Using Space Syntax For Estimation Of Potential Disaster Indirect Economic Losses

The study of applicable network measures shows that Normalised Angular Choice can be used as criteria for selecting alternatives for minimizing indirect costs caused by road network damages. At the same time, this methodology cannot be used for monetizing indirect costs or identifying losses in different economic sectors. The study approach does not contradict the main theoretical approaches and it gives new opportunities for research on disasters recovery

Recent Developments and Future Trends in Volunteered Geographic Information Research: The Case of OpenStreetMap

User-generated content (UGC) platforms on the Internet have experienced a steep increase in data contributions in recent years. The ubiquitous usage of location-enabled devices, such as smartphones, allows contributors to share their geographic information on a number of selected online portals. The collected information is oftentimes referred to as volunteered geographic information (VGI). One of the most utilized, analyzed and cited VGI-platforms, with an increasing popularity over the past few years, is OpenStreetMap (OSM), whose main goal it is to create a freely available geographic database of the world. This paper presents a comprehensive overview of the latest developments in VGI research, focusing on its collaboratively collected geodata and corresponding contributor patterns. Additionally, trends in the realm of OSM research are discussed, highlighting which aspects need to be investigated more closely in the near future

From the cartographic gaze to contestatory cartographies

Rene Descartes declared in the 16th Century that the world was now dominated by the visual, a notion that would be seen as defining the Enlightenment (Descartes, cited in Potts, 2015). As the increased dominance of seeing and the desire to visualise the world cohered with the production of increasingly accurate tools of measurement and the advent of the printing press, cartography emerged as a discipline, often used as tool of oppression and dominance. Cartographic visualizations, afforded the creator, and user, a Gods eye view of the world. Following others (See Casas-Cortés et. al., 2013; Koch, 1998), this chapter refers to this way of seeing the world from above as the Cartographic Gaze. First, the chapter briefly examines the historical emergence of the Cartographic Gaze before turning to a discussion about how the proliferation of geographic imaging technologies and digital tools simultaneously further embedded this gaze into mapping practice, while also diffusing such practices of mapping to broader populations. Discussing the rise of participatory mapping and counter mapping under the rubric of contestatory cartographies, the chapter presents some of the challenges that face those attempting to create alternative maps of their worlds, and the ways in which they become entrapped by the pervasiveness of the Cartographic Gaze. We use the term participatory mapping to refer to methodologies for map-making based around the participation of those who the map will represent. And we employ the term counter mapping to reference those mapping practices that explicitly seek to expose and challenge power relations. In specific, we look at how the colonizing origins of the Cartographic Gaze limit what it is possible to do with these alternative mapping practices

Quality Assessment of the Canadian OpenStreetMap Road Networks

Volunteered geographic information (VGI) has been applied in many fields such as participatory planning, humanitarian relief and crisis management because of its cost-effectiveness. However, coverage and accuracy of VGI cannot be guaranteed. OpenStreetMap (OSM) is a popular VGI platform that allows users to create or edit maps using GPS-enabled devices or aerial imageries. The issue of geospatial data quality in OSM has become a trending research topic because of the large size of the dataset and the multiple channels of data access. The objective of this study is to examine the overall reliability of the Canadian OSM data. A systematic review is first presented to provide details on the quality evaluation process of OSM. A case study of London, Ontario is followed as an experimental analysis of completeness, positional accuracy and attribute accuracy of the OSM street networks. Next, a national study of the Canadian OSM data assesses the overall semantic accuracy and lineage in addition to the quality measures mentioned above. Results of the quality evaluation are compared with associated OSM provenance metadata to examine potential correlations. The Canadian OSM road networks were found to have comparable accuracy with the tested commercial database (DMTI). Although statistical analysis suggests that there are no significant relations between OSM accuracy and its editing history, the study presents the complex processes behind OSM contributions possibly influenced by data import and remote mapping. The findings of this thesis can potentially guide cartographic product selection for interested parties and offer a better understanding of future quality improvement in OSM

Positional accuracy assessment of the OpenStreetMap buildings layer through automatic homologous pairs detection: the method and a case study

OpenStreetMap (OSM) is currently the largest openly licensed collection of geospatial data. Being OSM increasingly exploited in a variety of applications, research has placed great attention on the assessment of its quality. This work focuses on assessing the quality of OSM buildings. While most of the studies available in literature are limited to the evaluation of OSM building completeness, this work proposes an original approach to assess the positional accuracy of OSM buildings based on comparison with a reference dataset. The comparison relies on a quasi-automated detection of homologous pairs on the two datasets. Based on the homologous pairs found, warping algorithms like e.g. affine transformations and multi-resolution splines can be applied to the OSM buildings to generate a new version having an optimal local match to the reference layer. A quality assessment of the OSM buildings of Milan Municipality (Northern Italy), having an area of about 180 km2, is then presented. After computing some measures of completeness, the algorithm based on homologous points is run using the building layer of the official vector cartography of Milan Municipality as the reference dataset. Approximately 100000 homologous points are found, which show a systematic translation of about 0.4 m on both the X and Y directions and a mean distance of about 0.8 m between the datasets. Besides its efficiency and high degree of automation, the algorithm generates a warped version of OSM buildings which, having by definition a closest match to the reference buildings, can be eventually integrated in the OSM database

Proceedings of the Academic Track at State of the Map 2020

Proceedings of the Academic Track at State of the Map 202

Proceedings of the Academic Track at the State of the Map 2020

Proceedings of the Academic Track at the State of the Map 2020 - Online (originally planned in Cape Town, South Africa) July 4-6, 2020