@inproceedings{NonnKalwa, author = {Nonn, Aida and Kalwa, Christoph}, title = {Simulation of ductile crack propagation in high-strength pipeline steel using damage models}, series = {9th International Pipeline Conference 2012 (IPC 2012), Calgary, Canada}, booktitle = {9th International Pipeline Conference 2012 (IPC 2012), Calgary, Canada}, doi = {10.1115/IPC2012-90653}, pages = {7}, abstract = {The performance of engineering design of high-strength steel pipelines has revealed the necessity to revise current design procedures. Therefore, an improved and detailed comprehension of fracture mechanisms and development of failure prediction tools are required in order to derive new design criteria. In last decades the most successful failure prediction tools for steel structures subjected to various type of loading can be encountered in the field of damage mechanics. This paper aims to describe ductile fracture behavior of high-strength steel pipelines by applying three different damage models, Gurson-Tvergaard-Needelman (GTN), Fracture Locus Curve (FLC) and Cohesive Zone (CZ). These models are evaluated regarding their capability to estimate ductile crack propagation in laboratory specimens and linepipe components without adjusting the calibrated parameters. It can be shown that appropriate parameter sets can be identified to reproduce load-deformation and fracture resistance curves accurately. The strain rate effect on the fracture behavior is examined by dynamic tests on the BDWT specimens. Finally, the shortcomings of the applied models are pointed out with the reference to possible extensions and modifications.}, language = {en} } @inproceedings{KeimNonnLenzetal., author = {Keim, Vincent and Nonn, Aida and Lenz, D. and Brinnel, Viktoria and M{\"u}nstermann, Sebastian}, title = {Simulation of the ductile fracture behaviour of high toughness pipeline steels using combined damage models}, series = {Proceedings of the conference on Technology for future and ageing piplines, Ghent, Belgium}, booktitle = {Proceedings of the conference on Technology for future and ageing piplines, Ghent, Belgium}, language = {en} } @inproceedings{SchmidJungbauerRomanoetal., author = {Schmid, Vinzent and Jungbauer, Bastian and Romano, Marco and Ehrlich, Ingo and Gebbeken, Norbert}, title = {Diminution of mass of different types of fibre reinforcements due to thermal load}, series = {Applied Research Conference 2012 - ARC 2012, 25./26. June 2012}, booktitle = {Applied Research Conference 2012 - ARC 2012, 25./26. June 2012}, editor = {Mottok, J{\"u}rgen and Ziemann, Olaf}, publisher = {Shaker}, pages = {231 -- 235}, language = {en} } @inproceedings{SchmidJungbauerRomanoetal., author = {Schmid, Vinzent and Jungbauer, Bastian and Romano, Marco and Ehrlich, Ingo and Gebbeken, Norbert}, title = {The influence of different types of fabrics on the fibre volume content and porosity in basalt fibre reinforced plastics}, series = {2nd Applied Research Conference 2012 - ARC 25./26. June 2012}, booktitle = {2nd Applied Research Conference 2012 - ARC 25./26. June 2012}, editor = {Mottok, J{\"u}rgen and Ziemann, Olaf}, publisher = {Shaker}, pages = {162 -- 165}, abstract = {High quality semi-finished products with reproducible properties of basaltic fibres are hardly available on the market. In order to examine the properties of basalt fibre reinforced plastics high quality specimens are necessary. The fibre volume content and the porosity of the produced specimen are used as the typical criteria to evaluate the achieved quality of the produced material. The effect of the geometrical properties of the different semi-finished products on the fibre volume contents is relatively small whereas the porosity content is considerably affected.}, language = {en} } @inproceedings{SchmidBrulandEhrlichetal., author = {Schmid, Vinzent and Bruland, Matthias and Ehrlich, Ingo and Kastenmeier, Andreas}, title = {Entwicklung und Regelung eines hydraulischen Biegepr{\"u}fstands}, series = {Virtuelle Instrumente in der Praxis 2015 - Begleitband zum 20. VIP-Kongress.}, booktitle = {Virtuelle Instrumente in der Praxis 2015 - Begleitband zum 20. VIP-Kongress.}, editor = {Rahman, Jamal and Heinze, Ronald}, publisher = {VDE-Verlag}, address = {Berlin/Offenbach}, language = {de} } @inproceedings{Weber, author = {Weber, Karsten}, title = {Ethnische Minderheiten und das Recht auf freie Meinungs{\"a}ußerung}, series = {Medientransformationsprozesse, Gesellschaftlicher Wandel und Demokratisierung in Osteuropa, Dokumentation der Jahrestagung des Center for Advanced Central European Studies am 16., 17. und 18. Mai 2001 in Frankfurt (Oder) ; Wie sich die Bilder (an-)gleichen}, booktitle = {Medientransformationsprozesse, Gesellschaftlicher Wandel und Demokratisierung in Osteuropa, Dokumentation der Jahrestagung des Center for Advanced Central European Studies am 16., 17. und 18. Mai 2001 in Frankfurt (Oder) ; Wie sich die Bilder (an-)gleichen}, editor = {Busch, D. and Panasiuk, I. and Schr{\"o}der, Hartmut}, publisher = {Peter Lang}, address = {Frankfurt/Main}, pages = {57 -- 71}, language = {de} } @inproceedings{Weber, author = {Weber, Karsten}, title = {Ethische Leitlinien: inhaltlich oder prozedural?}, series = {Informatik 2003 - Innovative Informatikanwendungen, Band 2 der Beitr{\"a}ge der 33. Jahrestagung der Gesellschaft f{\"u}r Informatik e.V. (GI), 29. September - 2. Oktober 2003 in Frankfurt am Main}, booktitle = {Informatik 2003 - Innovative Informatikanwendungen, Band 2 der Beitr{\"a}ge der 33. Jahrestagung der Gesellschaft f{\"u}r Informatik e.V. (GI), 29. September - 2. Oktober 2003 in Frankfurt am Main}, editor = {Dittrich, Klaus}, publisher = {Gesellschaft f{\"u}r Informatik e.V.}, address = {Bonn}, pages = {188 -- 193}, abstract = {Der neue Entwurf der ethischen Leitlinien nimmt in der Pr{\"a}ambel Bezug auf die Allgemeine Erkl{\"a}rung der Menschenrechte der Vereinten Nationen; außerdem wird mit Artikel 11 die soziale Verantwortung von Informatikerinnen und Informatikern inhaltlich ausformuliert. Infrage steht nun, ob die Explizierung solcher moralischer Forderungen in den ethischen Leitlinien akzeptabel ist oder ob damit nicht deren M{\"o}glichkeiten {\"u}berdehnt werden. Anders ausgedr{\"u}ckt: Sollen die ethischen Leitlinien rein prozedural ausgerichtet sein oder stattdessen konkrete Zielvorgaben formuliert werden? Um diese Frage zu beantworten, werden zun{\"a}chst die genannten Alternativen der Formulierung dargestellt. Dem folgt eine kritische Auseinandersetzung mit dem neuen Artikel 11 und dem Bezug auf die Allgemeine Erkl{\"a}rung der Menschenrechte. Zuletzt werden Gr{\"u}nde und Bedingungen f{\"u}r die Akzeptabilit{\"a}t dieser und gegen eine Aufnahme weitergehender moralischer Forderungen genannt.}, language = {de} } @inproceedings{BittnerHorneckerTwisselmannetal., author = {Bittner, Peter and Hornecker, Eva and Twisselmann, Ute and Weber, Karsten}, title = {Die berufliche Situation informatisch Handelnder in der ethischen Reflexion}, series = {Informatik 2003 - Innovative Informatikanwendungen, Band 2 der Beitr{\"a}ge der 33. Jahrestagung der Gesellschaft f{\"u}r Informatik e.V. (GI), 29. September - 2. Oktober 2003 in Frankfurt am Main}, booktitle = {Informatik 2003 - Innovative Informatikanwendungen, Band 2 der Beitr{\"a}ge der 33. Jahrestagung der Gesellschaft f{\"u}r Informatik e.V. (GI), 29. September - 2. Oktober 2003 in Frankfurt am Main}, editor = {Dittrich, Klaus}, pages = {176 -- 181}, abstract = {Ausgehend von einer Betrachtung des Einflusses von InformatikerInnen und ihren Handlungsmustern auf Arbeitsprozesse und vor dem Hintergrund einer kritischen Auseinandersetzung mit bisherigen berufsethischen Leitlinien wollen wir einen neuen Ansatz wagen, {\"u}ber Informatik und Verantwortung nachzudenken. Eine Rekonstruktion des Begriffs Verantwortung bietet uns ein reichhaltiges begriffliches Instrumentarium zur Reflexion des Verh{\"a}ltnisses von Verantwortung und informatischer Praxis. Wir pl{\"a}dieren daf{\"u}r, dass informatisch Handelnde lernen m{\"u}ssen, ethische Probleme zu erkennen, implizite Annahmen von Arbeitskulturen zu durchschauen und ein Bewusstsein f{\"u}r die Ver{\"a}nderbarkeit dieser Arbeitskulturen entwickeln sollten. Zus{\"a}tzlich bedarf es kollektiver und rechtlicher Ver{\"a}nderungen der Rahmenbedingungen f{\"u}r verantwortliches Handeln.}, language = {de} } @inproceedings{KaesbauerSchmailzlPrehmetal., author = {K{\"a}sbauer, Johannes and Schmailzl, Anton and Prehm, Jens and Loose, Tobias and Hierl, Stefan}, title = {Simulation of Quasi-Simultaneous Laser Transmission Welding of Plastics}, series = {Procedia CIRP}, volume = {94}, booktitle = {Procedia CIRP}, publisher = {Elsevier}, doi = {10.1016/j.procir.2020.09.136}, pages = {737 -- 741}, abstract = {Thermo-mechanical simulation offers great opportunities to optimize welding processes of plastics. For realistic simulation, the temperature dependent mechanical properties need to be implemented from ambient temperature to temperatures above the flow temperature. Standard test methods are insufficient for characterization in the entire temperature range because close to the flow temperature the material is too soft for tensile tests and too stiff for rheometry. Therefore, an optimization strategy is developed, that determines unknown material parameters by testing in welding simulations. The unknown parameters are iteratively adjusted to minimize the mismatch between computed and measured set-paths. Thus, important process characteristics are calculated realistically, enabling the computer aided assessment of the weld quality.