The Journal of Geomatics and Information Science of Wuhan University as an open journal, relies on the advantages of discipline of engineering surveying and mapping of China. It's aiming to be one of excellent Chinese Surveying Journals. The Journal mainly publishes research achievements on Digital Photogrammetry, Remote Sensing, Cartology and Geographical Information Systems, Satellite Geodesy, Physical Geodesy and Geodynamics, Surveying Engineering and Image and Graphics etc.
Objectives: The central time-space maps deform the map space to visualize the one-to-many time distance, which can intuitively reflect the distance changes due to the influence of a traffic system. The core of the central time-space map construction is to calculate the non-control points’ locations based on the control points’ displacements. Displacement is a basic operation in cartographic generalization and many approaches have been developed. Methods: We model the central time-space map construction as a problem of displacement in cartographic generalization, use the relative neighborhood graph to express the proximity relations between the points, and the initial forces on the points are computed based on the control points’ displacements. And the Snake model is applied iteratively based on the built graph to obtain the new locations of all points, post operations are also applied to avoid topology errors in the iterative process. Results and Conclusions: Compared to the existing approaches, the proposed method can reduce the topology errors and improve the shape similarity for the deformed boundaries, and can better avoid topology errors and maintain the local morphologies.
Cartography is a subject whose development was partially restricted due to historical conditions. Compared with the traditional map, driven by new technology and new demands, the mapping objects, representation form, perception channel and user role of maps have all undergone significant changes in the information and communication technology (ICT) era. Therefore, the theoretical framework of cartography needs to be further adapted to the ICT era. This paper firstly analyzes the main characteristics of maps in the ICT era, then discusses the concepts and the scope of representation of modern maps in the new era, and finally tries to build the framework of modern maps including the representation object, information abstraction, map representation, and map outcomes. This study is expected to clarify the boundary of extended connotation of cartography research and provide corresponding support for the future development of cartography.
Style transfer which originates from computer graphics has attracted broader attention in the field of cartography, considerable efforts have been made on cartographic style transfer algorithms and experimental evaluation. However, it also suffers from unclear demarcation of map style, and lack of evaluation of style transfer results. Therefore, firstly, this paper conceptually analyzes the idea of map style and the applicable scenarios of styled maps. Then, we review existing style transfer methods, and categorize available style transfer methods into three groups and compare them with details: Probability statistics-based, content-based, and neural network-based. We also discuss three major types of map style transfer methods: Image to map, remote sensing imagery to map, and image to relief shading. And we compare the advantages and disadvantages of style transfer with vector and raster maps. Finally, we envision the future research of map style transfer in terms of three possible research questions: How to select reference images, how to evaluate style transfer results, and how to integrate style transfer into map design process.
With the advancement of information and communication technology (ICT), a large number of new visualization types and techniques of map representation have been developed, and the term of pan map is proposed due to these new cartography visualizations. However, the map design and production still greatly depend on map makers’ experiences and professional skill, which cannot meet new requirement in ICT era. In order to enhance the objective and automatic levels in the process of map design and production in information era, and keep developing of map theories with the new techniques of cartography visualization, this paper aims to develop the visualization mechanism of pan-maps representations. In this paper, the relationships between requirements of pan-map representations and visualization dimension types are constructed based on visualization dimension system and map functions. An analysis on the typical map visualization of different visualization dimension types has been conducted. The visualization mechanism of pan-maps has been constructed and follows the strategy “analysis of representation requirements → combination of visualization dimensions → determination of visualization representation types → map visualization”. This study is helpful to the developments of cartography research and applications, the popular map design, representation, and production.
This paper discusses the cognitive connotation of deep mapping. It attempts to consider deep mapping as an interdisciplinary research field, a combination of neuroscience and cartography, and a connection between brain mapping and geographic mapping. Recent developments in neuroscience, specifically the discovery of spatial cells such as place cells and grid cells, have provided a neuroscientific foundation for studying deep mapping. This paper proposes a conceptual model of deep mapping to establish the relationship between spatial cell properties and map functions (such as map scale, map measurement, map projection, and navigation), and to elucidate the neural mechanism of maps by analyzing an abundance of neuroscience literature. This study of deep mapping aims to increase understanding of the nature of maps, enrich cartographic theories, encourage the integration of cartography and artificial intelligence, and expand their applications.
