TY - CHAP A1 - Kubowitsch, Simone A1 - Süß, Franz A1 - Jansen, Petra A1 - Dendorfer, Sebastian T1 - Muscular imbalances during experimentally induced stress T2 - 23th Congress of the European Society of Biomechanics, Sevilla, Spain, 2017 Y1 - 2017 ER - TY - CHAP A1 - Süß, Franz A1 - Kubowitsch, Simone A1 - Verkerke, Gijsbertus Jacob A1 - Dendorfer, Sebastian T1 - The influence of mental stress on spinal disc loading and muscle activity T2 - 23th Congress of the European Society of Biomechanics, Sevilla, Spain, 2017 Y1 - 2017 ER - TY - CHAP A1 - Gross, Simon A1 - Verkerke, Gijsbertus Jacob A1 - Dendorfer, Sebastian T1 - Investigation of external load dependent static and dynamic muscle fatigue T2 - 23th Congress of the European Society of Biomechanics, Sevilla, Spain, 2017 Y1 - 2017 ER - TY - CHAP A1 - Pilling, A. A1 - Süß, Franz A1 - Kubowitsch, Simone A1 - Dendorfer, Sebastian T1 - Experimental workflow for determining psychological stress from physiological biosignals T2 - Jahrestagung der BIOMEDIZINISCHEN TECHNIK und Dreiländertagung der MEDIZINISCHEN PHYSIK, Dresden, Germany, 2017 Y1 - 2017 ER - TY - CHAP A1 - Jungtäubl, Dominik A1 - Aurbach, Maximilian A1 - Melzner, Maximilian A1 - Spicka, Jan A1 - Süß, Franz A1 - Dendorfer, Sebastian T1 - EMG-Based Validation of Musculoskeletal Models Considering Crosstalk T2 - International Conference BIOMDLORE, June 28 - 30 2018, Białystok, Poland N2 - 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. KW - musculoskeletal modeling KW - validation KW - surface electromyography KW - crosstalk Y1 - 2018 U6 - https://doi.org/10.1109/BIOMDLORE.2018.8467211 ER - TY - CHAP A1 - Kubowitsch, Simone A1 - Süß, Franz A1 - Jansen, Petra A1 - Dendorfer, Sebastian T1 - Comparison of dynamic muscular imbalances in back pain patients and healthy controls T2 - World Congress Biomechanics Dublin, 2018 Y1 - 2018 ER - TY - CHAP A1 - Gross, Simon A1 - Verkerke, Gijsbertus Jacob A1 - Dendorfer, Sebastian T1 - Combined Experimental and Numerical Approach to Investigate Changes in Muscle Recruitment Pattern of the Back Muscles during Exhausting Exercise T2 - World Congress Biomechanics Dublin, 2018 N2 - 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. Y1 - 2018 ER - TY - CHAP A1 - Seefried, C. A1 - Aurbach, Maximilian A1 - Wyss, C. A1 - Dendorfer, Sebastian T1 - Achilles tendon lengthening alters stresses in the growth plate T2 - International Conference BIOMDLORE, June 28 - 30 2018, Białystok, Poland Y1 - 2018 ER - TY - CHAP A1 - Süß, Franz A1 - Kubowitsch, Simone A1 - Verkerke, Gijsbertus Jacob A1 - Dendorfer, Sebastian T1 - Investigation of cognitive stress induced changes in spinal disc forces due to altered kinematics and muscle activity T2 - World Congress Biomechanics, Dublin, 2018 Y1 - 2018 ER - TY - CHAP A1 - Kubowitsch, Simone A1 - Dendorfer, Sebastian T1 - Psychologie und Biomechanik – Integrierte Betrachtung von Muskelrekrutierung BT - Erkenntnisse und Ableitungen für Biofeedback T2 - Jahrestagung der Deutschen Gesellschaft für Biofeedback e. V., Regensburg, 2018 Y1 - 2018 ER - TY - CHAP A1 - Süß, Franz A1 - Kubowitsch, Simone A1 - Rasmussen, John A1 - Verkerke, Gijsbertus Jacob A1 - Dendorfer, Sebastian T1 - The influence of cognitive stress on muscle activation and spinal disc load T2 - European Society of Biomechanics meeting 2019, Vienna, Austria Y1 - 2019 UR - https://owncloud.tuwien.ac.at/index.php/s/dovqqcj02VeZHze ER - TY - CHAP A1 - Melzner, Maximilian A1 - Engelhardt, Lucas A1 - Havelkova, Leonard A1 - Simon, Ulrich A1 - Dendorfer, Sebastian T1 - A new musculoskeletal AnyBody detailed hand model validated by electromyography T2 - 16th International Symposium on Computer Methods in Biomechanics and Biomedical Engineering (CMBBE) 2019, New York City, USA N2 - 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. Y1 - 2019 UR - https://www.researchgate.net/publication/336944957_A_NEW_MUSCULOSKELETAL_ANYBODY_DETAILED_HAND_MODEL_VALIDATED_BY_ELECTROMYOGRAPHY ER - TY - CHAP A1 - Wulf, Frederik A1 - Lindner, Tobias A1 - Strahringer, Susanne A1 - Westner, Markus T1 - IaaS, PaaS, or SaaS? The Why of Cloud Computing Delivery Model Selection BT - Vignettes on the Post-Adoption of Cloud Computing T2 - Proceedings of the 54th Hawaii International Conference on System Sciences, 2021 N2 - 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. KW - Cloud Computing KW - IT Sourcing Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-7913 UR - https://aisel.aisnet.org/hicss-54/os/practice-based_research/5/ SN - 978-0-9981331-4-0 SP - 6285 EP - 6294 ER - TY - CHAP A1 - Dendorfer, Sebastian T1 - Biomechanical evaluation and optimisation of countermeasure exercises T2 - ESA/ESTEC Bedrest Strategy Workshop, Noordwijk, NL, 2009 Y1 - 2009 ER - TY - CHAP A1 - Dendorfer, Sebastian T1 - How much iron to pump? The determination of muscle forces for activities of daily living T2 - DGU, Berlin, 2008 Y1 - 2008 ER - TY - CHAP A1 - Hammer, Joachim A1 - Dendorfer, Sebastian T1 - Cyclic loading and microstructure of cancellous bone T2 - Journal of Biomechanics Y1 - 2008 U6 - https://doi.org/10.1016/S0021-9290(08)70409-3 VL - 41 IS - Suppl. 1, July 2008 SP - S410 ER - TY - CHAP A1 - Dendorfer, Sebastian A1 - Kubowitsch, Simone T1 - The interaction of mental stress and biomechanics T2 - Health Technology Triangle, Weiden, 2016 Y1 - 2016 ER - TY - CHAP A1 - Auer, Simon A1 - Kubowitsch, Simone A1 - Krutsch, Werner A1 - Renkawitz, Tobias A1 - Süß, Franz A1 - Dendorfer, Sebastian T1 - Effect of mental demand on knee forces in professional youth soccer players T2 - ISBS Proceedings Archive N2 - 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. KW - Kniegelenk KW - Körperliche Belastung KW - Stress KW - Computersimulation Y1 - 2020 UR - https://commons.nmu.edu/isbs/vol38/iss1/28 VL - 38 IS - 1, Art. 28 ER - TY - CHAP A1 - Herrmann, Frank ED - Fuchs, Gerhard ED - Müller, Christian ED - Ritz, Harald ED - Saint-Mont, Uwe T1 - Evaluierung von Standardsoftware zur Abbildung von Geschäftsprozessen T2 - Herausforderungen an die Wirtschaftsinformatik: Wissensmanagement, E-Business und ereignisgesteuerte Geschäftsprozesse in Echtzeit Y1 - 2007 U6 - https://doi.org/10.15771/978-3-936527-10-0 SP - 52 EP - 69 PB - Verlag News & Media CY - Berlin ER - TY - CHAP A1 - Weber, Karsten A1 - Drüeke, Ricarda ED - Brey, Philip ED - Grodzinsky, F. ED - Introna, L. T1 - Privacy, personal data protection, and the need to differentiate T2 - Ethics of New Information Technology. Proceedings of the 6th International Conference of Computer Ethics: Philosophical Enquiries (CEPE2005) N2 - 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. KW - Privacy, Data Protection, Mobile ICT, Ambient Intelligence, Social Norms KW - Data Protection KW - Mobile ICT KW - Ambient Intelligences KW - Social Norm Y1 - 2005 UR - https://www.researchgate.net/publication/263818596_Privacy_personal_data_protection_and_the_need_to_differentiate ER - TY - CHAP A1 - Weber, Karsten ED - Abel, G. T1 - Computersimulationen im Entdeckungszusammenhang T2 - Kreativität. Proceedings des XX. Deutschen Kongresses für Philosophie Y1 - 2005 UR - https://www.researchgate.net/publication/263818593_Computersimulationen_im_Entdeckungszusammenhang PB - Universitätsverlag der TU Berlin CY - Berlin ER - TY - CHAP A1 - Weber, Karsten ED - Neumaier, O. ED - Sedmak, Clemens ED - Zichy, M. T1 - Die andere Seite der Verteilungsgerechtigkeit T2 - Philosophische Perspektiven. Beiträge zum VII. Österreichischen Kongress für Philosophie Y1 - 2005 UR - https://www.researchgate.net/publication/263818730_Die_andere_Seite_der_Verteilungsgerechtigkeit PB - Ontos CY - Lancaster ER - TY - CHAP A1 - Drüeke, Ricarda A1 - Haug, Sonja A1 - Keller, Werner A1 - Weber, Karsten ED - Koschke, Rainer T1 - Verhalten und Einstellungen zum Mobiltelefonieren T2 - Informatik 2007 - Informatik trifft Logistik, Band 1 der Proceedings zur 37. Jahrestagung der Gesellschaft für Informatik e.V. (GI); 24.-27. September 2007 in Bremen Y1 - 2007 SN - 978-3-88579-203-1 SP - 354 EP - 358 PB - Gesellschaft für Informatik e. V. CY - Bonn ER - TY - CHAP A1 - Nagenborg, Michael A1 - Weber, Karsten ED - Koschke, Rainer T1 - Ubiquitous Computing, Pervasive Computing, Ambient Intelligence ... Surveillance and Control? T2 - Informatik 2007 - Informatik trifft Logistik, Band 1 der Proceedings zur 37. Jahrestagung der Gesellschaft für Informatik e.V. (GI); 24.-27. September 2007 in Bremen Y1 - 2007 SN - 978-3-88579-203-1 SP - 329 EP - 333 PB - Gesellschaft für Informatik e.V. CY - Bonn ER - TY - CHAP A1 - Weber, Karsten ED - Decker, Michael ED - Grunwald, Armin ED - Knapp, Martin T1 - Ubiquitäre Informations- und Kommunikationstechnologie BT - Grenzen der Voraussehbarkeit und Gestaltung T2 - Der Systemblick auf Innovation - Technikfolgenabschätzung in der Technikgestaltung Y1 - 2012 SP - 319 EP - 326 PB - Edition Sigma CY - Berlin ER - TY - CHAP A1 - Weber, Karsten ED - Ohly, Heinz Peter T1 - Informationsnachhaltigkeit. Vom schwierigen Umgang mit Informationsgütern T2 - Wissen - Wissenschaft - Organisation. Proceedings der 12. Tagung der Deutschen Sektion der Internationalen Gesellschaft für Wissensorganisation ; Bonn, 19. bis 21. Oktober 2009 Y1 - 2013 SP - 19 EP - 31 PB - Ergon CY - Würzburg ER - TY - CHAP A1 - Weber, Karsten ED - Rothärmel, Sonja ED - Schmidt, K.W. ED - Wolfslast, G. T1 - Wer bestimmt über den Tod? Interventionsrechtete von Familienangehörigen und anderen Personen T2 - Familie versus Patientenautonomie? Zur Rolle der Familie bei Behandlungsentscheidungen ; Tagungsband der Taunus Winter School Y1 - 2006 SN - 978-3-89846-436-9 PB - Haag + Herchen CY - Frankfurt am Main ER - TY - CHAP A1 - Mendel, Robert A1 - Souza Jr., Luis Antonio de A1 - Rauber, David A1 - Papa, João Paulo A1 - Palm, Christoph T1 - Semi-supervised Segmentation Based on Error-Correcting Supervision T2 - Computer vision - ECCV 2020: 16th European conference, Glasgow, UK, August 23-28, 2020, Proceedings, Part XXIX N2 - 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. KW - Semi-Supervised Learning KW - Machine Learning Y1 - 2020 SN - 978-3-030-58525-9 U6 - https://doi.org/10.1007/978-3-030-58526-6_9 SP - 141 EP - 157 PB - Springer CY - Cham ER - TY - CHAP A1 - Brosig, Christoph A1 - Westner, Markus A1 - Strahringer, Susanne T1 - Revisiting the Concept of IT Capabilities in the Era of Digitalization T2 - 2020 IEEE 22nd Conference on Business Informatics (CBI 2020): Antwerp, Belgium, 22-24 June 2020, proceedings N2 - 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. KW - Digital technologies KW - IT capabilities KW - Resource-based view KW - Informationstechnik KW - Digitalisierung KW - Fähigkeit KW - Kompetenz KW - Ressourcenorientierter Ansatz KW - Wettbewerbsvorteil Y1 - 2020 U6 - https://doi.org/10.1109/CBI49978.2020.00017 SP - 84 EP - 93 PB - IEEE ER - TY - CHAP A1 - Weber, Karsten A1 - Wackerbarth, Alena ED - Hofstedt, Petra ED - Meer, Klaus ED - Schmitt, Ingo T1 - Partizipative Gestaltung verlässlicher Assistenzsysteme für die Pflege alter und hochbetagter Menschen T2 - Informatik'2015: 45. Jahrestagung der Gesellschaft für Informatik, Informatik, Energie und Umwelt, Tagung von 28. September - 2. Oktober 2015 in Cottbus N2 - 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. Dafür müssen diese Systeme hochverlässlich sein, aber gleichzeitig auch Erwartungen erfüllen, die weniger im technischen und stärker im sozialen Bereich angesiedelt sind. Nach einer kurzen Einführung der Geschichte dieser Systeme und der Beschreibung des Stands der Technik soll auf verschiedene Evaluationswerkzeuge eingegangen werden, die dazu genutzt werden können, eine partizipative Technikgestaltung von AAL-Systemen zu unterstützen Y1 - 2015 SP - 1247 EP - 1249 PB - Gesellschaft für Informatik CY - Bonn ER - TY - CHAP A1 - Fuhrmann, Thomas T1 - Let the students publish T2 - IEEE International Conference on Teaching, Assessment and Learning for Engineering (TALE), 26-29 August 2013, Bali Dynasty Resort, Kuta, Indonesia N2 - 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. KW - Education KW - Engineering education KW - Educational technology KW - Student project Y1 - 2013 SN - 978-1-4673-6355-6 U6 - https://doi.org/10.1109/TALE.2013.6654515 PB - IEEE ER - TY - CHAP A1 - Altenbuchner, Amelie A1 - Weber, Karsten A1 - Fuchs, Dominik ED - Friedrich, Petra ED - Fuchs, Dominik T1 - Nützlichkeit und Nutzung BT - Technikakzeptanz und Technikbewertung von AAL T2 - Assistive Technik für selbstbestimmtes Wohnen, 6. Ambient Medicine® Forum 19.