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Validation of real-time aging simulation of poly(lactic acid) (PLA) using accelerated aging in accordance with ASTM F1980 [Dataset]
No full textTo advance the application of bio-based materials in medical technology, further research is required to assess their long-term performance. In common practice, accelerated aging tests based on ASTM F1980 are used in medical contexts to predict material behavior over time. This standard provides calculation guidelines to determine the equivalent storage duration under artificially accelerated aging conditions using a Q10-factor. This factor, typically assumed to be 2, represents the increase in reaction rate due to elevated temperatures.
In this study, a comparison was conducted between accelerated aged samples and their real-time equivalents using various PLA types. The results indicate that the standard assumption of Q10 = 2 can lead to an overestimation of degradation, resulting in a misrepresentation of real-time aging behavior. This discrepancy is substantiated by experimental data, including mechanical, thermal, and chemical analyses. A key factor contributing to this deviation appears to be the reliance on overly simplistic assumptions regarding degradation kinetics, which fail to account for autocatalytic reactions and the inherently multi-stage nature of the degradation process. In the present study, this observation was further corroborated through the determination of material-specific Q10-factors. These factors, found to range between 2.3 and 2.5, exhibited dynamic variations throughout the degradation process, highlighting the need for a refined approach to accelerated aging methodologies.2220NR089
Transkript des zweiten Projekttreffens 'Wie Bilder laufen lernten'
No full text<p>Der Datensatz stammt aus der Dissertation &bdquo;Das au&szlig;erunterrichtliche Lernangebot &sbquo;Kinder-Uni&lsquo; als Ressource f&uuml;r den Ausbau kindlicher Diskurskompetenz: Rekonstruktion explanativer diskursiver Praktiken in einem ausgew&auml;hlten Lehr-Lernarrangement f&uuml;r Sch&uuml;ler/innen der Primarstufe&ldquo;. Die gespr&auml;chsanalytisch orientierte Studie untersucht das Potenzial des au&szlig;erunterrichtlichen Lernangebots &sbquo;Kinder-Uni&lsquo; f&uuml;r die F&ouml;rderung diskursiver F&auml;higkeiten von Grundschulkindern, besonders im Kontext von Bildungsbenachteiligung bei Kindern mit Zuwanderungshintergrund. Analysiert werden Interaktionen zwischen Kindern und Studierenden, wobei rekonstruiert wird, wie beide Seiten die Relevanz kindlicher Erkl&auml;rungen herstellen und gespr&auml;chsstrukturelle Aufgaben gemeinsam bearbeiten. Die Ergebnisse zeigen, dass das Lehr-Lernarrangement Potenzial zur F&ouml;rderung von Erkl&auml;rkompetenz besitzt, insbesondere hinsichtlich der Dimensionen &bdquo;Kontextualisierung&ldquo; und &bdquo;Vertextung&ldquo;.</p>
<p>Im Lehr-Lernarrangement &bdquo;Wie Bilder laufen lernten&ldquo; erstellen Lehramtsstudierende gemeinsam mit mehrsprachig aufwachsenden Grundschulkindern einen Legom&auml;nnchen-Film. Beim zweiten Projekttreffen besch&auml;ftigen sich die Kinder zun&auml;chst damit, wie viele Einzelbilder n&ouml;tig sind, um eine Bewegung sichtbar zu machen. Danach entwickeln sie gemeinsam die Handlung des Films, besorgen geeignete Materialien und nehmen erste Probebilder auf.</p>
<p>Transkriptionskonventionen: GAT2 &ndash; Basistranskript<br />Ursprungsdatei: Audioaufnahme mit einem Audio-Recorder ZOOM H1n</p>
Exploiting the Full Potential of Power Electronics Converters by Optimizing Operating Parameters - Power Loss and Thermal Measurement Data
No full textThe trend towards an all-electric society leads to an increasing demand for highly efficient power converters. Especially power supplies for higher power applications are often realized by multi- (two-) stage converters. This underlying work contributes an integrative approach to model and optimize the power converter losses and thermal behavior of the different stages. For optimization, it is important to develop a loss model that is both adaptable and calculation efficient to minimize time for optimization. The presented loss model is based on physical equations and datasheet parameters to account for simple adaptability. At the same time, it relies on analytical equations wherever possible to reduce complexity. The work results in a deviation of loss estimation below 4 % for modeling the losses of a built-up prototype power supply. The transient thermal model achieves a deviation below 5.3 %. Model complexity is minimized enabling the execution on a 160 MHz microcontroller for digital control within 95 ms while performing converter control at the same time. The loss model is finally used to optimize control parameters to either decrease power losses at a given transfer power or to optimize output power while aligning with maximum component temperatures. An average power loss reduction of 17.1 % is achieved by operation point variant operating parameters referred to optimized constant parameters. In a second optimization approach a transient output power increase of 11.2 % during the first 30 minutes of operation is reached by actively controlling the loss distribution to exploit thermal impedances.
