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The adaptive composite map projection technique changes the projection to minimize distortion for the geographic area shown on a map. This article improves the transition between the Lambert azimuthal projection and the transverse equal-area cylindrical projection that are used by adaptive composite projections for portrait-format maps. Originally, a transverse Albers conic projection was suggested for transforming between these two projections, resulting in graticules that are not symmetric relative to the central meridian. We propose the alternative transverse Wagner transformation between the two projections and provide equations and parameters for the transition. The suggested technique results in a graticule that is symmetric relative to the central meridian, and a map transformation that is visually continuous with changing map scale. [ABSTRACT FROM AUTHOR]

The novel coronavirus (COVID-19) pandemic is a public health emergency of international concern that caused disaster consequences all over the world. To mitigate and manage the pandemic, geographical information systems (GIS)-based spatial analysis has been used in a key role. To this aim, many GIS-based maps are produced by many national and international institutions. However, the produced maps are prepared by conventional methods and the features in these maps representing by their areal size. This paper proposes the diffusion-based cartograms for visualization of the COVID-19 outbreak. In the study, daily country-level data of the first 150 days of the COVID-19 outbreak were obtained from WHO, and the spread and spatial patterns of the epidemic were presented according to the number of confirmed cases and deaths. As a result of the study, it was observed that the cartogram is a powerful visualization tool and superior to the classical methods. [ABSTRACT FROM AUTHOR]

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Geospatial data are now widely available to the general public thanks to geoportals and online mapping platforms. However, creating a map involves more than just combining data layers. Thus we develop cartographic functions for geoportals to support better visual hierarchy in user map mashups. This includes a couple of preparatory steps followed by a smart cartographic background symbolization derived from the original layer style. We evaluate different approaches to background symbolization: greyscale, desaturation, and smart background. The different background symbolization methods are analysed with two concrete map examples and evaluated with a survey. The smart background symbolization developed in this work improves the visual hierarchy of the map mashup by reducing the visual importance of the background layers. [ABSTRACT FROM AUTHOR]

Trajectory analysis has attracted growing attention in the research field of geography. Beyond traditional moving object trajectories, another type of trajectory exists in which the coordinates are object attributes rather than geographical coordinates. In this paper, a framework to analyse these so-called attribute trajectories is proposed that uses four techniques typically employed in the analysis of moving object trajectories: the Reeb graph, the similarity matrix, the convoy and the mega-convoy. The Reeb graph provides the ability to visualise the temporal dynamics of attribute similarities. The similarity matrix is a supplement of the Reeb graph whose purpose is to visualise the pairwise similarities among the attributes. Moreover, the similarity matrix forms a basis for clustering. The convoy highlights objects whose attributes remain similar for a sufficiently long period. The mega-convoy reduces the number of convoys and reveals their evolutionary histories by merging overlapping convoys. A small real-world meteorological dataset is used as an example to illustrate the attribute trajectory analysis framework and the techniques. This paper aims to form a starting point for applying trajectory analysis techniques in many research fields. [ABSTRACT FROM AUTHOR]

This paper examines the spatial patterns of non-work activities for 34 drivers in the Southeast Michigan region. Capitalizing upon a unique global positioning systems (GPS) dataset and GIS visualization techniques, this study quantifies the spatial distributions of non-work activities for drivers with different commuting distances, and for non-work activities that are chained in different types of travel (commute travel vs. non-commute travel). We find a strong dependence of non-work activity locations on commuting distances, and an influence of commuting routes on non-work activities chained in all types of travel. The results underline the importance of commuting routes in shaping the spatial configuration of non-work activities. [ABSTRACT FROM AUTHOR]