@inbook{46809, author = {{Rossel, M. and Meschut, G.}}, booktitle = {{Lecture Notes in Mechanical Engineering}}, isbn = {{9783031413407}}, issn = {{2195-4356}}, publisher = {{Springer Nature Switzerland}}, title = {{{Modeling and Parameterization for a 3D Simulation of Clinching with an Extensible Die}}}, doi = {{10.1007/978-3-031-41341-4_9}}, year = {{2023}}, } @article{46818, abstract = {{AbstractObjectiveConcerns about short‐ and long‐term consequences of repetitive heading contributed to heading restrictions in youth football in some countries. This prospective longitudinal cohort study aims to describe heading exposure in children's and youth football over two seasons using standardized video analysis.MethodsAll matches and training sessions of a male Under‐11 (n = 29), Under‐15 (n = 28), Under‐19 (n = 38), and female Under‐17 (n = 39) team were videotaped during the seasons 2019–2020 and 2020–2021. Heading frequencies and characteristics were analyzed. Individual heading exposure is presented as average incidence rates (IR) per 1000 match/training hours.ResultsIn 275 matches and 673 training sessions, 22 921 headers were observed. Heading IR per player in matches was 1256 (Under‐11 m), 1608 (Under‐15 m), 1050 (Under‐17 f), and 1966 (Under‐19 m). In training sessions, IR per player was 739 (Under‐11 m), 2206 (Under‐15 m), 1661 (Under‐17 f), and 1419 (Under‐19 m). Five Under‐15 males headed the ball five to eight times per training on average. Most headers were performed without heading duels. Flight distance was predominantly 5–20 m (54%) in matches and <5 m (65%) in training. While head impact location most frequently was at frontal areas, one‐third of all headers in Under‐11 in matches hit temporal, parietal, and occipital parts of the head.ConclusionHeading incidence was low in the youngest age group, whereas (predominantly five) Under‐15 males showed very high heading exposures in training. In assessment and regulation of heading burden, training sessions and individual heading behavior should specifically be addressed. Recommendations for heading the ball in practice should account for individual and age‐related differences.}}, author = {{Reeschke, Rebecca and Haase, Franziska Katharina and Dautzenberg, Lena and Krutsch, Werner and Reinsberger, Claus}}, issn = {{0905-7188}}, journal = {{Scandinavian Journal of Medicine & Science in Sports}}, keywords = {{Physical Therapy, Sports Therapy and Rehabilitation, Orthopedics and Sports Medicine}}, number = {{9}}, pages = {{1821--1830}}, publisher = {{Wiley}}, title = {{{Training matters: Heading incidence and characteristics in children's and youth football (soccer) players}}}, doi = {{10.1111/sms.14408}}, volume = {{33}}, year = {{2023}}, } @inproceedings{46957, abstract = {{Modern companies often face various challenges in concept development of products or systems. Design engineers prepare initial concepts as 3D models. These are then simulated by computational engineers. If requirements are not met, this necessitates an iterative process that runs between the design and computation departments until a valid concept is created. Design methods such as topology optimization are often used here. The upcoming result is then attempted to be adapted to certain manufacturing processes. These iteration loops can sometimes take a very long time, since the model construction and structural optimization generate large computational efforts. The present work shows on an example a methodical approach, which represents a first proof of concept, to solving this problem, including a description of methods and techniques, as well as possible problems in a detailed analysis concerning training data for neural networks and their abstraction capabilities. It is evident that additional research work needs to be conducted for further utilization in order to address all arising questions.