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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.
11

Om meningsfulla val i filmmusik

Svensson Sander, Leo January 2023 (has links)
Uppsatsen kommer handla om hur vi gör meningsfulla val i kompositionsprocessonav musik till film. Jag kommer undersöka vilka metoder som historiskt har använts,vilken praxis som uppstått och varför, och försöker i mitt eget arbete hitta alternativa vägar framåt. Vidare undersöker jag hur vi medvetet och omedvetet arbetar med förväntan och hur den arbetar i oss, hur imperfektion och sårbarhet i konstnärliga uttryck kan hänga ihop med empati och mänsklighet, och metoder för att skapa inre logik och kreativa begränsningar i min egen skapandeprocess. / <p>Till uppsatsen bifogas ett filmklipp ur processen med en slutproduktion från Stockholms konstnärliga högskola, "Tyst symfoni", av Astrid Ahlbom Andersson.</p>
12

Computer modeling of flow lines and flaw migration in bulk deformation processes

Hattangady, Nitin V. January 1987 (has links)
No description available.
13

The mechanism of leak-before-break fracture and its application in engineering critical assessment

Bourga, Renaud January 2017 (has links)
This thesis investigated the different aspects and mechanisms of leak-before-break (LBB) assessment. The main objective was to improve the understanding of the transition between surface and through wall defects. While existing procedures generally idealise the through-wall crack into a rectangular shape, in reality a crack propagates with a shape depending on the loading. Comparison between the related solutions from established procedures have been undertaken. The apparent variation depending on the solutions used in the assessment has been highlighted. Two different methodologies have been employed to investigate the transition of flaw: (i) non-ideal through-wall and (ii) surface-breaking flaw propagation. The first approach consists of numerical models of non-idealised flaws in order to assess the effect on LBB parameters. For the second approach, experiments have been first carried out to visualise the shape of defect growths. To further study surface-breaking flaws, both experimental and numerical studies were performed. Fatigue tests on deeply notched plates with two crack aspect ratios were carried out. Strain evolutions on the back surface were recorded along the axes parallel and perpendicular to the crack. Numerical models have been prepared to investigate a larger scope. Behaviour of growing surface-breaking defects was examined. Based on the work conducted in this research, the major findings can be summarised as follows: - The existing solutions to carry out a LBB assessment using available procedures were reviewed and discussed. For axial flaws, SIF solutions were found similar and in good agreement with FEA values. Reference stress solutions showed significant difference between BS 7910 and API 579-1/ASME FFS-1. When compared to experimental data, API's solutions were able to distinguish between leak and break cases. - Flaw geometry assumption for through-wall crack yet to become idealised did not always reflect the actual behaviour, especially for COA calculation. In this case, FEA can be used as a good predictive tool for LBB to estimate margins when assessing leak rate. - The experiment using metallic specimens showed that high stress/strain on back surface would provide a good estimate of the crack propagation as it approached break-through. This offers a more accurate monitoring mechanism. Strain-mapping devices such as gauges could be used.
14

Fretting behavior of AISI 301 stainless steel sheet in full hard condition

Hirsch, Michael Robert 10 July 2008 (has links)
Fretting, which can occur when two bodies in contact undergo a low amplitude relative slip, can drastically reduce the fatigue performance of a material. The extent of fretting damage is dependent on the material combination and is affected by many parameters, making it difficult to design against fretting. Some of these parameters include contact force, displacement amplitude, and contacting materials. This work develops a method for quantifying the extent of damage from fretting as a function of these parameters for a thin sheet of AISI 301 stainless steel in the full hard condition in contact with both ANSI A356 aluminum and AISI 52100 steel contacting bodies. Fretting experiments were conducted on a Phoenix Tribology DN55 Fretting Machine using a fixture which was developed for holding thin specimens. The displacement amplitude and normal force were systematically varied in order to cover a range that could typically be experienced during service. The tribological behavior was studied by analyzing friction force during cycling and inspecting the resulting surface characteristics. Fretting damaged specimens were cycled in tension in a servohydraulic test system to failure. The decrease in fatigue life caused by fretting damage was determined by comparing the stress-life (S-N) response of the fretted specimens to the S-N response of the virgin material, thus characterizing the severity of the fretting damage. The conditions that lead to the greatest reduction in life were identified in this way. Using the fracture mechanics based NASGRO model, an Equivalent Initial Flaw Size (EIFS) was used to quantify the level of fretting damage, thus separating the life of the component into crack nucleation and subsequent propagation. This method and data will allow engineers to design more robust components that resist fretting damage, thus increasing the safety and reliability of the system.
15

