@inproceedings{GruenerMuehleGayvoronskayaetal.2019, author = {Gr{\"u}ner, Andreas and M{\"u}hle, Alexander and Gayvoronskaya, Tatiana and Meinel, Christoph}, title = {A quantifiable trustmModel for Blockchain-based identity management}, series = {IEEE 2018 International Congress on Cybermatics / 2018 IEEE Conferences on Internet of Things, Green Computing and Communications, cyber, physical and Social Computing, Smart Data, Blockchain, Computer and Information Technology}, booktitle = {IEEE 2018 International Congress on Cybermatics / 2018 IEEE Conferences on Internet of Things, Green Computing and Communications, cyber, physical and Social Computing, Smart Data, Blockchain, Computer and Information Technology}, publisher = {IEEE}, address = {New York}, isbn = {978-1-5386-7975-3}, doi = {10.1109/Cybermatics_2018.2018.00250}, pages = {1475 -- 1482}, year = {2019}, language = {en} } @misc{HesseMatthiesSinzigetal.2019, author = {Hesse, G{\"u}nter and Matthies, Christoph and Sinzig, Werner and Uflacker, Matthias}, title = {Adding Value by Combining Business and Sensor Data}, series = {Database Systems for Advanced Applications}, volume = {11448}, journal = {Database Systems for Advanced Applications}, publisher = {Springer}, address = {Cham}, isbn = {978-3-030-18590-9}, issn = {0302-9743}, doi = {10.1007/978-3-030-18590-9_80}, pages = {528 -- 532}, year = {2019}, abstract = {Industry 4.0 and the Internet of Things are recent developments that have lead to the creation of new kinds of manufacturing data. Linking this new kind of sensor data to traditional business information is crucial for enterprises to take advantage of the data's full potential. In this paper, we present a demo which allows experiencing this data integration, both vertically between technical and business contexts and horizontally along the value chain. The tool simulates a manufacturing company, continuously producing both business and sensor data, and supports issuing ad-hoc queries that answer specific questions related to the business. In order to adapt to different environments, users can configure sensor characteristics to their needs.}, language = {en} } @misc{HernandezDemirayArnrichetal.2019, author = {Hernandez, Netzahualcoyotl and Demiray, Burcu and Arnrich, Bert and Favela, Jesus}, title = {An Exploratory Study to Detect Temporal Orientation Using Bluetooth's sensor}, series = {PervasiveHealth'19: Proceedings of the 13th EAI International Conference on Pervasive Computing Technologies for Healthcare}, journal = {PervasiveHealth'19: Proceedings of the 13th EAI International Conference on Pervasive Computing Technologies for Healthcare}, publisher = {Association for Computing Machinery}, address = {New York}, isbn = {978-1-4503-6126-2}, issn = {2153-1633}, doi = {10.1145/3329189.3329223}, pages = {292 -- 297}, year = {2019}, abstract = {Mobile sensing technology allows us to investigate human behaviour on a daily basis. In the study, we examined temporal orientation, which refers to the capacity of thinking or talking about personal events in the past and future. We utilise the mksense platform that allows us to use the experience-sampling method. Individual's thoughts and their relationship with smartphone's Bluetooth data is analysed to understand in which contexts people are influenced by social environments, such as the people they spend the most time with. As an exploratory study, we analyse social condition influence through a collection of Bluetooth data and survey information from participant's smartphones. Preliminary results show that people are likely to focus on past events when interacting with close-related people, and focus on future planning when interacting with strangers. Similarly, people experience present temporal orientation when accompanied by known people. We believe that these findings are linked to emotions since, in its most basic state, emotion is a state of physiological arousal combined with an appropriated cognition. In this contribution, we envision a smartphone application for automatically inferring human emotions based on user's temporal orientation by using Bluetooth sensors, we briefly elaborate on the influential factor of temporal orientation episodes and conclude with a discussion and lessons learned.}, language = {en} } @misc{PodlesnyKayemMeinel2019, author = {Podlesny, Nikolai Jannik and Kayem, Anne V. D. M. and Meinel, Christoph}, title = {Attribute Compartmentation and Greedy UCC Discovery for High-Dimensional Data Anonymisation}, series = {Proceedings of the Ninth ACM Conference on Data and Application Security and Privacy}, journal = {Proceedings of the Ninth ACM Conference on Data and Application Security and Privacy}, publisher = {Association for Computing Machinery}, address = {New York}, isbn = {978-1-4503-6099-9}, doi = {10.1145/3292006.3300019}, pages = {109 -- 119}, year = {2019}, abstract = {High-dimensional data is particularly useful for data analytics research. In the healthcare domain, for instance, high-dimensional data analytics has been used successfully for drug discovery. Yet, in order to adhere to privacy legislation, data analytics service providers must guarantee anonymity for data owners. In the context of high-dimensional data, ensuring privacy is challenging because increased data dimensionality must be matched by an exponential growth in the size of the data to avoid sparse datasets. Syntactically, anonymising sparse datasets with methods that rely of statistical significance, makes obtaining sound and reliable results, a challenge. As such, strong privacy is only achievable at the cost of high information loss, rendering the data unusable for data analytics. In this paper, we make two contributions to addressing this problem from both the privacy and information loss perspectives. First, we show that by identifying dependencies between attribute subsets we can eliminate privacy violating attributes from the anonymised dataset. Second, to minimise information loss, we employ a greedy search algorithm to determine and eliminate maximal partial unique attribute combinations. Thus, one only needs to find the minimal set of identifying attributes to prevent re-identification. Experiments on a health cloud based on the SAP HANA platform using a semi-synthetic medical history dataset comprised of 109 attributes, demonstrate the effectiveness of our approach.