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Volunteered Geographic Information (VGI) such as data derived from the OpenStreetMap (OSM) project is a popular data source for freely available geographic data. There is frequently a cause of concern regarding the quality and usability of such data. In addition to our former studies (further here) or complementing our OSM in GIScience Book in a new study, the quality of OSM land use and land cover (LULC) data is investigated for an area in southern Germany in comparison to an authorative data set.
Two spatial data quality elements, thematic accuracy and completeness are addressed by comparing the OSM data with an authoritative German reference dataset. The results show that the kappa value indicates a substantial agreement between the OSM and the authoritative dataset. Nonetheless, for our study region, there are clear variations between the LULC classes. Forest covers a large area and shows both a high OSM completeness (97.6%) and correctness (95.1%). In contrast, farmland also covers a large area, but for this class OSM shows a low completeness value (45.9%) due to unmapped areas. Additionally, the results indicate that a high population density, as present in urbanized areas, seems to denote a higher strength of agreement between OSM and the DLM (Digital Landscape Model). However, a low population density does not necessarily imply a low strength of agreement.


Dorn H., Törnros T., Zipf A. (2015): Quality Evaluation of VGI Using Authoritative Data—A Comparison with Land Use Data in Southern Germany. ISPRS International Journal of Geo-Information. 2015; 4(3):1657-1671.

The 12th International Symposium on Location Based Services 2015 (LBS 2015) will take place this year in Augsburg (Germany), on Sept. 16-18, 2015.
Prof. Dr. Alexander Zipf is one of the invited keynote speakers and will give a talk about
“Enriching Location Based Services with VGI and Social Media”
on
Thursday, 17/Sep/2015 (1:45pm - 2:30pm).
Looking forward to meet you!

The Ministry of Science, Research and Arts, Baden-Wuerttemberg has funded a new research project called 4DEMON, which will approach the research front of 4D Near Real-Time Environmental Monitoring.

Our physical environment underlies permanent changes in space and time with strongly varying triggers, frequencies, magnitudes and also consequences to humans. Monitoring of Earth surface processes (e.g. landslides) and the assessment of environmental properties (e.g. agricultural plant conditions) is crucial to improve our scientific understanding of complex human-environmental interactions and helps us to respond by adaptation or mitigation.

The last decade has witnessed extensive application of 3D environmental monitoring with the LiDAR technology, also referred to as laser scanning. Although a multitude of automatic methods were developed to extract environmental parameters from LiDAR point clouds, only little research has focused on highly multitemporal LiDAR monitoring (4D-LiDAR). Large potential of applying 4D-LiDAR is given for landscape objects with high and varying rates of change (e.g. plant growth), and also for processes with sudden unpredictable changes (e.g. natural hazards).

In this project we (re)assess the scientific concepts and data models for big 4D LiDAR data. In our core concept, a single LiDAR point is treated as an observation in space and time, and the measurements are not independent of each other in space and time. Further, based on two real-world use cases we will develop new algorithms for surface parameter derivation (agricultural crops) and change detection (landslides) making use of the “full history” contained in the 4D point cloud time series. We will evaluate our novel methods with respect to near real-time analysis capability (in between of two epochs), making use of the entire big point cloud archive collected during permanent long-term terrestrial LiDAR monitoring.

The International Journal of Geographical Information Science (IJGIS) published a first review by Wen Lin at Taylor & Francis Online (DOI: 10.1080/13658816.2015.1077965) about our Springer book on
OpenStreetMap in GIScience: experiences, research and applications, edited by Jamal Jokar Arsanjani, Alexander Zipf, Peter Mooney and Marco Helbich (2015, Springer Series: Lecture Notes in Geoinformation and Cartography, 324 pp., ISBN 978-3-319-14279-1)

The book contains 16 chapters grouped into four different aspects of OpenStreetMap in GIScience including 1) Data Management and Quality, 2) Social Context, 3) Network Modeling and Routing, 4) Land Management and Urban Form along with a foreword from Muki Haklay (UCL).

The book starts with an overview and review article (*) by Jokar Arsanjani, J., Zipf, A., Mooney, P., Helbich, M., about An introduction to OpenStreetMap in GIScience: Experiences, Research, Applicationsp 1-15..

OSM in GIScience

Download Table of Contents PDF
The book on SpringerLink

(*) Jokar Arsanjani, J., Zipf, A., Mooney, P., Helbich, M., (2015): An introduction to OpenStreetMap in GIScience: Experiences, Research, Applications. In: Jokar Arsanjani, J., Zipf, A., Mooney, P., Helbich, M., (eds). OpenStreetMap in GIScience: experiences, research, applications. ISBN:978-3-319-14279-1, Springer Science. p. 1-15.

