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Peter Rottmann, Anne Driemel, Herman Haverkort, Heiko Röglin, and Jan-Henrik Haunert. Bicriteria shapes: hierarchical grouping and aggregation of polygons with an efficient graph-cut approach. ACM Transations on Spatial Algorithms and Systems, , 12 2024. Just Accepted
abstract
doi
bibtex
|
| An important task of pattern recognition and map generalization is to partition a set of disjoint polygons into groups and to aggregate the polygons within each group to a representative output polygon. We introduce a new method for this task called bicriteria shapes. Following a classical approach, we define the output polygons by merging the input polygons with a set of triangles that we select from a conforming Delaunay triangulation of the input polygons’ exterior. The innovation is that we control the selection of triangles with a bicriteria optimization model that is efficiently solved via graph cuts. In particular, we minimize a weighted sum that combines the total area of the output polygons and their total perimeter. In a basic problem, we ask for a single solution that is optimal for a preset parameter value. In a second problem, we ask for a set containing an optimal solution for every possible value of the parameter. We discuss how this set can be approximated with few solutions and show that it is hierarchically nested. Hence, the output is a hierarchical clustering that corresponds to multiple levels of detail. An evaluation with building footprints as input and a comparison with α-shapes that are based on the same underlying triangulation conclude the article. An advantage of bicriteria shapes compared to α-shapes is that the sequence of solutions for decreasing values of the parameter is monotone with respect to the total perimeter of the output polygons, resulting in a monotonically decreasing visual complexity. @article{rottmann2024bicriteriashapes,
abstract = {An important task of pattern recognition and map generalization is to partition a set of disjoint polygons into groups and to aggregate the polygons within each group to a representative output polygon. We introduce a new method for this task called bicriteria shapes. Following a classical approach, we define the output polygons by merging the input polygons with a set of triangles that we select from a conforming Delaunay triangulation of the input polygons’ exterior. The innovation is that we control the selection of triangles with a bicriteria optimization model that is efficiently solved via graph cuts. In particular, we minimize a weighted sum that combines the total area of the output polygons and their total perimeter. In a basic problem, we ask for a single solution that is optimal for a preset parameter value. In a second problem, we ask for a set containing an optimal solution for every possible value of the parameter. We discuss how this set can be approximated with few solutions and show that it is hierarchically nested. Hence, the output is a hierarchical clustering that corresponds to multiple levels of detail. An evaluation with building footprints as input and a comparison with α-shapes that are based on the same underlying triangulation conclude the article. An advantage of bicriteria shapes compared to α-shapes is that the sequence of solutions for decreasing values of the parameter is monotone with respect to the total perimeter of the output polygons, resulting in a monotonically decreasing visual complexity.},
address = {New York, NY, USA},
author = {Rottmann, Peter and Driemel, Anne and Haverkort, Herman and R\"{o}glin, Heiko and Haunert, Jan-Henrik},
doi = {10.1145/3705001},
issn = {2374-0353},
journal = {ACM Transations on Spatial Algorithms and Systems},
keywords = {Map generalization, aggregation, graph cuts, bicriteria optimization},
month = {12},
note = {Just Accepted},
publisher = {Association for Computing Machinery},
title = {Bicriteria Shapes: Hierarchical Grouping and Aggregation of Polygons with an Efficient Graph-Cut Approach},
url = {https://doi.org/10.1145/3705001},
year = {2024}
}
|
|
Annika Bonerath, Martin Nöllenburg, Soeren Terziadis, Markus Wallinger, and Jules Wulms. Boundary labeling in a circular orbit. In Stefan Felsner, and Karsten Klein, editors, volume 320 of Leibniz International Proceedings in Informatics (LIPIcs). 32nd International Symposium on Graph Drawing and Network Visualization (GD 2024), pages 22:1-22:17. Schloss Dagstuhl - Leibniz-Zentrum für Informatik, 2024.
doi
bibtex
|
| @inproceedings{Bonerath_GD_2024,
address = {Dagstuhl, Germany},
annote = {Keywords: External labeling, Orthoradial drawing, NP-hardness, Polynomial algorithms},
author = {Bonerath, Annika and N\"{o}llenburg, Martin and Terziadis, Soeren and Wallinger, Markus and Wulms, Jules},
booktitle = {32nd International Symposium on Graph Drawing and Network Visualization (GD 2024)},
doi = {10.4230/LIPIcs.GD.2024.22},
editor = {Felsner, Stefan and Klein, Karsten},
isbn = {978-3-95977-343-0},
issn = {1868-8969},
pages = {22:1--22:17},
publisher = {Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
series = {Leibniz International Proceedings in Informatics (LIPIcs)},
title = {{Boundary Labeling in a Circular Orbit}},
url = {https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.GD.2024.22},
urn = {urn:nbn:de:0030-drops-213060},
volume = {320},
year = {2024}
}
|
|
Axel Forsch, Ruben Kemna, Elmar Langetepe, and Jan-Henrik Haunert. Polyline morphing for animated schematic maps. Journal of Geovisualization and Spatial Analysis, 8, 2024.
