TY - JOUR A1 - Lamprecht, Anna-Lena A1 - Margaria, Tiziana ED - Lambrecht, Anna-Lena ED - Margaria, Tiziana T1 - Scientific Workflows and XMDD JF - Process Design for Natural Scientists: an agile model-driven approach N2 - A major part of the scientific experiments that are carried out today requires thorough computational support. While database and algorithm providers face the problem of bundling resources to create and sustain powerful computation nodes, the users have to deal with combining sets of (remote) services into specific data analysis and transformation processes. Today’s attention to “big data” amplifies the issues of size, heterogeneity, and process-level diversity/integration. In the last decade, especially workflow-based approaches to deal with these processes have enjoyed great popularity. This book concerns a particularly agile and model-driven approach to manage scientific workflows that is based on the XMDD paradigm. In this chapter we explain the scope and purpose of the book, briefly describe the concepts and technologies of the XMDD paradigm, explain the principal differences to related approaches, and outline the structure of the book. Y1 - 2014 SN - 978-3-662-45005-5 SN - 1865-0929 IS - 500 SP - 1 EP - 13 PB - Springer Verlag CY - Berlin ER - TY - JOUR A1 - Lamprecht, Anna-Lena A1 - Wickert, Alexander A1 - Margaria, Tiziana ED - Lambrecht, Anna-Lena ED - Margaria, Tiziana T1 - Lessons Learned JF - Process Design for Natural Scientists: an agile model-driven approach N2 - This chapter summarizes the experience and the lessons we learned concerning the application of the jABC as a framework for design and execution of scientific workflows. It reports experiences from the domain modeling (especially service integration) and workflow design phases and evaluates the resulting models statistically with respect to the SIB library and hierarchy levels. Y1 - 2014 SN - 978-3-662-45005-5 SN - 1865-0929 IS - 500 SP - 45 EP - 64 PB - Springer Verlag CY - Berlin ER - TY - JOUR A1 - Lamprecht, Anna-Lena A1 - Wickert, Alexander ED - Lambrecht, Anna-Lena ED - Margaria, Tiziana T1 - The Course's SIB Libraries JF - Process Design for Natural Scientists: an agile model-driven approach N2 - This chapter gives a detailed description of the service framework underlying all the example projects that form the foundation of this book. It describes the different SIB libraries that we made available for the course “Process modeling in the natural sciences” to provide the functionality that was required for the envisaged applications. The students used these SIB libraries to realize their projects. Y1 - 2014 SN - 978-3-662-45005-5 SN - 1865-0929 IS - 500 SP - 30 EP - 44 PB - Springer Verlag CY - Berlin ER - TY - JOUR A1 - Lamprecht, Anna-Lena A1 - Margaria, Tiziana ED - Lamprecht, Anna-Lena ED - Margaria, Tiziana T1 - Scientific workflows and XMDD JF - Process design for natural scientists Y1 - 2015 SN - 978-3-662-45006-2 SP - 1 EP - 13 PB - Springer CY - Berlin ER - TY - CHAP A1 - Rojahn, Marcel A1 - Gronau, Norbert T1 - Digital platform concepts for manufacturing companies BT - a review T2 - 10th International Conference on Future Internet of Things and Cloud (FiCloud) N2 - Digital Platforms (DPs) has established themself in recent years as a central concept of the Information Technology Science. Due to the great diversity of digital platform concepts, clear definitions are still required. Furthermore, DPs are subject to dynamic changes from internal and external factors, which pose challenges for digital platform operators, developers and customers. Which current digital platform research directions should be taken to address these challenges remains open so far. The following paper aims to contribute to this by outlining a systematic literature review (SLR) on digital platform concepts in the context of the Industrial Internet of Things (IIoT) for manufacturing companies and provides a basis for (1) a selection of definitions of current digital platform and ecosystem concepts and (2) a selection of current digital platform research directions. These directions are diverted into (a) occurrence of digital platforms, (b) emergence of digital platforms, (c) evaluation of digital platforms, (d) development of digital platforms, and (e) selection of digital platforms. Y1 - 2023 SN - 979-8-3503-1635-3 U6 - https://doi.org/10.1109/FiCloud58648.2023.00030 SP - 149 EP - 158 PB - IEEE CY - [Erscheinungsort nicht ermittelbar] ER - TY - JOUR A1 - de Wiljes, Jana A1 - Pathiraja, Sahani Darschika A1 - Reich, Sebastian T1 - Ensemble transform algorithms for nonlinear smoothing problems JF - SIAM journal on scientific computing N2 - Several numerical tools designed to overcome the challenges of smoothing in a non-linear and non-Gaussian setting are investigated for a class of particle smoothers. The considered family of smoothers is induced by the class of linear ensemble transform filters which contains classical filters such as the stochastic ensemble Kalman filter, the ensemble square root filter, and the recently introduced nonlinear ensemble transform filter. Further the ensemble transform particle smoother is introduced and particularly highlighted as it is consistent in the particle limit and does not require assumptions with respect to the family of the posterior distribution. The linear update pattern of the considered class of linear ensemble transform smoothers allows one to implement important supplementary techniques such as adaptive spread corrections, hybrid formulations, and localization in order to facilitate their application to complex estimation problems. These additional features are derived and numerically investigated for a sequence of increasingly challenging test problems. KW - data assimilation KW - smoother KW - localization KW - optimal transport KW - adaptive KW - spread correction Y1 - 2019 U6 - https://doi.org/10.1137/19M1239544 SN - 1064-8275 SN - 1095-7197 VL - 42 IS - 1 SP - A87 EP - A114 PB - Society for Industrial and Applied Mathematics CY - Philadelphia ER - TY - JOUR A1 - Marx, Julian A1 - Stieglitz, Stefan A1 - Brünker, Felix A1 - Mirbabaie, Milad T1 - Home (office) is where your heart is BT - exploring the identity of the ‘corporate nomad’ knowledge worker archetype JF - Business & information systems engineering N2 - Working conditions of knowledge workers have been subject to rapid change recently. Digital nomadism is no longer a phenomenon that relates only to entrepreneurs, freelancers, and gig workers. Corporate employees, too, have begun to uncouple their work from stationary (home) offices and 9-to-5 schedules. However, pursuing a permanent job in a corporate environment is still subject to fundamentally different values than postulated by the original notion of digital nomadism. Therefore, this paper explores the work identity of what is referred to as ‘corporate nomads’. By drawing on identity theory and the results of semi-structured interviews, the paper proposes a conceptualization of the corporate nomad archetype and presents nine salient identity issues of corporate nomads (e.g., holding multiple contradictory identities, the flexibility paradox, or collaboration constraints). By introducing the ‘corporate nomad’ archetype to the Information Systems literature, this article helps to rethink established conceptions of “home office” and socio-spatial configurations of knowledge work. KW - corporate nomadism KW - identity theory KW - home office KW - knowledge work KW - digital nomadism Y1 - 2023 U6 - https://doi.org/10.1007/s12599-023-00807-w SN - 2363-7005 SN - 1867-0202 VL - 65 IS - 3 SP - 293 EP - 308 PB - Springer Gabler CY - Wiesbaden ER - TY - JOUR A1 - Hofeditz, Lennart A1 - Mirbabaie, Milad A1 - Ortmann, Mara T1 - Ethical challenges for human–agent interaction in virtual collaboration at work JF - International journal of human computer interaction N2 - In virtual collaboration at the workplace, a growing number of teams apply supportive conversational agents (CAs). They take on different work-related tasks for teams and single users such as scheduling meetings or stimulating creativity. Previous research merely focused on these positive aspects of introducing CAs at the workplace, omitting ethical challenges faced by teams using these often artificial intelligence (AI)-enabled technologies. Thus, on the one hand, CAs can present themselves as benevolent teammates, but on the other hand, they can collect user data, reduce worker autonomy, or foster social isolation by their service. In this work, we conducted 15 expert interviews with senior researchers from the fields of ethics, collaboration, and computer science in order to derive ethical guidelines for introducing CAs in virtual team collaboration. We derived 14 guidelines