@inproceedings{SchwankeHoefkenSchuba2017, author = {Schwanke, Peter and H{\"o}fken, Hans-Wilhelm and Schuba, Marko}, title = {Security Analysis of the ADS Protocol of a Beckhoff CX2020 PLC}, pages = {1 -- 5}, year = {2017}, abstract = {ICSs (Industrial Control Systems) and its subset SCADA systems (Supervisory Control and Data Acquisition) are getting exposed to a constant stream of new threats. The increasing importance of IT security in ICS requires viable methods to assess the security of ICS, its individual components, and its protocols. This paper presents a security analysis with focus on the communication protocols of a single PLC (Programmable Logic Controller). The PLC, a Beckhoff CX2020, is examined and new vulnerabilities of the system are revealed. Based on these findings recommendations are made to improve security of the Beckhoff system and its protocols.}, language = {en} } @inproceedings{GranatHoefkenSchuba2017, author = {Granat, Andreas and H{\"o}fken, Hans-Wilhelm and Schuba, Marko}, title = {Intrusion Detection of the ICS Protocol EtherCAT}, pages = {1 -- 5}, year = {2017}, abstract = {Control mechanisms like Industrial Controls Systems (ICS) and its subgroup SCADA (Supervisory Control and Data Acquisition) are a prerequisite to automate industrial processes. While protection of ICS on process management level is relatively straightforward - well known office IT security mechanisms can be used - protection on field bus level is harder to achieve as there are real-time and production requirements like 24x7 to consider. One option to improve security on field bus level is to introduce controls that help to detect and to react on attacks. This paper introduces an initial set of intrusion detection mechanisms for the field bus protocol EtherCAT. To this end existing Ethernet attack vectors including packet injection and man-in-the-middle attacks are tested in an EtherCAT environment, where they could interrupt the EtherCAT network and may even cause physical damage. Based on the signatures of such attacks, a preprocessor and new rule options are defined for the open source intrusion detection system Snort demonstrating the general feasibility of intrusion detection on field bus level.}, language = {en} } @inproceedings{BitzKlompLadd2009, author = {Bitz, Andreas and Klomp, D.W. and Ladd, M.E.}, title = {Experimental and numerical determination of SAR and temperature distribution of a human endorectal coil for MR imaging of the prostate at 7T (903.)}, series = {16th annual ISMRM scientific meeting and exhibition 2008 : Toronto, Ontario, Canada, 3 - 9 May 2008}, booktitle = {16th annual ISMRM scientific meeting and exhibition 2008 : Toronto, Ontario, Canada, 3 - 9 May 2008}, publisher = {Curran}, address = {Red Hook, NY}, isbn = {978-1-61567-196-0}, year = {2009}, language = {en} } @inproceedings{BitzElOuardiStreckertetal.2005, author = {Bitz, Andreas and El Ouardi, A. and Streckert, J. and Hansen, V.}, title = {Efficient calculation of human exposure in front of base station antennas by a combination of the FDTD and Hybrid(2)-method}, series = {Proceedings of the 16th International Zurich Symposium on Electromagnetic Compatibility, Topical Meeting on Biomedical EMC, Zurich, Switzerland, February 2005}, booktitle = {Proceedings of the 16th International Zurich Symposium on Electromagnetic Compatibility, Topical Meeting on Biomedical EMC, Zurich, Switzerland, February 2005}, publisher = {ETH Zentrum}, address = {Z{\"u}rich}, isbn = {3-9521199-9-7}, pages = {115 -- 118}, year = {2005}, language = {en} } @inproceedings{BitzAlaydrusStreckertetal.2002, author = {Bitz, Andreas and Alaydrus, M. and Streckert, J. and Hansen, V.}, title = {Combination of the hybrid/sup [2]/-method and the FDTD-method for solution of boundary value problems with electrically large and high-resolution bodies}, series = {IEEE Antennas and Propagation Society International Symposium (IEEE Cat. No.02CH37313) 2002 : San Antonio, TX, USA, 16-21 June}, booktitle = {IEEE Antennas and Propagation Society International Symposium (IEEE Cat. No.02CH37313) 2002 : San Antonio, TX, USA, 16-21 June}, publisher = {IEEE}, address = {Piscataway, NJ}, isbn = {0-7803-7330-8}, doi = {10.1109/APS.2002.1018209}, pages = {278 -- 281}, year = {2002}, language = {en} } @inproceedings{BitzAlaydrusStreckertetal.2002, author = {Bitz, Andreas and Alaydrus, M. and Streckert, J. and Hansen, V.W.