TY - JOUR
A1 - Hagemann, Hans-Jürgen
A1 - Hero, A.
A1 - Gonser, U.
T1 - The valence change of Fe in BaTiO3 studied by Mößbauer effect and gravimetry. Hagemann, H. J.; Hero, A.; Gonser, U.
JF - Physica Status Solidi (A) - Applied Research. 61 (1980)
Y1 - 1980
SN - 0031-8965
SP - 63
EP - 72
ER -
TY - CHAP
A1 - Goeckel, Tom
A1 - Schiffer, Stefan
A1 - Wagner, Hermann
A1 - Lakemeyer, Gerhard
T1 - The Video Conference Tool Robot ViCToR
T2 - Intelligent Robotics and Applications : 8th International Conference, ICIRA 2015, Portsmouth, UK, August 24-27, 2015, Proceedings, Part II
N2 - We present a robotic tool that autonomously follows a conversation to enable remote presence in video conferencing. When humans participate in a meeting with the help of video conferencing tools, it is crucial that they are able to follow the conversation both with acoustic and visual input. To this end, we design and implement a video conferencing tool robot that uses binaural sound source localization as its main source to autonomously orient towards the currently talking speaker. To increase robustness of the acoustic cue against noise we supplement the sound localization with a source detection stage. Also, we include a simple onset detector to retain fast response times. Since we only use two microphones, we are confronted with ambiguities on whether a source is in front or behind the device. We resolve these ambiguities with the help of face detection and additional moves. We tailor the system to our target scenarios in experiments with a four minute scripted conversation. In these experiments we evaluate the influence of different system settings on the responsiveness and accuracy of the device.
Y1 - 2015
SN - 978-3-319-22876-1
U6 - https://doi.org/10.1007/978-3-319-22876-1_6
N1 - Lecture Notes in Computer Science ; 9245
SP - 61
EP - 73
PB - Springer
ER -
TY - JOUR
A1 - Schopp, Christoph
A1 - Britun, Nikolay
A1 - Vorac, Jan
A1 - Synek, Petr
A1 - Snyders, Rony
A1 - Heuermann, Holger
T1 - Thermal and Optical Study on the Frequency Dependence of an Atmospheric Microwave Argon Plasma Jet
JF - IEEE Transactions on Plasma Science
Y1 - 2019
SN - 1939-9375
VL - 47
IS - 7
SP - 3176
EP - 3181
PB - IEEE
CY - New York
ER -
TY - JOUR
A1 - Hagemann, Hans-Jürgen
A1 - Bachmann, P. K.
A1 - Lade, H.
A1 - Leers, D.
T1 - Thermal properties of C/H-, C/H/O-, C/H/N- and C/H/X-grown polycrystalline CVD diamond. P. K. Bachmann, H. J. Hagemann, H. Lade, ...
JF - Diamond and Related Material. Vol 4. (1995), H. Issue 5-6
Y1 - 1995
N1 - abstract online:
SP - 820
EP - 826
PB - Elsevier Science
CY - New York, NY [u.a.]
ER -
TY - CHAP
A1 - Hess, Holger
A1 - Luan, Xuming
A1 - Schwarte, Rudolf
A1 - Zhang, Zhigang
A1 - Xu, Zhanping
A1 - Heinol, Horst-Guenther
A1 - Buxbaum, Bernd
A1 - Ringbeck, Thorsten
ED - Fujisada, Hiroyuki
T1 - Three-dimensional intelligent sensing based on the PMD technology
T2 - Sensors, Systems, and Next-Generation Satellites V : 17 - 20 September 2001, Toulouse, France. - (SPIE proceedings series ; 4540)
Y1 - 2001
SN - 0-8194-4265-8
SN - 0038-7355
SN - 0361-0748
SN - 0277-786X
N1 - Sensors, systems, and next-generation satellites <5, 2001, Toulouse>
SP - 482
EP - 488
PB - SPIE
CY - Bellingham, Wash.
ER -
TY - JOUR
A1 - Köhler, Klemens
A1 - Röpke, René
A1 - Wolf, Martin
T1 - Through a mirror darkly – On the obscurity of teaching goals in game-based learning in IT security
JF - ISAGA 2019: Simulation Gaming Through Times and Disciplines
N2 - Teachers and instructors use very specific language communicating teaching goals. The most widely used frameworks of common reference are the Bloom’s Taxonomy and the Revised Bloom’s Taxonomy. The latter provides distinction of 209 different teaching goals which are connected to methods. In Competence Developing Games (CDGs - serious games to convey knowledge) and in IT security education, a two- or three level typology exists, reducing possible learning outcomes to awareness, training, and education. This study explores whether this much simpler framework succeeds in achieving the same range of learning outcomes. Method wise a keyword analysis was conducted. The results were threefold: 1. The words used to describe teaching goals in CDGs on IT security education do not reflect the whole range of learning outcomes. 2. The word choice is nevertheless different from common language, indicating an intentional use of language. 3. IT security CDGs use different sets of terms to describe learning outcomes, depending on whether they are awareness, training, or education games. The interpretation of the findings is that the reduction to just three types of CDGs reduces the capacity to communicate and think about learning outcomes and consequently reduces the outcomes that are intentionally achieved.
