@inproceedings{LeiseAltherrPelz2018, author = {Leise, Philipp and Altherr, Lena and Pelz, Peter F.}, title = {Technical Operations Research (TOR) - Algorithms, not Engineers, Design Optimal Energy Efficient and Resilient Cooling Systems}, series = {FAN2018 - Proceedings of the International Conference on Fan Noise, Aerodynamics, Applications and Systems}, booktitle = {FAN2018 - Proceedings of the International Conference on Fan Noise, Aerodynamics, Applications and Systems}, pages = {1 -- 12}, year = {2018}, abstract = {The overall energy efficiency of ventilation systems can be improved by considering not only single components, but by considering as well the interplay between every part of the system. With the help of the method "TOR" ("Technical Operations Research"), which was developed at the Chair of Fluid Systems at TU Darmstadt, it is possible to improve the energy efficiency of the whole system by considering all possible design choices programmatically. We show the ability of this systematic design approach with a ventilation system for buildings as a use case example. Based on a Mixed-Integer Nonlinear Program (MINLP) we model the ventilation system. We use binary variables to model the selection of different pipe diameters. Multiple fans are model with the help of scaling laws. The whole system is represented by a graph, where the edges represent the pipes and fans and the nodes represents the source of air for cooling and the sinks, that have to be cooled. At the beginning, the human designer chooses a construction kit of different suitable fans and pipes of different diameters and different load cases. These boundary conditions define a variety of different possible system topologies. It is not possible to consider all topologies by hand. With the help of state of the art solvers, on the other side, it is possible to solve this MINLP. Next to this, we also consider the effects of malfunctions in different components. Therefore, we show a first approach to measure the resilience of the shown example use case. Further, we compare the conventional approach with designs that are more resilient. These more resilient designs are derived by extending the before mentioned model with further constraints, that consider explicitly the resilience of the overall system. We show that it is possible to design resilient systems with this method already in the early design stage and compare the energy efficiency and resilience of these different system designs.}, language = {en} } @inproceedings{AltherrPelzEdereretal.2017, author = {Altherr, Lena and Pelz, Peter F. and Ederer, Thorsten and Pfetsch, Marc E.}, title = {Optimale Getriebe auf Knopfdruck: Gemischt-ganzzahlige nichtlineare Optimierung zur Entscheidungsunterst{\"u}tzung bei der Auslegung von Getrieben f{\"u}r Kraftfahrzeuge}, series = {Antriebstechnisches Kolloquium ATK 2017}, booktitle = {Antriebstechnisches Kolloquium ATK 2017}, editor = {Jacobs, Georg}, isbn = {9783743148970}, pages = {313 -- 325}, year = {2017}, language = {de} } @inproceedings{RauschFriesenAltherretal.2018, author = {Rausch, Lea and Friesen, John and Altherr, Lena and Pelz, Peter F.}, title = {Using mixed-integer programming for the optimal design of water supply networks for slums}, series = {Operations Research Proceedings 2017}, booktitle = {Operations Research Proceedings 2017}, editor = {Kliewer, Natalia and Ehmke, Jan Fabian and Bornd{\"o}rfer, Ralf}, publisher = {Springer}, address = {Cham}, isbn = {978-3-319-89919-0 (Print)}, doi = {10.1007/978-3-319-89920-6_68}, pages = {509 -- 516}, year = {2018}, abstract = {The UN sets the goal to ensure access to water and sanitation for all people by 2030. To address this goal, we present a multidisciplinary approach for designing water supply networks for slums in large cities by applying mathematical optimization. The problem is modeled as a mixed-integer linear problem (MILP) aiming to find a network describing the optimal supply infrastructure. To illustrate the approach, we apply it on a small slum cluster in Dhaka, Bangladesh.}, language = {en} } @inproceedings{RauschLeiseEdereretal.2016, author = {Rausch, Lea and Leise, Philipp and Ederer, Thorsten and Altherr, Lena and Pelz, Peter F.}, title = {A comparison of MILP and MINLP solver performance on the example of a drinking water supply system design problem}, series = {ECCOMAS Congress 2016 VII European Congress on Computational Methods in Applied Sciences and Engineering}, booktitle = {ECCOMAS Congress 2016 VII European Congress on Computational Methods in Applied Sciences and Engineering}, editor = {Papadrakakis, M. and Ppadopoulos, V. and Stefanou, G. and Plevris, V.}, isbn = {978-618-82844-0-1}, pages = {8509 -- 8527}, year = {2016}, abstract = {Finding a good system topology with more than a handful of components is a highly non-trivial task. The system needs to be able to fulfil all expected load cases, but at the same time the components should interact in an energy-efficient way. An example for a system design problem is the layout of the drinking water supply of a residential building. It may be reasonable to choose a design of spatially distributed pumps which are connected by pipes in at least two dimensions. This leads to a large variety of possible system topologies. To solve such problems in a reasonable time frame, the nonlinear technical characteristics must be modelled as simple as possible, while still achieving a sufficiently good representation of reality. The aim of this paper is to compare the speed and reliability of a selection of leading mathematical programming solvers on a set of varying model formulations. This gives us empirical evidence on what combinations of model formulations and solver packages are the means of choice with the current state of the art.}, language = {en} } @inproceedings{MuellerAltherrAholaetal.2019, author = {M{\"u}ller, Tim M. and Altherr, Lena and Ahola, Marja and Schabel, Samuel and Pelz, Peter F.}, title = {Multi-Criteria optimization of pressure screen systems in paper recycling - balancing quality, yield, energy consumption and system complexity}, series = {EngOpt 2018 Proceedings of the 6th International Conference on Engineering Optimization}, booktitle = {EngOpt 2018 Proceedings of the 6th International Conference on Engineering Optimization}, editor = {Rodrigues, H. C.}, publisher = {Springer International Publishing}, address = {Basel}, isbn = {978-3-319-97773-7}, doi = {10.1007/978-3-319-97773-7_105}, year = {2019}, abstract = {The paper industry is the industry with the third highest energy consumption in the European Union. Using recycled paper instead of fresh fibers for papermaking is less energy consuming and saves resources. However, adhesive contaminants in recycled paper are particularly problematic since they reduce the quality of the resulting paper-product. To remove as many contaminants and at the same time obtain as many valuable fibres as possible, fine screening systems, consisting of multiple interconnected pressure screens, are used. Choosing the best configuration is a non-trivial task: The screens can be interconnected in several ways, and suitable screen designs as well as operational parameters have to be selected. Additionally, one has to face conflicting objectives. In this paper, we present an approach for the multi-criteria optimization of pressure screen systems based on Mixed-Integer Nonlinear Programming. We specifically focus on a clear representation of the trade-off between different objectives.}, language = {en} } @inproceedings{AltherrEdererSchaenzleetal.2017, author = {Altherr, Lena and Ederer, Thorsten and Sch{\"a}nzle, Christian and Lorenz, Ulf and Pelz, Peter F.