Chaos Computer Club - archive feed

Serverlandschaften sind ständigen Änderungen unterworfen. Umso wichtiger ist die Verwendung von Configuration-Managment-Tools zur Strukturierung der eigenen Infrastruktur. In Zeiten der Public, Hybrid oder sogar Multi Cloud-Umgebungen kann dies jedoch rasch zu einem ganzen ‚Zoo‘ an plattformspezifischen Management-Tools führen. Diese müssen einzeln gepflegt und gewartet werden, eine aufwändige und unübersichtliche Arbeit. Eine zentrale, plattformunabhängige Verwaltung des eigenen Rechenzentrums kann hier viel Arbeit und Zeit einsparen. Dieser Vortrag zeigt, wie Terraform genau in so einem Fall Abhilfe schaffen kann. Im Rahmen diese Vortrags wird eine kurze Einführung in Terraform gegeben, sowie am Beispiel zweier grundlegender Setups das Multi Cloud Prinzip demonstriert.

Serverlandschaften sind ständigen Änderungen unterworfen. Umso wichtiger ist die Verwendung von Configuration-Managment-Tools zur Strukturierung der eigenen Infrastruktur. In Zeiten der Public, Hybrid oder sogar Multi Cloud-Umgebungen kann dies jedoch rasch zu einem ganzen ‚Zoo‘ an plattformspezifischen Management-Tools führen. Diese müssen einzeln gepflegt und gewartet werden, eine aufwändige und unübersichtliche Arbeit. Eine zentrale, plattformunabhängige Verwaltung des eigenen Rechenzentrums kann hier viel Arbeit und Zeit einsparen. Dieser Vortrag zeigt, wie Terraform genau in so einem Fall Abhilfe schaffen kann.

Terraform ist ein plattformunabhängiges Open Source Tool zur Konfiguration und fortlaufendem Management der eigenen Infrastruktur. Mit Hilfe von Terraform lassen sich Änderungen an der Infrastruktur planen, reviewen und ausrollen. Terraform folgt dabei dem „infrastucture as code (IaC)“ Prinzip, d.h. Infrastrukturspezifikationen werden in entsprechenden Konfigurationsdateien hinterlegt. Dies erlaubt die Verwendung von Versionskontrolle und CI/CD Tools zum automatischen Deployment von Setups. Terraform bietet an dieser Stelle eine Vielzahl an verfügbaren Providern für einzelnen Service- und Clouddienste an und erleichtert somit die Benutzung im Zusammenhang von Multi Cloud Umgebungen.

Im Rahmen diese Vortrags wird eine kurze Einführung in Terraform gegeben, sowie am Beispiel zweier grundlegender Setups das Multi Cloud Prinzip demonstriert.

about this event: https://programm.froscon.org/2022/events/2765.html

Vortrag über den neuen MySQL Operator für den Betrieb von MySQL in Kubernetes Umgebungen (mit Demo).

Kubernetes ist eine standardisierte Umgebung für die Verwaltung von Arbeitslasten auf verschiedenen Maschinen, die sowohl für die Bereitstellung vor Ort als auch von allen großen Cloud-Anbietern unterstützt wird. Kubernetes funktioniert durch die Bereitstellung von containerisierten Arbeitslasten, indem deklarative Beschreibungen des geforderten Zustands bereitgestellt werden.

Ursprünglich war Kubernetes auf einfache zustandslose Microservices ausgerichtet, hat sich aber schnell auf andere Workloads ausgeweitet und kann daher für eine breite Palette von Lösungen verwendet werden. Einige Dienste, wie z. B. Datenbanken, benötigen jedoch eine besondere Behandlung. Für den Umgang mit dieser Art von Diensten kann Kubernetes mit Operatoren erweitert werden, die eine spezielle Art von Dienst an die Kubernetes-Plattform binden.

Mit der jüngsten Veröffentlichung von MySQL 8.0.29 wurde der neue MySQL Operator für Kubernetes veröffentlicht.