-20. Februar 2019 KW - AAL-Technik KW - Technikbewertung KW - Akzeptanz KW - Technik KW - Risiko Y1 - 2019 SP - 149 EP - 156 PB - Cuvillier CY - Göttingen ER - TY - CHAP A1 - Weber, Karsten A1 - Scorna, Ulrike A1 - Haug, Sonja ED - Weidner, Robert ED - Karafillidis, Athanasios T1 - ELSI in Serious Games für die technikunterstützte medizinische Ausbildung: das Beispiel HaptiVisT T2 - 3. Transdisziplinäre Konferenz "Technische Unterstützungssysteme, die die Menschen wirklich wollen", 11.-12.12.2018, Hamburg N2 - Das haptisch-visuelle Trainingssystem HaptiVisT zur Unterstützung der chirurgischen Ausbildung für zwei chirurgische Anwendungsfelder (Cochlea-Implantationen und minimalinvasive Handchirurgie) im Rahmen eines Serious Games berührt 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 stützen sich auf eine empirisch basierte Anforderungsanalyse aus Anwender- und Entwicklersicht. KW - Unterstützungstechnologie KW - Medizinische Ausbildung KW - Handchirurgie KW - Cochlea-Implantat KW - Haptische Feedback-Technologie Y1 - 2019 SN - 978-3-86818-245-3 SP - 187 EP - 194 PB - Helmut-Schmidt-Universität CY - Hamburg ER - TY - CHAP A1 - Klotz, Stefan A1 - Westner, Markus A1 - Strahringer, Susanne T1 - From Shadow IT to Business-managed IT and Back Again BT - How Responsibility for IT Instances Evolves Over Time T2 - Pacific Asia Conference on Information Systems (PACIS): 2020, Dubai N2 - 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. KW - IT-Governance KW - Shadow IT KW - Business-managed IT KW - Shadow IT KW - Business-managed IT KW - IT governance KW - trajectory KW - application governance Y1 - 2020 UR - https://aisel.aisnet.org/pacis2020/94/ ER - TY - CHAP A1 - Palm, Christoph A1 - Scholl, Ingrid A1 - Lehmann, Thomas M. A1 - Spitzer, Klaus ED - Lehmann, Thomas M. ED - Scholl, Ingrid ED - Spitzer, Klaus T1 - Trennung von diffuser und spiegelnder Reflexion in Farbbildern des Larynx zur Untersuchung von Farb- und Formmerkmalen der Stimmlippen T2 - Bildverarbeitung für die Medizin. Algorithmen, Systeme, Anwendungen. Proceedings des Aachener Workshops am 8. und 9. November 1996 N2 - Zur diagnostischen Unterstützung bei der Befundung laryngealer Erkrankungen soll eine Farb- und Formanalyse der Stimmlippen durchgeführt 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 beleuchtungsunabhängigen Objektfarbe, während deren Wichtungsfaktoren als Eingabe für Shape-from-Shading-Verfahren zur Oberflächenrekonstruktion dienen. KW - Laryngoskopie KW - Farbbild KW - Reflexion Y1 - 1996 UR - https://scholar.google.de/citations?user=nc0XkcMAAAAJ&hl=fa#d=gs_md_cita-d&u=%2Fcitations%3Fview_op%3Dview_citation%26hl%3Dfa%26user%3Dnc0XkcMAAAAJ%26citation_for_view%3Dnc0XkcMAAAAJ%3AqjMakFHDy7sC%26tzom%3D-120 SP - 229 EP - 234 PB - Verlag der Augustinus-Buchhandlung CY - Aachen ER - TY - CHAP A1 - Hassan, H. A1 - Ilgner, Justus F. R. A1 - Palm, Christoph A1 - Lehmann, Thomas M. A1 - Spitzer, Klaus A1 - Westhofen, Martin ED - Lehmann, Thomas M. ED - Spitzer, Klaus ED - Tolxdorff, Thomas T1 - Objective Judgement of Endoscopic Laryngeal Images T2 - Advances in Quantitative Laryngoscopy, Voice and Speech Research, Proceedings of the 3rd International Workshop, RWTH Aachen N2 - 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. KW - Laryngoscopy KW - Diagnosis KW - Image processing KW - Quantitative Image analysis KW - Colorconstancy Y1 - 1998 UR - https://citeseerx.ist.psu.edu/doc_view/pid/caf5bedf5cf68ed3be68054b140a1241f4f278e2 SP - 135 EP - 142 ER - TY - CHAP A1 - Scholl, Ingrid A1 - Palm, Christoph A1 - Sovakar, Abhijit A1 - Lehmann, Thomas M. A1 - Spitzer, Klaus ED - Arnolds, B. ED - Mueller, H. ED - Saupe, D. ED - Tolxdorff, Thomas T1 - Quantitative Analyse der Stimmlippen T2 - 5. Workshop Digitale Bildverarbeitung in der Medizin, Universität Freiburg, 10.-11. März 1997 KW - Konturverfolgung KW - Snakes KW - Farbanalyse KW - Dichromatisches Reflexionsmodell KW - Farbkonstanz KW - Laryngoskopie Y1 - 1997 UR - https://pdfs.semanticscholar.org/9a0c/9e7dc883ccf6e8a8a686c28422238adb5f35.pdf SP - 81 EP - 86 ER - TY - CHAP A1 - Palm, Christoph A1 - Scholl, Ingrid A1 - Lehmann, Thomas M. A1 - Spitzer, Klaus ED - Lehmann, Thomas M. ED - Metzler, V. ED - Spitzer, Klaus ED - Tolxdorff, Thomas T1 - Quantitative Farbmessung in laryngoskopischen Bildern T2 - Bildverarbeitung für die Medizin N2 - Quantitative Farbmessungen sollen die Diagnostik laryngealer Erkrankungen unterstützen. 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 Körperfarbe entspricht dabei der gewebespezifischen Reflexion, die Oberfächenfarbe der Strahlung der Lichtquelle. KW - Farbkonstanz KW - quantitative Farbmessung KW - dichromatisches Reflexionsmodell KW - Laryngoskopie Y1 - 1998 U6 - https://doi.org/10.1007/978-3-642-58775-7_81 SP - 412 EP - 416 PB - Springer CY - Berlin ER - TY - CHAP A1 - Palm, Christoph A1 - Scholl, Ingrid A1 - Lehmann, Thomas M. A1 - Spitzer, Klaus ED - Greiser, E. ED - Wischnewsky, M. T1 - Nutzung eines Farbkonstanz-Algorithmus zur Entfernung von Glanzlichtern in laryngoskopischen Bildern T2 - Methoden der Medizinischen Informatik, Biometrie und Epidemiologie in der modernen Informationsgesellschaft N2 - 1 Einführung Funktionelle und organische Störungen im Larynx beeinträchtigen die Ausdrucksfähigkeit 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 unabhängige Aufnahme der drei Farbkanäle erlaubt. Die bisherige subjektive Befundung ist von der Erfahrung des Untersuchers abhängig und läßt nur eine grobe Klassifikation der Krankheitsbilder zu. Zur Objektivierung werden daher quantitative Parameter für 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 führen und so weite Bereiche der Stimmlippen für die Farb-und Texturanalyse unbrauchbar machen. Dieser Beitrag stellt einen Farbkonstanz-Algorithmus vor, der unabhängig von der Lichtquelle quantitative Farbwerte des Gewebes liefert und die Glanzlichtdetektion und -elimination ermöglicht. 2 Methodik Ziel des Farbkonstanz-Algorithmus ist die Trennung von Lichtquellen-und Gewebefarbe. Unter Verwendung des dichromatischen Reflexionsmodells [1] kann die Oberflächenreflexion mit der Farbe der Lichtquelle und die Körperreflexion mit der Gewebefarbe identifiziert werden. Der Farbeindruck entsteht aus der Linearkombination beider Farbkomponenten. Ihre Gewichtung ist von der Aufnahmegeometrie abhängig, insbesondere vom Winkel zwischen Oberflächennormalen und dem Positionsvektor der Lichtquelle. In einem zweistufigen Verfahren wird zunächst die Lichtquellenfarbe geschätzt, dann die Gewebefarbe ermittelt. Hieraus können beide Farbanteile durch die Berechnung der Gewichtsfaktoren pixelweise getrennt werden. KW - Farbkonstanz KW - Glanzlichtelimination KW - medizinische Bildverarbeitung KW - dichromatisches Reflexionsmodell Y1 - 1998 SN - 9783820813357 SP - 300 EP - 303 PB - MMV Medien und Medizin CY - München ER - TY - CHAP A1 - Palm, Christoph A1 - Pelkmann, Annegret A1 - Lehmann, Thomas M. A1 - Spitzer, Klaus T1 - Distortion Correction of Laryngoscopic Images T2 - Advances in quantitative laryngoscopy, voice and speech research, Proceedings of the 3rd international workshop Aachen, RWTH N2 - 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. KW - image distortion KW - camera calibration KW - multiple regression analysis Y1 - 1998 UR - https://pdfs.semanticscholar.org/e9d8/eb27af24bd79f482821441c2bf0eee7b3fe6.pdf?_ga=2.183754286.985176231.1591560247-1467258391.1581026068 SP - 117 EP - 125 ER - TY - CHAP A1 - Palm, Christoph A1 - Neuschaefer-Rube, C. A1 - Lehmann, Thomas M. A1 - Spitzer, Klaus ED - Evers, H. ED - Glombitza, G. ED - Lehmann, Thomas M. ED - Meinzer, H.-P. T1 - Wissensbasierte Bewegungskompensation in aktiven Konturmodellen T2 - Bildverarbeitung für die Medizin N2 - Zur Analyse von Lippenbewegungsabläufen wird ein aktives Konturmodell eingesetzt. Probleme bereitet die hohe Sprechgeschwindigkeit, die in star ken Objektverschiebungen result iert und bislang nicht durch eine alleinige Konturanpassung kompensiert werden kann. In diesem Beitrag werden die klassischen aktiven Konturmodelle um eine Vorjustierung der Grobkonturen erweitert, die eine energiebasierte Konturanpassung erst möglich macht. Die Schätzung der Verschiebung zur Vorjustierung basiert auf dem Gradientenbild und einem prädikatenlogisch formulierten Regelwerk, das Annahmen und Nebenbedingungen als Wissensbasis enthält. Mit Hilfe dieser Erweiterungen ist eine automatisierte Konturverfolgung der Lippen möglich. KW - Aktives Konturmodell KW - Pradikatenlogik KW - Bewegungsschatzung Y1 - 1999 U6 - https://doi.org/10.1007/978-3-642-60125-5_2 SP - 8 EP - 12 PB - Springer CY - Berlin ER - TY - CHAP A1 - Palm, Christoph A1 - Metzler, V. A1 - Moham, B. A1 - Dieker, O. A1 - Lehmann, Thomas M. A1 - Spitzer, Klaus ED - Evers, H. ED - Glombitza, G. ED - Lehmann, Thomas M. ED - Meinzer, H.-P. T1 - Co-Occurrence Matrizen zur Texturklassifikation in Vektorbildern T2 - Bildverarbeitung für die Medizin N2 - Statistische Eigenschaften natürlicher Grauwerttexturen werden mit Co-Occurrence Matrizen, basierend auf der Grauwertstatistik zweiter Ordnung, modelliert. Die Matrix gibt dann die apriori Wahrscheinlichkeiten aller Grauwertpaare an. Da in der medizinischen Bildverarbeitung verstärkt Multispektralbilder ausgewertet werden, wird das bekannte Konzept hier auf beliebige Vektorbilder erweitert. Dadurch kann bei der Texturklassifikation die zur Verfügung stehende Information vollständig genutzt werden. Insbesondere zur Detektion von Farbtexturen ist dieser Ansatz geeignet, da Wertepaare unterschiedlicher Spektralebenen ausgewertet werden können. Ebenso kann die Methode auch bei der Multiskalendekomposition von Intensitätsbildern zur Verbesserung der Texturerkennung beitragen. Die in den Matrizen entstehenden Muster lassen dann über die Extraktion geeigneter Texturdeskriptoren Rückschlüsse auf die Texturen des Bildes zu. KW - Texturerkennung KW - Vektorbilder KW - Multispektralbilder KW - Multiskalenbilder KW - Klassifikation Y1 - 1999 U6 - https://doi.org/10.1007/978-3-642-60125-5_69 SP - 367 EP - 371 PB - Springer CY - Berlin ER - TY - CHAP A1 - Palm, Christoph A1 - Lehmann, Thomas M. A1 - Spitzer, Klaus T1 - Bestimmung der Lichtquellenfarbe bei der Endoskopie mikrotexturierter Oberflächen des Kehlkopfes T2 - 5. Workshop Farbbildverarbeitung, Ilmenau, 1999 N2 - Zur Unterstützung der Diagnose von Stimmlippenerkrankungen werden innerhalb des Forschungsprojektes Quantitative Digitale Laryngoskopie objektive Parameter zur Beschreibung der Bewegung, der Farbe sowie der Form der Stimmlippen entwickelt und klinisch evaluiert. Während die Bewegungsanalyse