}, title = {Algorithmic system design using scaling and affinity laws}, series = {Operations Research Proceedings 2015}, booktitle = {Operations Research Proceedings 2015}, publisher = {Springer}, address = {Cham}, isbn = {978-3-319-42901-4}, doi = {10.1007/978-3-319-42902-1}, pages = {605 -- 611}, year = {2017}, abstract = {Energy-efficient components do not automatically lead to energy-efficient systems. Technical Operations Research (TOR) shifts the focus from the single component to the system as a whole and finds its optimal topology and operating strategy simultaneously. In previous works, we provided a preselected construction kit of suitable components for the algorithm. This approach may give rise to a combinatorial explosion if the preselection cannot be cut down to a reasonable number by human intuition. To reduce the number of discrete decisions, we integrate laws derived from similarity theory into the optimization model. Since the physical characteristics of a production series are similar, it can be described by affinity and scaling laws. Making use of these laws, our construction kit can be modeled more efficiently: Instead of a preselection of components, it now encompasses whole model ranges. This allows us to significantly increase the number of possible set-ups in our model. In this paper, we present how to embed this new formulation into a mixed-integer program and assess the run time via benchmarks. We present our approach on the example of a ventilation system design problem.}, language = {en} } @inproceedings{AltherrEdererVergeetal.2015, author = {Altherr, Lena and Ederer, Thorsten and Verg{\´e}, Angela and Pelz, Peter F.}, title = {Algorithmische Struktursynthese eines hydrostatischen Getriebes}, series = {Antriebssysteme 2015 : Elektrik, Mechanik, Fluidtechnik in der Anwendung}, booktitle = {Antriebssysteme 2015 : Elektrik, Mechanik, Fluidtechnik in der Anwendung}, publisher = {VDI-Verlag}, address = {D{\"u}sseldorf}, isbn = {978-3-18-092268-3}, pages = {145 -- 155}, year = {2015}, language = {de} } @inproceedings{SchaenzleAltherrEdereretal.2015, author = {Sch{\"a}nzle, Christian and Altherr, Lena and Ederer, Thorsten and Lorenz, Ulf and Pelz, Peter F.}, title = {As good as it can be: Ventilation system design by a combined scaling and discrete optimization method}, series = {Proceedings of FAN 2015}, booktitle = {Proceedings of FAN 2015}, pages = {1 -- 11}, year = {2015}, abstract = {The understanding that optimized components do not automatically lead to energy-efficient systems sets the attention from the single component on the entire technical system. At TU Darmstadt, a new field of research named Technical Operations Research (TOR) has its origin. It combines mathematical and technical know-how for the optimal design of technical systems. We illustrate our optimization approach in a case study for the design of a ventilation system with the ambition to minimize the energy consumption for a temporal distribution of diverse load demands. By combining scaling laws with our optimization methods we find the optimal combination of fans and show the advantage of the use of multiple fans.}, language = {en} } @inproceedings{AltherrEdererFarnetaneetal.2017, author = {Altherr, Lena and Ederer, Thorsten and Farnetane, Lucas S. and P{\"o}ttgen, Philipp and Verg{\´e}, Angela and Pelz, Peter F.}, title = {Multicriterial design of a hydrostatic transmission system via mixed-integer programming}, series = {Operations Research Proceedings 2015}, booktitle = {Operations Research Proceedings 2015}, publisher = {Springer}, address = {Cham}, isbn = {978-3-319-42901-4}, doi = {10.1007/978-3-319-42902-1_41}, pages = {301 -- 307}, year = {2017}, abstract = {In times of planned obsolescence the demand for sustainability keeps growing. Ideally, a technical system is highly reliable, without failures and down times due to fast wear of single components. At the same time, maintenance should preferably be limited to pre-defined time intervals. Dispersion of load between multiple components can increase a system's reliability and thus its availability inbetween maintenance points. However, this also results in higher investment costs and additional efforts due to higher complexity. Given a specific load profile and resulting wear of components, it is often unclear which system structure is the optimal one. Technical Operations Research (TOR) finds an optimal structure balancing availability and effort. We present our approach by designing a hydrostatic transmission system.}, language = {en} } @inproceedings{OstkottePetersHueningetal.2022, author = {Ostkotte, Sebastian and Peters, Constantin and H{\"u}ning, Felix and Bragard, Michael}, title = {Design, implementation and verification of an rotational incremental position encoder based on the magnetic Wiegand effect}, series = {2022 ELEKTRO (ELEKTRO)}, booktitle = {2022 ELEKTRO (ELEKTRO)}, publisher = {IEEE}, isbn = {978-1-6654-6726-1}, issn = {2691-0616}, doi = {10.1109/ELEKTRO53996.2022.9803477}, pages = {6 Seiten}, year = {2022}, abstract = {This paper covers the use of the magnetic Wiegand effect to design an innovative incremental encoder. First, a theoretical design is given, followed by an estimation of the achievable accuracy and an optimization in open-loop operation. Finally, a successful experimental verification is presented. For this purpose, a permanent magnet synchronous machine is controlled in a field-oriented manner, using the angle information of the prototype.}, language = {en} } @inproceedings{BeckerHoefkenSchuetzetal.2016, author = {Becker, Sebastian and H{\"o}fken, Hans-Wilhelm and Sch{\"u}tz, Philip and Schuba, Marko}, title = {IT-forensische Erkennung modifizierter Android-Apps}, series = {Proceedings of DACH Security 2016, Klagenfurt, Austria, September 2016}, booktitle = {Proceedings of DACH Security 2016, Klagenfurt, Austria, September 2016}, editor = {Schartner, P.}, pages = {120 -- 125}, year = {2016}, abstract = {Malware auf Smartphones ist ein Problem, dem auch Strafverfolgungsbeh{\"o}rden immer h{\"a}ufiger gegen{\"u}berstehen. Insbesondere Telefone, bei denen potentiell schadhafte Apps zu einem finanziellen Schaden gef{\"u}hrt haben, finden sich auf den Schreibtischen der Polizei wieder. Dabei m{\"u}ssen die Ermittler m{\"o}glichst schnell und gezielt erkennen k{\"o}nnen, ob eine App tats{\"a}chlich schadhaft manipuliert wurde, was manipuliert wurde und mit wem die App kommuniziert. Klassische Malware-Erkennungsverfahren helfen zwar bei der generellen Erkennung schadhafter Software, sind aber f{\"u}r die polizeiliche Praxis nicht geeignet. Dieses Paper stellt ein Programm vor, welches gerade die forensischen Fragestellungen ber{\"u}cksichtigt und so f{\"u}r den Einsatz in der Strafverfolgung in Frage kommt.}, language = {de} } @inproceedings{BonneyNagelSchuba2016, author = {Bonney, Gregor and Nagel, Stefan and Schuba, Marko}, title = {Risiko Smart Home - Angriff auf ein Babymonitorsystem}, series = {Proceedings of DACH Security 2016, Klagenfurt, Austria, September 2016}, booktitle = {Proceedings of DACH Security 2016, Klagenfurt, Austria, September 2016}, editor = {Schartner, P.}, pages = {371 -- 378}, year = {2016}, abstract = {Unser Zuhause wird zunehmend intelligenter. Smart Homes bieten uns die Steuerung von Haus- oder Unterhaltungstechnik bequem vom Smartphone aus. Junge Familien nutzen die Technologie, um mittels vernetzten Babymonitorsystemen ihren Nachwuchs von {\"u}berall aus im Blick zu haben. Davon auszugehen, dass solche Systeme mit einem Fokus auf Sicherheit entwickelt wurden, um die sehr pers{\"o}nlichen Daten zu sch{\"u}tzen, ist jedoch ein Trugschluss. Die Untersuchung eines handels{\"u}blichen und keineswegs billigen Systems zeigt, dass die Ger{\"a}te sehr einfach kompromittiert und missbraucht werden k{\"o}nnen.}, language = {de} } @inproceedings{LorenzAltherrPelz2020, author = {Lorenz, Imke-Sophie and Altherr, Lena and Pelz, Peter F.}, title = {Resilience enhancement of critical infrastructure - graph-theoretical resilience analysis of the water distribution system in the German city of Darmstadt}, series = {14th WCEAM Proceedings}, booktitle = {14th WCEAM Proceedings}, publisher = {Springer}, address = {Cham}, isbn = {978-3-030-64228-0}, doi = {10.1007/978-3-030-64228-0_13}, pages = {137 -- 149}, year = {2020}, abstract = {Water suppliers are faced with the great challenge of achieving high-quality and, at the same time, low-cost water supply. Since climatic and demographic influences will pose further challenges in the future, the resilience enhancement of water distribution systems (WDS), i.e. the enhancement of their capability to withstand and recover from disturbances, has been in particular focus recently. To assess the resilience of WDS, graph-theoretical metrics have been proposed. In this study, a promising approach is first physically derived analytically and then applied to assess the resilience of the WDS for a district in a major German City. The topology based resilience index computed for every consumer node takes into consideration the resistance of the best supply path as well as alternative supply paths. This resistance of a supply path is derived to be the dimensionless pressure loss in the pipes making up the path. The conducted analysis of a present WDS provides insight into the process of actively influencing the resilience of WDS locally and globally by adding pipes. The study shows that especially pipes added close to the reservoirs and main branching points in the WDS result in a high resilience enhancement of the overall WDS.