TY - JOUR A1 - Himmelstoss, Felix T1 - Third order converters with current output for driving LEDs JF - WSEAS Transactions on Power Systems KW - DC/DC converters KW - current output KW - limited duty cycle converter KW - simulation KW - modeling Y1 - U6 - http://dx.doi.org/10.37394/232016.2022.17.40 VL - Volume 17 SP - 402 EP - 409 ER - TY - CHAP A1 - Veigl, Christoph A1 - Klaus, Benjamin A1 - Aigner, Benjamin A1 - Wagner, Manuel T1 - Universal Access Panel: A Novel Approach for Accessible Smart Homes and IoT T2 - Computers Helping People with Special Needs / Proceedings of the 18th International Conference ICCHP-AAATE 2022, July 11-15, 2022, Lecco, Italy N2 - Although various standards and guidelines for accessible design exist, many modern digital devices lack even basic accessibility features. In particular, touchscreens without haptic feedback and a highly complex menu navigation impose serious hurdles for many people – especially for people with disabilities and elderly persons. In this work, we present the Universal Access Panel (UAP) for enabling barrier-free access to home appliances and IoT devices. The system offers a novel, radically simple, multimodal user interface consisting of just a few interaction elements for accessing dedicated functions of the connected home. Using established APIs and communication protocols such as HomeConnect or OpenHab, various domestic appliances, consumer products and smart home devices can be controlled from a single, multimodal interaction console. The system has been designed in cooperation with visually impaired accessibility experts and a user study was conducted with people from the target group. The results show a high overall usability of the prototype. KW - Home Appliances KW - Accessibility KW - Multimodal User Interface KW - Smart Homes KW - Internet-of-Things Y1 - U6 - http://dx.doi.org/https://doi.org/10.1007/978-3-031-08645-8_18 SP - 148 EP - 158 ER - TY - CHAP A1 - Himmelstoss, Felix A1 - Windisch, Michael T1 - Tapped inductor Boost with exploitation of the stray energy T2 - Proceedings of 2022 IEEE 20th International Power Electronics and Motion Control Conference (PEMC 2022), Brasov, Rumania, Sep. 25-29 N2 - Tapped inductor DC-to-DC converters are interesting circuits, the winding ratio of the two windings mounted on the same core change the voltage transformation ratio compared to the untapped inductor. The tapped inductor converters are especially useful, when high or low voltage transformation ratios have to be realized. The disadvantage of this concept is that the coupling between the two windings is not total and can be described by the stray or leakage inductance. This stray inductance leads to a high overvoltage at the active switch, and therefore also across other elements of the converter. After a short summery of the ideal tapped Boost converter, the design of an RCD snubber which limits the overvoltage is explained. To improve the efficiency of the converter two active snubber networks are treated, which feed the energy stored in the snubber capacitor into the input source or into the output circuit. Simulations are used to prove these considerations. KW - DC/DC converter KW - stray inductance KW - recuperation KW - active snubber Y1 - U6 - http://dx.doi.org/10.1109/PEMC51159.2022.9962849 SP - 75 EP - 80 ER - TY - CHAP A1 - Himmelstoss, Felix A1 - Votzi, Helmut T1 - Two-Stage Step-up Converter with Different Voltage Transformation Ratios depending on the Duty Cycle T2 - 20th International Conference on Renewable Energies and Power Quality (ICREPQ’22) Vigo (Spain), 27th to 29th July 2022 N2 - A two-stage converter with high output voltage ratio and reduced current stress of the inductors and partly reduced voltage stress is discussed. The function is explained with the help of voltage and current diagrams. The voltage transformation ratio changes between a quadratic step-up for duty cycles lower 0.5 and a double Boost converter for duty cycles higher than 0.5. Dimensioning hints, the control law for feed-forward controls, the transient when the supply is turned on is discussed and some simulations are given. A comparison to other two-stage converters is also treated. KW - Quadratic boost