@misc{MarweckiBaudisch2018, author = {Marwecki, Sebastian and Baudisch, Patrick}, title = {Scenograph}, series = {UIST '18: Proceedings of the 31st Annual ACM Symposium on User Interface Software and Technology}, journal = {UIST '18: Proceedings of the 31st Annual ACM Symposium on User Interface Software and Technology}, publisher = {Association for Computing Machinery}, address = {New York}, isbn = {978-1-4503-5948-1}, doi = {10.1145/3242587.3242648}, pages = {511 -- 520}, year = {2018}, abstract = {When developing a real-walking virtual reality experience, designers generally create virtual locations to fit a specific tracking volume. Unfortunately, this prevents the resulting experience from running on a smaller or differently shaped tracking volume. To address this, we present a software system called Scenograph. The core of Scenograph is a tracking volume-independent representation of real-walking experiences. Scenograph instantiates the experience to a tracking volume of given size and shape by splitting the locations into smaller ones while maintaining narrative structure. In our user study, participants' ratings of realism decreased significantly when existing techniques were used to map a 25m2 experience to 9m2 and an L-shaped 8m2 tracking volume. In contrast, ratings did not differ when Scenograph was used to instantiate the experience.}, language = {en} } @article{BrewkaEllmauthalerKernIsberneretal.2018, author = {Brewka, Gerhard and Ellmauthaler, Stefan and Kern-Isberner, Gabriele and Obermeier, Philipp and Ostrowski, Max and Romero, Javier and Schaub, Torsten H. and Schieweck, Steffen}, title = {Advanced solving technology for dynamic and reactive applications}, series = {K{\"u}nstliche Intelligenz}, volume = {32}, journal = {K{\"u}nstliche Intelligenz}, number = {2-3}, publisher = {Springer}, address = {Heidelberg}, issn = {0933-1875}, doi = {10.1007/s13218-018-0538-8}, pages = {199 -- 200}, year = {2018}, language = {en} } @misc{KliemeTietzMeinel2018, author = {Klieme, Eric and Tietz, Christian and Meinel, Christoph}, title = {Beware of SMOMBIES}, series = {The 17th IEEE International Conference on Trust, Security and Privacy in Computing and Communications (IEEE TrustCom 2018)/the 12th IEEE International Conference on Big Data Science and Engineering (IEEE BigDataSE 2018)}, journal = {The 17th IEEE International Conference on Trust, Security and Privacy in Computing and Communications (IEEE TrustCom 2018)/the 12th IEEE International Conference on Big Data Science and Engineering (IEEE BigDataSE 2018)}, publisher = {IEEE}, address = {New York}, isbn = {978-1-5386-4387-7}, issn = {2324-9013}, doi = {10.1109/TrustCom/BigDataSE.2018.00096}, pages = {651 -- 660}, year = {2018}, abstract = {Several research evaluated the user's style of walking for the verification of a claimed identity and showed high authentication accuracies in many settings. In this paper we present a system that successfully verifies a user's identity based on many real world smartphone placements and yet not regarded interactions while walking. Our contribution is the distinction of all considered activities into three distinct subsets and a specific one-class Support Vector Machine per subset. Using sensor data of 30 participants collected in a semi-supervised study approach, we prove that unsupervised verification is possible with very low false-acceptance and false-rejection rates. We furthermore show that these subsets can be distinguished with a high accuracy and demonstrate that this system can be deployed on off-the-shelf smartphones.