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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.
411

Horský hotel / Mountain hotel

Ducháček, Ondřej January 2014 (has links)
This master´s thesis deals with the design of the Mountain hotel with restaurant. The project is elaborated in the form of an implanting-level documentation. The object is situated at the land parcel No.115/5 in village cald Červená voda. The object is designed as tree-storey with the partially cellarage, the roof is propose as saddle roof.
412

Flyga högt och falla fritt : Feminism och postfeminism i Erica Jongs Rädd att flyga och Tone Schunnessons Tripprapporter

Grundberg, Lina January 2019 (has links)
This comparative essay discusses feminist and post-feminist concepts in the novels Fear of Flying by Erica Jong (1973) and Trip Reports by Tone Schunnesson (2016) from a generational perspective. The term feminism embraces both second-wave and third-wave feminism, while the term post-feminism represents the contradictions between and within the two. The analysis centers on the first-person narrators, Isadora Wing, in Fear of Flying, and the anonymous narrator, in Trip Reports. A phenomenological close-reading was employed to uncover generational differences, contradictions, and similarities in the texts, which were then analyzed through the lens of feminism and post-feminism. Examination of the texts was facilitated through the use of three categories: love, the body, and artistry. The primary theory utilized in the analysis is Toril Moi’s feminist theory developed out of Simon de Beauvoir’s reflections on “the body as situation,” where it is argued that a person’s lived experience, one’s whole subjectivity, is dependent upon and reflected through one’s body. The body forms the relationship to ourselves and our experience of the world, as well as how others view us. Thus, the female lived experience and each woman’s individual project is in this regard connected to having a female body. The results define differences in the narrators’ lived experiences and how the two women view themselves and others, in relation to societal norms and each narrator’s specific generation. Furthermore, the narrators’ are both ambivalent in their thoughts and actions. The identified similarities center around male dependency, various degrees – or lack of - female identification and traditional gender norms, independent of generation. The results of the analysis could offer a cultural and generational contribution to the current feminist literary discussion. / <p>Godkännande datum 2019-06-03</p>
413

Beitrag zum Elektronenstrahlfügen von TRIP-Matrix Kompositen

Halbauer, Lars 17 July 2020 (has links)
In der vorliegenden Arbeit wurde die Schweißbarkeit von hochlegierten TRIP-Matrix Verbundwerkstoffen (TMC) mit und ohne MgO teilstabilisiertem ZrO2 (Mg-PSZ) als Partikelverstärkungsphase mit Hilfe des Elektronenstrahl-Fügeverfahrens erstmals umfassend untersucht. An arteigenen, partikelfreien Fügeverbindungen wurde durch eine breite Parametervariation die Schweißnahtgeometrie, sowie die Auswirkungen des lokalen Temperaturgradienten auf die Mikrostrukturentwicklung untersucht. Die Schweißbarkeit der partikelfreien Stahlmatrix (3-9 Gew.-% Ni) ist sehr gut und wird durch die Neigung zum Humping beschränkt, die mit zunehmendem Nickelgehalt abnimmt. Unter quasistatischer und dynamischer Beanspruchung führt das Schweißen zu keiner signifikanten Beeinflussung der mechanischen Kennwerte. Lediglich bei zyklischer Beanspruchung kommt es zu einer Lebensdauerverringerung durch den Schweißprozess, die in der angegebenen Reihenfolge zunimmt: 16-7-3 --> 16-6-9 --> 16-7-6. Des Weiteren wurden zahlreiche Schweißungen an arteigenen, partikelverstärkten Fügeverbindungen durchgeführt, die trotz zahlreicher Optimierungen keine ausreichende Schweißbarkeit aufweisen. Grund dafür ist die Wechselwirkung zwischen Elektronenstrahl und Mg-PSZ-Partikeln, die zur explosionsartigen Verdampfung und der Bildung eines Hohlraums in der Schweißnahtmitte führen. Es wurden deshalb artfremde Schweißversuche durchgeführt, die in Abhängigkeit der Schweißgeschwindigkeit Rückschlüsse auf die zulässige Menge an Mg-PSZ in der Schweißzone zuließen. Durch EBSD und TEM-Untersuchungen konnten Grenzzustände für die Aufschmelzung des Verbundwerkstoffs identifiziert werden. Im letzten Teil der Arbeit wurde erstmal ein EB-Lötprozess mit Hilfe einer im Rahmen der Arbeit entwickelt und optimierten temperaturgesteuerten Leistungsregelung erfolgreich realisiert. Durch numerische Berechnungen konnte sowohl die laterale Energieverteilungsfunktion des Elektronenstrahls als auch die Spaltfüllung durch Wärmeausdehnung optimiert werden. Die entstandenen Lotverbindungen wurden mittels lichtmikroskopischer Aufnahmen und ESBD-Untersuchungen charakterisiert, zeigen eine hervorragende Anbindung durch ein chemisches Schmelzen des TMC-Grundwerkstoffs und besitzen Zugfestigkeiten von Rm ≤ 390 MPa.
414