KW - IT security education
KW - Competence Developing Games
KW - Game-based learning
KW - Keyword analysis
KW - Bloom’s Taxonomy
Y1 - 2021
U6 - https://doi.org/10.1007/978-3-030-72132-9_6
N1 - ISAGA 2019 - International Simulation and Gaming Association Conference. 26-30 August 2019. Warsaw, Poland.
Part of the Lecture Notes in Computer Science book series (LNCS, volume 11988)
SP - 61
EP - 73
PB - Springer
CY - Cham
ER -
TY - JOUR
A1 - Orzada, S.
A1 - Maderwald, S.
A1 - Poser, B. A.
A1 - Johst, S.
A1 - Kannengiesser, S.
A1 - Ladd, M. E.
A1 - Bitz, Andreas
T1 - Time-interleaved acquisition of modes: an analysis of SAR and image contrast implications
JF - Magnetic Resonance in Medicine
N2 - s the magnetic field strength and therefore the operational frequency in MRI are increased, the radiofrequency wavelength approaches the size of the human head/body, resulting in wave effects which cause signal decreases and dropouts. Especially, whole-body imaging at 7 T and higher is therefore challenging. Recently, an acquisition scheme called time-interleaved acquisition of modes has been proposed to tackle the inhomogeneity problems in high-field MRI. The basic premise is to excite two (or more) different Burn:x-wiley:07403194:media:MRM23081:tex2gif-stack-1 modes using static radiofrequency shimming in an interleaved acquisition, where the complementary radiofrequency patterns of the two modes can be exploited to improve overall signal homogeneity. In this work, the impact of time-interleaved acquisition of mode on image contrast as well as on time-averaged specific absorption rate is addressed in detail. Time-interleaved acquisition of mode is superior in Burn:x-wiley:07403194:media:MRM23081:tex2gif-stack-2 homogeneity compared with conventional radiofrequency shimming while being highly specific absorption rate efficient. Time-interleaved acquisition of modes can enable almost homogeneous high-field imaging throughout the entire field of view in PD, T2, and T2*-weighted imaging and, if a specified homogeneity criterion is met, in T1-weighted imaging as well.
Y1 - 2012
U6 - https://doi.org/10.1002/mrm.23081
SN - 1522-2594
VL - 67
IS - 4
SP - 1033
EP - 1041
PB - Wiley-Liss
CY - New York
ER -
TY - CHAP
A1 - Ringbeck, Thorsten
A1 - Albrecht, M.
A1 - Frey, J.
A1 - [u.a.],
ED - Lerch, Reinhard
T1 - Time-of-Flight 3D-camera for autonomous navigation and industrial automation
T2 - Proceedings : 11th international conference, 13 - 15 May 2003, Exhibition Centre Nuremberg, Germany ; an event of the Association for Sensor Technology, AMA
Y1 - 2003
N1 - Internationale Messe mit Kongress Sensor
PB - AMA Service
CY - Wunstorf/Germany
ET - CD-ROM-Ausg.
ER -
TY - CHAP
A1 - Ellerweg, Roland
A1 - Ritz, Thomas
ED - Roth, Jörg
T1 - Tool supported requirements analysis for the user centered development of mobile enterprise software
T2 - Proceeding of Wireless Applications and Computing 2008 and Telecommunications, Networks and Systems 2008 : MCCSIS '08 ; IADIS Multi Conference on Computer Science and Information Systems ; 22 - 24 July 2008, Amsterdam, The Netherlands
N2 - A user centered development method has proved satisfactory for the development of mobile enterprise software. To make use of this method, detailed information about the user and the place where the user interacts with his mobile device is required. This article describes how both can be modeled by a stereotypical and conceptual extended UML extension. Finally, a software tool is presented that supports the developed UML extension.
Y1 - 2008
SN - 978-972-8924-62-1
SP - 160
EP - 162
PB - IADIS Press
CY - [Lisboa]
ER -
TY - CHAP
A1 - Schänzle, Christian
A1 - Altherr, Lena
A1 - Ederer, Thorsten
A1 - Pelz, Peter
T1 - TOR – Towards the energetically optimal ventilation system
KW - Energy
KW - Efficiency
KW - Ventilation System
KW - Discrete Optimisation
KW - TGA
Y1 - 2015
N1 - EST 2015, Karlsruhe, 19-21 Mai 2015
ER -
TY - CHAP
A1 - Penne, Jochen
A1 - Profittlich, Martin
A1 - Ringbeck, Thorsten
A1 - Buxbaum, Bernd
ED - D, Nicola D'Apuzzo
T1 - Touchless detailed 3D scan of human hand anatomy using time-of-flight cameras
T2 - Proceedings of the International Conference on 3D Body Scanning Technologies : Lugano, Switzerland, 19-20 October 2010
Y1 - 2010
SN - 978-3-033-02714-5
SP - 361
EP - 369
PB - Hometrica Consulting
CY - Zürich
ER -
TY - CHAP
A1 - Chircu, Alina
A1 - Czarnecki, Christian
A1 - Friedmann, Daniel
A1 - Pomaskow, Johanna
A1 - Sultanow, Eldar
T1 - Towards a Digital Twin of Society
T2 - Proceedings of the 56th Hawaii International Conference on System Sciences 2023
N2 - This paper describes the potential for developing a digital twin of society- a dynamic model that can be used to observe, analyze, and predict the evolution of various societal aspects. Such a digital twin can help governmental agencies and policy makers in interpreting trends, understanding challenges, and making decisions regarding investments or policies necessary to support societal development and ensure future prosperity. The paper reviews related work regarding the digital twin paradigm and its applications. The paper presents a motivating case study- an analysis of opportunities and challenges faced by the German federal employment agency, Bundesagentur f¨ur Arbeit (BA), proposes solutions using digital twins, and describes initial proofs of concept for such solutions.