KW - double boost converter KW - feed-forward control KW - start-up Y1 - U6 - http://dx.doi.org/10.24084/repqj20.218 VL - Vol. 20 SP - 66 ER - TY - GEN A1 - Friedrich, Robin A1 - Lakic, Nevana A1 - Prähauser, Linda A1 - Schweitzer, Karoline A1 - Olscher, Christoph A1 - Monforte Vila, Xavier A1 - Leitner, Rita A1 - Gepp, Barbara T1 - Effects of Plastic on the Freshwater Snail Biomphalaria Glabrata T2 - SETAC Europe 32nd Annual Meeting in Copenhagen, Denmark from 15 - 19. May 2022 KW - Ecotoxicology KW - Biomphalaria Glabrata Y1 - ER - TY - CHAP A1 - Himmelstoss, Felix T1 - Cascaded control of a Buck converter designed and simulated with the help of LTSpice T2 - 6th International European Congress on Interdisciplinary Scientific Research, Aug. 26-27, 2022, Bukarest, Rumania KW - education KW - power electronics converters KW - Buck converter KW - two-loop control KW - cascade control Y1 - SP - 1086 EP - 1096 ER - TY - CHAP A1 - Himmelstoss, Felix A1 - Edelmoser, Karl T1 - Liquid and surface disinfection with pulsed UVC LEDs T2 - 2nd Ahi Evran International Conference on Scientific Research, Kirshehir, Turkey, October 21-23, 2022 KW - disinfection KW - light emitting diode KW - ultraviolet UV light KW - pulsed power KW - DC/DC Converter Y1 - SP - 654 EP - 664 ER - TY - CHAP A1 - Himmelstoss, Felix A1 - Yaman, Ferhat A1 - Edelmoser, Karl T1 - Building block for a spot welder T2 - International Congress on Innovation Technologies & Engineering, Sept. 2-4, 2022, Izmir, Turkey, pp. 139-148 KW - spot welding KW - capacitor charging KW - pulse power KW - retrofit Y1 - SP - 139 EP - 148 ER - TY - CHAP A1 - Himmelstoss, Felix T1 - Concept to change the voltage transformation ratio of a DC/DC converter T2 - Cukurova 9th International Scientific Researches Conference, Oct. 9-11, 2022, Adana, Turkey, pp. 258-273 KW - DC/DC converter KW - AC-Switch KW - voltage transformation ratio KW - modeling KW - simulation Y1 - SP - 258 EP - 273 ER - TY - CHAP A1 - Himmelstoss, Felix T1 - Three DC/DC Converters with continuous input and output current for LED applications T2 - International Conference on Engineering Sciences ICES, Baku, Azerbeijan, Nov. 11-12, 2022 KW - DC/DC converter KW - current control KW - efficiency KW - lighting Y1 - SP - 335 EP - 347 ER - TY - CHAP A1 - Himmelstoß, Felix T1 - Controller design of a Buck converter with the help of LTSpice T2 - Proceedings of the International Asian Congress of Contemporary Sciences, 27-29 May, 2022, Van, Turkiye KW - DC/DC converter KW - Buck converter KW - feedforward KW - compensation controller KW - simulation Y1 - SP - 195 EP - 202 ER - TY - CHAP A1 - Angel, Nikolaus A1 - Orsolits, Horst A1 - Garcia, Jose T1 - Developing an AR Based Tool for Teaching Motion Analysis on Assembly Tasks T2 - 2022 8th International Conference of the Immersive Learning Research Network (iLRN), 2022 N2 - Engineering education courses look into processes, equipment and people in order to prepare students to tackle problems in their careers. In manufacturing industry, it is important to use virtual manufacturing tools to analyse processes. This includes both equipment and people. Assembly operations can involve human operators. Modular arrangements of predetermined time standards MODAPTS is a predetermined motion time system method used to analyse assembly processes. Augmented reality (AR) is increasingly being used for industrial processes as well as in education. AR application have been used for maintenance training as a useful way to overly digital instructions to a trainee whilst being able to look at a real object. This is potential beneficial for education. This paper presents the evaluation of a prototype to test a predetermined time standards model using an AR application. An evaluation was carried out comparing AR-based instructions in tablet and PC monitor and paper-written instructions. The results of evaluating the prototype encourage their use as an educational tool in engineering courses. KW - Augmented Reality KW - Education Technology KW - Virtual Engineering KW - Assembly Assistance Y1 - SN - 978-1-7348-9952-8 U6 - http://dx.doi.org/10.23919/iLRN55037.2022.9815914 ER - TY - GEN A1 - Nemec, Iris A1 - Frohner, Matthias T1 - How can