Strain gradient based analysis of transformation induced plasticity in multiphase steels

Mazzoni, Louise 26 February 2010 (has links)
<p align='justify'>This thesis is devoted to the micromechanical study of the size-dependent strengthening in Transformation Induced Plasticity (TRIP) steels. Such grades of advanced high-strength steels are compelling for the automotive industry, due to their improved mechanical properties. Among others, they combine a good strength versus ductility balance. In this context, many research works have been carried out to study these grades of steels. In particular, from a numerical point of view, earlier studies within the framework of classical plasticity do not properly reproduce the strengthening levels characterizing TRIP steels and obtained experimentally.</p> <p><p align='justify'>In this study, the strain gradient plasticity theory presented by Fleck and Hutchinson (2001) is chosen to account for the strengthening effect resulting from the phase transformation. A two-dimensional embedded cell model of a simplified microstructure composed of small cylindrical metastable austenitic inclusions, partially undergoing the phase transformation, within a ferritic matrix is used.</p><p><p align='justify'>First, the single-parameter version of the strain gradient plasticity theory under small strain assumption is used for the simulations. The impact of the higher order boundary conditions is assessed. It is shown that, when the plastic flow is unconstrained at the elasto-plastic boundaries, the transformation strain has no significant impact on the overall strengthening. The strengthening is essentially coming from the composite effect with a marked inclusion size effect resulting from the appearance during deformation of new boundaries (at the interface between parent and product phases) constraining the plastic flow.</p><p><p align='justify'>Second, the multi-parameter version of the strain gradient plasticity theory, incorporating separately the rotational and extensional gradients in the formulation, is employed under small strain assumption. The effect of the plastic strain gradients resulting from the transformation strain is better captured. In particular, the results show a significant influence of the shear component of the transformation strain. An implicit confinement effect is revealed at the elasto-plastic boundaries which is partly responsible for the transformation strain effect. Size effects on the overall strengthening are also revealed, due to a combined size dependent effect of the transformation strain and of the evolving composite structure.</p><p align='justify'>Third, the extension of the strain gradient plasticity theory to a finite strain description is applied. A significant effect of the transformation strain is obtained with the multi-parameter version of the theory as well as an optimal austenite grain size improving the damage resistance of the martensite, in agreement with the typical grain size of the current TRIP-assisted steels (Jacques et al. 2007).</p> / Doctorat en Sciences de l'ingénieur / info:eu-repo/semantics/nonPublished
415

Kohlenstoffgebundene Funktionalbauteile für die Metallurgie mittels kalt-isostatischem Pressen

Ludwig, Susann 27 August 2020 (has links)
Im Rahmen der vorliegenden Arbeit wurden neuartige keramik- und stahlreiche Verbundwerkstoffe, auf Basis von MgO-teilstabilisiertem Zirkoniumdioxid und hochlegiertem austenitischem TRIP Stahl entwickelt. Die keramikreiche Verbundwerkstoffe mit bis zu 30 Vol.% metallischer Partikelverstärkung wurden über die Schlickergusstechnologie bzw. die Druckschlickergusstechnologie hergestellt und können als thermo-mechanisch beanspruchte Bauteile zum Einsatz kommen. Es wurden weiterhin metallreiche Verbundwerkstoffe mit bis zu 10 Vol.% keramischer Partikelverstärkung erstmalig über die Papiertechnologie hergestellt. Dadurch ergeben sich vielfältige Möglichkeiten metallreiche Leichtbaustrukturen mit verbesserten Energieabsorptionsvermögen zu erzeugen. Im Mittelpunkt der vorliegenden Arbeit stand die Entwicklung der keramikreichen Schlicker, die Formgebungstechnologien, die Entwicklung geeigneter Entbinderungs- und Sinterregime sowie die Charakterisierung der Verbundwerkstoffe hinsichtlich ihrer Mikrostruktur sowie der mechanischen bzw. der thermo-mechanischen Eigenschaften.
416