and seven research questions to pave the way for future research on the dark sides of human–agent interaction in organizations. KW - conversational agents KW - human–computer interaction KW - virtual collaboration KW - ethics KW - virtual teams KW - trust Y1 - 2023 U6 - https://doi.org/10.1080/10447318.2023.2279400 SN - 1044-7318 SN - 1532-7590 PB - Taylor & Francis CY - New York, NY ER - TY - JOUR A1 - Brünker, Felix A1 - Marx, Julian A1 - Mirbabaie, Milad A1 - Stieglitz, Stefan T1 - Proactive digital workplace transformation BT - unpacking identity change mechanisms in remote-first organisations JF - Journal of information technology N2 - Digital transformation fundamentally changes the way individuals conduct work in organisations. In accordance with this statement, prevalent literature understands digital workplace transformation as a second-order effect of implementing new information technology to increase organisational effectiveness or reach other strategic goals. This paper, in contrast, provides empirical evidence from two remote-first organisations that undergo a proactive rather than reactive digital workplace transformation. The analysis of these cases suggests that new ways of working can be the consequence of an identity change that is a precondition for introducing new information technology rather than its outcome. The resulting process model contributes a competing argument to the existing debate in digital transformation literature. Instead of issuing digital workplace transformation as a deliverable of technological progress and strategic goals, this paper supports a notion of digital workplace transformation that serves a desired identity based on work preferences. KW - digital transformation KW - digital workplace transformation KW - remote-first KW - identity theory Y1 - 2023 U6 - https://doi.org/10.1177/02683962231219516 SN - 0268-3962 SN - 1466-4437 PB - Sage Publishing CY - London ER - TY - JOUR A1 - Rüdian, Sylvio Leo A1 - Vladova, Gergana T1 - Kostenfreie Onlinekurse nachhaltig mit personalisiertem Marketing finanzieren BT - ein Vorschlag zur synergetischen Kombination zweier datengetriebener Geschäftsmodelle JF - HMD Praxis der Wirtschaftsinformatik N2 - Selbstbestimmtes Lernen mit Onlinekursen findet zunehmend mehr Akzeptanz in unserer Gesellschaft. Lernende können mithilfe von Onlinekursen selbst festlegen, was sie wann lernen und Kurse können durch vielfältige Adaptionen an den Lernfortschritt der Nutzer angepasst und individualisiert werden. Auf der einen Seite ist eine große Zielgruppe für diese Lernangebote vorhanden. Auf der anderen Seite sind die Erstellung von Onlinekursen, ihre Bereitstellung, Wartung und Betreuung kostenintensiv, wodurch hochwertige Angebote häufig kostenpflichtig angeboten werden müssen, um als Anbieter zumindest kostenneutral agieren zu können. In diesem Beitrag erörtern und diskutieren wir ein offenes, nachhaltiges datengetriebenes zweiseitiges Geschäftsmodell zur Verwertung geprüfter Onlinekurse und deren kostenfreie Bereitstellung für jeden Lernenden. Kern des Geschäftsmodells ist die Nutzung der dabei entstehenden Verhaltensdaten, die daraus mögliche Ableitung von Persönlichkeitsmerkmalen und Interessen und deren Nutzung im kommerziellen Kontext. Dies ist eine bei der Websuche bereits weitläufig akzeptierte Methode, welche nun auf den Lernkontext übertragen wird. Welche Möglichkeiten, Herausforderungen, aber auch Barrieren überwunden werden müssen, damit das Geschäftsmodell nachhaltig und ethisch vertretbar funktioniert, werden zwei unabhängige, jedoch synergetisch verbundene Geschäftsmodelle vorgestellt und diskutiert. Zusätzlich wurde die Akzeptanz und Erwartung der Zielgruppe für das vorgestellte Geschäftsmodell untersucht, um notwendige Kernressourcen für die Praxis abzuleiten. Die Ergebnisse der Untersuchung zeigen, dass das Geschäftsmodell von den Nutzer*innen grundlegend akzeptiert wird. 10 % der Befragten würden es bevorzugen, mit virtuellen Assistenten – anstelle mit Tutor*innen zu lernen. Zudem ist der Großteil der Nutzer*innen sich nicht darüber bewusst, dass Persönlichkeitsmerkmale anhand des Nutzerverhaltens abgeleitet werden können. KW - Onlinekurse KW - Big Data KW - Geschäftsmodell KW - Werbung KW - Marketing KW - Canvas Y1 - 2021 U6 - https://doi.org/10.1365/s40702-021-00720-4 SN - 1436-3011 VL - 58 IS - 3 SP - 507 EP - 520 PB - Springer Vieweg CY - Wiesbaden ER - TY - JOUR A1 - Studen, Laura A1 - Tiberius, Victor T1 - Social Media, Quo Vadis? BT - Prospective Development and Implications JF - Future Internet N2 - Over the past two decades, social media have become a crucial and omnipresent cultural and economic phenomenon, which has seen platforms come and go and advance technologically. In this study, we explore the further development of social media regarding interactive technologies, platform development, relationships to news media, the activities of institutional and organizational users, and effects of social media on the individual and the society over the next five to ten years by conducting an international, two-stage Delphi study. Our results show that enhanced interaction on platforms, including virtual and augmented reality, somatosensory sense, and touch- and movement-based navigation are expected. AIs will interact with other social media users. Inactive user profiles will outnumber active ones. Platform providers will diversify into the WWW, e-commerce, edu-tech, fintechs, the automobile industry, and HR. They will change to a freemium business model and put more effort into combating cybercrime. Social media will become the predominant news distributor, but fake news will still be problematic. Firms will spend greater amounts of their budgets on social media advertising, and schools, politicians, and the medical sector will increase their social media engagement. Social media use will increasingly lead to individuals’ psychic issues. Society will benefit from economic growth and new jobs, increased political interest, democratic progress, and education due to social media. However, censorship and the energy consumption of platform operators might rise. KW - Delphi study KW - individual effects KW - interactive technologies KW - news media KW - social media KW - societal effects Y1 - 2020 U6 - https://doi.org/10.3390/fi12090146 SN - 1999-5903 VL - 12 IS - 9 PB - MDPI CY - Basel ER - TY - JOUR A1 - von Steinau-Steinrück, Robert A1 - Bruhn, Emma T1 - Der Impfmuffel im Arbeitsrecht JF - NJW spezial N2 - Trotz erfolgreicher Impfkampagne droht nach dem Sommer eine vierte Infektionswelle der Corona-Pandemie. Ob es dazu kommen wird, hängt maßgeblich davon ab, wie viele Menschen sich für eine Corona-Schutzimpfung entscheiden. Am Impfstoff mangelt es nicht mehr, dafür an der Impfbereitschaft. Viele Arbeitgeber fragen sich daher, was sie unternehmen können, um die Impfquote in ihren Betrieben zu erhöhen. Y1 - 2021 UR - https://beck-online.beck.de/Bcid/Y-300-Z-NJW-SPEZIAL-B-2021-S-498-N-1 SN - 1613-4621 VL - 18 IS - 16 SP - 498 EP - 499 PB - C.H. Beck CY - München ER - TY - JOUR A1 - Bläsius, Thomas A1 - Friedrich, Tobias A1 - Lischeid, Julius A1 - Meeks, Kitty A1 - Schirneck, Friedrich Martin T1 - Efficiently enumerating hitting sets of hypergraphs arising in data profiling JF - Journal of computer and system sciences : JCSS N2 - The transversal hypergraph problem asks to enumerate the minimal hitting sets of a hypergraph. If the solutions have bounded size, Eiter and Gottlob [SICOMP'95] gave an algorithm running in output-polynomial time, but whose space requirement also scales with the output. We improve this to polynomial delay and space. Central to our approach is the extension problem, deciding for a set X of vertices whether it is contained in any minimal hitting set. We show that this is one of the first natural problems to be W[3]-complete. We give an algorithm for the extension problem running in time O(m(vertical bar X vertical bar+1) n) and prove a SETH-lower bound showing that this is close to optimal. We apply our enumeration method to the discovery problem of minimal unique column combinations from data profiling. Our empirical evaluation suggests that the algorithm outperforms its worst-case guarantees on hypergraphs stemming from real-world databases. KW - Data profiling KW - Enumeration algorithm KW - Minimal hitting set KW - Transversal hypergraph KW - Unique column combination KW - W[3]-Completeness Y1 - 2022 U6 - https://doi.org/10.1016/j.jcss.2021.10.002 SN - 0022-0000 SN - 1090-2724 VL - 124 SP - 192 EP - 213 PB - Elsevier CY - San Diego ER - TY - JOUR A1 - von Steinau-Steinrück, Robert A1 - Kurth, Paula Sophie T1 - Das reformierte Statusfeststellungsverfahren in der Praxis JF - NJW spezial N2 - Das Statusfeststellungsverfahren ermöglicht auf Antrag bei der