abstract
doi
bibtex
|
| Thematic maps allow for the visual analysis of spatial data. When comparing two map states, preserving the mental map of a user facilitates the comparison. One way to achieve this is to use animated transitions between the states. This work presents an algorithm for computing such animations, called morphs, between schematized map objects, a technique particularly pertinent in urban mobility scenarios where schematic maps improve map legibility. In schematic maps, abstraction is used to reduce the visual complexity while still conveying information on a selected phenomenon. Our method ensures that the morph has four favorable properties: (1) it is self-intersection-free, (2) it maintains the schematization of the input features, (3) it is self-contained, and (4) every segment moves at its own constant velocity. We present an efficient algorithm to compute vertex traces and the timing of the morph. We evaluate our approach on isochrones visualizing travel times and on different layouts of schematic transit networks. The results show that the additional constraints we induce on the morphing only have a minor influence on the optimization target while they reduce the complexity of the animation. @article{ForschKemna2024,
abstract = {Thematic maps allow for the visual analysis of spatial data. When comparing two map states, preserving the mental map of a user facilitates the comparison. One way to achieve this is to use animated transitions between the states. This work presents an algorithm for computing such animations, called morphs, between schematized map objects, a technique particularly pertinent in urban mobility scenarios where schematic maps improve map legibility. In schematic maps, abstraction is used to reduce the visual complexity while still conveying information on a selected phenomenon. Our method ensures that the morph has four favorable properties: (1) it is self-intersection-free, (2) it maintains the schematization of the input features, (3) it is self-contained, and (4) every segment moves at its own constant velocity. We present an efficient algorithm to compute vertex traces and the timing of the morph. We evaluate our approach on isochrones visualizing travel times and on different layouts of schematic transit networks. The results show that the additional constraints we induce on the morphing only have a minor influence on the optimization target while they reduce the complexity of the animation.},
author = {Forsch, Axel and Kemna, Ruben and Langetepe, Elmar and Haunert, Jan-Henrik},
doi = {10.1007/s41651-024-00198-w},
issue = {37},
journal = {Journal of Geovisualization and Spatial Analysis},
pages = {},
title = {Polyline Morphing for Animated Schematic Maps},
volume = {8},
year = {2024}
}
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M. Hartig, S. Seifert, J.-H. Haunert, and S. Hüttel. Improving geographical accuracy of agricultural data: a probabilitstic spatial downscaling approach. In volume 59. Schriften der Gesellschaft für Wirtschafts- und Sozialwissenschaften des Landbaues e.V., pages 325-327. 2024.
abstract
bibtex
|
| Analyzing agricultural production requires detailed information about agroclimatic conditions at the farm's locations. The widely used Farm Accountancy Data Network (FADN) misses such information and provides farm locations only at NUTS-2 level. To identify farm locations more precisely, we extend the Bayesian probabilistic spatial downscaling approach of KEMPEN et al. (2011) utilizing only open access data, state-of-the-art regression techniques, and crop modeling. Furthermore, we include new data sources to improve the overall prediction accuracy. Preliminary results indicate that an improved spatial downscaling of FADN farm-level data from
NUTS-2 to NUTS-3 is possible using publicly available data sources. Our extension introduces an open-access approach to link FADN farm observations to weather and climate variables. @inproceedings{Hartig2024,
abstract = {Analyzing agricultural production requires detailed information about agroclimatic conditions at the farm's locations. The widely used Farm Accountancy Data Network (FADN) misses such information and provides farm locations only at NUTS-2 level. To identify farm locations more precisely, we extend the Bayesian probabilistic spatial downscaling approach of KEMPEN et al. (2011) utilizing only open access data, state-of-the-art regression techniques, and crop modeling. Furthermore, we include new data sources to improve the overall prediction accuracy. Preliminary results indicate that an improved spatial downscaling of FADN farm-level data from
NUTS-2 to NUTS-3 is possible using publicly available data sources. Our extension introduces an open-access approach to link FADN farm observations to weather and climate variables.},
author = {Hartig, M. and Seifert, S. and Haunert, J.-H. and Hüttel, S.},
booktitle = {{Schriften der Gesellschaft für Wirtschafts- und Sozialwissenschaften des Landbaues e.V.}},
pages = {325--327},
title = {Improving geographical accuracy of agricultural data: A probabilitstic spatial downscaling approach},
url = {https://www.gewisola.de/files/Tagungsband_finale_Version.pdf},
volume = {59},
year = {2024}
}
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Julius Knechtel, Peter Rottmann, Jan-Henrik Haunert, and Youness Dehbi. Semantic floorplan segmentation using self-constructing graph networks. Automation in Construction, 166:105649, 2024.
