study for porphyry-Cu deposits.     

Non-current data and geographical information systems A case for data retention

Inter-urban income disparities reflect differences between individual urban localities in the average incomes of their residents. The present paper discusses different ways of visualizing such disparities on thematic maps. The approach we propose is based on the transformation of distances between individual localities and a reference city (e.g. a major population centre of a country) in proportion to the actual differences in the income levels. The general principle of such a transformation is to bring closer to the reference city places with higher incomes, while moving away localities with low income levels. Three alternative approaches to the implementation of this transformation technique are discussed. According to the ‘actual distance’ method, the spatial ‘shift’ of a locality on the map is set proportional to both the relative difference in incomes and the aerial distance between a locality and the reference city. In the ‘proportional increment’ transformation, the distance between a locality and the reference city is adjusted by a parameter whose values are proportional to income disparities between the two. Lastly, according to the ‘concentric circle’ transformation, localities with identical levels of incomes are positioned at a certain distance from the reference city, forming concentric circles around it. Both advantages and disadvantages of these transformation techniques are discussed, and the ‘proportional increment’ method is chosen as the best-performing visualization technique. The performance of this technique is demonstrated using income data for urban localities in Israel in 1991 and 1999. As analysis indicates, the proposed method helps to illustrate both the existing patterns of inter-urban income disparities and their dynamics over time.     

Exploring spatial data uncertainties in land‐use change scenarios

This paper evaluates errors and uncertainties in representing landscapes that arise from different data rasterization methods, spatial resolutions, and downscaled land‐use change (LUC) scenarios. A vector LU dataset for Luxembourg (minimum mapping unit: 0.15 ha; year 2000) was used as the baseline reference map. This map was rasterized at three spatial resolutions using three cell class assignment methods. The landscape composition and configuration of these maps were compared. Four alternative scenarios of future LUC were also generated for the three resolutions using existing LUC scenarios and a statistical downscaling method creating 37 maps of LUC for the year 2050. These maps were compared in terms of composition and spatial configuration using simple metrics of landscape fragmentation and an analysis of variance (ANOVA). Differences in landscape composition and configuration between the three cell class assignment methods and the three spatial resolutions were found to be at least as large as the differences between the LUC scenarios. This occurred in spite of the large LUC projected by the scenarios. This demonstrates the importance of the rasterization method and the level of aggregation as a contribution to uncertainty when developing future LUC scenarios and in analysing landscape structure in ecological studies.     

GPS技术在滑坡监测中的应用

探讨了应用GPS技术进行滑坡监测的原则和方法，结合向阳技校滑坡的实际监测资料对这一方法进行了论证。并通过对几年来观测数据的综合分析，得出了滑坡体位移的大小和方向和对该地区地表以及位于滑坡体上的建筑物造成的影响，提出了滑坡预测模型，进而利用该模型和监测数据对滑坡进行了预报，从而对该地区的防灾工作具有重要的意义，也为GPS技术在变形监测中的应用提供了重要的参考价值。     

地学信息图谱研究及其应用

地学信息图谱综合了景观综合图的简洁性和数学模型的抽象性,它是现代空间技术与我国传统研究成果结合的产物,它可反演过去、预测未来。在分析地学信息图谱、生态系统发展战略、DLU土地利用战略、数学模型与地理信息系统集成等研究成果的基础上,提出了一个区域可持续发展虚拟系统。在这个虚拟系统中,如何将区域可持续发展的有关信息转换为征兆图、诊断图和实施图是其核心理论问题。数学模型计算机程序自动生成软件和开放式地理信息系统的研究成果表明,这些理论问题在不久的将来是可以解决的。也就是说,这个区域可持续发展虚拟系统的进一步研究,能够形成一个可操作的、实用的决策支持系统。     

A double continuous approach to visualization and analysis of categorical maps

A method to visualize multiple membership maps, called ‘Colour mixture’ (CM) is described and compared with alternative techniques: defuzzification and Pixel mixture. Six landform parameters were used to derive the landform classes using supervised fuzzy k-means classification. The continuous categorical map is derived by GIS calculations with colours, where colour values are considered to represent the taxonomic space spanned by the attribute variables. Coordinates of the nine class centres (landform facets) were first transformed from multivariate to two-dimensional attribute space using factor analysis, and then projected on the Hue Saturation Intensity (HSI) colourwheel. The taxonomic value was coded with the Hue and confusion with Saturation. To improve visual impression, saturation was replaced with whiteness. Classes that were closer in attribute space were merged into similar generic colours. The CM technique limits the derived mixed-colour map to seven generic hues independently of the total number of classes, which provides a basis for automated generalization. The confusion index derived from the mixed-colour map was used to derive primary boundaries and to locate areas of higher taxonomic confusion.     