KW - Digital twin
KW - Digital transformation
KW - Prototype
KW - Society
KW - Stress testing
Y1 - 2023
SN - 978-0-9981331-6-4
N1 - 56th Hawaii International Conference on System Sciences, HICSS 2023, Maui, Hawaii, USA, January 3-6, 2023
SP - 6748
EP - 6757
PB - University of Hawai'i
CY - Honolulu
ER -
TY - JOUR
A1 - Ferrein, Alexander
A1 - Dylla, Frank
A1 - Lakemeyer, Gerhard
A1 - Murray, Jan
T1 - Towards a League-Independent Qualitative Soccer Theory for RoboCup / Dylla, Frank ; Ferrein, Alexander ; Lakemeyer, Gerhard ; Murray, Jan ; Obst, Oliver ; Röfer, Thomas ; Stolzenburg, Frieder ; Visser, Ubbo
JF - RoboCup 2004: Robot Soccer World Cup VIII / Daniele Nardi ... (ed.).
Y1 - 2005
SN - 978-3-540-25046-8
N1 - Lecture Notes in Computer Science ; 3276
SP - 611
EP - 618
PB - Springer
CY - Berlin
ER -
TY - CHAP
A1 - Eichenbaum, Julian
A1 - Nikolovski, Gjorgji
A1 - Mülhens, Leon
A1 - Reke, Michael
A1 - Ferrein, Alexander
A1 - Scholl, Ingrid
T1 - Towards a lifelong mapping approach using Lanelet 2 for autonomous open-pit mine operations
T2 - 2023 IEEE 19th International Conference on Automation Science and Engineering (CASE)
N2 - Autonomous agents require rich environment models for fulfilling their missions. High-definition maps are a well-established map format which allows for representing semantic information besides the usual geometric information of the environment. These are, for instance, road shapes, road markings, traffic signs or barriers. The geometric resolution of HD maps can be as precise as of centimetre level. In this paper, we report on our approach of using HD maps as a map representation for autonomous load-haul-dump vehicles in open-pit mining operations. As the mine undergoes constant change, we also need to constantly update the map. Therefore, we follow a lifelong mapping approach for updating the HD maps based on camera-based object detection and GPS data. We show our mapping algorithm based on the Lanelet 2 map format and show our integration with the navigation stack of the Robot Operating System. We present experimental results on our lifelong mapping approach from a real open-pit mine.
Y1 - 2023
SN - 979-8-3503-2069-5 (Online)
SN - 979-8-3503-2070-1 (Print)
U6 - https://doi.org/10.1109/CASE56687.2023.10260526
N1 - 19th International Conference on Automation Science and Engineering (CASE), 26-30 August 2023, Auckland, New Zealand.
PB - IEEE
ER -
TY - CHAP
A1 - Neumann, Tobias
A1 - Ferrein, Alexander
A1 - Kallweit, Stephan
A1 - Scholl, Ingrid
T1 - Towards a mobile mapping robot for underground mines
T2 - 7th Conference of Robotics and Mechatronics : RobMech 2014 : 27th and 28th Nov. 2014, Cape Town
Y1 - 2014
SP - 1
EP - 6
ER -
TY - JOUR
A1 - Ferrein, Alexander
T1 - Towards applying soccer moves in the RoboCup Standard Platform League
JF - ÖGAI-Journal
Y1 - 2008
SN - 0254-4326
VL - Bd. 27
IS - H. 3
SP - 4
EP - 9
ER -
TY - CHAP
A1 - Niemüller, Tim
A1 - Ewert, Daniel
A1 - Reuter, Sebastian
A1 - Karras, Ulrich
A1 - Ferrein, Alexander
T1 - Towards benchmarking cyber-physical systems in factory automation scenarios
T2 - KI 2013: advances in artificial intelligence : 36th Annual German Conference on AI, Koblenz, Germany, September 16-20, 2013 ; proceedings / Ingo J. Timm ... (ed.). (Lecture notes in computer science ; 8077)
Y1 - 2013
SN - 978-3-642-40941-7
SP - 296
EP - 299
PB - Springer
CY - Berlin [u.a.]