}, language = {en} } @inproceedings{SchaenzleAltherrEdereretal.2015, author = {Sch{\"a}nzle, Christian and Altherr, Lena and Ederer, Thorsten and Pelz, Peter}, title = {TOR - Towards the energetically optimal ventilation system}, pages = {1 Seite}, year = {2015}, language = {en} } @inproceedings{NikolovskiRekeElsenetal.2021, author = {Nikolovski, Gjorgji and Reke, Michael and Elsen, Ingo and Schiffer, Stefan}, title = {Machine learning based 3D object detection for navigation in unstructured environments}, series = {2021 IEEE Intelligent Vehicles Symposium Workshops (IV Workshops)}, booktitle = {2021 IEEE Intelligent Vehicles Symposium Workshops (IV Workshops)}, publisher = {IEEE}, isbn = {978-1-6654-7921-9}, doi = {10.1109/IVWorkshops54471.2021.9669218}, pages = {236 -- 242}, year = {2021}, abstract = {In this paper we investigate the use of deep neural networks for 3D object detection in uncommon, unstructured environments such as in an open-pit mine. While neural nets are frequently used for object detection in regular autonomous driving applications, more unusual driving scenarios aside street traffic pose additional challenges. For one, the collection of appropriate data sets to train the networks is an issue. For another, testing the performance of trained networks often requires tailored integration with the particular domain as well. While there exist different solutions for these problems in regular autonomous driving, there are only very few approaches that work for special domains just as well. We address both the challenges above in this work. First, we discuss two possible ways of acquiring data for training and evaluation. That is, we evaluate a semi-automated annotation of recorded LIDAR data and we examine synthetic data generation. Using these datasets we train and test different deep neural network for the task of object detection. Second, we propose a possible integration of a ROS2 detector module for an autonomous driving platform. Finally, we present the performance of three state-of-the-art deep neural networks in the domain of 3D object detection on a synthetic dataset and a smaller one containing a characteristic object from an open-pit mine.}, language = {en} } @inproceedings{AmirBauckhageChircuetal.2022, author = {Amir, Malik and Bauckhage, Christian and Chircu, Alina and Czarnecki, Christian and Knopf, Christian and Piatkowski, Nico and Sultanow, Eldar}, title = {What can we expect from quantum (digital) twins?}, series = {Wirtschaftsinformatik 2022 Proceedings}, booktitle = {Wirtschaftsinformatik 2022 Proceedings}, publisher = {AIS Electronic Library (AISeL)}, pages = {1 -- 14}, year = {2022}, abstract = {Digital twins enable the modeling and simulation of real-world entities (objects, processes or systems), resulting in improvements in the associated value chains. The emerging field of quantum computing holds tremendous promise forevolving this virtualization towards Quantum (Digital) Twins (QDT) and ultimately Quantum Twins (QT). The quantum (digital) twin concept is not a contradiction in terms - but instead describes a hybrid approach that can be implemented using the technologies available today by combining classicalcomputing and digital twin concepts with quantum processing. This paperpresents the status quo of research and practice on quantum (digital) twins. It alsodiscuses their potential to create competitive advantage through real-timesimulation of highly complex, interconnected entities that helps companies better address changes in their environment and differentiate their products andservices.}, language = {en} } @inproceedings{RitschelStenzelCzarneckietal.2021, author = {Ritschel, Konstantin and Stenzel, Adina and Czarnecki, Christian and Hong, Chin-Gi}, title = {Realizing robotic process automation potentials: an architectural perspective on a real-life implementation case}, series = {GI Edition Proceedings Band 314 "INFORMATIK 2021" Computer Science \& Sustainability}, booktitle = {GI Edition Proceedings Band 314 "INFORMATIK 2021" Computer Science \& Sustainability}, editor = {Gesellschaft f{\"u}r Informatik e.V. (GI),}, publisher = {K{\"o}llen}, address = {Bonn}, isbn = {9783885797081}, issn = {1617-5468}, doi = {10.18420/informatik2021-108}, pages = {1303 -- 1311}, year = {2021}, abstract = {The initial idea of Robotic Process Automation (RPA) is the automation of business processes through a simple emulation of user input and output by software robots. Hence, it can be assumed that no changes of the used software systems and existing Enterprise Architecture (EA) is required. In this short, practical paper we discuss this assumption based on a real-life implementation project. We show that a successful RPA implementation might require architectural work during analysis, implementation, and migration. As practical paper we focus on exemplary lessons-learned and new questions related to RPA and EA.}, language = {en} } @inproceedings{AuthCzarneckiBensberg2019, author = {Auth, Gunnar and Czarnecki, Christian and Bensberg, Frank}, title = {Impact of robotic process automation on enterprise architectures}, series = {GI Edition Proceedings Band 295 INFORMATIK 2019, Workshop-Beitr{\"a}ge}, booktitle = {GI Edition Proceedings Band 295 INFORMATIK 2019, Workshop-Beitr{\"a}ge}, editor = {Draude, Claude and Lange, Martin and Sick, Bernhard and Gesellschaft f{\"u}r Informatik e.V. (GI),}, publisher = {K{\"o}llen}, address = {Bonn}, isbn = {9783885796893}, issn = {1617-5468}, doi = {10.18420/inf2019_ws05}, pages = {59 -- 65}, year = {2019}, abstract = {The initial idea of Robotic Process Automation (RPA) is the automation of business processes through the presentation layer of existing application systems. For this simple emulation of user input and output by software robots, no changes of the systems and architecture is required. However, considering strategic aspects of aligning business and technology on an enterprise level as well as the growing capabilities of RPA driven by artificial intelligence, interrelations between RPA and Enterprise Architecture (EA) become visible and pose new questions. In this paper we discuss the relationship between RPA and EA in terms of perspectives and implications. As workin- progress we focus on identifying new questions and research opportunities related to RPA and EA.}, language = {en} } @inproceedings{BrockmannSultanowCzarnecki2019, author = {Brockmann, Carsten and Sultanow, Eldar and Czarnecki, Christian}, title = {Is enterprise architecture still relevant in the digital age?}, series = {GI Edition Proceedings Band 295 INFORMATIK 2019, Workshop-Beitr{\"a}ge}, booktitle = {GI Edition Proceedings Band 295 INFORMATIK 2019, Workshop-Beitr{\"a}ge}, editor = {Draude, Claude and Lange, Martin and Sick, Bernhard}, publisher = {K{\"o}llen}, address = {Bonn}, isbn = {9783885796893}, issn = {1617-5468}, doi = {10.18420/inf2019_ws01}, pages = {21 -- 21}, year = {2019}, language = {en} } @inproceedings{BensbergAuthCzarneckietal.2018, author = {Bensberg, Frank and Auth, Gunnar and Czarnecki, Christian and W{\"o}rndle, Christopher}, title = {Transforming literature-intensive research processes through text analytics - design, implementation and lessons learned}, editor = {Kemal İlter, H.