This repository contains the power loss and thermal measurement data used to validate the loss and thermal model. It is provided in .tar archives as .csv files.</p
Impact of a single-side 100Cr6 clad layer on the tensile and fatigue properties of S550MC steel [Dataset]
No full textThe production of newly developed hot-rolled layered metal composites (LMC) leads to the availability of sheet materials with specifically adjustable, graded properties being cost-effective and suitable for large-scale production. As many of the envisaged applications of these LMC, e.g., clutch disc carriers, suffer from cyclic loading during service life, a fundamental knowledge of the fatigue behavior is required in order to ensure safe and reliable application of the components. Therefore, the study described in https://doi.org/10.1111/ffe.14383 focuses on the fatigue behavior of a hot-rolled two-layer LMC consisting of a S550MC substrate layer and a 100Cr6 clad layer. In order to investigate the influence of the clad layer, two conditions are directly compared, i.e., the two-layer laminate cladded steel and the single-layer substrate condition.This dataset focuses on the fatigue and tensile behavior as well as the corresponding fracture surfaces, microstructure and hardness distribution of the two-layer cladded steel and the substrate.IMPORTANT: In case you use the data please cite our corresponding article https://doi.org/10.1111/ffe.14383Grant/Award Number: 46173478
Navigating the Remanufacturing Trilemma: Balancing Customer, Manufacturer, and Lawmaker Interests [Repository]
Full text linkThe associated paper explores the trilemma between different circular economy stakeholders (customer, manufacturer and legislator). The overview database (2019-2024) contains 84 relevant papers (out of 880), which were reduced to 27 through analysis. In addition, findings from expert interviews are used to uncover conflicts and synergies.
The provided Excel file contains the researched literature and documents the process and findings. The main content is found in "References". Each PDF contains an interview protocol, numbered according to the paper’s Table 3. Each protocol contains a description of the expert and a discussion summary.
The provided presentation was used as a guide to conduct the interviews.</p
Performance and meat quality of 58 Angler Saddleback pigs (supplemental data)
No full textThe two datasets consists of phenotypes of 58 Angler Saddleback pigs related to performance, carcass and meat quality traits. The pigs were fattened at an experimental farm of the University of Kiel between 2018 and 2020. The first dataset is related to the publication "Performance, carcass quality and meat quality of the endangered German Angler Saddleback pig" (DOI: 10.1371/journal.pone.0300361). The second dataset is related to the publication "Fatty acid composition and genome-wide association analysis for intramuscular fat and backfat of the Angler Saddleback pig".“European Innovation Partnership” (EIP Agri
Herausforderungen und Chancen
No full textDaten und Auswertung einer Befragung, die im Kontext der Veranstaltung "Wissenschaft trifft Wirtschaft: Digitaler Zwilling in Produktion und Logistik" am 08.10.2024 im Science Park Kassel stattgefunden hat. Im Rahmen der Veranstaltung wurde eine interaktive Publikumsbefragung mit Mentimeter durchgeführt. Die Daten, erfasst über das Webtool und exportiert als Excel-Tabelle, bilden die Grundlage für die Analyse. Ergänzend zur Befragung wurde eine umfassende Literaturrecherche durchgeführt, die aus 244 Treffern 47 relevante Quellen identifizierte. Aus diesen 47 Quellen wurden 8 Quellen zur detaillierten Untersuchung ausgewählt. Diese bilden die Grundlage zur Beantwortung der Forschungsfragen: "Welche Anwendungsfälle des Digitalen Zwillings gibt es?" und "Welche Herausforderungen bestehen bei der Implementierung und Nutzung Digitaler Zwillinge?
