@article{FerreinSteinbauerMcPhillipsetal.2009,
  author    = {Ferrein, Alexander and Steinbauer, Gerald and McPhillips, Graeme and Niem{\"u}ller, Tim and Potgieter, Anet},
  title     = {Team Zadeat 2009 : team report},
  volume    = {6},
  pages     = {1},
  year      = {2009},
  language  = {en}
}
@article{HoltrupSadeghfamHeuermannetal.2014,
  author    = {Holtrup, S. and Sadeghfam, Arash and Heuermann, Holger and Awakowicz, P.},
  title     = {Characterization and optimization technique for microwave-driven high-intensity discharge lamps using hot S-parameters},
  series = {IEEE transactions on microwave theories and techniques},
  volume    = {62},
  journal   = {IEEE transactions on microwave theories and techniques},
  number    = {10},
  publisher = {IEEE},
  address   = {New York},
  issn      = {0018-9480},
  doi       = {10.1109/TMTT.2014.2342652},
  pages     = {2471 -- 2480},
  year      = {2014},
  abstract  = {High-intensity discharge lamps can be driven by radio-frequency signals in the ISM frequency band at 2.45 GHz, using a matching network to transform the impedance of the plasma to the source impedance. To achieve an optimal operating condition, a good characterization of the lamp in terms of radio frequency equivalent circuits under operating conditions is necessary, enabling the design of an efficient matching network. This paper presents the characterization technique for such lamps and presents the design of the required matching network. For the characterization, a high-intensity discharge lamp was driven by a monofrequent large signal at 2.45 GHz, whereas a frequency sweep over 300 MHz was performed across this signal to measure so-called small-signal hot S-parameters using a vector network analyzer. These parameters are then used as an equivalent load in a circuit simulator to design an appropriate matching network. Using the measured data as a black-box model in the simulation results in a quick and efficient method to simulate and design efficient matching networks in spite of the complex plasma behavior. Furthermore, photometric analysis of high-intensity discharge lamps are carried out, comparing microwave operation to conventional operation.},
  language  = {en}
}
@article{AlhwarinFerreinScholl2014,
  author    = {Alhwarin, Faraj and Ferrein, Alexander and Scholl, Ingrid},
  title     = {IR stereo kinect: improving depth images by combining structured light with IR stereo},
  pages     = {1 -- 9},
  year      = {2014},
  language  = {en}
}
@article{BragardvanHoekDeDoncker2012,
  author    = {Bragard, Michael and van Hoek, H. and De Doncker, R. W.},
  title     = {A major design step in IETO concept realization that allows overcurrent protection and pushes limits of switching performance},
  series = {IEEE transactions on power electronics},
  volume    = {27},
  journal   = {IEEE transactions on power electronics},
  number    = {9},
  publisher = {IEEE},
  address   = {New York},
  issn      = {0885-8993},
  doi       = {10.1109/TPEL.2012.2189136},
  pages     = {4163 -- 4171},
  year      = {2012},
  abstract  = {This paper presents the latest prototype of the integrated emitter turn-off thyristor concept, which potentially ranks among thyristor high-power devices like the gate turn-off thyristor and the integrated gate-commutated thyristor (IGCT). Due to modifications of the external driver stage and mechanical press-pack design optimization, this prototype allows for full device characterization. The turn-off capability was increased to 1600 A with an active silicon area of 823mm2 . This leads to a transient peak power of 672.1kW/cm² . Within this paper, measurements and concept assessment are presented and a comparison to state-of-the-art IGCT devices is provided.},
  language  = {en}
}
@article{KoellenspergerBragardPlumetal.2009,
  author    = {K{\"o}llensperger, P. and Bragard, Michael and Plum, T. and De Doncker, R. W.},
  title     = {The dual GCT : new high-power device using optimized GCT technology},
  series = {IEEE transactions on industry applications},
  volume    = {45},
  journal   = {IEEE transactions on industry applications},
  number    = {5},
  issn      = {0093-9994},
  doi       = {10.1109/TIA.2009.2027364},
  pages     = {1754 -- 1762},
  year      = {2009},
  language  = {en}
}
@article{BragardConradvanHoeketal.2011,
  author    = {Bragard, Michael and Conrad, M. and van Hoek, H. and De Doncker, R. W.},
  title     = {The integrated emitter turn-off thyristor (IETO) : an innovative thyristor-based high power semiconductor device using MOS assisted turn-off},
  series = {IEEE transactions on industry applications},
  volume    = {47},