}, doi = {10.6084/m9.figshare.7582073.v1}, pages = {9 Seiten}, year = {2018}, abstract = {The continuing growth of scientific publications raises the question how research processes can be digitalized and thus realized more productively. Especially in information technology fields, research practice is characterized by a rapidly growing volume of publications. For the search process various information systems exist. However, the analysis of the published content is still a highly manual task. Therefore, we propose a text analytics system that allows a fully digitalized analysis of literature sources. We have realized a prototype by using EBSCO Discovery Service in combination with IBM Watson Explorer and demonstrated the results in real-life research projects. Potential addressees are research institutions, consulting firms, and decision-makers in politics and business practice.}, language = {en} } @inproceedings{BrockmannSultanowCzarnecki2018, author = {Brockmann, Carsten and Sultanow, Eldar and Czarnecki, Christian}, title = {Enterprise architectures between agility and traditional methodologies}, series = {GI Edition Proceedings Band 285 Workshops der INFORMATIK 2018}, booktitle = {GI Edition Proceedings Band 285 Workshops der INFORMATIK 2018}, editor = {Czarnecki, Christian and Brockmann, Carsten and Sultanow, Eldar and Koschmider, Agnes and Selzer, Annika and Gesellschaft f{\"u}r Informatik e. V.,}, publisher = {K{\"o}llen}, address = {Bonn}, isbn = {9783885796794}, issn = {1617-5468}, pages = {1 Seite}, year = {2018}, abstract = {For this year's workshop on Enterpirse Architecture in Research and Practice we have received eight submissions from which four have passed the rigorous peer-review. The acceptance quote of 50\% assures that only advancements in the field are included in our workshop.}, language = {en} } @inproceedings{SchnejiderWisselinkCzarnecki2017, author = {Schnejider, Dominik and Wisselink, Frank and Czarnecki, Christian}, title = {Transformation von Wertsch{\"o}pfungsketten durch das Internet der Dinge - Bewertungsrahmen und Fallstudie}, series = {GI Edition Proceedings Band 275 INFORMATIK 2017}, booktitle = {GI Edition Proceedings Band 275 INFORMATIK 2017}, editor = {Eibl, Maximilian and Gaedke, Martin and Gesellschaft f{\"u}r Informatik e. V. (GI),}, publisher = {K{\"o}llen}, address = {Bonn}, isbn = {978-3-88579-669-5}, issn = {1617-5468}, doi = {10.18420/in2017_208}, pages = {2081 -- 2094}, year = {2017}, abstract = {Momentan finden in vielen Branchen umfassende Ver{\"a}nderungen von M{\"a}rkten und Wertsch{\"o}pfungsketten statt, welche auch als Digitale Transformation bezeichnet werden. In diesem Zusammenhang wird das Internet der Dinge (Internet of Things, IoT) als ein wichtiger technischer Enabler der Ver{\"a}nderungen angesehen. Prim{\"a}re Ziele des IoT sind die Steuerung physischer Gegen-st{\"a}nde aus der Distanz und das Erfassen von Informationen aus dem Umfeld dieser Gegenst{\"a}nde. Welche neuen Gesch{\"a}fts-bzw. Partnermodelle entstehen durch die gemeinsame Nutzung von IoT-Daten und Big-Data-Technologien und welcher qualitative Mehrwert wird dadurch geschaffen? Als Antwort wird in diesem Beitrag ein Bewertungsrahmen zur qualitativen Wertsch{\"o}pfungsanalyse von IoT vorgeschlagen. Anhand dieses Bewertungsrahmens wird ein Anwendungsfall untersucht, der in anonymisierter Form an konkrete Praxisprojekte angelehnt ist. Konkret wird ein Anwendungsfall betrachtet, der eine Abfallwirtschaft 2.0 basierend auf dem Einsatz von IoT vorschl{\"a}gt. Aus den Untersuchungsergebnissen gehen beispielsweise Erkenntnisse hervor, wie Gesch{\"a}ftsmodelle auf Basis eines unentgeltlichen Informationsaustauschs durch IoT gestaltet werden k{\"o}nnen.}, language = {de} } @inproceedings{ThomeCzarneckiAuthetal.2017, author = {Thom{\´e}, Tristan Eberhard and Czarnecki, Christian and Auth, Gunnar and Bensberg, Frank}, title = {Erweiterung des Referenzprozessmodells eTOM um die Anforderungen des deutschen IT-Sicherheitsgesetzes}, series = {Prozesse, Technologie, Anwendungen, Systeme und Management 2017. Angewandte Forschung in der Wirtschaftsinformatik}, booktitle = {Prozesse, Technologie, Anwendungen, Systeme und Management 2017. Angewandte Forschung in der Wirtschaftsinformatik}, editor = {Barton, Thomas and Herrmann, Frank and Meister, Vera G. and M{\"u}ller, Christian and Seel, Christian}, publisher = {mana-Buch}, address = {Heide}, isbn = {978-3-944330-56-3}, pages = {51 -- 60}, year = {2017}, abstract = {Kritische Infrastrukturen sind prim{\"a}re Ziele krimineller Hacker. Der Deutsche Bundestag reagierte darauf am 25. Juli 2015 mit einem Gesetz zur Verbesserung der Sicherheit von ITSystemen, dem IT-Sicherheitsgesetz. Dies verlangt von Betreibern kritischer Infrastrukturen, angemessene Mindeststandards f{\"u}r organisatorische und technische Sicherheit zu implementieren, um den Betrieb und die Verf{\"u}gbarkeit dieser Infrastruktur zu gew{\"a}hrleisten. Telekommunikationsunternehmen sind einerseits von diesem Gesetz in besonderem Maße betroffen und verf{\"u}gen andererseits mit dem Rahmenwerk enhanced Telecom Operations Map (eTOM) {\"u}ber ein international anerkanntes Referenzmodell zur Gestaltung von Gesch{\"a}ftsprozessen in dieser Branche. Da s{\"a}mtliche Telekommunikationsunternehmen in Deutschland verpflichtet sind, das Gesetz innerhalb eines bestimmten Zeitrahmens zu implementieren, pr{\"a}sentiert dieser Beitrag einen Vorschlag zur Erweiterung von eTOM um die relevanten Anforderungen des deutschen IT-Sicherheitsgesetzes.}, language = {de} } @inproceedings{SchneiderWisselinkCzarnecki2017, author = {Schneider, Dominik and Wisselink, Frank and Czarnecki, Christian}, title = {Qualitative Wertsch{\"o}pfungsanalyse von Anwendungsf{\"a}llen des Narrowband Internet of Things}, series = {Prozesse, Technologie, Anwendungen, Systeme und Management 2017. Angewandte Forschung in der Wirtschaftsinformatik}, booktitle = {Prozesse, Technologie, Anwendungen, Systeme und Management 2017. Angewandte Forschung in der Wirtschaftsinformatik}, editor = {Barton, Thomas and Herrmann, Frank and Meister, Vera G. and M{\"u}ller, Christian and Seel, Christian}, publisher = {mana-Buch}, address = {Heide}, isbn = {978-3-944330-56-3}, pages = {184 -- 193}, year = {2017}, abstract = {Prim{\"a}re Ziele des Internets der Dinge sind die Steuerung physischer Gegenst{\"a}nde aus der Distanz und das Erfassen von Informationen aus dem Umfeld dieser Gegenst{\"a}nde. Dazu werden Hardwarekomponenten in Gegenst{\"a}nde des t{\"a}glichen Lebens und die Umwelt integriert. Mithilfe von Informations- und Kommunikationstechnologien entsteht hieraus das Internet der Dinge (Internet of Things, IoT). Vor einem Jahr wurde mit Narrowband Internet of Things (NB-IoT) eine Technologie die es erm{\"o}glicht, Hardwarekomponenten energieeffizient und unmittelbar {\"u}ber das Mobilfunknetz zu vernetzen. Gegenst{\"a}nde werden dadurch {\"u}ber große Reichweiten eigenst{\"a}ndig kommunikationsf{\"a}hig. Das IoT steht mit NB-IoT vor einem gestiegenen Nutzenpotenzial, da eine zunehmende Anzahl miteinander verbundener Gegenst{\"a}nde und der Austausch gr{\"o}ßerer Datenmengen realisierbar sind. Damit sind aus wirtschaftlicher Sicht neue, innovative Anwendungsf{\"a}lle des IoT m{\"o}glich, die auch bereits in der Praxis diskutiert werden. In diesem Beitrag wird anhand eines konkreten Anwendungsfalls untersucht, welche neuen Gesch{\"a}fts- bzw. Partnermodelle durch die gemeinsame Nutzung von NB-IoT-Daten und Big Data-Technologien entstehen und welcher qualitative Mehrwert f{\"u}r die an einem Anwendungsfall beteiligten Stakeholder geschaffen wird. Dazu wird - einem konstruktionsorientierten Forschungsansatz folgend - ein Bewertungsrahmen zur qualitativen Wertsch{\"o}pfungsanalyse von NB-IoT entwickelt, der u.a. auf der Schablone nach Cockburn und dem Business Model Canvas basiert. Anhand dieses Bewertungsrahmens wird ein Anwendungsfall untersucht, der in anonymisierter Form an konkrete Praxisprojekte angelehnt ist. Konkret wird ein Anwendungsfall betrachtet, der einen Fahrradverleih 2.0 basierend auf dem Einsatz von NB-IoT vorschl{\"a}gt. Aus den Untersuchungsergebnissen gehen beispielsweise Erkenntnisse hervor, wie Gesch{\"a}ftsmodelle auf}, language = {de} } @inproceedings{CzarneckiDietze2017, author = {Czarnecki, Christian and Dietze, Christian}, title = {Domain-Specific reference modeling in the telecommunications industry}, series = {DESRIST 2017: Designing the Digital Transformation}, booktitle = {DESRIST 2017: Designing the Digital Transformation}, editor = {Maedche, Alexander and vom Brocke, Jan and Hevner, Alan}, publisher = {Springer}, address = {Cham}, isbn = {978-3-319-59144-5}, doi = {10.1007/978-3-319-59144-5_19}, pages = {313 -- 329}, year = {2017}, abstract = {The telecommunications industry is currently going through a major transformation. In this context, the enhanced Telecom Operations Map (eTOM) is a domain-specific process reference model that is offered by the industry organization TM Forum. In practice, eTOM is well accepted and confirmed as de facto standard. It provides process definitions and process flows on different levels of detail. This article discusses the reference modeling of eTOM, i.e., the design, the resulting artifact, and its evaluation based on three project cases. The application of eTOM in three projects illustrates the design approach and concrete models on strategic and operational levels. The article follows the Design Science Research (DSR) paradigm. It contributes with concrete design artifacts to the transformational needs of the telecommunications industry and offers lessons-learned from a general DSR perspective.