Program
WEDNESDAY  

TIME (JST)  ACTIVITY  MIN  AUTHORS  
09:00  09:30  Registration  
09:30  09:35  Opening  
Session 1  Chair: Emilio Di Giacomo  
09:35  09:55  Unavoidable patterns in complete simple topological graphs (best T1)  20  Andrew Suk and Ji Zeng  
09:55  10:10  Empty Triangles in Generalized Twisted Drawings of K_n  15  Alfredo Garcia, Javier Tejel, Birgit Vogtenhuber and Alexandra Weinberger  
10:10  10:25  Compatible Spanning Trees in Simple Drawings of $K_n$  15  Rosna Paul, Oswin Aichholzer, Kristin Knorr, Birgit Vogtenhuber, Johannes Obenaus, Wolfgang Mulzer, Nicolas El Maalouly, Meghana M Reddy and Alexandra Weinberger  
10:25  10:40  Shooting Stars in Simple Drawings of K_{m,n}  15  Oswin Aichholzer, Alfredo Garcia, Irene Parada, Birgit Vogtenhuber and Alexandra Weinberger  
10:40  11:10  Break  
Session 2  Chair: Philipp Kindermann  
11:10  11:30  Small PointSets Supporting Graph Stories  20  Giuseppe Di Battista, Walter Didimo, Luca Grilli, Fabrizio Grosso, Giacomo Ortali, Maurizio Patrignani and Alessandra Tappini  
11:30  11:50  On the Complexity of the Storyplan Problem  20  Carla Binucci, Emilio Di Giacomo, William J. Lenhart, Giuseppe Liotta, Fabrizio Montecchiani, Martin Nöllenburg and Antonios Symvonis  
11:50  12:10  On Time and Space: An Experimental Study on Graph Structural and Temporal Representations  20  Velitchko Filipov, Alessio Arleo, Markus Bögl and Silvia Miksch  
12:10  12:30  Improved Scheduling of Morphing Edge Drawing  20  Kazuo Misue  
12:30  14:00  Lunch  
Session 3  Chair: Ken Wakita  
14:00  14:20  Quasiplanar graphs, string graphs, and the ErdősGallai problem  20  Jacob Fox, Janos Pach and Andrew Suk  
14:20  14:40  The thickness of fanplanar graphs is at most three  20  Otfried Cheong, Maximilian Pfister and Lena Schlipf  
14:40  15:00  Arrangements of Pseudocircles: On Digons and Triangles  20  Stefan Felsner, Sandro Roch and Manfred Scheucher  
15:00  15:20  Mutual Witness Gabriel Drawings of Complete Bipartite Graphs  20  William Lenhart and Giuseppe Liotta  
15:20  15:30  Poster pitches  
15:30  16:30  Break + poster  
16:30  18:00  Contest 
THURSDAY  

TIME (JST)  ACTIVITY  MIN  AUTHORS  
09:00  09:30  Registration  
Keynote I  Chair: Patrizio Angelini  
09:30  10:30  Positions in Social and Other Spaces  60  Ulrik Brandes  
10:30  11:00  Break  
Session 4  Chair: Jiaxi Nie  
11:00  11:20  Planarizing Graphs and their Drawings by Vertex Splitting  20  Soeren Nickel, Martin Nöllenburg, Manuel Sorge, Anaïs Villedieu, HsiangYun Wu and Jules Wulms  
11:20  11:35  An FPT Algorithm for Bipartite Vertex Splitting  15  Reyan Ahmed, Stephen Kobourov and Myroslav Kryven  
11:35  11:50  Queue Layouts of TwoDimensional Posets  15  Sergey Pupyrev  
11:50  12:10  The RiqueNumber of Graphs  20  Michael Bekos, Stefan Felsner, Philipp Kindermann, Stephen Kobourov, Jan Kratochvíl and Ignaz Rutter  
12:10  12:25  Recognizing DAGs with PageNumber 2 is NPcomplete  15  Michael Bekos, Giordano Da Lozzo, Fabrizio Frati, Martin Gronemann, Tamara Mchedlidze and Chrysanthi Raftopoulou  
12:30  14:00  Lunch  
Session 5  In Memoriam: Prof. Takao Nishizeki  Chair: Md. Saidur Rahman  
14:00  14:05  Obituary Prof. Nishizeki  
14:05  14:25  StrictlyConvex Drawings of 3Connected Planar Graphs  20  Michael Bekos, Martin Gronemann, Fabrizio Montecchiani and Antonios Symvonis  
14:25  14:45  Rectilinear Planarity of Partial 2Trees  20  Walter Didimo, Michael Kaufmann, Giuseppe Liotta and Giacomo Ortali  
14:45  15:05  Unitlength Rectangular Drawings of Graphs  20  Carlos Alegría, Giordano Da Lozzo, Giuseppe Di Battista, Fabrizio Frati, Fabrizio Grosso and Maurizio Patrignani  
15:05  15:25  Planar Confluent Orthogonal Drawings of 4Modal Digraphs  20  Sabine Cornelsen and Gregor Diatzko  
15:25  16:00  Break  
16:00  17:30  Business meeting 
FRIDAY  