abstract
doi
bibtex
|
| This article presents an approach for the automatic semantic segmentation of floorplan images, predicting room boundaries (walls, doors, windows) and semantic labels of room types. A multi-task network was designed to represent and learn inherent dependencies by combining a Convolutional Neural Network to generate suitable features with a Graph Convolutional Network (GCN) to capture long-range dependencies. In particular, a Self-Constructing Graph module is applied to automatically induce an input graph for the GCN. Experiments on different datasets demonstrate the superiority and effectiveness of the multi-task network compared to state-of-the-art methods. The accurate results not only allow for subsequent vectorization of the existing floorplans but also for automatic inference of layout graphs including connectivity and adjacency relations. The latter could serve as basis to automatically sample layout graphs for architectural planning and design, predict missing links for unobserved parts for as-built building models and learn important latent topological and architectonic patterns. @article{Knechtel2024FloorplanSCG,
abstract = {This article presents an approach for the automatic semantic segmentation of floorplan images, predicting room boundaries (walls, doors, windows) and semantic labels of room types. A multi-task network was designed to represent and learn inherent dependencies by combining a Convolutional Neural Network to generate suitable features with a Graph Convolutional Network (GCN) to capture long-range dependencies. In particular, a Self-Constructing Graph module is applied to automatically induce an input graph for the GCN. Experiments on different datasets demonstrate the superiority and effectiveness of the multi-task network compared to state-of-the-art methods. The accurate results not only allow for subsequent vectorization of the existing floorplans but also for automatic inference of layout graphs including connectivity and adjacency relations. The latter could serve as basis to automatically sample layout graphs for architectural planning and design, predict missing links for unobserved parts for as-built building models and learn important latent topological and architectonic patterns.},
author = {Knechtel, Julius and Rottmann, Peter and Haunert, Jan-Henrik and Dehbi, Youness},
doi = {10.1016/j.autcon.2024.105649},
journal = {Automation in Construction},
pages = {105649},
title = {Semantic Floorplan Segmentation Using Self-Constructing Graph Networks},
url = {https://www.sciencedirect.com/science/article/pii/S0926580524003856},
volume = {166},
year = {2024}
}
|
|
Reza Arabsheibani, Jan-Henrik Haunert, Stephan Winter, and Martin Tomko. Strategic allocation of landmarks to reduce uncertainty in indoor navigation. Computers, Environment and Urban Systems, 114:102198, 2024.
abstract
doi
bibtex
|
| Indoor navigation systems often rely on verbal, turn-based route instructions. These can, at times, be ambiguous at complex decision points with multiple paths intersecting under angles that are not well distinguished by the turn grammar used. Landmarks can be included into turn instructions to reduce this ambiguity. Here, we propose an approach to optimize landmark allocation to improve the clarity of route instructions. This study assumes that landmark locations are constrained to a pre-determined set of slots. We select a minimum-size subset of the set of all slots and allocate it with landmarks, such that the navigation ambiguity is resolved. Our methodology leverages computational geometric analysis, graph algorithms, and optimization formulations to strategically incorporate landmarks into indoor route instructions. We propose a method to optimize landmark allocation in indoor navigation guidance systems, improving the clarity of route instructions at complex decision points that are inadequately served by turn-based instructions alone. @article{Arabsheibani2024,
_note = {Accepted for publication.},
abstract = {Indoor navigation systems often rely on verbal, turn-based route instructions. These can, at times, be ambiguous at complex decision points with multiple paths intersecting under angles that are not well distinguished by the turn grammar used. Landmarks can be included into turn instructions to reduce this ambiguity. Here, we propose an approach to optimize landmark allocation to improve the clarity of route instructions. This study assumes that landmark locations are constrained to a pre-determined set of slots. We select a minimum-size subset of the set of all slots and allocate it with landmarks, such that the navigation ambiguity is resolved. Our methodology leverages computational geometric analysis, graph algorithms, and optimization formulations to strategically incorporate landmarks into indoor route instructions. We propose a method to optimize landmark allocation in indoor navigation guidance systems, improving the clarity of route instructions at complex decision points that are inadequately served by turn-based instructions alone.},
author = {Arabsheibani, Reza and Haunert, Jan-Henrik and Winter, Stephan and Tomko, Martin},
doi = {10.1016/j.compenvurbsys.2024.102198},
issn = {0198-9715},
journal = {Computers, Environment and Urban Systems},
pages = {102198},
title = {Strategic Allocation of Landmarks to Reduce Uncertainty in Indoor Navigation},
volume = {114},
year = {2024}
}
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|
Alexander Naumann, Annika Bonerath, and Jan-Henrik Haunert. Many-to-many polygon matching \`a la Jaccard. In Proc. European Symposium on Algorithms (ESA'24), pages 90:1-90:15. 2024.