}, subject = {Kunststoffschweißen}, language = {en} } @inproceedings{MaiwaldEnglmaierHierl, author = {Maiwald, Frederik and Englmaier, Stephan and Hierl, Stefan}, title = {Online pyrometry for weld seam localization in absorber-free laser transmission welding of transparent polymers}, series = {21st International Symposium on Laser Precision Microfabrication: Dresden, 26.06.2020}, booktitle = {21st International Symposium on Laser Precision Microfabrication: Dresden, 26.06.2020}, publisher = {Japan Laser Processing Society}, abstract = {Optical and medical devices made of transparent polymers are gaining popularity because of its cost advantages. The manufacturing technology must be able to meet the high demands of these applications. Advantages of laser transmission welding - contactless input of energy, precision, no adhesives and no particle formation - can be exploited here. For absorber-free welding, lasers emitting in the polymers' intrinsic absorption spectrum are used. Focusing the laser beam with high NA enables selective fusing of the joining zone. Since a molten upper surface leads to visible and palpable irregularities, the lateral expansion of the weld seam is monitored in this work. Welding tests with 1 mm thick plates of COC are performed and monitored by pyrometry. Distances between seam and surface measured in thin cuts and are compared with the pyrometer signal. This shows that the localization of the weld seam is possible and proper and faulty parts can be distinguished by pyrometry.}, subject = {Laserdurchstrahlschweissen}, language = {en} } @inproceedings{MeusslingSentpali, author = {Meussling-Sentpali, Annette}, title = {"Wer pflegt in Zukunft?"}, series = {Vortrag beim Altenpflegekongress Regensburg am 19.4.2018}, booktitle = {Vortrag beim Altenpflegekongress Regensburg am 19.4.2018}, language = {de} } @inproceedings{MeusslingSentpali, author = {Meussling-Sentpali, Annette}, title = {"Gender, Pflege und Technik"}, series = {Vortrag und Workshop an der HS Landshut am 23.11.2017}, booktitle = {Vortrag und Workshop an der HS Landshut am 23.11.2017}, language = {de} } @inproceedings{MeusslingSentpali, author = {Meussling-Sentpali, Annette}, title = {"Sorge als Gegenstand von Pflege"}, series = {Hauptvortrag beim Netzwerk Existenzielle Kommunikation und Spiritualit{\"a}t in der Pflege in Berlin am 14.6.2016}, booktitle = {Hauptvortrag beim Netzwerk Existenzielle Kommunikation und Spiritualit{\"a}t in der Pflege in Berlin am 14.6.2016}, language = {de} } @inproceedings{MeusslingSentpali, author = {Meussling-Sentpali, Annette}, title = {"Zeichen der Ver{\"a}nderung - Die Sicht der Pflege"}, series = {5. Christlicher Gesundheitskongress 14.-16. April 2016}, booktitle = {5. Christlicher Gesundheitskongress 14.-16. April 2016}, language = {de} } @inproceedings{DorschnerMeusslingSentpali, author = {Dorschner, Stephan and Meussling-Sentpali, Annette}, title = {"Alles hat seine Zeit" - Aufbruch zu einem neuen Pflegeverst{\"a}ndnis}, series = {"Alles hat seine Zeit ..." - Aufbruch zu einem neuen Pflegeverst{\"a}ndnis: Tagungsband zum 2. Christlichen Pflegekongress vom 30. Oktober bis 1. November in Bingen}, booktitle = {"Alles hat seine Zeit ..." - Aufbruch zu einem neuen Pflegeverst{\"a}ndnis: Tagungsband zum 2. Christlichen Pflegekongress vom 30. Oktober bis 1. November in Bingen}, editor = {Dorschner, Stephan and Meussling-Sentpali, Annette}, publisher = {Jenaer Akademische Verlagsgesellschaft}, address = {Jena}, isbn = {978-3-9812008-3-6}, pages = {187 -- 207}, language = {de} } @inproceedings{DorschnerMeusslingSentpali, author = {Dorschner, Stephan and Meussling-Sentpali, Annette}, title = {"Christlich pflegen in unserer Gesellschaft?"}, series = {Elisabeth bewegt - Christen in der Pflege: Tagungsband zum 1. Christlichen Pflegekongress vom 30. Oktober bis 1. November 2007 in Eisenach}, booktitle = {Elisabeth bewegt - Christen in der Pflege: Tagungsband zum 1. Christlichen Pflegekongress vom 30. Oktober bis 1. November 2007 in Eisenach}, editor = {Dorschner, Stephan and Meussling-Sentpali, Annette}, publisher = {Jenaer Akademische Verlagsgesellschaft}, address = {Jena}, isbn = {9783981200805}, pages = {20 -- 37}, language = {de} } @inproceedings{AndersendeZeeDendorferetal., author = {Andersen, Michael Skipper and de Zee, Mark and Dendorfer, Sebastian and MacWilliams, Bruce and Rasmussen, John}, title = {Validation of a detailed lower extremity model based on the Klein Horsman data set}, series = {Proceedings of the 12th International Symposium on Computer Simulation in Biomechanics (ISB 2009), July 2nd - 4th 2009, Cape Town, South Africa}, booktitle = {Proceedings of the 12th International Symposium on Computer Simulation in Biomechanics (ISB 2009), July 2nd - 4th 2009, Cape Town, South Africa}, pages = {27 -- 28}, language = {en} } @inproceedings{DendorferRasmussen, author = {Dendorfer, Sebastian and Rasmussen, John}, title = {The influence of in-vivo muscle forces on the stress distribution in a vertebral body during activities of daily living}, series = {Eurospine Warsaw, Poland 2009}, booktitle = {Eurospine Warsaw, Poland 2009}, language = {en} } @inproceedings{DendorferEnglert, author = {Dendorfer, Sebastian and Englert, Carsten}, title = {Forces on a clavicles midshaft fracture and influence of fracture type}, series = {AO Symposium, Regensburg, 2009}, booktitle = {AO Symposium, Regensburg, 2009}, language = {en} } @inproceedings{DendorferCarbesRasmussen, author = {Dendorfer, Sebastian and Carbes, S. and Rasmussen, John}, title = {The influence of muscle forces on biomechanical fracture fixation simulations - from in-vivo forces to tissue strains}, series = {World Congress on Medical Physics and Biomedical Engineering, 7 - 12, 2009, Munich}, booktitle = {World Congress on Medical Physics and Biomedical Engineering, 7 - 12, 2009, Munich}, language = {en} } @inproceedings{RobieRasmussenChristensenetal., author = {Robie, Bruce and Rasmussen, John and Christensen, Soeren Toerholm and Dendorfer, Sebastian}, title = {Herniation Induces 55\% Increase in Load of Key Stabilizing Muscle - Impact on Herniation Treatment Devices?}, series = {Spine Arthoplasty Society Meeting, New Orleans, 2010}, booktitle = {Spine Arthoplasty Society Meeting, New Orleans, 2010}, language = {en} } @inproceedings{DendorferRasmussenChristensenetal., author = {Dendorfer, Sebastian and Rasmussen, John and Christensen, Soeren Toerholm and Robie, Bruce}, title = {The Effect of Spinal Disc Herniation on Multifidus Muscles}, series = {56th Orthopaedic Research Society Meeting, New Orleans, USA, 2010}, booktitle = {56th Orthopaedic Research Society Meeting, New Orleans, USA, 2010}, language = {en} } @inproceedings{EnglertMuellerDendorfer, author = {Englert, Carsten and M{\"u}ller, F. and Dendorfer, Sebastian}, title = {Einfluss der Muskelkr{\"a}fte, des Bewegungsausmaßes und der Bruchform auf die Kraft{\"u}bertragung des Implantat-Knochenverbundes am Beispiel der Claviculafraktur im mittleren Drittel}, series = {17. Jahreskongress der Deutschen Vereinigung f{\"u}r Schulter- und Ellenbogenchirurgie (DVSE), Rosenheim 2010}, booktitle = {17. Jahreskongress der Deutschen Vereinigung f{\"u}r Schulter- und Ellenbogenchirurgie (DVSE), Rosenheim 2010}, abstract = {Fragestellung Es soll in dieser Computersimulationsstudie untersucht werden, wie der Osteosyntheseverbund Platte mit Schrauben im Verbund mit einer im mittleren Drittel gebrochenen Clavicula durch das Bewegungsausmaß in vivo belastet ist. Was sind die grundlegenden Kr{\"a}fte die auf Clavicula und Implantat wirken und welchen Einfl uss hat die Bruchform. Methodik Die Muskel- und Gelenkkr{\"a}fte sowie die Belastung des Implantatverbundes wurden mit einer muskuloskelletalen Simulationssoftware (AnyBody Technology, V.4) berechnet. Hierf{\"u}r wurden mit einem komplexen Model des menschlichen K{\"o}rpers folgende Bewegungen analysiert: eine Flexion von 160° und Abduktion 160° mit einem Gewicht von 2 kg in der Hand. Aus CT-Patientendaten wurden zwei dreidimensionale Modelle des Clavicula-Implantat Verbundes gebildet, die sich in der Frakturform unterscheiden (Querfraktur und vertikale Fraktur). In beiden Modellen wurde eine Claviculaosteosynthese in superiorer Position mit einer 6 Loch LCP mit 2 Schrauben pro Hauptfragment verwendet. Die Materialeigenschaften wurden aus der Dichte des Materials sowie aus Literaturdaten verwendet. Die Muskel- und Gelenkkr{\"a}fte aus der muskuloskelletalen Berechnung wurden auf das Finite Elemente Modell {\"u}bertragen und die Spannungen und Dehnungen des Implantat-Knochenverbundes wurden berechnet. Ergebnisse Es zeigte sich, dass die simulierte in vivo Belastung stark abh{\"a}ngig vom Flexionswinkel ist. Das Implantat ist in der superioren Lage auf Biegung belastet, welche maximale Werte im {\"U}berschulterniveau erreicht. Die Bruchform mit anatomischer Reposition und Kontakt der Hauptfragmente zueinander f{\"u}hrt zu einer deutlichen Entlastung des Osteosyntheseverbundes im Vergleich zu einer Bruchform mit vertikaler Fraktur. Schlussfolgerung Aus den Analysen ist eine Positionierung der Plattenosteosynthese f{\"u}r die im mittleren Drittel frakturierte Clavicula in anterior-superiorer Lage w{\"u}nschenswert. Die anatomische Reposition entlastet den Osteosyntheseverbund und sollte m{\"o}glichst erreicht werden. Die Nachbehandlung sollte ein Bewegungsausmaß f{\"u}r den Arm f{\"u}r 4 Wochen f{\"u}r einfache Bruchformen auf 70° Flexion und Abduktion limitieren und f{\"u}r komplexe Bruchformen diese Limitierung ausgedehnt werden.