Der MySQL Operator für Kubernetes unterstützt den Lebenszyklus eines MySQL InnoDB Clusters innerhalb eines Kubernetes Clusters. Dies reicht von der Vereinfachung der Bereitstellung von MySQL-Server- und MySQL-Router-Instanzen, einschließlich der Verwaltung von TLS-Zertifikaten und der Einrichtung der Replikation, über die laufende Verwaltung dieser Instanzen bis hin zur Unterstützung von Backups, sei es einmalig oder nach einem Zeitplan. Beim Deployment läuft der MySQL Operator innerhalb des Kubernetes-Clusters und achtet auf Änderungen des gewünschten Zustands.

about this event: https://programm.froscon.org/2022/events/2762.html

Data minimization, data economy and transparency are mandatory for getting GDPR conform. This talk is a discussion, what you could do on your database to increase your privacy level.

Getting GDPR conform still is an issue for lots of developers. How you can implement some GDPR rules directly in your database? What kind of extra. columns does your SQL database need? How to control your SQL data? How to solve some transparency rules in your database? The talk just will discuss ideas how you could solve some mandatory GDPR specification directly in your SQL database.

about this event: https://programm.froscon.org/2022/events/2739.html

Geo-literacy provides skills to read, interpret and use geospatial information, where little evidence exists regarding the potential and capacity of new education programs in advancing these skills. We present a citizen science project held in 13 high schools in Israel, where the students practice participatory mapping with OpenStreetMap to map features relevant to the navigation of visually impaired pedestrians. We show that students improve their geospatial thinking and reasoning skills, including their self-esteem. We believe that this research contributes to various pedagogic and education levels, in terms of theoretical knowledge about the integration of innovative geo-literacy programs.

The 21st Century dictates that people have a good spatial and geographic understanding and knowledge. Geo-literacy is aimed to provide skills to read, interpret and use geospatial information. This is achieved by acquiring critical spatial thinking, reasoning, and analysis, and presenting understanding of the world using geographical terms and spatial language. Recent years have led to the development of new geo-literacy education programs specifically designed to nurture and promote these skills. These education programs build on geographical education that promotes spatial thinking and active citizenship. Still, little evidence exists regarding the potential and capacity of these programs in advancing civic and geographic skills and knowledge in the 21st Century, and on its contribution to - and advancing of - the individual and the society.

The aim of this research is to gain a better understanding of the development of geo-literacy in the framework of a citizen science project in high schools. The citizen science project implemented in several schools in Israel – landmarks for accessible space, advances scientific research that aims to make the urban environment more accessible for visually impaired pedestrians. The participating high school students practice participatory mapping with OpenStreetMap (OSM) to map features relevant to the navigation of visually impaired pedestrians. These map features are used for the automatic calculation of optimal walking routes. The project combines social involvement, learning through geographic information systems, and familiarity with the field of urban accessibility for visually impaired people. The project includes the following stage:

1. Pre-stage that includes a) the design of the modular learning environment, b) the organizational and pedagogical preparation of the project integration in schools, and c) questionnaires examining the current level of geographic literacy of the participating students and their perspective regarding the integration of citizen science in schools.

2. Intervention program that includes guest seminars (including YouTube videos), lectures and learning activities, exposure to the world of visually impaired people, and the need for accessible environments and learning activities in the field of geoinformation with emphasis on OSM, crowdsourcing, and participatory mapping.

3. Mapping missing data into OSM. This stage is carried out in the field with a designated app developed for this project. The app - “Mundi” - allows the mapping of specific geographic features (mapping elements) used for the calculation of accessible routes designed specifically for visually impaired pedestrians. The features include, among others, sidewalks, crossings, accessibility aids, and handrails. The app includes gamification and tasks to encourage the students to map the missing features in their area of residence.