}, language = {en} } @misc{HerzogHoenigSchroederPreikschatetal.2019, author = {Herzog, Benedict and H{\"o}nig, Timo and Schr{\"o}der-Preikschat, Wolfgang and Plauth, Max and K{\"o}hler, Sven and Polze, Andreas}, title = {Bridging the Gap}, series = {e-Energy '19: Proceedings of the Tenth ACM International Conference on Future Energy Systems}, journal = {e-Energy '19: Proceedings of the Tenth ACM International Conference on Future Energy Systems}, publisher = {Association for Computing Machinery}, address = {New York}, isbn = {978-1-4503-6671-7}, doi = {10.1145/3307772.3330176}, pages = {428 -- 430}, year = {2019}, abstract = {The recent restructuring of the electricity grid (i.e., smart grid) introduces a number of challenges for today's large-scale computing systems. To operate reliable and efficient, computing systems must adhere not only to technical limits (i.e., thermal constraints) but they must also reduce operating costs, for example, by increasing their energy efficiency. Efforts to improve the energy efficiency, however, are often hampered by inflexible software components that hardly adapt to underlying hardware characteristics. In this paper, we propose an approach to bridge the gap between inflexible software and heterogeneous hardware architectures. Our proposal introduces adaptive software components that dynamically adapt to heterogeneous processing units (i.e., accelerators) during runtime to improve the energy efficiency of computing systems.}, language = {en} } @article{DischerRichterDoellner2019, author = {Discher, S{\"o}ren and Richter, Rico and D{\"o}llner, J{\"u}rgen Roland Friedrich}, title = {Concepts and techniques for web-based visualization and processing of massive 3D point clouds with semantics}, series = {Graphical Models}, volume = {104}, journal = {Graphical Models}, publisher = {Elsevier}, address = {San Diego}, issn = {1524-0703}, doi = {10.1016/j.gmod.2019.101036}, pages = {11}, year = {2019}, abstract = {3D point cloud technology facilitates the automated and highly detailed acquisition of real-world environments such as assets, sites, and countries. We present a web-based system for the interactive exploration and inspection of arbitrary large 3D point clouds. Our approach is able to render 3D point clouds with billions of points using spatial data structures and level-of-detail representations. Point-based rendering techniques and post-processing effects are provided to enable task-specific and data-specific filtering, e.g., based on semantics. A set of interaction techniques allows users to collaboratively work with the data (e.g., measuring distances and annotating). Additional value is provided by the system's ability to display additional, context-providing geodata alongside 3D point clouds and to integrate processing and analysis operations. We have evaluated the presented techniques and in case studies and with different data sets from aerial, mobile, and terrestrial acquisition with up to 120 billion points to show their practicality and feasibility.}, language = {en} } @article{vonSchorlemerWeiss2019, author = {von Schorlemer, Stephan and Weiß, Christian-Cornelius}, title = {data4life - Eine nutzerkontrollierte Gesundheitsdaten-Infrastruktu}, publisher = {Medizinisch Wissenschaftliche Verlagsgesellschaft}, address = {Berlin}, isbn = {978-3-95466-448-1}, pages = {249 -- 258}, year = {2019}, language = {de} } @misc{SeidelKrentzMeinel2019, author = {Seidel, Felix and Krentz, Konrad-Felix and Meinel, Christoph}, title = {Deep En-Route Filtering of Constrained Application Protocol (CoAP) Messages on 6LoWPAN Border Routers}, series = {2019 IEEE 5th World Forum on Internet of Things (WF-IoT)}, journal = {2019 IEEE 5th World Forum on Internet of Things (WF-IoT)}, publisher = {Institute of Electrical and Electronics Engineers}, address = {New York}, isbn = {978-1-5386-4980-0}, doi = {10.1109/WF-IoT.2019.8767262}, pages = {201 -- 206}, year = {2019}, abstract = {Devices on the Internet of Things (IoT) are usually battery-powered and have limited resources. Hence, energy-efficient and lightweight protocols were designed for IoT devices, such as the popular Constrained Application Protocol (CoAP). Yet, CoAP itself does not include any defenses against denial-of-sleep attacks, which are attacks that aim at depriving victim devices of entering low-power sleep modes. For example, a denial-of-sleep attack against an IoT device that runs a CoAP server is to send plenty of CoAP messages to it, thereby forcing the IoT device to expend energy for receiving and processing these CoAP messages. All current security solutions for CoAP, namely Datagram Transport Layer Security (DTLS), IPsec, and OSCORE, fail to prevent such attacks. To fill this gap, Seitz et al. proposed a method for filtering out inauthentic and replayed CoAP messages "en-route" on 6LoWPAN border routers. In this paper, we expand on Seitz et al.'s proposal in two ways. First, we revise Seitz et al.'s software architecture so that 6LoWPAN border routers can not only check the authenticity and freshness of CoAP messages, but can also perform a wide range of further checks. Second, we propose a couple of such further checks, which, as compared to Seitz et al.'s original checks, more reliably protect IoT devices that run CoAP servers from remote denial-of-sleep attacks, as well as from remote exploits. We prototyped our solution and successfully tested its compatibility with Contiki-NG's CoAP implementation.