}, language = {en} } @inproceedings{Czarnecki2016, author = {Czarnecki, Christian}, title = {Design und Nutzung einer industriespezifischen Referenzarchitektur f{\"u}r die Telekommunikationsindustrie}, series = {GI Edition Proceedings Band 259 INFORMATIK 2016. 26.-30. September 2016 Klagenfurt}, booktitle = {GI Edition Proceedings Band 259 INFORMATIK 2016. 26.-30. September 2016 Klagenfurt}, editor = {Mayr, Heinrich C. and Pinzger, Martin and Gesellschaft f{\"u}r Informatik e. V. (GI),}, publisher = {K{\"o}llen}, address = {Bonn}, isbn = {9783885796534}, issn = {1617-5468}, pages = {807 -- 814}, year = {2016}, abstract = {Zur Unterst{\"u}tzung des Transformationsbedarfs von Telekommunikationsunternehmen sind die Referenzmodelle des TM Forums in der Praxis weltweit anerkannt. Dabei findet jedoch meist eine losgel{\"o}ste Nutzung f{\"u}r spezifische Einzelthemen statt. Daher f{\"u}hrt dieser Artikel die bestehenden Inhalte in einer industriespezifischen, {\"u}bergreifenden Referenzarchitektur zusammen. Der Fokus liegt auf den Ebenen Aufbauorganisation, Prozesse, Applikationen und Daten. Dar{\"u}ber hinaus werden inhaltliche Architekturdom{\"a}nen zur Strukturierung angeboten. Die Referenzarchitektur ist hierarchisch aufgebaut und wird hier beispielhaft f{\"u}r ausgew{\"a}hlte, aggregierte Inhalte beschrieben. Als erste Evaluation wird die Anwendung der Referenzarchitektur in drei Praxisprojekten erl{\"a}utert.}, language = {de} } @inproceedings{BensbergAuthCzarnecki2018, author = {Bensberg, Frank and Auth, Gunnar and Czarnecki, Christian}, title = {Unterst{\"u}tzung von Wissenstransferprozessen durch Erschließung von Literaturdatenbanken - ein gestaltungsorientierter Ansatz auf Basis von Text Analytics}, series = {Wissenstransfer in der Wirtschaftsinformatik Fachgespr{\"a}ch im Rahmen der MKWI 2018}, booktitle = {Wissenstransfer in der Wirtschaftsinformatik Fachgespr{\"a}ch im Rahmen der MKWI 2018}, editor = {Hofmann, Georg Rainer and Alm, Wolfgang}, publisher = {IMI-Verlag ; Hochschule Aschaffenburg, Information Management Institut}, address = {Aschaffenburg}, isbn = {9783981844207}, pages = {6 -- 15}, year = {2018}, abstract = {Angesichts des anhaltenden Wachstums wissenschaftlicher Ver{\"o}ffentlichungen werden Instrumente ben{\"o}tigt, um Literaturanalysen durch Digitalisierung produktiver zu gestalten. Dieser Beitrag stellt einen Ansatz vor, der bibliographische Daten aus der Literaturdatenbank EBSCO Discovery Service mithilfe von Text-Analytics-Methoden erschließt. Die L{\"o}sung basiert auf dem Textanalysesystem IBM Watson Explorer und eignet sich f{\"u}r explorative Literaturanalysen, um beispielsweise den Status quo emergierender Technologiefelder in der Literatur zu reflektieren. Die generierten Ergebnisse sind in den Kontext der zunehmenden Werkzeugunterst{\"u}tzung des Literaturrechercheprozesses einzuordnen und k{\"o}nnen f{\"u}r intra- sowie interinstitutionelle Wissenstransferprozesse in Forschungs- und Beratungskontexten genutzt werden.}, language = {de} } @inproceedings{NursinskiStolbergGangatharanCzarnecki2016, author = {Nursinski-Stolberg, Andr{\´e} and Gangatharan, Kiritharan and Czarnecki, Christian}, title = {Development of a subject-oriented reference process model for the telecommunications industry}, series = {GI Edition Proceedings Band 259 INFORMATIK 2016}, booktitle = {GI Edition Proceedings Band 259 INFORMATIK 2016}, editor = {Mayr, Heinrich C. and Pinzger, Martin}, publisher = {Gesellschaft f{\"u}r Informatik e.V.}, address = {Bonn}, isbn = {9783885796534}, issn = {1617-5468}, pages = {699 -- 712}, year = {2016}, abstract = {Generally the usage of reference models can be structured top-down or bottom-up. The practical need of agile change and flexible organizational implementation requires a consistent mapping to an operational level. In this context, well-established reference process models are typically structured top-down. The subject-oriented Business Process Management (sBPM) offers a modeling concept that is structured bottom-up and concentrates on the process actors on an operational level. This paper applies sBPM to the enhanced Telecom Operations Map (eTOM), a well-accepted reference process model in the telecommunications industry. The resulting design artifact is a concrete example for a combination of a bottom-up and top-down developed reference model. The results are evaluated and confirmed in practical context through the involvement of the industry body TMForum.}, language = {en} } @inproceedings{CzarneckiWinkelmannSpiliopoulou2012, author = {Czarnecki, Christian and Winkelmann, Axel and Spiliopoulou, Myra}, title = {Transformation in Telecommunication - Analyse und Clustering von Real-life Projekten}, series = {Multikonferenz Wirtschaftsinformatik 2012}, booktitle = {Multikonferenz Wirtschaftsinformatik 2012}, editor = {Mattfeld, Dirk Christian and Robra-Bissantz, Susanne}, publisher = {Gito}, address = {Berlin}, isbn = {9783942183635}, pages = {985 -- 998}, year = {2012}, abstract = {Die Ver{\"a}nderungen des Telekommunikationsmarktes haben in der Praxis zu einer Vielzahl von Transformationsprojekten gef{\"u}hrt. Was geh{\"o}rt aber zu einem "Transformationsprojekt", welche Prozesse und Systeme werden ver{\"a}ndert? Zur Beantwortung dieser Frage haben wir 184 Berichte zu Projekten analysiert, die als "Transformationsprojekte" bezeichnet waren. F{\"u}r die Analyse haben wir einen Kodierungsrahmen konzipiert und anhand dessen die Berichte mit einem hierarchischen Clustering-Verfahren in Themen gruppiert. Die Ergebnisse liefern Hinweise {\"u}ber die in der Praxis gesetzten Schwerpunkte und Priorit{\"a}ten. Sie k{\"o}nnen somit als Unterst{\"u}tzung f{\"u}r Unternehmen dienen, die ein Transformationsprojekt planen. Sie weisen zudem darauf hin, in welchen Bereichen eines Unternehmens Unterst{\"u}tzung durch wissenschaftlich erprobte Werkzeuge und Modelle n{\"o}tig ist.}, language = {de} } @inproceedings{CzarneckiWinkelmannSpiliopoulou2011, author = {Czarnecki, Christian and Winkelmann, Axel and Spiliopoulou, Myra}, title = {Making business systems in the telecommunication industry more customer-oriented}, series = {Information Systems Development : Business Systems and Services: Modeling and Development}, booktitle = {Information Systems Development : Business Systems and Services: Modeling and Development}, editor = {Pokorny, Jaroslav and Repa, Vaclav and Richta, Karel and Wojtkowski, Wita and Linger, Henry and Barry, Chris and Lang, Michael}, publisher = {Springer}, address = {New York}, isbn = {978-1-4419-9645-9 (Print)}, doi = {10.1007/978-1-4419-9790-6_14}, pages = {169 -- 180}, year = {2011}, abstract = {Market changes have forced telecommunication companies to transform their business. Increased competition, short innovation cycles, changed usage patterns, increased customer expectations and cost reduction are the main drivers. Our objective is to analyze to what extend transformation projects have improved the orientation towards the end-customers. Therefore, we selected 38 real-life case studies that are dealing with customer orientation. Our analysis is based on a telecommunication-specific framework that aligns strategy, business processes and information systems. The result of our analysis shows the following: transformation projects that aim to improve the customer orientation are combined with clear goals on costs and revenue of the enterprise. These projects are usually directly linked to the customer touch points, but also to the development and provisioning of products. Furthermore, the analysis shows that customer orientation is not the sole trigger for transformation. There is no one-fits-all solution; rather, improved customer orientation needs aligned changes of business processes as well as information systems related to different parts of the company.