Demo Data from EDBT 2026 / reviewers in the wild / expert
Alex Ulmer
dblp:135/6431
· DBLP profile ↗
7ranked-venue papers
4as first author
3since 2021 · last 2024
0009-0008-3778-8184ORCID · corroborated
Domains — the database's venue-derived domains; a paper can count in several
Human-computer interaction and ubiquitous computing · 5 · 2 first-author · 1 since 2021Security and privacy · 4 · 2 first-author · 1 since 2021Graphics, computer vision, multimedia, augmented reality and games · 2 · 2 first-author · 2 since 2021
Expertise — from the expertise taxonomy: the topics of the expert's papers under the CCF categories. A weight counts papers with recency: 1 for a paper about the topic, 0.3 when the topic is its context, halved every five years.
| Computer graphics and multimedia
1 paper |
Visualization and visual analytics · 100% |
Topics — the 2 heaviest of 3, each with the papers that count most for it
| Topic | Weight | Papers | Last | Evidence papers |
|---|---|---|---|---|
Visualization and visual analytics › visual analytics › interactive visual analysis
progressive visual analytics |
0.8 | 1 | 2024 | A Survey on Progressive Visualization · IEEE Trans. Vis. Comput. Graph. 2024 |
Visualization and visual analytics › information visualization
large-scale data visualization |
0.2 | 1 | 2024 | A Survey on Progressive Visualization · IEEE Trans. Vis. Comput. Graph. 2024 |
Methods — techniques the papers use, named apart from their topics
taxonomy derivation · 0.8systematic literature survey · 0.8
| Year | Publication | Venue | Position |
|---|---|---|---|
| 2024 | A Survey on Progressive VisualizationabstractCurrently, growing data sources and long-running algorithms impede user attention and interaction with visual analytics applications. Progressive visualization (PV) and visual analytics (PVA) alleviate this problem by allowing immediate feedback and interaction with large datasets and complex computations, avoiding waiting for complete results by using partial results improving with time. Yet, creating a progressive visualization requires more effort than a regular visualization but also opens up new possibilities, such as steering the computations towards more relevant parts of the data, thus saving computational resources. However, there is currently no comprehensive overview of the design space for progressive visualization systems. We surveyed the related work of PV and derived a new taxonomy for progressive visualizations by systematically categorizing all PV publications that included visualizations with progressive features. Progressive visualizations can be categorized by well-known visualization taxonomies, but we also found that progressive visualizations can be distinguished by the way they manage their data processing, data domain, and visual update. Furthermore, we identified key properties such as uncertainty, steering, visual stability, and real-time processing that are significantly different with progressive applications. We also collected evaluation methodologies reported by the publications and conclude with statistical findings, research gaps, and open challenges. Alex Ulmer, Marco Angelini, Jean-Daniel Fekete, Jörn Kohlhammer, Thorsten May |
IEEE Trans. Vis. Comput. Graph. | 1 |
| 2022 | Visualization Of Class Activation Maps To Explain AI Classification Of Network Packet CapturesabstractThe classification of internet traffic has become increasingly important due to the rapid growth of today’s networks and application variety. The number of connections and the addition of new applications in our networks causes a vast amount of log data and complicates the search for common patterns by experts. Finding such patterns among specific classes of applications is necessary to fulfill various requirements in network analytics. Supervised deep learning methods learn features from raw data and achieve high accuracy in classification. However, these methods are very complex and are used as black-box models, which weakens the experts’ trust in these classifications. Moreover, by using them as a black-box, new knowledge cannot be obtained from the model predictions despite their excellent performance. Therefore, the explainability of the classifications is crucial. Besides increasing trust, the explanation can be used for model evaluation to gain new insights from the data and to improve the model. In this paper, we present a visual and interactive tool that combines the classification of network data with an explanation technique to form an interface between experts, algorithms, and data. Igor Cherepanov, Alex Ulmer, Jonathan Geraldi Joewono, Jörn Kohlhammer |
VizSec | 2 |
| 2021 | ProBGP: Progressive Visual Analytics of Live BGP UpdatesabstractAbstract The global routing network is the backbone of the Internet. However, it is quite vulnerable to attacks that cause major disruptions or routing manipulations. Prior related works have visualized routing path changes with node link diagrams, but it requires strong domain expertise to understand if a routing change between autonomous systems is suspicious. Geographic visualization has an advantage over conventional node‐link diagrams by helping uncover such suspicious routes as the user can immediately see if a path is the shortest path to the target or an unreasonable detour. In this paper, we present ProBGP, a web‐based progressive approach to visually analyze BGP update routes. We created a novel progressive data processing algorithm for the geographic approximation of autonomous systems and combined it with a progressively updating visualization. While the newest log data is continuously loaded, our approach also allows querying the entire log recordings since 1999. We present the usefulness of our approach with a real use case of a major route leak from June 2019. We report on multiple interviews with domain experts throughout the development. Finally, we evaluated our algorithm quantitatively against a public peering database and qualitatively against AS network maps. Alex Ulmer, David Sessler, Jörn Kohlhammer |
