@article{SallumAlvesThielemannetal.2024, author = {Sallum, Loriz Francisco and Alves, Caroline and Thielemann, Christiane and Rodrigues, Francisco A.}, title = {Revealing patterns in major depressive disorder with machine learning and networks}, series = {medrxiv}, volume = {2024}, journal = {medrxiv}, number = {1}, doi = {doi.org/10.1101/2024.06.07.24308619}, pages = {1 -- 17}, year = {2024}, abstract = {Major depressive disorder (MDD) is a multifaceted condition that affects millions of people worldwide and is a leading cause of disability. There is an urgent need for an automated and objective method to detect MDD due to the limitations of traditional diagnostic approaches. In this paper, we propose a methodology based on machine and deep learning to classify patients with MDD and identify altered functional connectivity patterns from EEG data. We compare several connectivity metrics and machine learning algorithms. Complex network measures are used to identify structural brain abnormalities in MDD. Using Spearman correlation for network construction and the SVM classifier, we verify that it is possible to identify MDD patients with high accuracy, exceeding literature results. The SHAP (SHAPley Additive Explanations) summary plot highlights the importance of C4-F8 connections and also reveals dysfunction in certain brain areas and hyperconnectivity in others. Despite the lower performance of the complex network measures for the classification problem, assortativity was found to be a promising biomarker. Our findings suggest that understanding and diagnosing MDD may be aided by the use of machine learning methods and complex networks.}, subject = {Depression}, language = {en} } @article{SzewczykMoniciThielemann2024, author = {Szewczyk, Nathaniel J. and Monici, Monica and Thielemann, Christiane}, title = {How to obtain an integrated picture of the molecular networks involved in adaptation to microgravity in different biological systems?}, series = {npj Microgravity}, volume = {2024}, journal = {npj Microgravity}, number = {10}, doi = {DOI: 10.1038/s41526-024-00395-3}, pages = {1 -- 5}, year = {2024}, abstract = {Periodically, the European Space Agency (ESA) updates scientific roadmaps in consultation with the scientific community. The ESA SciSpacE Science Community White Paper (SSCWP) 9, "Biology in Space and Analogue Environments", focusses in 5 main topic areas, aiming to address key community-identified knowledge gaps in Space Biology. Here we present one of the identified topic areas, which is also an unanswered question of life science research in Space: "How to Obtain an Integrated Picture of the Molecular Networks Involved in Adaptation to Microgravity in Different Biological Systems?" The manuscript reports the main gaps of knowledge which have been identified by the community in the above topic area as well as the approach the community indicates to address the gaps not yet bridged. Moreover, the relevance that these research activities might have for the space exploration programs and also for application in industrial and technological fields on Earth is briefly discussed.}, subject = {Weltraumforschung}, language = {en} } @book{Lauer, author = {Lauer, Thomas}, title = {Change Management: Grundlagen und Erfolgsfaktoren}, edition = {3., vollst{\"a}ndig {\"u}berarbeitete und erweiterte Auflage}, publisher = {Springer Gabler}, address = {Berlin}, isbn = {978-3-662-59101-7}, doi = {10.1007/978-3-662-59102-4}, subject = {Change Management}, language = {de} } @techreport{JostMink2024, type = {Working Paper}, author = {Jost, Thomas and Mink, Reimund}, title = {Central bank losses and commercial bank profits - unexpected and unfair?}, series = {IMFS Working Paper Series No. 199}, journal = {IMFS Working Paper Series No. 199}, pages = {35}, year = {2024}, abstract = {The Eurosystem and the Deutsche Bundesbank will incur substantial losses in 2023 that are likely to persist for several years. Due to the massive purchases of securities in the last 10 years, especially of government bonds, the banks' excess reserves have risen sharply. The resulting high interest payments to the banks since the turnaround in monetary poli-cy, with little income for the large-scale securities holdings, led to massive criticism. The banks were said to be making "unfair" profits as a result, while the fiscal authorities had to forego the previously customary transfers of central bank profits. Populist demands to limit bank profits by, for example, drastically increasing the minimum reserve ratios in the Eurosystem to reduce excess reserves are creating new severe problems and are neither justified nor helpful. Ultimately, the EU member states have benefited for a very long time from historically low interest rates because of the Eurosystem's extraordinary loose monetary policy and must now bear the flip side consequences of the massive expansion of central bank balance sheets during the necessary period of monetary policy normalisa-tion.}, subject = {Notenbank}, language = {en} } @misc{JostMink2024, author = {Jost, Thomas and Mink, Reimund}, title = {How to deal with the negative effects of inflated central bank balance sheets?}, organization = {SUERF}, pages = {1 -- 4}, year = {2024}, abstract = {Due to the massive purchases of securities in the last 15 years central banks incur substantial losses likely to persist for several years. On the other hand, the banking sector gains large profits from interest payments on their excess reserves holdings. Central banks and fiscal authorities must now bear the flip side consequences of their bond purchase programs. Populist demands to limit bank profits by drastically increasing minimum reserve ratios in the Eurosystem are creating new severe problems. Instead, a consistent and faster normalisation of central bank balance sheets would be desirable. Central banks should also no longer be central players in government bond markets to restore the lost boundaries between fiscal and monetary policy.}, subject = {Europ{\"a}ische Zentralbank}, language = {en} } @book{HofmannScheidler2024, author = {Hofmann, Georg Rainer and Scheidler, Percy}, title = {Chief Qualification Officer (CQO) und Weiterbildungsmentoren}, isbn = {978-3-9826305-0-2}, pages = {32}, year = {2024}, abstract = {Alte Weisheiten wie „Schuster bleib bei deinem Leisten!" oder auch „Was das H{\"a}nschen nicht lernt, das lernt der Hans nimmermehr" haben in der heutigen, sich wandelnden Arbeitswelt ihren Sinn verloren. Das bedeutet, dass sich die komplette Belegschaft lebenslang weiterbilden muss, idealerweise mit Unterst{\"u}tzung des Arbeitgebers. In der Ver{\"o}ffentlichung "Chief Qualification Officers (CQOs) und Weiterbildungsmentoren - Thesen und Argumente" wird unter anderem das paradoxe Verh{\"a}ltnis von Arbeitslosigkeit und Fachkr{\"a}ftemangel erl{\"a}utert, das Marktversagen im Weiterbildungsmarkt beschrieben und die Forderung nach einem Weiterbildungsbeauftragten (CQO) begr{\"u}ndet.}, subject = {Weiterbildung}, language = {de} } @inproceedings{SmeetsRoetzel2024, author = {Smeets, Mario and R{\"o}tzel, Peter}, title = {The Moderating Role of Non-Monetary Gamification in Reducing Algorithm Aversion in the Adoption of AI-based Decision Support Systems}, series = {ECIS - European Conference on Information Systems}, volume = {2024}, booktitle = {ECIS - European Conference on Information Systems}, number = {1}, pages = {1}, year = {2024}, abstract = {Integrating artificial intelligence (AI) into decision-making processes is key to improving organizational performance. However, trust in AI-based decision support systems (DSSs), similar to other information systems, is important for successful integration. A disruptive phenomenon, "algorithm aversion", can impede AI trust and, thus, acceptance. Although AI recommendations outperform human recommendations in different decision-making fields, individuals underweight recommendations from AI-based DSSs compared to human decision-makers due to a lack of AI trust. We conducted a lab experiment to investigate the role of AI recommendations in workplace-related tasks, first focusing on the mediating effect of AI trust and the negative impact of algorithm aversion on decision-making performance and the moderating effect of technical competence. Second, we analyzed the ability of gamification to reduce this phenomenon. We provide evidence regarding how to enhance decision-making performance when AI recommendations are deployed and identify countermeasures against algorithm aversion to facilitate the adoption of AI-based DSSs.