Aufschluß über funktionelle Stimmstörungen gibt, beschreiben Parameter der Farb- und Formanalyse morphologische Veränderungen des Stimmlippengewebes. In diesem Beitrag werden die Methoden und bisherigen Ergebnisse zur Bewegungs- und Farbanalyse vorgestellt. Die Bewegungsanalyse wurde mit einem erweiterten Konturmodell (Snakes) durchgeführt. Aufgrund des modifizierten Konturmodells konnten die Konturen der Stimmlippen automatisch über die gesmate Bildsequenz zuverlässig detektiert werden. Die Vermssung der Konturen liefert neue quantitative Parameter zur Befundung von laryngoskopischen Stimmlippenaufnahmen. Um die Farbeigenschaften der Stimmlippen zu bestimmen, wurde ausgehend vom RGB-Bild die Objektfarbe unabhängig von der Farbe der Lichtquelle durch Verwendung von Clusterverfahren und der Viertelkreisanalyse berechnet. Mit dieser Farbanalyse konnte die Farbe der Lichtquelle ermittelt und das beleuchtungsunabhängige Farbbild berechnet werden. Die Quanitifizierung der Rötung der Stimmlippen ist z.B. ein entscheidendes Kriterium zur Diagnostik der akuten Laryngitis. KW - Konturverfolgung KW - Snakes KW - Dichromatisches Reflexionsmodell KW - Farbkonstanz KW - Laryngoskopie Y1 - 1999 UR - http://www.germancolorgroup.de/html/Vortr_99_pdf/01_Palm.pdf SP - 3 EP - 10 ER - TY - CHAP A1 - Palm, Christoph A1 - Keysers, Daniel A1 - Lehmann, Thomas M. A1 - Spitzer, Klaus T1 - Gabor Filtering of Complex Hue/Saturation Images for Color Texture Classification T2 - Proceedings of the 5th Joint Conference on Information Science (JCIS) 2, The Association for Intelligent Machinery, Atlantic City, NJ, 2000 N2 - Objective: Complex hue/saturation images as a new approach for color texture classification using Gabor filters are introduced and compared with common techniques. Method: The interpretation of hue and saturationas polar coordinates allows direct use of the HSV-colorspace for Fourier transform. This technique is applied for Gabor feature extraction of color textures. In contrast to other color features based on the RGB-colorspace [1] the combination of color bands is done previous to the filtering. Results: The performance of the new HS-featuresis compared with that of RGB based as well as grayscale Gabor features by evaluating the classifi-cation of 30 natural textures. The new HS-featuresshow same results like the best RGB features but allow a more compact representation. On the averagethe color features improve the results of grayscale features. Conclusion: The consideration of the color information enhances the classification of color texture. The choice of colorspace cannot be adjudged finally, but the introduced features suggest the use of the HSV-colorspace with less features than RGB. Y1 - 2000 UR - http://www.keysers.net/daniel/files/JCIS2000_palm.pdf SP - 45 EP - 49 ER - TY - CHAP A1 - Horn, Lars-Christian A1 - Pippig, S. A1 - Raptis, Georgios A1 - Fischer, Uta A1 - Köhler, U. A1 - Hentschel, Bettina A1 - Martin, Rosemarie T1 - Tumorassoziierte Proteolyse beim Zervixkarzinom BT - Vortrag T2 - 87. Tagung der Deutschen Gesellschaft für Pathologie, 14. Juni 2003 KW - Gebärmutterhalskrebs KW - Chirurgie KW - Tumorassoziierte Proteolyse KW - Immuncytochemie KW - Zelladhäsion Y1 - 2003 ER - TY - CHAP A1 - Höh, H. A1 - Raptis, Georgios T1 - Applications of the Erbium: YAG Laser in Ophthalmology - Cataracta-, Glaukoma-, Eyelid-Surgery and pars plana Vitrectomy BT - Symposium on Cataract, IOL, and Refractive Surgery. Boston, 20.05.2000 und 22.05.2000 N2 - Recent developments in lasers have provided us the possibility of laser ocular surgery. The xenon, argon, neodymium:YAG and dye lasers have been successfully used in out-patient clinics. The excimer laser has been attracting researchers' interest in the new application of laser to cornea and lens. The erbium:YAG laser emits a 2.94-microns beam that can ablate the transparent ocular tissues such as lenses and corneas. The author has applied this laser to the cornea, lens, vitreous and other ocular tissues. The erbium:YAG laser beam was directed through a 1.5-meter-long, 200-microns-diameter fiberoptic guide. The radiant energy measured about 50 mJ at the end of the probe. The laser was emitted as a 400-microsecond pulse. Freshly enucleated rabbit eyes were used in this study. Laser burns were applied to the tissue surface at various energy settings. At minimal power, the tissues were coagulated by the erbium:YAG laser application. At a power of more than 636-954 mJ/mm2, tissue began to evaporate; the tissue loss was observed under a surgical light microscope. Corneal photoablation, lens ablation, iridotomy, trabeculotomy, cutting of the vitreous and retinal ablation were easily performed. Like the excimer laser, the erbium:YAG laser is a potential tool for ocular surgery. KW - Augenchirurgie KW - YAG-Laser KW - Erbium-Laser Y1 - 2000 ER - TY - CHAP A1 - Raptis, Georgios T1 - Die Konzepte und Mechanismen der elektronischen Gesundheitskarte und des Heilberufsausweises aus der Sicht der Datensicherheit / des Datenschutzes BT - Vortrag T2 - Forschungsseminar med. Informatik an der Universität Heidelberg, 22.06.2006 KW - Elektronische Gesundheitskarte KW - Heilberuf KW - Ausweis KW - Datenschutz KW - Datensicherheit Y1 - 2005 ER - TY - CHAP A1 - Raptis, Georgios T1 - Empfehlungen der BÄK zum Datenschutz im Praxisalltag, Darstellung unter technischen Aspekten BT - Vortrag im Rahmen der conhIT 2009, Berlin, 22.04.2009, zertifiziert von der Ärztekammer Berlin T2 - conhIT 2009, Berlin, 22.04.2009 KW - Arztpraxis KW - Datenschutz Y1 - 2009 ER - TY - CHAP A1 - Raptis, Georgios T1 - Health Professional eIDs vis-á-vis a Single Market Perspective BT - Vortrag T2 - European Health Telematics Association, Berlin, 25.10.2011 KW - eArztausweis KW - Elektronischer Arztausweis Y1 - 2011 ER - TY - CHAP A1 - Wiesmaier, Alexander A1 - Lippert, Markus A1 - Karatsiolis, Vangelis A1 - Raptis, Georgios A1 - Buchmann, Johannes T1 - An Evaluated Certification Services System for the German National Root CA - Legally Binding and Trustworthy Transactions in E-Business and E-Government T2 - Proceedings of The 2005 International Conference on E-Business, Enterprise Information Systems, E-Government, and Outsourcing, EEE 2005, Las Vegas, Nevada, USA, June 20-23, 2005 Y1 - 2005 SN - 1-932415-76-9 SP - 103 EP - 108 PB - CSREA Press ER - TY - CHAP A1 - Raptis, Georgios T1 - Notfalldaten und Datenerhalt mit der elektronischen Gesundheitskarte. T2 - Tagungsband 22. Smartcard-Workshop 2012 KW - Elektronische Gesundheitskarte KW - Notfallmedizin KW - Datensicherung Y1 - 2012 SP - 166 PB - Fraunhofer-Verlag ER - TY - CHAP A1 - Raptis, Georgios T1 - Ein Verfahren zur Lösung des Problems der kryptographischen Langzeitsicherheit medizinischer Daten, die in einer Infrastruktur gespeichert werden T2 - BIOSIG-Konferenz 2007, Darmstadt N2 - Medizinische Daten, die - wie derzeit für die Telematik-Infrastruktur nach §291a SGB V spe-zifiziert - auch außerhalb der physischen Kontrolle der Eigentümer oder Ersteller (also z.B. außerhalb von Arztpraxen oder Klinken) auf Servern kryptographisch verschlüsselt gespeichert werden, müssen sehr lange vertraulich bleiben. Insbesondere darf der technische Betreiber des Servers, der die Daten speichert, keinen Zugriff erlangen. Es kann jedoch keine verlässliche Aussage dahingehend getroffen werden, ob die heute eingesetzten kryp-tographischen Algorithmen in 30 oder 40 Jahren die Vertraulichkeit der medizinischen Daten weiterhin gewährleisten. Es wird ein Verfahren vorgestellt, welches das Problem der langfristigen Sicherheit von verschlüsselt gespeicherten medizinischen Daten aus kryptographischer Sicht löst. Die Anwendung des Verfahrens wird am Beispiel einer nach den derzeit bekannten gematik-Spezifikationen definierten Infrastruktur veranschaulicht. Es wird von einer getrennten Speicherung von verschlüsselten medizinischen Daten und Schlüsselmaterial ausgegangen. Die Daten werden an der Datenquelle (Konnektor, z.B. eines Arztes) mit einem Einmalblock (One Time Pad, OTP) verschlüsselt. Sie sind damit beweisbar sicher verschlüsselt, weil das One-Time-Pad-Verschlüsselungsverfahren beweisbar „perfekt geheim“ ist. Der OTP-Schlüssel wird mit einem symmetrischen Schlüssel verschlüsselt, der wiederum mit den asymmetrischen Schlüsseln aller Zugriffsberechtigten verschlüsselt wird. Die kryptographische, technische und organisatorische Sicherheit des Verfahrens sowie seine Voraussetzungen und Kosten werden analysiert. KW - Gesundheitsinformationssystem KW - Datensicherhung KW - Kryptologie Y1 - 2007 UR - http://www.baek.de/downloads/Raptis_Verfahren-2.pdf ER - TY - CHAP A1 - Metzler, V. A1 - Aach, T. A1 - Palm, Christoph A1 - Lehmann, Thomas M. T1 - Texture Classification of Graylevel Images by Multiscale Cross-Co-Occurrence Matrices T2 - Proceedings 15th International Conference on Pattern Recognition (ICPR-2000) N2 - Local gray level dependencies of natural images can be modelled by means of co-occurrence matrices containing joint probabilities of gray-level pairs. Texture, however, is a resolution-dependent phenomenon and hence, classification depends on the chosen scale. Since there is no optimal scale for all textures we employ a multiscale approach that acquires textural features at several scales. Thus linear and nonlinear scale-spaces are analyzed by multiscale co-occurrence matrices that describe the statistical behavior of a texture in scale-space. Classification is then performed on the basis of texture features taken from the individual scale with the highest discriminatory power. By considering cross-scale occurrences of gray level pairs, the impact of filters on the feature is described and used for classification of natural textures. This novel method was found to improve classification rates of the common co-occurrence matrix approach on standard textures significantly. Y1 - 2000 U6 - https://doi.org/10.1109/ICPR.2000.906133 SP - 549 EP - 552 ER - TY - CHAP A1 - Palm, Christoph A1 - Lehmann, Thomas M. A1 - Spitzer, Klaus T1 - Color Texture Analysis of Moving Vocal Cords Using Approaches from Statistics and Signal Theory T2 - Advances in Quantitative Laryngoscopy, Voice and Speech Research, Procs. 