99 research outputs found

    Towards an Automated Comparison of OpenStreetMap with Authoritative Road Datasets

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    OpenStreetMap (OSM) is an extraordinarily large and diverse spatial database of the world. Road networks are amongst the most frequently occurring spatial content within the OSM database. These road network representations are usable in many applications. However the quality of these representations can vary between locations. Comparing OSM road networks with authoritative road datasets for a given area or region is an important task in assessing OSM’s fitness for use for applications like routing and navigation. Such comparisons can be technically challenging and no software implementation exists which facilitates them easily and automatically. In this article we develop and propose a flexible methodology for comparing the geometry of OSM road network data with other road datasets. Quantitative measures for the completeness and spatial accuracy of OSM are computed, including the compatibility of OSM road data with other map databases. Our methodology provides users with significant flexibility in how they can adjust the parameterization to suit their needs. This software implementation is exclusively built on open source software and a significant degree of automation is provided for these comparisons. This software can subsequently be extended and adapted for comparison between OSM and other external road datasets

    Mapping and the Citizen Sensor

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    Maps are a fundamental resource in a diverse array of applications ranging from everyday activities, such as route planning through the legal demarcation of space to scientific studies, such as those seeking to understand biodiversity and inform the design of nature reserves for species conservation. For a map to have value, it should provide an accurate and timely representation of the phenomenon depicted and this can be a challenge in a dynamic world. Fortunately, mapping activities have benefitted greatly from recent advances in geoinformation technologies. Satellite remote sensing, for example, now offers unparalleled data acquisition and authoritative mapping agencies have developed systems for the routine production of maps in accordance with strict standards. Until recently, much mapping activity was in the exclusive realm of authoritative agencies but technological development has also allowed the rise of the amateur mapping community. The proliferation of inexpensive and highly mobile and location aware devices together with Web 2.0 technology have fostered the emergence of the citizen as a source of data. Mapping presently benefits from vast amounts of spatial data as well as people able to provide observations of geographic phenomena, which can inform map production, revision and evaluation. The great potential of these developments is, however, often limited by concerns. The latter span issues from the nature of the citizens through the way data are collected and shared to the quality and trustworthiness of the data. This book reports on some of the key issues connected with the use of citizen sensors in mapping. It arises from a European Co-operation in Science and Technology (COST) Action, which explored issues linked to topics ranging from citizen motivation, data acquisition, data quality and the use of citizen derived data in the production of maps that rival, and sometimes surpass, maps arising from authoritative agencies

    European Handbook of Crowdsourced Geographic Information

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    This book focuses on the study of the remarkable new source of geographic information that has become available in the form of user-generated content accessible over the Internet through mobile and Web applications. The exploitation, integration and application of these sources, termed volunteered geographic information (VGI) or crowdsourced geographic information (CGI), offer scientists an unprecedented opportunity to conduct research on a variety of topics at multiple scales and for diversified objectives. The Handbook is organized in five parts, addressing the fundamental questions: What motivates citizens to provide such information in the public domain, and what factors govern/predict its validity?What methods might be used to validate such information? Can VGI be framed within the larger domain of sensor networks, in which inert and static sensors are replaced or combined by intelligent and mobile humans equipped with sensing devices? What limitations are imposed on VGI by differential access to broadband Internet, mobile phones, and other communication technologies, and by concerns over privacy? How do VGI and crowdsourcing enable innovation applications to benefit human society? Chapters examine how crowdsourcing techniques and methods, and the VGI phenomenon, have motivated a multidisciplinary research community to identify both fields of applications and quality criteria depending on the use of VGI. Besides harvesting tools and storage of these data, research has paid remarkable attention to these information resources, in an age when information and participation is one of the most important drivers of development. The collection opens questions and points to new research directions in addition to the findings that each of the authors demonstrates. Despite rapid progress in VGI research, this Handbook also shows that there are technical, social, political and methodological challenges that require further studies and research

    Spatial and Temporal Sentiment Analysis of Twitter data

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    The public have used Twitter world wide for expressing opinions. This study focuses on spatio-temporal variation of georeferenced Tweets’ sentiment polarity, with a view to understanding how opinions evolve on Twitter over space and time and across communities of users. More specifically, the question this study tested is whether sentiment polarity on Twitter exhibits specific time-location patterns. The aim of the study is to investigate the spatial and temporal distribution of georeferenced Twitter sentiment polarity within the area of 1 km buffer around the Curtin Bentley campus boundary in Perth, Western Australia. Tweets posted in campus were assigned into six spatial zones and four time zones. A sentiment analysis was then conducted for each zone using the sentiment analyser tool in the Starlight Visual Information System software. The Feature Manipulation Engine was employed to convert non-spatial files into spatial and temporal feature class. The spatial and temporal distribution of Twitter sentiment polarity patterns over space and time was mapped using Geographic Information Systems (GIS). Some interesting results were identified. For example, the highest percentage of positive Tweets occurred in the social science area, while science and engineering and dormitory areas had the highest percentage of negative postings. The number of negative Tweets increases in the library and science and engineering areas as the end of the semester approaches, reaching a peak around an exam period, while the percentage of negative Tweets drops at the end of the semester in the entertainment and sport and dormitory area. This study will provide some insights into understanding students and staff ’s sentiment variation on Twitter, which could be useful for university teaching and learning management

    Analyzing the Tagging Quality of the Spanish OpenStreetMap

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    In this paper, a framework for the assessment of the quality of OpenStreetMap is presented, comprising a batch of methods to analyze the quality of entity tagging. The approach uses Taginfo as a reference base and analyses quality measures such as completeness, compliance, consistence, granularity, richness and trust . The framework has been used to analyze the quality of OpenStreetMap in Spain, comparing the main cities of Spain. Also a comparison between Spain and some major European cities has been carried out. Additionally, a Web tool has been also developed in order to facilitate the same kind of analysis in any area of the world