}, title = {Absorption rates inside human body due to radiated electro-magnetic fields of multi-band base station antennas. Boundary value problems with electrically large and high-resolution bodies}, series = {24th BEMS Annual Meeting, Quebec City, Quebec, Canada, 23 - 27 June 2002}, booktitle = {24th BEMS Annual Meeting, Quebec City, Quebec, Canada, 23 - 27 June 2002}, publisher = {Bioelectromagnetics Society}, address = {Frederick, MD}, pages = {40 -- 41}, year = {2002}, language = {en} } @inproceedings{BitzAlaydrusStreckertetal.2001, author = {Bitz, Andreas and Alaydrus, M. and Streckert, J. and Hansen, V.W.}, title = {Base station antennas embedded in complex environments: rf exposure in controlled areas}, series = {23rd BEMS Annual Meeting, St. Paul, Minnesota, USA, 49-50, June 2001}, booktitle = {23rd BEMS Annual Meeting, St. Paul, Minnesota, USA, 49-50, June 2001}, publisher = {Bioelectromagnetics Society}, address = {Frederick, MD}, pages = {49 -- 50}, year = {2001}, language = {en} } @inproceedings{BitzStreckertHansenetal.2001, author = {Bitz, Andreas and Streckert, J. and Hansen, V.W. and Stogbauer, F.}, title = {Shielded RF-exposure system with an integrated LF-measuring system for in vitro experiments with cell-layers}, series = {Proceedings of the Ebea 2001 : 5th International Congress of the European Bioelectromagnetics Association (Ebea) ; 6-8 September 2001, Marina Congress Center, Helsinki, Finland}, booktitle = {Proceedings of the Ebea 2001 : 5th International Congress of the European Bioelectromagnetics Association (Ebea) ; 6-8 September 2001, Marina Congress Center, Helsinki, Finland}, editor = {Hietanen, Maila and Jokela, Kari and Juutilainen, Jukka and Työterveyslaitos,}, publisher = {Finnish Institute of Occupational Health}, address = {Helsinki}, isbn = {9789518024401}, pages = {67 -- 68}, year = {2001}, language = {en} } @inproceedings{BitzStreckertHansenetal.2000, author = {Bitz, Andreas and Streckert, J.R. and Hansen, V.W. and Lerchl, A.}, title = {Freely moving or restrained animals in bioelec-tromagnetic experiments - pros and cons}, series = {AP 2000 : Millennium Conference on Antennas \& Propagation, Davos, Switzerland, 9 - 14 April 2000}, booktitle = {AP 2000 : Millennium Conference on Antennas \& Propagation, Davos, Switzerland, 9 - 14 April 2000}, number = {Band 1}, editor = {Danesy, Dorothea}, publisher = {ESA Publications Division, ESTEC}, address = {Noordwijk}, pages = {489}, year = {2000}, language = {en} } @inproceedings{BitzKobusScheenenetal.2013, author = {Bitz, Andreas and Kobus, Thiele and Scheenen, Tom W. J. and Ladd, Mark E.}, title = {RF Safety of the Combination of a 31P Tx/Rx Endorectal Coil \& a 1H Tx/Rx Body Array for 31P MRSI of the Prostate at 7T (311.)}, series = {20th Annual ISMRM scientific meeting and exhibition 2012 : Melbourne, Australia, 5 - 11 May 2012}, booktitle = {20th Annual ISMRM scientific meeting and exhibition 2012 : Melbourne, Australia, 5 - 11 May 2012}, number = {Volume 1}, publisher = {Curran}, address = {Red Hook, NY}, isbn = {978-1-62276-943-8}, issn = {1545-4428}, pages = {311}, year = {2013}, language = {en} } @inproceedings{BitzKraffOrzadaetal.2012, author = {Bitz, Andreas and Kraff, O. and Orzada, S. and Maderwald, S. and Brote, I. and Johst, S. and Ladd, E.}, title = {Assessment of RF Safety of Transmit Coils at 7 Tesla by Experimental and Numerical Procedures (490.)}, series = {19th annual ISMRM scientific meeting and exhibition 2011 : Montreal, Quebec, Canada, 7 - 13 May 2011}, booktitle = {19th annual ISMRM scientific meeting and exhibition 2011 : Montreal, Quebec, Canada, 7 - 13 May 2011}, number = {Volume 1}, publisher = {Curran}, address = {Red Hook, NY}, isbn = {978-1-61839-284-8}, pages = {475}, year = {2012}, language = {en} } @inproceedings{BitzKraffOrzadaetal.2010, author = {Bitz, Andreas and Kraff, O. and Orzada, S. and Maderwald, S. and Brote, I. and Ladd, M.