4. Post-stage questionnaires aimed to investigate and analyze the development of spatial skills in the context of participation in this program, examining whether students’ level of geographic literacy improved and whether they gained new knowledge on urban accessibility and the navigation proficiencies of visually impaired pedestrians. This stage also included a quantitative analysis of the students’ contributions in terms of OSM mapping, among others, the number of map edits, type of mapped features, the spatial coverage and temporal extent of their mapping activity.

The study was conducted in the last two years in 13 high schools, including 25 classes and 460 students. The intervention model was implemented for three months in each class. The participating students implemented this project within their Cyber Geography studies, enabling them to learn through various geographic information systems. In total, close to 10,000 OSM edits were made by the students, which included more than 3,000 new crossings (and attributed tags), 400 new sidewalks, and 7,000 new street objects and obstacles (e.g., bus stations, light poles, trees, gates, bicycle parking).

Preliminary analysis showed that participation in the citizen science project increased the students’ geospatial thinking and reasoning. For example, according to the questionnaire variables, on a score scale of 0-100, the geospatial thinking score has increased from 31 to 56, while the spatial awareness score has increased from 34 to 73 (p < .001). The geographic skills knowledge has increased from 3 to 3.9 (scale of 1-5). Moreover, the students' self-esteem with respect to their knowledge and use of geographic skills has improved considerably. In addition, results show that the broad and in-depth intervention model increased the students' appreciation of the scientists' contribution to the project, the contribution of the program in general, and the satisfaction with their participation in the project.

This is the first project to introduce the use of OSM-based learning to the study of geography in Israel. Based on its outcome and analysis, we believe that this research contributes to various pedagogic and education levels, in terms of theoretical knowledge about the integration of innovative geo-literacy programs. These promote the drawing of operational and applicable actions regarding the planning of future projects and serving stakeholders in academia and the education system in terms of integrating scientific projects that increase students’ involvement in science and society and promote geo-literacy.

about this event: https://2022.stateofthemap.org/sessions/3YQRDX/

Follow the OSM journey of the Médecins Sans Frontières (MSF) from a mapathon in Berlin in 2014 to creating and contributing geodata for numerous MSF operations through the Missing Maps project. This talk will be about how MSF uses OpenStreetMap internally and how we contribute through remote and field mapping. We will also share the lessons learned and reflect on the biggest challenges for MSF in creating and using the OSM data.

The OpenStreetMap journey of Médecins Sans Frontières (MSF) started in 2014 with a mapping party in Berlin and field mapping in Lubumbashi. Eight years later, OpenStreetMap is the reference geographical dataset for most of MSF operations on the ground.

OpenStreetMap has been used in public health interventions, disease outbreaks, mortality studies and to support large logistical operations. Still every day we are learning how geographical information can support us in doing our job better, in reaching more people, in saving more lives.

MSF is not only using OpenStreetMap, but it also actively contributes to the map through the Missing Maps project launched in 2014 together with the American Red Cross, the British Red Cross, and the Humanitarian OpenStreetMap Team. Since then, MSF has trained dozens of Missing Maps champions, co-organized hundreds mapathons and involved thousands of volunteers in some 30 countries.

In this presentation we will talk about how MSF uses OpenStreetMap internally and how we contribute through remote and field mapping. We will also share the lessons learned and reflect on the biggest challenges for MSF in creating and using the OSM data.

about this event: https://2022.stateofthemap.org/sessions/XJZBFH/

The YouthMappers experience lends itself to explore interesting questions about the cultural and organizational aspects of data production and usage practices in OpenStreetMap, in order to improve them. First, this study aims to identify what are some of the qualitative and quantitative characteristics distinguishing the performance of YouthMappers as an academic-based community within OSM. Second, this study aims to better understand how the design approach taken by and on behalf of YouthMappers reinforces an identity as unique contributors.

Increasingly ubiquitous open spatial technologies offer the opportunity for new actors to participate in creating knowledge about the places where they live and work, and where they connect to others around the world. University students are one set of actors who have grown significantly in their visibility and contributions to OpenStreetMap, in part through the establishment of YouthMappers in 2015. This inclusive international network of university-based, youth-led, faculty-mentored chapters on more than 320 campuses in 66+ countries works to mobilize and support university student mapping action that responds to humanitarian and development needs by creating and using an ecosystem of data and tools centered on OpenStreetMap.