}, subject = {K{\"u}nstliche Intelligenz}, language = {en} } @inproceedings{SauerHoppeBruhm2024, author = {Sauer, Jonas and Hoppe, Florian and Bruhm, Hartmut}, title = {Modellierung des Antriebsstrangs einer Textilmaschine zum Zweck der modellbasierten Steuerung}, series = {Tagungsband AALE 2024, 20. Konferenz}, volume = {2024}, booktitle = {Tagungsband AALE 2024, 20. Konferenz}, doi = {https://doi.org/10.33968/2024.33}, year = {2024}, abstract = {Zur Produktion von gewirkten Textilien werden mehrere Nadeln auf eine Legebarre gesetzt, die durch Servoantriebe positioniert werden. Aufgrund der erzwungenen Bewegung kann der Antriebsstrang bei hohen Drehzahlen zur Schwingung angeregt werden. Die richtige Wahl der Steuerkurven ist daher eine sehr wichtige und anspruchsvolle Aufgabe, die durch ein Antriebsstrangmodell unterst{\"u}tzt werden soll. Daf{\"u}r wird am Beispiel eines Teststands ein Modell des Antriebsstranges in MATLAB/Simulink® entwickelt. F{\"u}r das Antriebsstrangmodell m{\"u}ssen eine geeignete Modellordnung und Modellparameter gew{\"a}hlt werden. Die unbekannten Modellparameter werden durch eine Parameteridentifikation ermittelt. Mit einer Validierung wird ein geeignetes Anregungsspektrum f{\"u}r die Bestimmung der Modellordnung und die Parameteridentifikation ermittelt.}, subject = {Textilmaschine}, language = {de} } @book{LeimeisterSchumacherWenderoth2023, author = {Leimeister, Katja and Schumacher, Meike and Wenderoth, Lucia}, title = {Krisen und Auswege : Ringvorlesung im Wintersemester 2022/2023 an der TH Aschaffenburg}, editor = {Hofmann, Georg Rainer and Alm, Wolfgang}, publisher = {IMI Verlag, TH Aschaffenburg}, address = {Aschaffenburg}, organization = {TH Aschaffenburg}, isbn = {978-3-9823413-6-1}, pages = {44}, year = {2023}, abstract = {Krisen gab es schon immer. Aktuell hat sich jedoch ein ganzes Spektrum an Krisen entfaltet - es gibt politische und milit{\"a}rische Krisen, es brechen Energiem{\"a}rke und Lieferketten weg, wir sehen ganze Branchen gef{\"a}hrdet, auch die Gesundheit macht uns Sorgen, vom Klimawandel ganz zu schweigen. In den Veranstaltungen der Ringvorlesung „Krisen und Auswege", die im Wintersemester 2022/2023 stattfand, wurden Ph{\"a}nomene, Konzepte und L{\"o}sungen aus vielf{\"a}ltiger Perspektive erschlossen und damit die Komplexit{\"a}t des Gegenstands aufgezeigt. Herausforderungen f{\"u}r Unternehmen und Privatpersonen wurden identifiziert sowie der Einfluss auf technologische und organisatorische Entwicklungswege dargelegt. In dieser Publikation wurden die einzelnen Vortr{\"a}ge der Ringvorlesung von den Autorinnen zusammengefasst.}, subject = {Krise}, language = {de} } @book{AlmHofmannReuteretal.2023, author = {Alm, Wolfgang and Hofmann, Georg Rainer and Reuter, Carsten and Ruppert, Erich and Schumacher, Meike and Leimeister, Katja and Schmitt, Joachim and Wenderoth, Lucia}, title = {15 Jahre Wissenstransfer am Information Management Institut (IMI)}, organization = {TH Aschaffenburg}, isbn = {978-3-9823413-8-5}, pages = {78}, year = {2023}, abstract = {Im Sommer des Jahres 2022 hatte der Bayerische Landtag das neue Hochschulinnovationsgesetz (BayHIG) verabschiedet. Darin ist erstmals der Wissenstransfer als die dritte, neue S{\"a}ule der Hochschulaufgaben enthalten. Tats{\"a}chlich hat sich das IMI bereits seit 15 Jahren dem Wissenstransfer Hochschule - Wirtschaft verschrieben und zahlreiche Projekte mit unterschiedlichem Fokus erfolgreich durchgef{\"u}hrt. In der vorliegenden Publikation werden die bearbeiteten Themen im Wissenstransfer, die zahlreichen verschiedenen Veranstaltungsformate sowie die Drittmittelprojekte beleuchtet.}, subject = {Informationsmanagement}, language = {de} } @book{Hofmann2023, author = {Hofmann, Georg Rainer}, title = {Vertrauen als ein Verh{\"a}ltnis zwischen Menschen und Maschinen}, editor = {Alm, Wolfgang and Hofmann, Georg Rainer}, publisher = {IMI Verlag, TH Aschaffenburg}, address = {Aschaffenburg}, isbn = {978-3-9823413-7-8}, pages = {40}, year = {2023}, abstract = {Der technische Fortschritt von IT-Systemen, wie zum Beispiel der sogenannten „K{\"u}nstlichen Intelligenz" (KI) oder den „Common Data Spaces" (CDSs), bringt die Frage nach der Akzeptanz dieser Systeme mit sich. Sowohl die aktive ({\"o}konomische) Akzeptanz in Form des Erwerbs und der Nutzung, als auch die passive (soziale) Akzeptanz in Form der Duldung der aktiven Nutzung durch Dritte, sind f{\"u}r den Erfolg von IT-Systemen ausschlaggebend. Eine geringe Akzeptanz der Systeme und ein mangelndes Vertrauen in dieselben wird in einen Zusammenhang gebracht: Man fragt nach der Gestaltung „zuverl{\"a}ssiger und vertrauensw{\"u}rdiger Systeme", da diese besonders akzeptiert werden. In diesem Beitrag werden „Vertrauen" und dessen Zusammenhang mit „Zuverl{\"a}ssigkeit" und „Verstehen" im Kontext von IT-Systemen er{\"o}rtert.}, subject = {K{\"u}nstliche Intelligenz}, language = {de} } @article{LutzHelmTschirpkeetal.2023, author = {Lutz, Christian and Helm, Jonas and Tschirpke, Katrin and Esen, Cemal and Hellmann, Ralf}, title = {Drilling Sequence Optimization Using Evolutionary Algorithms to Reduce Heat Accumulation for Femtosecond Laser Drilling with Multi-Spot Beam Profiles}, series = {MDPI Materials}, volume = {2023}, journal = {MDPI Materials}, number = {16/5775}, doi = {10.3390/ma16175775}, pages = {1 -- 12}, year = {2023}, abstract = {We report on laser drilling borehole arrays using ultrashort pulsed lasers with a particular focus on reducing the inadvertent heat accumulation across the workpiece by optimizing the drilling sequence. For the optimization, evolutionary algorithms are used and their results are verified by thermal simulation using Comsol and experimentally evaluated using a thermal imaging camera. To enhance process efficiency in terms of boreholes drilled per second, multi-spot approaches are employed using a spatial light modulator. However, as higher temperatures occur across the workpiece when using simultaneous multi-spot drilling as compared to a single-spot process, a subtle spatial distribution and sequence of the multi-spot approach has to be selected in order to limit the resulting local heat input over the processing time. Different optimization approaches based on evolutionary algorithms aid to select those drilling sequences which allow for the combination of a high efficiency of multi-spot profiles, a low-generated process temperature and a high-component quality. In particular, using a 4 x 4 laser spot array allows for the drilling of 40,000 boreholes in less than 76 s (526 boreholes/s) with a reduced temperature increase by about 35\%, as compared to a single spot process when employing an optimized drilling sequence.}, subject = {Laserbohren}, language = {en} } @article{LutzSchwarzMarxetal.2023, author = {Lutz, Christian and Schwarz, Simon and Marx, Jan and Esen, Cemal and Hellmann, Ralf}, title = {Multi-Bessel Beams Generated by an Axicon and a Spatial Light Modulator for Drilling Applications}, series = {MDPI Photonics}, volume = {2023}, journal = {MDPI Photonics}, number = {10/413}, doi = {10.3390/photonics10040413}, pages = {1 -- 9}, year = {2023}, abstract = {We report on an optical setup to generate multi-Bessel beam profiles combining a refractive axicon and a spatial light modulator. Based on their particular beam profile, Bessel beams offer advantageous properties for micro drilling processes and internal volume processing, especially for transparent materials. In addition, the laser power of industrial, ultrashort pulsed lasers has increased significantly over the last few years, offering the possibility for highly efficient processes using multi-spot profiles. Our optical concept combines the dynamic possibilities of beam splitting using a spatial light modulator with the benefits of Bessel beams, which facilitates multi-Bessel beam processing. Beside the simulation and experimental evaluation of the generated multi-Bessel beams, we exemplify the applicability of the developed module for the perforation of thin metal foils by micro drilling.