Supplementary data to the publication "Remote sensing-based long-term assessment of bioenergy policy impact on agricultural land cover change: A case study of biogas in the Weser-Ems region in Germany"
No full textThis data set is a supplementary material to the publication "Remote sensing-based long-term assessment of bioenergy policy impact on agricultural land cover change: A case study of biogas in the Weser-Ems region in Germany" (Beila et al., 2025). It contains the calculation of a simplified reference factor for estimating the amount of maize silage used as cattle feed in the Weser-Ems Region, including assumptions and references used for the calculation. In addition, the data set includes graphs illustrating the share of maize silage used for biogas production in different municipalities, and the change in the number of cattle between years 1999 to 2020 per municipality.SYMOBIO project (grant number 031B1129A)0
Livelihood Strategies and Hardship
No full textMy name is Bano Begum. I was born in Shimshal and am 68 years old. During the old times we have experienced a lot of pain. We used to carry soil in Wurgesht [baskets made of willow sticks] to the livestock sheds [soil was layered everyday under livestock to make natural fertilizer] than carried the fertilizers to the agriculture fields. Land tilling and crop thrashings were all done with bulls and cows. We made bread roti of barley and wheat separately for which we needed [each year] three bags of wheat flour and three bags of barley per family that lasted from October to next July. In the past we were very poor and due to the hard work, our legs are not working now anymore. We also brought fire wood from the mountains [for cooking and heating] whereas now we have [planted] forests here and no one is going anywhere [to fetch wood]. Due to the blessing of Allah, times are good now.
Indeed, in the old days we have seen a lot of pain. Our fathers, husbands, and brothers have worked very hard to build the road [from Shimshal to Passu]. That is why our children now live a comfortable life and are traveling on this road comfortably.
Like fertilizer, we [Women] also fetched and carried water from long distance without a trolley or other help. We [women] had to take good care of our cattle so they could be used properly in agriculture work during the [agriculture] season.
Nowadays, nobody does such work anymore, it is an exciting time of ease. Nobody can imagine how painful the old times were. However, we did all work together: when someone went to cut grass, we all went along, if someone had to clean wheat, we all helped by cleaning it together. Now the Imam-e-Zaman has changed everything. Instead of being painful, life is so peaceful and there is a lot of emphasis on education for everybody.2.1.7.
Ritual Raacho Dance to Prevent Harm from the Village
No full textI am Muhammad Shafi from Jalalabad. It has been 55 years since I came here to Barmas, and I have been living here ever since.
In the old days, we had a tradition called raacho, in which we would play the drum for a man dance. We performed this ritual to prevent any harm from coming to the area and to ward off calamities. The day before, the boys would go and bring juniper and place it on a large rock. Then everyone would bring a mixture of different fruits ushaar from their homes and gather it in one place. One person would play the drum, and all others would dance together. After finishing this gathering, people would distribute the ushaar among the participants, and everyone would eat it. The next day, a spiritual healer danyal would come from the lower village, dancing all the way to the raacho rock and people would bring a sheep to be sacrificed. They would dance and sing, and everyone would enjoy. After that, they would place a target at a distance and shoot at it. Whoever hit the target would receive two portions of meat, and everyone else would get one portion each. One time, one of our relatives hit the target but refused to take the two portions. After completing this ritual, everyone would return to their homes.2.5.9.