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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
141

How to increase the understanding of differentials by using the Casio-calculator model 9860 G I/II to solve differential equations

Bjørneng, Bjørn 12 April 2012 (has links) (PDF)
The major aims of this paper are to present how we can improve the students understanding and involvement in mathematics by using a programming/graphic calculator. I will use differentials as examples such as differentiation ,integrals and differential equations, creating lines of slopes for differential equation of the type y’= f(x,y) . Find the solution of some differential equations by using regression and create the graph connected to the differential equation. As we have different approaches to solving a problem, it is a hope the students interest in mathematics will improve. The tools used will be programming, graphic commands as plot, f-line, etc. One goal is also to show how we can create small programs solving problems in mathematics. For many students this will be a stepping stone for further work with programming. The programs used can be copied using the program FA 124 that can be downloaded from Casios homepages. On request I can send you the programs.
142

Framing Education : Doing Comics Literacy in the Classroom

Wallner, Lars January 2017 (has links)
Interest in comics as Swedish school material has risen in the last few years and the publication of comics for children and adolescents has also increased. Meanwhile, although research around new literacies has taken an interest in combinations of image and text, there is still little research on comics as a literacy material, especially as part of school practices. With comics’ rise in popularity, and their quality as examples of new literacies, this points to the relevance of exploring how meaning making with comics is done in schools. The purpose of this study is to contribute knowledge on how locally situated literacy practices are done, practices in which pupils and teachers make meaning with comics. The study combines literacy, comics and discursive psychology to investigate aspects of literacy not as individual, inner workings, but as part of participants’ social constructions, in line with New Literacy Studies. With this perspective, it is possible to investigate literary concepts such as narrative, and participants’ construction of story elements, through the way in which these aspects are utilized by participants to construct social action – what participants do with their utterances. To study this, video recordings have been made in one primary and one secondary school, in two different Swedish cities. The results of the study show constructions of a comics literacy, where participants engage with both visual and textual aspects of the material and negotiate focalization of narrative perspective and construction of narrative structure as well as narrative devices such as speech and thought bubbles. Furthermore, meaning making of comics literacy also includes the construction of discourses around comics as a specific type of story telling, either for material or literary reasons. The thesis discusses how participants construct classroom literature, and provides insight into how interaction around comics enables participants to construct and negotiate discourses around what comics literacy is and what it enables, as well as how to talk about, create, and read comics. / Intresset för serier som svenskt skolmaterial har stigit de senaste åren och publiceringen av serier för barn och ungdomar har också ökat. Även om forskning om new literacies har intresserat sig för kombinationer av bild och text så finns det fortfarande lite forskning på serier som literacymaterial, speciellt som en del av skolpraktik. Med det stigande intresset för serier och deras kvaliteter som exempel på new literacies, så pekar detta mot att det finns en relevans i att utforska hur meningsskapande med serier görs i skolan. Syftet med denna studie är att bidra med kunskap om hur lokalt situerad literacypraktik görs där elever och lärare skapar mening med serier. Studien kombinerar forskning om literacy, serier och diskursiv psykologi för att, i linje med New Literacy Studies, undersöka aspekter av literacy som en del av deltagarnas sociala konstruktioner – inte som ett individuellt, mentalt fenomen. Med detta perspektiv är det möjligt att undersöka litterära koncept som narrativ och deltagares konstruktion av berättelseinslag, genom det sätt på vilka dessa aspekter används av deltagare för att interagera – vad deltagare gör när de säger något. För att studera detta har videoobservationer använts i en lågstadieskola och en högstadieskola i två olika svenska städer. Resultaten från studien demonstrerar konstruktioner av serie-literacy där deltagarna engagerar sig i både text och bild i materialet, diskuterar berättandeperspektiv och konstruktioner av narrativ struktur, såväl som berättarverktyg, t.ex. prat- och tankebubblor. Därutöver inkluderar serie-literacy också deltagarnas skapande av seriediskurser där serier görs till en specifik typ av berättande, antingen på materiell eller litterär basis. Avhandlingen diskuterar hur deltagare konstruerar klassrumslitteratur, och studien erbjuder en insikt i hur interaktion runt serier möjliggör för deltagare att konstruera och förhandla diskurser om vad serieliteracy är och vad det erbjuder för möjligheter, såväl som hur deltagare kan prata om, skapa och läsa serier.
143

How to increase the understanding of differentials by using the Casio-calculator model 9860 G I/II to solve differential equations