The YouthMappers experience lends itself to explore interesting questions about the cultural and organizational aspects of data production and usage practices in OpenStreetMap, in order to improve them. In this case, we explore these aspects as they occur within and through the academic sector, particularly through the hands and eyes of student youth. As a consortium design, this networked set of local groups works on the one hand, to create and use data on their local campuses and home communities, and on the other, to remotely contribute data on imagery-visible features in response to humanitarian, development, and knowledge needs wherever they may occur around the globe. Furthermore, they act not only within the OSM “community of communities” framework (Solís 2016), but also within an existing global infrastructure of academic institutions with its own set of shared educational aims, knowledge generating practices, and cultural norms. Meanwhile, students are motivated both by learning and using new skills and workforce competencies as well as by the opportunity to participate in the world’s largest volunteered geographic information project and the activities that make common good use of the data. So how do YouthMappers navigate these different aims within these different spaces of action?

To address this question, two aspects of this experience are the focus of attention in this study. First, this study aims to identify what are some of the qualitative and quantitative characteristics distinguishing the performance of YouthMappers as an academic-based community within OSM. Second, this study aims to better understand how the design approach taken by and on behalf of YouthMappers reinforces an identity as unique contributors.

The presentation first will provide a description and justification for the purposeful design of the YouthMappers consortium (Solís et al. 2018) within the context of OpenStreetMap (Brovelli et al. 2019). The study will be contextualized with a review of literature on the current state of higher education, particularly with respect to a present tension around higher ed institutions’ purpose as sites for both workforce preparation and global citizenship. The latter point will be situated with reference to scholarship on the global targets of the Sustainable Development Goals (SDGs), as perhaps the predominant discourse for international action across humanitarian domains. This review sets up three interlocking hypotheses that the evidence is anticipated to reject:

H1: (Action-of-Performance) Participating youth either map only locally or remotely, but not both;

H2: (Hybrid-Roles) Participating youth cannot simultaneously pursue personal aims to prepare themselves for the workforce and to express their identities as global citizens; and

H3: (Movement-Minded) Participating youth cannot articulate the impacts/benefits of actions undertaken for broader communities or society through their work with OSM, nor identify the roles/contributions of youth action in this work for the common good.

Data to test the first hypothesis relate to performance and include a range of metrics of participation (Andal et al. 2022; Boateng et al. 2022; Walachosky et al., 2022); statistics of known users (Anderson 2022), and a review of data from other studies of YouthMappers’ editing contributions (e.g., Mahmud et al. 2022). Data to test the second hypotheses relate to identity and come from the long-running student-authored blogs (Hite et al., 2018), as well as a global survey of YouthMappers collected in 2019 accompanied by a qualitative set of member queries to iterate interpretation of the survey results (Solís, Anderson & Rajagopalan 2020; Solís et al. 2022). Data to test the third hypotheses come from a set of case studies that are considered with respect to the SDGs (Solís & Zeballos, forthcoming). Collectively, these data are analyzed with respect to the above hypotheses.

Results reveal a spectrum of interests balancing local and global mapping across the consortium, and across regions, and other axis of participation. They also indicate the extent to which youth reflect on local benefits, including personal skill development, versus global citizenship, including how they understand the meanings of their actions for SDGs, locally and globally. Detected differences by gender, world region, and duration of participation are interpreted and validated with additional qualitative data. The results are presented with respect to rejecting all three hypotheses, which validate the model.