TIME (JST)  ACTIVITY  MIN  AUTHORS  
09:00  09:30  Registration  
Keynote I  Chair: Reinhard von Hanxleden  
09:30  10:30  Graph Drawing for Thinking Support  60  Kazuo Misue  
10:30  11:00  Break  
Session 6  Chair: Takayuki Itoh  
11:00  11:20  FORBID: Fast Overlap Removal By Stochastic Gradient Descent for Graph Drawing (best T2)  20  Loann Giovannangeli, Frédéric Lalanne, Romain Giot and Romain Bourqui  
11:20  11:40  Spherical Graph Drawing by Multidimensional Scaling  20  Jacob Miller, Vahan Huroyan and Stephen Kobourov  
11:40  12:00  ShapeFaithful Graph Drawings  20  Amyra Meidiana, SeokHee Hong and Peter Eades  
12:00  12:20  Visualizing Evolving Trees  20  Kathryn Gray, Mingwei Li, Abu Reyan Ahmed and Stephen Kobourov  
12:30  14:00  Lunch  
Session 7  Chair: Andrew Suk  
14:00  14:20  Morphing Rectangular Duals  20  Steven Chaplick, Philipp Kindermann, Jonathan Klawitter, Ignaz Rutter and Alexander Wolff  
14:20  14:40  Coloring Mixed and Directional Interval Graphs  20  Grzegorz Gutowski, Florian Mittelstädt, Ignaz Rutter, Joachim Spoerhase, Alexander Wolff and Johannes Zink  
14:40  15:00  OutsideObstacle Representations with All Vertices on the Outer Face  20  Oksana Firman, Philipp Kindermann, Jonathan Klawitter, Boris Klemz, Felix Klesen and Alexander Wolff  
15:00  15:30  Break  
Session 8  Chair: Sabine Cornelsen  
15:30  15:50  Computing a Feedback Arc Set Using PageRank  20  Vasileios Geladaris, Panagiotis Lionakis and Ioannis Tollis  
15:50  16:10  stOrientations with Few Transitive Edges  20  Carla Binucci, Walter Didimo and Maurizio Patrignani  
16:10  16:30  Testing Upward Planarity of Partial 2Trees  20  Steven Chaplick, Emilio Di Giacomo, Fabrizio Frati, Robert Ganian, Chrysanthi Raftopoulou and Kirill Simonov  
16:30  16:50  Visibility representations of toroidal and Kleinbottle graphs  20  Therese Biedl  
16:50  17:10  Voting best presentation and closing 
Keynote Speakers
Ulrik Brandes (ETH Zürich, Switzerland)
Title:
Positions in Social and Other Spaces
Abstract:
Social networks are a traditional source of inspiration for graph drawing methods, and their analysis continues to motivate a variety of layout constraints and objectives.
In recent years, my research has increasingly been focused on methodological questions related to social networks and other applied areas of network science. This has led to a framework, dubbed the positional approach, which facilitates adaptive and theoryinformed empirical network data science. It turns out, however, that it is also another rich source of algorithmic and visualization problems. The present contribution is therefore forwardlooking, using results from the past few years to point out possible directions for future research in three parts.
In the first part, I review some defining aspects of the positional approach to network science with an eye towards challenges for graph drawing and network visualization. These are centered largely on combinatorial problems involving preorders and graph classes.
A particularly strong link between influence processes on social networks and barycentric graph drawing is discussed in the second part. Using concepts from above, this extends naturally to calls for novel scaling methods and research on graph embeddings.
The final part is about collectice behavior in the context of team sports. More precisely, I will outline problems arising from our most recent efforts of performance analysis in association football (soccer) using proximity graphs.
Biography:
Ulrik Brandes is professor for social networks at ETH Zürich. His background is in computer science; he obtained a Diploma degree from RWTH Aachen and a doctoral degree from the University of Konstanz with a dissertation on graph drawing. After his habilitation in 2002 he became associate professor at the University of Passau in the same year, and professor for algorithmics at the University of Konstanz one year later. He is vicepresident of the International Network for Social Network Analysis (INSNA), coordinating editor of Network Science, and on the editorial boards of Social Networks, Journal of Mathematical Sociology, Journal of Graph Algorithms and Applications, and Computer Science Review. From 20072014 he served on the Graph Drawing Steering Committee.
His main interests are in network analysis and visualization, with application to social networks in particular. He is a coauthor of the visone software for network analysis and the GraphML data format. Following a DFGfunded Reinhart KoselleckProject (20112017) on Social Network Algorithmics, he takes a shot at improving the methodological foundations of network science. As a principal investigator in the ERC Synergy Project NEXUS 1492 (20132019) he worked on reconstructing archaeological networks from fragmented and heterogeneous observations. Currently, he is devoting more time to network representations in sports analytics.
Kazuo Misue (University of Tsukuba, Japan)
Title:
Graph Drawing for Thinking Support
Abstract:
In human intellectual activities, organizing the objects of thought is an important task. When the object of thought is large or complex, it is difficult for many people to organize it in their minds. In such cases, it is effective to take these objects out of our minds and observe them externally. When we externalize our thoughts in this way, the form of representation of the objects also influences the effectiveness and efficiency of our thinking process. When we organize fragments of information, we often establish a relationship between two fragments and group several fragments together. In the case of externalization, these relationships and groups are represented graphically, that is, the words and figures representing the fragments are connected by line segments or surrounded by closed lines. Some of the socalled "ideation techniques" systematize such diagramming methods. The "KJ method" is one such technique.
In the diagram used in the KJ method, if each fragment of information is represented by a node, links connecting two nodes and closed curves surrounding the nodes are used. Moreover, in the KJ method, we can organize objects of thought by transforming a compound diagram that comprises a nodelink diagram and an Euler diagram. The original KJ method was designed to be performed entirely by hand using analog tools such as cards, pens, and cords, and it was not intended for the use with computers. This, however, is also a factor that discourages the active use of the KJ method, although its usefulness as an ideation technique has been recognized. For example, despite the effectiveness of repeated drawing of diagrams on the same topic, we often do so only once because repeating the process requires time and effort.
The transformation operation of a compound diagram can be viewed as the transformation operation of a compound graph; to obtain a visual representation of such a compound graph, automatic drawing techniques are required. If we can separate the transforming operations of a compound diagram from the thinking process and if the transforming operations can be supported by a computer, the hurdles associated with the use of such an ideation technique will be reduced, and the efficiency of the ideation process could increase. Eventually, this increased efficiency will lead to an improvement in the quality of the ideation process and its products.
This talk introduces the research and development that has been carried out with this motivation.
Biography:
Kazuo Misue is a professor at the Faculty of Engineering, Information and Systems, University of Tsukuba, Japan. He received a BSc and an MSc from Tokyo University of Science in 1984 and 1986. He received a Ph.D. in engineering from the University of Tokyo in 1997. He joined Fujitsu Limited in 1986. He worked at the International Institute for Advanced Study of Social Information Sciences, where he worked with Kozo Sugiyama and others on the research and development of graph drawing and idea support tools. In 2004, he moved to the University of Tsukuba. He has been involved in the development of visualization methods not only for graph drawing but also for various types of data. In 2021, he published "Introduction to Information Visualization (Japanese)," which organized the knowledge he had collected so far.
Accepted Papers