ER -
TY - CHAP
A1 - Serror, Martin
A1 - Henze, Martin
A1 - Hack, Sacha
A1 - Schuba, Marko
A1 - Wehrle, Klaus
T1 - Towards in-network security for smart homes
T2 - 13th International Conference on Availability, Reliability and Security, ARES 2018; Hamburg; Germany; 27 August 2018 through 30 August 2018
Y1 - 2018
SN - 978-145036448-5
U6 - https://doi.org/10.1145/3230833.3232802
SP - Article numer 3232802
ER -
TY - JOUR
A1 - Booysen, Tracy
A1 - Rieger, Michael
A1 - Ferrein, Alexander
T1 - Towards inexpensive robots for science & technology teaching and education in Africa
Y1 - 2011
SN - 978-1-61284-992-8
N1 - AFRICON, 2011
SP - 1
EP - 6
PB - IEEE
CY - New York
ER -
TY - CHAP
A1 - Priede, Gareth
A1 - Ferrein, Alexander
T1 - Towards passive walking for the fully-actuated biped robot Nao
T2 - Emerging trends in computing, informatics, systems sciences, and engineering. (Lecture notes in electrical engineering : vol. 151)
N2 - Many biped robots deploy a form of gait that follows the zero moment point (ZMP) approach, that is, the robot is in a stable position at any point in time. This requires the robot to be fully actuated. While very stable, the draw-backs of this approach are a fairly slow gait and high energy consumption. An alternative approach is the so-called passive-dynamic walking, where the gait makes use of the inertia and dynamic stability of the robot. In this paper we describe our ongoing work of combining the principles of passive-dynamic walking on the fully-actuated biped robot Nao, which is also deployed for robotic soccer applications. We present a simple controller that allows the robot to stably rock sidewards, showing a closed limit-cycle. We discuss first results of superimposing a forward motion on the sidewards motion. Based on this we expect to endow the Nao with a fast, robust, and stable passive-dynamic walk on the fully-actuated Nao in the future.
Y1 - 2013
SN - 978-1-4614-3557-0 ; 978-1-4614-3558-7
U6 - https://doi.org/10.1007/978-1-4614-3558-7_18
SP - 225
EP - 236
PB - Springer
CY - New York, NY
ER -
TY - GEN
A1 - Waiczies, Helmar
A1 - Kühne, André
A1 - Winter, Lukas
A1 - Frauenrath, Tobias
A1 - Hoffmann, Werner
A1 - Ittermann, Bernd
A1 - Waiczies, Sonia
A1 - Niendorf, Thoralf
T1 - Towards theranostics of rheumatoid arthritis: 1H/19F imaging of non-steroidal anti-inflammatory drugs in hand and wrist at 7 Tesla
T2 - 2013 ISMRM Annual Meeting Proceedings
N2 - We have developed a double-tuned ¹H/¹⁹F birdcage resonator dedicated for hand and wrist imaging at 7 T to locally image non-steroidal anti-inflammatory drugs (NSAID) such as 2-{[3-(Trifluoromethyl) phenyl]amino}benzoic acid. The preliminary in vivo images acquired by the double-tuned ¹H/¹⁹F birdcage resonator demonstrate the feasibility for ¹H/¹⁹F hand- and wrist-imaging at 7 T. While the diagnostic quality of the coil needs to be assessed in patients with inflammatory rheumatoid disease, first ¹⁹F images of the NSAID are encouraging, and point towards the prospect of applying ¹⁹F-MRI to visualize and quantify the concentration of therapeutically-active compound at the sites of inflammation.
Y1 - 2013
SN - 1545-4428
N1 - ISMRM 21st Annual Meeting & Exhibition, 20-26 April 2013, Salt Lake City, Utah, USA
ER -
TY - CHAP
A1 - Bensberg, Frank
A1 - Auth, Gunnar
A1 - Czarnecki, Christian
A1 - Wörndle, Christopher
ED - Kemal İlter, H.
T1 - Transforming literature-intensive research processes through text analytics – design, implementation and lessons learned
N2 - 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.
KW - Text analytics
KW - Text mining
KW - Literature review
KW - Research process
Y1 - 2018
U6 - https://doi.org/10.6084/m9.figshare.7582073.v1
N1 - 5th International Management Information Systems Conference.
October 24-26 2018, Ankara
ER -
TY - CHAP
A1 - Ferrein, Alexander
A1 - Bharatheesha, Mukunda
A1 - Schiffer, Stefan
A1 - Corbato, Carlos Hernandez
T1 - TRROS 2018 : Teaching Robotics with ROS Workshop at ERF 2018; Proceedings of the Workshop on Teaching Robotics with ROS (held at ERF 2018), co-located with European Robotics Forum 2018 (ERF 2018), Tampere, Finland, March 15th, 2018
T2 - CEUR Workshop Proceedings
Y1 - 2019
SN - 1613-0073
IS - Vol-2329
ER -
TY - CHAP
A1 - Walter, Michael
A1 - Gligorevic, Snjezana
A1 - Detert, Thorben
A1 - Schnell, Michael
T1 - UHF/VHF air-to-air propagation measurements
T2 - Proceedings of the Fourth European Conference on Antennas and Propagation (EuCAP) : 12 - 16 April 2010, Barcelona, Spain
Y1 - 2010
SN - 978-1-4244-6431-9 ; 978-84-7653-472-4
SP - 1
EP - 5
ER -
TY - JOUR
A1 - Heuermann, Holger
A1 - Sadeghfam, Arash
A1 - Boehm, H.
T1 - Ultra Compact Multi-Mode Filter with Novel Rat-Race Inductor. Sadeghfam, Arash; Heuermann, Holger; Boehm, H.
JF - Conference proceedings : 3 - 7 October 2005, CNIT la Défense, Paris, France; [comprises the] 35th European Microwave Conference 2005 ; The European Conference on Wireless Technology 2005 ; European Radar Conference 2005 ; GAAS 2005, The European Gallium A. Vol. 2
Y1 - 2005
SN - 2-9600551-0-1
N1 - European Microwave Conference ; (35, 2005, Paris) ; European Microwave Week ; (2005, Paris)
SP - 4 pp.