}, language = {en} } @inproceedings{Czarnecki2011, author = {Czarnecki, Christian}, title = {Gestaltung von Customer Relationship Management {\"u}ber die Grenzen von Telekommunikationsunternehmen hinweg}, series = {Tagungsband zum Doctoral Consortium der WI 2009}, booktitle = {Tagungsband zum Doctoral Consortium der WI 2009}, editor = {Eymann, Torsten}, publisher = {Universit{\"a}t Bayreuth Lehrstuhl f{\"u}r Wirtschaftsinformatik}, address = {Bayreuth}, issn = {1864-9300}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:703-opus-5462}, pages = {11 -- 23}, year = {2011}, abstract = {Durch die Fragmentierung von Wertsch{\"o}pfungsketten ergeben sich neue Herausforderungen f{\"u}r das Management von Kundenbeziehungen. Die Dissertation untersucht die daraus resultierenden Anforderungen an eine {\"u}bergreifende Integration von Customer Relationship Management in der Telekommunikationsindustrie. Ziel ist es, durch Anwendung von Methoden eines Enterprise Architecture Framework eine {\"u}bergreifend L{\"o}sung zu gestalten. Grundlegende Pr{\"a}misse dabei ist, dass die {\"u}bergreifende Gestaltung eines Customer Relationship Management f{\"u}r alle an der Wertsch{\"o}pfung beteiligten Unternehmen vorteilhaft ist.}, language = {de} } @inproceedings{CzarneckiHeuserSpiliopoulou2009, author = {Czarnecki, Christian and Heuser, Marcus and Spiliopoulou, Myra}, title = {How does the implementation of a next generation network influence a telecommunication company?}, series = {European and Mediterranean Conference on Information Systems}, booktitle = {European and Mediterranean Conference on Information Systems}, editor = {Irani, Zahir}, publisher = {Brunel University}, address = {London}, isbn = {9781902316697}, pages = {1 -- 11}, year = {2009}, abstract = {As the potential of a Next Generation Network (NGN) is recognized, telecommunication companies consider switching to it. Although the implementation of an NGN seems to be merely a modification of the network infrastructure, it may trigger or require changes in the whole company and even influence the company strategy. To capture the effects of NGN we propose a framework based on concepts of business engineering and technical recommendations for the introduction of NGN technology. The specific design of solutions for the layers "Strategy", "Processes" and "Information Systems" as well as their interdependencies are an essential characteristic of the developed framework. We have per-formed a case study on NGN implementation and observed that all layers captured by our framework are influenced by the introduction of an NGN.}, language = {en} } @inproceedings{EndressBragard2017, author = {Endress, Tim and Bragard, Michael}, title = {Recording of efficiency-maps of low-power electric drive systems using a flexible matlab-based test bench}, series = {2017 IEEE 58th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON)}, booktitle = {2017 IEEE 58th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON)}, publisher = {IEEE}, address = {New York}, isbn = {978-1-5386-3846-0}, doi = {10.1109/RTUCON.2017.8124775}, pages = {5 Seiten}, year = {2017}, abstract = {This paper introduces a hardware setup to measure efficiency maps of low-power electric motors and their associated inverters. Here, the power of the device under test (DUT) ranges from some Watts to a few hundred Watts. The torque and speed of the DUT are measured independent of voltage and current in multiple load points. A Matlab-based software approach in combination with an open Texas-Instruments (TI) hardware setup ensures flexibility. Exemplarily, the efficiency field of a Permanent Magnet Synchronous Machine (PMSM) is measured to proof the concept. Brushless-DC (BLDC) motors can be tested as well. The nomenclature in this paper is based on the new European standard DIN EN 50598. Special attention is paid to the calculation of the measurement error.}, language = {en} } @inproceedings{CordesGligorevicBlicharski2019, author = {Cordes, Sven and Gligorevic, Snjezana and Blicharski, Peter}, title = {Analysis of sine precision influence on DOA estimation using the MUSIC algorithm}, series = {2019 20th International Radar Symposium (IRS)}, booktitle = {2019 20th International Radar Symposium (IRS)}, isbn = {978-3-7369-9860-5}, doi = {10.23919/IRS.2019.8768162}, pages = {1 -- 10}, year = {2019}, language = {en} } @inproceedings{GaldiHartungDugelay2019, author = {Galdi, Chiara and Hartung, Frank and Dugelay, Jean-Luc}, title = {Socrates: A database of realistic data for source camera recognition on smartphones}, series = {Proceedings of the 8th International Conference on Pattern Recognition Applications and Methods - Volume 1: ICPRAM}, booktitle = {Proceedings of the 8th International Conference on Pattern Recognition Applications and Methods - Volume 1: ICPRAM}, isbn = {978-989-758-351-3}, doi = {10.5220/0007403706480655}, pages = {648 -- 655}, year = {2019}, language = {en} } @inproceedings{SchifferBragard2019, author = {Schiffer, Fabian and Bragard, Michael}, title = {Cascaded LQ and Field-Oriented Control of a Mobile Inverse Pendulum (Segway) with Permanent Magnet Synchronous Machines}, series = {2019 20th International Conference on Research and Education in Mechatronics (REM)}, booktitle = {2019 20th International Conference on Research and Education in Mechatronics (REM)}, isbn = {978-1-5386-9257-8}, doi = {10.1109/REM.2019.8744101}, pages = {1 -- 8}, year = {2019}, language = {en} } @inproceedings{BragardSubeSchneideretal.2019, author = {Bragard, Michael and Sube, Maike and Schneider, Maike and Jungemann, Christoph}, title = {Introducing a Cross-University Bachelor's Programme with Orientation Semester - Enabling a Permeable Academic Education System}, series = {2019 20th International Conference on Research and Education in Mechatronics (REM)}, booktitle = {2019 20th International Conference on Research and Education in Mechatronics (REM)}, isbn = {978-1-5386-9257-8}, doi = {10.1109/REM.2019.8744132}, pages = {1 -- 6}, year = {2019}, language = {en} } @inproceedings{WiegnerVolkerMainzetal.2022, author = {Wiegner, Jonas and Volker, Hanno and Mainz, Fabian and Backes, Andreas and L{\"o}ken, Michael and H{\"u}ning, Felix}, title = {Wiegand-effect-powered wireless IoT sensor node}, series = {ITG-Fb. 303: Sensoren und Messsysteme}, booktitle = {ITG-Fb. 303: Sensoren und Messsysteme}, publisher = {VDE Verlag GmbH}, address = {Berlin}, isbn = {978-3-8007-5835-7}, pages = {255 -- 260}, year = {2022}, abstract = {In this article we describe an Internet-of-Things sensing device with a wireless interface which is powered by the oftenoverlooked harvesting method of the Wiegand effect. The sensor can determine position, temperature or other resistively measurable quantities and can transmit the data via an ultra-low power ultra-wideband (UWB) data transmitter. With this approach we can energy-self-sufficiently acquire, process, and wirelessly transmit data in a pulsed operation. A proof-of-concept system was built up to prove the feasibility of the approach. The energy consumption of the system is analyzed and traced back in detail to the individual components, compared to the generated energy and processed to identify further optimization options. Based on the proof-of-concept, an application demonstrator was developed. Finally, we point out possible use cases.}, language = {en} } @inproceedings{LorenzAltherrPelz2020, author = {Lorenz, Imke-Sophie and Altherr, Lena and Pelz, Peter F.