12828 research outputs found
Sort by
IEEE Sensors Letters / Design and Fabrication of Flexible Thin-Wire Multispot Thermocouples Using Hot-Wire Coating
No full textMeccanica / Vibrations of a piezoelectric Timoshenko beam with resistive-inductive electrodes
No full textAbstract This paper presents a one-dimensional theory for moderately thick piezoelectric beam-type structures with imperfect resistive electrodes. For practical applications, a special goal is also the finite element discretization of the electromechanically coupled partial differential equations, which combine the Telegrapher’s equations with the elastic properties of a Timoshenko beam. Unlike ideal electrodes, which satisfy the equipotential area condition, the voltage distribution in resistive electrodes is governed by the diffusion equation. For the electrical domain, Kirchhoff’s voltage and current rules are applied to derive the parabolic differential equation, which is driven by the time derivative of the axial strain. It is demonstrated that the current flow through the electrodes of the piezoelectric layer depends on the electrode resistance and the capacitance. For the mechanical domain, d’Alembert’s principle is combined with the piezoelectric constitutive equations to derive an extended version of the Timoshenko beam equations, incorporating the x -dependent voltage drop across the electrodes. A one-dimensional finite element is then formulated using Timoshenko shape functions for the deflection and the rotation angle, along with linear shape functions for the voltage drop along the beam segment. For the validation of the model a clamped-hinged piezoelectric beam is used as a benchmark example to compare the results of the one-dimensional discretization with two-dimensional finite element (FE) simulations. Various types of resistive electrodes are considered, including static deflections, dynamic vibrations, and eigenfrequency analyses. The results demonstrate that the derived piezoelectric beam model also includes the case of ideal electrodes (short- and open-circuited), when the sheet resistance is very low, and the case of a non-electroded piezoelectric beam, when the sheet resistance is very high.Austrian Science Fund 10.55776/P3330
Technology and Disability / Assistive technology using artificial intelligence in the long-term care sector for persons with disabilities: A systematic literature review
No full textAssistive technology (AT) and artificial intelligence (AI) are topics that are becoming increasingly important in the context of long-term care (LTC). The literature discusses various so-called intelligent assistive technologies (IATs) in relation to persons with disabilities, people with chronic diseases and people with mental health problems. These technologies aim to improve the quality of life of those affected. The aim of this paper is to provide an overview of IATs used by service users in the LTC sector and to identify emerging issues related to the use of these technologies. To achieve this, a systematic literature review was conducted. The findings show that IATs are increasingly recognized for their role in enhancing quality of life for users and supporting caregivers in LTC, but their deployment raises critical issues such as ethics, privacy, and responsible innovation. The literature highlights the need for updated policies to address technical, regulatory, and practical challenges, while also identifying gaps in long-term impact research and technology integration strategies.Erasmus+ 10114026
Computers and Education Open / The Why and How prospective mathematics teachers want to employ digital mathematics tools in classrooms
No full textKI-VO: biometrische Überwachungssysteme und das Grundrecht auf Privatsphäre
No full textMit 1. August 2024 ist die KI-VO in Kraft getreten und wird in den kommenden drei Jahren stufenweise in vollem Umfang ihre Anwendbarkeit entfalten. Erklärtes Ziel ist unter anderem die Grundrechte zu schützen, die durch den Einsatz von Künstlicher Intelligenz in Gefahr geraten könnten. Es drängt sich daher die Frage auf, ob die KI-VO ihrem Zweck gem Art 1 KI-VO nachkommt oder unklare Formulierungen und rechtliche Grauzonen die Einhaltung der Grundrechte zu wenig garantieren. Immerhin warnten Datenschutzexpert:innen zahlreicher NGOs und Konsument:innenschutzverbände von Beginn an vor zu unscharfen Regelungen ua im Bereich der biometrischen Überwachung. Die vorliegende Diplomarbeit soll am Beispiel biometrischer Überwachungstechnologien – mit Fokus auf biometrische Fernidentifizierungssysteme – analysieren, ob durch die KI-VO Tür und Tor für eine Massenüberwachung geöffnet werden oder das Grundrecht auf Privatsphäre gem Art 7 GRC und Art 9 EMRK ausreichend geschützt wird.eingereicht von Nina AndreeDiplomarbeit Johannes Kepler Universität Linz 202
Journal für Gastroenterologische und Hepatologische Erkrankungen / Chirurgische Optionen bei Krankheiten des Pankreas
