Determination of Electromagnetic Material Properties of Ferromagnetic Stainless Steel Used in Domestic Induction Heating Cookware

Design-oriented modeling approaches, such as finite element analyses (FEA), rely on accurate material data for the modeled hardware. In the case of cookware used in domestic induction heating (IH) systems, manufacturers rarely provide the necessary data. Therefore, this contribution presents results for the electromagnetic material properties of ferromagnetic stainless steel, typically used in cookware for domestic IH. The magnetic material properties are modeled using Jiles-Atherton hysteresis model. With the used measurement method, less effort in preparation of suited material specimen is needed compared to conventional measurement methods. The presented results for the magnetic material properties are validated using Epstein frame measurements. It is shown that the hysteresis curves are similar to each other for both measurement methods. Regarding the specific electrical resistance, the results are validated using a microhmmeter. The values determined for the specific resistance show good accordance for the different measurement methods

Psychoonkologischer Distress bei Patienten in strahlentherapeutischer Behandlung

In den bisher vorliegenden klinischen Studien lag der Fokus für die Erfassung von Distress bei Krebspatienten im Wesentlichen auf einer spezifischen Tumorentität wie Brustkrebs, Hautkrebs etc., womit die Perspektive auf ein eng umschriebenes Spektrum in der Psychoonkologie beschränkt war. Ziel dieser Studie ist die Erfassung von Angst, Depressivität und Distress bei Patienten in strahlentherapeutischer Behandlung. Das Augenmerk liegt dabei auf der Erfassung aller behandelten Tumorentitäten, was den charakteristischen Aspekt der Arbeit darstellt. Für diese Pilotstudie wurden 108 Patienten während ihrer Behandlung in der Universitätsklinik für Radioonkologie in Tübingen über verschiedene Screening-Instrumente mittels Fragebögen (DT-Fragebogen, HADS, PHQ-9, SF-12) hinsichtlich des vorhandenen psychoonkologischen Distress untersucht. Neben Häufigkeitsanalysen und Korrelationen einzelner Variablen wurden speziell die Prädiktoren für Angst, Depressivität und Distress während Strahlentherapie berechnet. Die Angst korreliert dabei signifikant mit einem auffälligen generellen Distressempfinden. Die in dieser Arbeit betrachteten Patienten zeigten während Strahlentherapie zudem signifikant höhere psychische und körperliche Einschränkungen als die Normstichprobe bei Krebspatienten. Es ist erkennbar, dass neben der allgemein höheren psychischen und körperlichen Einschränkung bei Patienten das Angstempfinden und der Distress während strahlentherapeutischer Behandlung als höher beschrieben werden als in vergleichbaren Studien bei Krebspatienten ohne Strahlenbehandlung. Dies stellt den Behandlungspfeiler Strahlentherapie als möglicherweise belastender und einschränkender als andere Therapieoptionen für Krebspatienten dar. Ein wesentliches Ergebnis dieser Arbeit betrifft die aktuelle Behandlungsintention. Zwar sind Patienten bei palliativer Behandlungsabsicht stärker von Angst belastet als jene in kurativer Behandlung, jedoch zeigen Patienten mit zum Zeitpunkt der Datenerhebung noch unklarer Behandlungsabsicht oder einer noch unklaren Tumorausdehnung noch deutlich höhere Belastungen. Dies hat auch für die klinische Praxis besondere Relevanz. Gerade in der Phase der Krebsdiagnose und des Stagings sollte den Patienten bei noch unklarer krankheitsbedingter Therapieindikation besondere psychoonkologische Unterstützung angeboten werden. Patienten der Tumorkategorien Verdauungstrakt und Mamma sind, im Gegensatz zu Patienten der Kategorie Lunge, während der Strahlenbehandlung am geringsten körperlich eingeschränkt. Patienten mit Malignom an Lunge und Pleura zählen in dieser Studie zu den Risikopatienten, bei denen sowohl Angst, Depressivität als auch genereller Distress erhöht sind und die gesundheitsbezogene Lebensqualität deutlich vermindert ist. Bei einer aktuell länger andauernden Behandlung ist der Distress geringer, wohingegen eine länger zurückliegende Erstdiagnose der Erkrankung bei Patienten zu höherem aktuellem Distress führt. Das Regressionsmodell aus Angst, körperlicher Einschränkung und Zeitdifferenz seit Erstdiagnose der Tumorerkrankung klärt in diesem Zusammenhang knapp ein Drittel des gesamten Distress der Patienten auf und lassen somit ein grundlegendes psychoonkologisches Risikoprofil während strahlentherapeutischer Behandlung entstehen. Hinsichtlich der klinischen Relevanz sollte der Fokus daher auf Risikopatienten mit hohen Angstwerten im Screening, einer körperlichen Einschränkung, einer länger zurückliegenden Erstdiagnose der Erkrankung, insbesondere auch bei Lungenerkrankungen, liegen. Die weiteren Tumorentitäten dürfen dabei jedoch nicht außer Acht gelassen werden, da auch hier durchweg ein erhöhtes Distressempfinden vorliegt. Die psychoonkologische Diagnostik von Patienten im strahlentherapeutischen Bereich sollte unter Beachtung des beschriebenen psychoonkologischen Risikoprofils etabliert werden sowie wiederholt erfolgen, um Behandlungspfade zugunsten jedes einzelnen Patienten zielführend steuern zu können