Comput. Graph. Forum | 1 |
| 2019 | NetCapVis: Web-based Progressive Visual Analytics for Network Packet CapturesabstractNetwork traffic log data is a key data source for forensic analysis of cybersecurity incidents. Packet Captures (PCAPs) are the raw information directly gathered from the network device. As the bandwidth and connections to other hosts rise, this data becomes very large quickly. Malware analysts and administrators are using this data frequently for their analysis. However, the currently most used tool Wireshark is displaying the data as a table, making it difficult to get an overview and focus on the significant parts. Also, the process of loading large files into Wireshark takes time and has to be repeated each time the file is closed. We believe that this problem poses an optimal setting for a client-server infrastructure with a progressive visual analytics approach. The processing can be outsourced to the server while the client is progressively updated. In this paper we present NetCapVis, an web-based progressive visual analytics system where the user can upload PCAP files, set initial filters to reduce the data before uploading and then instantly interact with the data while the rest is progressively loaded into the visualizations. Alex Ulmer, David Sessler, Jörn Kohlhammer |
VizSEC | 1 |
| 2018 | Visual-Interactive Identification of Anomalous IP-Block Behavior Using Geo-IP DataabstractRouting of network packets from one computer to another is the backbone of the internet and impacts the everyday life of many people. Although, this is a fully automated process it has many security issues. IP hijacks and misconfigurations occur very often and are difficult to detect. In the past visual analytics approaches aimed at detecting these phenomenons but only a few of these integrated geographical references. Geo-IP data is being used mostly as a lookup table which is an undervaluation of its capabilities. In this paper we present a visual-interactive system which only relies on Geo-IP data to create more awareness for this data source. We show that looking at Geo-IP data over time in combination with owner and location information of IP blocks already reveals suspicious cases. Together with our design study we also contribute a pre-processing algorithm for the Maxmind GeoIP2 City and ISP databases, to motivate the community to integrate this data source in future approaches. Alex Ulmer, Marija Schufrin, David Sessler, Jörn Kohlhammer |
VizSEC | 1 |
| 2016 | Supporting Collaborative Political Decision Making: An Interactive Policy Process Visualization SystemabstractThe process of political decision making is often complex and tedious. The policy process consists of multiple steps, most of them are highly iterative. In addition, different stakeholder groups are involved in political decision making and contribute to the process. A series of textual documents accompanies the process. Examples are official documents, discussions, scientific reports, external reviews, newspaper articles, or economic white papers. Experts from the political domain report that this plethora of textual documents often exceeds their ability to keep track of the entire policy process. We present PolicyLine, a visualization system that supports different stakeholder groups in overview-and-detail tasks for large sets of textual documents in the political decision making process. In a longitudinal design study conducted together with domain experts in political decision making, we identified missing analytical functionality on the basis of a problem and domain characterization. In an iterative design phase, we created PolicyLine in close collaboration with the domain experts. Finally, we present the results of three evaluation rounds, and reflect on our collaborative visualization system. Tobias Ruppert, Andreas Bannach, Jürgen Bernard, Hendrik Lücke-Tieke, Alex Ulmer, Jörn Kohlhammer |
VINCI | 5 |
| 2016 | Uncovering periodic network signals of cyber attacksabstractThis paper addresses the problem of detecting the presence of malware that leaveperiodictraces innetworktraffic. This characteristic behavior of malware was found to be surprisingly prevalent in a parallel study. To this end, we propose a visual analytics solution that supports both automatic detection and manual inspection of periodic signals hidden in network traffic. The detected periodic signals are visually verified in an overview using a circular graph and two stacked histograms as well as in detail using deep packet inspection. Our approach offers the capability to detect complex periodic patterns, but avoids the unverifiability issue often encountered in related work. The periodicity assumption imposed on malware behavior is a relatively weak assumption, but initial evaluations with a simulated scenario as well as a publicly available network capture demonstrate its applicability. Huynh Ngoc Anh, Wee Keong Ng, Alex Ulmer, Jörn Kohlhammer |
VizSEC | 3 |