Fins tragiques : poétique et éthique du dénouement dans la tragédie pré-moderne en Italie, en France et en Espagne / Tragic endings : the poetics and the ethics of the denouement in early modern Italian, Spanish and French tragedy

Zanin, Enrica 27 October 2010 (has links)
La poétique du dénouement pré-moderne, dans les tragédies italiennes, françaises et espagnoles, est liée à un souci éthique: la fin de l'intrigue est le lieu attendu qui en dévoile le sens et qui dit sa morale. Or, le dénouement tragique répond à une double exigence: s'il conclut la tragédie, il doit aussi renverser le sort du héros. Pour achever la tragédie, le dénouement doit réaliser un équilibre moral; pour renverser l'intrigue, il doit susciter un excès pathétique. Ces deux exigences sont issues de deux modèles théoriques opposés: la logique de l'exemplarité et l'efficacité pathétique. La thèse analyse les stratégies poétiques que théoriciens et dramaturges mettent en place pour concilier ces deux modèles poétiques, au sein des trois critères qui définissent le dénouement (son orientation, ses modalités et sa structure) et des problèmes éthiques qu'ils posent (l'enchaînement de la causalité, la faute et la rétribution du héros). Les efforts pour concilier exemplarité et pathétique se soldent par un échec. En dépit de leurs différences, les trois traditions nationales dénoncent les faiblesses de la logique de l'exemplarité, qui ne permet pas de justifier, par une règle de conduite universelle, l'expérience du malheur, du désordre, de l'injustice. Le dénouement tragique incite alors le spectateur à un déchiffrement herméneutique pour trouver des raisons à la misère inexplicable du héros, que manifeste le renversement de fortune. / The poetics of early modern denouement in Italian, Spanish and French tragedies implies an ethical issue. The ending of the plot is the expected climax which reveals the meaning and the moral of the story. The aim of the tragic denouement is twofold: it concludes the play and it reverses the hero's fate. In order to conclude the tragedy, the denouement restores a moral balance; in order to reverse the plot, it gives rise to a pathetic excess. Two divergent theoretical models underlie this dual requirement: the logic of exemplarity and the poetics of pathos. I propose to examine the strategies displayed by theorists and dramatists in order to bring together these two theoretical models. I therefore consider the three main features of the denouement (its direction, mode and structure) and the ethical issues to which they give rise (the sequence of causality, the tragic flaw and its atonement). The conciliation between exemplarity and pathos proves an impossibility: Italian, Spanish and French tragedy, despite their differences, denounce the logic of exemplarity as inadequate and unfit to justify, through the expression of a theoretical rule, the experience of misfortune, injustice and chaos. The tragic denouement leads the spectator to a hermeneutic deciphering that may uncover the reasons for the hero's inexplicable misfortunes.
16

Nízkoteplotní zkoušky a lomová houževnatost vybraných keramických materiálů / Low temperature tests and fracture toughness of selected ceramic materials

