Editorial

This article presents research that implements a fully automated workflow to generalize a 1:50k map from 1:10k data. This is the first time that a complete topographic map has been generalized without any human interaction. More noteworthy is that the resulting map is good enough to replace the existing map. Specifications for the automated process were established as part of this research.

Replication of the existing map was not the aim, because feasibility of automated generalization is better when compliance with traditional generalizations rules is loosened and alternate approaches are acceptable. Indeed, users valued the currency and relevancy of geographical information more than complying with all existing cartographic guidelines. The development of the workflow thus started with the creation of a test map with automated generalization operations. The reason for the test map was to show what is technologically possible and to refine the results based on iterative users’ evaluation. The generalization operations (200 in total) containing the relevant algorithms and parameter values were developed and implemented in one model. Particular effort was made to enrich the source data in order to improve the results. The model is context aware which means it is able to apply different algorithms or adjust parameter values in accordance with a specific area. The result of the research is a fully automated generalization workflow that produces a countrywide map at scale 1:50k from 1:10k data in 50 hours.

A fully automated workflow may be the only way to produce flexible and on-demand products; consequently, the results were implemented as a new production line in 2013. Issues for further research have been identified.     

A CO-ORDINATE SYSTEM FOR STUDYING INTERACTIONS IN THE PRIMARY CHRISTALLER LATTICE∗

The co-ordinate system (x, y) for the triangular Christaller lattice is generalized by the addition of a third, dependent, z-axis. The extended system yields the lattice distances between lattice points, whereas the original system yields only the plane Euclidean distance.     

The Role Of The Geographer On Multidisciplinary Resource Surveys

Turning and turning in the widening gyre The falcon cannot hear the falconer; Things fall apart; the centre cannot hold; Mere anarchy is loosed upon the world ….

“The Second Coming,” W. B. Yeats 1921     

Interpreting maps through the eyes of expert and novice users

The experiments described in this article combine response time measurements and eye movement data to gain insight into the users' cognitive processes while working with dynamic and interactive maps. Experts and novices participated in a user study with a ‘between user’ design. Twenty screen maps were presented in a random order to each participant, on which he had to execute a visual search. The combined information of the button actions and eye tracker reveals that both user groups showed a similar pattern in the time intervals needed to locate the subsequent names. From this pattern, information about the users' cognitive load could be derived: use of working memory, learning effect and so on. Moreover, the response times also showed that experts were significantly faster in finding the names in the map image. This is further explained by the eye movement metrics: experts had significantly shorter fixations and more fixations per second meaning that they could interpret a larger part of the map in the same amount of time. As a consequence, they could locate objects in the map image more efficiently and thus faster.     

Conceptualising the geographic world: the dimensions of negotiation in crowdsourced cartography

In crowdsourced cartographic projects, mappers coordinate their efforts through online tools to produce digital geospatial artefacts, such as maps and gazetteers, which were once the exclusive territory of professional surveyors and cartographers. In order to produce meaningful and coherent data, contributors need to negotiate a shared conceptualisation that defines the domain concepts, such as road, building, train station, forest and lake, enabling the communication of geographic knowledge. Considering the OpenStreetMap Wiki website as a case study, this article investigates the nature of this negotiation, driven by a small group of mappers in a context of high contribution inequality. Despite the apparent consensus on the conceptualisation, the negotiation keeps unfolding in a tension between alternative representations, which are often incommensurable, i.e., hard to integrate and reconcile. In this study, we identify six complementary dimensions of incommensurability that recur in the negotiation: (1) ontology, (2) cartography, (3) culture and language, (4) lexical definitions, (5) granularity, and (6) semantic overload and duplication.     

城市大比例尺数字影像地图的研制

城市数字影像地图的制作与应用是城市遥感和数字城市建设的重要环节 ,是城市基础空间数据集和城市GIS的重要组成部分 ,其在城市建设和发展中的地位与作用日益高涨。本文就城市大比例尺数字影像地图制作工艺、生产平台、比例尺系列、航摄要求、控制数据、质量要求和应用模式等进行了探讨 ,对比了数字摄影测量系统和商用遥感图像处理系统在城市影像制图中的应用方式 ,认为在现阶段 ,在城市测量单位 ,以基于单片微分纠正原理的图像处理软件为主要制作平台 ,集成其它测量和制图系统以及既有控制数据和地形数据进行规模化的影像图生产具有极大的优势和推广应用前景.并以生产实例对优势和前景进行了说明。     

基于核密度估计的点群密度制图应用研究

随着信息技术的发展,点状专题数据激增,需要突破传统制图方法的表达局限,利用海量点群数据对专题信息进行快速、直观、综合的制图表达。文中以南京市银行的ATM网点数据以及全国KTV营业点分布为制图数据源,探讨了点群数据核密度估计图以及三维核密度曲面图的制作方法,并对其中的关键技术作了深入的研究。研究表明,基于核密度估计的网点密度制图方法,消除了边界分隔对密度计算精度的影响,能更好反映点群数据的空间分布密度、区域差异、动态变化等特征,具备更丰富的表现力。     

Mixing Methods and Triangulating Results to Study the Influence of Panning on Map Users’ Attentive Behaviour

The general aim of this paper is to evaluate the influence of panning on the map user’s (attentive) behaviour, using a mixed methods approach. A user study was conducted in which participants – with an expertise in cartography – had to execute four tasks in Google Maps, using only a panning operation. During the first two tasks, participants had to follow a predefined route; during the latter two tasks they had to locate Belgium on a less detailed scale level. A strong task-related interactive behaviour was revealed by the participants’ mouse action and eye movements. Furthermore, the attentive behaviour was influenced by the type of view (map or satellite) and whether it occurs while performing the panning operation. The georeferenced eye movements were imported in a GIS for spatial analysis. Based on these spatial queries, we discovered that the duration of the fixations was associated by their location on the map.