life science students, especially biomedical engineering students, benefit from the extra-curricular offerings and systems already established in other scientific fields? T2 - Abstracts of the 2022 Joint Annual Conference of the Austrian (ÖGBMT), German (VDE DGBMT) and Swiss (SSBE) Societies for Biomedical Engineering, including the 14th Vienna International Workshop on Functional Electrical Stimulation KW - extra-curricular offerings KW - education Y1 - U6 - http://dx.doi.org/https://doi.org/10.1515/bmt-2022-2001 SP - 348 ER - TY - GEN A1 - Traxler, Lukas A1 - Balz, Andrea T1 - Current Advances in the Optical Characterization of Intraocular Lenses T2 - Abstracts of the 2022 Joint Annual Conference of the Austrian (ÖGBMT), German (VDE DGBMT) and Swiss (SSBE) Societies for Biomedical Engineering, including the 14th Vienna International Workshop on Functional Electrical Stimulation KW - Intraocular Lenses Y1 - U6 - http://dx.doi.org/https://doi.org/10.1515/bmt-2022-2001 SP - 102 ER - TY - JOUR A1 - Ashmwe, Mohamed A1 - Posa, Katja A1 - Rührnößl, Alexander A1 - Heinzel, Johannes Christoph A1 - Heimel, Patrick A1 - Mock, Michael A1 - Schädl, Barbara A1 - Keibl, Claudia A1 - Couillard-Despres, Sebastien A1 - Redl, Heinz A1 - Mittermayr, Rainer A1 - Hercher, David T1 - Effects of Extracorporeal Shockwave Therapy on Functional Recovery and Circulating miR-375 and miR-382-5p after Subacute and Chronic Spinal Cord Contusion Injury in Rats JF - Biomedicines N2 - Extracorporeal shockwave therapy (ESWT) can stimulate processes to promote regeneration, including cell proliferation and modulation of inflammation. Specific miRNA expression panels have been established to define correlations with regulatory targets within these pathways. This study aims to investigate the influence of low-energy ESWT-applied within the subacute and chronic phase of SCI (spinal cord injury) on recovery in a rat spinal cord contusion model. Outcomes were evaluated by gait analysis, µCT and histological analysis of spinal cords. A panel of serum-derived miRNAs after SCI and after ESWT was investigated to identify injury-, regeneration- and treatment-associated expression patterns. Rats receiving ESWT showed significant improvement in motor function in both a subacute and a chronic experimental setting. This effect was not reflected in changes in morphology, µCT-parameters or histological markers after ESWT. Expression analysis of various miRNAs, however, revealed changes after SCI and ESWT, with increased miR-375, indicating a neuroprotective effect, and decreased miR-382-5p potentially improving neuroplasticity via its regulatory involvement with BDNF. We were able to demonstrate a functional improvement of ESWT-treated animals after SCI in a subacute and chronic setting. Furthermore, the identification of miR-375 and miR-382-5p could potentially provide new targets for therapeutic intervention in future studies. KW - Tissue Engineering KW - ESWT KW - Spinal Cord Injury Y1 - U6 - http://dx.doi.org/https://doi.org/10.3390/biomedicines10071630 VL - 2022 IS - 10(7) SP - 1630 ER - TY - JOUR A1 - Bernhard, Jonathan C A1 - Marolt Presen, Darja A1 - Li, Ming A1 - Monforte, Xavier A1 - Ferguson, James A1 - Leinfellner, Gabriele A1 - Heimel, Patrick A1 - Betti, Susanne L A1 - Shu, Sharon A1 - Teuschl-Woller, Andreas H A1 - Tangl, Stefan A1 - Redl, Heinz A1 - Vunjak-Novakovic, Gordana T1 - Effects of Endochondral and Intramembranous Ossification Pathways on Bone Tissue Formation and Vascularization in Human Tissue-Engineered Grafts JF - Cells N2 - Bone grafts can be engineered by differentiating human mesenchymal stromal cells (MSCs) via the endochondral and intramembranous ossification pathways. We evaluated the effects of each pathway on the properties of engineered bone grafts and their capacity to drive bone regeneration. Bone-marrow-derived MSCs were differentiated on silk scaffolds into either hypertrophic chondrocytes (hyper) or osteoblasts (osteo) over 5 weeks of in vitro cultivation, and were implanted subcutaneously for 12 weeks. The pathways' constructs were evaluated over time with respect to gene expression, composition, histomorphology, microstructure, vascularization and biomechanics. Hypertrophic