}, language = {en} } @book{OPUS4-51896, title = {Die Zukunft der Medizin}, editor = {B{\"o}ttinger, Erwin and zu Putlitz, Jasper}, publisher = {Medizinisch Wissenschaftliche Verlagsgesellschaft}, address = {Berlin}, isbn = {978-3-95466-398-9}, pages = {XIV, 414}, year = {2019}, abstract = {Die Medizin im 21. Jahrhundert wird sich so schnell ver{\"a}ndern wie nie zuvor - und mit ihr das Gesundheitswesen. Bahnbrechende Entwicklungen in Forschung und Digitalisierung werden die Auswertung und Nutzung riesiger Datenmengen in kurzer Zeit erm{\"o}glichen. Das wird unsere Kenntnisse {\"u}ber Gesundheit und gesund sein, sowie {\"u}ber die Entstehung, Pr{\"a}vention und Heilung von Krankheiten vollkommen ver{\"a}ndern. Gleichzeitig wird sich die Art und Weise, wie Medizin praktiziert wird, fundamental ver{\"a}ndern. Das Selbstverst{\"a}ndnis nahezu aller Akteure wird sich rasch weiterentwickeln m{\"u}ssen. Das Gesundheitssystem wird in allen Bereichen umgebaut und teilweise neu erfunden werden. Digitale Transformation, Personalisierung und Pr{\"a}vention sind die Treiber der neuen Medizin. Deutschland darf den Anschluss nicht verpassen. Im Vergleich mit anderen L{\"a}ndern ist das deutsche Gesundheitswesen in vielen Punkten bedrohlich r{\"u}ckst{\"a}ndig und fragmentiert. Um die Medizin und das Gesundheitswesen in Deutschland langfristig zukunftsfest zu machen, bedarf es vieler Anstrengungen - vor allem aber Offenheit gegen{\"u}ber Ver{\"a}nderungen, sowie einen regulatorischen Rahmen, der erm{\"o}glicht, dass die medizinischen und digitalen Innovationen beim Patienten ankommen. DIE ZUKUNFT DER MEDIZIN beschreibt Entwicklungen und Technologien, die die Medizin und das Gesundheitswesen im 21. Jahrhundert pr{\"a}gen werden. Das Buch informiert {\"u}ber die zum Teil dramatischen, disruptiven Innovationen in der Forschung, die durch Big Data, K{\"u}nstliche Intelligenz und Robotik m{\"o}glich werden. Die Autoren sind f{\"u}hrende Vordenker ihres Fachs und beschreiben aus langj{\"a}hriger Erfahrung im In- und Ausland zuk{\"u}nftige Entwicklungen, die jetzt bereits greifbar sind.}, language = {de} } @article{MeinelGayvoronskayaMuehle2019, author = {Meinel, Christoph and Gayvoronskaya, Tatiana and M{\"u}hle, Alexander}, title = {Die Zukunftspotenziale der Blockchain-Technologie}, series = {Die Zukunft der Medizin : disruptive Innovationen revolutionieren Medizin und Gesundheit}, journal = {Die Zukunft der Medizin : disruptive Innovationen revolutionieren Medizin und Gesundheit}, publisher = {Medizinisch Wissenschaftliche Verlagsgesellschaft}, address = {Berlin}, isbn = {978-3-95466-398-9}, pages = {259 -- 280}, year = {2019}, language = {de} } @article{YousfiWeske2019, author = {Yousfi, Alaaeddine and Weske, Mathias}, title = {Discovering commute patterns via process mining}, series = {Knowledge and Information Systems}, volume = {60}, journal = {Knowledge and Information Systems}, number = {2}, publisher = {Springer}, address = {London}, issn = {0219-1377}, doi = {10.1007/s10115-018-1255-1}, pages = {691 -- 713}, year = {2019}, abstract = {Ubiquitous computing has proven its relevance and efficiency in improving the user experience across a myriad of situations. It is now the ineluctable solution to keep pace with the ever-changing environments in which current systems operate. Despite the achievements of ubiquitous computing, this discipline is still overlooked in business process management. This is surprising, since many of today's challenges, in this domain, can be addressed by methods and techniques from ubiquitous computing, for instance user context and dynamic aspects of resource locations. This paper takes a first step to integrate methods and techniques from ubiquitous computing in business process management. To do so, we propose discovering commute patterns via process mining. Through our proposition, we can deduce the users' significant locations, routes, travel times and travel modes. This information can be a stepping-stone toward helping the business process management community embrace the latest achievements in ubiquitous computing, mainly in location-based service. To corroborate our claims, a user study was conducted. The significant places, routes, travel modes and commuting times of our test subjects were inferred with high accuracies. All in all, ubiquitous computing can enrich the processes with new capabilities that go beyond what has been established in business process management so far.}, language = {en} } @misc{BjoerkHoelze2019, author = {Bj{\"o}rk, Jennie and H{\"o}lze, Katharina}, title = {Editorial}, series = {Creativity and innovation management}, volume = {28}, journal = {Creativity and innovation management}, number = {3}, publisher = {Wiley}, address = {Hoboken}, issn = {0963-1690}, doi = {10.1111/caim.12336}, pages = {289 -- 290}, year = {2019}, language = {en} } @article{DrimallaLandwehrHessetal.2019, author = {Drimalla, Hanna and Landwehr, Niels and Hess, Ursula and Dziobek, Isabel}, title = {From face to face}, series = {Cognition and Emotion}, volume = {33}, journal = {Cognition and Emotion}, number = {8}, publisher = {Routledge, Taylor \& Francis Group}, address = {Abingdon}, issn = {0269-9931}, doi = {10.1080/02699931.2019.1596068}, pages = {1672 -- 1686}, year = {2019}, abstract = {Despite advances in the conceptualisation of facial mimicry, its role in the processing of social information is a matter of debate. In the present study, we investigated the relationship between mimicry and cognitive and emotional empathy. To assess mimicry, facial electromyography was recorded for 70 participants while they completed the Multifaceted Empathy Test, which presents complex context-embedded emotional expressions. As predicted, inter-individual differences in emotional and cognitive empathy were associated with the level of facial mimicry. For positive emotions, the intensity of the mimicry response scaled with the level of state emotional empathy. Mimicry was stronger for the emotional empathy task compared to the cognitive empathy task. The specific empathy condition could be successfully detected from facial muscle activity at the level of single individuals using machine learning techniques. These results support the view that mimicry occurs depending on the social context as a tool to affiliate and it is involved in cognitive as well as emotional empathy.