abstract
doi
bibtex
|
| Integration of spatial data is a major field of research. An important task of data integration is finding correspondences between entities. Here, we focus on combining building footprint data from cadastre and from volunteered geographic information, in particular OpenStreetMap. Previous research on this topic has led to exact 1:1 matching approaches and heuristic m:n matching approaches, most of which are lacking a mathematical problem definition. We introduce a model for many-to-many polygon matching based on the well-established Jaccard index. This is a natural extension to the existing 1:1 matching approaches. We show that the problem is NP-complete and a naive approach via integer programming fails easily. By analyzing the structure of the problem in detail, we can reduce the number of variables significantly. This approach yields an optimal m:n matching even for large real-world instances with appropriate running time. In particular, for the set of all building footprints of the city of Bonn (119,300 / 97,284 polygons) it yielded an optimal solution in approximately 1 hour. @inproceedings{NaumannEtAl2024,
abstract = {Integration of spatial data is a major field of research. An important task of data integration is finding correspondences between entities. Here, we focus on combining building footprint data from cadastre and from volunteered geographic information, in particular OpenStreetMap. Previous research on this topic has led to exact 1:1 matching approaches and heuristic m:n matching approaches, most of which are lacking a mathematical problem definition. We introduce a model for many-to-many polygon matching based on the well-established Jaccard index. This is a natural extension to the existing 1:1 matching approaches. We show that the problem is NP-complete and a naive approach via integer programming fails easily. By analyzing the structure of the problem in detail, we can reduce the number of variables significantly. This approach yields an optimal m:n matching even for large real-world instances with appropriate running time. In particular, for the set of all building footprints of the city of Bonn (119,300 / 97,284 polygons) it yielded an optimal solution in approximately 1 hour.},
author = {Naumann, Alexander and Bonerath, Annika and Haunert, Jan-Henrik},
booktitle = {Proc. European Symposium on Algorithms (ESA'24)},
doi = {10.4230/LIPIcs.ESA.2024.90},
pages = {90:1--90:15},
title = {Many-to-many polygon matching \`{a} la {Jaccard}},
year = {2024}
}
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|
Anna-Maria Bolte, Benjamin Niedermann, Thomas Kistemann, Jan-Henrik Haunert, Youness Dehbi, and Theo Kötter. The green window view index: automated multi-source visibility analysis for a multi-scale assessment of green window views. Landscape Ecology, 39, 2024.
doi
bibtex
|
| @article{BolteEtAl2024,
author = {Bolte, Anna-Maria and Niedermann, Benjamin and Kistemann, Thomas and Haunert, Jan-Henrik and Dehbi, Youness and Kötter, Theo},
doi = {10.1007/s10980-024-01871-7},
issue = {3},
journal = {Landscape Ecology},
title = {The green window view index: automated multi-source visibility analysis for a multi-scale assessment of green window views},
volume = {39},
year = {2024}
}
|
|
Xinyuan Yan, Peter Rodgers, Peter Rottmann, Daniel Archambault, Jan-Henrik Haunert, and Bei Wang. Eulermerge: simplifying euler diagrams through set merges. In volume 14981 of Lecture Notes in Computer Science. Diagrams 2024: 14th International Conference on the Theory and Application of Diagrams, pages 190-206. Springer, 2024.