alleinzuständigen Deutschen Rentenversicherung Bund den Erhalt einer verbindlichen Einschätzung der häufig komplizierten und folgenschweren Abgrenzung einer selbstständigen Tätigkeit von einer abhängigen Beschäftigung. Zum 1.4.2022 wurde das Statusfeststellungsverfahren umfassend reformiert. In der Praxis haben sich die eingeführten Novellierungen bislang unterschiedlich bewährt. Y1 - 2022 UR - https://beck-online.beck.de/Bcid/Y-300-Z-NJW-SPEZIAL-B-2022-S-754-N-1 SN - 1613-4621 VL - 19 IS - 24 SP - 754 EP - 755 PB - C.H. Beck CY - München ER - TY - JOUR A1 - von Steinau-Steinrück, Robert A1 - Sura, Stephan T1 - Die (Rest-)Zulässigkeit von Verboten religiöser Zeichen am Arbeitsplatz JF - NJW spezial N2 - In einer Reihe von Urteilen hat der EuGH seit 2017 die Zulässigkeit von Verboten religiöser Zeichen und Kleidung am Arbeitsplatz bewertet. Obwohl die Einordnungen des Gerichtshofs der deutschen Rechtslage zunächst diametral entgegenstanden, hat sich diese letztlich nicht verändert. Y1 - 2023 UR - https://beck-online.beck.de/Bcid/Y-300-Z-NJW-SPEZIAL-B-2023-S-242-N-1 SN - 1613-4621 VL - 20 IS - 8 SP - 242 EP - 243 PB - C.H. Beck CY - München ER - TY - JOUR A1 - von Steinau-Steinrück, Robert A1 - Miller, Denis T1 - Rückzahlungsklauseln für Fortbildungen BT - typische Fehler JF - Neue juristische Wochenschrift : NJW Spezial N2 - Mit Urteil vom 1.3.2022 (NZA2022, NZA Jahr 2022 Seite 780) hat das BAG erneut über die Wirksamkeit einer Rückzahlungsklausel in einer Fortbildungsvereinbarung entschieden. Die Entscheidung reiht sich in eine nicht leicht zu durchschauende Anzahl von Urteilen hierzu ein. Sie dient uns zum Anlass, einen Überblick über die Rechtsprechung zu geben. Y1 - 2022 UR - https://beck-online.beck.de/Bcid/Y-300-Z-NJW-SPEZIAL-B-2022-S-370-N-1 SN - 1613-4621 VL - 19 IS - 12 SP - 370 EP - 371 PB - C.H. Beck CY - München ER - TY - JOUR A1 - von Steinau-Steinrück, Robert A1 - Jöris, Nils T1 - Brexit-Arbeitsrecht und die Folgen JF - NJW spezial N2 - Die Corona-Pandemie hat den Brexit ein wenig in den Hintergrund gedrängt. Dabei hat er gerade im Arbeitsrecht ganz erhebliche Auswirkungen. Über sie geben wir einen Überblick. Y1 - 2021 UR - https://beck-online.beck.de/Bcid/Y-300-Z-NJW-SPEZIAL-B-2021-S-242-N-1 SN - 1613-4621 VL - 18 IS - 8 SP - 242 EP - 243 PB - C.H. Beck CY - München ER - TY - JOUR A1 - von Steinau-Steinrück, Robert A1 - Höltge, Clara T1 - Krieg in Europa BT - Beschäftigung ukrainischer Geflüchteter in Deutschland JF - NJW spezial N2 - Am 24.2.2022 begann der russische Angriffskrieg in der Ukraine. Seitdem fliehen täglich zahlreiche ukrainische Staatsbürger in die Europäische Union, viele davon nach Deutschland. Vorrangig ist jetzt die Sicherung der Grundbedürfnisse, wie Verpflegung, Unterkunft und medizinischer Versorgung. Daneben fragen sich Arbeitgeber, wie sie ukrainische Staatsbürger möglichst schnell beschäftigen können. Wir geben einen Überblick über die Möglichkeiten, ukrainische Geflüchtete möglichst schnell in den deutschen Arbeitsmarkt zu integrieren. Y1 - 2022 UR - https://beck-online.beck.de/Bcid/Y-300-Z-NJW-SPEZIAL-B-2022-S-242-N-1 SN - 1613-4621 VL - 19 IS - 8 SP - 242 EP - 243 PB - C.H. Beck CY - München ER - TY - JOUR A1 - von Steinau-Steinrück, Robert A1 - Beismann, Lukas T1 - (Corona-)Homeoffice und betriebliche Übung JF - NJW spezial N2 - Homeoffice und mobiles Arbeiten haben sich infolge der Covid-19-Pandemie bei vielen Unternehmen bekanntlich etabliert. Die Anweisung bzw. „Duldung“ des Homeoffice beruhte allerdings meist mehr auf tatsächlicher als auf rechtlicher Grundlage. Letztere könnte aber aus betrieblicher Übung erwachsen. Dieser Beitrag geht dem rechtlichen Rahmen dafür nach. Y1 - 2020 UR - https://beck-online.beck.de/Bcid/Y-300-Z-NJW-SPEZIAL-B-2020-S-626-N-1 SN - 1613-4621 VL - 17 IS - 20 SP - 626 EP - 627 PB - C.H. Beck CY - München ER - TY - JOUR A1 - von Steinau-Steinrück, Robert T1 - Was ist bei "Workation" und "Bleisure" rechtlich zu beachten? JF - NJW spezial N2 - Die Digitalisierung unseres Lebens löst die Grenzen zwischen Privat- und Berufsleben immer weiter auf. Bekanntes Beispiel ist das Homeoffice. Arbeitgeber begegnen aber auch zahlreichen weiteren Trends in diesem Zusammenhang. Dazu gehören „workation“, also die Verbindung zwischen Arbeit („work“) und Urlaub („vacation“) ebenso wie „bleisure“, dh die Verbindung von Dienstreisen („business“) und Urlaub („leisure“). Der Beitrag geht den rechtlichen Rahmenbedingungen hierfür nach. Y1 - 2021 UR - https://beck-online.beck.de/Bcid/Y-300-Z-NJW-SPEZIAL-B-2021-S-626-N-1 SN - 1613-4621 VL - 18 IS - 20 SP - 626 EP - 627 PB - C.H. Beck CY - München ER - TY - JOUR A1 - von Steinau-Steinrück, Robert A1 - Jöris, Nils T1 - Arbeitsschutz bei Corona BT - Versuch einer Entwirrung JF - NJW spezial N2 - Den Überblick im Arbeitsschutzrecht zu behalten, ist schwierig. Der Arbeitsschutz spielt sich in unterschiedlichen Bereichen und auf verschiedenen Ebenen ab. Außerdem sind die einschlägigen Rechtsnormen überaus verästelt. Der folgende Beitrag soll daher zur Entwirrung beitragen. Y1 - 2020 UR - https://beck-online.beck.de/Bcid/Y-300-Z-NJW-SPEZIAL-B-2020-S-370-N-1 SN - 1613-4621 VL - 17 IS - 12 SP - 370 EP - 371 PB - C.H. Beck CY - München ER - TY - GEN A1 - von Steinau-Steinrück, Robert T1 - Gesetzesentwurf zu Corona-bedingten Änderungen des ArbGG/SGG T2 - NJW spezial Y1 - 2020 UR - https://beck-online.beck.de/Bcid/Y-300-Z-NJW-SPEZIAL-B-2020-S-340-N-2 SN - 1613-4621 VL - 17 IS - 11 SP - 340 EP - 340 PB - C.H. Beck CY - München ER - TY - GEN A1 - von Steinau-Steinrück, Robert T1 - Koalitionsausschuss beschließt Verlängerung des Kurzarbeitergelds T2 - NJW spezial Y1 - 2020 UR - https://beck-online.beck.de/Bcid/Y-300-Z-NJW-SPEZIAL-B-2020-S-596-N-2 SN - 1613-4621 VL - 17 IS - 19 SP - 596 EP - 596 PB - C.H. Beck CY - München ER - TY - GEN A1 - Hesse, Günter A1 - Matthies, Christoph A1 - Sinzig, Werner A1 - Uflacker, Matthias T1 - Adding Value by Combining Business and Sensor Data BT - an Industry 4.0 Use Case T2 - Database Systems for Advanced Applications N2 - 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. KW - Industry 4.0 KW - Internet of Things KW - Data integration Y1 - 2019 SN - 978-3-030-18590-9 SN - 978-3-030-18589-3 U6 - https://doi.org/10.1007/978-3-030-18590-9_80 SN - 0302-9743 SN - 1611-3349 VL - 11448 SP - 528 EP - 532 PB - Springer CY - Cham ER - TY - JOUR A1 - Wang, Cheng A1 - Yang, Haojin A1 - Meinel, Christoph T1 - Image Captioning with Deep Bidirectional LSTMs and Multi-Task Learning JF - ACM transactions on multimedia computing, communications, and applications N2 - Generating a novel and descriptive caption of an image is drawing increasing interests in computer vision, natural language processing, and multimedia communities. In this work, we propose an end-to-end trainable deep bidirectional LSTM (Bi-LSTM (Long Short-Term Memory)) model to address the problem. By combining a deep convolutional neural network (CNN) and two separate LSTM networks, our model is capable of learning long-term visual-language interactions by making use of history and future context information at high-level semantic space. We also explore deep multimodal bidirectional models, in which we increase the depth of nonlinearity transition in different ways to learn hierarchical visual-language embeddings. Data augmentation techniques such as multi-crop, multi-scale, and vertical mirror are proposed to prevent over-fitting in training deep models. To understand how our models "translate" image to sentence, we visualize and qualitatively analyze the evolution of Bi-LSTM internal states over time. The effectiveness and generality of proposed models are evaluated on four benchmark datasets: Flickr8K, Flickr30K, MSCOCO, and Pascal1K datasets. We demonstrate that Bi-LSTM models achieve highly competitive performance on both caption generation and image-sentence retrieval even without integrating an additional mechanism (e.g., object detection, attention model). Our experiments also prove that multi-task learning is beneficial to increase model generality and gain performance. We also demonstrate the performance of transfer learning of the Bi-LSTM model significantly outperforms previous methods on the Pascal1K dataset. KW - Deep learning KW - LSTM KW - multimodal representations KW - image captioning KW - mutli-task learning Y1 - 2018 U6 - https://doi.org/10.1145/3115432 SN - 1551-6857 SN - 1551-6865 VL - 14 IS - 2 PB - Association for Computing Machinery CY - New York ER - TY - CHAP A1 - Grüner, Andreas A1 - Mühle, Alexander A1 - Gayvoronskaya, Tatiana A1 - Meinel, Christoph T1 - A quantifiable trustmModel for Blockchain-based identity management T2 - 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 KW - Blockchain KW - distributed ledger technology KW - digital identity KW - self-sovereign