  journal   = {IEEE transactions on industry applications},
  number    = {5},
  publisher = {IEEE},
  address   = {New York},
  issn      = {0093-9994},
  doi       = {10.1109/TIA.2011.2161432},
  pages     = {2175 -- 2182},
  year      = {2011},
  language  = {en}
}
@article{KlingeOttoMuehl2015,
  author    = {Klinge, Uwe and Otto, Jens and M{\"u}hl, Thomas},
  title     = {High Structural Stability of Textile Implants Prevents Pore Collapse and Preserves Effective Porosity at Strain},
  series = {BioMed Research International},
  volume    = {2015},
  journal   = {BioMed Research International},
  issn      = {2314-6133 (Print)},
  doi       = {10.1155/2015/953209},
  pages     = {7 pages},
  year      = {2015},
  language  = {en}
}
@article{SchifferFerreinLakemeyer2015,
  author    = {Schiffer, Stefan and Ferrein, Alexander and Lakemeyer, Gerhard},
  title     = {Abstracting Away Low-Level Details in Service Robotics with Fuzzy Fluents},
  series = {Model-Driven Knowledge Engineering for Improved Software Modularity in Robotics and Automation. Workshop at European Robotics Forum 2015 Vienna, Austria, March 11-13, 2015.},
  journal   = {Model-Driven Knowledge Engineering for Improved Software Modularity in Robotics and Automation. Workshop at European Robotics Forum 2015 Vienna, Austria, March 11-13, 2015.},
  pages     = {1 -- 4},
  year      = {2015},
  language  = {en}
}
@article{LeingartnerMaurerFerreinetal.2016,
  author    = {Leingartner, Max and Maurer, Johannes and Ferrein, Alexander and Steinbauer, Gerald},
  title     = {Evaluation of Sensors and Mapping Approaches for Disasters in Tunnels},
  series = {Journal of Field Robotics},
  volume    = {33},
  journal   = {Journal of Field Robotics},
  number    = {8},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1556-4967},
  doi       = {10.1002/rob.21611},
  pages     = {1037 -- 1057},
  year      = {2016},
  abstract  = {Ground or aerial robots equipped with advanced sensing technologies, such as three-dimensional laser scanners and advanced mapping algorithms, are deemed useful as a supporting technology for first responders. A great deal of excellent research in the field exists, but practical applications at real disaster sites are scarce. Many projects concentrate on equipping robots with advanced capabilities, such as autonomous exploration or object manipulation. In spite of this, realistic application areas for such robots are limited to teleoperated reconnaissance or search. In this paper, we investigate how well state-of-the-art and off-the-shelf components and algorithms are suited for reconnaissance in current disaster-relief scenarios. The basic idea is to make use of some of the most common sensors and deploy some widely used algorithms in a disaster situation, and to evaluate how well the components work for these scenarios. We acquired the sensor data from two field experiments, one from a disaster-relief operation in a motorway tunnel, and one from a mapping experiment in a partly closed down motorway tunnel. Based on these data, which we make publicly available, we evaluate state-of-the-art and off-the-shelf mapping approaches. In our analysis, we integrate opinions and replies from first responders as well as from some algorithm developers on the usefulness of the data and the limitations of the deployed approaches, respectively. We discuss the lessons we learned during the two missions. These lessons are interesting for the community working in similar areas of urban search and rescue, particularly reconnaissance and search.},
  language  = {en}
}
@article{HaagZontarSchleupenetal.2014,
  author    = {Haag, S. and Zontar, D. and Schleupen, Josef and M{\"u}ller, T. and Brecher, C.},
  title     = {Chain of refined perception in self-optimizing assembly of micro-optical systems},
  series = {Journal of sensors and sensor systems},
  volume    = {3},
  journal   = {Journal of sensors and sensor systems},
  number    = {1},
  publisher = {Copernicus Publ.},
  address   = {G{\"o}ttingen},
  issn      = {2194-878X},
  doi       = {10.5194/jsss-3-87-2014},
  pages     = {87 -- 95},
  year      = {2014},