}, subject = {Bessel-B{\"u}ndel}, language = {en} } @article{SommerEsenHellmann2023, author = {Sommer, David and Esen, Cemal and Hellmann, Ralf}, title = {Static and Dynamic Mechanical Behaviour of Hybrid-PBF-LB/M-Built and Hot Isostatic Pressed Lattice Structures}, series = {Mechanical Properties of Polymeric, Metallic, and Composite Materials}, volume = {16}, journal = {Mechanical Properties of Polymeric, Metallic, and Composite Materials}, number = {9}, doi = {https://doi.org/10.3390/ma16093556}, pages = {1 -- 14}, year = {2023}, abstract = {We report on a comprehensive study of the mechanical properties of maraging steel body-centred cubic lattice structures fabricated by a hybrid additive manufacturing technology that combines laser powder bed fusion with in situ high-speed milling. As the mechanical properties of additive manufactured components are inferior to, e.g., cast components, surface modifications can improve the mechanical behaviour. Different hybrid additive manufacturing technologies have been designed using additive and subtractive processes, improving process quality. Following this, mechanical testing is performed with respect to static tensile properties and dynamic stress, hardness, and porosity, comparing specimens manufactured by laser powder bed fusion only to those manufactured by the hybrid approach. In addition, the influence of different heat-treatment techniques on the mechanical behaviour of the lattice structures is investigated, namely solution and aging treatment as well as hot isostatic pressing. Thus, the influence of the superior surface quality due to the hybrid approach is evaluated, leading to, e.g., an offset of about 14-16\% for the static testing of HIP lattice structures. Furthermore, the dynamic load behaviour can be improved with a finished surface, heading to a shift of the different zones of fatigue behaviour in the testing of hybrid-built specimens.}, subject = {Isostatisches Heißpressen}, language = {de} } @inproceedings{MarxEsenLutzetal.2023, author = {Marx, Jan and Esen, Cemal and Lutz, Christian and Hellmann, Ralf and Ostendorf, Andreas}, title = {Holographic tuning of physical axicons}, volume = {2023}, number = {154}, publisher = {LiM 2023 Proceedings}, pages = {1 -- 9}, year = {2023}, abstract = {Axicon generated Bessel beams are a popular tool for high aspect ratio precision laser drilling. Spot diameter and working distance are given by the geometric parameters of the axicon and the wavelength used. Thus, it is difficult to manipulate the beam shape of a Bessel beam for a given setup. Spatial light modulators (SLMs) overcome limitations in flexibility. However, due to the limited phase shift of SLMs, only Bessel beams with flat cone angles and large focal length can be generated. In this contribution, an approach for generating Bessel beams with a shorter, but tunable focal length is presented. A physical axicon was combined with an SLM. A holographic image of a negative axicon is put on the SLM to generate a ring beam, which is focused by a subsequent physical axicon to get a small focal diameter. Thus, different sized high aspect ratio micro holes can be drilled without using any moving components.}, subject = {Bessel-B{\"u}ndel}, language = {en} } @article{FlachsZhukovZechetal.2024, author = {Flachs, Dennis and Zhukov, Sergey and Zech, Isabella and Schreck, Timo and Belle, Stefan and von Seggern, Heiinz and Kupnik, Mario and Altmann, Alexander Anton and Thielemann, Christiane}, title = {Enzymatic Self-Degradable PLA-Based Electrets}, series = {Journal of Polymers and the Environment}, volume = {2024}, journal = {Journal of Polymers and the Environment}, number = {1}, doi = {Journal of https://doi.org/10.1007/s10924-024-03240-6}, pages = {1 -- 11}, year = {2024}, abstract = {In recent years, the demand for sustainable and degradable materials and electronic devices has increased significantly. Among a range of biodegradable polymers, poly(lactic acid) (PLA) is a good alternative to conventional petrol-based polymers because of its attractive mechanical properties and its easy processability. Recently, PLA has also been described as a promising dielectric material with piezoelectric and electret properties. We expect that PLA—after further optimization— will play an important role as a material for environmentally friendly sensors in the future, where first applications such as air filters and pressure sensors have already been proposed. However, degradation under normal ambient conditions is very slow, and an accelerated and controllable degradation process is highly desirable for any type of PLA-based sensors. Enzymatic hydrolysis with embedded enzymes has been proposed as an approach to accelerate and control degradation. In this work, we investigate the properties of PLA in terms of dielectric and mechanical properties with a focus on its ability to store charges after the enzyme proteinase K (Trit. album) has been incorporated. Results reveal that proteinase K has a positive effect on the charge stability of solvent-cast PLA electrets after complete evaporation of the solvent. Furthermore, we observed a concentration-dependent acceleration of mass loss in a Tris-HCl buffer. A fast degradation within only one day occurred at a concentration of 6 wt\% proteinase K.}, subject = {Biologisch abbaubarer Kunststoff}, language = {en} } @inproceedings{SauerGorksSpielmannetal.2023, author = {Sauer, Timm and Gorks, Manuel and Spielmann, Luca and Hepp, Nils and Zindler, Klaus and Jumar, Ulrich}, title = {AI-based control approaches for lateral vehicle guidance of industrial trucks}, series = {IFAC WC 2023 - The 22nd World Congress of the International Federation of Automatic Control 2023, Yokohama, Japan, 09.07.2023 - 14.07.2023}, booktitle = {IFAC WC 2023 - The 22nd World Congress of the International Federation of Automatic Control 2023, Yokohama, Japan, 09.07.2023 - 14.07.2023}, doi = {https://doi.org/10.1016/j.ifacol.2023.10.1501.}, year = {2023}, abstract = {Two different control concepts for the automatic track guidance of forklifts are proposed. Both approaches are based on Reinforcement Learning (RL), a method of Artificial Intelligence (AI), and are able to take into account time-variant parameters, such as the vehicle velocity, and to reduce the influence of the path curvature, the most important disturbance variable of lateral vehicle control. In the first approach, both, the path curvature and the vehicle velocity signal, are provided to the controller in addition to the state variables of the controlled system. By varying the corresponding parameters in the training process, both signals can be considered and the control parameters can be optimized accordingly. In the second approach, several controllers (multi-model concept) considering the path curvature are used and the varying vehicle velocity is taken into account using a gain-scheduling concept. Considering time-variant vehicle parameters and the influence of the disturbance variable during operation, a stable track guidance is guaranteed within the whole speed range of the industrial trucks.