Objectives: In the case of uneven distribution of map features, the density difference breaks the visual balance and reduces the beauty of the map. A large number of spatial features are concentrated in the small area, resulting in the contradiction between the display of features and the size of the area. Map details are not prominent, which increases difficulties in obtaining spatial information and is not conducive to decision analysis. The uneven distribution of feature density in mapping area increases the difficulty of map expression. Conventional map expression cannot solve the problem of visual imbalance. Methods: Based on Gastner-Newman cartogram algorithm, this paper proposes a map transformation algorithm that balances the feature density and achieve consistent public perception. Various cartograms can be generated through five steps: Designing deformation unit scales, configuring density weight combination of features, applying linear diffusion equation, constructing deformation grids, and mapping discrete control points. Results: Taking Qingxiu district of Nanning city, China as the research area, we select two scale deformation units of subdistrict and custom grid, and configure density weights with different combinations of point of interest and road network geometry features to generate various cartograms. The deformation measurement values of the deformation map are calculated respectively. After cognitive experiments, 56 questionnaires were obtained. Regarding the morphological control of the administrative map of Qingxiu District in Nanning, the parameters configurations should be controlled as in Sperimeter > 0.975, Sperimeter area ratio > 0.961 and Sshape ratio > 0.966. In this way, public cognition can be consistent. Conclusions: This study provides a new idea to solve the problem of the uneven density of map features. The deformed map reaches visual balance. The area where the original features are dense increases while the area where the features are sparse decreases. By adjusting the deformation weight parameters to maintain the consistency of public map cognition. Subsequently, we will further study how to determine the optimal parameter combination to achieve the optimal deformation expression and cognitive effect.
Objectives: The structure of the tourism flow network is significant for understanding the choices of tourists and the role of attractions in the network. The previous studies mainly focus on the structure of the tourism flow network of all tourists. However, the analysis on the disparities of tourism flow network for different tourists is still lack in the thorough research. Therefore, we analyze the tourism flow networks constructed by different types of tourism routes from online travel notes. Methods: Based on the online travel notes, the text mining and social network analysis methods are used to construct and analyze tourism flow networks. Firstly, we use text mining to extract the multi-dimensional preferences of tourists, and cluster tourists into different groups. Secondly, the destination sequences of different tourist groups are used to construct various tourist flow networks. Finally, the structural characteristics of these tourism flow networks and the role of each destination node are analyzed from multiple perspectives. Results: The experiment takes Yunnan Province as the study area, and the tourists travelled in Yunnan in 2019 are clustered into five groups, then five travel flow networks are constructed. The results show that the tourism flow network structures of five clusters of tourists are distinct, demonstrating the disparities of spatial interaction patterns among travel destinations and different degrees of network centralization. The travel destinations of cost sensitive and time sensitive tourists are primarily a few popular attractions and some attractions around them. The networks of these two types of tourists show a single-core structure. As for other types of tourists, their travel destinations are more diverse and their travel routes have a larger spatial span. The networks of these types of tourists present a typical multi-core structure. Some travel destinations like Lugu Lake, Xizhou, and Dian Lake take opposite roles in the tourism flow networks of different clusters of tourists. Conclusions: Our research is helpful for tourism management department to clarify the characteristics of tourism flows and optimize the cooperation mechanism of travel destinations in the tourism network.