}, language = {de} } @inproceedings{HornerDendorferKiisetal., author = {Horner, Marc and Dendorfer, Sebastian and Kiis, Arne and Lawrenchuk, Mike and Verma, Gunjan}, title = {A Patient based simulation workflow for orthopedic device design and analysis}, series = {SBC Ortho Workshop, June 2011}, booktitle = {SBC Ortho Workshop, June 2011}, language = {en} } @inproceedings{RobieDendorferRasmussenetal., author = {Robie, Bruce and Dendorfer, Sebastian and Rasmussen, John and Christensen, Soeren Toerholm}, title = {Axial Rotation Requires Greatest Load in Multifidus Muscle - Potential Association with Low Back Pain?}, series = {Annual Meeting of the AANS/CNS Section on Disorders of the Spine and Peripheral Nerves, 2011, Phoenix, Arizona}, booktitle = {Annual Meeting of the AANS/CNS Section on Disorders of the Spine and Peripheral Nerves, 2011, Phoenix, Arizona}, language = {en} } @inproceedings{RasmussenBichlerChristensenetal., author = {Rasmussen, John and Bichler, R. and Christensen, Soeren Toerholm and Wirix-Speetjens, Roel and Dendorfer, Sebastian and Renkawitz, Tobias}, title = {Subject-specific Musculoskeletal Simulation of Hip Dislocation Risk in Activities of Daily Living}, series = {Proceedings of the 2011 ORS Annual Meeting, Long Beach, CA.}, booktitle = {Proceedings of the 2011 ORS Annual Meeting, Long Beach, CA.}, number = {Paper No. 306}, language = {en} } @inproceedings{GalibarovDendorferChristensen, author = {Galibarov, Pavel E. and Dendorfer, Sebastian and Christensen, Soeren Toerholm}, title = {On modelling spine curvature dependent on muscular and external forces in multibody dynamics system}, series = {International Society of Biomechanics (ISB), 13th congress, 2011, Brussels, Belgium}, booktitle = {International Society of Biomechanics (ISB), 13th congress, 2011, Brussels, Belgium}, pages = {2}, abstract = {This paper presents a computational approach for investigating effect of muscular and external forces on curvature of the lumbar spine. Multibody dynamics system is used to compute the lumbar spine curvature using a force-dependent kinematics facility, e.g. this method allows releasing some degrees of freedom in order to be computed based on the current load configuration.}, language = {en} } @inproceedings{GalibarovAlMunajjedDendorferetal., author = {Galibarov, Pavel E. and Al-Munajjed, Amir Andreas and Dendorfer, Sebastian and Christensen, Soeren Toerholm and Rasmussen, John}, title = {The effect of varying the stiffness of spinal fusion devices on the adjacent levels using multibody dynamics simulation}, series = {Orthopaedic Proceedings}, volume = {94-B}, booktitle = {Orthopaedic Proceedings}, number = {SUPP_XL01 Sep 2012}, pages = {2}, abstract = {INTRODUCTION Several clinical studies demonstrated long-term adjacent-level effects after implantation of spinal fusion devices[1]. These effects have been reported as adjacent joint degeneration and the development of new symptoms correlating with adjacent segment degeneration[2] and the trend has therefore gone to motion preservation devices; however, these effects have not been understood very well and have not been investigated thoroughly[3]. The aim of this study is to investigate the effect of varying the stiffness of spinal fusion devices on the adjacent vertebral levels. Disc forces, moments and facet joint forces were analyzed. METHODS The AnyBody Modeling System was used to compute the in-vivo muscle and joint reaction forces of a musculoskeletal model. The full body model used in this study consists of 188 muscle fascicles in the lumbar spine and more than 1000 individual muscle branches in total. The model has been proposed by de Zee et al.[3], validated by Rasmussen et al.[4] and by Galibarov et al.[5]. The new model[5] determines the individual motions between vertebrae based on the equilibrium between forces acting on the vertebrae from muscles and joints and the passive stiffness in disks and ligaments, figure 1a. An adult of 1.75 m and 75 kg with a spinal implant in L4L5 was modeled. This model was subjected to a flexion-extension motion using different elastic moduli to analyze and compare to a non-implanted scenario. The analyzed variables were vertebral motion, the disc reaction forces and moments, as well as facet joint forces in the treated and the adjacent levels: L2L3, L3L4, L4L5 and L5-Sacrum. RESULTS When introducing a spinal fusion device in the L4L5 joint the reaction forces and moments decreased in this joint with stiffer devices leading to lower joint loads. However, in the adjacent joints, L3L4 and L5Sacrum, an increase was observed when implanting stiffer devices. Similar trends could be found for the L2L3 joint. The loads in the facet joints showed the same trends. While introducing a spinal fusion device reduced the facet joint forces in the treated joint, the loads in the adjacent facet joints were increased according to the stiffness of the implanted device, figure 1b. DISCUSSION While the treated disc joint showed reduced motion and loads, the adjacent levels demonstrated a significant increase. In particular, the increased facet joint forces in the adjacent levels can lead to adjacent level facet pain or accelerated facet joint degeneration. Introducing a device resulted in preventing facet contact and therefore facet joint loads, even using the device with the lowest stiffness. CONCLUSION The presented model shows that clinical complications such as facet joint degeneration in adjacent levels after implantation of spinal fusion device are consistent with the change in the mechanical-stimulus distribution in the system.}, language = {en} } @inproceedings{GalibarovDendorferRasmussen, author = {Galibarov, Pavel E. and Dendorfer, Sebastian and Rasmussen, John}, title = {Two Computational Models of the Lumbar Spine:}, series = {Proceedings of the 2011 ORS Annual Meeting, Long Beach, CA, vol. Marie Curie Initial Training Network "SpineFX"}, booktitle = {Proceedings of the 2011 ORS Annual Meeting, Long Beach, CA, vol. Marie Curie Initial Training Network "SpineFX"}, language = {en} } @inproceedings{PutzerWeberDendorfer, author = {Putzer, Michael and Weber, Tim and Dendorfer, Sebastian}, title = {Design studies on hip prosthesis using patient specific data}, series = {Simpleware Users meeting, November 9th 2011, Bristol, UK}, booktitle = {Simpleware Users meeting, November 9th 2011, Bristol, UK}, language = {en} } @inproceedings{WeberDendorferRenkawitzetal., author = {Weber, Tim and Dendorfer, Sebastian and Renkawitz, Tobias and Dullien, Silvia and Grifka, Joachim}, title = {Clinical gait analysis combined with musculoskeletal modelling - coding a new generation of evaluation instruments}, series = {Deutsche Gesellschaft f{\"u}r Biomechanik, Murnau, 2011}, booktitle = {Deutsche Gesellschaft f{\"u}r Biomechanik, Murnau, 2011}, language = {en} } @inproceedings{Dendorfer, author = {Dendorfer, Sebastian}, title = {The effect of multifidus muscles atrophy following disc herniation on disc loading}, series = {Deutsche Gesellschaft f{\"u}r Biomechanik, Murnau, 2011}, booktitle = {Deutsche Gesellschaft f{\"u}r Biomechanik, Murnau, 2011}, language = {en} } @inproceedings{SpreiterGalibarovDendorferetal., author = {Spreiter, G. and Galibarov, Pavel E. and Dendorfer, Sebastian and Ferguson, Stephen J.}, title = {Influence of kyphosis on spinal loading}, series = {10th International Symposium Computer Methods in Biomechanics and Biomedical Engineering (CMBBE) Meeting, 11. - 14. April 2012, Berlin}, booktitle = {10th International Symposium Computer Methods in Biomechanics and Biomedical Engineering (CMBBE) Meeting, 11. - 14. April 2012, Berlin}, language = {en} } @inproceedings{WeberStezowskiDullienetal., author = {Weber, Tim and Stezowski, P. and Dullien, Silvia and Dendorfer, Sebastian}, title = {Eine biomechanische Bewertung verschiedener Belastungsszenarios nach der Implantierung einer H{\"u}ft-Totalendoprothese}, series = {89. Jahrestagung der Vereinigung der Bayerischen Chirurgen e.V., 25. - 27. Juli 2012, Regensburg}, booktitle = {89. Jahrestagung der Vereinigung der Bayerischen Chirurgen e.V., 25. - 27. Juli 2012, Regensburg}, language = {de} } @inproceedings{WeberStezowskiDullienetal., author = {Weber, Tim and Stezowski, P. and Dullien, Silvia and Putzer, Michael and Dendorfer, Sebastian}, title = {Eine biomechanische Bewertung verschiedener Belastungsszenarien nach Implantierung einer H{\"u}ft-Totalendoprothese}, series = {GAMMA Workshop, Hannover, 2012}, booktitle = {GAMMA Workshop, Hannover, 2012}, language = {de} } @inproceedings{WeberDullienPutzeretal., author = {Weber, Tim and Dullien, Silvia and Putzer, Michael and Dendorfer, Sebastian and Renkawitz, Tobias}, title = {Biomechanical outcome after computer-assisted vs. conventional THR - study concept and preliminary gait analysis results}, series = {GAMMA Workshop, Hannover, 2012}, booktitle = {GAMMA Workshop, Hannover, 2012}, language = {en} } @inproceedings{PutzerGalibarovDendorfer, author = {Putzer, Michael and Galibarov, Pavel E. and Dendorfer, Sebastian}, title = {Influence of vertebral parameters on lumbar spine loading}, series = {Pre-meeting SpineFX, Eurospine 2013, Liverpool, UK}, booktitle = {Pre-meeting SpineFX, Eurospine 2013, Liverpool, UK}, language = {en} } @inproceedings{Dendorfer, author = {Dendorfer, Sebastian}, title = {Einf{\"u}hrung in die Mechanik}, series = {Biomechanik Workshop, Klinikum Bad Abbach, Nov. 2013}, booktitle = {Biomechanik Workshop, Klinikum Bad Abbach, Nov. 2013}, language = {de} } @inproceedings{DendorferPenzkofer, author = {Dendorfer, Sebastian and Penzkofer, Rainer}, title = {Experimentelle Untersuchung der Belastungen im Kopf beim Treten}, series = {Fachsymposium "Treten gegen den Kopf", April 2013, N{\"u}rnberg}, booktitle = {Fachsymposium "Treten gegen den Kopf", April 2013, N{\"u}rnberg}, language = {de} } @inproceedings{Dendorfer, author = {Dendorfer, Sebastian}, title = {Innovationen in der Medizintechnik}, series = {Oberpfalztag Weiherhammer, Nov. 2013}, booktitle = {Oberpfalztag Weiherhammer, Nov. 2013}, language = {de} } @inproceedings{PutzerPenzkoferEhrlichetal., author = {Putzer, Michael and Penzkofer, Rainer and Ehrlich, Ingo and Rasmussen, John and Gebbeken, Norbert and Dendorfer, Sebastian}, title = {Musculoskeletal simulations to investigate the influence of vertebral geometrical parameters on lumbar spine loading}, series = {7th World Congress of Biomechanics, Boston, United States, 04/07/14 -11/07/14}, booktitle = {7th World Congress of Biomechanics, Boston, United States, 04/07/14 -11/07/14}, language = {de} } @inproceedings{WeberDendorferBulstraetal., author = {Weber, Tim and Dendorfer, Sebastian and Bulstra, Sjoerd K. and Verkerke, Gijsbertus Jacob and Renkawitz, Tobias}, title = {Biomechanical Outcome after computer-assisted vs. Conventional THR}, series = {ANSYS Conference \& 32th CADFEM Users' Meeting 2014, 04.