abstract
doi
bibtex
|
| Euler diagrams are an intuitive and popular method to visualize set-based data. In an Euler diagram, each set is represented as a closed curve, and set intersections are shown by curve overlaps. However, Euler diagrams are not visually scalable and automatic layout techniques struggle to display real-world data sets in a comprehensible way. Prior state-of-the-art approaches can embed Euler diagrams by splitting a closed curve into multiple curves so that a set is represented by multiple disconnected enclosed areas. In addition, these methods typically result in multiple curve segments being drawn concurrently. Both of these features significantly impede understanding. In this paper, we present a new and scalable method for embedding Euler diagrams using set merges. Our approach simplifies the underlying data to ensure that each set is represented by a single, connected enclosed area and that the diagram is drawn without curve concurrency, leading to wellformed and understandable Euler diagrams. @inproceedings{YanEtAl2024,
abstract = {Euler diagrams are an intuitive and popular method to visualize set-based data. In an Euler diagram, each set is represented as a closed curve, and set intersections are shown by curve overlaps. However, Euler diagrams are not visually scalable and automatic layout techniques struggle to display real-world data sets in a comprehensible way. Prior state-of-the-art approaches can embed Euler diagrams by splitting a closed curve into multiple curves so that a set is represented by multiple disconnected enclosed areas. In addition, these methods typically result in multiple curve segments being drawn concurrently. Both of these features significantly impede understanding. In this paper, we present a new and scalable method for embedding Euler diagrams using set merges. Our approach simplifies the underlying data to ensure that each set is represented by a single, connected enclosed area and that the diagram is drawn without curve concurrency, leading to wellformed and understandable Euler diagrams.},
author = {Yan, Xinyuan and Rodgers, Peter and Rottmann, Peter and Archambault, Daniel and Haunert, Jan-Henrik and Wang, Bei},
booktitle = {Diagrams 2024: 14th International Conference on the Theory and Application of Diagrams},
doi = {10.1007/978-3-031-71291-3_16},
pages = {190--206},
publisher = {Springer},
series = {Lecture Notes in Computer Science},
title = {{EulerMerge: Simplifying Euler Diagrams Through Set Merges}},
volume = {14981},
year = {2024}
}
|
|
Annika Bonerath, Martin Nöllenburg, Soeren Terziadis, Markus Wallinger, and Jules Wulms. On orbital labeling with circular contours. In Proceedings of the 40th European Workshop on Computational Geometry (EuroCG'24). 2024. Preprint.
bibtex
|
| @inproceedings{b-oolcc-preprint-24,
author = {Bonerath, Annika and N{\"o}llenburg, Martin and Terziadis, Soeren and Wallinger, Markus and Wulms, Jules},
booktitle = {Proceedings of the 40th European Workshop on Computational Geometry (EuroCG'24)},
note = {Preprint.},
title = {{On Orbital Labeling with Circular Contours}},
url = {https://eurocg2024.math.uoi.gr/data/uploads/paper_67.pdf},
year = {2024}
}
|
|
Sven Gedicke, Shiyaza Risvi, and Jan-Henrik Haunert. Report on the FAIRagro Workshop on Data Quality for Data Analytics in Agrosystem Science (DQ4DA). Technical Report, University of Bonn, 2024.
doi
bibtex
|
| @techreport{gedicke2024dq4da,
author = {Gedicke, Sven and Risvi, Shiyaza and Haunert, Jan-Henrik},
doi = {10.5281/zenodo.10697161},
institution = {University of Bonn},
title = {{R}eport on the {FAIR}agro {W}orkshop on {D}ata {Q}uality for {D}ata {A}nalytics in {A}grosystem {S}cience ({DQ4DA})},
year = {2024}
}
|
|
Julius Knechtel, Weilian Li, Yannick Orgeig, Jan-Henrik Haunert, and Youness Dehbi. Immersive Virtual Reality to Verify the As-built State of Electric Line Networks in Buildings. In Thomas H. Kolbe, Andreas Donaubauer, and Christof Beil, editors. Recent Advances in 3D Geoinformation Science (Proceedings of the 18th 3D GeoInfo Conference 2023, Munich), pages 129-143. Springer Nature Switzerland, 2024.