}, subject = {Flurf{\"o}rderer}, language = {en} } @article{BalleisWagner1998, author = {Balleis, Kristina and Wagner, Stefan}, title = {Haftung f{\"u}r Wildsch{\"a}den in gemeinschaftlichen Jagdbezirken}, series = {Zeitschrift f{\"u}r Jagdwissenschaft}, volume = {44}, journal = {Zeitschrift f{\"u}r Jagdwissenschaft}, number = {Juni}, pages = {85 -- 93}, year = {1998}, subject = {Jagdrecht}, language = {de} } @article{Balleis2000, author = {Balleis, Kristina}, title = {Keine Heilbarkeit eines Mangels unzureichender interkommunaler Abstimmung im erg{\"a}nzenden Verfahren nach \S215 a BauGB, Urteilsbesprechung}, series = {Verwaltungsrecht f{\"u}r die Anwaltspraxis}, volume = {2000}, journal = {Verwaltungsrecht f{\"u}r die Anwaltspraxis}, number = {6}, pages = {192 -- 192}, year = {2000}, subject = {Deutschland, Baugesetzbuch}, language = {de} } @article{Balleis2000, author = {Balleis, Kristina}, title = {Rechtswidrigkeit einer Vorkaufssatzung zur Sicherung st{\"a}dtebaulicher Entwicklung, Urteilsbesprechung}, series = {Verwaltungsrecht f{\"u}r die Anwaltspraxis}, volume = {2000}, journal = {Verwaltungsrecht f{\"u}r die Anwaltspraxis}, number = {5}, pages = {155 -- 155}, year = {2000}, subject = {Stadtentwicklung}, language = {de} } @article{Balleis1997, author = {Balleis, Kristina}, title = {Zul{\"a}ssigkeit und Notwendigkeit einer landesgesetzlichen Verbandsklage im Wasserrecht}, series = {Recht der Natur / Schnellbrief}, volume = {1997}, journal = {Recht der Natur / Schnellbrief}, number = {47}, pages = {18 -- 19}, year = {1997}, subject = {Verbandsklage}, language = {de} } @book{BalleisSchramlWagner1997, author = {Balleis, Kristina and Schraml, Ulrich and Wagner, Stefan}, title = {Jagdrecht und Verbandsklage : aktuelle Fragen des Jagdrechts und der Mitwirkungs- und Klagerechte von Naturschutzverb{\"a}nden im Wasserrecht}, publisher = {RIWA-Verlag}, address = {Augsburg}, isbn = {3-932374-01-0}, pages = {117}, year = {1997}, subject = {Verbandsklage}, language = {de} } @book{BalleisBielingHufnagletal.1995, author = {Balleis, Kristina and Bieling, Alfons and Hufnagl, Natalie and Kleinschmit von Lengefeld, Andreas and Riehtm{\"u}ller, Anne and R{\"o}hrscheid, Stefan and Suda, Michael and Timinger, Michael and Wagner, Stefan and Wiegmann, Stefanie}, title = {Rechtliche und fachliche Aspekte des Erhalts sch{\"u}tzenswerter W{\"a}lder}, publisher = {Fachverband Forst}, address = {Augsburg}, pages = {34}, year = {1995}, subject = {Forstschutz}, language = {de} } @book{WoerlenMetzlerMuellerKokemooretal.2022, author = {W{\"o}rlen, Rainer and Metzler-M{\"u}ller, Karin and Kokemoor, Axel and Balleis, Kristina}, title = {Schuldrecht BT}, publisher = {Vahlen}, address = {M{\"u}nchen}, isbn = {978-3-8006-6546-4}, pages = {298}, year = {2022}, subject = {Deutschland}, language = {de} } @book{WoerlenMetzlerMuellerBalleisetal.2023, author = {W{\"o}rlen, Rainer and Metzler-M{\"u}ller, Karin and Balleis, Kristina and Kokemoor, Axel}, title = {BGB AT}, publisher = {Vahlen}, address = {M{\"u}nchen}, isbn = {978-3-8006-6833-5}, pages = {259}, year = {2023}, subject = {Deutschland}, language = {de} } @book{WoerlenMetzlerMuellerBalleisetal.2023, author = {W{\"o}rlen, Rainer and Metzler-M{\"u}ller, Karin and Balleis, Kristina and Kokemoor, Axel}, title = {Schuldrecht AT}, publisher = {Vahlen}, address = {M{\"u}nchen}, isbn = {978-3-8006-7242-4}, pages = {260}, year = {2023}, subject = {Deutschland}, language = {de} } @inproceedings{RoetzelFehrenbacher2024, author = {R{\"o}tzel, Peter and Fehrenbacher, Dennis}, title = {Information Overload in Decision Support Systems}, series = {International Symposium on Accounting Information Systems}, volume = {2024}, booktitle = {International Symposium on Accounting Information Systems}, address = {Paphos}, year = {2024}, subject = {Entscheidungsunterst{\"u}tzungssystem}, language = {en} } @article{GvozdovskyyBratovaKazantsevaetal.2023, author = {Gvozdovskyy, Igor and Bratova, Daria and Kazantseva, Z. and Malyuta, S. and Lytvyn, Petro and Schwarz, Simon and Hellmann, Ralf}, title = {Light-controllable hybrid aligning layer based on LIPSS on sapphire surface and PVCN-F film}, series = {Journal of Molecular Liquids}, volume = {387}, journal = {Journal of Molecular Liquids}, number = {keine}, doi = {10.1016/j.molliq.2023.122623}, pages = {122623 -- 122623}, year = {2023}, abstract = {The creation of aligning layers for the uniform orientation of liquid crystals is significant for both research and the application of liquid crystals. For all applications, the creation of aligning layers possessing controllable characteristics such as azimuthal and polar anchoring energies, easy-axis of director alignment and pretilt angle, in the same way as it is achieved by using photoaligning layers processed by light, is very important. Here, aligning properties of hybrid aligning layers created on the basis of sapphire surfaces additionally coated by photoaligning layer of PVCN-F are studied. These hybrid layers possess the properties of the nano-structured sapphire layer and the photosensitive PVCN-F layer, and complement each other. The irradiation time dependence of the azimuthal anchoring energy of the hybrid layers is studied. By using certain experimental conditions during irradiation of hybrid layers, e.g., polarization of light and irradiation time, a minimum value of the azimuthal anchoring energy, close to zero, was obtained. Atomic force microscope studies of the irradiated hybrid layers were also carried out. It was found that the behavior of the contact angle of nematic droplets placed on treated sapphire surfaces are in good agreement with properties of hybrid aligning layers and parameters of structuring surface obtained from AFM images.}, subject = {Fl{\"u}ssigkristall}, language = {de} } @book{Borgeest2023, author = {Borgeest, Kai}, title = {内燃机测量技术和试验台架}, publisher = {China Machine Press}, isbn = {978-7-111-71807-9}, year = {2023}, subject = {Verbrennungsmotor}, language = {mul} } @article{HaefnerBischoffHelmetal.2023, author = {H{\"a}fner, Tom and Bischoff, Kay and Helm, Jonas and Kunz, Tim and Rung, Stefan and Esen, Cemal and Hellmann, Ralf}, title = {KEINE FREISCHALTUNG - Urheberrecht 0 bei Dokument mit Volltext Picosecond laser microvia drilling of ABF material using MHz burst mode}, series = {Materials Research Express}, volume = {10}, journal = {Materials Research Express}, number = {9}, pages = {096301 -- 096311}, year = {2023}, abstract = {We report on a comprehensive study of laser percussion microvia drilling of Ajinomoto build-up film (ABF) material using an ultrashort pulsed laser in MHz burst mode. After laser processing, microvia drilling quality is being evaluated by the fabricated diameter and taper using laser scanning microscopy and metallography. The influences of the incubation effect, heat accumulation and shielding effects as a result of pulse to pulse interactions are being discussed on the ablation threshold, penetration depth and laser microvia drilling quality. We find that an increasing heat accumulation in MHz burst mode processing is responsible for the void formation and delamination of the insulating ABF layer. Therefore, the parameter clearance is introduced to evaluate these effects on the microvia sidewalls. For a comparable clearance, applying 2 intra-burst pulses achieves an average reduced taper of down to 19.5\% compared to single pulse mode. At the same time, a reduced laser drilling time of 16.7\% per microvia highlights the enormous potential of the MHz burst mode for laser drilling of ABF material in printed circuit board fabrication.}, subject = {Ultrakurzzeitlaser}, language = {en} } @article{ZettlEsenHellmann2023, author = {Zettl, Julian and Esen, Cemal and Hellmann, Ralf}, title = {Fundamental Considerations and Analysis of the Energy Distribution in Laser Turning with Ultrashort Laser Pulses}, series = {mdpi Micromachines}, volume = {14}, journal = {mdpi Micromachines}, number = {10}, doi = {10.3390/mi14101838}, pages = {1 -- 15}, year = {2023}, abstract = {This article discusses the process of the laser turning of rotational symmetric, cylindrical components using ultrashort laser pulses with respect to the geometrical conditions and the resulting energy distribution during the laser turning process. As a result, process predictions and potential process optimizations are feasible. Particular attention is drawn to the laser spot formation on the cylindrical surface of the work piece in conjunction with the positioning of the laser beam relative to the rotation axis of the specimen. Based on fundamental calculations and experimental results, an optimum processing strategy is discussed, whereat the use of a trepanning optic in the laser turning process and the forming of a particular surface structure is additionally being issued.