Beck, Branislav January 2015 (has links)
Diploma thesis deals with the determination of fracture toughness values of sintered silicon carbide and casted basalt using both the Single Edge V-Notch Beam (SEVNB) and the Chevron Notched Beam (CNB) methods at room and cryogenic temperatures. The first part of this thesis offers general overview and categorization of ceramic materials. Fracture mechanics of the ceramic materials and available fracture toughness testing methods are discussed in following chapters. The last section in the theoretical part is aimed to the microstructure and properties of the silicon carbide. Experimental part of the work summarizes methods used for characterization of selected materials from the microstructural and fracture point of view. Preparation of samples for microstructural observation and samples for fracture toughness determination are described in details. The results of the fracture toughness data for sintered silicon carbide and cast-basalt obtained at room temperature and at -100 °C are displayed. Consideration of possible measurements errors and application of various fracture toughness testing methods are discussed in the next chapter of this work. The difference in the fracture toughness values with the decrease of testing temperature was found. The difference depends on both, the used method of fracture toughness determination and the material used for the tests. The most important results gained during the experimental work are summarized in the chapter “Conclusions”.
17

Tragik in Werken Dürrenmatts

Horne, Brigitte Katharina 11 1900
Text in German / Friedrich Durrenmatt hat die meisten seiner Dramen als Komodien oder Tragikomodien bezeichnet, da er davon uberzeugt war, daB es unmoglich sei, in der heutigen Zeit noch Tragodien zu schreiben. Diese Arbeit versucht am Beispiel einiger dramatischer Werke Durrenmatts zu zeigen, daB der Autor der "Physiker", der "Panne" und anderer Stucke, vor allem des "Besuchs der alten Dame", in weit hoherem MaBe der griechischen Tragodie verpflichtet war, als er erkannte oder zugeben wollte / Friedrich Durrenmatt has described most of his dramas either as comedies or as bitter comedies for he firmly believed that it was not suitable to write tragedies in our modern times. This paper was written to prove with the help of a few examples that the author of "The Physicists", "The Puncture" and others especially "The Visit" - was more bound to the classical Greek form of tragedy than he recognized or admitted / Linguistics and Modern Languages / M.A. (German)
18

Kartläggning av OFP och defektrelaterade parametrar : Inriktning på termisk utmattning / Mapping of NDT and flaw related parameters : Focus on thermal fatigue