PB - Horizon House Publ
CY - London
ER -
TY - BOOK
A1 - Benkner, Thorsten
A1 - Stepping, Christoph
T1 - UMTS - Universal Mobile Telecommunications System
Y1 - 2002
SN - 3-935340-07-9
PB - Schlembach
CY - Weil der Stadt
ER -
TY - JOUR
A1 - Schuba, Marko
A1 - Busboom, Axel
A1 - Herwono, Ian
A1 - Zavagli, Guido
T1 - Unambiguous Device Identification and Fast Connection Setup in Bluetooth / Busboom, Axel ; Herwono, Ian ; Schuba, Marko ; Zavagli, Guido
JF - European wireless 2002 : next generation wireless networks: technologies, protocols, services and applications ; technical sessions: 26 - 28 February 2002, tutorials: 25 February 2002, Centro Affari, Florence, Italy ; proceedings / sponsored by EUREL ... General chair: Luciano Lenzini
Y1 - 2002
SP - 1
EP - 5
ER -
TY - JOUR
A1 - Ferrein, Alexander
A1 - Jacobs, Stefan
A1 - Lakemeyer, Gerhard
T1 - Unreal Golog Bots / Jacobs, Stefan ; Ferrein, Alexander ; Lakemeyer, Gerhard
JF - IJCAI-05 Workshop on Reasoning, Representation, and Learning in Computer Games
Y1 - 2005
SP - 31
EP - 36
ER -
TY - JOUR
A1 - Foltz, Christian
A1 - Schneider, Nicole
A1 - Wolf, Martin
A1 - Kausch, Bernhard
A1 - Schlick, Christopher
A1 - Luczak, Holger
ED - Nagl, Manfred
T1 - Usability engineering
JF - Collaborative and distributed chemical engineering : from understanding to substantial design process support; results of the IMPROVE Project. - (Lecture notes in computer science ; 4970)
Y1 - 2008
SN - 978-3-540-70552-9
U6 - https://doi.org/10.1007/978-3-540-70552-9_21
SP - 527
EP - 554
PB - Springer
CY - Berlin
ER -
TY - CHAP
A1 - Fuchs, Britta
A1 - Ritz, Thomas
T1 - Usability for Blended Shopping - Solving Major Flaws by Applying Usability Engineering and Proven Integration Technologies
T2 - Proceedings of the 11th International Conference on e-Business, ICE-B 2014, Vienna, Austria
Y1 - 2014
SN - 978-989-758-043-7
U6 - https://doi.org/10.5220/0005113502160223
SP - 216
EP - 223
ER -
TY - CHAP
A1 - Fuchs, Britta
A1 - Ritz, Thomas
A1 - Strauch, Jakob
ED - Obaidat, Mohammad S.
T1 - Usability of mobile applications : dissemination of usability engineering in small and medium enterprises
T2 - Proceedings of the International Conference on Data Communication Networking, e-Business and Optical Communication Systems : Rome, Italy, 24 - 27 July, 2012 ; [integrated in the ICETE (International Conference on e-Business and Telecommunications)]
Y1 - 2012
SN - 978-989-8565-23-5
N1 - Nebentitel: DCNET; ICE-B; OPTICS
SP - 272
EP - 277
PB - SciTePress
CY - [Lissabon]
ER -
TY - JOUR
A1 - Ferrein, Alexander
A1 - Fritz, Christian
A1 - Lakemeyer, Gerhard
T1 - Using Golog for Deliberation and Team Coordination in Robotic Soccer / Ferrein, Alexander ; Fritz, Christian ; Lakemeyer, Gerhard
JF - Künstliche Intelligenz : KI. 19 (2005), H. 1
Y1 - 2005
SN - 0933-1875
SP - 24
EP - 30
ER -
TY - CHAP
A1 - Rausch, Lea
A1 - Friesen, John
A1 - Altherr, Lena
A1 - Pelz, Peter F.
ED - Kliewer, Natalia
ED - Ehmke, Jan Fabian
ED - Borndörfer, Ralf
T1 - Using mixed-integer programming for the optimal design of water supply networks for slums
T2 - Operations Research Proceedings 2017
N2 - 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.
Y1 - 2018
SN - 978-3-319-89919-0 (Print)
SN - 978-3-319-89920-6 (Online)
U6 - https://doi.org/10.1007/978-3-319-89920-6_68
N1 - International Conference of the German Operations Research Society (GOR), Freie Universiät Berlin, Germany, September 6-8, 2017.
SP - 509
EP - 516
PB - Springer
CY - Cham
ER -
TY - JOUR
A1 - Hüning, Felix
T1 - Using Trench PowerMOSFETs in Linear Mode
JF - Power Electronics Europe (2012)
N2 - If we think about applications for modern Power MOSFETs using trench technology, running them in linear mode may not be top of the priority list. Yet there are multiple uses for Trench Power MOSFETs in linear mode. In fact, even turning the device on and off in switching applications is a form of linear operation. Also, these components can be run in linear mode to protect the device against voltage surges. This article will illustrate the factors that need to be considered for linear operation and show how Trench Power MOSFETs are suited to it.
Y1 - 2012
SN - 1748-3530
SP - 27
EP - 29
PB - DFA Media
CY - Tonbridge
ER -
TY - JOUR
A1 - Hagemann, Hans-Jürgen
A1 - Ihrig, H.