}, subject = {Ultrakurzzeitlaser}, language = {en} } @inproceedings{BischoffMueckeEsenetal.2023, author = {Bischoff, Kay and M{\"u}cke, Dominik and Esen, Cemal and Hellmann, Ralf}, title = {UV-Femtosecond-Laser Structuring of Silicon Carbide}, series = {International Congress on Applications of Lasers \& Electro-Optics (ICALEO) 2023}, booktitle = {International Congress on Applications of Lasers \& Electro-Optics (ICALEO) 2023}, year = {2023}, abstract = {We report on ultraviolet ultrashort pulsed laser processing of silicon carbide. Laser ablated cavities are evaluated with respect to their ablation rates, surface roughness and overall quality by varying the laser pulse fluence. Using this type of laser, high edge quality and surface roughness down to 107 nm can be achieved with an ablation efficiency of up to 0.228 mm 3 W -1 min -1. Functional surfaces are produced by generating laser induced periodic surface structures. The comparison with infrared wavelength underlines the advantages of the ultraviolet wavelength for laser micro machining this material. Significant differences with respect to the measured ablation depths and roughness as well as generated micro-and nanostructures appear. While infrared ablation is dominated by a chipping mechanism above a critical fluence of 9.93 Jcm -2 , higher ablation rates are observed with strong quality losses at the same time. In comparison to the infrared emission wavelength, in general , a significantly higher processing quality is achieved with the ultraviolet emission wavelength. In addition, the influence of spot size and repetition rate in UV processing is investigated. By increasing these parameters, a process acceleration without quality losses is enabled. The generation of a sophisticated microstructure exemplifies the advantages of processing silicon carbide with the UV laser reported here.}, subject = {Femtosekundenlaser}, language = {en} } @inproceedings{BischoffEsenHellmann2023, author = {Bischoff, Kay and Esen, Cemal and Hellmann, Ralf}, title = {Acceleration of Femtosecond Reductive Laser Sintering of Copper(II) Oxide for Conductive Copper Patterns on Cyclic Olefin Copolymers}, series = {International Congress on Applications of Lasers \& Electro-Optics (ICALEO) 2023}, booktitle = {International Congress on Applications of Lasers \& Electro-Optics (ICALEO) 2023}, year = {2023}, abstract = {We report on the acceleration of femtosecond reductive laser sintering of copper (II) oxide on the surface of transparent cyclic olefin copolymers (COC) by varying the focus size to generate metallic copper (Cu) layers. By using different focusing conditions, different process speeds are achieved, and the structural accuracies are controlled. The formation of Cu lines is observed for different focus sizes at various scan speeds, which is attributed to laser exposure duration and chemical reaction time. The formed lines are categorized and measured by optical microscopy and provide the basis for two-dimensional Cu surfaces. By hatching, high quality conductive films are produced with an increased focus diameter of up to 400 µm at a scan speed of 400 mm/s and a hatch distance of 250 µm resulting in a multiple increased process speed by a factor of thirteen compared to previous research. Using 4-tip measurement , a low sheet resistance of 0.165 Ω/sq was validated on these Cu films, which have an atomic Cu content of 89.5\%.}, subject = {Femtosekundenlaser}, language = {en} } @article{DobrovolskijStark2024, author = {Dobrovolskij, Dascha and Stark, Hans-Georg}, title = {Synthetic demand data generation for individual electricity consumers: Inpainting}, series = {Energy and AI}, volume = {15}, journal = {Energy and AI}, number = {Januar 2024}, pages = {100312 -- 100320}, year = {2024}, abstract = {In this contribution we deal with the problem of producing "reasonable" data, when considering recorded energy consumption data, which are at certain sections incomplete and/or erroneous. This task is important, when energy providers employ prediction models for expected energy consumption, which are based on past recorded consumption data, which then of course should be reliable and valid. In a related contribution Yilmaz (2022), GAN-based methods for producing such "artificial data" have been investigated. In this contribution, we describe an alternative and complementary method based on signal inpainting, which has been successfully applied to audio processing Lieb and Stark (2018). After giving a short overview of the theory of proximity-based convex optimization, we describe and adapt an iterative inpainting scheme to our problem. The usefulness of this approach is demonstrated by analyzing real-world-data provided by a German energy supplier.}, subject = {Energieverbrauch}, language = {en} } @article{LiebKnopp2021, author = {Lieb, Florian and Knopp, Tobias}, title = {A wavelet-based sparse row-action method for image reconstruction in magnetic particle imaging}, series = {Medical Physics}, volume = {48}, journal = {Medical Physics}, number = {7}, pages = {3893 -- 3903}, year = {2021}, abstract = {Purpose Magnetic particle imaging (MPI) is a preclinical imaging technique capable of visualizing the spatio-temporal distribution of magnetic nanoparticles. The image reconstruction of this fast and dynamic process relies on efficiently solving an ill-posed inverse problem. Current approaches to reconstruct the tracer concentration from its measurements are either adapted to image characteristics of MPI but suffer from higher computational complexity and slower convergence or are fast but lack in the image quality of the reconstructed images. Methods In this work we propose a novel MPI reconstruction method to combine the advantages of both approaches into a single algorithm. The underlying sparsity prior is based on an undecimated wavelet transform and is integrated into a fast row-action framework to solve the corresponding MPI minimization problem. Results Its performance is numerically evaluated against a classical FISTA (Fast Iterative Shrinkage-Thresholding Algorithm) approach on simulated and real MPI data. The experimental results show that the proposed method increases image quality with significantly reduced computation times. Conclusions In comparison to state-of-the-art MPI reconstruction methods, our approach shows better reconstruction results and at the same time accelerates the convergence rate of the underlying row-action algorithm.}, subject = {Wavelet}, language = {en} } @article{BischoffEsenHellmann2023, author = {Bischoff, Kay and Esen, Cemal and Hellmann, Ralf}, title = {Preparation of Dispersed Copper(II) Oxide Nanosuspensions as Precursor for Femtosecond Reductive Laser Sintering by High-Energy Ball Milling}, series = {Nanomaterials}, volume = {13}, journal = {Nanomaterials}, number = {19}, doi = {https://doi.org/10.3390/nano13192693}, pages = {2693 -- 2693}, year = {2023}, abstract = {This contribution demonstrates and discusses the preparation of finely dispersed copper(II) oxide nanosuspensions as precursors for reductive laser sintering (RLS). Since the presence of agglomerates interferes with the various RLS sub-processes, fine dispersion is required, and oversized particles must be identified by a measurement methodology. Aside from the established method of scanning electron microscopy for imaging individual dried particles, this work applies the holistic and statistically more significant laser diffraction in combination with dynamic image analysis in wet dispersion. In addition to direct ultrasonic homogenization, high-energy ball milling is introduced for RLS, to produce stable nanosuspensions with a high fine fraction, and, above all, the absence of oversize particles. Whereas ultrasonic dispersion stagnates at particle sizes between 500 nm and 20 μm, even after 8 h, milled suspension contains a high proportion of finest particles with diameters below 100 nm, no agglomerates larger than 1 μm and a trimodal particle size distribution with the median at 50 nm already, after 100 min of milling. The precursor layers produced by doctor blade coating are examined for their quality by laser scanning microscopy. The surface roughness of such a dry film can be reduced from 1.26 μm to 88 nm by milling. Finally, the novel precursor is used for femtosecond RLS, to produce homogeneous, high-quality copper layers with a sheet resistance of 0.28 Ω/sq and a copper mass concentration of 94.2\%.