}}, author = {{Ott, Manuel and Meihöfener, Niclas and Mozgova, Iryna}}, booktitle = {{Proceedings of the 34rd Annual International Solid Freeform Fabrication Symposium 2023}}, editor = {{Ott, Manuel}}, location = {{Austin, Texas, United States}}, title = {{{Methodical Approach to Reducing Design Time by using Neural Networks in Early Stages of Concept Development}}}, year = {{2023}}, } @phdthesis{56937, abstract = {{Ein Trend in der Produktion sind individualisierte Produkte und damit eine höhere Variantenvielfalt, die idealerweise durch effiziente Produktionsprozesse hergestellt werden. Effizienz bedeutet in diesem Fall, dass die Produkte kostengünstig und bedarfsgerecht hergestellt werden. Der Trend geht hierbei auch in der Massenproduktion zu einer flexiblen Produktion, um das gebundene Kapital zu reduzieren und zeitnah auf Kundenwünsche reagieren zu können. Dies führt zu einem häufigeren Umrüsten der Werkzeuge in den Maschinen und somit zu einem immer häufigeren Einrichten der Prozesse.In dieser Arbeit wird eine Systematik für ein adaptives Einrichtassistenzsystem entwickelt, welches den Maschinenbediener beim Einrichten mithilfe eines definierten Vorgehens durch den Prozess leitet. Der Bediener wird dabei unterstützt die momentane Produktqualität zu bewerten und bekommt einen quantitativen Vorschlag zur Variation der Justagemöglichkeiten. So kann der Einrichtprozess zielgerichteter und fehlerfreier durchgeführt werden. Ermöglicht wird dies durch die Abbildung des notwendigen Expertenwissens in datengetriebenen Modellen. Mithilfe des so abgebildeten Expertenwissens werden optimierte Einstellungen berechnet und am Werkzeug eingestellt. Es ist nicht davon auszugehen, dass das virtualisierte Expertenwissen die Realität allumfassend abbilden und alle akuten Umwelteinflüsse messtechnisch ermittelt werden können. Etwaige Abweichungen der Produktqualität werden direkt in der entwickelten Optimierung und bei Bedarf mithilfe der vorgeschlagenen Kompensationsstrategie eliminiert.Die Systematik wird anhand eines Folgeverbundprozesses validiert. Nach der Analyse des Prozesses werden die wesentlichen Komponenten für das System entwickelt und mithilfe von Versuchen und Simulationen die Funktionsfähigkeit erfolgreich nachgewiesen.}}, author = {{Gräler, Manuel}}, publisher = {{Verlagsschriftenreihe des Heinz Nixdorf Instituts}}, title = {{{Entwicklung adaptiver Einrichtassistenzsysteme für Produktionsprozesse}}}, doi = {{10.17619/UNIPB/1-1894}}, volume = {{417}}, year = {{2023}}, } @inbook{57221, author = {{Babu, Sandeep and Jegarian, Majid and Fischer, Dirk and Mertsching, Bärbel}}, booktitle = {{Lecture Notes in Computer Science}}, isbn = {{9783031433597}}, issn = {{0302-9743}}, publisher = {{Springer Nature Switzerland}}, title = {{{Fast 3D Semantic Segmentation Using a Self Attention Network and Random Sampling}}}, doi = {{10.1007/978-3-031-43360-3_21}}, year = {{2023}}, } @article{59184, author = {{Jalowy, Jonas}}, issn = {{0246-0203}}, journal = {{Annales de l'Institut Henri Poincaré, Probabilités et Statistiques}}, number = {{4}}, publisher = {{Institute of Mathematical Statistics}}, title = {{{The Wasserstein distance to the circular law}}}, doi = {{10.1214/22-aihp1317}}, volume = {{59}}, year = {{2023}}, } @article{60095, abstract = {{AbstractEndurance training has been shown to be effective in treating adolescents with major depressive disorder (MDD). To integrate endurance training into the therapeutic setting and the adolescents' daily lives, the current performance status of the adolescents should be accurately assessed. This study aims to examine adolescents with MDD concerning exhaustion criteria during a cardiopulmonary exercise test (CPET), as well as to compare the values obtained thereon with sex- and age-related control values. The study included a retrospective examination of exhaustion criteria ((i) oxygen consumption (V̇O2) plateau, (ii) peak respiratory exchange ratio (RERpeak) > 1.0, (iii) peak heart rate (HRpeak) ≥ 95% of the age-predicted maximal HR, and (iv) peak blood lactate concentration (BLCpeak) > 8.0 mmol⋅L−1) during a graded CPET on a cycle ergometer in adolescents with MDD (n = 57). Subsequently, maximal V̇O2, peak minute ventilation, V̇O2 at the first ventilatory threshold, and peak work rate of participants who met at least two of four criteria were compared with published control values using an independent-sample t-test. Thirty-three percent of the total population achieved a V̇O2 plateau and 75% a RERpeak > 1.0. The HR and BLC criteria were met by 19% and 22%, respectively. T-test results revealed significant differences between adolescents with MDD and control values for all outcomes. Adolescents with MDD achieved between 56% and 83% of control values.   