}, title = {Experimental and Numerical Assessment of RF Safety of Transmit Coils at 7 Tesla}, series = {ISMRM workshop on MR safety 2010 : RF heating of the human in MRI : workshop series. The Washington County Historic Courthouse, Stillwater, Minnesota, USA, 15 - 17 October 2010}, booktitle = {ISMRM workshop on MR safety 2010 : RF heating of the human in MRI : workshop series. The Washington County Historic Courthouse, Stillwater, Minnesota, USA, 15 - 17 October 2010}, isbn = {978-1-62276-088-6}, pages = {195}, year = {2010}, language = {en} } @inproceedings{SchollBartellaMoluluoetal.2019, author = {Scholl, Ingrid and Bartella, Alex and Moluluo, Cem and Ertural, Berat and Laing, Frederic and Suder, Sebastian}, title = {MedicVR : Acceleration and Enhancement Techniques for Direct Volume Rendering in Virtual Reality}, series = {Bildverarbeitung f{\"u}r die Medizin 2019 : Algorithmen - Systeme - Anwendungen}, booktitle = {Bildverarbeitung f{\"u}r die Medizin 2019 : Algorithmen - Systeme - Anwendungen}, publisher = {Springer Vieweg}, address = {Wiesbaden}, isbn = {978-3-658-25326-4}, doi = {10.1007/978-3-658-25326-4_32}, pages = {152 -- 157}, year = {2019}, language = {en} } @inproceedings{SerrorHenzeHacketal.2018, author = {Serror, Martin and Henze, Martin and Hack, Sacha and Schuba, Marko and Wehrle, Klaus}, title = {Towards in-network security for smart homes}, series = {13th International Conference on Availability, Reliability and Security, ARES 2018; Hamburg; Germany; 27 August 2018 through 30 August 2018}, booktitle = {13th International Conference on Availability, Reliability and Security, ARES 2018; Hamburg; Germany; 27 August 2018 through 30 August 2018}, isbn = {978-145036448-5}, doi = {10.1145/3230833.3232802}, pages = {Article numer 3232802}, year = {2018}, language = {en} } @inproceedings{DinghoferHartung2020, author = {Dinghofer, Kai and Hartung, Frank}, title = {Analysis of Criteria for the Selection of Machine Learning Frameworks}, series = {2020 International Conference on Computing, Networking and Communications (ICNC)}, booktitle = {2020 International Conference on Computing, Networking and Communications (ICNC)}, publisher = {IEEE}, address = {New York, NY}, doi = {10.1109/ICNC47757.2020.9049650}, pages = {373 -- 377}, year = {2020}, abstract = {With the many achievements of Machine Learning in the past years, it is likely that the sub-area of Deep Learning will continue to deliver major technological breakthroughs [1]. In order to achieve best results, it is important to know the various different Deep Learning frameworks and their respective properties. This paper provides a comparative overview of some of the most popular frameworks. First, the comparison methods and criteria are introduced and described with a focus on computer vision applications: Features and Uses are examined by evaluating papers and articles, Adoption and Popularity is determined by analyzing a data science study. Then, the frameworks TensorFlow, Keras, PyTorch and Caffe are compared based on the previously described criteria to highlight properties and differences. Advantages and disadvantages are compared, enabling researchers and developers to choose a framework according to their specific needs.}, language = {en} } @inproceedings{Huening2021, author = {H{\"u}ning, Felix}, title = {Sustainable changes beyond covid-19 for a second semester physics course for electrical engineering students}, series = {Blended Learning in Engineering Education: challenging, enlightening - and lasting?}, booktitle = {Blended Learning in Engineering Education: challenging, enlightening - and lasting?}, isbn = {978-2-87352-023-6}, pages = {1424 -- 1428}, year = {2021}, abstract = {The course Physics for Electrical Engineering is part of the curriculum of the bachelor program Electrical Engineering at University of Applied Science Aachen. Before covid-19 the course was conducted in a rather traditional way with all parts (lecture, exercise and lab) face-to-face. This teaching approach changed fundamentally within a week when the covid-19 limitations forced all courses to distance learning. All parts of the course were transformed to pure distance learning including synchronous and asynchronous parts for the lecture, live online-sessions for the exercises and self-paced labs at home. Using these methods, the course was able to impart the required knowledge and competencies. Taking the teacher's observations of the student's learning behaviour and engagement, the formal and informal feedback of the students and the results of the exams into account, the new methods are evaluated with respect to effectiveness, sustainability and suitability for competence transfer. Based on this analysis strong and weak points of the concept and countermeasures to solve the weak points were identified. The analysis further leads to a sustainable teaching approach combining synchronous and asynchronous parts with self-paced learning times that can be used in a very flexible manner for different learning scenarios, pure online, hybrid (mixture of online and presence times) and pure presence teaching.