T1 - Valence change and phase stability of 3d-doped BaTiO3 annealed in oxygen and hydrogen. Hagemann, H. J.; Ihrig, H.
JF - Physical Review B.. 20 (1979), H. 9
Y1 - 1979
SN - 1095-3795
SP - 3871
EP - 3878
ER -
TY - CHAP
A1 - Müller, Tim M.
A1 - Schmitt, Andreas
A1 - Leise, Philipp
A1 - Meck, Tobias
A1 - Altherr, Lena
A1 - Pelz, Peter F.
A1 - Pfetsch, Marc E.
T1 - Validation of an optimized resilient water supply system
T2 - Uncertainty in Mechanical Engineering
N2 - 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.
KW - Optimization
KW - Mixed-integer nonlinear programming
KW - Water distribution system
KW - Resilience
KW - Validation
Y1 - 2021
SN - 978-3-030-77255-0
SN - 978-3-030-77256-7
U6 - https://doi.org/10.1007/978-3-030-77256-7_7
N1 - Proceedings of the 4th International Conference on Uncertainty in Mechanical Engineering (ICUME 2021), June 7–8, 2021
SP - 70
EP - 80
PB - Springer
CY - Cham
ER -
TY - JOUR
A1 - Yazdanbakhsh, Pedram
A1 - Solbach, Klaus
A1 - Bitz, Andreas
T1 - Variable power combiner for RF mode shimming in 7-T MR imaging
JF - IEEE Transaction on Biomedical Engineering
N2 - This contribution discusses the utilization of RF power in an MRI system with RF mode shimming which enables the superposition of circularly polarized modes of a transmit RF coil array driven by a Butler matrix. Since the required power for the individual modes can vary widely, mode-shimming can result in a significant underutilization of the total available RF power. A variable power combiner (VPC) is proposed to improve the power utilization: it can be realized as a reconfiguration of the MRI transmit system by the inclusion of one additional matrix network which receives the power from all transmit amplifiers at its input ports and provides any desired (combined) power distribution at its output ports by controlling the phase and amplitude of the amplifiers’ input signals. The power distribution at the output ports of the VPC is then fed into the “mode” ports of the coil array Butler matrix in order to superimpose the spatial modes at the highest achievable power utilization. The VPC configuration is compared to the standard configuration of the transmit chain of our MRI system with 8 transmit channels and 16 coils. In realistic scenarios, improved power utilization was achieved from 17% to 60% and from 14% to 55% for an elliptical phantom and a region of interest in the abdomen, respectively, and an increase of the power utilization of 1 dB for a region of interest in the upper leg. In general, it is found that the VPC allows significant improvement in power utilization when the shimming solution demands only a few modes to be energized, while the technique can yield loss in power utilization in cases with many modes required at high power level.
Y1 - 2012
U6 - https://doi.org/10.1109/TBME.2012.2205926
SN - 1558-2531
VL - 59
IS - 9
SP - 2549
EP - 2557
PB - IEEE
CY - New York
ER -
TY - JOUR
A1 - Heuermann, Holger
A1 - Ibrahim, Irfan
A1 - Hillebrand, J.
T1 - Vector-Signal-Generator with Two ¿¿-PLL's / Ibrahim, I. ; Hillebrand, J. ; Heuermann, H.
JF - European Conference on Wireless Technologies, 2007. ECWT 2007 ; 8 - 10 October 2007 Munich, Germany
Y1 - 2007
SN - 978-2-87487-003-3
SP - 1
EP - 4
ER -
TY - JOUR
A1 - Heuermann, Holger
T1 - Verringerung des Phasenrauschens von Oszillatoren durch Dual-Mode-Resonatoren
JF - HF-Report. 20 (2006), H. 5-6
Y1 - 2006
SN - 1431-827X
SP - 43
EP - 48
ER -
TY - JOUR
A1 - Theysohn, Jens M.
A1 - Kraff, Oliver
A1 - Eilers, Kristina
A1 - Andrade, Dorian
A1 - Gerwig, Marcus
A1 - Timmann, Dagmar
A1 - Schmitt, Franz
A1 - Ladd, Mark E.
A1 - Ladd, Susanne C.
A1 - Bitz, Andreas
T1 - Vestibular effects of a 7 Tesla MRI examination compared to 1.5 T and 0 T in healthy volunteers
JF - PLoS one
N2 - Ultra-high-field MRI (7 Tesla (T) and above) elicits more temporary side-effects compared to 1.5 T and 3 T, e.g. dizziness or “postural instability” even after exiting the scanner. The current study aims to assess quantitatively vestibular performance before and after exposure to different MRI scenarios at 7 T, 1.5 T and 0 T. Sway path and body axis rotation (Unterberger's stepping test) were quantitatively recorded in a total of 46 volunteers before, 2 minutes after, and 15 minutes after different exposure scenarios: 7 T head MRI (n = 27), 7 T no RF (n = 22), 7 T only B₀ (n = 20), 7 T in & out B₀ (n = 20), 1.5 T no RF (n = 20), 0 T (n = 15). All exposure scenarios lasted 30 minutes except for brief one minute exposure in 7 T in & out B₀. Both measures were documented utilizing a 3D ultrasound system. During sway path evaluation, the experiment was repeated with eyes both open and closed. Sway paths for all long-lasting 7 T scenarios (normal, no RF, only B₀) with eyes closed were significantly prolonged 2 minutes after exiting the scanner, normalizing after 15 minutes. Brief exposure to 7 T B₀ or 30 minutes exposure to 1.5 T or 0 T did not show significant changes. End positions after Unterberger's stepping test were significantly changed counter-clockwise after all 7 T scenarios, including the brief in & out B₀ exposure. Shorter exposure resulted in a smaller alteration angle. In contrast to sway path, reversal of changes in body axis rotation was incomplete after 15 minutes. 1.5 T caused no rotational changes. The results show that exposure to the 7 Tesla static magnetic field causes only a temporary dysfunction or “over-compensation” of the vestibular system not measurable at 1.5 or 0 Tesla. Radiofrequency fields, gradient switching, and orthostatic dysregulation do not seem to play a role.