Conclusions: The study shows that compared with control values, fewer adolescents with MDD achieve the exhaustion criteria on a CPET and adolescents with MDD have significantly lower cardiorespiratory fitness.   Clinical trial registration: No. U1111-1145–1854. What is Known:• It is already known that endurance training has a positive effect on depressive symptoms. What is New:• A relevant proportion of adolescents with major depressive disorder do not achieve their V̇O2max during a graded cardiopulmonary exercise test.• Adolescents with major depressive disorder have significantly lower cardiorespiratory fitness compared to sex- and age-related control values. }}, author = {{Wenzel, Charlotte and Bongers, Bart Chateau and Schlagheck, Marit Lea and Reis, Daniela and Reinhard, Franziska and Schmidt, Peter and Bernitzki, Stefan and Oberste, Max and Wunram, Heidrun Lioba and Zimmer, Philipp and Fricke, Oliver}}, issn = {{1432-1076}}, journal = {{European Journal of Pediatrics}}, number = {{1}}, pages = {{379--388}}, publisher = {{Springer Science and Business Media LLC}}, title = {{{Validation of the maximal cardiopulmonary exercise test in adolescents with major depressive disorder and comparison of cardiorespiratory fitness with sex- and age-related control values}}}, doi = {{10.1007/s00431-023-05304-6}}, volume = {{183}}, year = {{2023}}, } @article{64045, abstract = {{Abstract In this work, we report on an improved cell assembly of cylindrical electrochemical cells for 23Na in-situ solid-state NMR (ssNMR) investigations. The cell set-up is suitable for using powder electrode materials. Reproducibility of our cell assembly is analyzed by preparing two cells containing hard carbon (HC) powder as working electrode and sodium metal as reference electrode. Electrochemical storage properties of HC powder electrode derived from carbonization of sustainable cellulose are studied by ssNMR. 23Na in-situ ssNMR monitors the sodiation/desodiation of a Na{\textbar}NaPF6{\textbar}HC cell (cell 1) over a period of 22?days, showing high cell stability. After the galvanostatic process, the HC powder material is investigated by high resolution 23Na ex-situ MAS NMR. The formation of ionic sodium species in different chemical environments is obtained. Subsequently, a second Na{\textbar}NaPF6{\textbar}HC cell (cell 2) is sodiated for 11?days achieving a capacity of 220?mAh/g. 23Na ex-situ MAS NMR measurements of the HC powder material extracted from this cell clearly indicate the presence of quasi-metallic sodium species next to ionic sodium species. This observation of quasi-metallic sodium species is discussed in terms of the achieved capacity of the cell as well as of side reactions of sodium in this electrode material.}}, author = {{Šić, Edina and Schutjajew, Konstantin and Haagen, Ulrich and Breitzke, Hergen and Oschatz, Martin and Buntkowsky, Gerd and Gutmann, Torsten}}, issn = {{1864-5631}}, journal = {{Chemsuschem}}, keywords = {{solid-state nmr, hard carbon, electrochemical cells, in-situ characterization, sodium}}, pages = {{e202301300}}, publisher = {{John Wiley & Sons, Ltd}}, title = {{{Electrochemical Sodium Storage in Hard Carbon Powder Electrodes Implemented in an Improved Cell Assembly: Insights from In-Situ and Ex-Situ Solid-State NMR}}}, doi = {{10.1002/cssc.202301300}}, volume = {{17}}, year = {{2023}}, } @article{61252, abstract = {{AbstractThe biexciton‐exciton emission cascade commonly used in quantum‐dot systems to generate polarization entanglement yields photons with intrinsically limited indistinguishability. In the present work, it focuses on the generation of pairs of photons with high degrees of polarization entanglement and simultaneously high indistinguishability. It achieves this goal by selectively reducing the biexciton lifetime with an optical resonator. It demonstrates that a suitably tailored circular Bragg reflector fulfills the requirements of sufficient selective Purcell enhancement