Larsson, Niklas January 2006 (has links)
<p>I både kvalitets- och kontrollarbete finns det behov att kunskapsmässigt komma så nära verkligheten som möjligt vid fastställande av defektparametrar för oförstörande provning (OFP). Orsaken är att olika acceptanskrav och bedömningsgränser är svåra att klarlägga när man inte kan förlita sig på att uppgifter är realistiska. I projektet har olika erfarenheter använts för att få en bättre helhetsbild i området för defektparametrar och oförstörande provning.</p><p>Denna rapport redovisar den inledande delen av forskning och utvecklingsprojektet PLANT 2, där olika defektparametrar kartlagts och en teoretisk bedömning utförts med avseende på hur signalsvaret påverkas för OFP-metoderna virvelström (ET) och ultraljudsprovning (UT) i form av puls-eko (PE) och ”time-of-flight-diffraction” (TOFD).</p><p>Definitionen av redovisade defektparametrar följer i stort SKI-rapport 95:70 [1]. Defektparametrar i denna rapport redovisas i bilaga 1.</p><p>Vid bedömningen av defektparametrarnas inverkan på OFP-tekniker, har drift¬inducerande defekter och tillverkningsdefekter hanterats separat. För de driftinducerande defekterna delades bedömningen upp i en generell och en specifik bedömning. De defektparametrar som bedöms specifikt och klassats att påverka signalsvaret betydligt bör vara av mest intresse i nästkommande etapp. Följande defektparametrar bedömdes påverka signalsvaret betydligt:</p><p>• Form i ytan, antal sprickor och avstånd i gatstensmönster</p><p>(vid termisk ut¬mattning)</p><p>• Form i djupled</p><p>• Sprickbredd vid sprickspets och sprickspetsradie</p><p>För tillverkningsdefekter bedömdes defektparametrarnas form i djupled och geometri påverka signalsvaret betydligt för defekttyperna slagg och bindfel.</p><p>Vid utvärdering av UT-PE och UT-TOFD teknikerna överensstämde resultatet helt med den teoretiska bedömningen. För ET-tekniken stämde endast en av tre defektparametrar överens med den teoretiska bedömningen.</p> / <p>In quality control of defect parameters for Non-Destructive Testing (NDT) it’s essential to have good knowledge about the defects. The reason is that different acceptance criteria and assessments must be based on defects that correspond to real defects. In this project different experience has been analyzed to get a better overview between defect parameters and non-destructive testing.</p><p>This report shows the beginning of the research & development project PLANT 2. There are different flaw parameters that have been mapped and a theoretical assessment has been performed with regard to how the signal response is influenced by the NDT techniques eddy current, ultrasonic pulse echo and ultrasonic time-of-flight-diffraction.</p><p>The definition of the reported flaw parameters does in general follow the one presented in SKI-report 95:70 [1]. The actual flaw parameters in this report are presented in appendix 1.</p><p>In the assessment of the influences on the NDT techniques with regard to flaw parameters, service-induced flaws and manufactured flaws have been separated in to two categories. The service-induced flaws have further on been separated in a general and a specific assessment. Those flaw parameters that have been assessed to be specific and classified to influence the signal response considerably should be the ones of most interest in future studies. The following flaw parameters were assessed to affect the signal response considerably:</p><p>• Macroscopic shape in the surface direction, number of cracks</p><p>and cobblestone stone pattern distance (for thermal fatigue)</p><p>• Macroscopic shape in the through thickness direction</p><p>• Crack width at the crack tip and the crack tip radius</p><p>For flaws caused by the manufacturing process, type slag and lack of fusion, the flaw parameters “Macroscopic shape in the through thickness direction” and “the geometry” were influenced by the signal response considerably.</p><p>In the evaluation of signal response with the UT pulse echo and UT TOFD techniques, the result corresponded to the theoretical assessment. For the eddy current technique only one of three flaw parameters corresponded to the theoretical assessment.</p>
19

Kartläggning av OFP och defektrelaterade parametrar : Inriktning på termisk utmattning / Mapping of NDT and flaw related parameters : Focus on thermal fatigue