Andrew Suk and Ji Zeng. Unavoidable patterns in complete simple topological graphs

Steven Chaplick, Philipp Kindermann, Jonathan Klawitter, Ignaz Rutter and Alexander Wolff. Morphing Rectangular Duals

Therese Biedl. Visibility representations of toroidal and Kleinbottle graphs

Jacob Fox, Janos Pach and Andrew Suk. Quasiplanar graphs, string graphs, and the ErdősGallai problem

Sabine Cornelsen and Gregor Diatzko. Planar Confluent Orthogonal Drawings of 4Modal Digraphs

Grzegorz Gutowski, Florian Mittelstädt, Ignaz Rutter, Joachim Spoerhase, Alexander Wolff and Johannes Zink. Coloring Mixed and Directional Interval Graphs

Rosna Paul, Oswin Aichholzer, Kristin Knorr, Birgit Vogtenhuber, Johannes Obenaus, Wolfgang Mulzer, Nicolas El Maalouly, Meghana M Reddy and Alexandra Weinberger. Compatible Spanning Trees in Simple Drawings of $K_n$

Soeren Nickel, Martin Nöllenburg, Manuel Sorge, Anaïs Villedieu, HsiangYun Wu and Jules Wulms. Planarizing Graphs and their Drawings by Vertex Splitting