Bjørneng, Bjørn 12 April 2012 (has links)
The major aims of this paper are to present how we can improve the students understanding and involvement in mathematics by using a programming/graphic calculator. I will use differentials as examples such as differentiation ,integrals and differential equations, creating lines of slopes for differential equation of the type y’= f(x,y) . Find the solution of some differential equations by using regression and create the graph connected to the differential equation. As we have different approaches to solving a problem, it is a hope the students interest in mathematics will improve. The tools used will be programming, graphic commands as plot, f-line, etc. One goal is also to show how we can create small programs solving problems in mathematics. For many students this will be a stepping stone for further work with programming. The programs used can be copied using the program FA 124 that can be downloaded from Casios homepages. On request I can send you the programs.
144

Quality Assuring of Stator Winding Production : Using electrical tests to quality assure the process steps of a series stator winding production

Sayed Hamad, Tarek January 2021 (has links)
The demands for sustainable transportation have made battery electric vehicles an increasingly popular subject in the world of both businesses and engineering. This thesis has been made in collaboration with Scania, which is currently investigating the possibility of manufacturing stators and rotors in-house in a series production line. For Scania, the topic of quality assurance is of great importance as Scania wants to ensure their trucks and buses fulfil the quality requirements of both customers and society. The goal of the thesis is to provide Scania with a set of guidelines for what quality assurance steps to perform in a series stator winding production, and where in the production they should be placed. The investigated stator winding type is a continuous hairpin winding, and the investigated quality assurance steps are solely electrical tests used to ensure the safety, functionality, and quality of the stator windings. A process-failure modes and effects analysis were conducted to identify the risks associated with each production step. The results indicates where the quality assurance steps should be taken. Further analysis, based on the provided background of electrical tests, also provides an answer to what electrical tests to perform as quality assurance steps. The result of the thesis is a concept, presented in a flow chart diagram, which indicates what electrical tests to perform and where the tests should be performed in the stator winding production chain. / De krav som sätts på hållbar transport har gjort batteridrivna elektriska fordon ett alltmer populärt ämne i världens företag och ingenjörskonst. Denna avhandling har gjort i samarbete med Scania, som i nuläget utreder möjligheterna för att tillverka statorer och rotorer in- house i en serie produktionslinje. För Scania är ämnet kvalitetssäkring (QA) ett viktigt ämne, för att Scania vill säkerställa att deras lastbilar och bussar lever upp till de kvalitetskrav som både kunder och samhället ger. Avhandlingens mål är därför att förse Scania med en uppsättning av riktlinjer för vilka QA steg som ska utföras i en serie statorlindningsproduktion, och var i produktionen de ska placeras. Den statorlindningstypen i fokus är en kontinuerlig hårnålslindning, och att de kvalitetssäkringar som undersöks är enbart elektriska test som säkrar säkerhet, funktionalitet samt kvalitén av statorlindningarna. En P-FMEA har utförts som en risk och felläges analys i syfte att identifiera de risker som är associerat med varje produktionssteg. Resultatet pekar på var QA steg ska utföras någonstans. Fortsatt analys, baserat på den givna bakgrunden av elektriska test, ger även ett svar på vilka elektriska test som ska utföras som QA steg. Avhandlingens resultat är ett koncept, presenterat i ett flödesdiagram, som visar vilka elektriska test som ska utföras samt var dessa tests ska utföras i statorlindningsproduktionen.
145