Once again the “Fachaustausch Geoinformation” will be organized by the Geo-Network of the Metropolitain Region Rhine-Neckar GeoNet.MRN” in Heidelberg on 11/25/2015.
The event serves the networking and exchange of experience between interested parties, experts, users and decision-makers from business, science, politics and government on applications and current issues of regional data and geographic information systems.

Morning program:

  • Keynote speeches and panel discussion on current topics (regional data for the infrastructure planning, Open Data, INSPIRE etc.)
  • Award Baden-Württemberg Challenge 2015 as part of the European Satellite Navigation Competition

Afternoon program with three parallel lecture and discussion sessions:

Session 1 “Virtual Building”
Session 2 “Energy and energy storage”
Session 3 “Microscale statistics for local and regional planning”

Do you want to present your institution? Please request the help of Mr Lukas Berkel (Lukas.Berkel@mrn.com). Like last year the members and friends of GeoNet.MRN will present the latest trends and products of the geo-business in an exhibition area.

The program will be finalized in early September and can then be found at the new portal www.geonet-mrn.de .
We would be pleased if we can welcome you at the Regional Conference 2015!

geonet.mrn

The TV science program “X:enius” on the German TV channel “Arte” broadcasts a program about “Navigation - How do we find the right way?” (in German).
Amongst others it features some of our work at GIScience Heidelberg on OpenStreetMap and crisis mapping, as well as Raul Krauthausen introducing the WheelMap project, which is partner in our joint EU project Cap4Access, where we develop wheelchair routing and navigation based on OpenRouteService.

The program will be transmitted on Arte TV on
Friday, 28. August at 7:15 am.
It is also available online in the Arte TV mediathek as video for some time. http://www.arte.tv/guide/de/051083-019/x-enius
Some parts of the video about our work had been transmitted earlier on ARD.

The Klaus Tschira Foundation (KTS) Heidelberg can look back to 20 successful years of history since its foundation in 1995 (www.20jahrekts.de). The foundation of the European Media Laboratory (EML) in 1997 also had a great impact on Geoinformatics in Heidelberg, with Alexander Zipf being the first PhD student there in the first EML research project “Deep Map”. Later this led also to the foundation of the spin-off company Heidelberg Mobil International.

KTS Heidelberg

We would like to inform about a new open source tool that allows matching of GPS trajectories to corresponding street segments. The tool implements a simplified version of the algorithm presented by Zhang et al. (2010). It is a JAVA based implementation and has been put under LGPL license. You can access the source code via our Github account.

The main steps of the algorithm are: (a) Select candidate tracks using a buffer (light green) around a street segment (dark green), (b) create profile lines (blue), (c) select GPS tracks (red) which intersect at least 70% of the profile lines and (d) clip GPS tracks at buffer.

The streets and GPS traces to be matched, need to be stored in a PostgreSQL/PostGIS database. For GPS trajectories collected in OSM project, osmgpxfilter (reported earlier) may be used to fill the database. The result is written into a new table, referencing the unique identifiers of the streets and the GPS trajectories. We have mainly used the tool to match OSM GPS trajectories to the OSM street network (some statistics for the region of Heidelberg have already been reported):

feature class | covered segments | avg. # of tracks
motorway 99% 98
primary 99% 21
secondary 96% 11
cycleway 91% 10
tertiary 95% 9
path 52% 2
residential 58% 2
footway 35% 2

However, the tool should be generic enough to work with any street network / GPS trajectories. Credits go to our student assistent Steffen John for his great work (again)! We welcome any feedback as well as further development of the tool by anyone who has an interest.

The Kick-Off Meeting of the European Chapter of the Socienty for Digital Earth (ISDE) was held last week at the EU Joint Research Center (JRC) in Ispra. Prof. Alexander Zipf attended the meeting on behalf of GIScience Research Group Heidelberg University.

Digital Earth is a global initiative to construct a comprehensive virtual representation of the planet. It is a collaborative effort between Earth sciences, space sciences and information sciences to monitor and forecast natural and human phenomena. The International Society for Digital Earth is a non-political, non-governmental and not-for-profit international organization, principally for promoting academic exchange, science and technology innovation, education, and international collaboration towards Digital Earth.

Our paper “Information fusion infrastructure for remote-sensing and in-situ sensor data to model people dynamics” by Hillen et al. (2014) has been selected by the editor of the International Journal of Image and Data Fusion to be freely accessible for downloading (editor’s choice). The paper presents a novel concept for an information fusion infrastructure to fuse remote-sensing data and in-situ measurements for the integration in real-time applications via a spatial data infrastructure (SDI). Enjoy reading it.

In a follow-up study we investigated how such a an information fusion infrastructure can be used to improve routing in crowds: Routing in Dense Human Crowds Using Smartphone Movement Data and Optical Aerial Imagery

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