}, subject = {Laserstrahlsintern}, language = {en} } @article{BischoffKeferWienkeetal.2023, author = {Bischoff, Kay and Kefer, Stefan and Wienke, Alexander and Overmeyer, Ludger and Kaierle, Stefan and Esen, Cemal and Hellmann, Ralf}, title = {Integration of Bragg gratings in aerosol-jetted polymer optical waveguides for strain monitoring capabilities}, series = {Optics Letters}, volume = {48}, journal = {Optics Letters}, number = {7}, doi = {https://doi.org/10.1364/OL.481801}, pages = {1778 -- 1781}, year = {2023}, abstract = {We demonstrate and discuss the integration of Bragg gratings in aerosol-jetted polymer optical waveguides, produced in the optical assembly and connection technology for component-integrated bus systems (OPTAVER) process. By using a femtosecond laser and adaptive beam shaping, an elliptical focal voxel generates different types of single pulse modification by nonlinear absorption in the waveguide material, which are arranged periodically to form Bragg gratings. Integration of a single grating structure or, alternatively, an array of Bragg grating structures in the multimode waveguide yields a pronounced reflection signal with typical multimodal properties, i.e., a number of reflection peaks with non-Gaussian shapes. However, the main wavelength of reflection, located around 1555 nm, is evaluable by means of an appropriate smoothing algorithm. When loaded by mechanical bending, a pronounced Bragg wavelength shift of this reflected peak up to 160 pm is detected. This demonstrates that the additively manufactured waveguides can be used not only for signal transmission but also as a sensor.}, subject = {Bragg-Reflektor}, language = {de} } @inproceedings{FranzMueckeKunzetal.2023, author = {Franz, Daniel and M{\"u}cke, Dominik and Kunz, Tim and Rung, Stefan and Esen, Cemal and Hellmann, Ralf}, title = {UV picosecond laser drilling of ABF film material for printed circuit boards using laser burst mode and beam shaping}, series = {International Congress on Applications of Lasers \& Electro-Optics (ICALEO) 2023}, booktitle = {International Congress on Applications of Lasers \& Electro-Optics (ICALEO) 2023}, year = {2023}, abstract = {We report on an experimental study of laser microvia percussion drilling of Ajinomoto build-up film (ABF) material using an ultrashort pulsed laser in the ultraviolet region. In order to optimize the drilling quality in terms of the fabricated taper and microvia diameter, the MHz burst mode is used in combination with both a Gaussian and a top-hat laser intensity distribution. To evaluate the influence of the top-hat beam shape on defocusing, microvias were drilled at different z-positions in the range of 200 μm evenly distributed around the focal plane. The drilling quality was evaluated by laser scanning microscopy and metallography. When using a top-hat beam shape, a reduced taper of down to 26.8 \% on average is achieved compared to a Gaussian beam. For the application of 3 intra-burst pulses, we find an improvement of the taper by 11.6\% compared to the single pulse mode due to the increasing heat accumulation. Using a top-hat beam shape in combination with the MHz burst mode, an 18.2 \% reduction in laser drilling time for a microvia with a similar taper is remarkable, demonstrating the high potential for scaling throughput in electronics manufacturing.}, subject = {Pikosekundenbereich}, language = {en} } @article{BischoffMueckeRothetal.2022, author = {Bischoff, Kay and M{\"u}cke, Dominik and Roth, Gian-Luca and Esen, Cemal and Hellmann, Ralf}, title = {UV-Femtosecond-Laser Structuring of Cyclic Olefin Copolymer}, series = {Polymers}, volume = {14}, journal = {Polymers}, number = {14}, doi = {https://doi.org/10.3390/polym14142962}, pages = {2962 -- 2962}, year = {2022}, abstract = {We report on the laser ablation of cyclic olefin copolymer using an amplified ultrashort pulsed laser in the ultraviolet spectral range. In addition to a high ablation depth per laser-structured layer up to 74 μm at a fluence of 22 J cm-2, an excellent mean roughness 𝑅𝑎 of laser-patterned surfaces down to 0.5 μm is demonstrated. Furthermore, with increasing fluence, increasing ablation efficiencies up to 2.5 mm3 W-1 min-1 are determined. Regarding the quality of the ablation, we observed steep ablation flanks and low debris formation, though for fluences above 10.5 J cm-2 the formation of troughs was observed, being attributed to multiple reflections on the ablation flanks. For comparison, laser ablation was performed under identical conditions with an infrared laser wavelength. The results highlight that UV ablation exhibits significant advantages in terms of ablation efficiency, surface roughness and quality. Moreover, our results show that a larger UV focus spot accelerates the ablation process with comparable quality, paving the way for high-power UV ultrashort pulsed lasers towards an efficient and qualitative tool for the laser machining of cyclic olefin copolymer. The production of complex microfluidics further underlines the suitability of this type of laser.}, subject = {Femtosekundenlaser}, language = {en} } @article{FranzYangMicheletal.2023, author = {Franz, Daniel and Yang, Yongting and Michel, Luis and Esen, Cemal and Hellmann, Ralf}, title = {Evaluation of an ultrashort pulsed laser robot system for flexible and large-area micromachining}, series = {Journal of Laser Applications}, volume = {35}, journal = {Journal of Laser Applications}, number = {4}, pages = {042057 -- 042065}, year = {2023}, abstract = {We report for the first time on the realization, characterization and application of an ultrashort pulsed laser robot system for flexible and large-area 2D and 3D laser micromachining with 6 articulated axes. To characterize the dynamic positioning of the laser beam during and after axes movement, CMOS image sensors were integrated into the beam path. A method introduced for the alignment of the optical axes allows a reduction of the deviations in laser beam positioning to less than 141.8 ± 92.9 μm within a 110° rotation range of axis 4. In addition, a high laser beam positioning repeatability of less than 102.2 μm is demonstrated over a total period of 14 h for a movement of axis 5 within a range of 0° to 90°. Initial laser cutting, laser structuring and laser marking applications on automotive dashboards and glass substrates are presented for flexible and large area 2D and 3D manufacturing. By applying a special laser cutting strategy for processing AF 32 eco thin glass, high cutting quality is achieved with a taper of up to 96.3\% without the generation of cracks, demonstrating the innovative potential of the high-precision laser robot system. Nonetheless, different identified inherent influences of each axis 1-5 during robot axis movement demand for an innovative beam stabilization concept to achieve high precision in laser beam positioning.