Determination and emulation of motor-like flux conditions for loss characterization by means of a single tooth geometry

High quantities and a demand on low costs in automotive drives result in new production methods of electrical machines. Besides, the electric drive train efficiency is improved to offer long ranges. Referring to this relationship the loss models of electrical machines are improved more and more. Focusing on iron losses, remarkable influences on the loss characteristics are attributed to the manufacturing processes. In this publication, a new approach of measuring the losses of a single stator tooth of an electrical machine considering motor-like flux conditions is introduced. Derivation of motor-like flux conditions is described, transfer to the test bench is defined and measurements are shown - concluding with a comparison of simulation and measurement as well as the identified tooth losses of the investigated machine. This gives the possibility to improve iron loss models in case of additional losses due to manufacturing influences

Effects of Semantic and Segmental Similarity on the Production and Learning of Spoken and Written Words

This dissertation investigates mechanisms of word production and learning, focusing on how semantic and segmental similarity affect the production and learning of words. Incremental learning models of spoken word production propose that learning occurs each time a familiar word is produced. In recent work, I argued that this type of model applies across stages and modalities of word production. Here, I extend the model to the learning of new words, incorporating insights from the literature regarding learning difficulty to make predictions about training effects and long-term learning outcomes. The extended incremental learning model (e-ILM) framework I propose makes testable predictions about the effects of training new words in semantic or segmentally related blocks vs. unrelated contexts. According to these predictions, semantic blocking is a desirable difficulty that causes interference during training but improves long-term learning by enhancing the distinctiveness of the learned representations. In contrast, segmental blocking is predicted to negatively affect both training and long-term learning because it reduces distinctiveness. Two studies tested these predictions. In the first, neurotypical adults learned names for novel items in semantic, segmental, and unrelated blocks in separate written and spoken experiments. Findings were consistent with the e-ILM predictions about training: although training in both types of related vs. unrelated blocks produced interference, semantic blocking increased distinctiveness while segmental blocking reduced distinctiveness. The predictions regarding long-term learning were less clearly supported because blocking did not consistently affect retention. In the second study, individuals with acquired dysgraphia relearned word spellings in semantic, segmental, and unrelated blocks. Group results did not consistently support the e-ILM predictions about training. However, there was evidence that both semantic and segmental blocking acted as desirable difficulties that improved long-term retention to the degree to which they increased training difficulty, suggesting that the general learning principle of desirable difficulty applies in this situation. Overall, the proposed e-ILM account accurately describes the underlying mechanisms that produce effects of blocking by semantic or segmental similarity during the (re)learning of words. The work raises potentially important questions regarding differences between new learning and relearning in neurotypical and brain damaged individuals that motivate further research