abstract
doi
bibtex
|
| Immersive virtual reality (IVR) allows viewing abstract concepts and entities in a three dimensional (3D) visuospatial environment. In this paper, we innovatively introduced IVR technology into the verification of the as-built state of electric line networks in buildings. On the one hand, using a reasoning-based estimation of electric networks as a starting point, we demonstrated the usability of IVR technology for verifying installed utilities in buildings. On the other hand, we established the communication between the Reasoner and the practitioner and also simulated the verification action of electric line networks in buildings in the real world. The principal findings of this work pave the way for a subsequent and systematic evaluation of the different reasoning strategies for estimating and generating the as-built state of building utilities. @inproceedings{knechtel2024immersiveVRElectricNetworks,
abstract = {Immersive virtual reality (IVR) allows viewing abstract concepts and entities in a three dimensional (3D) visuospatial environment. In this paper, we innovatively introduced IVR technology into the verification of the as-built state of electric line networks in buildings. On the one hand, using a reasoning-based estimation of electric networks as a starting point, we demonstrated the usability of IVR technology for verifying installed utilities in buildings. On the other hand, we established the communication between the Reasoner and the practitioner and also simulated the verification action of electric line networks in buildings in the real world. The principal findings of this work pave the way for a subsequent and systematic evaluation of the different reasoning strategies for estimating and generating the as-built state of building utilities.},
address = {Cham},
author = {Knechtel, Julius and Li, Weilian and Orgeig, Yannick and Haunert, Jan-Henrik and Dehbi, Youness},
booktitle = {Recent Advances in 3D Geoinformation Science (Proceedings of the 18th 3D GeoInfo Conference 2023, Munich)},
doi = {10.1007/978-3-031-43699-4\_8},
editor = {Kolbe, Thomas H. and Donaubauer, Andreas and Beil, Christof},
isbn = {978-3-031-43699-4},
pages = {129--143},
publisher = {Springer Nature Switzerland},
title = {{I}mmersive {V}irtual {R}eality to {V}erify the {A}s-built {S}tate of {E}lectric {L}ine {N}etworks in {B}uildings},
year = {2024}
}
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|
Farzane Mohseni, AmirHossein Ahrari, Jan-Henrik Haunert, and Carsten Montzka. The synergies of smap enhanced and modis products in a random forest regression for estimating 1 km soil moisture over africa using google earth engine. Big Earth Data, 8(1):33-57, 2024.
doi
bibtex
|
| @article{Mohseni2023,
author = {Mohseni, Farzane and Ahrari, AmirHossein and Haunert, Jan-Henrik and Montzka, Carsten},
doi = {10.1080/20964471.2023.2257905},
journal = {Big Earth Data},
number = {1},
pages = {33-57},
title = {The synergies of SMAP enhanced and MODIS products in a random forest regression for estimating 1 km soil moisture over Africa using Google Earth Engine},
volume = {8},
year = {2024}
}
|
|
Axel Forsch, Stefan Funke, Jan-Henrik Haunert, and Sabine Storandt. Efficient mining of volunteered trajectory datasets. In Dirk Burghardt, Elena Demidova, and Daniel A. Keim, editors. Volunteered Geographic Information: Interpretation, Visualization and Social Context, pages 43-77. Springer Nature Switzerland, 2024.
abstract
doi
bibtex
|
| With the ubiquity of mobile devices that are capable of tracking positions (be it via GPS or Wi-Fi/mobile network localization), there is a continuous stream of location data being generated every second. These location measurements are typically not considered individually but rather as sequences, each of which reflects the movement of one person or vehicle, which we call trajectory. This chapter presents new algorithmic approaches to process and visualize trajectories both in the network-constrained and the unconstrained case. @incollection{forsch2024volunteered,
abstract = {With the ubiquity of mobile devices that are capable of tracking positions (be it via GPS or Wi-Fi/mobile network localization), there is a continuous stream of location data being generated every second. These location measurements are typically not considered individually but rather as sequences, each of which reflects the movement of one person or vehicle, which we call trajectory. This chapter presents new algorithmic approaches to process and visualize trajectories both in the network-constrained and the unconstrained case.},
address = {Cham},
author = {Forsch, Axel and Funke, Stefan and Haunert, Jan-Henrik and Storandt, Sabine},
booktitle = {Volunteered Geographic Information: Interpretation, Visualization and Social Context},
doi = {10.1007/978-3-031-35374-1_3},
editor = {Burghardt, Dirk and Demidova, Elena and Keim, Daniel A.},
isbn = {978-3-031-35374-1},
pages = {43--77},
publisher = {Springer Nature Switzerland},
title = {Efficient Mining of Volunteered Trajectory Datasets},
year = {2024}
}
|
|
Dorian Baltzer, Jan-Henrik Haunert, and Axel Forsch. Visualizing the influence of new public transport infrastructure on travel times. KN - Journal of Cartography and Geographic Information, 74:107-119, 2024.