On Reliability of SiC Power Devices in Power Electronics

Sadik, Diane-Perle January 2017 (has links)
Silicon Carbide (SiC) is a wide-bandgap (WBG) semiconductor materialwhich has several advantages such as higher maximum electric field, lowerON-state resistance, higher switching speeds, and higher maximum allowablejunction operation temperature compared to Silicon (Si). In the 1.2 kV - 1.7kV voltage range, power devices in SiC are foreseen to replace Si Insulatedgatebipolar transistors (IGBTs) for applications targeting high efficiency,high operation temperatures and/or volume reductions. In particular, theSiC Metal-oxide semiconductor field-effect transistor (MOSFET) – which isvoltage controlled and normally-OFF – is the device of choice due to the easeof its implementation in designs using Si IGBTs.In this work the reliability of SiC devices, in particular that of the SiCMOSFET, has been investigated. First, the possibility of paralleling two discreteSiC MOSFETs is investigated and validated through static and dynamictests. Parallel-connection was found to be unproblematic. Secondly, drifts ofthe threshold voltage and forward voltage of the body diode of the SiC MOSFETare investigated through long-term tests. Also these reliability aspectswere found to be unproblematic. Thirdly, the impact of the package on thechip reliability is discussed through a modeling of the parasitic inductancesof a standard module and the impact of those inductances on the gate oxide.The model shows imbalances in stray inductances and parasitic elementsthat are problematic for high-speed switching. A long-term test on the impactof humidity on junction terminations of SiC MOSFETs dies and SiCSchottky dies encapsulated in the same standard package reveals early degradationfor some modules situated outdoors. Then, the short-circuit behaviorof three different types (bipolar junction transistor, junction field-effect transistor,and MOSFET) of 1.2 kV SiC switching devices is investigated throughexperiments and simulations. The necessity to turn OFF the device quicklyduring a fault is supported with a detailed electro-thermal analysis for eachdevice. Design guidelines towards a rugged and fast short-circuit protectionare derived. For each device, a short-circuit protection driver was designed,built and validated experimentally. The possibility of designing diode-lessconverters with SiC MOSFETs is investigated with focus on surge currenttests through the body diode. The discovered fault mechanism is the triggeringof the npn parasitic bipolar transistor. Finally, a life-cycle cost analysis(LCCA) has been performed revealing that the introduction of SiC MOSFETsin already existing IGBT designs is economically interesting. In fact,the initial investment is saved later on due to a higher efficiency. Moreover,the reliability is improved, which is beneficial from a risk-management pointof-view. The total investment over 20 years is approximately 30 % lower fora converter with SiC MOSFETs although the initial converter cost is 30 %higher. / Kiselkarbid (SiC) är ett bredbandgapsmaterial (WBG) som har flera fördelar,såsom högre maximal elektrisk fältstyrka, lägre ON-state resitans, högreswitch-hastighet och högre maximalt tillåten arbetstemperatur jämförtmed kisel (Si). I spänningsområdet 1,2-1,7 kV förutses att effekthalvledarkomponenteri SiC kommer att ersätta Si Insulated-gate bipolar transistorer(IGBT:er) i tillämpningar där hög verkningsgrad, hög arbetstemperatur ellervolymreduktioner eftersträvas. Förstahandsvalet är en SiC Metal-oxidesemiconductor field-effect transistor (MOSFET) som är spänningsstyrd ochnormally-OFF, egenskaper som möjliggör enkel implementering i konstruktionersom använder Si IGBTer.I detta arbete undersöks tillförlitligheten av SiC komponenter, specielltSiC MOSFET:en. Först undersöks möjligheten att parallellkoppla tvådiskretaSiC MOSFET:ar genom statiska och dynamiska prov. Parallellkopplingbefanns vara oproblematisk. Sedan undersöks drift av tröskelspänning ochbody-diodens framspänning genom långtidsprov. Ocksådessa tillförlitlighetsaspekterbefanns vara oproblematiska. Därefter undersöks kapslingens inverkanpåchip:et genom modellering av parasitiska induktanser hos en standardmoduloch inverkan av dessa induktanser pågate-oxiden. Modellen påvisaren obalans mellan de parasitiska induktanserna, något som kan varaproblematiskt för snabb switchning. Ett långtidstest av inverkan från fuktpåkant-termineringar för SiC-MOSFET:ar och SiC-Schottky-dioder i sammastandardmodul avslöjar tidiga tecken pådegradering för vissa moduler somvarit utomhus. Därefter undersöks kortslutningsbeteende för tre typer (bipolärtransistor,junction-field-effect transistor och MOSFET) av 1.2 kV effekthalvledarswitchargenom experiment och simuleringar. Behovet att stänga avkomponenten snabbt stöds av detaljerade elektrotermiska simuleringar för allatre komponenter. Konstruktionsriktlinjer för ett robust och snabbt kortslutningsskyddtas fram. För var och en av komponenterna byggs en drivkrets medkortslutningsskydd som valideras experimentellt. Möjligheten att konstrueradiodlösa omvandlare med SiC MOSFET:ar undersöks med fokus påstötströmmargenom body-dioden. Den upptäckta felmekanismen är ett oönskat tillslagav den parasitiska npn-transistorn. Slutligen utförs en livscykelanalys(LCCA) som avslöjar att introduktionen av SiC MOSFET:ar i existerandeIGBT-konstruktioner är ekonomiskt intressant. Den initiala investeringensparas in senare pågrund av en högre verkningsgrad. Dessutom förbättrastillförlitligheten, vilket är fördelaktigt ur ett riskhanteringsperspektiv. Dentotala investeringen över 20 år är ungefär 30 % lägre för en omvandlare medSiC MOSFET:ar även om initialkostnaden är 30 % högre. / <p>QC 20170524</p>
146

Life after Harry / Eine Gattungsdiskussion zeitgenössischer Kinder- und Jugendliteratur in der Post-Potter-Ära / Life After Harry / Contemporary Children’s Literature and Young Adult Fiction in the Post-Potter Era – a Discussion of Genre Aspects

Fitz, Victoria 03 March 2015 (has links)
No description available.
147

Individual Approaches in Rich Learning Situations Material-based Learning with Pinboards