Larsson, Niklas January 2006 (has links)
I både kvalitets- och kontrollarbete finns det behov att kunskapsmässigt komma så nära verkligheten som möjligt vid fastställande av defektparametrar för oförstörande provning (OFP). Orsaken är att olika acceptanskrav och bedömningsgränser är svåra att klarlägga när man inte kan förlita sig på att uppgifter är realistiska. I projektet har olika erfarenheter använts för att få en bättre helhetsbild i området för defektparametrar och oförstörande provning. Denna rapport redovisar den inledande delen av forskning och utvecklingsprojektet PLANT 2, där olika defektparametrar kartlagts och en teoretisk bedömning utförts med avseende på hur signalsvaret påverkas för OFP-metoderna virvelström (ET) och ultraljudsprovning (UT) i form av puls-eko (PE) och ”time-of-flight-diffraction” (TOFD). Definitionen av redovisade defektparametrar följer i stort SKI-rapport 95:70 [1]. Defektparametrar i denna rapport redovisas i bilaga 1. Vid bedömningen av defektparametrarnas inverkan på OFP-tekniker, har drift¬inducerande defekter och tillverkningsdefekter hanterats separat. För de driftinducerande defekterna delades bedömningen upp i en generell och en specifik bedömning. De defektparametrar som bedöms specifikt och klassats att påverka signalsvaret betydligt bör vara av mest intresse i nästkommande etapp. Följande defektparametrar bedömdes påverka signalsvaret betydligt: • Form i ytan, antal sprickor och avstånd i gatstensmönster (vid termisk ut¬mattning) • Form i djupled • Sprickbredd vid sprickspets och sprickspetsradie För tillverkningsdefekter bedömdes defektparametrarnas form i djupled och geometri påverka signalsvaret betydligt för defekttyperna slagg och bindfel. Vid utvärdering av UT-PE och UT-TOFD teknikerna överensstämde resultatet helt med den teoretiska bedömningen. För ET-tekniken stämde endast en av tre defektparametrar överens med den teoretiska bedömningen. / In quality control of defect parameters for Non-Destructive Testing (NDT) it’s essential to have good knowledge about the defects. The reason is that different acceptance criteria and assessments must be based on defects that correspond to real defects. In this project different experience has been analyzed to get a better overview between defect parameters and non-destructive testing. This report shows the beginning of the research &amp; development project PLANT 2. There are different flaw parameters that have been mapped and a theoretical assessment has been performed with regard to how the signal response is influenced by the NDT techniques eddy current, ultrasonic pulse echo and ultrasonic time-of-flight-diffraction. The definition of the reported flaw parameters does in general follow the one presented in SKI-report 95:70 [1]. The actual flaw parameters in this report are presented in appendix 1. In the assessment of the influences on the NDT techniques with regard to flaw parameters, service-induced flaws and manufactured flaws have been separated in to two categories. The service-induced flaws have further on been separated in a general and a specific assessment. Those flaw parameters that have been assessed to be specific and classified to influence the signal response considerably should be the ones of most interest in future studies. The following flaw parameters were assessed to affect the signal response considerably: • Macroscopic shape in the surface direction, number of cracks and cobblestone stone pattern distance (for thermal fatigue) • Macroscopic shape in the through thickness direction • Crack width at the crack tip and the crack tip radius For flaws caused by the manufacturing process, type slag and lack of fusion, the flaw parameters “Macroscopic shape in the through thickness direction” and “the geometry” were influenced by the signal response considerably. In the evaluation of signal response with the UT pulse echo and UT TOFD techniques, the result corresponded to the theoretical assessment. For the eddy current technique only one of three flaw parameters corresponded to the theoretical assessment.
20

Numerical Evaluation of Classification Techniques for Flaw Detection

Vallamsundar, Suriyapriya January 2007 (has links)
Nondestructive testing is used extensively throughout the industry for quality assessment and detection of defects in engineering materials. The range and variety of anomalies is enormous and critical assessment of their location and size is often complicated. Depending upon final operational considerations, some of these anomalies may be critical and their detection and classification is therefore of importance. Despite the several advantages of using Nondestructive testing for flaw detection, the conventional NDT techniques based on the heuristic experience-based pattern identification methods have many drawbacks in terms of cost, length and result in erratic analysis and thus lead to discrepancies in results. The use of several statistical and soft computing techniques in the evaluation and classification operations result in the development of an automatic decision support system for defect characterization that offers the possibility of an impartial standardized performance. The present work evaluates the application of both supervised and unsupervised classification techniques for flaw detection and classification in a semi-infinite half space. Finite element models to simulate the MASW test in the presence and absence of voids were developed using the commercial package LS-DYNA. To simulate anomalies, voids of different sizes were inserted on elastic medium. Features for the discrimination of received responses were extracted in time and frequency domains by applying suitable transformations. The compact feature vector is then classified by different techniques: supervised classification (backpropagation neural network, adaptive neuro-fuzzy inference system, k-nearest neighbor classifier, linear discriminate classifier) and unsupervised classification (fuzzy c-means clustering). The classification results show that the performance of k-nearest Neighbor Classifier proved superior when compared with the other techniques with an overall accuracy of 94% in detection of presence of voids and an accuracy of 81% in determining the size of the void in the medium. The assessment of the various classifiers’ performance proved to be valuable in comparing the different techniques and establishing the applicability of simplified classification methods such as k-NN in defect characterization. The obtained classification accuracies for the detection and classification of voids are very encouraging, showing the suitability of the proposed approach to the development of a decision support system for non-destructive testing of materials for defect characterization.

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