abstract
doi
bibtex
|
| Due to the global climate change and increasing traffic volumes in cities, a shift from individual to public and multimodal
transport is aspired. Travel time is one of the most important aspects for many people when choosing their mode of trans-
portation. This leads to the requirement that changes in travel times have to be considered when planning new public trans-
port infrastructure. This research paper presents and compares different techniques for visualizing the impact of new lines
in existing public transport networks on travel times. The general approach of simulating timetable data and calculating
intermodal travel times considering public transport and walking is being applied to two current infrastructure projects in
the city of Bonn and the surrounding region. The created maps generally aim to visualize the spread in travel times between
existing and extended transportation networks discretized by different spatial units such as rectangles or postal code areas. In
comparison to other common methods which typically require two maps for two different scenarios (e.g. in case of isochro-
nes), our approach gives the opportunity to combine all relevant information within one map. It is also shown how to apply
bivariate choropleth maps for displaying travel times and how to visualize improvements in the accessibility of multiple
target points of interest at once. @article{Baltzer2024,
abstract = {Due to the global climate change and increasing traffic volumes in cities, a shift from individual to public and multimodal
transport is aspired. Travel time is one of the most important aspects for many people when choosing their mode of trans-
portation. This leads to the requirement that changes in travel times have to be considered when planning new public trans-
port infrastructure. This research paper presents and compares different techniques for visualizing the impact of new lines
in existing public transport networks on travel times. The general approach of simulating timetable data and calculating
intermodal travel times considering public transport and walking is being applied to two current infrastructure projects in
the city of Bonn and the surrounding region. The created maps generally aim to visualize the spread in travel times between
existing and extended transportation networks discretized by different spatial units such as rectangles or postal code areas. In
comparison to other common methods which typically require two maps for two different scenarios (e.g. in case of isochro-
nes), our approach gives the opportunity to combine all relevant information within one map. It is also shown how to apply
bivariate choropleth maps for displaying travel times and how to visualize improvements in the accessibility of multiple
target points of interest at once.},
author = {Baltzer, Dorian and Haunert, Jan-Henrik and Forsch, Axel},
doi = {https://doi.org/10.1007/s42489-024-00167-9},
journal = {KN - Journal of Cartography and Geographic Information},
pages = {107--119},
publisher = {Springer},
title = {Visualizing the Influence of New Public Transport Infrastructure on Travel Times},
url = {https://link.springer.com/article/10.1007/s42489-024-00167-9},
volume = {74},
year = {2024}
}
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Weilian Li, Lukas Arzoumanidis, Jannik Matijevic, Daham MMohammed Mustafa, Peter Rottmann, Jan-Henrik Haunert, and Youness Dehbi. Safety assessment of cycling routes in urban environments. The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, XLVIII-4/W10-2024:125-130, 2024.
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| As one of the most well-known forms of active mobility, cycling is an environmentally friendly way to explore a destination, becoming increasingly prevalent worldwide. However, safety is the most severe issue facing cyclists and the essential factor for people who are hesitant to use bikes. In this context, we propose a safety assessment method for cycling routes in urban environments. This work presents how to automatically generate a safe cycling map integrating volunteered geographic information with GIS analysis. We start by extracting the indicators that can possibly contribute to cycling safety from OpenStreetMap. Then, we set up a multivariate linear regression equation to solve the importance of indicators. Afterward, we generate a weighted graph model that represents cycling safety. Taking the City of Bonn, Germany, as an example, we implement our approach for this region. The experiment results show that Bonn is a city for safe cycling, confirming the claim that Bonn is a bike-friendly city. Our findings can also be used to plan the safest route for cycling, thereby enhancing the overall biking experience in Bonn. @article{li2024safetyassessment,
abstract = {As one of the most well-known forms of active mobility, cycling is an environmentally friendly way to explore a destination, becoming increasingly prevalent worldwide. However, safety is the most severe issue facing cyclists and the essential factor for people who are hesitant to use bikes. In this context, we propose a safety assessment method for cycling routes in urban environments. This work presents how to automatically generate a safe cycling map integrating volunteered geographic information with GIS analysis. We start by extracting the indicators that can possibly contribute to cycling safety from OpenStreetMap. Then, we set up a multivariate linear regression equation to solve the importance of indicators. Afterward, we generate a weighted graph model that represents cycling safety. Taking the City of Bonn, Germany, as an example, we implement our approach for this region. The experiment results show that Bonn is a city for safe cycling, confirming the claim that Bonn is a bike-friendly city. Our findings can also be used to plan the safest route for cycling, thereby enhancing the overall biking experience in Bonn.},
author = {Li, Weilian and Arzoumanidis, Lukas and Matijevic, Jannik and Mustafa, Daham MMohammed and Rottmann, Peter and Haunert, Jan-Henrik and Dehbi, Youness},
doi = {10.5194/isprs-archives-XLVIII-4-W10-2024-125-2024},
journal = {The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences},
pages = {125--130},
title = {Safety Assessment of Cycling Routes in Urban Environments},
url = {https://isprs-archives.copernicus.org/articles/XLVIII-4-W10-2024/125/2024/},
volume = {XLVIII-4/W10-2024},
year = {2024}
}
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Peter Rottmann, Peter Rodgers, Xinyuan Yan, Daniel Archambault, Bei Wang, and Jan-Henrik Haunert. Generating euler diagrams through combinatorial optimization. Computer Graphics Forum, 43(3), 2024.