基于社会地图的东莞市社会空间研究

既有社会空间研究以社会区研究居多,主要基于社会区理论和因子生态分析方法,较多考虑分析对象的社会属性而非空间特征,对社会空间的空间侧面刻画不足,其分析结果也常常被聚类人口的数据特征所左右。本文尝试基于社会地图方法,以人口普查数据和社会设施机构POI数据首先进行社会空间属性的归纳,制作社会地图,并以此为基础,采用归纳的方法渐进探索中国城市社会空间的特征。具体以东莞市为例,通过社会地图归纳方法将东莞市划分为3大类、11小类社会空间,并具体解析了多种社会空间要素组合类型。和既有基于社会区的分析结果相比,本文对各类社会要素在城市空间上的分布及其组合特征描述更为精细,其结果对认识中国社会空间特质及其后的社会空间政策制定更具参考意义。本文认为,基于社会地图的社会空间研究,有助于自下而上地发现有别于西方的中国城市社会空间特征和结构,也有助于建立基于中国的社会空间理论,值得进一步推广和尝试。     

Automation and evaluation of graduated dot maps

Dot mapping is a traditional method for visualizing quantitative data, but current automated dot mapping techniques are limited. The most common automated method places dots pseudo-randomly within enumeration areas, which can result in overlapping dots and very dense dot clusters for areas with large values. These issues affect users’ ability to estimate values. Graduated dot maps use dots with different sizes that represent different values. With graduated dot maps the number of dots on a map is smaller, reducing the likelihood of overlapping dots. This research introduces an automated method of generating graduated dot maps that arranges dots with blue-noise patterns to avoid overlap and uses clustering algorithms to replace densely packed dots with those of larger sizes. A user study comparing graduated dot maps, pseudo-random dot maps, blue-noise dot maps and proportional circle maps with almost 300 participants was conducted. Results indicate that map users can more accurately extract values from graduated dot maps than from the other map types. This is likely due to the smaller number of dots per enumeration area in graduated dot maps. Map users also appear to prefer graduated dot maps over other map types.     

基于手绘草图的北京居民认知地图变形及因素分析

认知地图是外界环境在人们头脑中的表征, 往往与现实地图不一致, 研究认知地图及 其变形对城市规划和建设具有重要意义。手绘草图是当前挖掘认知地图的一种主要方法。通 过问卷调查, 获得北京居民手绘草图样本, 分析草图中体现的北京城市意象要素。采用二维 回归(BR) 与标准偏差椭圆方法定量测度认知地图整体和局部的变形。对于二维回归计算出 的变形系数(DI) 进一步采用蒙特卡罗模拟计算其变形半径, 得出北京居民的认知地图平均变 形在2-3 km, 整体变形以二环为界, 内小外大, 并呈西南-东北斜向拉伸, 东西收缩的趋 势, 局部变形北部大于南部。个体的变形系数与对地标的熟悉程度负相关, 男性小于女性, 驾车者小于不驾车者, 日常活动范围越广、出行频率越高、居住时间越久、距离锚点越近的 被试认知变形越小。     

Thematic land-cover map assimilation and synthesis: the case of locating potential bioenergy feedstock in eastern Ontario,Canada

Insufficient spatial coverage of existing land-cover data is a common limitation to timely and effective spatial analysis. Achieving spatial completeness of land-cover data is the most challenging for large study areas which straddle ecological or administrative boundaries, and where individuals and agencies lack access to, and the means to process, raw data from which to derive spatially complete land-cover maps. In many cases, various sources of secondary data are available, so that land-cover map assimilation and synthesis can resolve this research problem. The following paper develops a reliable and repeatable framework for assimilating and synthesizing pre-classified data sets. Assimilation is achieved through data reformatting and map legend reconciliation in the context of a specific application. Individual maps are assessed for accuracy at various geographic scales and levels of thematic precision, with an emphasis on the ‘area of overlap’, in order to extract information that guides the synthesis process. The quality of the synthesized land-cover data set is evaluated using advanced accuracy assessment methods, including a measure describing the ‘magnitude of disagreement’. This method is applied to derive a seamless thematic map of the land cover of eastern Ontario from two disparate map series. The importance of assessing data quality throughout the process using multiple reference data sets is highlighted, and limitations of the method are discussed.