-06. Juni, N{\"u}rnberg}, booktitle = {ANSYS Conference \& 32th CADFEM Users' Meeting 2014, 04.-06. Juni, N{\"u}rnberg}, language = {en} } @inproceedings{AlMunajjedNolteRasmussenetal., author = {Al-Munajjed, Amir Andreas and Nolte, Daniel and Rasmussen, John and Dendorfer, Sebastian}, title = {Force distribution in the foot during braking - a musculoskeletal approach}, series = {Human Modeling Symposium 2014, Munich, Germany}, booktitle = {Human Modeling Symposium 2014, Munich, Germany}, abstract = {High loads can appear in the individual joints of the human foot while the driver uses the pedals, in particular, during breaking. Measuring these internal forces is very difficult or almost impossible; therefore, advanced models are necessary to perform musculoskeletal simulations. The objective of this investigation was to see what loads are acting in the individual foot joints from the phalanges to calcaneus and talus during different brake scenarios. The Glasgow-Maastricht AnyBody Foot Model with 26 separate segments, connected by joints, ligaments and muscles was used inside the AnyBody Modeling System to compute individual mid foot joint loads. The amount, the direction of the force and additionally also the load insertion point was varied for several simulations. Figure 1: Seated musculoskeletal body model with applied brake force and forces for the lateral, intermediate and medial cuneiform-navicular joint for two different brake forces. The simulation showed that for the different brake scenarios, different muscles will be activated in the human and therefore different loads are apply in the fore-and mid-foot, respectively. The torso of the subject was assumed to be fixed in the seat. Further studies are ongoing to simulate the seat as an elastic element that allows different H-point locations according to the different loadings in the foot from the brake pedal using a new inverse dynamics analysis method called force-dependent kinematics.}, language = {en} } @inproceedings{StrieglKujatDendorfer, author = {Striegl, B. and Kujat, Richard and Dendorfer, Sebastian}, title = {Quantitative analysis of cartilage surface by confocal laser scanning microscopy}, series = {Biomedizinische Technik}, volume = {59}, booktitle = {Biomedizinische Technik}, number = {s1-A}, doi = {10.1515/bmt-2014-4012}, pages = {24}, language = {en} } @inproceedings{Dendorfer, author = {Dendorfer, Sebastian}, title = {Mechanobiology - Impact on regeneration and degradation}, series = {Translations in Regenerative Medicine, TIRM and FIFA Symposium, Regensburg, 2015}, booktitle = {Translations in Regenerative Medicine, TIRM and FIFA Symposium, Regensburg, 2015}, language = {en} } @inproceedings{WeberDendorferBulstraetal., author = {Weber, Tim and Dendorfer, Sebastian and Bulstra, Sjoerd K. and Verkerke, Gijsbertus Jacob and Renkawitz, Tobias}, title = {Musculoskeletal modeling for orthopedic surgery - Applications and chances}, series = {Orthopedics meets Engineering, Regensburg, 2015}, booktitle = {Orthopedics meets Engineering, Regensburg, 2015}, language = {en} } @inproceedings{WeberDendorferBulstraetal., author = {Weber, Tim and Dendorfer, Sebastian and Bulstra, Sjoerd K. and Grifka, Joachim and Verkerke, Gijsbertus Jacob and Renkawitz, Tim}, title = {Navigated Femur First Total Hip Arthroplasty leads to improved Biomechanical Outcome after surgery}, series = {ORS annual meeting, Las Vegas, USA, 2015}, booktitle = {ORS annual meeting, Las Vegas, USA, 2015}, language = {en} } @inproceedings{SuessPutzerDendorfer, author = {S{\"u}ß, Franz and Putzer, Michael and Dendorfer, Sebastian}, title = {Numerische und experimentelle Untersuchungen an der Wirbels{\"a}ule}, series = {Forschungssymposium Bad Abbach, Germany, 2015}, booktitle = {Forschungssymposium Bad Abbach, Germany, 2015}, language = {de} } @inproceedings{BillingGoetzWeberetal., author = {Billing, A. and G{\"o}tz, J. and Weber, Tim and Dendorfer, Sebastian}, title = {Positionsanalyse von winkelstabilen Plattenosteosynthesesystemen zur Versorgung von Metatarsalfrakturen mit Hilfe von patientenspezifischen biomechanischen Modellen}, series = {Vereinigung S{\"u}ddeutscher Orthop{\"a}den und Unfallchirurgen Jahrestagung 2015, Baden-Baden, Germany}, booktitle = {Vereinigung S{\"u}ddeutscher Orthop{\"a}den und Unfallchirurgen Jahrestagung 2015, Baden-Baden, Germany}, language = {de} } @inproceedings{PutzerDendorfer, author = {Putzer, Michael and Dendorfer, Sebastian}, title = {Sensitivity of lumbar spine loading to anatomical parameters}, series = {International Workshop on Spine Loading and Deformation: From Loading to Recovery, 2-4 July 2015, Julius Wolff Institute, Charit{\´e}-Universitatsmedizin Berlin, Germany}, booktitle = {International Workshop on Spine Loading and Deformation: From Loading to Recovery, 2-4 July 2015, Julius Wolff Institute, Charit{\´e}-Universitatsmedizin Berlin, Germany}, language = {en} } @inproceedings{IgnasiakDendorferFerguson, author = {Ignasiak, Dominika and Dendorfer, Sebastian and Ferguson, Stephen J.}, title = {Thoracolumbar spine model with articulated rigcage for the prediction of dynamic spinal loading}, series = {International Workshop on Spine Loading and Deformation: From Loading to Recovery, 2-4 July 2015, Julius Wolff Institute, Charit{\´e}-Universitatsmedizin Berlin, Germany}, booktitle = {International Workshop on Spine Loading and Deformation: From Loading to Recovery, 2-4 July 2015, Julius Wolff Institute, Charit{\´e}-Universitatsmedizin Berlin, Germany}, language = {en} } @inproceedings{WeberRenkawitzBulstraetal., author = {Weber, Tim and Renkawitz, Tobias and Bulstra, Sjoerd K. and Grifka, Joachim and Verkerke, Gijsbertus Jacob and Dendorfer, Sebastian}, title = {Biomechanics of computer-assisted vs. conventional THR after one year follow up}, series = {XXV Congress of the International Society of Biomechanics, Glasgow, UK, 12th-16th July 2015}, booktitle = {XXV Congress of the International Society of Biomechanics, Glasgow, UK, 12th-16th July 2015}, language = {en} } @inproceedings{PenzkoferGrechenigKujatetal., author = {Penzkofer, Rainer and Grechenig, S. and Kujat, Richard and Angele, Peter and Dendorfer, Sebastian}, title = {Biomechanical comparison of the dorsal femur condyles and the iliac crest in terms of failure behavior}, series = {XXV Congress of the International Society of Biomechanics, Glasgow, UK, 12th-16th July 2015}, booktitle = {XXV Congress of the International Society of Biomechanics, Glasgow, UK, 12th-16th July 2015}, language = {en} } @inproceedings{WeberRenkawitzGrifkaetal., author = {Weber, Tim and Renkawitz, Tobias and Grifka, Joachim and Bulstra, Sjoerd K. and Verkerke, Gijsbertus Jacob and Dendorfer, Sebastian}, title = {The musculoskeletal load scenario of computer-assisted Femur-First THR up to one year after surgery}, series = {VI International Conference on Computational Bioengineering, Barcelona, Sept. 2015}, booktitle = {VI International Conference on Computational Bioengineering, Barcelona, Sept. 2015}, language = {en} } @inproceedings{WeberDendorferGrifkaetal., author = {Weber, Tim and Dendorfer, Sebastian and Grifka, Joachim and Weber, Markus and W{\"o}rner, Michael and Dullien, Silvia and Verkerke, Gijsbertus Jacob and Renkawitz, Tobias}, title = {Verbessert die computerassistierte Femur First Operationstechnik f{\"u}r die H{\"u}ftendoprothetik den muskuloskelettalen Lastfall auf das H{\"u}ftgelenk?