identity KW - trust KW - identity management Y1 - 2019 SN - 978-1-5386-7975-3 U6 - https://doi.org/10.1109/Cybermatics_2018.2018.00250 SP - 1475 EP - 1482 PB - IEEE CY - New York ER - TY - JOUR A1 - Chujfi-La-Roche, Salim A1 - Meinel, Christoph T1 - Matching cognitively sympathetic individual styles to develop collective intelligence in digital communities JF - AI & society : the journal of human-centred systems and machine intelligence N2 - Creation, collection and retention of knowledge in digital communities is an activity that currently requires being explicitly targeted as a secure method of keeping intellectual capital growing in the digital era. In particular, we consider it relevant to analyze and evaluate the empathetic cognitive personalities and behaviors that individuals now have with the change from face-to-face communication (F2F) to computer-mediated communication (CMC) online. This document proposes a cyber-humanistic approach to enhance the traditional SECI knowledge management model. A cognitive perception is added to its cyclical process following design thinking interaction, exemplary for improvement of the method in which knowledge is continuously created, converted and shared. In building a cognitive-centered model, we specifically focus on the effective identification and response to cognitive stimulation of individuals, as they are the intellectual generators and multiplicators of knowledge in the online environment. Our target is to identify how geographically distributed-digital-organizations should align the individual's cognitive abilities to promote iteration and improve interaction as a reliable stimulant of collective intelligence. The new model focuses on analyzing the four different stages of knowledge processing, where individuals with sympathetic cognitive personalities can significantly boost knowledge creation in a virtual social system. For organizations, this means that multidisciplinary individuals can maximize their extensive potential, by externalizing their knowledge in the correct stage of the knowledge creation process, and by collaborating with their appropriate sympathetically cognitive remote peers. KW - argumentation research KW - cyber humanistic KW - cognition KW - collaboration KW - knowledge building KW - knowledge management KW - teamwork KW - virtual groups Y1 - 2017 U6 - https://doi.org/10.1007/s00146-017-0780-x SN - 0951-5666 SN - 1435-5655 VL - 35 IS - 1 SP - 5 EP - 15 PB - Springer CY - New York ER - TY - JOUR A1 - Torkura, Kennedy A. A1 - Sukmana, Muhammad Ihsan Haikal A1 - Cheng, Feng A1 - Meinel, Christoph T1 - CloudStrike BT - chaos engineering for security and resiliency in cloud infrastructure JF - IEEE access : practical research, open solutions N2 - Most cyber-attacks and data breaches in cloud infrastructure are due to human errors and misconfiguration vulnerabilities. Cloud customer-centric tools are imperative for mitigating these issues, however existing cloud security models are largely unable to tackle these security challenges. Therefore, novel security mechanisms are imperative, we propose Risk-driven Fault Injection (RDFI) techniques to address these challenges. RDFI applies the principles of chaos engineering to cloud security and leverages feedback loops to execute, monitor, analyze and plan security fault injection campaigns, based on a knowledge-base. The knowledge-base consists of fault models designed from secure baselines, cloud security best practices and observations derived during iterative fault injection campaigns. These observations are helpful for identifying vulnerabilities while verifying the correctness of security attributes (integrity, confidentiality and availability). Furthermore, RDFI proactively supports risk analysis and security hardening efforts by sharing security information with security mechanisms. We have designed and implemented the RDFI strategies including various chaos engineering algorithms as a software tool: CloudStrike. Several evaluations have been conducted with CloudStrike against infrastructure deployed on two major public cloud infrastructure: Amazon Web Services and Google Cloud Platform. The time performance linearly increases, proportional to increasing attack rates. Also, the analysis of vulnerabilities detected via security fault injection has been used to harden the security of cloud resources to demonstrate the effectiveness of the security information provided by CloudStrike. Therefore, we opine that our approaches are suitable for overcoming contemporary cloud security issues. KW - cloud security KW - security chaos engineering KW - resilient architectures KW - security risk assessment Y1 - 2020 U6 - https://doi.org/10.1109/ACCESS.2020.3007338 SN - 2169-3536 VL - 8 SP - 123044 EP - 123060 PB - Institute of Electrical and Electronics Engineers  CY - Piscataway ER - TY - JOUR A1 - Grüner, Andreas A1 - Mühle, Alexander A1 - Meinel, Christoph T1 - ATIB BT - Design and evaluation of an architecture for brokered self-sovereign identity integration and trust-enhancing attribute aggregation for service provider JF - IEEE access : practical research, open solutions / Institute of Electrical and Electronics Engineers N2 - Identity management is a principle component of securing online services. In the advancement of traditional identity management patterns, the identity provider remained a Trusted Third Party (TTP). The service provider and the user need to trust a particular identity provider for correct attributes amongst other demands. This paradigm changed with the invention of blockchain-based Self-Sovereign Identity (SSI) solutions that primarily focus on the users. SSI reduces the functional scope of the identity provider to an attribute provider while enabling attribute aggregation. Besides that, the development of new protocols, disregarding established protocols and a significantly fragmented landscape of SSI solutions pose considerable challenges for an adoption by service providers. We propose an Attribute Trust-enhancing Identity Broker (ATIB) to leverage the potential of SSI for trust-enhancing attribute aggregation. Furthermore, ATIB abstracts from a dedicated SSI solution and offers standard protocols. Therefore, it facilitates the adoption by service providers. Despite the brokered integration approach, we show that ATIB provides a high security posture. Additionally, ATIB does not compromise the ten foundational SSI principles for the users. KW - Blockchains KW - Protocols KW - Authentication KW - Licenses KW - Security KW - Privacy KW - Identity management systems KW - Attribute aggregation KW - attribute assurance KW - digital identity KW - identity broker KW - self-sovereign identity KW - trust model Y1 - 2021 U6 - https://doi.org/10.1109/ACCESS.2021.3116095 SN - 2169-3536 VL - 9 SP - 138553 EP - 138570 PB - Institute of Electrical and Electronics Engineers CY - New York, NY ER - TY - CHAP A1 - Corazza, Giovanni Emanuele A1 - Thienen, Julia von ED - Glăveanu, Vlad Petre T1 - Invention T2 - The Palgrave encyclopedia of the possible N2 - This entry addresses invention from five different perspectives: (i) definition of the term, (ii) mechanisms underlying invention processes, (iii) (pre-)history of human inventions, (iv) intellectual property protection vs open innovation, and (v) case studies of great inventors. Regarding the definition, an invention is the outcome of a creative process taking place within a technological milieu, which is recognized as successful in terms of its effectiveness as an original technology. In the process of invention, a technological possibility becomes realized. Inventions are distinct from either discovery or innovation. In human creative processes, seven mechanisms of invention can be observed, yielding characteristic outcomes: (1) basic inventions, (2) invention branches, (3) invention combinations, (4) invention toolkits, (5) invention exaptations, (6) invention values, and (7) game-changing inventions. The development of humanity has been strongly shaped by inventions ever since early stone tools and the conception of agriculture. An “explosion of creativity” has been associated with Homo sapiens, and inventions in all fields of human endeavor have followed suit, engendering an exponential growth of cumulative culture. This culture development emerges essentially through a reuse of previous inventions, their revision, amendment and rededication. In sociocultural terms, humans have increasingly regulated processes of invention and invention-reuse through concepts such as intellectual property, patents, open innovation and licensing methods. Finally, three case studies of great inventors are considered: Edison, Marconi, and Montessori, next to a discussion of human invention processes as collaborative