of biexciton emission paired with spectrally broad photon extraction and twofold degenerate optical modes. The in‐depth theoretical study combines (i) the optimization of realistic photonic structures solving Maxwell's equations from which model parameters are extracted as input for (ii) microscopic simulations of quantum‐dot cavity excitation dynamics with full access to photon properties. It reports non‐trivial dependencies on system parameters and use the predictive power of the combined theoretical approach to determine the optimal range of Purcell enhancement that maximizes indistinguishability and entanglement to near unity values, here specifically for the telecom C‐band at 1550 nm.}}, author = {{Bauch, David and Siebert, Dustin and Jöns, Klaus D. and Förstner, Jens and Schumacher, Stefan}}, issn = {{2511-9044}}, journal = {{Advanced Quantum Technologies}}, number = {{1}}, publisher = {{Wiley}}, title = {{{On‐Demand Indistinguishable and Entangled Photons Using Tailored Cavity Designs}}}, doi = {{10.1002/qute.202300142}}, volume = {{7}}, year = {{2023}}, } @article{63043, abstract = {{Spatial modes of light have become highly attractive to increase the dimension and, thereby, security and information capacity in quantum key distribution (QKD). So far, only transverse electric field components have been considered, while longitudinal polarization components have remained neglected. Here, we present an approach to include all three spatial dimensions of electric field oscillation in QKD by implementing our tunable, on-a-chip vector beam decoder (VBD). This inversely designed device pioneers the "preparation" and "measurement" of three-dimensionally polarized mutually unbiased basis states for high-dimensional (HD) QKD and paves the way for the integration of HD QKD with spatial modes in multifunctional on-a-chip photonics platforms.}}, title = {{{Tunable vector beam decoder by inverse design for high-dimensional quantum key distribution with 3D polarized spatial modes}}}, doi = {{10.48550/ARXIV.2304.12296}}, year = {{2023}}, } @article{57556, abstract = {{AbstractMathematical modelling emphasizes the connection between mathematics and reality — still, tasks are often exclusively introduced inside the classroom. The paper examines the potential of different task settings for mathematical modelling with real objects: outdoors at the real object itself, with photographs and with a 3D model representation. It is the aim of the study to analyze how far the mathematical modelling steps of students solving the tasks differ in comparison to the settings and representations. In a qualitative study, 19 lower secondary school students worked on tasks of all three settings in a Latin square design. Their working processes in the settings are compared with a special focus on the modelling steps Simplifying and Structuring, as well as Mathematizing. The analysis by means of activity diagrams and a qualitative content analysis shows that both steps are particularly relevant when students work with real objects — independent from the three settings. Still, differences in the actual activities could be observed in the students’ discussion on the appropriateness of a model and in dealing with inaccuracies at the real object. In addition, the process of data collection shows different procedures depending on the setting which presents each of them as an enrichment for the acquisition of modelling skills.}}, author = {{Jablonski, Simone}}, issn = {{0013-1954}}, journal = {{Educational Studies in Mathematics}}, number = {{2}}, pages = {{307--330}}, publisher = {{Springer Science and Business Media LLC}}, title = {{{Is it all about the setting? — A comparison of mathematical modelling with real objects and their representation}}}, doi = {{10.1007/s10649-023-10215-2}}, volume = {{113}}, year = {{2023}}, } @article{57558, abstract = {{AbstractMathematical modelling emphasizes the connection between mathematics and reality — still, tasks are often exclusively introduced inside the classroom. The paper examines the potential of different task settings for mathematical modelling with real objects: outdoors at the real object itself, with photographs and with