Objectives: With the increasing application of tag maps, there is an urgent need for research on the evaluation of tag weight expression strategies. Tag weight differences in tag maps are usually reflected by different font sizes. One of the common strategies is evaluated, where the sequence of font sizes is an arithmetic progression. Methods: The five countries with different, representative shapes are selected as study cases. Five corresponding tag maps are produced by randomly generated tags in alphabetical order from left to right and top to bottom. On this basis, a controlled experiment is conducted. Two application scenarios of unpurposed free browsing and purposeful reading analysis are set, and tag selection, recognition/search, recalling, and subjective evaluation tasks are assigned. The subjects’ eye movement data and some other derived data are collected and statistically analyzed by the Kruskal-Wallis test and Mann-Whitney U test methods. Results: The results show that: (1) Tags of different sizes do not show significant differences in terms of visual salience, visual attractiveness, weight recalling and search efficiency, reading efficiency, and cognitive load in recognition/search tasks. (2) Tags with font size at the upper level are easier to be recognized/searched and of higher interest to subjects than those with font size at the lower level, but it does not mean that tags with larger size are more likely to be recognized/searched and of higher interest to subjects. (3) The overall evaluation of tag maps using font size strategy of an arithmetic progression is at a good level. Conclusions: The paper is helpful for map designers to further understand the characteristics of font size strategy. The font size is not a panacea in the tag weight expression of tag maps. In addition to font size, tag weight differences in tag maps can be shown by combining other visual attributes such as brightness, color, typeface, etc., or accompanying auxiliary charts according to the actual application. The interaction of the shape, area, the density of tags, and other visual attributes with the font size and some other font size strategies need to be studied for different users.
Extended reality (XR), which covers augmented reality (AR), virtual reality (VR), and mixed reality (MR), serves geospatial applications well. Human’ s perception and cognition with XR has been a topic of continuous research and development for decades. With the emergence of “metaverse”, this topic has attracted more and more researchers. This paper gives an overview of current progresses of XR and geospatial learning with an emphasis of its necessity. More specifically, we summarize the state of the art and trends of using VR and AR in geospatial cognition studies, the common research methods, devices, and tasks, with the aim to provide researchers with practical references. We also present a number of challenges and encourage cartography to participate in the XR development.
Objectives: In the transferring process from the modern society to the post-modern society, information is transmitted via We Media, in which the maps that are made by public users and map enthusiasts is not at high accuracy, and the expressions of the maps are diversified. WeMap is a kind of public-made maps, aiming to improve the map expressions to avoid the problems generated due to the lack of spatial cognitive knowledge, and to focus on the expressions of the map users’ subjective information. Unlike the traditional maps, WeMap aims to express geographical features and phenomena from multiple perspectives and dimensions. This paper examine the origins of the above characteristics from the postmodern philosophy perspective. Methods: Metaphoring maps and language, taking postmodern philosophical methodologies such as embodied cognitive view, prototype category theory, and decentralism of cognitive linguistics as tools, this paper critically analyzes and reconstructs the fundamental problems including spatial cognition, information classification, and cartographic expression of traditional maps, and forms the conceptual framework of WeMap with the characteristics of postmodern philosophy. Results: WeMap cognitive process model was proposed, consisting of two processes: Map making process which can be summarized as mental image-image schema-prototype-category-geographic knowledge-WeMap, and the map reading process which can be described as visual representation-visual feature-semantic and spatial relationship cognitive map-spatial analysis-spatial behavior. The cognitive hierarchy model of WeMaps may be classified into six levels (from IS1 to IS6) by the image schema. IS1 is suitable for most of public users who own the basic body image schema and it corresponds to the lowest cognitive ability, while IS2, IS3, IS4, IS5and IS6 correspond to more advanced cognition abilities. The information classification of WeMap coincides with prototype category theory which can be realized according to the principle of achieving commonness with prototype and compatibility with category. WeMap advocates pluralism which embodies in fuzzy map projections, various forms of map symbols, and even the opposite generalization standards compare to traditional maps. Conclusions: WeMap is a new map form in the era of We Media whose cognitive model, classification principle, and map expressions coincide with the ideas of embodied cognitive view, prototype category and decentralism of postmodern philosophy. The philosophical basis of traditional map is more inclined to metaphysical mechanical objectivism. Although it recognizes the role of human cognition in map making and use, the human here refers to map experts. Maps can only be developed under the design of map experts, which is difficult to give full play to the linguistic potential of maps. Map theories, such as adaptive maps and crowdsourcing maps, have begun to pay attention to the transformation of their philosophical basis, emphasizing the transfer of the main body of cartography and map use from map experts to public users, but they are still limited by the design knowledge and ability of map experts. WeMap aims to put map experts and public users on an equal position, fully respect the individual geospatial cognitive needs and habits of each map user, the decentralization of WeMap conforms to the development trend of human post-modernist philosophy.