}, series = {DKOU 2015, Deutscher Kongress f{\"u}r Orthop{\"a}die und Unfallchirurgie 2015}, booktitle = {DKOU 2015, Deutscher Kongress f{\"u}r Orthop{\"a}die und Unfallchirurgie 2015}, language = {de} } @inproceedings{Dendorfer, author = {Dendorfer, Sebastian}, title = {Biomechanik des Alterns}, series = {Kolpingfortbildung Lambach, April 2016}, booktitle = {Kolpingfortbildung Lambach, April 2016}, language = {de} } @inproceedings{Dendorfer, author = {Dendorfer, Sebastian}, title = {Virtuelle Menschmodelle - von der Bewegung zur Belastung}, series = {Medbo Bezirksklinikum Regensburg, April 2016}, booktitle = {Medbo Bezirksklinikum Regensburg, April 2016}, language = {de} } @inproceedings{GrossSuessVerkerkeetal., author = {Gross, Simon and S{\"u}ß, Franz and Verkerke, Gijsbertus Jacob and Dendorfer, Sebastian}, title = {Simulating fatigue in musculoskeletal models using surface electromyography, ECCOMAS Congress, Crete, Greece, 201}, series = {ECCOMAS Congress, Crete, Greece, 2016}, booktitle = {ECCOMAS Congress, Crete, Greece, 2016}, language = {en} } @inproceedings{SuessKubowitschVerkerkeetal., author = {S{\"u}ß, Franz and Kubowitsch, Simone and Verkerke, Gijsbertus Jacob and Dendorfer, Sebastian}, title = {The influence of stress on spinal loading}, series = {ESEM webconference, Dez. 2017}, booktitle = {ESEM webconference, Dez. 2017}, language = {en} } @inproceedings{MuehlingEnglertDendorfer, author = {Muehling, M. and Englert, Carsten and Dendorfer, Sebastian}, title = {Influence of biceps tenotomy and tenodesis on post-operative shoulder strength}, series = {Jahrestagung der Deutschen Gesellschaft f{\"u}r Biomechanik, March 2017, Hannover, Germany}, booktitle = {Jahrestagung der Deutschen Gesellschaft f{\"u}r Biomechanik, March 2017, Hannover, Germany}, language = {en} } @inproceedings{KubowitschSuessJansenetal., author = {Kubowitsch, Simone and S{\"u}ß, Franz and Jansen, Petra and Dendorfer, Sebastian}, title = {Muscular imbalances during experimentally induced stress}, series = {23th Congress of the European Society of Biomechanics, Sevilla, Spain, 2017}, booktitle = {23th Congress of the European Society of Biomechanics, Sevilla, Spain, 2017}, language = {en} } @inproceedings{SuessKubowitschVerkerkeetal., author = {S{\"u}ß, Franz and Kubowitsch, Simone and Verkerke, Gijsbertus Jacob and Dendorfer, Sebastian}, title = {The influence of mental stress on spinal disc loading and muscle activity}, series = {23th Congress of the European Society of Biomechanics, Sevilla, Spain, 2017}, booktitle = {23th Congress of the European Society of Biomechanics, Sevilla, Spain, 2017}, language = {en} } @inproceedings{GrossVerkerkeDendorfer, author = {Gross, Simon and Verkerke, Gijsbertus Jacob and Dendorfer, Sebastian}, title = {Investigation of external load dependent static and dynamic muscle fatigue}, series = {23th Congress of the European Society of Biomechanics, Sevilla, Spain, 2017}, booktitle = {23th Congress of the European Society of Biomechanics, Sevilla, Spain, 2017}, language = {en} } @inproceedings{PillingSuessKubowitschetal., author = {Pilling, A. and S{\"u}ß, Franz and Kubowitsch, Simone and Dendorfer, Sebastian}, title = {Experimental workflow for determining psychological stress from physiological biosignals}, series = {Jahrestagung der BIOMEDIZINISCHEN TECHNIK und Dreil{\"a}ndertagung der MEDIZINISCHEN PHYSIK, Dresden, Germany, 2017}, booktitle = {Jahrestagung der BIOMEDIZINISCHEN TECHNIK und Dreil{\"a}ndertagung der MEDIZINISCHEN PHYSIK, Dresden, Germany, 2017}, language = {en} } @inproceedings{JungtaeublAurbachMelzneretal., author = {Jungt{\"a}ubl, Dominik and Aurbach, Maximilian and Melzner, Maximilian and Spicka, Jan and S{\"u}ß, Franz and Dendorfer, Sebastian}, title = {EMG-Based Validation of Musculoskeletal Models Considering Crosstalk}, series = {International Conference BIOMDLORE, June 28 - 30 2018, Białystok, Poland}, booktitle = {International Conference BIOMDLORE, June 28 - 30 2018, Białystok, Poland}, doi = {10.1109/BIOMDLORE.2018.8467211}, abstract = {BACKGROUND: Validation and verification of multibody musculoskeletal models sEMG is a difficult process because of the reliability of sEMG data and the complex relationship of muscle force and sEMG. OBJECTIVE: This work aims at comparing experimentally recorded and simulated muscle activities considering a numerical model for crosstalk. METHODS: For providing an experimentally derived reference data set, subjects were performing elevations of the arm, where the activities of the contemplated muscle groups were measured by sEMG sensors. Computed muscle activities were further processed and transformed into an artificial electromyographical signal, which includes a numerical crosstalk model. In order to determine whether the crosstalk model provides a better agreement with the measured muscle activities, the Pearson correlation coefficient has been computed as a qualitative way of assessing the curve progression of the data sets. RESULTS: The results show an improvement in the correlation coefficient between the experimental data and the simulated muscle activities when taking crosstalk into account. CONCLUSIONS: Although the correlation coefficient increased when the crosstalk model was utilized, it is questionable if the discretization of both, the crosstalk and the musculoskeletal model, is accurate enough.}, language = {en} } @inproceedings{KubowitschSuessJansenetal., author = {Kubowitsch, Simone and S{\"u}ß, Franz and Jansen, Petra and Dendorfer, Sebastian}, title = {Comparison of dynamic muscular imbalances in back pain patients and healthy controls}, series = {World Congress Biomechanics Dublin, 2018}, booktitle = {World Congress Biomechanics Dublin, 2018}, language = {en} } @inproceedings{GrossVerkerkeDendorfer, author = {Gross, Simon and Verkerke, Gijsbertus Jacob and Dendorfer, Sebastian}, title = {Combined Experimental and Numerical Approach to Investigate Changes in Muscle Recruitment Pattern of the Back Muscles during Exhausting Exercise}, series = {World Congress Biomechanics Dublin, 2018}, booktitle = {World Congress Biomechanics Dublin, 2018}, abstract = {In recent years, musculoskeletal computation has become a widely used tool to investigate joint and muscle forces within the human body. However, the issue of muscle fatigue is not considered adequately in most models and is a challenging task. One aspect that needs to be examined is the interaction of muscles during an exhausting task. Therefore, an experimental study was designed to analyze the changes of back muscle recruitment pattern during such exercises. In this study 38 subjects (27 male, 11 female, height = 177±8.5 cm, weight = 74.0±13.6 kg) participated. Each subject had to perform three static and three dynamic exhausting exercises where the back muscles were loaded with subject specific forces using a dynamometer adapter especially designed for the trunk muscles. To collect the muscle activity, twelve surface electromyography sensors were applied on the back, and four on the abdominal muscles. Muscle activity and fatigue were analyzed by calculating the maximum voluntary contraction normalized signal and the median frequency. At first the fatigue of m. erector spinae and m. multifidi was analyzed, since these muscles carry the main load during the exercises. Subsequently the activity of the m. trapezius, m. rectus abdominis and m. obliquus externus were investigated to determine recruitment patterns. To gain more detailed information of these patterns a numerical model was built using the AnyBody Modeling System™. Analyzing the measurements, we can observe an increasing muscle activity during isokinetic exercises while the force is constant. Since the activity in the simulation is defined as the current force output divided by the strength of the muscle, the strength parameter was scaled down based on the measured data, assuming a linear force - activity correlation, and using a numerical algorithm considering the influence of cross talk. The results show, that changes in recruitment pattern can be divided into three major subgroups. Prior to total exhaustion, some of the subjects show additional activation of muscles in the trapezius region, while other subjects show an additional activation of abdominal muscles, increasing the intra-abdominal pressure which supports the spine. In the third group an activation in both regions can be observed. The numerical simulations show an increasing activity of abdominal muscles as well as muscles in the upper back. Especially the m. latissimus dorsi shows a significantly higher activity. The results lead to the conclusion that prior to total exhaustion, additional muscles are recruited to support the main muscles. It was shown that abdominal muscles are activated to support back muscles by pressurizing the trunk cavity to delay total exhaustion as long as possible. In conclusion, the results show that changes in muscle recruitment pattern need to be considered when introducing muscle fatigue to musculoskeletal models.}, language = {en} } @inproceedings{SeefriedAurbachWyssetal., author = {Seefried, C. and Aurbach, Maximilian and Wyss, C. and Dendorfer, Sebastian}, title = {Achilles tendon lengthening alters stresses in the growth plate}, series = {International Conference BIOMDLORE, June 28 - 30 2018, Białystok, Poland}, booktitle = {International Conference BIOMDLORE, June 28 - 30 2018, Białystok, Poland}, language = {en} } @inproceedings{SuessKubowitschVerkerkeetal., author = {S{\"u}ß, Franz and Kubowitsch, Simone and Verkerke, Gijsbertus Jacob and Dendorfer, Sebastian}, title = {Investigation of cognitive stress induced changes in spinal disc forces due to altered kinematics and muscle activity}, series = {World Congress Biomechanics, Dublin, 2018}, booktitle = {World Congress Biomechanics, Dublin, 2018}, language = {en} } @inproceedings{KubowitschDendorfer, author = {Kubowitsch, Simone and Dendorfer, Sebastian}, title = {Psychologie und Biomechanik - Integrierte Betrachtung von Muskelrekrutierung}, series = {Jahrestagung der Deutschen Gesellschaft f{\"u}r Biofeedback e. V., Regensburg, 2018}, booktitle = {Jahrestagung der Deutschen Gesellschaft f{\"u}r Biofeedback e. V., Regensburg, 2018}, language = {de} } @inproceedings{SuessKubowitschRasmussenetal., author = {S{\"u}ß, Franz and Kubowitsch, Simone and Rasmussen, John and Verkerke, Gijsbertus Jacob and Dendorfer, Sebastian}, title = {The influence of cognitive stress on muscle activation and spinal disc load}, series = {European Society of Biomechanics meeting 2019, Vienna, Austria}, booktitle = {European Society of Biomechanics meeting 2019, Vienna, Austria}, language = {en} } @inproceedings{MelznerEngelhardtHavelkovaetal., author = {Melzner, Maximilian and Engelhardt, Lucas and Havelkova, Leonard and Simon, Ulrich and Dendorfer, Sebastian}, title = {A new musculoskeletal AnyBody detailed hand model validated by electromyography}, series = {16th International Symposium on Computer Methods in Biomechanics and Biomedical Engineering (CMBBE) 2019, New York City, USA}, booktitle = {16th International Symposium on Computer Methods in Biomechanics and Biomedical Engineering (CMBBE) 2019, New York City, USA}, abstract = {The AnyBody™ Modeling System (AMS) [1], is an universally used musculoskeletal simulation software using inverse dynamics. Until now, no complete human hand model is known in the AMS. Also considering other musculoskeletal software platforms, just one detailed entire hand model is recently published [2] but is only based on one subject. The aim of this work is to implement a full detailed hand model for the AMS including all extrinsic and intrinsic muscles using data by the UWB gained through an anatomical study of ten cadaver hands.