chondrocytes expressed higher levels of osteogenic genes and deposited significantly more bone mineral and proteins than the osteoblasts. Before implantation, the mineral in the hyper group was less mature than that in the osteo group. Following 12 weeks of implantation, the hyper group had increased mineral density but a similar overall mineral composition compared with the osteo group. The hyper group also displayed significantly more blood vessel infiltration than the osteo group. Both groups contained M2 macrophages, indicating bone regeneration. These data suggest that, similar to the body's repair processes, endochondral pathway might be more advantageous when regenerating large defects, whereas intramembranous ossification could be utilized to guide the tissue formation pattern with a scaffold architecture. KW - bone tissue engineering KW - endochondral KW - mesenchymal stromal cells KW - ossification KW - intramembranous Y1 - U6 - http://dx.doi.org/10.3390/cells11193070 VL - 11 IS - 19:3070 ER - TY - JOUR A1 - Romanelli, Pasquale A1 - Bieler, Lara A1 - Heimel, Patrick A1 - Škokić, Siniša A1 - Jakubecova, Dominika A1 - Kreutzer, Christina A1 - Zaunmair, Pia A1 - Smolčić, Tomislav A1 - Benedetti, Bruno A1 - Rohde, Eva A1 - Gimona, Mario A1 - Hercher, David A1 - Dobrivojević Radmilović, Marina A1 - Couillard-Despres, Sebastien T1 - Enhancing Functional Recovery Through Intralesional Application of Extracellular Vesicles in a Rat Model of Traumatic Spinal Cord Injury JF - Front Cell Neurosci N2 - Local inflammation plays a pivotal role in the process of secondary damage after spinal cord injury. We recently reported that acute intravenous application of extracellular vesicles (EVs) secreted by human umbilical cord mesenchymal stromal cells dampens the induction of inflammatory processes following traumatic spinal cord injury. However, systemic application of EVs is associated with delayed delivery to the site of injury and the necessity for high doses to reach therapeutic levels locally. To resolve these two constraints, we injected EVs directly at the lesion site acutely after spinal cord injury. We report here that intralesional application of EVs resulted in a more robust improvement of motor recovery, assessed with the BBB score and sub-score, as compared to the intravenous delivery. Moreover, the intralesional application was more potent in reducing inflammation and scarring after spinal cord injury than intravenous administration. Hence, the development of EV-based therapy for spinal cord injury should aim at an early application of vesicles close to the lesion. KW - exosomes KW - inflammation KW - locomotion KW - neuroimaging KW - motor function Y1 - U6 - http://dx.doi.org/10.3389/fncel.2021.795008 VL - 15 ER - TY - JOUR A1 - Feichtinger, Xaver A1 - Heimel, Patrick A1 - Tangl, Stefan A1 - Keibl, Claudia A1 - Nürnberger, Sylvia A1 - Schanda, Jakob Emanuel A1 - Hercher, David A1 - Kocijan, Roland A1 - Redl, Heinz A1 - Grillari, Johannes A1 - Fialka, Christian A1 - Mittermayr, Rainer T1 - Improved biomechanics in experimental chronic rotator cuff repair after shockwaves is not reflected by bone microarchitecture JF - PLoS One KW - chronic rotator cuff repair KW - bone microarchitecture Y1 - U6 - http://dx.doi.org/10.1371/journal.pone.0262294 VL - 17 IS - 1 ER - TY - JOUR A1 - Ahlborn, Felix A1 - Kupka, Friedrich A1 - Weiss, Achim A1 - Flaskamp, Martin T1 - Stellar evolution models with overshooting based on 3-equation non-local theories: II. Main sequence models of A- and B-type stars JF - Astronomy & Astrophysics KW - convection KW - turbulence KW - stars: evolution KW - stars: interiors Y1 - U6 - http://dx.doi.org/https://doi.org/10.1051/0004-6361/202243126 IS - Volume 667 SP - Article Number A97 ER - TY - JOUR A1 - Kupka, Friedrich A1 - Ahlborn, Felix A1 - Weiss, Achim T1 - Stellar evolution models with overshooting based on 3-equation non-local theories: I. Physical basics and the computation of the dissipation rate JF - Astronomy & Astrophysics KW - convection KW - turbulence KW - stars: evolution KW - stars: interiors Y1 - U6 - http://dx.doi.org/https://doi.org/10.1051/0004-6361/202243125 IS - Volume 667 SP - Article Number A96 ER -