4th International Workshop, Friedrich Schiller University, Jena N2 - Textural features are applied for detection of morphological pathologies of vocal cords. Cooccurrence matrices as statistical features are presented as well as filter bank analysis by Gabor filters. Both methods are extended to handle color images. Their robustness against camera movement and vibration of vocal cords is evaluated. Classification results due to three in vivo sequences are in between 94.4 % and 98.9%. The classification errors decrease if color features are used instead of grayscale features for both statistical and Fourier features KW - Color Texture KW - Gabor Filter KW - Cooccurrence Matrix KW - Image Processing Y1 - 2000 SP - 49 EP - 56 ER - TY - CHAP A1 - Palm, Christoph A1 - Fischer, B. A1 - Lehmann, Thomas M. A1 - Spitzer, Klaus T1 - Hierarchische Wasserscheiden-Transformation zur Lippensegmentierung in Farbbildern T2 - Bildverarbeitung für die Medizin 2000 N2 - Zur Lösung komplexer Segmentierungsprobleme wird eine hierarchische und farbbasierte Wasserscheidentransformation vorgestellt. Geringe Modifikationen bezüglich Startpunktwahl und Flutungsprozess resultieren in signifikanten Verbesserungen der Segmentierung. Das Verfahren wurde zur Lippendetektion in Farbbildsequenzen eingesetzt, die zur quantitativen Beschreibung von Sprechbewegungsabläufen automatisch ausgewertet werden. Die Experimente mit 245 Bildern aus 6 Sequenzen zeigten eine Fehlerrate von 13%. KW - Hierarchische Wasserscheiden-Transformation KW - Segmentierung der Lippen KW - Bewegungsanalyse KW - Farbbildverarbeitung Y1 - 2000 U6 - https://doi.org/10.1007/978-3-642-59757-2_20 SP - 106 EP - 110 PB - Springer CY - Berlin ER - TY - CHAP A1 - Aurbach, Maximilian A1 - Wagner, Kilian A1 - Süß, Franz A1 - Dendorfer, Sebastian ED - Badnjevic, Almir T1 - Implementation and Validation of Human Kinematics Measured Using IMUs for Musculoskeletal Simulations by the Evaluation of Joint Reaction Forces T2 - CMBEBIH 2017, Proceedings of the International Conference on Medical and Biological Engineering 2017, Sarajevo, Bosnia and Herzegovina N2 - The gold standard for the analysis of human kinematics and kinetics is a camera-based motion capture system in combination with force measurement platforms. Alternatively, inertial measurement units can be utilized to obtain human kinematics, while ground reaction forces are computed from full body dynamics. This setup represents a system independent from the spatial confinement of a gait laboratory. The aim of this study is the comparison of the two methods by the investigation of lower limb kinematics and the resulting joint reaction forces within the ankle-, knee- and hip joints. For this purpose, human motion during gait was captured simultaneously by both measurement techniques. 13 trials from 8 different test subjects were evaluated in total. IMU data was processed with a quaternion based Kalman Filter. The data sets were implemented into a musculoskeletal simulation program in order to drive a virtual human body model. Each sensor was aligned to the gravitational and magnetic field vectors of the earth. The angles of flexions, extensions and rotations were analyzed to determine kinematic differences. Joint reaction forces defined kinetic dissimilarities. The overall kinematic differences of both models yielded root mean square errors of 7.62°, 6.02°, 4.95°, 2.79°, 2.38° and 3.56° for ankle flexion, subtalar eversion, knee flexion, hip external rotation, hip abduction and hip flexion, respectively. The proximo-distal differences in force peaks between the models yielded overall for the ankle, 57.33 %Bodyweight(BW) ± 46.86 %BW (16.66 %(Maximum peak to peak) ± 13.62 %) for the knee 37.09 %BW ± 29.33 %BW (17.65 % ± 15.44 %) and 32.03 %BW ± 24.33 %BW (15.6 % ± 12.54 %) for the hip. The overall outcome of this work investigated an approach independent of the common setup of the gait laboratory, thus enabling a cheaper and more flexible technology as an alternative. However, kinematic and thus kinetic differences remain rather large. Future work aims to improve the contact criterion for the calculation of the ground reaction forces and the implementation of a full-body calibration algorithm for the IMU system in order to counteract magnetic field disturbances. KW - Inertial Measurement Units KW - Multibody Simulation KW - Musculoskeletal Simulation KW - AnyBody KW - Motion Capture KW - Bewegungsapparat KW - Biomechanik KW - Motion Capturing KW - Mehrkörpersimulation KW - Ground Reaction Force Prediction KW - Gait KW - IMU KW - Joint Reaction Forces Y1 - 2017 U6 - https://doi.org/10.1007/978-981-10-4166-2_31 VL - Vol. 62 SP - 205 EP - 211 PB - Springer CY - Singapore ER - TY - CHAP A1 - Jungtäubl, Dominik A1 - Schmitz, Paul A1 - Gross, Simon A1 - Dendorfer, Sebastian ED - Badnjevic, Almir T1 - FEA of the transiliacal internal fixator as an osteosynthesis of pelvic ring fractures T2 - CMBEBIH 2017, Proceedings of the International Conference on Medical and Biological Engineering 2017 N2 - Common Schanz screw systems can be used to stabilize pelvic ring fractures. In order to accommodate for different patient’s requirements, implants can be placed in cranio-caudal direction into the os ilium (T1), or into the supraacetabular bone canal, and thus, in dorso-ventral direction (T2). Whereas both techniques are currently used, no data of the biomechanical behavior is available up to this date. The aim of this study is to analyze, whether T2 shows biomechanical advantages with respect to tissue and implant stresses due to the enlarged bone-implant interface. Forces acting on the pelvis were analyzed using motion capture data of a gait cycle obtained by the utilization of a musculoskeletal simulation program. A three dimensional finite element (FE) model of the pelvis with grayscale-based material properties was generated. The muscle and joint reaction forces at toe-off were applied to the FE model and instable pelvis fractures were implemented. The osteosynthesis systems were positioned within the model in order to enable the comparison between the two different surgical techniques. Stresses and displacements were analyzed for bone tissue, fracture zone and implant. T2 lead to approx. 30% larger displacements in the fracture zone. Von-Mises stresses were larger for T2 in the implant (80 MPa vs. 227 MPa), whereas T1 leads to larger stresses in the bone tissue (200 MPa vs. 140 MPa). Both implantation techniques showed a good biomechanical behavior. Differences could be found with respect to tissue strains and deformations in the fracture zone. If bone quality or fracture healing are of concern, T2 or T1 should be used, respectively. However, both techniques seem to be applicable for cases with no special requirements. Further analyses aim to investigate the behavior under cyclic loading. KW - Finite element analysis KW - Musculoskeletal simulation KW - Internal fixator KW - Pelvic ring fracture KW - Beckenbruch KW - Operationstechnik KW - Finite-Elemente-Methode KW - Biomechanik KW - Simulation Y1 - 2017 SN - 978-981-10-4165-5 U6 - https://doi.org/10.1007/978-981-10-4166-2_32 SP - 212 EP - 217 PB - Springer CY - Singapore ER - TY - CHAP A1 - Weber, Tim A. A1 - Dendorfer, Sebastian A1 - Dullien, Silvia A1 - Grifka, Joachim A1 - Verkerke, Gijsbertus Jacob A1 - Renkawitz, Tobias T1 - Measuring functional outcome after total hip replacement with subject-specific hip joint loading T2 - Proceedings of the Institution of Mechanical Engineers. Part H, Journal of engineering in medicine N2 - Total hip replacement is an often-performed orthopedic surgical procedure; the amount of procedures undertaken will increase since our life expectancy is growing. In order to optimize function, hip biomechanics should be restored to as near normal as possible. The goal of this pilot study was to determine whether or not it is feasible to compute the vectorial hip reaction force pathways on the head of the prosthesis and the force angles relative to the cup of the prosthesis that occur during gait in total hip replacement patients, serving as an objective measurement of the functional outcome following hip replacement. A three-dimensional gait analysis, measuring ground reaction forces and kinematics, was performed. The data retrieved from the gait analysis was used as the input for the musculoskeletal model to compute vectorial joint reaction forces for data processing. To evaluate the position and orientation of the joint reaction forces, the force path, as well as the force angles for the operated and non-operated joint, has been calculated during the stance phase of the specific leg. The force path for subject 2 on the non-operated side is only located in the posterior-lateral quarter, as is the force path for subject 1. In contrast to this subject, the force path for subject 2 at the operated hip joint can be found only within the anterior quarter of the head of the implant, where it is nearly equally distributed in the medio-lateral half of the prosthesis head. The force-inclination angles on the cup of subject 1, with respect to the plane of the socket face, indicates that the force vector is mainly positioned in the same quadrant when compared with subject 2 (in a cup-fixed coordinate system). The force-anteversion angle behaves similarly to the force-inclination angle, even when the effects are not as pronounced. The proposed methods in this article are aiming to define two functional outcomes of total hip replacement that are related to wear and rim loading. It is accepted that wear is not only a function of time, but a function of use. Owing to the methods listed in this article, we are able to determine a) the applied force and b) the sliding distance (force pathway) in a subject-specific manner. The computed hip-reaction force angles and the distance to the rim cup are a measurement for cup or rim loading, and occurs in the so-called safe-zones. This method may well give us insight into the biomechanical situation during gait, after receiving total hip replacement, that we need to fully understand the mechanisms acting on a hip joint and to prove a possible increase of functional outcome after receiving total hip replacement. KW - total hip replacement KW - subject-specific musculoskeletal modeling KW - functional outcome KW - force pathways KW - force angles KW - critical hip joint loading KW - rim loading KW - cup loading KW - Hüftgelenkprothese KW - Biomechanik KW - Lastverteilung KW - Ganganalyse KW - Simulation Y1 - 2012 U6 - https://doi.org/10.1177/0954411912447728 VL - 226 IS - 12 SP - 939 EP - 946 ER - TY - CHAP A1 - Palm, Christoph A1 - Lehmann, Thomas M. A1 - Bredno, J. A1 - Neuschaefer-Rube, C. A1 - Klajman, S. A1 - Spitzer, Klaus T1 - Automated Analysis of Stroboscopic Image Sequences by Vibration Profiles T2 - Advances in Quantitative Laryngoscopy, Voice and Speech Research, Procs. 5th International Workshop N2 - A method for automated segmentation of vocal cords in stroboscopic video sequences is presented. In contrast to earlier approaches, the inner and outer contours of the vocal cords are independently delineated. Automatic segmentation of the low contrasted images is carried out by connecting the shape constraint of a point distribution model to a multi-channel regionbased balloon model. This enables us to robustly compute a vibration profile that is used as a new diagnostic tool to visualize several vibration parameters in only one graphic. The vibration profiles are studied in two cases: one physiological vibration and one functional pathology. KW - Vibration Profile KW - Stroboscopic Images KW - Contour Detection KW - Balloon Model KW - Point Distribution Model Y1 - 2001 UR - https://www.researchgate.net/publication/242439073_Automated_Analysis_of_Stroboscopic_Image_Sequences_by_Vibration_Profiles ER - TY - CHAP A1 - Pietrzyk, Uwe A1 - Palm, Christoph A1 - Beyer, Thomas T1 - Investigation of fusion strategies of multi-modality images T2 - IEEE Nuclear Science Symposium Conference Record N2 - Presenting images from different modalities seems to be a trivial task considering the challenges to obtain registered images as a pre-requisite for image fusion. In combined tomographs like PET/CT, image registration is intrinsic. However, informative image fusion mandates careful preparation owing to the large amount of information that is presented to the observer. In complex imaging situations it is required to provide tools that are easy to handle and still powerful enough to help the observer discriminating important details from background patterns. We investigated several options for color tables applied to brain and non-brain images obtained with PET, MRI and CT. KW - Positron emission tomography KW - Biomedical imaging KW - Medical diagnostic imaging KW - Image fusion KW - Computed tomography KW - Image