a 3D model representation. It is the aim of the study to analyze how far the mathematical modelling steps of students solving the tasks differ in comparison to the settings and representations. In a qualitative study, 19 lower secondary school students worked on tasks of all three settings in a Latin square design. Their working processes in the settings are compared with a special focus on the modelling steps Simplifying and Structuring, as well as Mathematizing. The analysis by means of activity diagrams and a qualitative content analysis shows that both steps are particularly relevant when students work with real objects — independent from the three settings. Still, differences in the actual activities could be observed in the students’ discussion on the appropriateness of a model and in dealing with inaccuracies at the real object. In addition, the process of data collection shows different procedures depending on the setting which presents each of them as an enrichment for the acquisition of modelling skills.}}, author = {{Jablonski, Simone}}, issn = {{0013-1954}}, journal = {{Educational Studies in Mathematics}}, number = {{2}}, pages = {{307--330}}, publisher = {{Springer Science and Business Media LLC}}, title = {{{Is it all about the setting? — A comparison of mathematical modelling with real objects and their representation}}}, doi = {{10.1007/s10649-023-10215-2}}, volume = {{113}}, year = {{2023}}, } @article{47009, abstract = {{We present a fully integrated radio frequency identifications transponder chip operating at 5.8 GHz, which is compatible with the class-1 generation-2 of the Electronic Product Code protocol (EPC-C1 G2). The tag chip including the analog front-end and the digital baseband processor, are designed in the sub-threshold regime (0.5 V) with a total supply current of less than 50 μA. As a power scavenging unit, a single-stage differential-drive rectifier structure is designed and fabricated with standard threshold voltage (SVT) MOS elements in a commercial 65-nm CMOS process, to provide 0.8 V of rectified voltage. Measurements performed on the fabricated single-stage structure show a maximum power conversion efficiency of 69.6% for a 22 kΩ load and a sensitivity of -12.5 dBm, which corresponds to more than 1 m of reading range. The power conversion efficiency at this range is about 64%.}}, author = {{Haddadian, Sanaz and Scheytt, J. Christoph and von Bögel, Gerd and Grenter, Thorben}}, issn = {{2469-7281}}, journal = {{ IEEE Journal of Radio Frequency Identification}}, publisher = {{IEEE}}, title = {{{A Sub-Threshold Microwave RFID Tag Chip, Compatible With RFID MIMO Reader Technology}}}, doi = {{10.1109/JRFID.2023.3308332}}, year = {{2023}}, } @phdthesis{58680, abstract = {{Heutige On-Board-Ladewandler sind typischerweise aus zwei Stufen aufgebaut, die über einen Spannungszwischenkreis verbunden sind. Als erste Stufe kommt ein PFC-Gleichrichter zum Einsatz, der die Anforderungen an den Netzstrom bezüglich Oberschwingungsgehalt und Leistungsfaktor sicherstellt. Für die zweite Wandler-Stufe hat sich in den vergangenen Jahren ein LLC-Resonanzwandler qualifiziert, der die Ladeleistung an die Traktionsbatterie galvanisch getrennt überträgt. Der Zwischenkreis besteht aus einer Bank von Elektrolytkondensatoren, in denen die pulsierende Eingangsleistung zwischengespeichert wird. Die Kondensatoren machen einen erheblichen Teil des Lader-Volumens aus und altern schnell, was insbesondere für Ladewandler an Bord von Elektrofahrzeugen unerwünscht ist. In der vorliegenden Arbeit wird untersucht, ob diese zweistufige Struktur verworfen werden kann, indem der LLC-Resonanzwandler direkt an die gleichgerichtete Netzspannung angeschlossen wird.Zum Einsatz des LLC-Resonanzwandlers als einstufiger Ladewandler ist die Schaltung für einen großen Strom- und Spannungsbereich auszulegen. Hierfür wird in der vorliegenden Arbeit eine erweiterte Zeitbereichsanalyse erarbeitet, deren hohe Modellierungsgenauigkeit im Anschluss experimentell nachgewiesen wird. Mit Hilfe dieser Zeitbereichsanalyse werden die Belastungsgrößen des Resonanzwandlers berechnet, um hiermit eine Vorauswahl der Schaltungsparameter treffen zu können. Darauf aufbauend erfolgt die Optimierung des integrierten Transformators als Schlüsselkomponente des Ladewandlers sowie dessen prototypische Realisierung. Abschließend wird mittels Prototypen die erzielbare Leistungsdichte ermittelt. Ergebnis: Verglichen mit etablierten Ladewandlern der heutigen Elektrofahrzeuge konnte durch den einstufigen Ansatz die Leistungsdichte um ca. 53% gesteigert werden.