}, title = {Assessing and Optimizing the Resilience of Water Distribution Systems Using Graph-Theoretical Metrics}, series = {Operations Research Proceedings 2019}, booktitle = {Operations Research Proceedings 2019}, editor = {Neufeld, Janis S. and Buscher, Udo and Lasch, Rainer and M{\"o}st, Dominik and Sch{\"o}nberger, J{\"o}rn}, publisher = {Springer}, address = {Cham}, isbn = {978-3-030-48439-2}, doi = {10.1007/978-3-030-48439-2_63}, pages = {521 -- 527}, year = {2020}, abstract = {Water distribution systems are an essential supply infrastructure for cities. Given that climatic and demographic influences will pose further challenges for these infrastructures in the future, the resilience of water supply systems, i.e. their ability to withstand and recover from disruptions, has recently become a subject of research. To assess the resilience of a WDS, different graph-theoretical approaches exist. Next to general metrics characterizing the network topology, also hydraulic and technical restrictions have to be taken into account. In this work, the resilience of an exemplary water distribution network of a major German city is assessed, and a Mixed-Integer Program is presented which allows to assess the impact of capacity adaptations on its resilience.}, language = {en} } @inproceedings{LeiseSimonAltherr2020, author = {Leise, Philipp and Simon, Nicolai and Altherr, Lena}, title = {Comparison of Piecewise Linearization Techniques to Model Electric Motor Efficiency Maps: A Computational Study}, series = {Operations Research Proceedings 2019}, booktitle = {Operations Research Proceedings 2019}, publisher = {Springer}, address = {Cham}, isbn = {978-3-030-48439-2}, doi = {10.1007/978-3-030-48439-2_55}, pages = {457 -- 463}, year = {2020}, abstract = {To maximize the travel distances of battery electric vehicles such as cars or buses for a given amount of stored energy, their powertrains are optimized energetically. One key part within optimization models for electric powertrains is the efficiency map of the electric motor. The underlying function is usually highly nonlinear and nonconvex and leads to major challenges within a global optimization process. To enable faster solution times, one possibility is the usage of piecewise linearization techniques to approximate the nonlinear efficiency map with linear constraints. Therefore, we evaluate the influence of different piecewise linearization modeling techniques on the overall solution process and compare the solution time and accuracy for methods with and without explicitly used binary variables.}, language = {en} } @inproceedings{MuellerSchmittLeiseetal.2021, author = {M{\"u}ller, Tim M. and Schmitt, Andreas and Leise, Philipp and Meck, Tobias and Altherr, Lena and Pelz, Peter F. and Pfetsch, Marc E.}, title = {Validation of an optimized resilient water supply system}, series = {Uncertainty in Mechanical Engineering}, booktitle = {Uncertainty in Mechanical Engineering}, publisher = {Springer}, address = {Cham}, isbn = {978-3-030-77255-0}, doi = {10.1007/978-3-030-77256-7_7}, pages = {70 -- 80}, year = {2021}, abstract = {Component failures within water supply systems can lead to significant performance losses. One way to address these losses is the explicit anticipation of failures within the design process. We consider a water supply system for high-rise buildings, where pump failures are the most likely failure scenarios. We explicitly consider these failures within an early design stage which leads to a more resilient system, i.e., a system which is able to operate under a predefined number of arbitrary pump failures. We use a mathematical optimization approach to compute such a resilient design. This is based on a multi-stage model for topology optimization, which can be described by a system of nonlinear inequalities and integrality constraints. Such a model has to be both computationally tractable and to represent the real-world system accurately. We therefore validate the algorithmic solutions using experiments on a scaled test rig for high-rise buildings. The test rig allows for an arbitrary connection of pumps to reproduce scaled versions of booster station designs for high-rise buildings. We experimentally verify the applicability of the presented optimization model and that the proposed resilience properties are also fulfilled in real systems.}, language = {en} } @inproceedings{HueningWacheMagiera2021, author = {H{\"u}ning, Felix and Wache, Franz-Josef and Magiera, David}, title = {Redundant bus systems using dual-mode radio}, series = {Proceedings of Sixth International Congress on Information and Communication Technology}, booktitle = {Proceedings of Sixth International Congress on Information and Communication Technology}, publisher = {Springer}, address = {Singapore}, isbn = {978-981-16-2379-0}, doi = {10.1007/978-981-16-2380-6_73}, pages = {835 -- 842}, year = {2021}, abstract = {Communication via serial bus systems, like CAN, plays an important role for all kinds of embedded electronic and mechatronic systems. To cope up with the requirements for functional safety of safety-critical applications, there is a need to enhance the safety features of the communication systems. One measure to achieve a more robust communication is to add redundant data transmission path to the applications. In general, the communication of real-time embedded systems like automotive applications is tethered, and the redundant data transmission lines are also tethered, increasing the size of the wiring harness and the weight of the system. A radio link is preferred as a redundant transmission line as it uses a complementary transmission medium compared to the wired solution and in addition reduces wiring harness size and weight. Standard wireless links like Wi-Fi or Bluetooth cannot meet the requirements for real-time capability with regard to bus communication. Using the new dual-mode radio enables a redundant transmission line meeting all requirements with regard to real-time capability, robustness and transparency for the data bus. In addition, it provides a complementary transmission medium with regard to commonly used tethered links. A CAN bus system is used to demonstrate the redundant data transfer via tethered and wireless CAN.}, language = {en} } @inproceedings{MeckMuellerAltherretal.2020, author = {Meck, Marvin M. and M{\"u}ller, Tim M. and Altherr, Lena and Pelz, Peter F.}, title = {Improving an industrial cooling system using MINLP, considering capital and operating costs}, series = {Operations Research Proceedings 2019}, booktitle = {Operations Research Proceedings 2019}, publisher = {Springer}, address = {Cham}, isbn = {978-3-030-48438-5 (Print)}, doi = {10.1007/978-3-030-48439-2_61}, pages = {505 -- 512}, year = {2020}, abstract = {The chemical industry is one of the most important industrial sectors in Germany in terms of manufacturing revenue. While thermodynamic boundary conditions often restrict the scope for reducing the energy consumption of core processes, secondary processes such as cooling offer scope for energy optimisation. In this contribution, we therefore model and optimise an existing cooling system. The technical boundary conditions of the model are provided by the operators, the German chemical company BASF SE. In order to systematically evaluate different degrees of freedom in topology and operation, we formulate and solve a Mixed-Integer Nonlinear Program (MINLP), and compare our optimisation results with the existing system.}, language = {en} } @inproceedings{MuellerAltherrLeiseetal.2020, author = {M{\"u}ller, Tim M. and Altherr, Lena and Leise, Philipp and Pelz, Peter F.}, title = {Optimization of pumping systems for buildings: Experimental validation of different degrees of model detail on a modular test rig}, series = {Operations Research Proceedings 2019}, booktitle = {Operations Research Proceedings 2019}, publisher = {Springer}, address = {Cham}, isbn = {978-3-030-48438-5}, doi = {10.1007/978-3-030-48439-2_58}, pages = {481 -- 488}, year = {2020}, abstract = {Successful optimization requires an appropriate model of the system under consideration. When selecting a suitable level of detail, one has to consider solution quality as well as the computational and implementation effort. In this paper, we present a MINLP for a pumping system for the drinking water supply of high-rise buildings. We investigate the influence of the granularity of the underlying physical models on the solution quality. Therefore, we model the system with a varying level of detail regarding the friction losses, and conduct an experimental validation of our model on a modular test rig. Furthermore, we investigate the computational effort and show that it can be reduced by the integration of domain-specific knowledge.