These findings help to begin to build a case for understanding the potential of the YouthMappers design to advance the goals of OSM, of the academic community, and potentially the SDGs. In particular, we discuss the possible role of university systems as third space sites for enabling performance and identities for youth action (Bawakyillenuo et al., 2013; Soja, 1996). This gives consideration to the possibility for universities to serve as sites that Heaney and Rojas (2014) characterize as hybrid organizations that, when linked to global discourses on issues like sustainability (SDGs) and open data (OSM), can mobilize youth to create and participate in what we term digital humanitarian “hybrid movements” (Solís, et al. 2022). In turn, this hybrid movement puts into place both a framework of performance and a space of identity which can serve to advance OSM communities.

These findings offer insights for how other types of communities could leverage their existing milieu in ways that strengthens OSM broadly. Ultimately, the idea of hybrid movements encourages OSM to embrace a pluralistic, inclusive and diverse set of communities that not only bring individual contributions but leverages other systems like the landscape of academia was systematically enlisted via the YouthMappers design.

about this event: https://2022.stateofthemap.org/sessions/THYCMA/

OpenIndoor is an open source SaaS that uses OpenStreetMap indoor data to display a 3D graphical rendering of building interiors. The resulting map offers a gamified experience to meet different types of needs: indoor navigation, data representation, immersive tour etc.

We will discuss how we use the available open data and the Maplibre engine to address these different use cases.

about this event: https://2022.stateofthemap.org/sessions/HEKRDY/

This talk explores the effects of OpenStreetMapping on the mappers. These effects also infer that OSM mapping can be used as a tool for skill-building.

OpenStreetMap, the crowdsourced geospatial database, currently has over eight million registered members [1]. This makes it one of the largest VGI projects with proven multifaceted use cases e.g. post-disaster response, combating female genital mutilation, app development, and navigation. The database is wholly made and maintained by its contributors, making all decisions without a top-down governing authority. People in OSM contribute in multiple ways, extending databases, onboarding newcomers, building community, exchanging information, and providing public benefit. Within the OSM community, OSM mapping is regarded as a form of volunteering to create freely accessible geodata. However, recent studies suggest that the experience a mapper gains through the mapping process could be equally important as well [2-4]. Building on the existing body of knowledge, in this talk, we will share the findings our research on how mapping in OSM affects the mapper.

Being a quality OSM mapper requires training and practice. The act of OSM mapping requires transitioning from having an interest in mapping to creating an OSM account, learning how to use the application, developing an understanding of the technical and theoretical dimensions of mapping, and then applying these skills and knowledge to accurately convert satellite imagery into map data. Such a process engages mappers in multiple decision-making processes and continuously exposes them to buildings, topographies, and features of satellite imagery. We suggest that such experiences affect the mapper in multiple ways.

We studied a youth mapping internship called Digital Internship and Leadership (DIAL) Program conducted in three cohorts. We chose this internship program for its inclusiveness in terms of academia, gender, and the geographical locations that the participants came from. Participant mappers were called through an open invitation on social media. Recent high school graduates and undergraduate students participated in the mapping internship. They were from diverse academic backgrounds (geomatics engineering, architecture, crisis management, management, forestry, geomatics engineering, computer science and engineering, electronics engineering, management, public health, mechanical engineering). The internship aimed to reduce OSM data gaps in rural Nepal through the involvement of Nepali high school graduates. The program was designed and executed by Kathmandu Living Labs (KLL). We studied the self-assessed experiences of the participant mappers at two different points of time: (i) during the mapping program (ii) after two years for Cohorts II and III, and three years for Cohort I. Short-term effects were studied through grounded theory coding of reports and blogs documented during the internship period. For long-term impacts, an online survey administered to identify if the effects persisted.

Results show OSM mapping helps the mappers develop a number of vital skill sets and expand their knowledge in a variety of areas. Some of them are: deepening of civic engagement, development of social identity, expansion of geographic knowledge, spatial awareness, increase in happiness and satisfaction. They retain most of these skills even in the long run, irrespective of differences in gender, academic, or professional backgrounds. Surprisingly, 44.8% of the participants cited ‌they considered being a professional mapper or cartographer at some point in time because of their experience in DIAL. The same people report that OSM mapping increased their belief in their ability to help society.