}}, author = {{Keuck, Lukas}}, publisher = {{LibreCat University}}, title = {{{Entwurf eines einstufigen Ladewandlers auf Basis eines LLC-Resonanzwandlers}}}, doi = {{10.17619/UNIPB/1-1727}}, year = {{2023}}, } @inproceedings{46426, abstract = {{One of the main challenges for next generation automotive radars is the improvement of angular resolution to a sub-degree level. In this context, wide aperture automotive radars of 1m length or more and resolution close to 0.1° in azimuth and 0.5° in elevation could be beneficial. To enable coherent processing of arrays with such large aperture, prior (i.e offline) and online calibration are necessary: channel imbalances (gains and phases) and three dimensional coordinates of transmit and receive elements need to be determined. We propose a calibration strategy based on alternating steps between the two subtasks of i) channel imbalance estimation with ‘known’ array positions, by applying a singular value decomposition to the resulting tensor calculus problem; and ii) antenna position estimation with ’known’ channel imbalances, by numerically maximizing the Bayesian posterior probability; in both cases operating on range/Doppler snapshots of disjoint targets (with potentially unknown locations). Simulation studies based on the parameters of a MIMO 8x6 linear sparse array show promising results as long as the initial position errors do not exceed half a wavelength (2mm), beyond which we observe strong effects of ambiguity. Experimental results with real measurements show that after calibration in laboratory conditions, our MIMO 8x6 demonstrator with 50cm aperture is able to resolve two targets at the same range with angular separation at least as close as 0.4°.}}, author = {{Greiff, Christian and Mateos-Núñez, David and Simoni, Renato and González-Huici, Maria and Kruse, Stephan and Scheytt, J. Christoph and Kolk, Karl and Höller, Christian and Kurz, Heiko Gustav and Meinecke, Marc-Michael and Gisder, Thomas}}, booktitle = {{2023 24th International Radar Symposium (IRS)}}, location = {{Berlin, Germany}}, publisher = {{IEEE}}, title = {{{Calibration of Large Coherent MIMO Radar Arrays: Channel Imbalances and 3D Antenna Positions}}}, doi = {{10.23919/IRS57608.2023.10172475}}, year = {{2023}}, } @inproceedings{47064, author = {{Iftekhar, Mohammed and Nagaraju, Harshan and Kneuper, Pascal and Sadiye, Babak and Müller, Wolfgang and Scheytt, J. Christoph}}, booktitle = {{BCICTS 2023 IEEE BiCMOS and Compound Semiconductor Integrated Circuits and Technology Symposium}}, location = {{MONTEREY, CALIFORNIA, USA}}, title = {{{A 28-Gb/s 27.2 mW NRZ Full-Rate Bang-Bang Clock and Data Recovery in 22 nm FD-SOI CMOS Technology }}}, year = {{2023}}, } @article{60355, abstract = {{We present a method for the generation of higher-order tetrahedral meshes. In contrast to previous methods, the curved tetrahedral elements are guaranteed to be free of degeneracies and inversions while conforming exactly to prescribed piecewise polynomial surfaces, such as domain boundaries or material interfaces. Arbitrary polynomial order is supported. Algorithmically, the polynomial input surfaces are first covered by a single layer of carefully constructed curved elements using a recursive refinement procedure that provably avoids degeneracies and inversions. These tetrahedral elements are designed such that the remaining space is bounded piecewise linearly. In this way, our method effectively reduces the curved meshing problem to the classical problem of linear mesh generation (for the remaining space).