registration KW - Visualization KW - Table lookup KW - Humans Y1 - 2004 U6 - https://doi.org/10.1109/NSSMIC.2004.1462740 VL - 4 SP - 2399 EP - 2401 ER - TY - CHAP A1 - Pietrzyk, Uwe A1 - Bauer, Dagmar A1 - Vieten, Andrea A1 - Bauer, Andreas A1 - Langen, Karl-Josef A1 - Zilles, Karl A1 - Palm, Christoph T1 - Creating consistent 3D multi-modality data sets from autoradiographic and histological images of the rat brain T2 - IEEE Nuclear Science Symposium Conference Record N2 - Volumetric representations of autoradiographic and histological images gain ever more interest as a base to interpret data obtained with /spl mu/-imaging devices like microPET. Beyond supporting spatial orientation within rat brains especially autoradiographic images may serve as a base to quantitatively evaluate the complex uptake patterns of microPET studies with receptor ligands or tumor tracers. They may also serve for the development of rat brain atlases or data models, which can be explored during further image analysis or simulation studies. In all cases a consistent spatial representation of the rat brain, i.e. its anatomy and the corresponding quantitative uptake pattern, is required. This includes both, a restacking of the individual two-dimensional images and the exact registration of the respective volumes. We propose strategies how these volumes can be created in a consistent way and trying to limit the requirements on the circumstances during data acquisition, i.e. being independent from other sources like video imaging of the block face prior to cutting or high resolution micro-X-ray CT or micro MRI. KW - Neoplasms KW - Data models KW - Image analysis KW - Brain modeling KW - Analytical models KW - Anatomy KW - Data acquisition KW - High-resolution imaging KW - Image resolution KW - Computed tomography Y1 - 2004 U6 - https://doi.org/10.1109/NSSMIC.2004.1466754 VL - 6 SP - 4001 EP - 4003 ER - TY - CHAP A1 - Pietrzyk, Uwe A1 - Palm, Christoph A1 - Beyer, Thomas T1 - Fusion strategies in multi-modality imaging T2 - Medical Physics, Vol 2. Proceedings of the jointly held Congresses: ICMP 2005, 14th International Conference of Medical Physics of the International Organization for Medical Physics (IOMP), the European Federation of Organizations in Medical Physics (EFOMP) and the German Society of Medical Physics (DGMP) ; BMT 2005, 39th Annual Congress of the German Society for Biomedical Engineering (DGBMT) within VDE ; 14th - 17th September 2005, Nuremberg, Germany KW - Bildgebendes Verfahren KW - Registrierung Y1 - 2005 SP - 1446 EP - 1447 ER - TY - CHAP A1 - Palm, Christoph A1 - Dehnhardt, Markus A1 - Vieten, Andrea A1 - Pietrzyk, Uwe T1 - 3D rat brain tumor reconstruction T2 - Biomedizinische Technik KW - Dreidimensionale Rekonstruktion KW - Hirntumor Y1 - 2005 VL - 50 IS - Suppl. 1, Part 1 SP - 597 EP - 598 ER - TY - CHAP A1 - Geith, Markus A. A1 - Sommer, Gerhard A1 - Schratzenstaller, Thomas A1 - Holzapfel, Gerhard A. T1 - First Approaches in Quantifying Acute Vascular Damage due to Stenting T2 - 23rd Congress of the European Society of Biomechanics, July 2-5,2017, Seville, Spain KW - Stent KW - Implantation KW - Gefäßverletzung Y1 - 2017 ER - TY - CHAP A1 - Wiesent, Lisa A1 - Geith, Markus A. A1 - Wagner, Marcus T1 - Simulation of Fluid-Structure Interaction between injection medium and balloon catheter using ICFD T2 - 11th European LS-DYNA Conference 2017, 9 - 11 May, Salzburg, Austria N2 - Arteriosclerosis is a major health issue worldwide. While it is commonly treated by the implantation of an balloon-expandable stent, micro injuries may occur during stent deployment, and induce in-stent restenosis, whose consequence can be fatal. Studying this undesirable phenomenon is usually limited as experimental data is hard to obtain on ethical ground. Numerical simulation are performed to better understand this problem. To construct a more realistic simulation of a balloon-expandable stent, a partitioned strongly-coupled FSI simulation of the balloon deployment was set up using the ICFD solver of LS-DYNA, - a quite innovative approach. The complex balloon configuration as well as the interaction of the injection medium and the balloon structure was considered. The balloon structure consisting of shell elements was obtained from preliminary balloon folding and pleating simulations. The balloon consists of a flexible thin walled polyamide. The injection fluid is implemented using volume elements. Balloon deployment was initiated by a pressure boundary condition inducing a volume flow into the balloon. The initial feasibility analysis showed promising result including a continuous balloon deployment and a reasonable development of the fluid pressure and velocity field. However, applying this FSI approach to a more complex balloon structure led to a non convergent solution. The non-convergence could be mainly reduced to mechanical factors including the low wall thickness of the balloon (< 0.05 mm) and the flexibility of the polyamide. Further, the ICFD solver shows less accuracy concerning the FSI conditions when dealing with thin flexible structures as well as enclosed volumes. A shell thickness of 0.06 mm is believed to result in a convergent solution. KW - Koronare Herzkrankheit KW - Stent KW - Ballondilatation KW - Numerische Strömungssimulation Y1 - 2017 UR - https://www.dynalook.com/conferences/11th-european-ls-dyna-conference/icfd-solver-and-fsi/simulation-of-fluid-structure-interaction-between-injection-medium-and-balloon-catheter-using-icfd SN - 978-3981621549 ER - TY - CHAP A1 - Dendorfer, Sebastian A1 - Feldotto, Benedikt A1 - Walch, Blasius A1 - Koch, Patrick A1 - Knoll, Alois T1 - Co-Development of an Infant Prototype in Hardware and Simulation based on CT Imaging Data T2 - IEEE International Conference on Cyborg and Bionic Systems (CBS), 2019, Munich N2 - The development of biomimetic robots has gained research interest in the last years as it may both help under-standing processes of motion execution in biological systems as well as developping a novel generation of intelligent and energy efficient robots. However, exact model generation that builds up on observations and robot design is very time intensive. In this paper we present a novel pipeline for co-development of biomimetic hardware and simulation models based on biological Computer Tomography (CT) data. For this purpose we exploit State of the Art rapid prototyping technologies such as 3D Printing and the Neurorobotics Platform for musculoskeletal simulations in virtual environments. The co-development integrates both advantages of virtual and physical experimental models and is expected to increase development speed of controllers that can be tested on the simulated counterpart before application to a printed robot model. We demonstrate the pipeline by generating a one year old infant model as a musculoskeletal simulation model and a print-in-place 3D printed skeleton as a single movable part. Even though we hereonly introduce the initial body generation and only a first testsetup for a modular sensory and control framework, we can clearly spot advantages in terms of rapid model generation and highly biological related models. Engineering costs are reducedand models can be provided to a wide research community for controller testing in an early development phase. KW - Biomechanische Analyse KW - Robotik KW - Computertomographie KW - 3D-Druck Y1 - 2019 UR - http://mediatum.ub.tum.de/doc/1520042/985669104579.pdf ER - TY - CHAP A1 - Middel, Luise A1 - Palm, Christoph A1 - Erdt, Marius T1 - Synthesis of Medical Images Using GANs T2 - Uncertainty for safe utilization of machine learning in medical imaging and clinical image-based procedures. First International Workshop, UNSURE 2019, and 8th International Workshop, CLIP 2019, held in conjunction with MICCAI 2019, Shenzhen, China, October 17, 2019 N2 - The success of artificial intelligence in medicine is based on the need for large amounts of high quality training data. Sharing of medical image data, however, is often restricted by laws such as doctor-patient confidentiality. Although there are publicly available medical datasets, their quality and quantity are often low. Moreover, datasets are often imbalanced and only represent a fraction of the images generated in hospitals or clinics and can thus usually only be used as training data for specific problems. The introduction of generative adversarial networks (GANs) provides a mean to generate artificial images by training two convolutional networks. This paper proposes a method which uses GANs trained on medical images in order to generate a large number of artificial images that could be used to train other artificial intelligence algorithms. This work is a first step towards alleviating data privacy concerns and being able to publicly share data that still contains a substantial amount of the information in the original private data. The method has been evaluated on several public datasets and quantitative and qualitative tests showing promising results. KW - Neuronale Netze KW - Deep Learning KW - Generative adversarial networks KW - Machine Learning KW - Artificial Intelligence KW - Data privacy KW - Deep Learning KW - Bilderzeugung KW - Datenschutz Y1 - 2019 SN - 978-3-030-32688-3 U6 - https://doi.org/10.1007/978-3-030-32689-0_13 SN - 0302-9743 SP - 125 EP - 134 PB - Springer Nature CY - Cham ER - TY - CHAP A1 - Weiherer, Maximilian A1 - Zorn, Martin A1 - Wittenberg, Thomas A1 - Palm, Christoph ED - Tolxdorff, Thomas ED - Deserno, Thomas M. ED - Handels, Heinz ED - Maier, Andreas ED - Maier-Hein, Klaus H. ED - Palm, Christoph T1 - Retrospective Color Shading Correction for Endoscopic Images T2 - Bildverarbeitung für die Medizin 2020. Algorithmen - Systeme - Anwendungen. Proceedings des Workshops vom 15. bis 17. März 2020 in Berlin N2 - In this paper, we address the problem of retrospective color shading correction. An extension of the established gray-level shading correction algorithm based on signal envelope (SE) estimation to color images is developed using principal color components. Compared to the probably most general shading correction algorithm based on entropy minimization, SE estimation does not need any computationally expensive optimization and thus can be implemented more effciently. We tested our new shading correction scheme on artificial as well as real endoscopic images and observed promising results. Additionally, an indepth analysis of the stop criterion used in the SE estimation algorithm is provided leading to the conclusion that a fixed, user-defined threshold is generally not feasible. Thus, we present new ideas how to develop a non-parametric version of the SE estimation algorithm using entropy. KW - Endoskopie KW - Bildgebendes Verfahren KW - Farbenraum KW - Graustufe Y1 - 2020 SN - 978-3-658-29266-9 U6 - https://doi.org/10.1007/978-3-658-29267-6 SP - 14 EP - 19 PB - Springer Vieweg CY - Wiesbaden ER - TY - CHAP A1 - Chang, Ching-Sheng A1 - Lin, Jin-Fa A1 - Lee, Ming-Ching A1 - Palm, Christoph ED - Tolxdorff, Thomas ED - Deserno, Thomas M. ED - Handels, Heinz ED - Maier, Andreas ED - Maier-Hein, Klaus H. ED - Palm, Christoph T1 - Semantic Lung Segmentation Using Convolutional Neural Networks T2 - Bildverarbeitung für die Medizin 2020. Algorithmen - Systeme - Anwendungen. Proceedings des Workshops vom 15. bis 17. März 2020 in Berlin N2 - Chest X-Ray (CXR) images as part of a non-invasive diagnosis method are commonly used in today’s medical workflow. In traditional methods, physicians usually