}, language = {en} } @inproceedings{WulfLindnerStrahringeretal., author = {Wulf, Frederik and Lindner, Tobias and Strahringer, Susanne and Westner, Markus}, title = {IaaS, PaaS, or SaaS? The Why of Cloud Computing Delivery Model Selection}, series = {Proceedings of the 54th Hawaii International Conference on System Sciences, 2021}, booktitle = {Proceedings of the 54th Hawaii International Conference on System Sciences, 2021}, isbn = {978-0-9981331-4-0}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-7913}, pages = {6285 -- 6294}, abstract = {Most large-scale organizations adopted Cloud Computing (CC) on a company level in recent years. Managers now face the challenge to appropriately implement CC "operationally", i.e., for information systems (ISs). We refer to this as post-adoption, addressing the extent of technology usage after adoption. Specifically, managers need to choose among the CC delivery models Infrastructure-as-a-Service (IaaS), Platform-as-a-Service (PaaS), and Software-asa-Service (SaaS). We differentiate the determinants of this post-adoption decision for IaaS, PaaS, and SaaS. Based on this analysis, we derive criteria that guide managers' delivery model selection: Adopt 1) IaaS for ISs requiring flexibility and reduced time to market, 2) PaaS to access specialized resources, and 3) SaaS to focus on core competencies. Moreover, we analyze the impact on the CC strategy and postulate them as recommendations: I) acknowledge the interplay between governance and time-to-market, II) realize cost savings on company level, and III) consider strategically important ISs for CC.}, language = {en} } @inproceedings{Dendorfer, author = {Dendorfer, Sebastian}, title = {Biomechanical evaluation and optimisation of countermeasure exercises}, series = {ESA/ESTEC Bedrest Strategy Workshop, Noordwijk, NL, 2009}, booktitle = {ESA/ESTEC Bedrest Strategy Workshop, Noordwijk, NL, 2009}, language = {en} } @inproceedings{Dendorfer, author = {Dendorfer, Sebastian}, title = {How much iron to pump? The determination of muscle forces for activities of daily living}, series = {DGU, Berlin, 2008}, booktitle = {DGU, Berlin, 2008}, language = {en} } @inproceedings{HammerDendorfer, author = {Hammer, Joachim and Dendorfer, Sebastian}, title = {Cyclic loading and microstructure of cancellous bone}, series = {Journal of Biomechanics}, volume = {41}, booktitle = {Journal of Biomechanics}, number = {Suppl. 1, July 2008}, doi = {10.1016/S0021-9290(08)70409-3}, pages = {S410}, language = {en} } @inproceedings{DendorferKubowitsch, author = {Dendorfer, Sebastian and Kubowitsch, Simone}, title = {The interaction of mental stress and biomechanics}, series = {Health Technology Triangle, Weiden, 2016}, booktitle = {Health Technology Triangle, Weiden, 2016}, language = {en} } @inproceedings{AuerKubowitschKrutschetal., author = {Auer, Simon and Kubowitsch, Simone and Krutsch, Werner and Renkawitz, Tobias and S{\"u}ß, Franz and Dendorfer, Sebastian}, title = {Effect of mental demand on knee forces in professional youth soccer players}, series = {ISBS Proceedings Archive}, volume = {38}, booktitle = {ISBS Proceedings Archive}, number = {1, Art. 28}, abstract = {Soccer is one of the most popular sports all around the world. It is an injurious type of sport with a focus on lower extremities and high psychological pressure during matches. The stressor is linked with injuries and an increased musculoskeletal loading. This study investigates the influence of cognitive stress on the load profile of the knee joint. Twelve professional youth soccer players performed highly dynamic runs with and without additional cognitive stress. The runs were analysed with a musculoskeletal simulation software. The data analysis shows no difference in knee joint reaction loading under additional mental stress compared to the baseline. Yet running times are significantly lower in the baseline. While there is no increase in the joint loads, the running times indicate an altered movement behaviour when the subjects are exposed to additional mental demand.}, subject = {Kniegelenk}, language = {en} } @inproceedings{Herrmann, author = {Herrmann, Frank}, title = {Evaluierung von Standardsoftware zur Abbildung von Gesch{\"a}ftsprozessen}, series = {Herausforderungen an die Wirtschaftsinformatik: Wissensmanagement, E-Business und ereignisgesteuerte Gesch{\"a}ftsprozesse in Echtzeit}, booktitle = {Herausforderungen an die Wirtschaftsinformatik: Wissensmanagement, E-Business und ereignisgesteuerte Gesch{\"a}ftsprozesse in Echtzeit}, editor = {Fuchs, Gerhard and M{\"u}ller, Christian and Ritz, Harald and Saint-Mont, Uwe}, publisher = {Verlag News \& Media}, address = {Berlin}, doi = {10.15771/978-3-936527-10-0}, pages = {52 -- 69}, language = {de} } @inproceedings{WeberDrueeke, author = {Weber, Karsten and Dr{\"u}eke, Ricarda}, title = {Privacy, personal data protection, and the need to differentiate}, series = {Ethics of New Information Technology. Proceedings of the 6th International Conference of Computer Ethics: Philosophical Enquiries (CEPE2005)}, booktitle = {Ethics of New Information Technology. Proceedings of the 6th International Conference of Computer Ethics: Philosophical Enquiries (CEPE2005)}, editor = {Brey, Philip and Grodzinsky, F. and Introna, L.}, pages = {13}, abstract = {The coming years will be characterized by the development of mobile ICT that will enable con - sumers to use information and communication services everywhere and anytime. Technologies like GPRS, WLAN, or UMTS can be used stand-alone or in combination with other technologies like RFID or GPS to provide, for instance, location-aware services. Mobile ICT is to be expected to evolve to that what often is called Ambient Intelligence, Ubiquitous or Pervasive Computing. It is likely that such new technologies will affect personnel privacy because providing mobile ICT services inherits the identification and often the exact localization of users. In the following text we shall analyze possible threats of privacy. We will distinguish different dimensions or aspects of privacy to show how new technologies can affect them. After that, we shall argue that it is necessary to make a distinction of privacy and data protection: privacy primarily is a matter of social norms and data protection the realm of technical measurements. Additionally, we will provide some empirical evidence that users of the Internet make that distinction. Finally, we will claim that the right to privacy and privacy itself only can be protected if there are widely accepted social norms regarding privacy.}, language = {en} } @inproceedings{Weber, author = {Weber, Karsten}, title = {Computersimulationen im Entdeckungszusammenhang}, series = {Kreativit{\"a}t. Proceedings des XX. Deutschen Kongresses f{\"u}r Philosophie}, booktitle = {Kreativit{\"a}t. Proceedings des XX. Deutschen Kongresses f{\"u}r Philosophie}, editor = {Abel, G.}, publisher = {Universit{\"a}tsverlag der TU Berlin}, address = {Berlin}, pages = {8}, language = {de} } @inproceedings{Weber, author = {Weber, Karsten}, title = {Die andere Seite der Verteilungsgerechtigkeit}, series = {Philosophische Perspektiven. Beitr{\"a}ge zum VII. {\"O}sterreichischen Kongress f{\"u}r Philosophie}, booktitle = {Philosophische Perspektiven. Beitr{\"a}ge zum VII. {\"O}sterreichischen Kongress f{\"u}r Philosophie}, editor = {Neumaier, O. and Sedmak, Clemens and Zichy, M.}, publisher = {Ontos}, address = {Lancaster}, pages = {5}, language = {de} } @inproceedings{DrueekeHaugKelleretal., author = {Dr{\"u}eke, Ricarda and Haug, Sonja and Keller, Werner and Weber, Karsten}, title = {Verhalten und Einstellungen zum Mobiltelefonieren}, series = {Informatik 2007 - Informatik trifft Logistik, Band 1 der Proceedings zur 37. Jahrestagung der Gesellschaft f{\"u}r Informatik e.V. (GI); 24.-27. September 2007 in Bremen}, booktitle = {Informatik 2007 - Informatik trifft Logistik, Band 1 der Proceedings zur 37. Jahrestagung der Gesellschaft f{\"u}r Informatik e.V. (GI); 24.-27. September 2007 in Bremen}, editor = {Koschke, Rainer}, publisher = {Gesellschaft f{\"u}r Informatik e. V.}, address = {Bonn}, isbn = {978-3-88579-203-1}, pages = {354 -- 358}, language = {de} } @inproceedings{NagenborgWeber, author = {Nagenborg, Michael and Weber, Karsten}, title = {Ubiquitous Computing, Pervasive Computing, Ambient Intelligence ... Surveillance and Control?}, series = {Informatik 2007 - Informatik trifft Logistik, Band 1 der Proceedings zur 37. Jahrestagung der Gesellschaft f{\"u}r Informatik e.V. (GI); 24.-27. September 2007 in Bremen}, booktitle = {Informatik 2007 - Informatik trifft Logistik, Band 1 der Proceedings zur 37. Jahrestagung der Gesellschaft f{\"u}r Informatik e.V. (GI); 24.-27. September 2007 in Bremen}, editor = {Koschke, Rainer}, publisher = {Gesellschaft f{\"u}r Informatik e.V.