No full textZusammenfassung Aufgrund der Komplexität der Eingriffe und der hohen Komplikationsrate ist die Pankreaschirurgie eines der anspruchsvollsten Gebiete der Viszeralchirurgie. Dieser Artikel bietet einen umfassenden Überblick über aktuelle chirurgische Techniken, einschließlich der Pankreatikoduodenektomie und der linksseitigen und totalen Pankreatektomie, mit besonderem Fokus auf deren Indikationen, Vorteile und Risiken. Der Einsatz minimal-invasiver Verfahren, wie der laparoskopischen und robotergestützten Chirurgie, verändert das Fachgebiet nachhaltig. Diese Techniken bieten unter Wahrung der onkologischen Sicherheit potenzielle Vorteile wie kürzere Krankenhausaufenthalte und schnellere Erholung. Dennoch bleiben postoperative Komplikationen, wie Pankreasfisteln, Blutungen und verzögerte Magenentleerung, weiterhin große Herausforderungen. Ein interdisziplinärer Ansatz unter Einbeziehung der Chirurgie, Onkologie, Radiologie und Intensivmedizin spielt eine entscheidende Rolle bei der Verbesserung der Behandlungsergebnisse. Fortschritte in der chirurgischen Planung und intraoperativen Navigation sowie molekulare Profilierung und zielgerichtete Therapien eröffnen vielversprechende Möglichkeiten für maßgeschneiderte Behandlungsstrategien. Darüber hinaus tragen optimierte Recovery-Protokolle zur Verbesserung der postoperativen Versorgung bei, reduzieren die Morbidität und steigern die Lebensqualität der Patienten. Mit fortschreitender Forschung werden weitere Innovationen in der Pankreaschirurgie erwartet, die die chirurgischen Techniken weiter verfeinern, Komplikationen minimieren und die Langzeitüberlebensraten verbessern werden.Abstract Pancreatic surgery remains one of the most challenging fields in gastrointestinal surgery due to the complexity of the procedures and the high risk of postoperative complications. This article provides a comprehensive overview of current surgical techniques, including pancreaticoduodenectomy, left-sided and total pancreatectomy, with a focus on their indications, benefits, and risks. The adoption of minimally invasive techniques, including laparoscopic and robotic-assisted approaches, is transforming the field, offering potential benefits such as shorter hospital stays and faster recovery while maintaining oncological safety. However, postoperative complications, including pancreatic fistula, hemorrhage, and delayed gastric emptying, remain significant challenges. The role of a multidisciplinary approach, involving surgeons, oncologists, radiologists, and intensivists, plays a crucial role in improving patient outcomes. Advances in surgical planning and intraoperative navigation, along with molecular profiling and targeted therapies are promising avenues for personalized treatment strategies. Additionally, enhanced recovery protocols are improving postoperative care, reducing morbidity, and enhancing patients’ quality of life. As research continues, innovations in pancreatic surgery are expected to refine surgical techniques, minimize complications, and improve long-term survival rates
Next Research / Patient-reported outcome of bilateral and contralateral risk-reducing mastectomy: A cross- sectional study
No full textÖsterreichische Zeitschrift für Soziologie / Haben sich die Bildungsungleichheiten im weiterführenden Schulsystem in Österreich seit Ende der 1990er-Jahre geändert?
No full textZusammenfassung Seit Ende der 1990er-Jahre hat sich die soziale und ethnische Zusammensetzung der Schüler:innen in Österreich deutlich geändert. Zusätzlich fanden in diesem Zeitraum mehrere ökonomische, politische und soziale Krisen statt und umfangreiche Bildungsreformen wurden beschlossen. Auf das Ausmaß der Bildungsungleichheiten scheinen diese Veränderungen und Ereignisse entsprechend der Berichterstattung zur PISA-Studie oder zu anderen Bildungsstudien keinen Einfluss gehabt zu haben. Das ist bei näherer Betrachtung überraschend und der vorliegende Beitrag geht der Frage nach, ob dies tatsächlich der Fall ist oder ob Änderungen zumindest in Teilbereichen beobachtbar sind. Ausgangspunkt ist eine Studie aus dem Jahr 2003, die mit aktuellen Daten aus dem EU-SILC für die Jahre 2018 bis 2022 repliziert wird. Untersucht wird der Besuch einer maturaführenden Schule in der Gruppe der 16- bis 19-Jährigen. Die Ergebnisse zeigen, dass der Einfluss der Bildung der Eltern deutlich gestiegen ist. Bei einer detaillierteren Betrachtung ergeben sich zudem Hinweise auf Covid-19-Effekte bzgl. Geschlecht und familienstruktureller Variablen.Abstract Since the end of the 1990s, the social and ethnic composition of pupils in Austria has changed significantly, there have been and still are several crises and educational reforms have taken place. According to reports on PISA or other educational studies, these changes and events have not influenced educational inequalities. On closer inspection, this is a surprising finding. Therefore, this paper examines the question of whether this is actually the case or whether changes—at least in some dimensions of inequalities—can be observed. The starting point is a study from 2003, which is replicated with current data from the EU-SILC for the years 2018 to 2022. The study analyses the attendance of schools leading to a university entrance allowance in the group of 16 to 19-year-olds. The results show that the influence of parental education has increased significantly. In addition, a more detailed analysis reveals possible Covid 19 effects with regard to gender and family structure
Platinbeschichtete Ti-Anoden im Vergleich zu Ir-Anoden für die galvanische Abscheidung von Zink auf Stahl
No full textThe Linz site of the voestalpine Stahl GmbH is a big producer of zinc coated steel for the automobile industry. One well established production technique among others is the electrolytic deposition of zinc on steel sheets with Gravitel® cells and dimension stable anodes (DSA). The steel sheet gets passed through a Zn-electrolyte in the Gravitel® cell and is switched as cathode where the dissolved zinc gets deposited via reduction when current is applied. The anodic reaction occurs at the DSA, where the oxygen evolution reaction (OER) takes place through the oxidation of hydroxide ions (OH⁻) in the electrolyte.