use their experience to interpret CXR images, however, there is a large interobserver variance. Computer vision may be used as a standard for assisted diagnosis. In this study, we applied an encoder-decoder neural network architecture for automatic lung region detection. We compared a three-class approach (left lung, right lung, background) and a two-class approach (lung, background). The differentiation of left and right lungs as direct result of a semantic segmentation on basis of neural nets rather than post-processing a lung-background segmentation is done here for the first time. Our evaluation was done on the NIH Chest X-ray dataset, from which 1736 images were extracted and manually annotated. We achieved 94:9% mIoU and 92% mIoU as segmentation quality measures for the two-class-model and the three-class-model, respectively. This result is very promising for the segmentation of lung regions having the simultaneous classification of left and right lung in mind. KW - Neuronales Netz KW - Segmentierung KW - Brustkorb KW - Deep Learning KW - Encoder-Decoder Network KW - Chest X-Ray Y1 - 2020 SN - 978-3-658-29266-9 U6 - https://doi.org/10.1007/978-3-658-29267-6_17 SP - 75 EP - 80 PB - Springer Vieweg CY - Wiesbaden ER - TY - CHAP A1 - Souza Jr., Luis Antonio de A1 - Ebigbo, Alanna A1 - Probst, Andreas A1 - Messmann, Helmut A1 - Papa, João Paulo A1 - Mendel, Robert A1 - Palm, Christoph T1 - Barrett's Esophagus Identification Using Color Co-occurrence Matrices T2 - 31st SIBGRAPI Conference on Graphics, Patterns and Images (SIBGRAPI), Parana, 2018 N2 - In this work, we propose the use of single channel Color Co-occurrence Matrices for texture description of Barrett’sEsophagus (BE)and adenocarcinoma images. Further classification using supervised learning techniques, such as Optimum-Path Forest (OPF), Support Vector Machines with Radial Basisunction (SVM-RBF) and Bayesian classifier supports the contextof automatic BE and adenocarcinoma diagnosis. We validated three approaches of classification based on patches, patients and images in two datasets (MICCAI 2015 and Augsburg) using the color-and-texture descriptors and the machine learning techniques. Concerning MICCAI 2015 dataset, the best results were obtained using the blue channel for the descriptors and the supervised OPF for classification purposes in the patch-based approach, with sensitivity nearly to 73% for positive adenocarcinoma identification and specificity close to 77% for BE (non-cancerous) patch classification. Regarding the Augsburg dataset, the most accurate results were also obtained using both OPF classifier and blue channel descriptor for the feature extraction, with sensitivity close to 67% and specificity around to76%. Our work highlights new advances in the related research area and provides a promising technique that combines color and texture information, allied to three different approaches of dataset pre-processing aiming to configure robust scenarios for the classification step. KW - Barrett’s Esophagus KW - Co-occurrence Matrices KW - Machine learning KW - Texture Analysis Y1 - 2018 U6 - https://doi.org/10.1109/SIBGRAPI.2018.00028 SP - 166 EP - 173 ER - TY - CHAP A1 - Fischer, B. A1 - Palm, Christoph A1 - Lehmann, Thomas M. A1 - Spitzer, Klaus T1 - Selektion von Farbtexturmerkmalen zur Tumorklassifikation dermatoskopischer Fotografien T2 - Bildverarbeitung für die Medizin 2002 Y1 - 2002 SP - 238 EP - 241 PB - Springer CY - Berlin ER - TY - CHAP A1 - Dendorfer, Sebastian A1 - Kubowitsch, Simone A1 - Süß, Franz T1 - How to determine the effect of working conditions on the human body T2 - 11th International Scientific Conference on Production Engineering DEVELOPMENT AND MODERNIZATION OF PRODUCTION (RIM 2017), Sarajevo, Bosnia and Herzegovina N2 - Work places and conditions strains the human body, both psychologically and biomechanically. In order to analyse working conditions and in the following to improve them, detailed knowledge about the effect of the different stressors on the body is needed. This manuscript discusses methods on how to evaluate biomechanical and mental loading and its effect on the musculoskeletal system. A possible workflow for the analysis is presented. KW - Arbeitsbedingungen KW - Körper KW - Mensch Y1 - 2017 UR - https://tfb.ba/repozitorij/2/RIM/RIM2017/01A-Sebastian%20Dendorfer,%20Simone%20Kubowitsch,%20Franz%20S%C3%BC%C3%9F-HOW%20TO%20DETERMINE%20THE%20EFFECT%20OF%20WORKING%20CONDITIONS%20ON%20THE%20HUMAN%20BODY.pdf ER - TY - CHAP A1 - Lange, Frederick A1 - Herrmann, Frank A1 - Claus, Thorsten T1 - Simulation based capacity estimation for a model of order release planning under the consideration of service levels T2 - Proceedings of the 15th International Conference on Simulation in Production and Logistics, October 9 - 11, 2013, Paderborn, Germany N2 - Clearing Functions describe the nonlinear relationship between the orders which are in process and the output in capacitated productions systems under high utilization. These Clearing Function can be derived analytical by using steady-state queuing models or empirical by using simulation. We show how to estimate a Clearing Function for a single-level multi-product production system by using a simulation model. This non-linear Clearing Function is integrated into a model of order release planning. We extend this model to consider the uncertainty of the demand by using a Beta service level. We compare our model with an inventory management policy under different demand conditions. KW - Clearing function KW - linear programming KW - order release planning KW - simulation Y1 - 2013 UR - http://www.scs-europe.net/conf/ecms2013/ecms2013proceedings.pdf SN - 978-0-9564944-6-7 SP - 741 EP - 747 ER - TY - CHAP ED - Fuchs, Gerhard ED - Herrmann, Frank ED - Müller, Christian ED - Wirtz, Klaus Werner T1 - Anwendungen und Techniken zur Analyse großer Datenbestände BT - Tagungsband zur AKWI-Fachtagung am 11. bis 12.09.2008 an der Hochschule Niederrhein ; [Beiträge der Fachtagung "Anwendungen und Techniken zur Analyse Großer Datenbestände" im Rahmen der 21. Jahrestagung des Arbeitskreises Wirtschaftsinformatik an Fachhochschulen (AKWI)] N2 - Mit dem Vorliegen großer Datenbestände steigen natürlich auch die Wünsche und Anforderungen zur Analyse dieser Daten. Aus diesen Gründen widmet sich die AKWI Tagung 2008 mit den hier dokumentierten Beiträgen und Diskussionen diesem Thema unter dem Titel: Herausforderungen an die Wirtschaftsinformatik: Anwendungen und Techniken zur Analyse großer Datenbestände. Mit dem analytischen Customer Relationship Management (CRM) wird von Frick und Iversen das Ziel verfolgt, die Analyse der verfügbaren Informationen für die Kundenbedürfnisse einzusetzen. Das kann beträchtlich die Qualität der Kundenbeziehungen verbessern. Es erfordert aber auch eine Weiterqualifizierung aller Beteiligten. Das Supply Chain Management (SCM) dient zur Unternehmensübergreifenden Betrachtung und Modifikation der Geschäftsprozesse. Die ständige Weiterentwicklung der Geschäftsprozesse in den Unternehmen erfordert auch permanent Anpassung bei den davon in der Supply Chain betroffenen Unternehmen. Die Erweiterung der klassischen Sichtweise der Kostenfunktion im Rahmen der Produktionsplanung um die Einfuhrzollproblematik wird von Szymanski mit einem Ansatz zur Optimierung der Supply Chain mit mathematischen Optimierungsmodellen aufgezeigt. Die Gründe dafür liegen in den immer globaleren Gegebenheiten der Beschaffungs-, Produktions- und Distributionslogistik. Für die umfangreichen Aufgaben im Umgang mit den Enterprise Ressource Planning (ERP) Systemen und deren Implementierung werden heute entsprechende Tools benötigt. Von SAP wird dafür der SAP Solution Manager angeboten. Von Frick und Lankes wird der SAP Solution Manager als ein Projektmanagement Werkzeug eingesetzt. Unternehmen jeder Größenordnung sehen sich zunehmend mit der Herausforderung konfrontiert, die betrieblichen Daten für die unterschiedlichsten Zielsetzungen zur Verfügung zu stellen. Neben den betrieblichen Anforderungen rücken hier aber auch die Änderung der Abgabenordnung (AO) und damit der Datenzugriff durch die Finanzbehörden, die Einhaltung von Compliance Richtlinien und damit das Erkennen von Unterschlagungshandlungen als auch die Bestätigung der Ordnungsmäßigkeit des Jahresabschlusses durch die Wirtschaftsprüfer immer stärker in den Fokus der digitalen Aufbereitung von Unternehmensdaten. Wirtschaftsprüfer, Interne Revisoren und Betriebsprüfer der Finanzverwaltung haben die gleichen Probleme zu bewältigen, indem sie sich mit einer gewachsenen, heterogenen und durch Firmenzukäufe und Ausgliederungen stetig ändernden IT Infrastruktur auseinander zu setzen haben. Von Herde wird ein Ansatz zur Extraktion betrieblicher Massendaten in ein analysefähiges Format, unabhängig von operativen Systemen, kostengünstig realisiert. Der Umgang mit großen Mengen von Daten, auch aus unterschiedlichen Unternehmensbereichen, einer großen Anzahl von Benutzern erfordert heute ein Data Warehouse mit konsolidierten Daten. Ohne eine ausreichende Konsolidierung, d. h. ohne eine einheitliche Darstellung der Daten, kann keine sinnvolle Auswertung erfolgen. Erst mit einem Data Warehouse können die Mitarbeiter auch erkennen, was das Unternehmen zu speziellen Fragen eigentlich alles weiß. Von Stegemerten wird aufgezeigt, wie aus einer bestehenden Unternehmensstrategie eine Strategie zum Aufbau eines Data Warehouses abgeleitet werden kann und eine Organisationsstruktur beschrieben, die diese Umsetzung gewährleistet. Die Bedeutung des Controllings wird in dem Beitrag von Frank Weymerich mit der Entwicklung eines entsprechenden Cockpits deutlich. Hier werden die für das Controlling nützlichen Informationen in einem individuell bedienbaren Cockpit für die betrieblichen Entscheider sinnvoll zusammengestellt. In allen Beiträgen werden unterschiedliche spezielle Aspekte der Analyse und Organisation großer Datenbestände aus der Sicht der Wirtschaftsinformatik mit dem ihr eigenen Blick auf die Gesamtheit aller Einflussgrößen aufgezeigt. KW - Controlling KW - Customer Relationship Management KW - Data Warehouse KW - SAP Solution Manager KW - Supply Chain Management KW - Business Computing KW - CRM Y1 - 2008 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-2489 PB - Verlag News & Media CY - Berlin ER - TY - CHAP A1 - Herrmann, Frank T1 - Simulated Determination and Usage of a Clearing Function for Leadtime Estimation T2 - Proceedings of the 27th EURO Conference on Operations Research, July 13 - 18, 2014, Barcelona, Spain KW - clearing functions KW - lead time estimation Y1 - 2014 ER - TY - CHAP A1 - Amann, Matthias A1 - Herrmann, Frank A1 - Lutz, Christian A1 - Meier, Markus ED - Barton, Thomas ED - Erdlenbruch, Burkhard ED - Herrmann, Frank ED - Müller, Christian T1 - Grad der Zerstörung für eine lokale Suche bei einer taktgetriebenen Fließfertigung T2 - Prozesse, Technologien, Anwendungen, Systeme und Management. Angewandte Forschung in der Wirtschaftsinformatik. Tagungsband zur 27. AKWI-Fachtagung vom 07. bis 10.09.2014 an der Oberbayerischen Technischen Hochschule Regensburg N2 - Unternehmen produzieren oftmals viele Varianten für ein kleines Kundensegment und in kleinen Stückzahlen auf sehr teuren Produktionsanlagen. Deren effiziente und effektive Nutzung erfordert eine möglichst gute Planung der Belegung der Stationen mit Aufträgen. Sehr wirkungsvoll bei Fertigungslinien sind lokale Suchverfahren. Sie erzielen ein lokales Optimum. Um ein globales Optimum zu erreichen, wird die Suche von einem anderen Punkt des Suchraums fortgesetzt. Dabei sollte kein willkürlicher Punkt gewählt werden, sondern nur ein Teil des lokalen Optimums zerstört werden. Unterschiedlich starke Zerstörungen werden für eine taktgetriebene Fließfertigung analysiert. KW - Fließvertigung KW - Fertigungsplanung KW - Optimierung Y1 - 2014 UR - http://www.akwi.de/documents/AKWI_Tagungsband2014.pdf SP - 44 EP - 54 PB - Verlag News & Media CY - Berlin ER - TY - CHAP A1 - Englberger, Julian A1 - Herrmann, Frank A1 - Claus, Thorsten T1 - Independent Requirements Consumption in Master Production Scheduling in an Uncapacitated Environment T2 - Informatics, Microsystems, Information Systems. Proceedings. 