}}, author = {{Khanteimouri, Payam and Campen, Marcel}}, issn = {{0730-0301}}, journal = {{ACM Transactions on Graphics}}, number = {{6}}, pages = {{1--19}}, publisher = {{Association for Computing Machinery (ACM)}}, title = {{{3D Bézier Guarding: Boundary-Conforming Curved Tetrahedral Meshing}}}, doi = {{10.1145/3618332}}, volume = {{42}}, year = {{2023}}, } @article{60354, abstract = {{We present a set of operators to perform modifications, in particular collapses and splits, in volumetric cell complexes which are discretely embedded in a background mesh. Topological integrity and geometric embedding validity are carefully maintained. We apply these operators strategically to volumetric block decompositions, so-called T-meshes or base complexes, in the context of hexahedral mesh generation. This allows circumventing the expensive and unreliable global volumetric remapping step in the versatile meshing pipeline based on 3D integer-grid maps. In essence, we reduce this step to simpler local cube mapping problems, for which reliable solutions are available. As a consequence, the robustness of the mesh generation process is increased, especially when targeting coarse or block-structured hexahedral meshes. We furthermore extend this pipeline to support feature alignment constraints, and systematically respect these throughout, enabling the generation of meshes that align to points, curves, and surfaces of special interest, whether on the boundary or in the interior of the domain.}}, author = {{Brückler, Hendrik and Campen, Marcel}}, issn = {{0730-0301}}, journal = {{ACM Transactions on Graphics}}, number = {{6}}, pages = {{1--24}}, publisher = {{Association for Computing Machinery (ACM)}}, title = {{{Collapsing Embedded Cell Complexes for Safer Hexahedral Meshing}}}, doi = {{10.1145/3618384}}, volume = {{42}}, year = {{2023}}, } @article{60335, abstract = {{A method is presented to compute volumetric maps and parametrizations of objects over 3D domains. As a key feature, continuity and bijectivity are ensured by construction. Arbitrary objects of ball topology, represented as tetrahedral meshes, are supported. Arbitrary convex as well as star-shaped domains are supported. Full control over the boundary mapping is provided. The method is based on the technique of simplicial foliations, generalized to a broader class of domain shapes and applied adaptively in a novel localized manner. This increases flexibility as well as efficiency over the state of the art, while maintaining reliability in guaranteeing map bijectivity.}}, author = {{Hinderink, Steffen and Campen, Marcel}}, issn = {{0730-0301}}, journal = {{ACM Transactions on Graphics}}, number = {{4}}, pages = {{1--16}}, publisher = {{Association for Computing Machinery (ACM)}}, title = {{{Galaxy Maps: Localized Foliations for Bijective Volumetric Mapping}}}, doi = {{10.1145/3592410}}, volume = {{42}}, year = {{2023}}, } @inproceedings{48012, abstract = {{3D printing is a well-established technology with rapidly increasing usage scenarios both in the industry and consumer context. The growing popularity of 3D printing has also attracted security researchers, who have analyzed possibilities for weakening 3D models or stealing intellectual property from 3D models. We extend these important aspects and provide the first comprehensive security analysis of 3D printing data formats. We performed our systematic study on the example of the 3D Manufacturing Format (3MF), which offers a large variety of features that could lead to critical attacks. Based on 3MF’s features, we systematized three attack goals: Data Exfiltration (dex), Denial of Service, and UI Spoofing (uis). We achieve these goals by exploiting the complexity of 3MF, which is based on the Open Packaging Conventions (OPC) format and uses XML to define 3D models. In total, our analysis led to 352 tests. To create and run these tests automatically, we implemented an open-source tool named 3MF Analyzer (tool), which helped us evaluate 20 applications.}}, author = {{Rossel, Jost and Mladenov, Vladislav and Somorovsky, Juraj}}, booktitle = {{Proceedings of the 26th International Symposium on Research in Attacks, Intrusions and Defenses}}, keywords = {{Data Format Security, 3D Manufacturing Format, 3D Printing, Additive Manufacturing}}, location = {{Hongkong}}, publisher = {{ACM}}, title = {{{Security Analysis of the 3MF Data Format}}}, doi = {{10.1145/3607199.3607216}}, year = {{2023}}, }