}, address = {Bonn}, isbn = {978-3-88579-203-1}, pages = {329 -- 333}, language = {en} } @inproceedings{Weber, author = {Weber, Karsten}, title = {Ubiquit{\"a}re Informations- und Kommunikationstechnologie}, series = {Der Systemblick auf Innovation - Technikfolgenabsch{\"a}tzung in der Technikgestaltung}, booktitle = {Der Systemblick auf Innovation - Technikfolgenabsch{\"a}tzung in der Technikgestaltung}, editor = {Decker, Michael and Grunwald, Armin and Knapp, Martin}, publisher = {Edition Sigma}, address = {Berlin}, pages = {319 -- 326}, language = {de} } @inproceedings{Weber, author = {Weber, Karsten}, title = {Informationsnachhaltigkeit. Vom schwierigen Umgang mit Informationsg{\"u}tern}, series = {Wissen - Wissenschaft - Organisation. Proceedings der 12. Tagung der Deutschen Sektion der Internationalen Gesellschaft f{\"u}r Wissensorganisation ; Bonn, 19. bis 21. Oktober 2009}, booktitle = {Wissen - Wissenschaft - Organisation. Proceedings der 12. Tagung der Deutschen Sektion der Internationalen Gesellschaft f{\"u}r Wissensorganisation ; Bonn, 19. bis 21. Oktober 2009}, editor = {Ohly, Heinz Peter}, publisher = {Ergon}, address = {W{\"u}rzburg}, pages = {19 -- 31}, language = {de} } @inproceedings{Weber, author = {Weber, Karsten}, title = {Wer bestimmt {\"u}ber den Tod? Interventionsrechtete von Familienangeh{\"o}rigen und anderen Personen}, series = {Familie versus Patientenautonomie? Zur Rolle der Familie bei Behandlungsentscheidungen ; Tagungsband der Taunus Winter School}, booktitle = {Familie versus Patientenautonomie? Zur Rolle der Familie bei Behandlungsentscheidungen ; Tagungsband der Taunus Winter School}, editor = {Roth{\"a}rmel, Sonja and Schmidt, K.W. and Wolfslast, G.}, publisher = {Haag + Herchen}, address = {Frankfurt am Main}, isbn = {978-3-89846-436-9}, language = {de} } @inproceedings{MendelSouzaJrRauberetal., author = {Mendel, Robert and Souza Jr., Luis Antonio de and Rauber, David and Papa, Jo{\~a}o Paulo and Palm, Christoph}, title = {Semi-supervised Segmentation Based on Error-Correcting Supervision}, series = {Computer vision - ECCV 2020: 16th European conference, Glasgow, UK, August 23-28, 2020, Proceedings, Part XXIX}, booktitle = {Computer vision - ECCV 2020: 16th European conference, Glasgow, UK, August 23-28, 2020, Proceedings, Part XXIX}, publisher = {Springer}, address = {Cham}, isbn = {978-3-030-58525-9}, doi = {10.1007/978-3-030-58526-6_9}, pages = {141 -- 157}, abstract = {Pixel-level classification is an essential part of computer vision. For learning from labeled data, many powerful deep learning models have been developed recently. In this work, we augment such supervised segmentation models by allowing them to learn from unlabeled data. Our semi-supervised approach, termed Error-Correcting Supervision, leverages a collaborative strategy. Apart from the supervised training on the labeled data, the segmentation network is judged by an additional network. The secondary correction network learns on the labeled data to optimally spot correct predictions, as well as to amend incorrect ones. As auxiliary regularization term, the corrector directly influences the supervised training of the segmentation network. On unlabeled data, the output of the correction network is essential to create a proxy for the unknown truth. The corrector's output is combined with the segmentation network's prediction to form the new target. We propose a loss function that incorporates both the pseudo-labels as well as the predictive certainty of the correction network. Our approach can easily be added to supervised segmentation models. We show consistent improvements over a supervised baseline on experiments on both the Pascal VOC 2012 and the Cityscapes datasets with varying amounts of labeled data.}, subject = {Semi-Supervised Learning}, language = {en} } @inproceedings{BrosigWestnerStrahringer, author = {Brosig, Christoph and Westner, Markus and Strahringer, Susanne}, title = {Revisiting the Concept of IT Capabilities in the Era of Digitalization}, series = {2020 IEEE 22nd Conference on Business Informatics (CBI 2020): Antwerp, Belgium, 22-24 June 2020, proceedings}, booktitle = {2020 IEEE 22nd Conference on Business Informatics (CBI 2020): Antwerp, Belgium, 22-24 June 2020, proceedings}, publisher = {IEEE}, doi = {10.1109/CBI49978.2020.00017}, pages = {84 -- 93}, abstract = {In the era of digitalization, companies review how to build competitive advantage drawing on their capabilities. In this context, the paper revisits the concept of IT capabilities. We summarize the "canonical" body of literature to characterize how leading scholars conceptualized and differentiated IT capabilities and then we show how new types of IT capabilities (for example, rising from SMACIT technologies) relate to this. We find that the resource-based view is still leading in how to conceptualize IT capabilities. However, an alternative perspective on IT assets is emerging, looking at it from the angle of digital technologies as stacks. Digital technologies form the foundation for a new technology-driven perspective on IT capabilities. This new view complements the established differentiation of IT capabilities considering IT infrastructure flexibility, IT management, and IT personnel capability. Both perspectives describe the explorative and exploitative nature of IT capabilities. This paper helps scholars and practitioners to clearly distinguish different perspectives of IT capabilities on how to build a competitive advantage from IT today.}, subject = {Informationstechnik}, language = {en} } @inproceedings{WeberWackerbarth, author = {Weber, Karsten and Wackerbarth, Alena}, title = {Partizipative Gestaltung verl{\"a}sslicher Assistenzsysteme f{\"u}r die Pflege alter und hochbetagter Menschen}, series = {Informatik'2015: 45. Jahrestagung der Gesellschaft f{\"u}r Informatik, Informatik, Energie und Umwelt, Tagung von 28. September - 2. Oktober 2015 in Cottbus}, booktitle = {Informatik'2015: 45. Jahrestagung der Gesellschaft f{\"u}r Informatik, Informatik, Energie und Umwelt, Tagung von 28. September - 2. Oktober 2015 in Cottbus}, editor = {Hofstedt, Petra and Meer, Klaus and Schmitt, Ingo}, publisher = {Gesellschaft f{\"u}r Informatik}, address = {Bonn}, pages = {1247 -- 1249}, abstract = {Ambient Assisted Living- (AAL) bzw. altersgerechte Assistenzsysteme sollen in der Pflege alter und hochbetagter Menschen, aber auch anderer physisch oder psychisch gehandicapter Personen, eingesetzt werden. Daf{\"u}r m{\"u}ssen diese Systeme hochverl{\"a}sslich sein, aber gleichzeitig auch Erwartungen erf{\"u}llen, die weniger im technischen und st{\"a}rker im sozialen Bereich angesiedelt sind. Nach einer kurzen Einf{\"u}hrung der Geschichte dieser Systeme und der Beschreibung des Stands der Technik soll auf verschiedene Evaluationswerkzeuge eingegangen werden, die dazu genutzt werden k{\"o}nnen, eine partizipative Technikgestaltung von AAL-Systemen zu unterst{\"u}tzen}, language = {de} } @inproceedings{Fuhrmann, author = {Fuhrmann, Thomas}, title = {Let the students publish}, series = {IEEE International Conference on Teaching, Assessment and Learning for Engineering (TALE), 26-29 August 2013, Bali Dynasty Resort, Kuta, Indonesia}, booktitle = {IEEE International Conference on Teaching, Assessment and Learning for Engineering (TALE), 26-29 August 2013, Bali Dynasty Resort, Kuta, Indonesia}, publisher = {IEEE}, isbn = {978-1-4673-6355-6}, doi = {10.1109/TALE.2013.6654515}, abstract = {In technical study programs on the bachelor level the focus is mainly directed on the scientific education in theory and practice. Publication is usually started during the PhD phase when students write their first scientific papers. During the last years some very successful projects were made at the university of applied sciences Regensburg to motivate bachelor students doing their first own small publications. The results of these projects are presented in this paper and ideas how students can publish are given.}, language = {en} } @inproceedings{AltenbuchnerWeberFuchs, author = {Altenbuchner, Amelie and Weber, Karsten and Fuchs, Dominik}, title = {N{\"u}tzlichkeit und Nutzung}, series = {Assistive Technik f{\"u}r selbstbestimmtes Wohnen, 6. Ambient Medicine® Forum 19.-20. Februar 2019}, booktitle = {Assistive Technik f{\"u}r selbstbestimmtes Wohnen, 6. Ambient Medicine® Forum 19.-20. Februar 2019}, editor = {Friedrich, Petra and Fuchs, Dominik}, publisher = {Cuvillier}, address = {G{\"o}ttingen}, pages = {149 -- 156}, subject = {AAL-Technik}, language = {de} } @inproceedings{WeberScornaHaug, author = {Weber, Karsten and Scorna, Ulrike and Haug, Sonja}, title = {ELSI in Serious Games f{\"u}r die technikunterst{\"u}tzte medizinische Ausbildung: das Beispiel HaptiVisT}, series = {3. Transdisziplin{\"a}re Konferenz "Technische Unterst{\"u}tzungssysteme, die die Menschen wirklich wollen", 11.-12.12.2018, Hamburg}, booktitle = {3. Transdisziplin{\"a}re Konferenz "Technische Unterst{\"u}tzungssysteme, die die Menschen wirklich wollen", 11.-12.12.2018, Hamburg}, editor = {Weidner, Robert and Karafillidis, Athanasios}, publisher = {Helmut-Schmidt-Universit{\"a}t}, address = {Hamburg}, isbn = {978-3-86818-245-3}, pages = {187 -- 194}, abstract = {Das haptisch-visuelle Trainingssystem HaptiVisT zur Unterst{\"u}tzung der chirurgischen Ausbildung f{\"u}r zwei chirurgische Anwendungsfelder (Cochlea-Implantationen und minimalinvasive Handchirurgie) im Rahmen eines Serious Games ber{\"u}hrt zentrale medizinethische Prinzipien (Autonomie, Nichtschaden, Wohltun, Gerechtigkeit) sowie rechtliche und soziale Fragen. Bei der Entwicklung ist von Projektbeginn an eine Begleitforschung zu ethischen, rechtlichen und sozialen Implikationen (ELSI) vorgesehen, deren Methodik und erste Ergebnisse vorgestellt werden. Die Ergebnisse st{\"u}tzen sich auf eine empirisch basierte Anforderungsanalyse aus Anwender- und Entwicklersicht.