2012 KW - Produktionsplanung KW - Kundenorientierung Y1 - 2012 SN - 9785733909301 VL - Vol. 1(1) ER - TY - CHAP A1 - Englberger, Julian A1 - Herrmann, Frank T1 - Estimating Capacity Load Factors in Master Production Scheduling by the use of Stochastic Optimization T2 - Tagungsband zu der Tagung Logistikmanagement 2013, 10. - 13. Oktober 2013, Bremen, Deutschland KW - Produktionsplanung KW - Ablaufplanung KW - Kapazitätsplanung KW - Stochastische Optimierung Y1 - 2013 ER - TY - CHAP A1 - Frank, Ingo A1 - Herrmann, Frank A1 - Claus, Thorsten T1 - Improving sustainability through substitutes in cross-location production planning T2 - Proceedings of the International Annual Conference of the German Operations Research Society 2019 (OR 2019), Dresden, September 3 - 6, 2019 KW - Produktionsplanung KW - Standortverlagerung KW - Nachhaltigkeit Y1 - 2019 ER - TY - CHAP A1 - Palm, Christoph A1 - Vieten, Andrea A1 - Bauer, Dagmar A1 - Pietrzyk, Uwe T1 - Evaluierung von Registrierungsstrategien zur multimodalen 3D-Rekonstruktion von Rattenhirnschnitten T2 - Bildverarbeitung für die Medizin 2006 N2 - In dieser Arbeit werden drei Strategien zur 3D Stapelung von multimodalen Schnittbildern vorgestellt. Die Strategien werden experimentell anhand von Dualtracer-Autoradiographien evaluiert. Dazu werden neue Maße zur Beschreibung der Konsistenz innerhalb einer Modalität und der Konsistenz der Modalitäten untereinander entwickelt, die auf bekannten Registrierungsmetriken basieren. Gerade bezüglich der Konsistenz der Modalitäten untereinander zeigen zwei Strategien die besten Resultate: (1) abwechselnde multimodale Registrierung (2) monomodale Rekonstruktion einer Modalität und multimodale 2D Registrierung der zweiten Modalität. KW - Registrierung KW - Dreidimensionale Rekonstruktion KW - Gehirn KW - Schnittpräparat Y1 - 2006 U6 - https://doi.org/10.1007/3-540-32137-3_51 SP - 251 EP - 255 PB - Springer CY - Berlin ER - TY - CHAP A1 - Englberger, Julian A1 - Herrmann, Frank A1 - Claus, Thorsten T1 - Simulation of robust Master Production Scheduling in an industrially relevant planning environment T2 - Proceedings of the 27th EUROPEAN Conference on Modeling and Simulationn, May 27th - 30th, 2013, Ålesund, Norway N2 - This paper presents a simulation analysis on the effects of robust master production scheduling. Up to now, relatively highly aggregated planning models for robust master production scheduling were regarded and the realizability of the planning results was not considered. This paper analyses a more detailed model for master production scheduling than in previous works. The evaluation of the planning results is made by providing the planning results to the subsequent planning levels in a hierarchical production planning system and realizing them in a realistic production system. The primary objective of the production system is to minimise tardiness of customer order deliveries. The secondary objective is to minimise inventory of end products. It is shown that robust master production scheduling in such a planning system leads to significant reductions of tardiness of customer order shipment. Compared to an equivalent deterministic approach for master production scheduling, the mean customer order backlog is reduced more than the mean inventory levels are increased. KW - Hierarchische Produktionsplanung KW - Auftragsabwicklung KW - Optimierung KW - robust optimisation KW - production planning KW - simulation Y1 - 2013 U6 - https://doi.org/10.7148/2013-0794 SP - 794 EP - 800 ER - TY - CHAP A1 - Herrmann, Frank T1 - Simulation of the control of exponential smoothing by methods used in industrial practice T2 - Proceedings of the 26th EUROPEAN Conference on Modeling and Simulation, May 29th - June 1st, 2012, Koblenz, Germany N2 - Demands of customers for products and of the production for parts are being forecasted quite often in companies. The results are used extensively within the operational production planning and control by IT Systems like the SAP system. Hereby preferably methods based on exponential smoothing are being applied. Especially, in industrial practice it is expected that the pattern of the data change over time in such a way, that the parameters of the exponential smoothing have to be changed. In some companies thousands of items require forecasting, which is very laborious. With an adaptive method the parameters are modified in a controlled manner, as changes in the pattern occur. Two adaptive methods used in industrial practice are explained. Simulation experiments over a huge number of periods show when they should be used. KW - PPS KW - Nachfrage KW - Prognose KW - Exponentielle Glättung KW - forecast of demands in industrial practice KW - Simulation experiment KW - Enterprise Resource Planning (ERP) system KW - Production Planning and Control (PPS) system, KW - Adaptive method KW - Exponential smoothing Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-2262 ER - TY - CHAP A1 - Englberger, Julian A1 - Herrmann, Frank A1 - Claus, Thorsten T1 - Simulation-based determination of capacity load factors for master production scheduling T2 - Proceedings of the 15th International Conference on Simulation in Production and Logistics, October 9 - 11, 2013, Paderborn, Germany N2 - This paper deals with the problem of varying capacity load factors in master production scheduling. A simulation system of a production planning and control system and of a production system is described and an approach to compute the capacity loads from the simulation results is developed. This approach is used to measure period-specific capacity load factors for master production scheduling. The measured capacity load factors vary over time and show that the common assumption of the load factors being period-independent is inappropriate. A stochastic programming model to cope with this variation is described. This model is compared to a common linear programming model for master production scheduling in a simulation experiment. The results show that the use of the measured capacity load factor scenarios improves the quality of the estimation of the capacity load factors significantly. KW - PPS KW - Kapazitätsplanung KW - Stochastisches Modell Y1 - 2013 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-2610 SP - 631 EP - 640 ER - TY - CHAP A1 - Herrmann, Frank T1 - Simulative analysis of storage strategies for pallet warehouses T2 - Informatics, Microsystems, Information System, Proceedings, 2012 KW - Palette KW - Lagerhaltung KW - Strategisches Management KW - Simulation Y1 - 2012 VL - Vol. 1(1) ER - TY - CHAP A1 - Lange, Frederick A1 - Herrmann, Frank T1 - Verbesserung der operativen Produktionsplanung durch Belastungsinformationen T2 - Tagungsband der 7. Wismarer Wirtschaftsinformatik-Tage, Wismar, 2012 KW - Produktionsplanung KW - Operative Planung KW - Belastungsorientierte Fertigungssteuerung Y1 - 2012 ER - TY - CHAP A1 - Davendra, Donald A1 - Herrmann, Frank A1 - Bialic-Davendra, Magdalena T1 - Scheduling tardiness constrained flow shop with simultaneously loaded stations using Genetic Algorithm T2 - Proceedings of the 4th International Conference on Intelligent Systems, Metaheuristics & Swarm Intelligence (ISMSI 2020): Thimphu, Kingdom of Bhutan during March 21-22, 2020 N2 - In this study, a real world flow shop with a transportation restriction is regarded. This restriction reduces the set of feasible schedules even more than the no-buffer restrictions discussed in the literature in the case of limited storage. Still this problem is NP-hard. Since this scheduling problem is integrated in the usual hierarchical planning, the tardiness is minimised. Compared to even specific priority rule for this class of problems the suggested genetic algorithm delivers significant better results. The specific structure of this class of problems complicates the calculation of the performance criteria. This is solved by a simulation algorithm. KW - simulation of restrictions KW - scheduling, KW - flow-shop KW - no-buffer (blocking) KW - no-wait KW - genetic algorithm KW - real world application KW - Ablaufplanung KW - Hierarchische Produktionsplanung KW - Flow-shop-Problem KW - Reihenfolgeproblem KW - Genetischer Algorithmus Y1 - 2020 U6 - https://doi.org/10.1145/3396474.3396475 PB - ACM ER - TY - CHAP A1 - Herrmann, Frank A1 - Stumvoll, Ulrike T1 - Überwachung und Verbesserung von Losgrößenmodifikatoren eines PPS-Systems im laufenden Betrieb T2 - Proceedings zur 14. ASIM Fachtagung "Simulation in Produktion und Logistik" vom 6. bis 8. Oktober 2010 am Karlsruher Institut für Technologie, Karlsruhe KW - PPS KW - Losgrößenplanung Y1 - 2010 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-2435 SP - 45 EP - 65 ER - TY - CHAP A1 - Herrmann, Frank ED - Barton, Thomas ED - Erdlenbruch, Burkhard ED - Herrmann, Frank ED - Müller, Christian ED - Schuler, Joachim T1 - Unterstützung einer selbststeuernden Planung durch eine geeignete Erweiterung des SAP Systems. T2 - Management und IT. Tagungsband zur AKWI-Fachtagung am 16.9.2012 an der Hochschule Pforzheim (FH) KW - Enterprise-Resource-Planning KW - PPS KW - Auftragsabwicklung KW - SAP R/3 Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-2231 SP - 65 EP - 76 PB - News & Media CY - Berlin ER - TY - CHAP A1 - Lange, Frederick A1 - Herrmann, Frank A1 - Claus, Thorsten T1 - Simulation based clearing functions for a model of order release planning T2 - Proceedings of the 27th EUROPEAN Conference on Modeling and Simulation, May 27th - 30th, 2013, Ålesund, Norway N2 - In capacitated production systems at high utilization there exists a nonlinear relationship between the orders which are in process and the output. This nonlinear relationship can be described by nonlinear Clearing Functions. We show how a Clearing function will be estimated and integrate it into a model of order releases planning. We compare our model with two inventory management policies under different demand conditions. KW - clearing function KW - linear programming KW - order release planning KW - simulation KW - Auftragsabwicklung KW - Clearing function Y1 - 2013 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-2205 SP - 741 EP - 747 ER - TY - CHAP A1 - Herrmann, Frank T1 - Simulation based priority rules for scheduling of a flow shop with simultaneously loaded stations T2 - Proceedings of the 27th EUROPEAN Conference on Modeling and Simulation, May 27th - 30th, 2013, Ålesund, Norway N2 - In this study, a real world flow shop with a transportation restriction is regarded. This restriction reduces the set of feasible schedules even more than the no-buffer restrictions discussed in the literature in the case of limited storage. Since this scheduling problem is integrated in the usual hierarchical planning, the tardiness is minimised. This NP-hard problem is solved by priority rules, because of the