  abstract  = {Today, the assembly of laser systems requires a large share of manual operations due to its complexity regarding the optimal alignment of optics. Although the feasibility of automated alignment of laser optics has been shown in research labs, the development effort for the automation of assembly does not meet economic requirements - especially for low-volume laser production. This paper presents a model-based and sensor-integrated assembly execution approach for flexible assembly cells consisting of a macro-positioner covering a large workspace and a compact micromanipulator with camera attached to the positioner. In order to make full use of available models from computer-aided design (CAD) and optical simulation, sensor systems at different levels of accuracy are used for matching perceived information with model data. This approach is named "chain of refined perception", and it allows for automated planning of complex assembly tasks along all major phases of assembly such as collision-free path planning, part feeding, and active and passive alignment. The focus of the paper is put on the in-process image-based metrology and information extraction used for identifying and calibrating local coordinate systems as well as the exploitation of that information for a part feeding process for micro-optics. Results will be presented regarding the processes of automated calibration of the robot camera as well as the local coordinate systems of part feeding area and robot base.},
  language  = {en}
}
@article{FerreinSchifferBooysenetal.2016,
  author    = {Ferrein, Alexander and Schiffer, Stefan and Booysen, T. and Stopforth, R.},
  title     = {Why it is harder to run RoboCup in South Africa: Experiences from German South African collaborations},
  series = {International Journal of Advanced Robotic Systems},
  volume    = {13},
  journal   = {International Journal of Advanced Robotic Systems},
  number    = {5},
  issn      = {1729-8806},
  doi       = {10.1177/1729881416662789},
  pages     = {1 -- 13},
  year      = {2016},
  abstract  = {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.},
  language  = {en}
}
@article{FerreinSteinbauer2016,
  author    = {Ferrein, Alexander and Steinbauer, Gerald},
  title     = {20 Years of RoboCup - A Subjective Retrospection},
  series = {KI - K{\"u}nstliche Intelligenz},
  volume    = {30},
  journal   = {KI - K{\"u}nstliche Intelligenz},
  number    = {3},
  publisher = {Springer},
  address   = {Berlin},
  issn      = {1610-1987},
  doi       = {10.1007/s13218-016-0449-5},
  pages     = {225 -- 232},
  year      = {2016},
  abstract  = {This summer, RoboCup competitions were held for the 20th time in Leipzig, Germany. It was the second time that RoboCup took place in Germany, 10 years after the 2006 RoboCup in Bremen. In this article, we give an overview on the latest developments of RoboCup and what happened in the different leagues over the last decade. With its 20th edition, RoboCup clearly is a success story and a role model for robotics competitions. From our personal view point, we acknowledge this by giving a retrospection about what makes RoboCup such a success.},
  language  = {en}
}
@article{SchmidtForkmannSinkeetal.2016,
  author    = {Schmidt, K. and Forkmann, K. and Sinke, C. and Gratz, M. and Bitz, Andreas and Bingel, U.},
  title     = {The differential effect of trigeminal vs. peripheral pain stimulation on visual processing and memory encoding is influenced by pain-related fear},
  series = {NeuroImage},
  volume    = {134},
  journal   = {NeuroImage},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1053-8119},
  doi       = {10.1016/j.neuroimage.2016.03.026},
  pages     = {386 -- 395},
  year      = {2016},
  abstract  = {Compared to peripheral pain, trigeminal pain elicits higher levels of fear, which is assumed to enhance the interruptive effects of pain on concomitant cognitive processes. In this fMRI study we examined the behavioral and neural effects of trigeminal (forehead) and peripheral (hand) pain on visual processing and memory encoding. Cerebral activity was measured in 23 healthy subjects performing a visual categorization task that was immediately followed by a surprise recognition task. During the categorization task subjects received concomitant noxious electrical stimulation on the forehead or hand. Our data show that fear ratings were significantly higher for trigeminal pain. Categorization and recognition performance did not differ between pictures that were presented with trigeminal and peripheral pain. However, object categorization in the presence of trigeminal pain was associated with stronger activity in task-relevant visual areas (lateral occipital complex, LOC), memory encoding areas (hippocampus and parahippocampus) and areas implicated in emotional processing (amygdala) compared to peripheral pain. Further, individual differences in neural activation between the trigeminal and the peripheral condition were positively related to differences in fear ratings between both conditions. Functional connectivity between amygdala and LOC was increased during trigeminal compared to peripheral painful stimulation. Fear-driven compensatory resource activation seems to be enhanced for trigeminal stimuli, presumably due to their exceptional biological relevance.},