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| Can a given set system be drawn as an Euler diagram? We present the first method that correctly decides this question for arbitrary set systems if the Euler diagram is required to represent each set with a single connected region. If the answer is yes, our method constructs an Euler diagram. If the answer is no, our method yields an Euler diagram for a simplified version of the set system, where a minimum number of set elements have been removed. Further, we integrate known wellformedness criteria for Euler diagrams as additional optimization objectives into our method. Our focus lies on the computation of a planar graph that is embedded in the plane to serve as the dual graph of the Euler diagram. Since even a basic version of this problem is known to be NP-hard, we choose an approach based on integer linear programming (ILP), which allows us to compute optimal solutions with existing mathematical solvers. For this, we draw upon previous research on computing planar supports of hypergraphs and adapt existing ILP building blocks for contiguity-constrained spatial unit allocation and the maximum planar subgraph problem. To generate Euler diagrams for large set systems, for which the proposed simplification through element removal becomes indispensable, we also present an efficient heuristic. We report on experiments with data from MovieDB and Twitter. Over all examples, including 850 non-trivial instances, our exact optimization method failed only for one set system to find a solution without removing a set element. However, with the removal of only a few set elements, the Euler diagrams can be substantially improved with respect to our wellformedness criteria. @article{rottmann2024generating,
abstract = {Can a given set system be drawn as an Euler diagram? We present the first method that correctly decides this question for arbitrary set systems if the Euler diagram is required to represent each set with a single connected region. If the answer is yes, our method constructs an Euler diagram. If the answer is no, our method yields an Euler diagram for a simplified version of the set system, where a minimum number of set elements have been removed. Further, we integrate known wellformedness criteria for Euler diagrams as additional optimization objectives into our method. Our focus lies on the computation of a planar graph that is embedded in the plane to serve as the dual graph of the Euler diagram. Since even a basic version of this problem is known to be NP-hard, we choose an approach based on integer linear programming (ILP), which allows us to compute optimal solutions with existing mathematical solvers. For this, we draw upon previous research on computing planar supports of hypergraphs and adapt existing ILP building blocks for contiguity-constrained spatial unit allocation and the maximum planar subgraph problem. To generate Euler diagrams for large set systems, for which the proposed simplification through element removal becomes indispensable, we also present an efficient heuristic. We report on experiments with data from MovieDB and Twitter. Over all examples, including 850 non-trivial instances, our exact optimization method failed only for one set system to find a solution without removing a set element. However, with the removal of only a few set elements, the Euler diagrams can be substantially improved with respect to our wellformedness criteria.},
author = {Rottmann, Peter and Rodgers, Peter and Yan, Xinyuan and Archambault, Daniel and Wang, Bei and Haunert, Jan-Henrik},
doi = {10.1111/cgf.15089},
eprint = {https://onlinelibrary.wiley.com/doi/pdf/10.1111/cgf.15089},
journal = {Computer Graphics Forum},
keywords = {CCS Concepts, • Human-centered computing → Information visualization, • Theory of computation → Integer programming, • Mathematics of computing → Hypergraphs},
number = {3},
title = {Generating Euler Diagrams Through Combinatorial Optimization},
url = {https://onlinelibrary.wiley.com/doi/abs/10.1111/cgf.15089},
volume = {43},
year = {2024}
}
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Dorian Baltzer, Alexander Naumann, Stephan Rosenberg, and Jan-Henrik Haunert. Automatically generating virtual tours based on dense sets of 360° imagery. Abstracts of the ICA, 7:8, 2024.
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| @article{baltzer2024automatically,
author = {Baltzer, Dorian and Naumann, Alexander and Rosenberg, Stephan and Haunert, Jan-Henrik},
doi = {10.5194/ica-abs-7-8-2024},
journal = {Abstracts of the ICA},
pages = {8},
publisher = {Copernicus Publications G{\"o}ttingen, Germany},
title = {Automatically generating virtual tours based on dense sets of 360° imagery},
url = {https://ica-abs.copernicus.org/articles/7/8/2024/ica-abs-7-8-2024.pdf},
volume = {7},
year = {2024}
}
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