}, language = {en} } @incollection{BauerMalchowMeinel2019, author = {Bauer, Matthias and Malchow, Martin and Meinel, Christoph}, title = {Full Lecture Recording Watching Behavior, or Why Students Watch 90-Min Lectures in 5 Min}, series = {IMCL 2018: Mobile Technologies and Applications for the Internet of Things}, volume = {909}, booktitle = {IMCL 2018: Mobile Technologies and Applications for the Internet of Things}, publisher = {Springer}, address = {Cham}, isbn = {978-3-030-11434-3}, issn = {2194-5357}, doi = {10.1007/978-3-030-11434-3_38}, pages = {347 -- 358}, year = {2019}, abstract = {Many universities record the lectures being held in their facilities to preserve knowledge and to make it available to their students and, at least for some universities and classes, to the broad public. The way with the least effort is to record the whole lecture, which in our case usually is 90 min long. This saves the labor and time of cutting and rearranging lectures scenes to provide short learning videos as known from Massive Open Online Courses (MOOCs), etc. Many lecturers fear that recording their lectures and providing them via an online platform might lead to less participation in the actual lecture. Also, many teachers fear that the lecture recordings are not used with the same focus and dedication as lectures in a lecture hall. In this work, we show that in our experience, full lectures have an average watching duration of just a few minutes and explain the reasons for that and why, in most cases, teachers do not have to worry about that.}, language = {en} } @misc{PerscheidUflacker2019, author = {Perscheid, Cindy and Uflacker, Matthias}, title = {Integrating Biological Context into the Analysis of Gene Expression Data}, series = {Distributed Computing and Artificial Intelligence, Special Sessions, 15th International Conference}, volume = {801}, journal = {Distributed Computing and Artificial Intelligence, Special Sessions, 15th International Conference}, publisher = {Springer}, address = {Cham}, isbn = {978-3-319-99608-0}, issn = {2194-5357}, doi = {10.1007/978-3-319-99608-0_41}, pages = {339 -- 343}, year = {2019}, abstract = {High-throughput RNA sequencing produces large gene expression datasets whose analysis leads to a better understanding of diseases like cancer. The nature of RNA-Seq data poses challenges to its analysis in terms of its high dimensionality, noise, and complexity of the underlying biological processes. Researchers apply traditional machine learning approaches, e. g. hierarchical clustering, to analyze this data. Until it comes to validation of the results, the analysis is based on the provided data only and completely misses the biological context. However, gene expression data follows particular patterns - the underlying biological processes. In our research, we aim to integrate the available biological knowledge earlier in the analysis process. We want to adapt state-of-the-art data mining algorithms to consider the biological context in their computations and deliver meaningful results for researchers.}, language = {en} } @misc{TrappDoellner2019, author = {Trapp, Matthias and D{\"o}llner, J{\"u}rgen Roland Friedrich}, title = {Interactive Close-Up Rendering for Detail plus Overview Visualization of 3D Digital Terrain Models}, series = {2019 23rd International Conference Information Visualisation (IV)}, journal = {2019 23rd International Conference Information Visualisation (IV)}, editor = {Banissi, E Ursyn}, publisher = {Inst. of Electr. and Electronics Engineers}, address = {Los Alamitos}, isbn = {978-1-7281-2838-2}, issn = {2375-0138}, doi = {10.1109/IV.2019.00053}, pages = {275 -- 280}, year = {2019}, abstract = {This paper presents an interactive rendering technique for detail+overview visualization of 3D digital terrain models using interactive close-ups. A close-up is an alternative presentation of input data varying with respect to geometrical scale, mapping, appearance, as well as Level-of-Detail (LOD) and Level-of-Abstraction (LOA) used. The presented 3D close-up approach enables in-situ comparison of multiple Regionof-Interests (ROIs) simultaneously. We describe a GPU-based rendering technique for the image-synthesis of multiple close-ups in real-time.}, language = {en} } @article{BaudischSilberKommanaetal.2019, author = {Baudisch, Patrick Markus and Silber, Arthur and Kommana, Yannis and Gruner, Milan and Wall, Ludwig and Reuss, Kevin and Heilman, Lukas and Kovacs, Robert and Rechlitz, Daniel and Roumen, Thijs}, title = {Kyub}, series = {Proceedings of the 2019 CHI Conference on Human Factors in Computing Systems}, journal = {Proceedings of the 2019 CHI Conference on Human Factors in Computing Systems}, publisher = {Association for Computing Machinery}, address = {New York}, isbn = {978-1-4503-5970-2}, doi = {10.1145/3290605.3300796}, pages = {1 -- 12}, year = {2019}, abstract = {We present an interactive editing system for laser cutting called kyub. Kyub allows users to create models efficiently in 3D, which it then unfolds into the 2D plates laser cutters expect. Unlike earlier systems, such as FlatFitFab, kyub affords construction based on closed box structures, which allows users to turn very thin material, such as 4mm plywood, into objects capable of withstanding large forces, such as chairs users can actually sit on. To afford such sturdy construction, every kyub project begins with a simple finger-joint "boxel"-a structure we found to be capable of withstanding over 500kg of load. Users then extend their model by attaching additional boxels. Boxels merge automatically, resulting in larger, yet equally strong structures. While the concept of stacking boxels allows kyub to offer the strong affordance and ease of use of a voxel-based editor, boxels are not confined to a grid and readily combine with kuyb's various geometry deformation tools. In our technical evaluation, objects built with kyub withstood hundreds of kilograms of loads. In our user study, non-engineers rated the learnability of kyub 6.1/7.