endeavors. KW - invention KW - creativity KW - invention mechanism KW - cumulative culture KW - technology KW - innovation KW - patent KW - open innovation Y1 - 2023 SN - 978-3-030-90912-3 SN - 978-3-030-90913-0 U6 - https://doi.org/10.1007/978-3-030-90913-0_14 SP - 806 EP - 814 PB - Springer International Publishing CY - Cham ER - TY - THES A1 - Schnjakin, Maxim T1 - Cloud-RAID BT - eine Methode zur Bereitstellung zuverlässiger Speicherressourcen in öffentlichen Clouds Y1 - 2014 ER - TY - THES A1 - Wang, Cheng T1 - Deep Learning of Multimodal Representations Y1 - 2016 ER - TY - THES A1 - Saleh, Eyad T1 - Securing Multi-tenant SaaS Environments N2 - Software-as-a-Service (SaaS) offers several advantages to both service providers and users. Service providers can benefit from the reduction of Total Cost of Ownership (TCO), better scalability, and better resource utilization. On the other hand, users can use the service anywhere and anytime, and minimize upfront investment by following the pay-as-you-go model. Despite the benefits of SaaS, users still have concerns about the security and privacy of their data. Due to the nature of SaaS and the Cloud in general, the data and the computation are beyond the users' control, and hence data security becomes a vital factor in this new paradigm. Furthermore, in multi-tenant SaaS applications, the tenants become more concerned about the confidentiality of their data since several tenants are co-located onto a shared infrastructure. To address those concerns, we start protecting the data from the provisioning process by controlling how tenants are being placed in the infrastructure. We present a resource allocation algorithm designed to minimize the risk of co-resident tenants called SecPlace. It enables the SaaS provider to control the resource (i.e., database instance) allocation process while taking into account the security of tenants as a requirement. Due to the design principles of the multi-tenancy model, tenants follow some degree of sharing on both application and infrastructure levels. Thus, strong security-isolation should be present. Therefore, we develop SignedQuery, a technique that prevents one tenant from accessing others' data. We use the Signing Concept to create a signature that is used to sign the tenant's request, then the server can verifies the signature and recognizes the requesting tenant, and hence ensures that the data to be accessed is belonging to the legitimate tenant. Finally, Data confidentiality remains a critical concern due to the fact that data in the Cloud is out of users' premises, and hence beyond their control. Cryptography is increasingly proposed as a potential approach to address such a challenge. Therefore, we present SecureDB, a system designed to run SQL-based applications over an encrypted database. SecureDB captures the schema design and analyzes it to understand the internal structure of the data (i.e., relationships between the tables and their attributes). Moreover, we determine the appropriate partialhomomorphic encryption scheme for each attribute where computation is possible even when the data is encrypted. To evaluate our work, we conduct extensive experiments with di↵erent settings. The main use case in our work is a popular open source HRM application, called OrangeHRM. The results show that our multi-layered approach is practical, provides enhanced security and isolation among tenants, and have a moderate complexity in terms of processing encrypted data. Y1 - 2016 ER - TY - THES A1 - Sadr-Azodi, Amir Shahab T1 - Towards Real-time SIEM-based Network monitoring and Intrusion Detection through Advanced Event Normalization Y1 - 2015 ER - TY - THES A1 - Malchow, Martin T1 - Nutzerunterstützung und -Motivation in E-Learning Vorlesungsarchiven und MOOCs N2 - In den letzten Jahren ist die Aufnahme und Verbreitung von Videos immer einfacher geworden. Daher sind die Relevanz und Beliebtheit zur Aufnahme von Vorlesungsvideos in den letzten Jahren stark angestiegen. Dies führt zu einem großen Datenbestand an Vorlesungsvideos in den Video-Vorlesungsarchiven der Universitäten. Durch diesen wachsenden Datenbestand wird es allerdings für die Studenten immer schwieriger, die relevanten Videos eines Vorlesungsarchivs aufzufinden. Zusätzlich haben viele Lerninteressierte durch ihre alltägliche Arbeit und familiären Verpflichtungen immer weniger Zeit sich mit dem Lernen zu beschäftigen. Ein weiterer Aspekt, der das Lernen im Internet erschwert, ist, dass es durch soziale Netzwerke und anderen Online-Plattformen vielfältige Ablenkungsmöglichkeiten gibt. Daher ist das Ziel dieser Arbeit, Möglichkeiten aufzuzeigen, welche das E-Learning bieten kann, um Nutzer beim Lernprozess zu unterstützen und zu motivieren. Das Hauptkonzept zur Unterstützung der Studenten ist das präzise Auffinden von Informationen in den immer weiter wachsenden Vorlesungsvideoarchiven. Dazu werden die Vorlesungen im Voraus analysiert und die Texte der Vorlesungsfolien mit verschiedenen Methoden indexiert. Daraufhin können die Studenten mit der Suche oder dem Lecture-Butler Lerninhalte entsprechend Ihres aktuellen Wissensstandes auffinden. Die möglichen verwendeten Technologien für das Auffinden wurden, sowohl technisch, als auch durch Studentenumfragen erfolgreich evaluiert. Zur Motivation von Studenten in Vorlesungsarchiven werden diverse Konzepte betrachtet und die Umsetzung evaluiert, die den Studenten interaktiv in den Lernprozess einbeziehen. Neben Vorlesungsarchiven existieren sowohl im privaten als auch im dienstlichen Weiterbildungsbereich die in den letzten Jahren immer beliebter werdenden MOOCs. Generell sind die Abschlussquoten von MOOCs allerdings mit durchschnittlich 7% eher gering. Daher werden Motivationslösungen für MOOCs im Bereich von eingebetteten Systemen betrachtet, die in praktischen Programmierkursen Anwendung finden. Zusätzlich wurden Kurse evaluiert, welche die Programmierung von eingebetteten Systemen behandeln. Die Verfügbarkeit war bei Kursen von bis zu 10.000 eingeschriebenen Teilnehmern hierbei kein schwerwiegendes Problem. Die Verwendung von eingebetteten Systemen in Programmierkursen sind bei den Studenten in der praktischen Umsetzung auf sehr großes Interesse gestoßen. Y1 - 2019 ER - TY - JOUR A1 - Bin Tareaf, Raad A1 - Berger, Philipp A1 - Hennig, Patrick A1 - Meinel, Christoph T1 - Cross-platform personality exploration system for online social networks BT - Facebook vs. Twitter JF - Web intelligence N2 - Social networking sites (SNS) are a rich source of latent information about individual characteristics. Crawling and analyzing this content provides a new approach for enterprises to personalize services and put forward product recommendations. In the past few years, commercial brands made a gradual appearance on social media platforms for advertisement, customers support and public relation purposes and by now it became a necessity throughout all branches. This online identity can be represented as a brand personality that reflects how a brand is perceived by its customers. We exploited recent research in text analysis and personality detection to build an automatic brand personality prediction model on top of the (Five-Factor Model) and (Linguistic Inquiry and Word Count) features extracted from publicly available benchmarks. Predictive evaluation on brands' accounts reveals that Facebook platform provides a slight advantage over Twitter platform in offering more self-disclosure for users' to express their emotions especially their demographic and psychological traits. Results also confirm the wider perspective that the same social media account carry a quite similar and comparable personality scores over different social media platforms. For evaluating our prediction results on actual brands' accounts, we crawled the Facebook API and Twitter API respectively for 100k posts from the most valuable brands' pages in the USA and we visualize exemplars of comparison results and present suggestions for future directions. KW - Big Five model KW - personality prediction KW - brand personality KW - machine KW - learning KW - social media analysis Y1 - 2020 U6 - https://doi.org/10.3233/WEB-200427 SN - 2405-6456 SN - 2405-6464 VL - 18 IS - 1 SP - 35 EP - 51 PB - IOS Press CY - Amsterdam ER - TY - JOUR A1 - Perscheid, Cindy T1 - Integrative biomarker detection on high-dimensional gene expression data sets BT - a survey on prior knowledge approaches JF - Briefings in bioinformatics N2 - Gene expression data provide the expression levels of tens of thousands of genes from several hundred samples. These data are analyzed to detect biomarkers that can be of prognostic or diagnostic use. Traditionally, biomarker detection for gene expression data is the task of gene selection. The vast number of genes is