addressed dynamic environment (and a high number of jobs) at the company site. Due to the technological restrictions the real duration of a job is significantly larger than its net processing time. By a simulation of the processing time many priority rules are improved and some even significantly. With extensive simulations successful priority rules in the literature are analysed. KW - simulation of processing time KW - scheduling KW - flow-shop KW - no-buffer (blocking) KW - no-wait KW - priority rules KW - real world application KW - Hierarchische Produktionsplanung KW - Flow-shop-Problem KW - Reihenfolgeproblem Y1 - 2013 U6 - https://doi.org/10.7148/2013-0775 SP - 775 EP - 781 ER - TY - CHAP A1 - Herrmann, Frank T1 - Observations to Clearing Functions T2 - Proceedings of the 28th EURO Conference on Operations Research, July 12 - 15, 2015, Glasgow, Scotland KW - clearing functions Y1 - 2015 ER - TY - CHAP A1 - Selmair, Maximilian A1 - Herrmann, Frank A1 - Claus, Thorsten A1 - Teich, Enrico T1 - Potential of Reducing the Total Energy Consumption by Scheduling a Jobshop Production System T2 - Proceedings of the 16th International Conference on Simulation in Production and Logistics, September 23 - 25, 2015, Dortmund, Germany N2 - This research paper has evaluated the potential of reducing energy consumption by scheduling jobshop production systems with machines using standby modes in free times. The initial introduction of the planning issue is followed by a description of the approach to assess the available potential. Subsequently, the research procedure by means of simulation, a detailed discussion of the results and a perspective on future research is given. Moreover, the notion that scheduling influences the energy consumption in jobshop production systems is supported. The presented simulation research also documents that there is no direct correlation between energy consumption and total lead time, although this was presumed usually. Finally, this paper provides a forecast for a possible optimisation model as well as an exemplary model with an energy-optimised schedule plan. KW - Produktionsplanung KW - Reihenfolgeproblem KW - Energieverbrauch Y1 - 2015 SP - 375 EP - 384 ER - TY - CHAP A1 - Manitz, Michael A1 - Herrmann, Frank A1 - Munninger, Maximilian T1 - Considering sequence-dependent stochasticity in production schedules T2 - Proceedings of the International Annual Conference of the German Operations Research Society 2017 (OR 2017), Berlin, September 6 - 8, 2017 KW - Produktionsplanung KW - Ablaufplanung KW - Reihenfolgeproblem KW - Stochastischer Prozess Y1 - 2017 ER - TY - CHAP A1 - Trost, Marco A1 - Claus, Thorsten A1 - Herrmann, Frank T1 - Master production scheduling with consideration of social aspects for networking with human resources requirements planning T2 - Proceedings of the International Annual Conference of the German Operations Research Society 2018 (OR 2018), Brüssel, September 12 - 14, 2018 N2 - A large number of current research focuses on the sustainable orientation of business processes. However, it is often neglected that, next to the ecological and economic dimension, the social dimension is also an important pillar of sustainability. Therefore, the intended contribution focuses on the integration of social aspects into the Master Production Scheduling and thus achieves a network between production planning and human resources requirements planning. The study shows that previous papers on production planning and control usually ignore the social dimension. Exceptions are works that take advantage of learning and forgetting effects at the lot-sizing and scheduling. In addition, there are various papers in the scheduling area which aim to reduce employee workload by optimizing resource allocation. Thus, however, only an optimal distribution of burden is achieved. Therefore, this paper presents a long-term management of the burden. To this end, the classic Master Production Scheduling, which has been statically limited in terms of capacity, whereby additional capacities have been used, will be expanded. At the same time, human resources requirements planning is based on assumptions regarding the expected capacity requirements. The created linear optimization model, addresses these weak points. A flexible available capacity is integrated on the basis of existing sales orders. It is making possible, to build up and reduce capacities, whereby technical restrictions (number of workplaces) and labor market conditions (number of available employees, qualification of employees and experience of employees) are also mapped. This represents a significant progress compared to previous models, whereby the target function minimizes costs. Further progress has been made in investigating the effects of exhaustion. The ratio of capacity requirements to available capacity was controlled externally as employee utilization and processing times dependent on the employee's utilization were taken into account. Subsequently, different utilization situations were examined under the assumption of different exhaustion and random demand patterns with the aim of determining an optimal employee utilization. A key finding of this study is that - contrary to common assumptions - achieving cost benefits is not necessarily associated with maximizing utilization, but rather with controlling employee utilization. An additional effect results from the reduction of the employee burden. However, the flexible capacity available does not limit the performance of the production system. In addition, we are currently working on the investigation of effects in a long-term planning horizon and of consequences for the downstream planning levels of production planning and control. Overall, the contribution presents an innovative research project that aims to integrate social aspects into production planning in order to make a contribution to truly sustainable models in the future. KW - Produktionsplanung KW - Ablaufplanung KW - Soziale Verantwortung Y1 - 2018 ER - TY - CHAP A1 - Herrmann, Frank A1 - Lange, Frederick A1 - Manitz, Michael T1 - Order release within hierarchical production planning and control using product specific clearing functions T2 - Proceedings of the International Annual Conference of the German Operations Research Society 2014 (OR 2014), Aachen, September 2 - 5, 2014, Germany KW - Hierarchische Produktionsplanung KW - Auftragsabwicklung KW - clearing functions Y1 - 2014 ER - TY - CHAP A1 - Herrmann, Frank A1 - Lange, Frederick A1 - Almeder, Christian T1 - Capacity estimation based on clearing functions for the capacitated lot-sizing problem T2 - Proceedings of the 5th International Workshop on Lot-Sizing, August 26th - 29th, 2014, Porto, Portugal N2 - Single-stage capacitated lot-sizing problems (CLSP) are essential for manyplanning tasks in production systems. Due to the hierarchical planning approach, which is widely used in industrial practice and implemented in commercial enterprise resource planning as well as production planning and controlsystems, a subsequent scheduling is necessary to gain executable productionplans. Capacity consumption depends on many factors as, for example, systems workload, machine availability, or yield. Thus, a feasible and optimalsolution of the CLSP may lead to unplanned delays after sequencing and processing the orders on the shop floor. Using a so called clearing function (CF),which represents the relationship between the workload and the output of a production system, this capacity consumption in a CLSP is improved in various ways and tested on a real-world application. KW - Hierarchische Produktionsplanung KW - Kapazitätsplanung KW - Losgröße KW - clearing functions Y1 - 2014 UR - https://www.emse.fr/~absi/IWLS2014/proceedings_IWLS_2014.pdf ER - TY - CHAP A1 - Herrmann, Frank T1 - Genetic algorithm with simulation for scheduling of a flow shop with simultaneously loaded stations T2 - Proceedings of the 28th EUROPEAN Conference on Modeling and Simulation, May 27th - 30th, 2014, Brescia, Italy N2 - In this study, a real world flow shop with a transportation restriction is regarded. This restriction reduces the set of feasible schedules even more than the no-buffer restrictions discussed in the literature in the case of limited storage. Still this problem is NP-hard. Since this scheduling problem is integrated in the usual hierarchical planning, the tardiness is minimised. Compared to even specific priority rule for this class of problems the suggested genetic algorithm delivers significant better results. The specific structure of this class of problems complicates the calculation of the performance criteria. This is solved by a simulation algorithm. Proceedings 28th European Conference on Modelling and Simulation. KW - Ablaufplanung KW - Hierarchische Produktionsplanung KW - Flow-shop-Problem KW - Reihenfolgeproblem KW - Genetischer Algorithmus KW - simulation of restrictions KW - scheduling KW - flow-shop KW - no-buffer (blocking) KW - no-wait KW - genetic algorithm KW - real world application Y1 - 2014 UR - http://www.scs-europe.net/dlib/2014/ecms14papers/simo_ECMS2014_0076.pdf ER - TY - CHAP A1 - Claus, Thorsten A1 - Herrmann, Frank T1 - Simulation als betriebliche Entscheidungshilfe T2 - Ergänzungsband zu den Proceedings zur 14. ASIM Fachtagung "Simulation in Produktion und Logistik", vom 6. bis 8. Oktober 2010 am Karlsruher Institut für Technologie, Karlsruhe KW - Produktion KW - Logistik KW - Simulation KW - Entscheidungsprozess Y1 - 2010 ER - TY - CHAP A1 - Herrmann, Frank T1 - Scheduling a flow-shop with simultaneously loaded stations T2 - Proceedings of the International Annual Conference of the German Operations Research Society 2012,(OR 2012), September 4 - 7, Hannover KW - Fließfertigung KW - Flow-shop-Problem KW - Reihenfolgeproblem Y1 - 2012 ER - TY - CHAP A1 - Herrmann, Frank T1 - Scheduling in case of a Partially Automated Production T2 - Proceedings of the International Annual Conference of the German Operations Research Society 2016 (OR 2016), Hamburg, 30.8. - 4.9.2016 N2 - In recent years, a considerable amount of interest has arisen for scheduling problems with technological restrictions. For example, no-buffer flow-shop scheduling problem are well investigated. Here a real world flow shop with a transportation restriction is regarded. It has to produce small batches, very often with a lot size of one, with short response times. Thus, scheduling algorithms are needed to ensure that under the constraint of a high average load of the flow shop, the duedates of the production orders are met. This transportation restriction reduces the set of feasible schedules even more than the nobuffer restrictions discussed in the literature in the case of limited storage. Still this problem is NP-hard. Due to the transportation restriction, the duration of a job A on the flow-shop depends on the other jobs processedon the flow-shop in the same time frame which is called a cycle. Realistic processing times are achieved by a simulation of the scheduling of A which includes the next jobs until A has left the flow-shop. The usage of such realistic processing times instead of net processing times improves the priority rules by around 16%. There are pools of jobs where a large variance of the cycle times is beneficial and pools of jobs where a small variance is better. This is partially detected by agenetic algorithm. This improves the performance by another 34%. KW - Produktionsplanung KW - Ablaufplanung Y1 - 2016 ER -