}, language = {en} } @misc{BartzYangBethgeetal.2019, author = {Bartz, Christian and Yang, Haojin and Bethge, Joseph and Meinel, Christoph}, title = {LoANs}, series = {Computer Vision - ACCV 2018 Workshops}, volume = {11367}, journal = {Computer Vision - ACCV 2018 Workshops}, publisher = {Springer}, address = {Cham}, isbn = {978-3-030-21074-8}, issn = {0302-9743}, doi = {10.1007/978-3-030-21074-8_29}, pages = {341 -- 356}, year = {2019}, abstract = {Recently, deep neural networks have achieved remarkable performance on the task of object detection and recognition. The reason for this success is mainly grounded in the availability of large scale, fully annotated datasets, but the creation of such a dataset is a complicated and costly task. In this paper, we propose a novel method for weakly supervised object detection that simplifies the process of gathering data for training an object detector. We train an ensemble of two models that work together in a student-teacher fashion. Our student (localizer) is a model that learns to localize an object, the teacher (assessor) assesses the quality of the localization and provides feedback to the student. The student uses this feedback to learn how to localize objects and is thus entirely supervised by the teacher, as we are using no labels for training the localizer. In our experiments, we show that our model is very robust to noise and reaches competitive performance compared to a state-of-the-art fully supervised approach. We also show the simplicity of creating a new dataset, based on a few videos (e.g. downloaded from YouTube) and artificially generated data.}, language = {en} } @misc{MarweckiWilsonOfeketal.2019, author = {Marwecki, Sebastian and Wilson, Andrew D. and Ofek, Eyal and Franco, Mar Gonzalez and Holz, Christian}, title = {Mise-Unseen}, series = {UIST '19: Proceedings of the 32nd Annual ACM Symposium on User Interface Software and Technology}, journal = {UIST '19: Proceedings of the 32nd Annual ACM Symposium on User Interface Software and Technology}, publisher = {Association for Computing Machinery}, address = {New York}, isbn = {978-1-4503-6816-2}, doi = {10.1145/3332165.3347919}, pages = {777 -- 789}, year = {2019}, abstract = {Creating or arranging objects at runtime is needed in many virtual reality applications, but such changes are noticed when they occur inside the user's field of view. We present Mise-Unseen, a software system that applies such scene changes covertly inside the user's field of view. Mise-Unseen leverages gaze tracking to create models of user attention, intention, and spatial memory to determine if and when to inject a change. We present seven applications of Mise-Unseen to unnoticeably modify the scene within view (i) to hide that task difficulty is adapted to the user, (ii) to adapt the experience to the user's preferences, (iii) to time the use of low fidelity effects, (iv) to detect user choice for passive haptics even when lacking physical props, (v) to sustain physical locomotion despite a lack of physical space, (vi) to reduce motion sickness during virtual locomotion, and (vii) to verify user understanding during story progression. We evaluated Mise-Unseen and our applications in a user study with 15 participants and find that while gaze data indeed supports obfuscating changes inside the field of view, a change is rendered unnoticeably by using gaze in combination with common masking techniques.}, language = {en} } @article{HehnMendezUebernickeletal.2019, author = {Hehn, Jennifer and Mendez, Daniel and Uebernickel, Falk and Brenner, Walter and Broy, Manfred}, title = {On integrating design thinking for human-centered requirements engineering}, series = {IEEE software}, volume = {37}, journal = {IEEE software}, number = {2}, publisher = {Inst. of Electr. and Electronics Engineers}, address = {Los Alamitos}, issn = {0740-7459}, doi = {10.1109/MS.2019.2957715}, pages = {25 -- 31}, year = {2019}, abstract = {We elaborate on the possibilities and needs to integrate design thinking into requirements engineering, drawing from our research and project experiences. We suggest three approaches for tailoring and integrating design thinking and requirements engineering with complementary synergies and point at open challenges for research and practice.}, language = {en} } @article{BiloLenzner2019, author = {Bil{\`o}, Davide and Lenzner, Pascal}, title = {On the tree conjecture for the network creation game}, series = {Theory of computing systems}, volume = {64}, journal = {Theory of computing systems}, number = {3}, publisher = {Springer}, address = {New York}, issn = {1432-4350}, doi = {10.1007/s00224-019-09945-9}, pages = {422 -- 443}, year = {2019}, abstract = {Selfish Network Creation focuses on modeling real world networks from a game-theoretic point of view. One of the classic models by Fabrikant et al. (2003) is the network creation game, where agents correspond to nodes in a network which buy incident edges for the price of alpha per edge to minimize their total distance to all other nodes. The model is well-studied but still has intriguing open problems. The most famous conjectures state that the price of anarchy is constant for all alpha and that for alpha >= n all equilibrium networks are trees. We introduce a novel technique for analyzing stable networks for high edge-price alpha and employ it to improve on the best known bound for the latter conjecture. In particular we show that for alpha > 4n - 13 all equilibrium networks must be trees, which implies a constant price of anarchy for this range of alpha. Moreover, we also improve the constant upper bound on the price of anarchy for equilibrium trees.