}, language = {en} } @inproceedings{EssingholtMeyerKuhnetal.2018, author = {Essingholt, Felix and Meyer, Frederic and Kuhn, Peter and Schmidt, Philip and Benkner, Thorsten and Grabmaier, Anton}, title = {Non-invasive heart beat measurement using microwave resonators}, series = {Proceedings, Vol. 2, Eurosensors 2018 Conference, Graz, Austria, 9-12 September 2018}, booktitle = {Proceedings, Vol. 2, Eurosensors 2018 Conference, Graz, Austria, 9-12 September 2018}, publisher = {MDPI}, address = {Basel}, issn = {2504-3900}, doi = {10.3390/proceedings2131002}, pages = {1002}, year = {2018}, language = {en} } @inproceedings{HoegenDonckerRuetters2020, author = {Hoegen, Anne von and Doncker, Rik W. De and R{\"u}tters, Ren{\´e}}, title = {Teaching Digital Control of Operational Amplifier Processes with a LabVIEW Interface and Embedded Hardware}, series = {2020 23rd International Conference on Electrical Machines and Systems (ICEMS)}, booktitle = {2020 23rd International Conference on Electrical Machines and Systems (ICEMS)}, publisher = {IEEE}, address = {New York, NY}, doi = {10.23919/ICEMS50442.2020.9290928}, pages = {1117 -- 1122}, year = {2020}, abstract = {Control engineering theory is hard to grasp for undergraduates during the first semesters, as it deals with the dynamical behavior of systems also in combination with control strategies on an abstract level. Therefore, operational amplifier (OpAmp) processes are reasonable and very effective systems to connect mathematical description with actual system's behavior. In this paper, we present an experiment for a laboratory session in which an embedded system, driven by a LabVIEW human machine interface (HMI) via USB, controls the analog circuits.With this setup we want to show the possibility of firstly, analyzing a first order process and secondly, designing a P-and PI-controller. Thereby, the theory of control engineering is always applied to the empirical results in order to break down the abstract level for the students.}, language = {en} } @inproceedings{SchubaHoefkenLinzbach2022, author = {Schuba, Marko and H{\"o}fken, Hans-Wilhelm and Linzbach, Sophie}, title = {An ICS Honeynet for Detecting and Analyzing Cyberattacks in Industrial Plants}, series = {2021 International Conference on Electrical, Computer and Energy Technologies (ICECET)}, booktitle = {2021 International Conference on Electrical, Computer and Energy Technologies (ICECET)}, publisher = {IEEE}, isbn = {978-1-6654-4231-2}, doi = {10.1109/ICECET52533.2021.9698746}, pages = {6 Seiten}, year = {2022}, abstract = {Cybersecurity of Industrial Control Systems (ICS) is an important issue, as ICS incidents may have a direct impact on safety of people or the environment. At the same time the awareness and knowledge about cybersecurity, particularly in the context of ICS, is alarmingly low. Industrial honeypots offer a cheap and easy to implement way to raise cybersecurity awareness and to educate ICS staff about typical attack patterns. When integrated in a productive network, industrial honeypots may not only reveal attackers early but may also distract them from the actual important systems of the network. Implementing multiple honeypots as a honeynet, the systems can be used to emulate or simulate a whole Industrial Control System. This paper describes a network of honeypots emulating HTTP, SNMP, S7communication and the Modbus protocol using Conpot, IMUNES and SNAP7. The nodes mimic SIMATIC S7 programmable logic controllers (PLCs) which are widely used across the globe. The deployed honeypots' features will be compared with the features of real SIMATIC S7 PLCs. Furthermore, the honeynet has been made publicly available for ten days and occurring cyberattacks have been analyzed}, language = {en} } @inproceedings{ChristianMontagSchubaetal.2018, author = {Christian, Esser and Montag, Tim and Schuba, Marko and Allhof, Manuel}, title = {Future critical infrastructure and security - cyberattacks on charging stations}, series = {31st International Electric Vehicle Symposium \& Exhibition and International Electric Vehicle Technology Conference (EVS31 \& EVTeC 2018)}, booktitle = {31st International Electric Vehicle Symposium \& Exhibition and International Electric Vehicle Technology Conference (EVS31 \& EVTeC 2018)}, publisher = {Society of Automotive Engineers of Japan (JSAE)}, address = {Tokyo}, isbn = {978-1-5108-9157-9}, pages = {665 -- 671}, year = {2018}, language = {en} } @inproceedings{NeugebauerBrutschyMeyeretal.2014, author = {Neugebauer, Georg and Brutschy, Lucas and Meyer, Ulrike and Wetzel, Susanne}, title = {Privacy-preserving multi-party reconciliation secure in the malicious model}, series = {DPM 2013, SETOP 2013: Data Privacy Management and Autonomous Spontaneous Security}, booktitle = {DPM 2013, SETOP 2013: Data Privacy Management and Autonomous Spontaneous Security}, editor = {Garcia-Alfaro, Joaquin and Lioudakis, Georgios and Cuppens-Boulahia, Nora and Foley, Simon and Fitzgerald, William M.}, publisher = {Springer}, address = {Berlin}, isbn = {978-3-642-54567-2 (Print)}, doi = {10.1007/978-3-642-54568-9_12}, pages = {178 -- 193}, year = {2014}, abstract = {The problem of fair and privacy-preserving ordered set reconciliation arises in a variety of applications like auctions, e-voting, and appointment reconciliation. While several multi-party protocols have been proposed that solve this problem in the semi-honest model, there are no multi-party protocols that are secure in the malicious model so far. In this paper, we close this gap. Our newly proposed protocols are shown to be secure in the malicious model based on a variety of novel non-interactive zero-knowledge-proofs. We describe the implementation of our protocols and evaluate their performance in comparison to protocols solving the problem in the semi-honest case.}, language = {en} } @inproceedings{NethSchubaBrodkorbetal.2023, author = {Neth, Jannik and Schuba, Marko and Brodkorb, Karsten and Neugebauer, Georg and H{\"o}ner, Tim and Hack, Sacha}, title = {Digital forensics triage app for android}, series = {ARES '23: Proceedings of the 18th International Conference on Availability, Reliability and Security}, booktitle = {ARES '23: Proceedings of the 18th International Conference on Availability, Reliability and Security}, publisher = {ACM}, isbn = {9798400707728}, doi = {10.1145/3600160.3605017}, pages = {6 Seiten}, year = {2023}, abstract = {Digital forensics of smartphones is of utmost importance in many criminal cases. As modern smartphones store chats, photos, videos etc. that can be relevant for investigations and as they can have storage capacities of hundreds of gigabytes, they are a primary target for forensic investigators. However, it is exactly this large amount of data that is causing problems: extracting and examining the data from multiple phones seized in the context of a case is taking more and more time. This bears the risk of wasting a lot of time with irrelevant phones while there is not enough time left to analyze a phone which is worth examination. Forensic triage can help in this case: Such a triage is a preselection step based on a subset of data and is performed before fully extracting all the data from the smartphone. Triage can accelerate subsequent investigations and is especially useful in cases where time is essential. The aim of this paper is to determine which and how much data from an Android smartphone can be made directly accessible to the forensic investigator - without tedious investigations. For this purpose, an app has been developed that can be used with extremely limited storage of data in the handset and which outputs the extracted data immediately to the forensic workstation in a human- and machine-readable format.}, language = {en} }