}, language = {en} } @inproceedings{KeilKonertDamniketal.2018, author = {Keil, Reinhard and Konert, Johannes and Damnik, Gregor and Gierl, Mark J. and Proske, Antje and K{\"o}rndle, Hermann and Narciss, Susanne and Wahl, Marina and H{\"o}lscher, Michael and Mariani, Ennio and Jaisli, Isabel and Tscherejkina, Anna and Morgiel, Anna and Moebert, Tobias and Herbstreit, Stephanie and M{\"a}ker, Daniela and Szalai, Cynthia and Braun, Iris and Kapp, Felix and Hara, Tenshi C. and Kubica, Tommy and Stumpf, Sarah}, title = {E-Learning Symposium 2018}, editor = {Lucke, Ulrike and Strickroth, Sven}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, doi = {10.25932/publishup-42071}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-420711}, pages = {71}, year = {2018}, abstract = {In den vergangenen Jahren sind viele E-Learning-Innovationen entstanden. Einige davon wurden auf den vergangenen E-Learning Symposien der Universit{\"a}t Potsdam pr{\"a}sentiert: Das erste E-Learning Symposium im Jahr 2012 konzentrierte sich auf unterschiedliche M{\"o}glichkeiten der Studierendenaktivierung und Lehrgestaltung. Das Symposium 2014 r{\"u}ckte vor allem die Studierenden ins Zentrum der Aufmerksamkeit. Im Jahr 2016 kam es durch das Zusammengehen des Symposiums mit der DeLFI-Tagung zu einer Fokussierung auf technische Innovationen. Doch was ist aus den Leuchtt{\"u}rmen von gestern geworden, und brauchen wir {\"u}berhaupt noch neue Leuchtt{\"u}rme? Das Symposium setzt sich in diesem Jahr unter dem Motto „Innovation und Nachhaltigkeit - (k)ein Gegensatz?" mit mediengest{\"u}tzten Lehr- und Lernprozessen im universit{\"a}ren Kontext auseinander und reflektiert aktuelle technische sowie didaktische Entwicklungen mit Blick auf deren mittel- bis langfristigen Einsatz in der Praxis. Dieser Tagungsband zum E-Learning Symposium 2018 an der Universit{\"a}t Potsdam beinhaltet eine Mischung von Forschungs- und Praxisbeitr{\"a}gen aus verschiedenen Fachdisziplinen und er{\"o}ffnet vielschichtige Perspektiven auf das Thema E-Learning. Dabei werden die Vielfalt der didaktischen Einsatzszenarien als auch die Potentiale von Werk-zeugen und Methoden der Informatik in ihrem Zusammenspiel beleuchtet. In seiner Keynote widmet sich Reinhard Keil dem Motto des Symposiums und geht der Nachhaltigkeit bei E-Learning-Projekten auf den Grund. Dabei analysiert und beleuchtet er anhand seiner {\"u}ber 15-j{\"a}hrigen Forschungspraxis die wichtigsten Wirkfaktoren und formuliert Empfehlungen zur Konzeption von E-Learning-Projekten. Im Gegensatz zu rein auf Kostenersparnis ausgerichteten (hochschul-)politischen Forderungen proklamiert er den Ansatz der hypothesengeleiteten Technikgestaltung, in der Nachhaltigkeit als Leitfrage oder Forschungsstrategie verstanden werden kann. In eine {\"a}hnliche Richtung geht der Beitrag von Iris Braun et al., die {\"u}ber Erfolgsfaktoren beim Einsatz von Audience Response Systemen in der universit{\"a}ren Lehre berichten. Ein weiteres aktuelles Thema, sowohl f{\"u}r die Bildungstechnologie als auch in den Bildungswissenschaften allgemein, ist die Kompetenzorientierung und -modellierung. Hier geht es darum (Probleml{\"o}se-)F{\"a}higkeiten gezielt zu beschreiben und in den Mittelpunkt der Lehre zu stellen. Johannes Konert stellt in einem eingeladenen Vortrag zwei Projekte vor, die den Prozess beginnend bei der Definition von Kompetenzen, deren Modellierung in einem semantischen maschinenlesbaren Format bis hin zur Erarbeitung von Methoden zur Kompetenzmessung und der elektronischen Zertifizierung aufzeigen. Dabei geht er auf technische M{\"o}glichkeiten, aber auch Grenzen ein. Auf einer spezifischeren Ebene besch{\"a}ftigt sich Sarah Stumpf mit digitalen bzw. mediendidaktischen Kompetenzen im Lehramtsstudium und stellt ein Framework f{\"u}r die F{\"o}rderung ebensolcher Kompetenzen bei angehenden Lehrkr{\"a}ften vor. Der Einsatz von E-Learning birgt noch einige Herausforderungen. Dabei geht es oft um die Verbindung von Didaktik und Technik, den Erhalt von Aufmerksamkeit oder den Aufwand f{\"u}r das Erstellen von interaktiven Lehr- und Lerninhalten. Drei Beitr{\"a}ge in diesem Tagungsband besch{\"a}ftigen sich mit dieser Thematik in unterschiedlichen Kontexten und zeigen Best-Practices und L{\"o}sungsans{\"a}tze auf: Der Beitrag von Martina Wahl und Michael H{\"o}lscher behandelt den besonderen Kontext von Blended Learning-Szenarien in berufsbegleitenden Studieng{\"a}ngen. Um die Ver{\"o}ffentlichung eines global frei verf{\"u}gbaren Onlinekurses abseits