reduced to a few relevant ones that achieve the best performance for the respective use case. Traditional approaches select genes based on their statistical significance in the data set. This results in issues of robustness, redundancy and true biological relevance of the selected genes. Integrative analyses typically address these shortcomings by integrating multiple data artifacts from the same objects, e.g. gene expression and methylation data. When only gene expression data are available, integrative analyses instead use curated information on biological processes from public knowledge bases. With knowledge bases providing an ever-increasing amount of curated biological knowledge, such prior knowledge approaches become more powerful. This paper provides a thorough overview on the status quo of biomarker detection on gene expression data with prior biological knowledge. We discuss current shortcomings of traditional approaches, review recent external knowledge bases, provide a classification and qualitative comparison of existing prior knowledge approaches and discuss open challenges for this kind of gene selection. KW - gene selection KW - external knowledge bases KW - biomarker detection KW - gene KW - expression KW - prior knowledge Y1 - 2021 U6 - https://doi.org/10.1093/bib/bbaa151 SN - 1467-5463 SN - 1477-4054 VL - 22 IS - 3 PB - Oxford Univ. Press CY - Oxford ER - TY - JOUR A1 - Perscheid, Cindy T1 - Comprior BT - Facilitating the implementation and automated benchmarking of prior knowledge-based feature selection approaches on gene expression data sets JF - BMC Bioinformatics N2 - Background Reproducible benchmarking is important for assessing the effectiveness of novel feature selection approaches applied on gene expression data, especially for prior knowledge approaches that incorporate biological information from online knowledge bases. However, no full-fledged benchmarking system exists that is extensible, provides built-in feature selection approaches, and a comprehensive result assessment encompassing classification performance, robustness, and biological relevance. Moreover, the particular needs of prior knowledge feature selection approaches, i.e. uniform access to knowledge bases, are not addressed. As a consequence, prior knowledge approaches are not evaluated amongst each other, leaving open questions regarding their effectiveness. Results We present the Comprior benchmark tool, which facilitates the rapid development and effortless benchmarking of feature selection approaches, with a special focus on prior knowledge approaches. Comprior is extensible by custom approaches, offers built-in standard feature selection approaches, enables uniform access to multiple knowledge bases, and provides a customizable evaluation infrastructure to compare multiple feature selection approaches regarding their classification performance, robustness, runtime, and biological relevance. Conclusion Comprior allows reproducible benchmarking especially of prior knowledge approaches, which facilitates their applicability and for the first time enables a comprehensive assessment of their effectiveness KW - Feature selection KW - Prior knowledge KW - Gene expression KW - Reproducible benchmarking Y1 - 2021 U6 - https://doi.org/10.1186/s12859-021-04308-z SN - 1471-2105 VL - 22 SP - 1 EP - 15 PB - Springer Nature CY - London ER - TY - JOUR A1 - Loster, Michael A1 - Koumarelas, Ioannis A1 - Naumann, Felix T1 - Knowledge transfer for entity resolution with siamese neural networks JF - ACM journal of data and information quality N2 - The integration of multiple data sources is a common problem in a large variety of applications. Traditionally, handcrafted similarity measures are used to discover, merge, and integrate multiple representations of the same entity-duplicates-into a large homogeneous collection of data. Often, these similarity measures do not cope well with the heterogeneity of the underlying dataset. In addition, domain experts are needed to manually design and configure such measures, which is both time-consuming and requires extensive domain expertise.
We propose a deep Siamese neural network, capable of learning a similarity measure that is tailored to the characteristics of a particular dataset. With the properties of deep learning methods, we are able to eliminate the manual feature engineering process and thus considerably reduce the effort required for model construction. In addition, we show that it is possible to transfer knowledge acquired during the deduplication of one dataset to another, and thus significantly reduce the amount of data required to train a similarity measure. We evaluated our method on multiple datasets and compare our approach to state-of-the-art deduplication methods. Our approach outperforms competitors by up to +26 percent F-measure, depending on task and dataset. In addition, we show that knowledge transfer is not only feasible, but in our experiments led to an improvement in F-measure of up to +4.7 percent. KW - Entity resolution KW - duplicate detection KW - transfer learning KW - neural KW - networks KW - metric learning KW - similarity learning KW - data quality Y1 - 2021 U6 - https://doi.org/10.1145/3410157 SN - 1936-1955 SN - 1936-1963 VL - 13 IS - 1 PB - Association for Computing Machinery CY - New York ER - TY - JOUR A1 - Kaitoua, Abdulrahman A1 - Rabl, Tilmann A1 - Markl, Volker T1 - A distributed data exchange engine for polystores JF - Information technology : methods and applications of informatics and information technology JF - Information technology : Methoden und innovative Anwendungen der Informatik und Informationstechnik N2 - There is an increasing interest in fusing data from heterogeneous sources. Combining data sources increases the utility of existing datasets, generating new information and creating services of higher quality. A central issue in working with heterogeneous sources is data migration: In order to share and process data in different engines, resource intensive and complex movements and transformations between computing engines, services, and stores are necessary. Muses is a distributed, high-performance data migration engine that is able to interconnect distributed data stores by forwarding, transforming, repartitioning, or broadcasting data among distributed engines' instances in a resource-, cost-, and performance-adaptive manner. As such, it performs seamless information sharing across all participating resources in a standard, modular manner. We show an overall improvement of 30 % for pipelining jobs across multiple engines, even when we count the overhead of Muses in the execution time. This performance gain implies that Muses can be used to optimise large pipelines that leverage multiple engines. KW - distributed systems KW - data migration KW - data transformation KW - big data KW - engine KW - data integration Y1 - 2020 U6 - https://doi.org/10.1515/itit-2019-0037 SN - 1611-2776 SN - 2196-7032 VL - 62 IS - 3-4 SP - 145 EP - 156 PB - De Gruyter CY - Berlin ER - TY - JOUR A1 - Dreseler, Markus A1 - Boissier, Martin A1 - Rabl, Tilmann A1 - Uflacker, Matthias T1 - Quantifying TPC-H choke points and their optimizations JF - Proceedings of the VLDB Endowment N2 - TPC-H continues to be the most widely used benchmark for relational OLAP systems. It poses a number of challenges, also known as "choke points", which database systems have to solve in order to achieve good benchmark results. Examples include joins across multiple tables, correlated subqueries, and correlations within the TPC-H data set. Knowing the impact of such optimizations helps in developing optimizers as well as in interpreting TPC-H results across database systems. This paper provides a systematic analysis of choke points and their optimizations. It complements previous work on TPC-H choke points by providing a quantitative discussion of their relevance. It focuses on eleven choke points where the optimizations are beneficial independently of the database system. Of these, the flattening of subqueries and the placement of predicates have the biggest impact. Three queries (Q2, Q17, and Q21) are strongly ifluenced by the choice of an efficient query plan; three others (Q1, Q13, and Q18) are less influenced by plan optimizations and more dependent on an efficient execution engine. Y1 - 2020 U6 - https://doi.org/10.14778/3389133.3389138 SN - 2150-8097 VL - 13 IS - 8 SP - 1206 EP - 1220 PB - Association for Computing Machinery CY - New York ER - TY - JOUR A1 - Navarro, Marisa A1 - Orejas, Fernando A1 - Pino, Elvira A1 - Lambers, Leen T1 - A navigational logic for reasoning about graph properties JF - Journal of logical and algebraic methods in programming N2 - Graphs play an important role in many areas of Computer Science. In