Katzenbach, Michael 02 May 2012 (has links) (PDF)
Active Approaches provide chances for individual, comprehension-oriented learning and can facilitate the acquirement of general mathematical competencies. Using the example of pinboards, which were developed for different areas of the secondary level, workshop participants experience, discuss and further develop learning tasks, which can be used for free activities, for material based concept formation, for coping with heterogeneity, for intelligent exercises, as tool for the presentation of students’ work and as basis for games. The material also allows some continuous movements and can thus prepare an insightful usage of dynamic geometry programs. Central Part of the workshop is a work-sharing group work with learning tasks for grades 5 to 8. The workshop will close with a discussion of general aspects of material-based learning.
148

Individual Approaches in Rich Learning Situations Material-based Learning with Pinboards

Katzenbach, Michael 02 May 2012 (has links)
Active Approaches provide chances for individual, comprehension-oriented learning and can facilitate the acquirement of general mathematical competencies. Using the example of pinboards, which were developed for different areas of the secondary level, workshop participants experience, discuss and further develop learning tasks, which can be used for free activities, for material based concept formation, for coping with heterogeneity, for intelligent exercises, as tool for the presentation of students’ work and as basis for games. The material also allows some continuous movements and can thus prepare an insightful usage of dynamic geometry programs. Central Part of the workshop is a work-sharing group work with learning tasks for grades 5 to 8. The workshop will close with a discussion of general aspects of material-based learning.
149

Le participe dans les grammaires des langues romanes (XVe-XVIIIe siècles). Histoire comparée d'une classe grammaticale / The participle in the Romance Languages' grammars (15th-18th centuries). A compared history of a grammar category / El participio en las gramáticas de las lenguas románicas (siglos XV-XVIII). Historia comparada de una clase gramatical

Diaz Villalba, Alejandro 13 September 2017 (has links)
L’étude présente l’histoire de la classe du participe à travers un corpus de grammaires del’espagnol, du français, de l’italien et du portugais parues entre le XVe et le XVIIIe siècle.La démarche comparative s’appuie sur le principe méthodologique de la mise en série d’une centaine d’ouvrages regroupés et confrontés selon des paramètres variables : la chronologie, le thème ou la tradition grammaticale de la langue-objet.La première partie aborde la question de la catégorisation en linguistique et s’interroge sur la nature des formes non finies du verbe, tout particulièrement du participe et de son emploi dans les formes verbales analytiques. La deuxième partie traite de l’histoire du participe sous un angle général. Ainsi, après avoir donné un aperçu des aspects problématiques qui intéressent les grammairiens grecs et latins, l’analyse se centre sur le traitement de la classe dans les grammaires des langues romanes. La troisième partie s’attache à étudier les approches et les concepts dont se servent les grammairiens de la Renaissance pour traiter les temps composés ainsi que la façon dont ils décrivent et (re)catégorisent les formes participiales de ces temps verbaux. / The study investigates the history of the word-class of participle through a close study of a corpus of French, Spanish, Portuguese and Italian grammars which were published between the 15th and 18th centuries. The comparative approach is based on the methodological principle of “series of texts”, by grouping and collating a hundred works according to several variable parameters: the chronology, the theme or the grammatical tradition of the language in question.The first part of the study deals with the linguistic categorization and questions the nature of the non-finite verbal forms, especially the participle and its use in an analytical verbal form. The second part deals with the history of the participle from a more general point of view. Thus, after an overview of the problematic aspects of Greek and Latin grammarians, the analysis focuses on the treatment of the word-class in the grammars of the Romance languages. The third part focuses on the approaches and concepts used by the Renaissance grammarians to deal with compound tenses and on how they described and (re)-categorized the participle forms of these verbal tenses. / El estudio presenta la historia de la clase del participio a través de un corpus de gramáticas de español, francés, italiano y portugués publicadas entre los siglos XV y XVIII. El enfoque comparativo se basa en el principio metodológico de la constitución de series textuales, que nos permite agrupar y cotejar un centenar de textos en función de parámetros variables: la cronología, el tema o la tradición gramatical de la lengua objeto.La primera parte aborda el asunto de la categorización en lingüística e indaga la naturaleza de las formas no finitas del verbo, especialmente la del participio y su utilización en las formas analíticas del verbo. La segunda parte propone una aproximacióna la historia del participio desde una perspectiva más general. Así pues, tras una cala en los aspectos problemáticos relacionados con el participio tratados por los gramáticos griegos y latinos, el análisis se centra en el tratamiento de la clase en las gramáticas de las lenguas romances. La tercera parte investiga sobre los enfoques y los conceptos que emplean los gramáticos del Renacimiento para tratar los tiempos compuestos, y sobre el modo en que describen y (re)categorizan las formas participiales de esos tiempos verbales.

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