SAFE is the new COOL : A guide on how to do drugs responsibly

Bindar, Andreea Liliana January 2021 (has links)
In this essay, the research question: “How can I make teenagers use drugs more responsibly without using a scaremongering approach?” will be explored. The process will include theoretical research on the definition of drugs in relation to a strategy for reducing risks in the lives of adolescents, from a sustainable take. Another question that will be answered is why anti-drug campaigns fail, and my solution to this will be given. The result of this project will be in the form of an interactive online guide for teenagers. The aim of this project will be to provide high school students with a way to find important informa- tion they should know, before trying drugs. The case study is Romania. Here drugs are still a taboo subject and they are not explained nor talked about, in schools or families. Therefore, my guide provides explanations based on several people’s experiences and opinions about the most common drugs here.
417

Analyse de la cinétique de transformation et des instabilités de déformation dans des aciers TRIP "Moyen Manganèse" de 3ème génération / Analysis of transformation kinetics and strain instabilities in 3rd generation medium manganese TRIP Steels

Callahan, Michael 21 November 2017 (has links)
Cette thèse caractérise un acier Moyen Mn à 0.2C-5Mn-2.5Al qui montre un écrouissage très fort au cours de la déformation plastique dû à l’effet TRIP. Pendant TRIP, l’austénite résiduelle paramagnétique se transforme en martensite ferromagnétique sous déformation plastique, ce qui conduit à un fort écrouissage. Le taux de cet écrouissage dépend des paramètres de fabrication et surtout la température de recuit intercritique. Ces aciers ont aussi des fois le tendance de se déformer de façon hétérogène par des bandes de Lüders ou PLC.Dans cette thèse, une méthode de caractérisation de la cinétique de transformation de phase est développée sur la base des mesures de l’aimantation saturée de l’acier. La méthode magnétique est unique dans son implémentation in-situ sans aucun effet sur l’essai de traction. Une correction pour les effets de la contrainte appliquée sur l’aimantation est aussi introduite pour la première fois avec une base physique. Les résultats des mesures magnétiques ont été comparés contre des caractérisations des bandes de déformation pour montrer que la transformation de phase coïncide avec le passage des bandes de déformation. La sensibilité à la vitesse de déformation est analysée et une caractérisation de la présence et type de bande PLC est présentée en fonction de la cinétique de transformation de phase. / This thesis studies the mechanical behavior of a 0.2C-5Mn-2.5Al Medium Mn steel that exhibits a very high degree of work hardening due to transformation-induced plasticity (TRIP) during plastic deformation. During TRIP, paramagnetic retained austenite is transformed to ferromagnetic martensite with the application of plastic strain and generates a significant amount of work hardening. The rate of work hardening is seen to vary greatly depending on processing parameters—notably the intercritical annealing temperature. These steels also often deform heterogeneously through the propagation of Lüders or PLC strain bands.This research develops a method to characterize the kinetics of the TRIP effect through measurements of the samples magnetic properties. The method is novel in that it is performed in-situ with no effect on the tensile test and is able to correct for the effects of the applied stress on the magnetic properties. The results of these experiments were compared to characterizations of the strain bands to demonstrate that TRIP coincides with the passage of a Lüders or PLC band. The strain rate sensitivity of the steels is analyzed and the presence and type of PLC bands are characterized with respect to the transformation kinetics.
418

Liens entre activité physique quotidienne et utilisation de l’automobile comme moyen de transport : une étude transversale montréalaise