}, language = {en} } @misc{GhahremaniGiese2019, author = {Ghahremani, Sona and Giese, Holger}, title = {Performance evaluation for self-healing systems}, series = {2019 IEEE 4th International Workshops on Foundations and Applications of Self* Systems (FAS*W)}, journal = {2019 IEEE 4th International Workshops on Foundations and Applications of Self* Systems (FAS*W)}, publisher = {IEEE}, address = {New York}, isbn = {978-1-7281-2406-3}, doi = {10.1109/FAS-W.2019.00039}, pages = {116 -- 119}, year = {2019}, abstract = {Evaluating the performance of self-adaptive systems (SAS) is challenging due to their complexity and interaction with the often highly dynamic environment. In the context of self-healing systems (SHS), employing simulators has been shown to be the most dominant means for performance evaluation. Simulating a SHS also requires realistic fault injection scenarios. We study the state of the practice for evaluating the performance of SHS by means of a systematic literature review. We present the current practice and point out that a more thorough and careful treatment in evaluating the performance of SHS is required.}, language = {en} } @misc{TrappDoellner2019, author = {Trapp, Matthias and D{\"o}llner, J{\"u}rgen Roland Friedrich}, title = {Real-time Screen-space Geometry Draping for 3D Digital Terrain Models}, series = {2019 23rd International Conference Information Visualisation (IV)}, journal = {2019 23rd International Conference Information Visualisation (IV)}, publisher = {Inst. of Electr. and Electronics Engineers}, address = {Los Alamitos}, isbn = {978-1-7281-2838-2}, issn = {2375-0138}, doi = {10.1109/IV.2019.00054}, pages = {281 -- 286}, year = {2019}, abstract = {A fundamental task in 3D geovisualization and GIS applications is the visualization of vector data that can represent features such as transportation networks or land use coverage. Mapping or draping vector data represented by geometric primitives (e.g., polylines or polygons) to 3D digital elevation or 3D digital terrain models is a challenging task. We present an interactive GPU-based approach that performs geometry-based draping of vector data on per-frame basis using an image-based representation of a 3D digital elevation or terrain model only.}, language = {en} } @misc{FlorioTrappDoellner2019, author = {Florio, Alessandro and Trapp, Matthias and D{\"o}llner, J{\"u}rgen Roland Friedrich}, title = {Semantic-driven Visualization Techniques for Interactive Exploration of 3D Indoor Models}, series = {2019 23rd International Conference Information Visualisation (IV)}, journal = {2019 23rd International Conference Information Visualisation (IV)}, publisher = {Inst. of Electr. and Electronics Engineers}, address = {Los Alamitos}, isbn = {978-1-7281-2838-2}, issn = {2375-0138}, doi = {10.1109/IV.2019.00014}, pages = {25 -- 30}, year = {2019}, abstract = {The availability of detailed virtual 3D building models including representations of indoor elements, allows for a wide number of applications requiring effective exploration and navigation functionality. Depending on the application context, users should be enabled to focus on specific Objects-of-Interests (OOIs) or important building elements. This requires approaches to filtering building parts as well as techniques to visualize important building objects and their relations. For it, this paper explores the application and combination of interactive rendering techniques as well as their semanticallydriven configuration in the context of 3D indoor models.}, language = {en} } @misc{Giese2019, author = {Giese, Holger Burkhard}, title = {Software Engineering for Smart Cyber-Physical Systems}, series = {Proceedings of the 12th Innovations on Software Engineering Conference}, journal = {Proceedings of the 12th Innovations on Software Engineering Conference}, publisher = {Association for Computing Machinery}, address = {New York}, isbn = {978-1-4503-6215-3}, doi = {10.1145/3299771.3301650}, pages = {1}, year = {2019}, abstract = {Currently, a transformation of our technical world into a networked technical world where besides the embedded systems with their interaction with the physical world the interconnection of these nodes in the cyber world becomes a reality can be observed. In parallel nowadays there is a strong trend to employ artificial intelligence techniques and in particular machine learning to make software behave smart. Often cyber-physical systems must be self-adaptive at the level of the individual systems to operate as elements in open, dynamic, and deviating overall structures and to adapt to open and dynamic contexts while being developed, operated, evolved, and governed independently. In this presentation, we will first discuss the envisioned future scenarios for cyber-physical systems with an emphasis on the synergies networking can offer and then characterize which challenges for the design, production, and operation of these systems result. We will then discuss to what extent our current capabilities, in particular concerning software engineering match these challenges and where substantial improvements for the software engineering are crucial. In today's software engineering for embedded systems models are used to plan systems upfront to maximize envisioned properties on the one hand and minimize cost on the other hand. When applying the same ideas to software for smart cyber-physical systems, it soon turned out that for these systems often somehow more subtle links between the involved models and the requirements, users, and environment exist. Self-adaptation and runtime models have been advocated as concepts to covers the demands that result from these subtler links. Lately, both trends have been brought together more thoroughly by the notion of self-aware computing systems. We will review the underlying causes, discuss some our work in this direction, and outline related open challenges and potential for future approaches to software engineering for smart cyber-physical systems.