}, subject = {Ultrakurzzeitlaser}, language = {en} } @inproceedings{DoehringStieglitzFriedrichetal.2023, author = {D{\"o}hring, Thorsten and Stieglitz, Veronika and Friedrich, Peter and Burwitz, Vadim and Jelinek, Martin and Hudec, Rene}, title = {Testing of lobster-eye type telescopes with X-rays and visible light}, series = {SPIE Proceedings}, volume = {2023}, booktitle = {SPIE Proceedings}, number = {12576}, publisher = {SPIE}, organization = {TH Aschaffenburg}, doi = {https://doi.org/10.1117/12.2665429}, pages = {1257606-1 -- 1257606-5}, year = {2023}, abstract = {Reflective coatings for astronomical X-ray optics were developed at the "Aschaffenburg Competence Center for Astronomical and Space Instrumentation" (ACCASI) since several years. As part of a Bavarian-Czech cooperation between the Technical University of Aschaffenburg and the Czech Technical University of Prague, now two mechanically identical telescopes were built. One telescope optic was equipped with conventional gold-coated mirrors, manufactured by the Czech project partners. The 34 X-ray mirrors of the second telescope use an innovative coating system made of chromium and iridium, which was applied at the Aschaffenburg coating laboratory. Both telescopes are designed according to the bionic principle of a reflecting lobster eye. The optics works with two consecutive reflections on mutually perpendicular mirror surfaces. This enables a large field of view with many square degrees in diameter, which, however, comes at the price of a reduced angular resolution. An extensive X-ray characterization of these telescopes was carried out at the PANTER test facility of MPE, which simulates parallel starlight incident on the telescopes. The telescopes have an angular resolution of about 4 arc minutes in X-rays and a focal length of about 2 meters. Furthermore, the used X-ray mirrors reflect and focus visible light as well and this functionality in the optical regime was checked in laboratory tests. Now another test campaign was done to examine the telescope resolution for real objects of the visible sky and the imaging properties for star constellations. Such functional tests by observing astronomical objects of the visible sky may simplify and accelerate the development of X-ray telescopes for satellite applications.}, subject = {R{\"o}ntgenteleskop}, language = {en} } @article{RaiynWeidl2024, author = {Raiyn, Jamal and Weidl, Galia}, title = {Predicting Autonomous Driving Behavior through Human Factor Considerations in Safety-Critical Events}, series = {Smart Cities}, volume = {7}, journal = {Smart Cities}, number = {1}, doi = {https://doi.org/10.3390/ smartcities7010018}, pages = {460 -- 474}, year = {2024}, abstract = {This paper investigates the ability of autonomous driving systems to predict outcomes by considering human factors like gender, age, and driving experience, particularly in the context of safety-critical events. The primary objective is to equip autonomous vehicles with the capacity to make plausible deductions, handle conflicting data, and adjust their responses in real-time during safety-critical situations. A foundational dataset, which encompasses various driving scenarios such as lane changes, merging, and navigating complex intersections, is employed to enable vehicles to exhibit appropriate behavior and make sound decisions in critical safety events. The deep learning model incorporates personalized cognitive agents for each driver, considering their distinct preferences, characteristics, and requirements. This personalized approach aims to enhance the safety and efficiency of autonomous driving, contributing to the ongoing development of intelligent transportation systems. The efforts made contribute to advancements in safety, efficiency, and overall performance within autonomous driving systems. To describe the causal relationship between external factors like weather conditions and human factors, and safety-critical driver behaviors, various data mining techniques can be applied. One commonly used method is regression analysis. Additionally, correlation analysis is employed to reveal relationships between different factors, helping to identify the strength and direction of their impact on safety-critical driver behavior. Keywords: car following; decision making; driving behavior; naturalistic driving studies; safety-critical events; cognitive vehicles 1. Introduction Despite the increasing prevalence of vehicle automation, the persistently high number of car crashes remains a concern. Safety-critical events in human-driven scenarios have become more intricate and partially uncontrollable due to unforeseen circumstances. Investigating human driving behavior is imperative to establish traffic baselines for mixed traffic, encompassing traditional, automated, and autonomous vehicles (AVs). Various factors, such as weather conditions affecting visibility in longitudinal car-following (CF) behavior [1,2], influence human driving behavior [3]. Car-following behavior, illustrating how a following vehicle responds to the lead vehicle in the same lane, is a crucial aspect. Existing car-following models often make assumptions about homogeneous drivers, neglecting significant heterogeneity in driving experience, gender, character, emotions, and sociological, psychological, and physiological traits. Failing to account for this heterogeneity hampers a comprehensive understanding of car-following behavior, limiting model accuracy and applicability. In the development of more realistic car-following models for mixed traffic, acknowledging the diversity among drivers is crucial. By including individual variations such as risk-taking tendencies, reaction times, decision-making processes, and driving styles, the modeling of real-world driving complexities can be improved. Simplifying drivers into a few categories overlooks the richness and variety of their characteristics, prompting the need for a more comprehensive approach to capture nuances within different driver profiles. To address these Smart Cities}, subject = {Autonomes Fahrzeug}, language = {en} } @inproceedings{KeferSchmaussHellmann2023, author = {Kefer, Stefan and Schmauss, Bernhard and Hellmann, Ralf}, title = {Sapphire-Based Planar Bragg Grating Devices}, series = {28th International Conference on Optical Fiber Sensors}, booktitle = {28th International Conference on Optical Fiber Sensors}, isbn = {978-1-957171-30-2}, doi = {10.1364/OFS.2023.W2.4}, year = {2023}, abstract = {This study reports on the long-term stability and the high-temperature capability of sapphire-based photonic crystal waveguides with integrated Bragg gratings. Furthermore, their Bragg grating reflectivity as well as their temperature sensitivity is quantified.}, subject = {Bragg-Reflektor}, language = {en} } @inproceedings{KeferPapeSchmaussetal.2023, author = {Kefer, Stefan and Pape, Natalie and Schmauss, Bernhard and Hellmann, Ralf}, title = {Fabrication of Lattice-Like Waveguides in Planar Cyclic Olefin Copolymers}, series = {28th International Conference on Optical Fiber Sensors}, booktitle = {28th International Conference on Optical Fiber Sensors}, isbn = {978-1-957171-30-2}, doi = {10.1364/OFS.2023.Th6.69}, year = {2023}, abstract = {This work demonstrates the femtosecond laser-based fabrication of lattice-like waveguides in planar cyclic olefin copolymers. An overview of the fabrication process is provided and waveguiding in the C-band is proven via optical near-field analysis.