  language  = {en}
}
@article{BankOrzadaSmitsetal.2015,
  author    = {Bank, Bart L. van de and Orzada, Stephan and Smits, Frits and Lagemaat, Miriam W. and Rodgers, Christopher T. and Bitz, Andreas and Scheenen, Tom W. J.},
  title     = {Optimized (31) P MRS in the human brain at 7 T with a dedicated RF coil setup},
  series = {NMR in Biomedicine},
  volume    = {28},
  journal   = {NMR in Biomedicine},
  number    = {11},
  publisher = {Wiley},
  address   = {Weinheim},
  issn      = {1099-1492},
  doi       = {10.1002/nbm.3422},
  pages     = {1570 -- 1578},
  year      = {2015},
  language  = {en}
}
@article{NoureddineBitzLaddetal.2015,
  author    = {Noureddine, Yacine and Bitz, Andreas and Ladd, Mark E. and Th{\"u}rling, Markus and Ladd, Susanne C. and Schaefers, Gregor and Kraff, Oliver},
  title     = {Experience with magnetic resonance imaging of human subjects with passive implants and tattoos at 7 T: a retrospective study},
  series = {Magnetic Resonance Materials in Physics, Biology and Medicine},
  volume    = {28},
  journal   = {Magnetic Resonance Materials in Physics, Biology and Medicine},
  number    = {6},
  publisher = {Springer},
  address   = {Berlin},
  issn      = {1352-8661},
  doi       = {10.1007/s10334-015-0499-y},
  pages     = {577 -- 590},
  year      = {2015},
  language  = {en}
}
@article{LagemaatBreukelsVosetal.2016,
  author    = {Lagemaat, Miriam W. and Breukels, Vincent and Vos, Eline K. and B., Adam and Uden, Mark J. van and Orzada, Stephan and Bitz, Andreas and Maas, Marnix C. and Scheenen, Tom W. J.},
  title     = {¹H MR spectroscopic imaging of the prostate at 7T using spectral-spatial pulses},
  series = {Magnetic Resonance in Medicine},
  volume    = {75},
  journal   = {Magnetic Resonance in Medicine},
  number    = {3},
  publisher = {International Society for Magnetic Resonance in Medicine},
  issn      = {1522-2594},
  doi       = {10.1002/mrm.25569},
  pages     = {933 -- 945},
  year      = {2016},
  abstract  = {Purpose To assess the feasibility of prostate ¹H MR spectroscopic imaging (MRSI) using low-power spectral-spatial (SPSP) pulses at 7T, exploiting accurate spectral selection and spatial selectivity simultaneously. Methods A double spin-echo sequence was equipped with SPSP refocusing pulses with a spectral selectivity of 1 ppm. Three-dimensional prostate ¹H-MRSI at 7T was performed with the SPSP-MRSI sequence using an 8-channel transmit array coil and an endorectal receive coil in three patients with prostate cancer and in one healthy subject. No additional water or lipid suppression pulses were used. Results Prostate ¹H-MRSI could be obtained well within specific absorption rate (SAR) limits in a clinically feasible time (10 min). Next to the common citrate signals, the prostate spectra exhibited high spermine signals concealing creatine and sometimes also choline. Residual lipid signals were observed at the edges of the prostate because of limitations in spectral and spatial selectivity. Conclusion It is possible to perform prostate ¹H-MRSI at 7T with a SPSP-MRSI sequence while using separate transmit and receive coils. This low-SAR MRSI concept provides the opportunity to increase spatial resolution of MRSI within reasonable scan times.},
  language  = {en}
}
@article{VosLagemaatBarentszetal.2014,
  author    = {Vos, E. K. and Lagemaat, M. W. and Barentsz, J. O. and F{\"u}tterer, J. J. and Zamecnik, P. and Roozen, H. and Orzada, S. and Bitz, Andreas and Maas, M. C. and Scheenen, T. W. J.},
  title     = {Image quality and cancer visibility of T2-weighted Magnetic Resonance Imaging of the prostate at 7 Tesla},
  series = {European Radiology},
  volume    = {24},
  journal   = {European Radiology},
  number    = {8},
  publisher = {Springer},
  address   = {Cham},
  issn      = {1432-1084},
  doi       = {10.1007/s00330-014-3234-6},
  pages     = {1950 -- 1958},
  year      = {2014},