Apart from these individual benefits, we also sense collective benefits. Collective benefits such as network development and an increased sense of civic responsibility hold potential to facilitate broader public good. These might also be applicable for youth mobilization, team building, and collective work.

It is difficult to pinpoint the exact root cause of this development, however, the benefits of OSM mapping may be in part related to the continuous exposure to satellite imagery, continuous use of technology, the requirement of multiple layers of decision-making, humanitarian aspects of OSM, and the growing global OSM community encouraging conversations around it.

Our findings build upon the studies of the use of OSM in high schools, which was noted to increase creativity and spatial awareness among the students [5, 3, 2]. When compared to Minghini et al.’s (2016) study with ten-year-olds, the similarity in findings suggests ‌these developments might be similar across ages. These developments suggest new directions toward the use of OSM as a tool for youth skill building and youth community engagement and design newer incentive mechanisms for people to join and retain in OSM.

There is still a huge scope of investigation left in this area, ideally through a longitudinal study with a bigger and more diverse sample and comparisons between different program designs, to fully understand the wide array of effects of OSM mapping on the mappers, as well as the potential to deepen positive outcomes via associated youth learning and leadership programs. There are undoubtedly other categories of benefits of OSM mapping that are yet to be identified. Hence, it is worthwhile to reconsider the idea of participatory mapping and related programs, and their effects on the contributing mappers.

about this event: https://2022.stateofthemap.org/sessions/HSSWBD/

OpenStreetMap data represents a valuable source of information for public green areas in large urban centers and effectively measures the United Nations' Sustainable Development Goal 11.7. Our study provides a threefold contribution in this direction. First, we validate land-use-related tags in OpenStreetMap, through a comparison with satellite data from the European Urban Atlas. We then propose a framework and an interactive tool to measure access to public green areas through several established indices. Finally, we show how the framework can be used to simulate the impact of new green areas and help policymakers design effective interventions.

As of 2020, around 55% of the worldwide population lives in urban areas and the World Bank estimates forecast an increase of around 1.5 times in the urban population by 2045. Cities are also major contributors to the climate-change, with a consumption of about 78% of the worldwide energy and a production of 60% of greenhouse gas emissions. A transition toward greener cities is often called as one of the solutions to reduce the environmental impact of cities, but also to make the urban environments more liveable, with positive spillovers on the mental and physical health of their population. In this context, the United Nations' Sustainable Development Goals 11.7 [1] indicates the need to make cities more inclusive and safe, but also environmentally sustainable, calling for the universal provision of safe, inclusive, and accessible, green and public spaces. A proper evaluation of this target requires complementing standard average metrics, looking for instance at the surface of green areas per capita within an urban area, with more sophisticated metrics, that are able to capture the interplay between the spatial distribution of both the population and green areas within a city.

A few studies on selected cities worldwide highlighted the importance of considering this interplay [2-7].

A recent study on the city of Seoul [3] shows that vast portions of the parks in the city are located in outer areas so that frequent opportunities to visit them are relatively minimal. In general, urban green areas in Seoul are inadequately distributed in relation to population, land use, and development density. By contrast, in the case of Shanghai [6], the degree of accessibility to green areas appears to decrease as we move from the city core to the urban periphery. The authors also found a negative association between the degree of accessibility to green areas and the housing prices, which translates directly into a large environmental inequality, wherein wealthier communities benefit more from green space accessibility than disadvantaged communities. A similar socio-economic, but also ethnic, stratification is observed in the city of Chicago, where white-majority census tracts generally enjoy a significantly higher degree of accessibility to green areas than minority-dominated census tracts [7]. The former ethnic group also presents a lower income-based green-areas accessibility inequity compared to the other racial-ethnic groups.