}, subject = {Unterst{\"u}tzungstechnologie}, language = {de} } @inproceedings{KlotzWestnerStrahringer, author = {Klotz, Stefan and Westner, Markus and Strahringer, Susanne}, title = {From Shadow IT to Business-managed IT and Back Again}, series = {Pacific Asia Conference on Information Systems (PACIS): 2020, Dubai}, booktitle = {Pacific Asia Conference on Information Systems (PACIS): 2020, Dubai}, pages = {14}, abstract = {Today, information technology (IT) is not anymore solely deployed and maintained by the IT organization, but also by business units. IT deployed or managed by business units is called Shadow IT (without alignment with the IT organization) or Business-managed IT (in alignment or a split responsibility model with the IT organization), contrasting "classical" IT. However, the responsibility for deployed IT might change over time. Therefore, this paper conceptualizes the progression of the responsibility for IT as a trajectory through initialization, potential transitions, and discontinuance. The paper illustrates this conceptual framework using four exemplary case vignettes of IT instances. Empirical findings of the case vignettes determine indications when employees initialize an IT instance as Shadow IT, Business-managed IT, or IT-managed systems and reasons why the responsibility for an IT instance changes over time. The results suggest that scholars and practitioners should add a temporal dimension to the governance of IT instances.}, subject = {IT-Governance}, language = {en} } @inproceedings{PalmSchollLehmannetal., author = {Palm, Christoph and Scholl, Ingrid and Lehmann, Thomas M. and Spitzer, Klaus}, title = {Trennung von diffuser und spiegelnder Reflexion in Farbbildern des Larynx zur Untersuchung von Farb- und Formmerkmalen der Stimmlippen}, series = {Bildverarbeitung f{\"u}r die Medizin. Algorithmen, Systeme, Anwendungen. Proceedings des Aachener Workshops am 8. und 9. November 1996}, booktitle = {Bildverarbeitung f{\"u}r die Medizin. Algorithmen, Systeme, Anwendungen. Proceedings des Aachener Workshops am 8. und 9. November 1996}, editor = {Lehmann, Thomas M. and Scholl, Ingrid and Spitzer, Klaus}, publisher = {Verlag der Augustinus-Buchhandlung}, address = {Aachen}, pages = {229 -- 234}, abstract = {Zur diagnostischen Unterst{\"u}tzung bei der Befundung laryngealer Erkrankungen soll eine Farb- und Formanalyse der Stimmlippen durchgef{\"u}hrt werden. In diesem Beitrag wird ein Verfahren zur Trennung der spiegelnden und diffusen Reflexionsanteile in Farbbildern des Larynx vorgestellt. Die Farbe der diffusen Komponente entspricht dabei der beleuchtungsunabh{\"a}ngigen Objektfarbe, w{\"a}hrend deren Wichtungsfaktoren als Eingabe f{\"u}r Shape-from-Shading-Verfahren zur Oberfl{\"a}chenrekonstruktion dienen.}, subject = {Laryngoskopie}, language = {de} } @inproceedings{HassanIlgnerPalmetal., author = {Hassan, H. and Ilgner, Justus F. R. and Palm, Christoph and Lehmann, Thomas M. and Spitzer, Klaus and Westhofen, Martin}, title = {Objective Judgement of Endoscopic Laryngeal Images}, series = {Advances in Quantitative Laryngoscopy, Voice and Speech Research, Proceedings of the 3rd International Workshop, RWTH Aachen}, booktitle = {Advances in Quantitative Laryngoscopy, Voice and Speech Research, Proceedings of the 3rd International Workshop, RWTH Aachen}, editor = {Lehmann, Thomas M. and Spitzer, Klaus and Tolxdorff, Thomas}, pages = {135 -- 142}, abstract = {Video Documentation of endoscopic findings simplifies diagnostic counseling of the patient and aids pre-operative discussion among the medical team. Judgment of such images is still subjective and can not give a quantitative evaluation of the disease process regarding diagnosis or response to treatment. Modern treatment of early laryngeal cancer with laserablation requires intensive follow up and frequent direct laryngoscopy under general anesthesia with blind biopsies to detect any tumor residual or recurrence. Inflammatory conditions of the larynx are frequently confused with other causes of dysphonia. Mapping anddigital analysis of the documented image will suggest the tumor site and avoids undue blind biopsies under anesthesia. However, varying illumination results in different colors reflected from the same object. To achieve quantitative analysis, color constancy has to be assured. Inthis paper, the environment is presented which allow the objective judgment of larngoscopies.}, language = {en} } @inproceedings{SchollPalmSovakaretal., author = {Scholl, Ingrid and Palm, Christoph and Sovakar, Abhijit and Lehmann, Thomas M. and Spitzer, Klaus}, title = {Quantitative Analyse der Stimmlippen}, series = {5. Workshop Digitale Bildverarbeitung in der Medizin, Universit{\"a}t Freiburg, 10.-11. M{\"a}rz 1997}, booktitle = {5. Workshop Digitale Bildverarbeitung in der Medizin, Universit{\"a}t Freiburg, 10.-11. M{\"a}rz 1997}, editor = {Arnolds, B. and Mueller, H. and Saupe, D. and Tolxdorff, Thomas}, pages = {81 -- 86}, language = {de} } @inproceedings{PalmSchollLehmannetal., author = {Palm, Christoph and Scholl, Ingrid and Lehmann, Thomas M. and Spitzer, Klaus}, title = {Quantitative Farbmessung in laryngoskopischen Bildern}, series = {Bildverarbeitung f{\"u}r die Medizin}, booktitle = {Bildverarbeitung f{\"u}r die Medizin}, editor = {Lehmann, Thomas M. and Metzler, V. and Spitzer, Klaus and Tolxdorff, Thomas}, publisher = {Springer}, address = {Berlin}, doi = {10.1007/978-3-642-58775-7_81}, pages = {412 -- 416}, abstract = {Quantitative Farbmessungen sollen die Diagnostik laryngealer Erkrankungen unterst{\"u}tzen. Dabei wird der Farbeindruck nicht nur durch die Reflexionseigenschaften des Gewebes sondern auch durch die Farbe der verwendeten Lichtquelle beeinflußt. Der hier vorgestellte Farbkonstanz-Algorithmus basiert auf dem dichromatischen Reflexionsmodell und liefert eine pixelweise Trennung des Farbbildes in seine beiden Faxbanteile. Die K{\"o}rperfarbe entspricht dabei der gewebespezifischen Reflexion, die Oberf{\"a}chenfarbe der Strahlung der Lichtquelle.}, language = {de} } @inproceedings{PalmSchollLehmannetal., author = {Palm, Christoph and Scholl, Ingrid and Lehmann, Thomas M. and Spitzer, Klaus}, title = {Nutzung eines Farbkonstanz-Algorithmus zur Entfernung von Glanzlichtern in laryngoskopischen Bildern}, series = {Methoden der Medizinischen Informatik, Biometrie und Epidemiologie in der modernen Informationsgesellschaft}, booktitle = {Methoden der Medizinischen Informatik, Biometrie und Epidemiologie in der modernen Informationsgesellschaft}, editor = {Greiser, E. and Wischnewsky, M.}, publisher = {MMV Medien und Medizin}, address = {M{\"u}nchen}, isbn = {9783820813357}, pages = {300 -- 303}, abstract = {1 Einf{\"u}hrung Funktionelle und organische St{\"o}rungen im Larynx beeintr{\"a}chtigen die Ausdrucksf{\"a}higkeit des Menschen. Zur Diagnostik und Verlaufkontrolle werden die Stimmlippen im Larynx mit Hilfe der Video-Laryngoskopie aufgenommen. Zur optimalen Farbmessung wird dazu an das Lupenendoskop eine 3-Chip-CCD-Kamera angeschlossen, die eine unabh{\"a}ngige Aufnahme der drei Farbkan{\"a}le erlaubt. Die bisherige subjektive Befundung ist von der Erfahrung des Untersuchers abh{\"a}ngig und l{\"a}ßt nur eine grobe Klassifikation der Krankheitsbilder zu. Zur Objektivierung werden daher quantitative Parameter f{\"u}r Farbe, Textur und Schwingung entwickelt. Neben dem Einfluß der wechselnden Lichtquellenfarbe auf den Farbeindruck ist die Sekretauflage auf den Stimmlippen ein Problem bei der Farb-und Texturanalyse. Sie kann zu ausgedehnten Glanzlichtern f{\"u}hren und so weite Bereiche der Stimmlippen f{\"u}r die Farb-und Texturanalyse unbrauchbar machen. Dieser Beitrag stellt einen Farbkonstanz-Algorithmus vor, der unabh{\"a}ngig von der Lichtquelle quantitative Farbwerte des Gewebes liefert und die Glanzlichtdetektion und -elimination erm{\"o}glicht. 2 Methodik Ziel des Farbkonstanz-Algorithmus ist die Trennung von Lichtquellen-und Gewebefarbe. Unter Verwendung des dichromatischen Reflexionsmodells [1] kann die Oberfl{\"a}chenreflexion mit der Farbe der Lichtquelle und die K{\"o}rperreflexion mit der Gewebefarbe identifiziert werden. Der Farbeindruck entsteht aus der Linearkombination beider Farbkomponenten. Ihre Gewichtung ist von der Aufnahmegeometrie abh{\"a}ngig, insbesondere vom Winkel zwischen Oberfl{\"a}chennormalen und dem Positionsvektor der Lichtquelle. In einem zweistufigen Verfahren wird zun{\"a}chst die Lichtquellenfarbe gesch{\"a}tzt, dann die Gewebefarbe ermittelt. Hieraus k{\"o}nnen beide Farbanteile durch die Berechnung der Gewichtsfaktoren pixelweise getrennt werden.}, language = {de} } @inproceedings{PalmPelkmannLehmannetal., author = {Palm, Christoph and Pelkmann, Annegret and Lehmann, Thomas M. and Spitzer, Klaus}, title = {Distortion Correction of Laryngoscopic Images}, series = {Advances in quantitative laryngoscopy, voice and speech research, Proceedings of the 3rd international workshop Aachen, RWTH}, booktitle = {Advances in quantitative laryngoscopy, voice and speech research, Proceedings of the 3rd international workshop Aachen, RWTH}, pages = {117 -- 125}, abstract = {Laryngoscopic images of the vocal tract are used for diagnostic purposes. Quantitative mea-surements like changes of the glottis size or the surface of the vocal cords during an image sequence can be helpful to describe the healing process or to compare the findings of diffe-rent patients. Typically the endoscopic images are circulary symmetric distorted (barrel di-stortion). Therefore measurements of geometric dimensions depend on the object´s position in the image. In this paper an algorithm is presented which allows the computation of the translational invariant "real" object size by correcting the image distortion without using additional calibration of the optical environment.}, language = {en} }