Y1 - 2014
U6 - https://doi.org/10.1371/journal.pone.0092104
SN - 1932-6203
VL - 9
IS - 3
PB - PLOS
CY - San Francisco
ER -
TY - CHAP
A1 - Galdi, Chiara
A1 - Hartung, Frank
A1 - Dugelay, Jean-Luc
T1 - Videos versus still images: Asymmetric sensor pattern noise comparison on mobile phones
T2 - Electronic Imaging
N2 - Nowadays, the most employed devices for recoding videos or capturing images are undoubtedly the smartphones. Our work investigates the application of source camera identification on mobile phones. We present a dataset entirely collected by mobile phones. The dataset contains both still images and videos collected by 67 different smartphones. Part of the images consists in photos of uniform backgrounds, especially collected for the computation of the RSPN. Identifying the source camera given a video is particularly challenging due to the strong video compression. The experiments reported in this paper, show the large variation in performance when testing an highly accurate technique on still images and videos.
KW - Image Forensics
KW - Mobile Phones
KW - Image Database
Y1 - 2017
U6 - https://doi.org/10.2352/ISSN.2470-1173.2017.7.MWSF-331
SN - 2470-1173
N1 - IS&T International Symposium on Electronic Imaging 2017
Media Watermarking, Security, and Forensics 2017
SP - 100
EP - 103
PB - Society for Imaging Science and Technology
CY - Springfield, Virginia
ER -
TY - CHAP
A1 - Vladova, Gergana
A1 - Ullrich, André
A1 - Sultanow, Eldar
A1 - Tobolla, Marinho
A1 - Sebrak, Sebastian
A1 - Czarnecki, Christian
A1 - Brockmann, Carsten
T1 - Visual analytics for knowledge management
T2 - INFORMATIK 2023 - Designing Futures: Zukünfte gestalten
N2 - The management of knowledge in organizations considers both established long-term processes and cooperation in agile project teams. Since knowledge can be both tacit and explicit, its transfer from the individual to the organizational knowledge base poses a challenge in organizations. This challenge increases when the fluctuation of knowledge carriers is exceptionally high. Especially in large projects in which external consultants are involved, there is a risk that critical, company-relevant knowledge generated in the project will leave the company with the external knowledge carrier and thus be lost. In this paper, we show the advantages of an early warning system for knowledge management to avoid this loss. In particular, the potential of visual analytics in the context of knowledge management systems is presented and discussed. We present a project for the development of a business-critical software system and discuss the first implementations and results.
Y1 - 2023
SN - 978-3-88579-731-9
U6 - https://doi.org/10.18420/inf2023_187
SN - 1617-5468
N1 - INFORMATIK 2023, 26. - 29. September 2023, Berlin
SP - 1851
EP - 1870
PB - GI - Gesellschaft für Informatik
CY - Bonn
ER -
TY - JOUR
A1 - Elsen, Ingo
A1 - Kraiss, Karl-Friedrich
A1 - Krumbiegel, Dirk
A1 - Walter, Peter
A1 - Wickel, Jochen
T1 - Visual information retrieval for 3D product identification: a midterm report
JF - KI - Künstliche Intelligenz
Y1 - 1999
SN - 1610-1987
SN - 0933-1875
VL - 13
IS - 1
SP - 64
EP - 67
PB - Springer
CY - Berlin
ER -
TY - CHAP
A1 - Kramer, Pia
A1 - Bragard, Michael
A1 - Ritz, Thomas
A1 - Ferfer, Ute
A1 - Schiffers, Tim
T1 - Visualizing, Enhancing and Predicting Students’ Success through ECTS Monitoring
T2 - 2024 IEEE Global Engineering Education Conference (EDUCON)
N2 - This paper serves as an introduction to the ECTS monitoring system and its potential applications in higher education. It also emphasizes the potential for ECTS monitoring to become a proactive system, supporting students by predicting academic success and identifying groups of potential dropouts for tailored support services. The use of the nearest neighbor analysis is suggested for improving data analysis and prediction accuracy.
KW - Monitoring
KW - Engineering education
KW - Data visualization
KW - Accuracy
KW - Data analysis
Y1 - 2024
U6 - https://doi.org/10.1109/EDUCON60312.2024.10578652
SN - 2165-9559
SN - 2165-9567 (eISSN)
N1 - 2024 IEEE Global Engineering Education Conference (EDUCON), 08-11 May 2024, Kos Island, Greece
PB - IEEE
CY - New York, NY
ER -
TY - JOUR
A1 - Hartung, Frank
A1 - Husoy, J. H.