Efforts to move beyond case studies and provide more accurate cross-country indicators have led to the construction of the 'generalised potential access to green areas’ from the European Commission, which is provided as one of the city-level indicators of the Global Human Settlement - Urban Centers Database [8]. The metric measures the proportion of the urban population for urban centers included in the atlas living in high green areas. Based on satellite data on the Normalized Difference Vegetation Index, the metric is however agnostic with respect to the characteristics of these high green areas - for instance, whether these are public or private green areas - and any accessibility notion, since the metric does not consider that people can move from their residential location. These limitations are accounted for in a recent study for the European Environmental Agency [9], whose geographical coverage is however limited to specific urban hotspots in Europe, for which high-resolution land use data from the Urban Atlas (https://land.copernicus.eu/local/urban-atlas) is available.

With its worldwide coverage and detailed mapping, the use of land use and street network data from OpenStreetMap [10] allows to expand the analysis beyond the European boundary. Our study provides a threefold contribution in this direction. First, we compare detailed high-resolution land use data on green uses for European hotspots included in the Urban Atlas with land use-related tags in OpenStreetMap for similar geographical areas. We use similarity indices to assess the degree of completeness of the OSM tags of natural land uses in urban environments and show how the quality varies according to the type of natural use and the size as well as the geographical area of the urban center under consideration. Second, we propose a framework for the monitoring of the target for large urban centers worldwide. In particular, by leveraging data from OpenStreetMap and population estimates from the Global Human Settlement [11], we develop a framework to measure accessibility to public green in large urban centers worldwide at a high resolution. For each urban center, we identify natural green areas using OSM tags on ‘land use’, ’natural’ and ‘leisure’ (e.g.: ‘leisure’:’park’) and extract the walkable street network to measure walking distances. Accessibility indices are then constructed for each populated cell of the population grid. The framework is also used to build an interactive tool to navigate our results, which can be customized to select the type of green of interest, as well as the size of the green area. Following the academic literature on urban accessibility, we build several accessibility indices, from a minimum distance index to exposure metrics. The resulting database represents a valuable source of information for policymakers to identify cities that are missing out and direct attention to those subareas within otherwise well-performing cities where the degree of accessibility is still insufficient. The constructed indices are then used to study the relationship between the measured level of accessibility and the structural characteristics of the cities and unveil the role of small green areas as accessibility enhancers, particularly in densely inhabited urban centers. Thirdly, we show how the framework can be used to simulate the impact of different urban interventions, from the addition of a new public green area to infrastructural interventions to the street network, to help policymakers to shape transitions toward more sustainable and accessible urban environments.

about this event: https://2022.stateofthemap.org/sessions/TA9VAF/

Cities worldwide encourage urban active mobility by advocating policy and planning. Although contribution is evident, in practice, these actions disregard population parts that have mobility impairments. This research suggests using OpenStreetMap data in customized analytical models to assess the accessibility level of the urban environment for visually impaired pedestrians. Models results show the existence and spatial distribution of existing accessibility problems, including challenging street network connectivity and dangerous walking areas. These models can be used to enable decision makers, city stakeholders and practitioners to enrich management, monitoring and development of their cities, and support sustainable, livable lifestyles and walkability equality.

Many efforts that include city policy and planning strategies are implemented to encourage urban active mobility. The outcome of these actions is measured by how transportable and accessible the city is. Although contribution is evident, in practice, the commonly used measures mostly disregard a huge part of the population that have mobility impairments, which require specific accessibility needs, preventing them to be an equal part of the sustainable city vision.

This research suggests using OpenStreetMap (OSM) data in customized analytical models to assess the accessibility level of the urban environment for visually impaired pedestrians. In principle, the models analyze the city on two levels: routing and accessibility. These are evaluated, correspondingly, based on possible routes, e.g., how long the optimal route is for visually impaired pedestrians compared to the shortest one, and on area, e.g., what is the overall accessibility and safety of a predefined urban extent. The play of both measures enables us to quantify the level of mobility and accessibility of the analyzed city. To do so, we implement the following steps:

1. We examine the navigation preferences of visually impaired pedestrians in the urban space. This allows a better understanding of the various environmental and morphological factors and characteristics of the urban form that promote safe and accessible navigation. These are translated into spatial and temporal criterion: a) Way Type, which quantifies how suitable the path is in terms of usage and safety; b) the existence of Vision Impairment Assistive Landmarks that support safe wayfinding and navigation; c) Way Complexity, which measures the level of linearity of the path; and d) Crowdedness, which measures the overall pedestrian traffic volume.