der großen MOOC Plattformen und den didaktischen Herausforderungen auch hinsichtlich der Motivation geht es im Beitrag von Ennio Marani und Isabel Jaisli. Schließlich schlagen Gregor Damnik et al. die automatische Erzeugung von Aufgaben zur Erh{\"o}hung von Interaktivit{\"a}t und Adaptivit{\"a}t in digitalen Lernressourcen vor, um den teilweise erheblichen Erstellungsaufwand zu reduzieren. Zum Thema E-Learning z{\"a}hlen auch immer mobile Apps bzw. Spiele. Gleich zwei Beitr{\"a}ge besch{\"a}ftigen sich mit dem Einsatz von E-Learning-Tools im Gesundheitskontext: Anna Tscherejkina und Anna Morgiel stellen in ihrem Beitrag Minispiele zum Training von sozio-emotionalen Kompetenzen f{\"u}r Menschen mit Autismus vor, und Stephanie Herbstreit et al. berichten vom Einsatz einer mobilen Lern-App zur Verbesserung von klinisch-praktischem Unterricht.}, language = {de} } @inproceedings{SeegererRomeikeTillmannetal.2018, author = {Seegerer, Stefan and Romeike, Ralf and Tillmann, Alexander and Kr{\"o}mker, Detlef and Horn, Florian and Gattinger, Thorsten and Weicker, Karsten and Schmitz, Dennis and Moldt, Daniel and R{\"o}pke, Ren{\´e} and Larisch, Kathrin and Schroeder, Ulrik and Keverp{\"u}tz, Claudia and K{\"u}ppers, Bastian and Striewe, Michael and Kramer, Matthias and Grillenberger, Andreas and Frede, Christiane and Knobelsdorf, Maria and Greven, Christoph}, title = {Hochschuldidaktik der Informatik HDI 2018}, series = {Commentarii informaticae didacticae (CID)}, booktitle = {Commentarii informaticae didacticae (CID)}, number = {12}, editor = {Bergner, Nadine and R{\"o}pke, Ren{\´e} and Schroeder, Ulrik and Kr{\"o}mker, Detlef}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, isbn = {978-3-86956-435-7}, issn = {1868-0844}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-413542}, pages = {161}, year = {2018}, abstract = {Die 8. Fachtagung f{\"u}r Hochschuldidaktik der Informatik (HDI) fand im September 2018 zusammen mit der Deutschen E-Learning Fachtagung Informatik (DeLFI) unter dem gemeinsamen Motto „Digitalisierungswahnsinn? - Wege der Bildungstransformationen" in Frankfurt statt. Dabei widmet sich die HDI allen Fragen der informatischen Bildung im Hochschulbereich. Schwerpunkte bildeten in diesem Jahr u. a.: - Analyse der Inhalte und anzustrebenden Kompetenzen in Informatikveranstaltungen - Programmieren lernen \& Einstieg in Softwareentwicklung - Spezialthemen: Data Science, Theoretische Informatik und Wissenschaftliches Arbeiten Die Fachtagung widmet sich ausgew{\"a}hlten Fragestellungen dieser Themenkomplexe, die durch Vortr{\"a}ge ausgewiesener Experten und durch eingereichte Beitr{\"a}ge intensiv behandelt werden.}, language = {de} } @article{LiChenNofaletal.2018, author = {Li, Yuanqing and Chen, Li and Nofal, Issam and Chen, Mo and Wang, Haibin and Liu, Rui and Chen, Qingyu and Krstić, Miloš and Shi, Shuting and Guo, Gang and Baeg, Sang H. and Wen, Shi-Jie and Wong, Richard}, title = {Modeling and analysis of single-event transient sensitivity of a 65 nm clock tree}, series = {Microelectronics reliability}, volume = {87}, journal = {Microelectronics reliability}, publisher = {Elsevier}, address = {Oxford}, issn = {0026-2714}, doi = {10.1016/j.microrel.2018.05.016}, pages = {24 -- 32}, year = {2018}, abstract = {The soft error rate (SER) due to heavy-ion irradiation of a clock tree is investigated in this paper. A method for clock tree SER prediction is developed, which employs a dedicated soft error analysis tool to characterize the single-event transient (SET) sensitivities of clock inverters and other commercial tools to calculate the SER through fault-injection simulations. A test circuit including a flip-flop chain and clock tree in a 65 nm CMOS technology is developed through the automatic ASIC design flow. This circuit is analyzed with the developed method to calculate its clock tree SER. In addition, this circuit is implemented in a 65 nm test chip and irradiated by heavy ions to measure its SER resulting from the SETs in the clock tree. The experimental and calculation results of this case study present good correlation, which verifies the effectiveness of the developed method.