}, language = {en} } @misc{RoumenShigeyamaRudolphetal.2019, author = {Roumen, Thijs and Shigeyama, Jotaro and Rudolph, Julius Cosmo Romeo and Grzelka, Felix and Baudisch, Patrick}, title = {SpringFit}, series = {User Interface Software and Technology}, journal = {User Interface Software and Technology}, publisher = {Association for Computing Machinery}, address = {New York}, isbn = {978-1-4503-6816-2}, doi = {10.1145/3332165.3347930}, pages = {727 -- 738}, year = {2019}, abstract = {Joints are crucial to laser cutting as they allow making three-dimensional objects; mounts are crucial because they allow embedding technical components, such as motors. Unfortunately, mounts and joints tend to fail when trying to fabricate a model on a different laser cutter or from a different material. The reason for this lies in the way mounts and joints hold objects in place, which is by forcing them into slightly smaller openings. Such "press fit" mechanisms unfortunately are susceptible to the small changes in diameter that occur when switching to a machine that removes more or less material ("kerf"), as well as to changes in stiffness, as they occur when switching to a different material. We present a software tool called springFit that resolves this problem by replacing the problematic press fit-based mounts and joints with what we call cantilever-based mounts and joints. A cantilever spring is simply a long thin piece of material that pushes against the object to be held. Unlike press fits, cantilever springs are robust against variations in kerf and material; they can even handle very high variations, simply by using longer springs. SpringFit converts models in the form of 2D cutting plans by replacing all contained mounts, notch joints, finger joints, and t-joints. In our technical evaluation, we used springFit to convert 14 models downloaded from the web.}, language = {en} } @article{DraisbachChristenNaumann2019, author = {Draisbach, Uwe and Christen, Peter and Naumann, Felix}, title = {Transforming pairwise duplicates to entity clusters for high-quality duplicate detection}, series = {ACM Journal of Data and Information Quality}, volume = {12}, journal = {ACM Journal of Data and Information Quality}, number = {1}, publisher = {Association for Computing Machinery}, address = {New York}, issn = {1936-1955}, doi = {10.1145/3352591}, pages = {1 -- 30}, year = {2019}, abstract = {Duplicate detection algorithms produce clusters of database records, each cluster representing a single real-world entity. As most of these algorithms use pairwise comparisons, the resulting (transitive) clusters can be inconsistent: Not all records within a cluster are sufficiently similar to be classified as duplicate. Thus, one of many subsequent clustering algorithms can further improve the result.
We explain in detail, compare, and evaluate many of these algorithms and introduce three new clustering algorithms in the specific context of duplicate detection. Two of our three new algorithms use the structure of the input graph to create consistent clusters. Our third algorithm, and many other clustering algorithms, focus on the edge weights, instead. For evaluation, in contrast to related work, we experiment on true real-world datasets, and in addition examine in great detail various pair-selection strategies used in practice. While no overall winner emerges, we are able to identify best approaches for different situations. In scenarios with larger clusters, our proposed algorithm, Extended Maximum Clique Clustering (EMCC), and Markov Clustering show the best results. EMCC especially outperforms Markov Clustering regarding the precision of the results and additionally has the advantage that it can also be used in scenarios where edge weights are not available.}, language = {en} } @article{IonLindlbauerHerholzetal.2019, author = {Ion, Alexandra and Lindlbauer, David and Herholz, Philipp and Alexa, Marc and Baudisch, Patrick Markus}, title = {Understanding Metamaterial Mechanisms}, series = {Proceedings of the 2019 CHI Conference on Human Factors in Computing Systems}, journal = {Proceedings of the 2019 CHI Conference on Human Factors in Computing Systems}, publisher = {Association for Computing Machinery}, address = {New York}, isbn = {978-1-4503-5970-2}, doi = {10.1145/3290605.3300877}, pages = {14}, year = {2019}, abstract = {In this paper, we establish the underlying foundations of mechanisms that are composed of cell structures-known as metamaterial mechanisms. Such metamaterial mechanisms were previously shown to implement complete mechanisms in the cell structure of a 3D printed material, without the need for assembly. However, their design is highly challenging. A mechanism consists of many cells that are interconnected and impose constraints on each other. This leads to unobvious and non-linear behavior of the mechanism, which impedes user design. In this work, we investigate the underlying topological constraints of such cell structures and their influence on the resulting mechanism. Based on these findings, we contribute a computational design tool that automatically creates a metamaterial mechanism from user-defined motion paths. This tool is only feasible because our novel abstract representation of the global constraints highly reduces the search space of possible cell arrangements.