Parenteau, Nicolas 11 1900 (has links)
Contexte: La réduction de l'utilisation de l’automobile a déjà été identifiée comme étant une intervention populationnelle pouvant promouvoir l’activité physique. Les recherches portant sur la relation entre l’utilisation de l’automobile et l’activité physique utilisent typiquement une variable catégorielle pour décrire le mode de transport, tiennent peu compte du motif de déplacement et n’explorent pas la variation de l’association selon le lieu de résidence. Cette étude utilise à la fois l'activité physique auto-rapportée et objectivement mesurée pour tester l'association entre l’utilisation de l’automobile et l’activité physique totale, tout en tenant compte de ces limitations antérieures. Méthode: Les données de 780 participants provenant de la branche montréalaise de l’étude INTERACT (2018-2019) ont été analysées. Des modèles de régression linéaire ont été construits afin d’examiner la relation entre l’utilisation de l’automobile et l'activité physique modérée-vigoureuse (APMV) totale (auto-rapportée avec transformation logarithmique et objectivement mesurée). Ensuite, le motif de déplacement a été inclus dans ces modèles. Enfin, une régression pondérée géographiquement a permis d’explorer la variation spatiale de l'association entre l’usage de l’automobile et l’APMV. Résultats: La proportion des déplacements effectués en automobile est associée négativement avec l'APMV totale auto-rapportée (coefficient : -0,009, intervalle de confiance à 95% : -0,012 à -0,006) et objectivement mesurée (Coefficient : -0,29 minute par jour, intervalle de confiance à 95% : -0,55 à -0,03). La régression pondérée géographiquement indique une faible variation spatiale de l'association entre l'utilisation de l’automobile et l’APMV totale auto-rapportée. Le nombre de déplacements pour un motif tel que commerce et services est associé à l'APMV totale. Conclusion: Cette étude transversale a démontré une association négative entre l’utilisation de l’automobile et l’APMV totale sur le territoire montréalais. Certains motifs de déplacement sont associés à l’activité physique totale. / Background: Car usage reduction has previously been pointed out to be a population-based intervention promoting physical activity. Previous literature on the car usage-physical activity relation typically uses categorical variables for transport modes, rarely accounts for trip purpose and does not explore the influence of home location on this association. This study uses both self-reported and objectively measured physical activity to test the association between car usage and total daily physical activity, while accounting for previous limitations. Methods: INTERACT data collected in 2018-2019 among 780 participants from the Montreal metropolitan area site were analysed. Linear regression models of self-reported (log-transformed) and objectively measured total moderate-vigorous physical activity (MVPA) were built separately, as a function of car usage. Trip purpose was then included in these models. Finally, a geographically weighted regression (GWR) model was built to explore the spatial variation of the car usage-MVPA association. Results: The proportion of trips made by car showed a negative association with both self-reported (coefficient: -0.009, 95% CI [-0.012, -0.006]) and objectively measured (coefficient: -0.29 minutes per day, 95% CI [-0.55, -0.03]) total MVPA. GWR showed little spatial variation in the car usage-total self-reported MVPA. The number of trips toward certain purposes (e.g. “shops and services”) is associated with total MVPA. Conclusion: This cross-sectional study showed a negative association between car usage and total MVPA in the Montreal metropolitan area. Some trip purpose is associated with total physical activity.
419

Využití CHKO Brdy ve výuce přírodopisu a biologie / Use of the Brdy PLA in High-School Science Teaching

Valterová, Bára January 2021 (has links)
Presented work studies the possibilities of recently established protected landscape area (PLA) Brdy for a systematic use in teaching nature and biology related subjects at schools closely neighboring the PLA. The theoretical part of this diploma work makes a resume of basic information regarding the legal status of PLA's and introduces the reader into main facts about the PLA Brdy focusing on its natural aspects and specifics. General methods of education are reviewed briefly, followed by a more detailed discussion about the educational form of field trip and about possibilities how such trips or excursions to the PLA Brdy can be used in the education practice. The key part of this work is a relatively large questionnaire research for teachers, pupils and students of elementary and secondary schools next to Brdy. It establishes a database of their approaches to and existing experiences with field trips generally and excursions into PLA Brdy in particular. Two separate questionnaires have been used: one for teachers (16 questions, 26 respondents) and another one for pupils and students (30 questions, 152 respondents). Therefore, the database is composed of nearly 5000 responses which have been analyzed. The results show that interviewed pupils and students are clearly interested in the nature and...
420