particular, our work is motivated by model-driven software development and by graph databases. For this reason, it is very important to have the means to express and to reason about the properties that a given graph may satisfy. With this aim, in this paper we present a visual logic that allows us to describe graph properties, including navigational properties, i.e., properties about the paths in a graph. The logic is equipped with a deductive tableau method that we have proved to be sound and complete. KW - Graph logic KW - Algebraic methods KW - Formal modelling KW - Specification Y1 - 2021 U6 - https://doi.org/10.1016/j.jlamp.2020.100616 SN - 2352-2208 SN - 2352-2216 VL - 118 PB - Elsevier Science CY - Amsterdam [u.a.] ER - TY - THES A1 - Makowski, Silvia T1 - Discriminative Models for Biometric Identification using Micro- and Macro-Movements of the Eyes N2 - Human visual perception is an active process. Eye movements either alternate between fixations and saccades or follow a smooth pursuit movement in case of moving targets. Besides these macroscopic gaze patterns, the eyes perform involuntary micro-movements during fixations which are commonly categorized into micro-saccades, drift and tremor. Eye movements are frequently studied in cognitive psychology, because they reflect a complex interplay of perception, attention and oculomotor control. A common insight of psychological research is that macro-movements are highly individual. Inspired by this finding, there has been a considerable amount of prior research on oculomotoric biometric identification. However, the accuracy of known approaches is too low and the time needed for identification is too long for any practical application. This thesis explores discriminative models for the task of biometric identification. Discriminative models optimize a quality measure of the predictions and are usually superior to generative approaches in discriminative tasks. However, using discriminative models requires to select a suitable form of data representation for sequential eye gaze data; i.e., by engineering features or constructing a sequence kernel and the performance of the classification model strongly depends on the data representation. We study two fundamentally different ways of representing eye gaze within a discriminative framework. In the first part of this thesis, we explore the integration of data and psychological background knowledge in the form of generative models to construct representations. To this end, we first develop generative statistical models of gaze behavior during reading and scene viewing that account for viewer-specific distributional properties of gaze patterns. In a second step, we develop a discriminative identification model by deriving Fisher kernel functions from these and several baseline models. We find that an SVM with Fisher kernel is able to reliably identify users based on their eye gaze during reading and scene viewing. However, since the generative models are constrained to use low-frequency macro-movements, they discard a significant amount of information contained in the raw eye tracking signal at a high cost: identification requires about one minute of input recording, which makes it inapplicable for real world biometric systems. In the second part of this thesis, we study a purely data-driven modeling approach. Here, we aim at automatically discovering the individual pattern hidden in the raw eye tracking signal. To this end, we develop a deep convolutional neural network DeepEyedentification that processes yaw and pitch gaze velocities and learns a representation end-to-end. Compared to prior work, this model increases the identification accuracy by one order of magnitude and the time to identification decreases to only seconds. The DeepEyedentificationLive model further improves upon the identification performance by processing binocular input and it also detects presentation-attacks. We find that by learning a representation, the performance of oculomotoric identification and presentation-attack detection can be driven close to practical relevance for biometric applications. Eye tracking devices with high sampling frequency and precision are expensive and the applicability of eye movement as a biometric feature heavily depends on cost of recording devices. In the last part of this thesis, we therefore study the requirements on data quality by evaluating the performance of the DeepEyedentificationLive network under reduced spatial and temporal resolution. We find that the method still attains a high identification accuracy at a temporal resolution of only 250 Hz and a precision of 0.03 degrees. Reducing both does not have an additive deteriorating effect. KW - Machine Learning Y1 - 2021 ER - TY - JOUR A1 - Gautam, Khem Raj A1 - Zhang, Guoqiang A1 - Landwehr, Niels A1 - Adolphs, Julian T1 - Machine learning for improvement of thermal conditions inside a hybrid ventilated animal building JF - Computers and electronics in agriculture : COMPAG online ; an international journal N2 - In buildings with hybrid ventilation, natural ventilation opening positions (windows), mechanical ventilation rates, heating, and cooling are manipulated to maintain desired thermal conditions. The indoor temperature is regulated solely by ventilation (natural and mechanical) when the external conditions are favorable to save external heating and cooling energy. The ventilation parameters are determined by a rule-based control scheme, which is not optimal. This study proposes a methodology to enable real-time optimum control of ventilation parameters. We developed offline prediction models to estimate future thermal conditions from the data collected from building in operation. The developed offline model is then used to find the optimal controllable ventilation parameters in real-time to minimize the setpoint deviation in the building. With the proposed methodology, the experimental building's setpoint deviation improved for 87% of time, on average, by 0.53 degrees C compared to the current deviations. KW - Animal building KW - Natural ventilation KW - Automatically controlled windows KW - Machine learning KW - Optimization Y1 - 2021 U6 - https://doi.org/10.1016/j.compag.2021.106259 SN - 0168-1699 SN - 1872-7107 VL - 187 PB - Elsevier Science CY - Amsterdam [u.a.] ER - TY - CHAP T1 - 11. Workshop Testmethoden und Zuverlässigkeit von Schaltungen und Systemen BT - vom 28. Februar bis 2. März, Potsdam-Hermannswerder, Inselhotel Y1 - 1999 SN - 978-3-9806494-1-4 PB - Universitätsverlag Potsdam CY - Potsdam ER - TY - THES A1 - Grütze, Toni T1 - Adding value to text with user-generated content N2 - In recent years, the ever-growing amount of documents on the Web as well as in closed systems for private or business contexts led to a considerable increase of valuable textual information about topics, events, and entities. It is a truism that the majority of information (i.e., business-relevant data) is only available in unstructured textual form. The text mining research field comprises various practice areas that have the common goal of harvesting high-quality information from textual data. These information help addressing users' information needs. In this thesis, we utilize the knowledge represented in user-generated content (UGC) originating from various social media services to improve text mining results. These social media platforms provide a plethora of information with varying focuses. In many cases, an essential feature of such platforms is to share relevant content with a peer group. Thus, the data exchanged in these communities tend to be focused on the interests of the user base. The popularity of social media services is growing continuously and the inherent knowledge is available to be utilized. We show that this knowledge can be used for three different tasks. Initially, we demonstrate that when searching persons with ambiguous names, the information from Wikipedia can be bootstrapped to group web search results according to the individuals occurring in the documents. We introduce two models and different means to handle persons missing in the UGC source. We show that the proposed approaches outperform traditional algorithms for search result clustering. Secondly, we discuss how the categorization of texts according to continuously changing community-generated folksonomies helps users to identify new information related to their interests. We specifically target temporal changes in the UGC and show how they influence the quality of different tag recommendation approaches. Finally, we introduce an algorithm to attempt the entity linking problem, a necessity for harvesting entity knowledge from large text collections. The goal is the linkage of mentions within the documents with their real-world