}, language = {en} } @misc{KrstićJentzsch2018, author = {Krstić, Miloš and Jentzsch, Anne-Kristin}, title = {Reliability, safety and security of the electronics in automated driving vehicles - joint lab lecturing approach}, series = {2018 12TH European Workshop on Microelectronics Education (EWME)}, journal = {2018 12TH European Workshop on Microelectronics Education (EWME)}, publisher = {IEEE}, address = {New York}, isbn = {978-1-5386-1157-9}, pages = {21 -- 22}, year = {2018}, abstract = {This paper proposes an education approach for master and bachelor students to enhance their skills in the area of reliability, safety and security of the electronic components in automated driving. The approach is based on the active synergetic work of research institutes, academia and industry in the frame of joint lab. As an example, the jointly organized summer school with the respective focus is organized and elaborated.}, language = {en} } @misc{BosserCabalarDieguezetal.2018, author = {Bosser, Anne-Gwenn and Cabalar, Pedro and Dieguez, Martin and Schaub, Torsten H.}, title = {Introducing temporal stable models for linear dynamic logic}, series = {16th International Conference on Principles of Knowledge Representation and Reasoning}, journal = {16th International Conference on Principles of Knowledge Representation and Reasoning}, publisher = {ASSOC Association for the Advancement of Artificial Intelligence}, address = {Palo Alto}, pages = {12 -- 21}, year = {2018}, abstract = {We propose a new temporal extension of the logic of Here-and-There (HT) and its equilibria obtained by combining it with dynamic logic over (linear) traces. Unlike previous temporal extensions of HT based on linear temporal logic, the dynamic logic features allow us to reason about the composition of actions. For instance, this can be used to exercise fine grained control when planning in robotics, as exemplified by GOLOG. In this paper, we lay the foundations of our approach, and refer to it as Linear Dynamic Equilibrium Logic, or simply DEL. We start by developing the formal framework of DEL and provide relevant characteristic results. Among them, we elaborate upon the relationships to traditional linear dynamic logic and previous temporal extensions of HT.}, language = {en} } @article{PrasseKnaebelMachlicaetal.2019, author = {Prasse, Paul and Knaebel, Rene and Machlica, Lukas and Pevny, Tomas and Scheffer, Tobias}, title = {Joint detection of malicious domains and infected clients}, series = {Machine learning}, volume = {108}, journal = {Machine learning}, number = {8-9}, publisher = {Springer}, address = {Dordrecht}, issn = {0885-6125}, doi = {10.1007/s10994-019-05789-z}, pages = {1353 -- 1368}, year = {2019}, abstract = {Detection of malware-infected computers and detection of malicious web domains based on their encrypted HTTPS traffic are challenging problems, because only addresses, timestamps, and data volumes are observable. The detection problems are coupled, because infected clients tend to interact with malicious domains. Traffic data can be collected at a large scale, and antivirus tools can be used to identify infected clients in retrospect. Domains, by contrast, have to be labeled individually after forensic analysis. We explore transfer learning based on sluice networks; this allows the detection models to bootstrap each other. In a large-scale experimental study, we find that the model outperforms known reference models and detects previously unknown malware, previously unknown malware families, and previously unknown malicious domains.