City road networks have been extensively studied for their social significance or to quantify their connections and centralities, but often their geographical origin is forgotten. This work focuses on the spatial-geographical and geometrical aspects of the road network skeleton. Following previous work, a multi-scale object, the way, is constructed, based only on the local geometry at road crossings. The best method to reconstruct significant elements is investigated. The results show that this object is geographically meaningful, with many particular characteristics. A new indicator, structurality, is introduced and compared with previous indicators, on the cities of Paris and Avignon. Structurality appears to be stable over the borders of the map sample, and is able to reveal the underlying coherence of the road network. This stability can be interpreted as coming from the particular way the network developed in time, and was later preserved. This link with the historical development of the cites, which deserves to be further studied, is exemplified in the cases of Villers-sur-Mer (France) and Manaus (Brazil). The construction method, the results, and their potential meaning are discussed in detail so that they can be used in various related disciplines, such as sociology, town planning, geomatics, and physics.
Road networks result from a subtle balance between geographical coverage and rapid access to strategic points. An understanding of their structure is fundamental when it comes to evaluating and improving territorial accessibility. This study is designed to provide insight into the progressive structuring of territorial patterns by analyzing the evolution of road networks. Studying road network morphogenesis requires geohistorical data, provided here by historical maps from which earlier road networks can be digitized. A hypergraph is constructed from these networks by combining road segments into “ways” on the basis of a method for defining the continuity of road segments. Next, indicators are computed for these ways based on topological and geometrical features. The road patterns of three cities in the Burgundy Franche-Comte region of France (Dijon, Besançon, and Pontarlier) at three historical periods (the 18th, 19th, and twentieth centuries) are then analyzed. In this manner, their topological features and centrality characteristics can be compared from snapshots at different times and places. The innovative method proposed in this paper helps us to read features of the road patterns accurately and to make simple interpretations. It can be applied to any territory for which data is available. The results highlight the underlying structure of the three cities, reveal information about the history and the functioning of the networks, and give preliminary insights into the morphogenesis of those cities. Prospectively this work aims to identify the mechanisms that drive change in road networks. Detecting stability or variation in indicators over time can help in identifying similar behavior, despite geographic and cultural distances, as well as evolution mechanisms linked to specificities of each city. The study of road network morphogenesis can make a major contribution to understanding how road network structure affects accessibility and mobility.
Despite the crucial importance of maritime transport for world trade and economic development, dedicated tools to map the evolution of vessel movements remain lacking.Such movements, especially those recorded by the maritime insurance company Lloyd's List, represent the only available information documenting the changing spatial distribution of the world's shipping routes in the last century or so. This chapter tackles the lacuna head on by discussing how this particular type of shipping data can be accurately represented on a map (see Chapter 1 for a review of the field). Such an exercise poses specific issues in terms of geovisualization, as it necessitates, among other developments, the creation of a virtual maritime grid to which port nodes and their mutual vessel flows are assigned. Beyond geomatics, this research is also an opportunity to shed new light on a vibrant research question in maritime history, namely how steam has replaced sail shipping in space and time.We extracted snapshots of global maritime flows every five years from the Lloyd's Shipping Index between 1890 and 1925 in order to test the capacity of the geoportal to visualize such flows, and at the same time verify the spatio-temporal evolution of a bi-layered maritime network. The remainder of this chapter is organized as follows: the next section discusses the scarcity of maritime data cartography until recent years in the light of general knowledge on flow mapping in geography and elsewhere. It is followed by a description of how vessel movement data had been incorporated into a dedicated visualization system. Lastly, it provides the first-ever cartographies of such movements while discussing the gaps between our results and the existing literature on the transition from sail to steam shipping.Conclusions point to a number of ways how the visualization system may be improved in the future, and how it can contribute toward addressing numerous other issues in global transport studies in general.
Distribution électronique Cairn.info pour Université Gustave Eiffel. © Université Gustave Eiffel. Tous droits réservés pour tous pays.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.