entities. A major focus lies on the efficient derivation of coherent links. For each of the contributions, we provide a wide range of experiments on various text corpora as well as different sources of UGC. The evaluation shows the added value that the usage of these sources provides and confirms the appropriateness of leveraging user-generated content to serve different information needs. N2 - Die steigende Zahl an Dokumenten, welche in den letzten Jahren im Web sowie in geschlossenen Systemen aus dem privaten oder geschäftlichen Umfeld erstellt wurden, führte zu einem erheblichen Zuwachs an wertvollen Informationen über verschiedenste Themen, Ereignisse, Organisationen und Personen. Die meisten Informationen liegen lediglich in unstrukturierter, textueller Form vor. Das Forschungsgebiet des "Text Mining" befasst sich mit dem schwierigen Problem, hochwertige Informationen in strukturierter Form aus Texten zu gewinnen. Diese Informationen können dazu eingesetzt werden, Nutzern dabei zu helfen, ihren Informationsbedarf zu stillen. In dieser Arbeit nutzen wir Wissen, welches in nutzergenerierten Inhalten verborgen ist und aus unterschiedlichsten sozialen Medien stammt, um Text Mining Ergebnisse zu verbessern. Soziale Medien bieten eine Fülle an Informationen mit verschiedenen Schwerpunkten. Eine wesentliche Funktion solcher Medien ist es, den Nutzern zu ermöglichen, Inhalte mit ihrer Interessensgruppe zu teilen. Somit sind die ausgetauschten Daten in diesen Diensten häufig auf die Interessen der Nutzerbasis ausgerichtet. Die Popularität sozialer Medien wächst stetig und führt dazu, dass immer mehr inhärentes Wissen verfügbar wird. Dieses Wissen kann unter anderem für drei verschiedene Aufgabenstellungen genutzt werden. Zunächst zeigen wir, dass Informationen aus Wikipedia hilfreich sind, um Ergebnisse von Personensuchen im Web nach den in ihnen diskutierten Personen aufzuteilen. Dazu führen wir zwei Modelle zur Gruppierung der Ergebnisse und verschiedene Methoden zum Umgang mit fehlenden Wikipedia Einträgen ein, und zeigen, dass die entwickelten Ansätze traditionelle Methoden zur Gruppierung von Suchergebnissen übertreffen. Des Weiteren diskutieren wir, wie die Klassifizierung von Texten auf Basis von "Folksonomien" Nutzern dabei helfen kann, neue Informationen zu identifizieren, die ihren Interessen entsprechen. Wir konzentrieren uns insbesondere auf temporäre Änderungen in den nutzergenerierten Inhalten, um zu zeigen, wie stark ihr Einfluss auf die Qualität verschiedener "Tag"-Empfehlungsmethoden ist. Zu guter Letzt führen wir einen Algorithmus ein, der es ermöglicht, Nennungen von Echtweltinstanzen in Texten zu disambiguieren und mit ihren Repräsentationen in einer Wissensdatenbank zu verknüpfen. Das Hauptaugenmerk liegt dabei auf der effizienten Erkennung von kohärenten Verknüpfungen. Wir stellen für jeden Teil der Arbeit eine große Vielfalt an Experimenten auf diversen Textkorpora und unterschiedlichen Quellen von nutzergenerierten Inhalten an. Damit heben wir das Potential hervor, das die Nutzung jener Quellen bietet, um die unterschiedlichen Informationsbedürfnisse abzudecken. T2 - Mehrwert für Texte mittels nutzergenerierter Inhalte KW - nutzergenerierte Inhalte KW - text mining KW - Klassifikation KW - Clusteranalyse KW - Entitätsverknüpfung KW - user-generated content KW - text mining KW - classification KW - clustering KW - entity linking Y1 - 2018 ER - TY - JOUR A1 - Borchert, Florian A1 - Mock, Andreas A1 - Tomczak, Aurelie A1 - Hügel, Jonas A1 - Alkarkoukly, Samer A1 - Knurr, Alexander A1 - Volckmar, Anna-Lena A1 - Stenzinger, Albrecht A1 - Schirmacher, Peter A1 - Debus, Jürgen A1 - Jäger, Dirk A1 - Longerich, Thomas A1 - Fröhling, Stefan A1 - Eils, Roland A1 - Bougatf, Nina A1 - Sax, Ulrich A1 - Schapranow, Matthieu-Patrick T1 - Correction to: Knowledge bases and software support for variant interpretation in precision oncology JF - Briefings in bioinformatics Y1 - 2021 U6 - https://doi.org/10.1093/bib/bbab246 SN - 1467-5463 SN - 1477-4054 VL - 22 IS - 6 PB - Oxford Univ. Press CY - Oxford ER - TY - JOUR A1 - Ihde, Sven A1 - Pufahl, Luise A1 - Völker, Maximilian A1 - Goel, Asvin A1 - Weske, Mathias T1 - A framework for modeling and executing task BT - specific resource allocations in business processes JF - Computing : archives for informatics and numerical computation N2 - As resources are valuable assets, organizations have to decide which resources to allocate to business process tasks in a way that the process is executed not only effectively but also efficiently. Traditional role-based resource allocation leads to effective process executions, since each task is performed by a resource that has the required skills and competencies to do so. However, the resulting allocations are typically not as efficient as they could be, since optimization techniques have yet to find their way in traditional business process management scenarios. On the other hand, operations research provides a rich set of analytical methods for supporting problem-specific decisions on resource allocation. This paper provides a novel framework for creating transparency on existing tasks and resources, supporting individualized allocations for each activity in a process, and the possibility to integrate problem-specific analytical methods of the operations research domain. To validate the framework, the paper reports on the design and prototypical implementation of a software architecture, which extends a traditional process engine with a dedicated resource management component. This component allows us to define specific resource allocation problems at design time, and it also facilitates optimized resource allocation at run time. The framework is evaluated using a real-world parcel delivery process. The evaluation shows that the quality of the allocation results increase significantly with a technique from operations research in contrast to the traditional applied rule-based approach. KW - Process Execution KW - Business Process Management KW - Resource Allocation KW - Resource Management KW - Activity-oriented Optimization Y1 - 2022 U6 - https://doi.org/10.1007/s00607-022-01093-2 SN - 0010-485X SN - 1436-5057 VL - 104 SP - 2405 EP - 2429 PB - Springer CY - Wien ER - TY - GEN A1 - Combi, Carlo A1 - Oliboni, Barbara A1 - Weske, Mathias A1 - Zerbato, Francesca ED - Trujillo, JC Davis T1 - Conceptual modeling of processes and data BT - Connecting different perspectives T2 - Conceptual Modeling, ER 2018 N2 - Business processes constantly generate, manipulate, and consume data that are managed by organizational databases. Despite being central to process modeling and execution, the link between processes and data is often handled by developers when the process is implemented, thus leaving the connection unexplored during the conceptual design. In this paper, we introduce, formalize, and evaluate a novel conceptual view that bridges the gap between process and data models, and show some kinds of interesting insights that can be derived from this novel proposal. Y1 - 2018 SN - 978-3-030-00847-5 SN - 978-3-030-00846-8 U6 - https://doi.org/10.1007/978-3-030-00847-5_18 SN - 0302-9743 SN - 1611-3349 VL - 11157 SP - 236 EP - 250 PB - Springer CY - Cham ER - TY - CHAP A1 - Gonnermann, Jana A1 - Teichmann, Malte T1 - Influence of pre-experience on learning, usability and cognitive load in a virtual learning environment T2 - Americas conference on information systems N2 - Virtual reality can have advantages for education and learning. However, it must be adequately designed so that the learner benefits from the technological possibilities. Understanding the underlying effects of the virtual learning environment and the learner’s prior experience with virtual reality or prior knowledge of the content is necessary to design a proper virtual learning environment. This article presents a pre-study testing the design of a virtual learning environment for engineering vocational training courses. In the pre-study, 12 employees of two companies joined the training course in one of the two degrees of immersion (desktop VR and VR HMD). Quantitative results on learning success, cognitive load, usability, and motivation and qualitative learning process data were presented. The qualitative data assessment shows that overall, the employees were satisfied with the learning environment regardless of the level of immersion and that the participants asked for more guidance and structure accompanying the learning process. Further research is needed to test for solid group differences. KW - immersion KW - virtual learning environments KW - learner characteristics KW - vocational training KW - cognitive load theory Y1 - 2023 UR - https://aisel.aisnet.org/amcis2023/sig_ed/sig_ed/25/ IS - 1871 PB - AIS CY - Atlanta ER -