Steven Chaplick, Emilio Di Giacomo, Fabrizio Frati, Robert Ganian, Chrysanthi Raftopoulou and Kirill Simonov. Testing Upward Planarity of Partial 2Trees

Velitchko Filipov, Alessio Arleo, Markus Bögl and Silvia Miksch. On Time and Space: An Experimental Study on Graph Structural and Temporal Representations

Giuseppe Di Battista, Walter Didimo, Luca Grilli, Fabrizio Grosso, Giacomo Ortali, Maurizio Patrignani and Alessandra Tappini. Small PointSets Supporting Graph Stories

Carla Binucci, Emilio Di Giacomo, William J. Lenhart, Giuseppe Liotta, Fabrizio Montecchiani, Martin Nöllenburg and Antonios Symvonis. On the Complexity of the Storyplan Problem

Oksana Firman, Philipp Kindermann, Jonathan Klawitter, Boris Klemz, Felix Klesen and Alexander Wolff. OutsideObstacle Representations with All Vertices on the Outer Face

Stefan Felsner, Sandro Roch and Manfred Scheucher. Arrangements of Pseudocircles: On Digons and Triangles

Sergey Pupyrev. Queue Layouts of TwoDimensional Posets

Carlos Alegría, Giordano Da Lozzo, Giuseppe Di Battista, Fabrizio Frati, Fabrizio Grosso and Maurizio Patrignani. Unitlength Rectangular Drawings of Graphs

Michael Bekos, Martin Gronemann, Fabrizio Montecchiani and Antonios Symvonis. StrictlyConvex Drawings of 3Connected Planar Graphs

Kathryn Gray, Mingwei Li, Abu Reyan Ahmed and Stephen Kobourov. Visualizing Evolving Trees

Vasileios Geladaris, Panagiotis Lionakis and Ioannis Tollis. Computing a Feedback Arc Set Using PageRank

Kazuo Misue. Improved Scheduling of Morphing Edge Drawing

Jacob Miller, Vahan Huroyan and Stephen Kobourov. Spherical Graph Drawing by Multidimensional Scaling

William Lenhart and Giuseppe Liotta. Mutual Witness Gabriel Drawings of Complete Bipartite Graphs

Amyra Meidiana, SeokHee Hong and Peter Eades. ShapeFaithful Graph Drawings

Michael Bekos, Giordano Da Lozzo, Fabrizio Frati, Martin Gronemann, Tamara Mchedlidze and Chrysanthi Raftopoulou. Recognizing DAGs with PageNumber 2 is NPcomplete

Carla Binucci, Walter Didimo and Maurizio Patrignani. stOrientations with Few Transitive Edges

Michael Bekos, Stefan Felsner, Philipp Kindermann, Stephen Kobourov, Jan Kratochvíl and Ignaz Rutter. The RiqueNumber of Graphs

Loann Giovannangeli, Frédéric Lalanne, Romain Giot and Romain Bourqui. FORBID: Fast Overlap Removal By Stochastic Gradient Descent for Graph Drawing

Alfredo Garcia, Javier Tejel, Birgit Vogtenhuber and Alexandra Weinberger. Empty Triangles in Generalized Twisted Drawings of K_n

Walter Didimo, Michael Kaufmann, Giuseppe Liotta and Giacomo Ortali. Rectilinear Planarity of Partial 2Trees

Oswin Aichholzer, Alfredo Garcia, Irene Parada, Birgit Vogtenhuber and Alexandra Weinberger. Shooting Stars in Simple Drawings of K_{m,n}

Otfried Cheong, Maximilian Pfister and Lena Schlipf. The thickness of fanplanar graphs is at most three

Reyan Ahmed, Stephen Kobourov and Myroslav Kryven. An FPT Algorithm for Bipartite Vertex Splitting
Accepted Posters
Onsite Posters
 Ryosuke Saga, Tomoki Yoshikawa and Tomoharu Nakashima. Edge Bundling by Densitybased Pathfinding Approach
Online Posters

Mykyta Shvets, Ehsan Moradi and Debajyoti Mondal. Visualizing NodeSpecific Hierarchies in Directed Networks

Simon van Wageningen and Tamara Mchedlidze. Can an ML Model plainly learn Planar Layouts?

Giuseppe Liotta, Maarten Loffler, Fabrizio Montecchiani, Alessandra Tappini and Soeren Terziadis. The Witness Unit Disk Representability Problem

David Trye, Mark Apperley and David Bainbridge. Aggregating Hypergraphs by Node Attributes