Loss Comparison of Small Delta- and Star-Connected Permanent Magnet Synchronous Machines

Delta-connected stator windings are often used in mass production of small Permanent Magnet Synchronous Machines (PMSMs). In comparison to star-connected stator windings, a delta-connected winding system offers advantages for manufacturing and lowers production costs. A main disadvantage of motors with such a winding system are additional losses caused by the Zero-Sequence Current Component (ZSCC). In this paper the ZSCC and its impact on the generated losses in a delta-connected PMSM used as a traction motor for a pedal electric cycle (Pedelec) is analysed. The calculated results are compared to those of a star-connected PMSM with the same design. We will show that the amplitude of the ZSCC depends on the operating point of the machine. As a result, the copper losses in the delta-connected machine are up to 5.8 % higher than the ones in the star-connected machine. On the other hand, the iron losses are 1 % smaller in the delta-connected machine. The efficiency of the delta-connected machine is still up to 4 % smaller

The effects of semantic and orthographic blocking on written word production

In investigating the efficacy of acquired dysgraphia treatments, relatively little attention has been directed to the relationships amongst treated items. Is it beneficial or detrimental to treat together items that belong to the same semantic category or share segments (phonemes or letters)? In spoken production, interference is observed when individuals produce items in the context of other semantically related vs. unrelated items—neurologically normal participants initiate naming more slowly and individuals with aphasia produce more errors (e.g. Damian et al., 2001; Schnur et al., 2006). On the other hand, facilitation is observed for the production of blocks of phonologically related vs. unrelated items— normal participants initiate naming more quickly (e.g. Damian, 2003), although there is some evidence of interference in individuals with aphasia (Hodgson et al., 2005). In the present study, we extend this research to examine the effects of semantic and orthographic blocking on written production in neurologically intact individuals (Experiments 1A and 1B) as well as one individual with acquired dysgraphia (Experiment 2). While the investigation does not involve treatment, the findings may have implications for word retrieval treatment

Rammeskift og repositionering: Hvordan påvirker COVID-19-lockdown læreres syn på skole-hjem-samarbejdet?

I artiklen sammenligner vi tre læreres syn på skole-hjem-samarbejdet før og under lockdown i forbindelse med indsatsen mod COVID-19. Lærerne er udvalgt på baggrund af et tidligere studie, da de positionerer sig på tre meget forskellige måder i forhold til skole-hjem-samarbejdet. På baggrund af interviews med disse lærere foretaget før og under lockdown, analyserer vi (1) forskelle og ligheder mellem de tre læreres syn på skole-hjem-samarbejdet inden lockdown, og undersøger dernæst (2) med udgangspunkt i Goffmans rammeteori og positioneringsteori, hvordan de respektive lærere håndterer det rammeskift, som omlægningen til hjemmeundervisning efter reglerne for nødundervisning medfører. Konklusionen er, at lærerne fastholder deres forskellige positioneringsstrategier i forhold til forældrene, hvilket giver dem særdeles forskellige udgangspunkter for at repositinere sig efter det rammeskift, som hjemmeundervisningen udgør.   AbstractIn this paper we analyze different strategies by which teachers position themselves in the teacher-parent cooperation, by comparing three teachers’ views on the cooperation before and after the COVID-19 Danish school lockdown. The teachers were selected based on a previous study where it was identified that they held distinct positions on, what was expected in the cooperation. Interviews were conducted with the teacher before and during the lockdow, and analyzed by applying Goffmann’s frame theory and positioning theory. The result is a demonstration of, how the individual teacher handles the “change in frames” that the school lockdown and teaching from home entails. The conclusion is that the teachers maintain their positioning-strategies in regard to the parents, which gives them very different basis for repositioning themselves after the change in frame