T1 - Wavelet and subband coding of images - A comparative study / Hartung, F. ; Husoy, J. H.
JF - Mathematical imaging: wavelet applications in signal and image processing : 15 - 16 July 1993, San Diego, California / sponsored and publ. by SPIE - the International Society for Optical Engineering. Andrew F. Laine, chair/ed
Y1 - 1993
SN - 081941283X
N1 - SPIE proceedings series ; 2034 ; Society of Photo-Optical Instrumentation Engineers ; Conference ; (1993.07.15-16 : ; San Diego, Calif.)
SP - 242
EP - 253
PB - SPIE
CY - Bellingham, Wash.
ER -
TY - CHAP
A1 - Amir, Malik
A1 - Bauckhage, Christian
A1 - Chircu, Alina
A1 - Czarnecki, Christian
A1 - Knopf, Christian
A1 - Piatkowski, Nico
A1 - Sultanow, Eldar
T1 - What can we expect from quantum (digital) twins?
T2 - Wirtschaftsinformatik 2022 Proceedings
N2 - 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.
KW - Artificial Intelligence
KW - Digital Twin Evolution
KW - Machine Learning
KW - Quantum Computing
KW - Quantum Machine Learning
Y1 - 2022
N1 - 17. Internationale Tagung Wirtschaftsinformatik, 21. – 23. Februar 2022, Nürnberg (online)
SP - 1
EP - 14
PB - AIS Electronic Library (AISeL)
ER -
TY - JOUR
A1 - Ferrein, Alexander
A1 - Schiffer, Stefan
A1 - Booysen, T.
A1 - Stopforth, R.
T1 - Why it is harder to run RoboCup in South Africa: Experiences from German South African collaborations
JF - International Journal of Advanced Robotic Systems
N2 - Robots are widely used as a vehicle to spark interest in science and technology in learners. A number of initiatives focus on this issue, for instance, the Roberta Initiative, the FIRST Lego League, the World Robot Olympiad and RoboCup Junior. Robotic competitions are valuable not only for school learners but also for university students, as the RoboCup initiative shows. Besides technical skills, the students get some project exposure and experience what it means to finish their tasks on time. But qualifying students for future high-tech areas should not only be for students from developed countries. In this article, we present our experiences with research and education in robotics within the RoboCup initiative, in Germany and South Africa; we report on our experiences with trying to get the RoboCup initiative in South Africa going. RoboCup has a huge support base of academic institutions in Germany; this is not the case in South Africa. We present our ‘north–south’ collaboration initiatives in RoboCup between Germany and South Africa and discuss some of the reasons why we think it is harder to run RoboCup in South Africa.
Y1 - 2016
U6 - https://doi.org/10.1177/1729881416662789
SN - 1729-8806
VL - 13
IS - 5
SP - 1
EP - 13
ER -
TY - CHAP
A1 - Wiegner, Jonas
A1 - Volker, Hanno
A1 - Mainz, Fabian
A1 - Backes, Andreas
A1 - Löken, Michael
A1 - Hüning, Felix
T1 - Wiegand-effect-powered wireless IoT sensor node
T2 - ITG-Fb. 303: Sensoren und Messsysteme
N2 - 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.
Y1 - 2022
SN - 978-3-8007-5835-7
N1 - Sensoren und Messsysteme - 21. ITG/GMA-Fachtagung, 10.05.2022 - 11.05.2022 in Nürnberg
SP - 255
EP - 260
PB - VDE Verlag GmbH
CY - Berlin
ER -
TY - GEN
A1 - Wiegner, J.
A1 - Volker, H.
A1 - Mainz, F.
A1 - Backes, A.
A1 - Löken, M.
A1 - Hüning, Felix
T1 - Wiegand-Effect-Powered Wireless IT Sensor Node
N2 - With the growing interest in small distributed sensors for the “Internet of Things”, more attention is being paid to energy harvesting techologies. Reducing or eliminating the need for external power sources or batteries make devices more self-sufficient, more reliable, and reduces maintenance requirements. The Wiegand effect is a proven technology for harvesting small amounts of electrical power from mechanical motion.
Y1 - 2022
N1 - PSMA International Energy Harvesting Workshop ~ 5-7 April 2022, Raleigh, NC, USA
ER -
TY - CHAP
A1 - Pulini, Paola
A1 - Gligorevic, Snjezana
T1 - WIMAX performance in the airport environment
T2 - Multi-carrier systems & solutions 2009. (Lecture notes in electrical engineering ; 41)
N2 - In this paper, the multicarrier physical layers of WiMAX are evaluated in the context of airport data links. The orthogonal frequency-division multiplexing (OFDM) and orthogonal frequency-division multiple-access (OFDMA) cases are applied to the forward link (FL) and reverse link (RL), respectively. The performance of the so called parking and taxi scenarios is presented for airport communications in C-band. Numerical results show that the proposed scheme brings good performance for both the FL and the RL. For the OFDMA case a structure changing called double-tile is also proposed to improve the system performance.
Y1 - 2009
SN - 978-90-481-2529-6 (Print) ; 978-90-481-2530-2 (Online)
SP - 301
EP - 310
PB - Springer
CY - Berlin [u.a.]
ER -