Within this master’s thesis the focus lies on the anodic part. Many materials are suitable for the OER and one of the established types up to date is the IrO2 coated titanium electrode (Ir-anode). Their lifetime is defined by the IrO2 coating which is applied on Ti substrate. The degradation and failure of these anodes is resulting from the passivation of the Ti underneath the coating when the IrO2 layer becomes worn out.
This thesis investigates an alternative anodic type for the OER; the platinum coated Ti-anode. The catalytic character of platinum concerning OER has been studied very well and inferior compared to ceramic based coatings due to higher needed overvoltage.
The rationale for the use of platinum coated titanium can be possible longer lifetime given by a different production process of the electrode. Traditionally, the sol-gel technique is used to apply the coating on the titanium substrate. In this case the platinum is applied via high temperature electrolysis.
The study included SEM analyses, electrochemical simulations, and degradation tests to compare both electrode types. SEM imaging revealed a smooth and dense surface for the Pt-anode, while the Ir-anode showed a rougher, bulkier structure. Electroplating simulations demonstrated that neither electrolyte type nor temperature had significant influence on overvoltage behavior.
In the experiment of the degradation by OER, the Ir-anode exhibited a signal loss of 24.1 % compared to only 10.3 % for the Pt-anode. Furthermore, Pt coating showed a high robustness to abrasion. The Tafel slope analysis revealed that Ir-anodes show superior OER kinetics, especially in industrially relevant electrolytes, with overvoltage differences increasing up to 0.62 V.submitted by Florian NußbaumerAbweichender Titel laut Übersetzung der Verfasserin/des VerfassersMasterarbeit Johannes Kepler Universität Linz 202
Organisational scaling of food- tech startups: the role of entrepreneurial ecosystems
No full textThe food- tech sector represents a dynamic intersection of technological innovation, sustainability, and consumer culture- an area that continues to gain relevance both economically and societally. This thesis explores how entrepreneurial ecosystems enable the organizational scaling of food- tech startups, with a particular focus on the Austrian context. Combining a comprehensive literature review with thirteen qualitative expert interviews, the study investigates which ecosystem elements are most critical to support scaling and how their effectiveness is shaped by sector- specific and institutional characteristics.
Building on established entrepreneurial ecosystem models, the thesis introduces an adapted ecosystem- scaling framework that conceptualises scaling as a recursive alignment process between firm- level capabilities and the evolving resources of the ecosystem. Empirical findings confirm the relevance of core ecosystem elements- such as finance, regulation, market access, and relational networks- but reveal their highly contextualised nature in food- tech. In Austria, a pronounced funding gap, rigid regulatory frameworks, and the dominance of retail gatekeepers emerged as key bottlenecks. At the same time, relational intermediaries, founder motivation, and consumer education proved to be decisive soft enablers of growth.
The study makes theoretical contributions by embedding sectoral and temporal dynamics into ecosystem theory and offers practical recommendations to enhance Austria’s food- tech scale- up potential. These include bridging funding gaps, streamlining regulation, diversifying market channels, strengthening brokerage infrastructure, and institutionalising legitimacy- building measures. Overall, the thesis offers a nuanced understanding of how entrepreneurial ecosystems can act as dynamic enablers of startup scaling- and what it takes to make that potential tangible.Author Carolina Victoria BaumannMasterarbeit Johannes Kepler Universität Linz 202