    European Handbook of Crowdsourced Geographic Information

    Get PDF
    "This book focuses on the study of the remarkable new source of geographic information that has become available in the form of user-generated content accessible over the Internet through mobile and Web applications. The exploitation, integration and application of these sources, termed volunteered geographic information (VGI) or crowdsourced geographic information (CGI), offer scientists an unprecedented opportunity to conduct research on a variety of topics at multiple scales and for diversified objectives. The Handbook is organized in five parts, addressing the fundamental questions: What motivates citizens to provide such information in the public domain, and what factors govern/predict its validity?What methods might be used to validate such information? Can VGI be framed within the larger domain of sensor networks, in which inert and static sensors are replaced or combined by intelligent and mobile humans equipped with sensing devices? What limitations are imposed on VGI by differential access to broadband Internet, mobile phones, and other communication technologies, and by concerns over privacy? How do VGI and crowdsourcing enable innovation applications to benefit human society? Chapters examine how crowdsourcing techniques and methods, and the VGI phenomenon, have motivated a multidisciplinary research community to identify both fields of applications and quality criteria depending on the use of VGI. Besides harvesting tools and storage of these data, research has paid remarkable attention to these information resources, in an age when information and participation is one of the most important drivers of development. The collection opens questions and points to new research directions in addition to the findings that each of the authors demonstrates. Despite rapid progress in VGI research, this Handbook also shows that there are technical, social, political and methodological challenges that require further studies and research.

    Mobile Application for Noise Pollution Monitoring through Gamification Techniques

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    Full data coverage of urban environments is crucial to monitor the status of the area to detect, for instance, trends and detrimental environmental changes. Collecting observations related to environmental factors such as noise pollution in urban environments through classical approaches implies the deployment of Sensor Networks. The cost of deployment and maintenance of such infrastructure might be relatively high for local and regional governments. On the other hand recent mass-market mobile devices such as smartphones are full of sensors. For instance, it is possible to perform measurements of noise through its microphone. Therefore they become low-cost measuring devices that many citizens have in their pocket. In this paper we present an approach for gathering noise pollution data by using mobile applications. The applications are designed following gamification techniques to encourage users to participate using their personal smartphones. In this way the users are involved in taking and sharing noise pollution measurements in their cities that other stakeholders can use in their analysis and decision making processes

    Developing Android Mobile Map Application with standard navigation tools for pedestrians

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    Advanced features of modern mobile devices have made it possible to develop and use maps and map based applications for navigation purposes. Since most mobile map applications nowadays are developed for motor vehicles, there is a demand for portable pedestrian navigation applications. In this thesis the Android mobile map application with standard navigation tools for pedestrian navigation was developed, as a platform for facilitating the Lund Challenge location based demonstrator of the HaptiMap project. The pivotal aim of the Lund Challenge demonstrator is to make the sights of Lund city more accessible. The mobile phone application is being designed as a touristic, historical location based game which will also assist tourists to navigate themselves in the city. To enable exploration of historical and current sites of Lund the demonstrator should contain basic components of exploring and way finding. Prior to the development the OpenStreetMap (OSM) road network data and Swedish National Road Database (NVDB) were introduced. The main advantage of using the OSM data over the NVDB dataset is the completeness of the OSM data in terms of pedestrian paths. The datasets were imported to PostgreSQL spatially extended PostGIS database, where different routing algorithms provided by pgRouting were used for routing calculations. As the Lund Challenge demonstrator is intended not only for general users but also for visually impaired users, the problem of user navigation in the parks and open areas were also discussed and the feasibility study was performed. The limitation of the developed application was the problem of the user navigation in the parks and open areas. It is therefore necessary to upgrade the road database with possible path in the open areas and parks in order to implement this application.Advanced features of modern devices have made it possible to develop and use maps and map-based applications for navigation purposes. Since most mobile map applications are currently developed for motor vehicles, there is a demand for portable pedestrian navigation applications. In this thesis, a mobile map application was developed with standard navigation tools for pedestrians, which can be used with mobile phones running Android Operating System. The application will be used as a platform for facilitating the Lund Challenge location based demonstrator. Lund Challenge location based demonstrator is designed to make historical and actual maps of Lund more accessible and is a part of the HaptiMap project. This project aims to create maps and develop location-based services for all users, including elderly and visually impaired. The goal of the Lund Challenge location based demonstrator (also known as The Lund Time Machine) is to minimize the efforts of pedestrians, especially tourists, with finding interesting sites around the city. Initially, it is being designed as a historical location based game which will assist tourists to navigate themselves around the city. In order to further explore historical and current sites, the Lund Challenge should be enhanced with the basic features of exploration and navigation included in this thesis. The road network data was chosen from two available sources: 1) data from OpenStreetMap (OSM) project which provides free geographic data, and 2) The Swedish National Road Database (NVDB) authorized by the Swedish government, which includes all Swedish road network and selected cycle paths. For this thesis, analysis was performed on the datasets using different shortest path algorithms for routing calculations. A primary advantage of using OSM over NVDB is the completeness of data relating to pedestrian paths. As a result, the determination was made that the OSM option was more appropriate for the purpose of this thesis. Since the Lund Challenge location based demonstrator is intended for both general and visually impaired users, the problem of user navigation in parks and open areas was also discussed and a feasibility study was performed. This study revealed a limitation in the application with user navigation in parks and open areas. To resolve this, it is necessary to upgrade the road network with all possible pedestrian paths for parks and open areas
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