  abstract  = {Objectives To assess the image quality of T2-weighted (T2w) magnetic resonance imaging of the prostate and the visibility of prostate cancer at 7 Tesla (T). Materials \& methods Seventeen prostate cancer patients underwent T2w imaging at 7T with only an external transmit/receive array coil. Three radiologists independently scored images for image quality, visibility of anatomical structures, and presence of artefacts. Krippendorff's alpha and weighted kappa statistics were used to assess inter-observer agreement. Visibility of prostate cancer lesions was assessed by directly linking the T2w images to the confirmed location of prostate cancer on histopathology. Results T2w imaging at 7T was achievable with 'satisfactory' (3/5) to 'good' (4/5) quality. Visibility of anatomical structures was predominantly scored as 'satisfactory' (3/5) and 'good' (4/5). If artefacts were present, they were mostly motion artefacts and, to a lesser extent, aliasing artefacts and noise. Krippendorff's analysis revealed an α = 0.44 between three readers for the overall image quality scores. Clinically significant cancer lesions in both peripheral zone and transition zone were visible at 7T. Conclusion T2w imaging with satisfactory to good quality can be routinely acquired, and cancer lesions were visible in patients with prostate cancer at 7T using only an external transmit/receive body array coil.},
  language  = {en}
}
@article{LagemaatMaasVosetal.2015,
  author    = {Lagemaat, Miriam W. and Maas, Marnix C. and Vos, Eline K. and Bitz, Andreas and Orzada, Stephan and Weiland, Elisabeth and Uden, Mark J. van and Kobus, Thiele and Heerschap, Arend and Scheenen, Tom W. J.},
  title     = {(31) P MR spectroscopic imaging of the human prostate at 7 T: T1 relaxation times, Nuclear Overhauser Effect, and spectral characterization},
  series = {Magnetic Resonance in Medicine},
  volume    = {73},
  journal   = {Magnetic Resonance in Medicine},
  number    = {3},
  publisher = {Wiley},
  address   = {Weinheim},
  issn      = {1522-2594},
  doi       = {10.1002/mrm.25209},
  pages     = {909 -- 920},
  year      = {2015},
  language  = {en}
}
@article{LagemaatVosMaasetal.2014,
  author    = {Lagemaat, Miriam W. and Vos, Eline K. and Maas, Marnix C. and Bitz, Andreas and Orzada, Stephan and Uden, Mark J. van and Kobus, Thiele and Heerschap, Arend and Scheenen, Tom W. J.},
  title     = {Phosphorus magnetic resonance spectroscopic imaging at 7 T in patients with prostate cancer},
  series = {Investigative Radiology},
  volume    = {49},
  journal   = {Investigative Radiology},
  number    = {5},
  publisher = {Lippincott Williams \& Wilkins},
  address   = {Philadelphia, Pa.},
  issn      = {1536-0210},
  doi       = {10.1097/RLI.0000000000000012},
  pages     = {363 -- 372},
  year      = {2014},
  abstract  = {Objectives The aim of this study was to identify characteristics of phosphorus (³¹P) spectra of the human prostate and to investigate changes of individual phospholipid metabolites in prostate cancer through in vivo ³¹P magnetic resonance spectroscopic imaging (MRSI) at 7 T. Materials and Methods In this institutional review board-approved study, 15 patients with biopsy-proven prostate cancer underwent T₂-weighted magnetic resonance imaging and 3-dimensional ³¹P MRSI at 7 T. Voxels were selected at the tumor location, in normal-appearing peripheral zone tissue, normal-appearing transition zone tissue, and in the base of the prostate close to the seminal vesicles. Phosphorus metabolite ratios were determined and compared between tissue types. Results Signals of phosphoethanolamine (PE) and phosphocholine (PC) were present and well resolved in most ³¹P spectra in the prostate. Glycerophosphocholine signals were observable in 43\% of the voxels in malignant tissue, but in only 10\% of the voxels in normal-appearing tissue away from the seminal vesicles. In many spectra, independent of tissue type, 2 peaks resonated in the chemical shift range of inorganic phosphate, possibly representing 2 separate pH compartments. The PC/PE ratio in the seminal vesicles was highly elevated compared with the prostate in 5 patients. A considerable overlap of ³¹P metabolite ratios was found between prostate cancer and normal-appearing prostate tissue, preventing direct discrimination of these tissues. The only 2 patients with high Gleason scores tumors (≥4+5) presented with high PC and glycerophosphocholine levels in their cancer lesions. Conclusions Phosphorus MRSI at 7 T shows distinct features of phospholipid metabolites in the prostate gland and its surrounding structures. In this exploratory study, no differences in ³¹P metabolite ratios were observed between prostate cancer and normal-appearing prostate tissue possibly because of the partial volume effects of small tumor foci in large MRSI voxels.},
  language  = {en}
}
@article{FiedlerLaddBitz2017,
  author    = {Fiedler, Thomas M. and Ladd, Mark E. and Bitz, Andreas},
  title     = {SAR Simulations \& Safety},
  series = {NeuroImage},
  journal   = {NeuroImage},
  number    = {Epub ahead of print},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1053-8119},
  doi       = {10.1016/j.neuroimage.2017.03.035},
  year      = {2017},
  language  = {en}
}