}, language = {en} } @inproceedings{LeiseBreuerAltherretal.2020, author = {Leise, Philipp and Breuer, Tim and Altherr, Lena and Pelz, Peter F.}, title = {Development, validation and assessment of a resilient pumping system}, series = {Proceedings of the Joint International Resilience Conference, JIRC2020}, booktitle = {Proceedings of the Joint International Resilience Conference, JIRC2020}, isbn = {978-90-365-5095-6}, pages = {97 -- 100}, year = {2020}, abstract = {The development of resilient technical systems is a challenging task, as the system should adapt automatically to unknown disturbances and component failures. To evaluate different approaches for deriving resilient technical system designs, we developed a modular test rig that is based on a pumping system. On the basis of this example system, we present metrics to quantify resilience and an algorithmic approach to improve resilience. This approach enables the pumping system to automatically react on unknown disturbances and to reduce the impact of component failures. In this case, the system is able to automatically adapt its topology by activating additional valves. This enables the system to still reach a minimum performance, even in case of failures. Furthermore, timedependent disturbances are evaluated continuously, deviations from the original state are automatically detected and anticipated in the future. This allows to reduce the impact of future disturbances and leads to a more resilient system behaviour.}, language = {en} } @inproceedings{LorenzAltherrPelz2019, author = {Lorenz, Imke-Sophie B. and Altherr, Lena and Pelz, Peter F.}, title = {Graph-theoretic resilience analysis of a water distribution system's topology}, series = {World Congress on Resilience, Reliability and Asset Management 2019}, booktitle = {World Congress on Resilience, Reliability and Asset Management 2019}, pages = {106 -- 109}, year = {2019}, abstract = {Water suppliers are faced with the great challenge of achieving high-quality and, at the same time, low-cost water supply. In practice, the focus is set on the most beneficial maintenance measures and/or capacity adaptations of existing water distribution systems (WDS). Since climatic and demographic influences will pose further challenges in the future, the resilience enhancement of 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, metrics based on graph theory have been proposed. In this study, a promising approach is applied to assess the resilience of the WDS for a district in a major German City. The conducted analysis provides insight into the process of actively influencing the resilience of WDS}, language = {en} } @inproceedings{LeiseAltherr2018, author = {Leise, Philipp and Altherr, Lena}, title = {Optimizing the design and control of decentralized water supply systems - a case-study of a hotel building}, series = {EngOpt 2018 Proceedings of the 6th International Conference on Engineering Optimization}, booktitle = {EngOpt 2018 Proceedings of the 6th International Conference on Engineering Optimization}, publisher = {Springer}, address = {Cham}, isbn = {978-3-319-97773-7}, doi = {10.1007/978-3-319-97773-7_107}, pages = {1241 -- 1252}, year = {2018}, abstract = {To increase pressure to supply all floors of high buildings with water, booster stations, normally consisting of several parallel pumps in the basement, are used. In this work, we demonstrate the potential of a decentralized pump topology regarding energy savings in water supply systems of skyscrapers. We present an approach, based on Mixed-Integer Nonlinear Programming, that allows to choose an optimal network topology and optimal pumps from a predefined construction kit comprising different pump types. Using domain-specific scaling laws and Latin Hypercube Sampling, we generate different input sets of pump types and compare their impact on the efficiency and cost of the total system design. As a realistic application example, we consider a hotel building with 325 rooms, 12 floors and up to four pressure zones.}, language = {en} } @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} }