2. We transform OSM’s street network into a weighted graph, where for each graph edge we calculate the cost according to the above criteria. Cost is derived from segments that facilitate safe and accessible walking for visually impaired pedestrians (e.g., separated sidewalks and straight paths), and segments that hinder safe and accessible walking for visually impaired pedestrians (e.g., shared and overcrowded streets).

3. We develop three analytical models that measure the accessibility level of the urban environment for visually impaired pedestrians: a) street-based, which relies on averaging the costs of all graph edges for a given area, hence it can be implemented for different urban levels (spatial extents); b) centrality-based, which adds on the street-based the centrality indices betweenness and closeness that consider the significance of each graph edge in the street network in respect to all other edges (high centrality values mostly signify streets that attract large pedestrian traffic flow); c) route-based, a navigational method, in which numerous routes are generated on the graph for location tuples, and then the weight ratio of the optimal route for visually impaired pedestrians and the shortest route (commonly used for seeing pedestrians) is evaluated. The smaller the weight value, the more accessible the route.

The developed models are evaluated for Greater London, the UK. 33 boroughs with their wards are analyzed, resulting in processing 421,107 streets, 377,164 OSM nodes and 634, 871 OSM ways. Results show the existence and spatial distribution of accessibility problems for visually impaired pedestrians. The street-based model highlights the fact that urban nature and green spaces, which are typically considered as contributing to wellbeing and encourage walking, are less accessible for visually impaired people, mostly due to the existing road types, e.g., gravel and dirt roads or shared spaces (bikes and pedestrians that share the same path), which are less accessible for this population. The centrality-based model shows that central streets are mostly more accessible, meaning that borough centers are considered in general as accessible, but as distance from city centers grows, the urban environment becomes less accessible. The route-based model, where more than 1,500,000 routes (with length shorter than 1,000 meters) were calculated, showed that on average the optimized routes are 11% longer and 17.5% more accessible than the shortest ones. Some optimal walking routes are twice as long as the shortest ones, where some impose safety issues that critically endanger visually impaired pedestrians. Wards that have a large proportion of street segments with poor accessibility evenly distributed throughout the ward tend to show less efficient route planning in terms of optimal routes that are considerably longer. In general, the route-based model produces clearer results to understanding the city’s morphology in terms of accessibility for visually impaired pedestrians.

To a large extent, these models depend on the quality of OSM data, such that feature completeness and tag correctness should be investigated. In terms of completeness, we found that sidewalks and crossings, which are two important model features, are not always mapped in OSM, mostly in the outskirts of London. One solution is to use learning methods and prediction models to complete missing data. In terms of tag correctness, we found that some inconsistencies exist with certain tags. One solution can be to make tag definitions in, e.g., OSM Wiki, more inclusive and clear, with a focus on accessibility aspects.

Results show how various accessibility levels for visually impaired pedestrians might be assessed and where they are found in the city, pointing to the existing problems this community faces today when navigating. These include challenging street network connectivity and dangerous walking areas. The results also demonstrate that the current practice of urban planning and design worldwide still suffers from lack of democratization, limiting the mobility and navigation of certain groups. The accessibility models developed in this research can be used for better city planning and design, enhancing the city mobility and walkability equality and improving quality of life for these vulnerable road users. Our findings provide analytical tools to enable decision makers, city stakeholders and practitioners to enrich management, monitoring and development of their cities, and support sustainable, livable lifestyles and walkability equality. These, in turn, will ease navigation and mobility of visually impaired pedestrians, overall improving health outcomes and their integration into society.

about this event: https://2022.stateofthemap.org/sessions/MXS9R8/