}, language = {en} } @phdthesis{AbdelwahabHusseinAbdelwahabElsayed2019, author = {Abdelwahab Hussein Abdelwahab Elsayed, Ahmed}, title = {Probabilistic, deep, and metric learning for biometric identification from eye movements}, doi = {10.25932/publishup-46798}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-467980}, school = {Universit{\"a}t Potsdam}, pages = {vi, 65}, year = {2019}, abstract = {A central insight from psychological studies on human eye movements is that eye movement patterns are highly individually characteristic. They can, therefore, be used as a biometric feature, that is, subjects can be identified based on their eye movements. This thesis introduces new machine learning methods to identify subjects based on their eye movements while viewing arbitrary content. The thesis focuses on probabilistic modeling of the problem, which has yielded the best results in the most recent literature. The thesis studies the problem in three phases by proposing a purely probabilistic, probabilistic deep learning, and probabilistic deep metric learning approach. In the first phase, the thesis studies models that rely on psychological concepts about eye movements. Recent literature illustrates that individual-specific distributions of gaze patterns can be used to accurately identify individuals. In these studies, models were based on a simple parametric family of distributions. Such simple parametric models can be robustly estimated from sparse data, but have limited flexibility to capture the differences between individuals. Therefore, this thesis proposes a semiparametric model of gaze patterns that is flexible yet robust for individual identification. These patterns can be understood as domain knowledge derived from psychological literature. Fixations and saccades are examples of simple gaze patterns. The proposed semiparametric densities are drawn under a Gaussian process prior centered at a simple parametric distribution. Thus, the model will stay close to the parametric class of densities if little data is available, but it can also deviate from this class if enough data is available, increasing the flexibility of the model. The proposed method is evaluated on a large-scale dataset, showing significant improvements over the state-of-the-art. Later, the thesis replaces the model based on gaze patterns derived from psychological concepts with a deep neural network that can learn more informative and complex patterns from raw eye movement data. As previous work has shown that the distribution of these patterns across a sequence is informative, a novel statistical aggregation layer called the quantile layer is introduced. It explicitly fits the distribution of deep patterns learned directly from the raw eye movement data. The proposed deep learning approach is end-to-end learnable, such that the deep model learns to extract informative, short local patterns while the quantile layer learns to approximate the distributions of these patterns. Quantile layers are a generic approach that can converge to standard pooling layers or have a more detailed description of the features being pooled, depending on the problem. The proposed model is evaluated in a large-scale study using the eye movements of subjects viewing arbitrary visual input. The model improves upon the standard pooling layers and other statistical aggregation layers proposed in the literature. It also improves upon the state-of-the-art eye movement biometrics by a wide margin. Finally, for the model to identify any subject — not just the set of subjects it is trained on — a metric learning approach is developed. Metric learning learns a distance function over instances. The metric learning model maps the instances into a metric space, where sequences of the same individual are close, and sequences of different individuals are further apart. This thesis introduces a deep metric learning approach with distributional embeddings. The approach represents sequences as a set of continuous distributions in a metric space; to achieve this, a new loss function based on Wasserstein distances is introduced. The proposed method is evaluated on multiple domains besides eye movement biometrics. This approach outperforms the state of the art in deep metric learning in several domains while also outperforming the state of the art in eye movement biometrics.}, language = {en} }