Real-time audio processing for an embedded Linux system using a dual-kernel approach

Kulkarni, Nitin January 2017 (has links)
Professional audio processing systems such as digital musical instruments, audiomixers, etc. must operate with very tight constraints on overall processing latencyand CPU performance. Consequently, traditional implementations are still mostlybased on specialized hardware like Digital Signal Processors (DSP) and Real-TimeOperating Systems (RTOS) to meet such requirements. However, such systems areminimalistic in nature and they lack many features (e.g. network connectivity, widehardware support, etc.) that a general-purpose operating system such as Linuxoffers. Linux is a very popular choice for the operating system used in embeddeddevices, and many developers have started to use it for designing real-time systemswith relaxed timing constraints. However, none of the available solutions using astandard Linux kernel can satisfy the low-latency requirements of professional audiosystems.In this thesis, a dual kernel approach is employed to enable an embedded Linuxsystem to process audio with low roundtrip latency. The solution is developed usingthe Xenomai framework for real-time computation, which is based on a techniqueknown as interrupt pipeline (I-pipe). I-Pipe enables interrupt virtualization througha micro-kernel running between the Linux kernel and the interrupt controller hardware.The designed system includes an x86 Atom System-on-Chip (SoC), an XMOSmicrocontroller and audio converters to and from the analog domain. Custom kerneldrivers and libraries have been developed to expose the audio programming functionalitiesto programs running in user-space. As a result, the system can achieverobust real-time performance appropriate for professional audio applications, andat the same time it has all the advantages of a traditional Linux solution such ascompatibility with external devices and ease of programming. The real-time capabilityis measured by evaluating the performance in terms of worst case responsetime of the real-time tasks in comparison to the same metrics obtained under astandard Linux kernel. The overall roundtrip latency of audio processing is showedto be improved by almost an order of magnitude (around 2.5ms instead of 20ms). / Profesionella system för ljudbearbetning, som digitala musikinstrument, mixerbord,etc, arbetar med väldigt hårda krav på tidfördröjning och CPU-prestanda. Som enkonsekvens har dessa system traditionellt implementerats på specialiserad hårdvarasom specifika DSP-processor och speciella realtidsoperativsystem. Den typen avsystem är till sin natur minimalistiska och saknar många funktioner (till exempelnätverk och brett stöd för olika hårdvaror) som mer generella operativsystem,som Linux, kan erbjuda. Linux är ett väldigt populärt val av operativsystem förinbyggda system och många utvecklare har även börjat använda det till realtidssystemmed mindre hårda tidskrav. Det finns dock idag inte någon lösning med enstandard-linuxkärna som kan tillfredsställda de krav på låg fördröjning som krävsför användning i profesionella ljudsystem.I det här examensarbetet används en dubbelkärneuppsättning för att ge ettinbyggt Linuxsystem möjlighet att bearbeta digitalt ljud med låg fördröjning. Lösningenanvänder Xenomai-ramverket för realtidsberäkningar baserat på en teknikkallad interrupt pipeline (I-pipe). I-pipe ger möjlighet att virtualisera interruptgenom en mikrokärna som körs som ett lager mellan Linuxkärnan och hårdvaransinterruptcontroller.Det resulterande systemet inkluderar ett x86 Atom-enchipssystem, en XMOSmicrocontroller, och ljudkonverterare till och från analoga ljud in- och utgångar.Drivrutiner och bibliotek utvecklas för att ge direkt tillgång till ljudfunktionerfrån applikationer. Systemet ges därmed robust realtidsprestanda som gör detlämpligt för profesionella ljudtillämpningar samtidigt som det behåller alla fördelarfrån ett traditionellt Linuxsystem, som kompabilitet med extern hårdvara och enklareapplikationsutveckling. Systemets realtidsprestanda utvärderas som den maximalauppmätta tidfördröjning vid realtidsberäkningar jämfört med motsvarandeberäkningar på en standardlinuxkärna. Resultaten visade på en förbättring på nästanen storleksordning (ca 2,5ms mot 20ms).

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