}, language = {en} } @misc{SukmanaTorkuraGraupneretal.2019, author = {Sukmana, Muhammad Ihsan Haikal and Torkura, Kennedy A. and Graupner, Hendrik and Cheng, Feng and Meinel, Christoph}, title = {Unified Cloud Access Control Model for Cloud Storage Broker}, series = {33rd International Conference on Information Networking (ICOIN 2019)}, journal = {33rd International Conference on Information Networking (ICOIN 2019)}, publisher = {IEEE}, address = {Los Alamitos}, isbn = {978-1-5386-8350-7}, issn = {1976-7684}, doi = {10.1109/ICOIN.2019.8717982}, pages = {60 -- 65}, year = {2019}, abstract = {Cloud Storage Broker (CSB) provides value-added cloud storage service for enterprise usage by leveraging multi-cloud storage architecture. However, it raises several challenges for managing resources and its access control in multiple Cloud Service Providers (CSPs) for authorized CSB stakeholders. In this paper we propose unified cloud access control model that provides the abstraction of CSP's services for centralized and automated cloud resource and access control management in multiple CSPs. Our proposal offers role-based access control for CSB stakeholders to access cloud resources by assigning necessary privileges and access control list for cloud resources and CSB stakeholders, respectively, following privilege separation concept and least privilege principle. We implement our unified model in a CSB system called CloudRAID for Business (CfB) with the evaluation result shows it provides system-and-cloud level security service for cfB and centralized resource and access control management in multiple CSPs.}, language = {en} } @article{LeopoldvanderAaOffenbergetal.2019, author = {Leopold, Henrik and van der Aa, Han and Offenberg, Jelmer and Reijers, Hajo A.}, title = {Using Hidden Markov Models for the accurate linguistic analysis of process model activity labels}, series = {Information systems}, volume = {83}, journal = {Information systems}, publisher = {Elsevier}, address = {Oxford}, issn = {0306-4379}, doi = {10.1016/j.is.2019.02.005}, pages = {30 -- 39}, year = {2019}, abstract = {Many process model analysis techniques rely on the accurate analysis of the natural language contents captured in the models' activity labels. Since these labels are typically short and diverse in terms of their grammatical style, standard natural language processing tools are not suitable to analyze them. While a dedicated technique for the analysis of process model activity labels was proposed in the past, it suffers from considerable limitations. First of all, its performance varies greatly among data sets with different characteristics and it cannot handle uncommon grammatical styles. What is more, adapting the technique requires in-depth domain knowledge. We use this paper to propose a machine learning-based technique for activity label analysis that overcomes the issues associated with this rule-based state of the art. Our technique conceptualizes activity label analysis as a tagging task based on a Hidden Markov Model. By doing so, the analysis of activity labels no longer requires the manual specification of rules. An evaluation using a collection of 15,000 activity labels demonstrates that our machine learning-based technique outperforms the state of the art in all aspects.}, language = {en} } @misc{SianiparWillemsMeinel2019, author = {Sianipar, Johannes Harungguan and Willems, Christian and Meinel, Christoph}, title = {Virtual machine integrity verification in Crowd-Resourcing Virtual Laboratory}, series = {2018 IEEE 11th Conference on Service-Oriented Computing and Applications (SOCA)}, journal = {2018 IEEE 11th Conference on Service-Oriented Computing and Applications (SOCA)}, publisher = {IEEE}, address = {New York}, isbn = {978-1-5386-9133-5}, issn = {2163-2871}, doi = {10.1109/SOCA.2018.00032}, pages = {169 -- 176}, year = {2019}, abstract = {In cloud computing, users are able to use their own operating system (OS) image to run a virtual machine (VM) on a remote host. The virtual machine OS is started by the user using some interfaces provided by a cloud provider in public or private cloud. In peer to peer cloud, the VM is started by the host admin. After the VM is running, the user could get a remote access to the VM to install, configure, and run services. For the security reasons, the user needs to verify the integrity of the running VM, because a malicious host admin could modify the image or even replace the image with a similar image, to be able to get sensitive data from the VM. We propose an approach to verify the integrity of a running VM on a remote host, without using any specific hardware such as Trusted Platform Module (TPM). Our approach is implemented on a Linux platform where the kernel files (vmlinuz and initrd) could be replaced with new files, while the VM is running. kexec is used to reboot the VM with the new kernel files. The new kernel has secret codes that will be used to verify whether the VM was started using the new kernel files. The new kernel is used to further measuring the integrity of the running VM.}, language = {en} } @article{Boettinger2019, author = {B{\"o}ttinger, Erwin}, title = {Wendepunkt f{\"u}r Gesundheit}, series = {Die Zukunft der Medizin : Disruptive Innovationen revolutionieren Medizin und Gesundheit}, journal = {Die Zukunft der Medizin : Disruptive Innovationen revolutionieren Medizin und Gesundheit}, publisher = {Medizinisch Wissenschaftliche Verlagsgesellschaft}, address = {Berlin}, isbn = {978-3-95466-398-9}, pages = {201 -- 210}, year = {2019}, language = {de} }