}, subject = {Wellenleiter}, language = {en} } @article{KeferLimbachPapeetal.2024, author = {Kefer, Stefan and Limbach, Tobias and Pape, Natalie and Klamt, Kathrin and Schmauss, Bernhard and Hellmann, Ralf}, title = {Birefringence in Injection-Molded Cyclic Olefin Copolymer Substrates and Its Impact on Integrated Photonic Structures}, series = {Polymers}, volume = {16}, journal = {Polymers}, number = {2}, doi = {10.3390/polym16020168}, pages = {168 -- 168}, year = {2024}, abstract = {This contribution quantifies the birefringence within injection-molded cyclic olefin copolymer plates and discusses its impact on the mechanical properties of the plates. It also focuses on the impact of birefringence on integrated waveguides and Bragg gratings and provides fabrication guidelines for such structures. The anisotropy in all three dimensions of the workpiece is examined by means of polarimetry and a prism coupler. It is found that the birefringence is inhomogenously distributed within the workpieces, whereas the maximum birefringence not only varies locally, but also depends on the observation direction. Overall, a maximum birefringence of 10 × 10-4 is found at the plate's surface near the injection gate. The anisotropy then reduces exponentially towards the center of the workpiece and saturates at 1.8 × 10-4, in a depth of 0.4 mm. Thus, the birefringence strongly affects near-surface photonic structures. It is found that, depending on their orientation and the local birefringence of the substrate, waveguides and Bragg gratings fabricated with comparable parameters behave completely differently in terms of polarization-dependent optical attenuation, cross-sectional intensity distribution and Bragg reflection signal. For example, the support of the TM mode can vary between total loss and an optical attenuation of 0.9 dB × cm-1. In consequence, this study underlines the importance of quantifying the birefringent state of an injection-molded cyclic olefin copolymer workpiece if it is supposed to serve as a substrate for integrated photonic structures. The study furthermore demonstrates that birefringence effects can be omitted by burying the photonic structures deeper into the volume of the thermoplastic.}, subject = {Bragg-Reflektor}, language = {en} } @inproceedings{NormannHaugValenciaetal.2023, author = {Normann, Marc and Haug, Jim and Valencia, Yeimy and Abke, J{\"o}rg and Hagel, Georg}, title = {Adaptive Learning Path Sequencing Based on Learning Styles within N-dimensional Spaces}, series = {ECSEE '23: Proceedings of the 5th European Conference on Software Engineering Education}, volume = {2023}, booktitle = {ECSEE '23: Proceedings of the 5th European Conference on Software Engineering Education}, editor = {Mottock, J{\"u}rgen and Hagel, Georg}, doi = {https://doi.org/10.1145/3593663.3593676}, pages = {56 -- 64}, year = {2023}, abstract = {Planning adaptive learning paths for students' progress throughout a course can be a challenging task, although it can be helpful for their learning progress. Within the HASKI-System, students should be able to get their own, personalized learning paths. In this paper, we present an approach towards the learning path sequencing problem. This idea is based on a novel proposal for arranging learning objects in a multi-dimensional space, bringing the relationship and similarities of these objects into a new relationship. We show, that we can use both, the Ant Colony Optimization Algorithm and the Genetic Algorithm with the idea of the Traveling-Salesman-Problem and get results, that are comparable with a proposed literature-based adaption mechanism. Nevertheless, the learning paths are all personalized based on the Felder \& Silverman Learning Style Model and the hyperspace model will allow us later on to include more dimensions for other influencing factors.}, subject = {Lernstil}, language = {en} } @article{TrentThielemannMonici2024, author = {Trent, Davis and Thielemann, Christiane and Monici, Monica}, title = {How are cell and tissue structure and function influenced by gravity and what are the gravity perception mechanisms?}, series = {npj Microgravity}, volume = {2014}, journal = {npj Microgravity}, number = {10 / 16}, doi = {10.1038/s41526-024-00357-9}, pages = {1 -- 7}, year = {2024}, abstract = {Progress in mechanobiology allowed us to better understand the important role of mechanical forces in the regulation of biological processes. Space research in the field of life sciences clearly showed that gravity plays a crucial role in biological processes. The space environment offers the unique opportunity to carry out experiments without gravity, helping us not only to understand the effects of gravitational alterations on biological systems but also the mechanisms underlying mechanoperception and cell/tissue response to mechanical and gravitational stresses. Despite the progress made so far, for future space exploration programs it is necessary to increase our knowledge on the mechanotransduction processes as well as on the molecular mechanisms underlying microgravity-induced cell and tissue alterations. This white paper reports the suggestions and recommendations of the SciSpacE Science Community for the elaboration of the section of the European Space Agency roadmap "Biology in Space and Analogue Environments" focusing on "How are cells and tissues influenced by gravity and what are the gravity perception mechanisms?" The knowledge gaps that prevent the Science Community from fully answering this question and the activities proposed to fill them are discussed.}, subject = {Zellkultur}, language = {en} } @inproceedings{VoigtMoeckel2022, author = {Voigt, Jorrit and Moeckel, Michael}, title = {Modelling dynamic 3D heat transfer in laser material processing based on physics informed neural networks}, doi = {10.1051/epjconf/202226602010}, year = {2022}, abstract = {Machine learning algorithms make predictions by fitting highly parameterized nonlinear functions to massive amounts of data. Yet those models are not necessarily consistent with physical laws and offer limited interpretability. Extending machine learning models by introducing scientific knowledge in the optimization problem is known as physics-based and data-driven modelling. A promising development are physics informed neural networks (PINN) which ensure consistency to both physical laws and measured data. The aim of this research is to model the time-dependent temperature profile in bulk materials following the passage of a moving laser focus by a PINN. The results from the PINN agree essentially with finite element simulations, proving the suitability of the approach. New perspectives for applications in laser material processing arise when PINNs are integrated in monitoring systems or used for model predictive control.}, subject = {Neuronales Netz}, language = {en} } @inproceedings{AkcatepeMoeckel2023, author = {Akcatepe, Osman and Moeckel, Michael}, title = {Hybrid Physics-Inspired Machine Learning Framework for Predictive Maintenance of Forklift Chains: Leveraging Sensor Data Characteristics}, doi = {10.1109/ICCMA59762.2023.10375057}, year = {2023}, abstract = {Bridging the gap between physics-based modeling and data-driven machine learning promises to reduce the amount of training data required and to improve explainability in predictive maintenance applications. For a small fleet of industrial forklift trucks, we develop a physically inspired framework for predicting remaining useful life (RUL) for selected components by integrating physically motivated feature extraction, degradation modelling and machine learning. The discussed approach is promising for situations of limited data availability or large data heterogeneity, which often occurs in fleets of customized vehicles optimized for particular tasks.}, subject = {Maschinelles Lernen}, language = {en} } @article{VoigtMoeckel2022, author = {Voigt, Jorrit and Moeckel, Michael}, title = {Benchmarking a multi-layer approach and neural network architectures for defect detection in PBF-LB/M}, series = {Materials Today Communications}, volume = {2022}, journal = {Materials Today Communications}, number = {33/104878}, doi = {https://doi.org/10.1016/j.mtcomm.2022.104878}, pages = {* -- *}, year = {2022}, abstract = {The substitution of expensive non-destructive material testing by data-based process monitoring is intensively explored in quality assurance for additive manufactured components. Machine learning show promising results for defect detection but require conceptual adaption to layer wise manufacturing and line scanning patterns in laser powder bed fusion. A multi-layer approach to co-register µ-computer tomography measurements with process monitoring data is developed and a workflow for automatic data set generation is implemented. The objective of this research is to benchmark the volumetric multi-layer approach and specifically selected deep learning methods for defect detection. The volumetric approach shows superior results compared to single slice monitoring. All investigated structured neural network topologies deliver similar performance.}, subject = {Neuronales Netz}, language = {en} }