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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.
501

Die herskepping van lewensdrome na `n verlies: `n Gestalt perspektief

Von Wielligh, Belinda 30 June 2006 (has links)
Summaries in English and Afrikaans / Any loss in an adolescent's life may lead to shattered dreams. Therapists, who work with adolescents who have experienced a loss must support and guide them to develop an awareness of their needs, impulses and dreams. Therapists must furthermore be aware of the factors that contributed to a turning point for the adolescents who managed to recreate their dreams. Adolescents' dreams are influenced by the current circumstances in South Africa, as well as their parents' perceptions and parenting styles. The loss of what could have been, after a loss, must also be addressed. The gestalt therapist establishes the process of awareness in the here-and-now. Furthermore, the adolescent must be guided to accept responsibility for his own choices and to purposeful create a new life dream. / Enige verlies in adolessente se lewens kan lei tot verbrokkelde lewensdrome. Terapeute wat werk met adolessente wat 'n verlies ervaar het, moet hul ondersteun en begelei sodat hulle bewustheid kan ontwikkel van hul behoeftes, drange en drome. Terapeute moet verder bewus wees van die faktore wat 'n keerpunt meegebring het by die adolessente wat wei hul drome kon herskep. Adolessente se lewensdrome word beinvloed deur die huidige omstandighede in Suid-Afrika, sowel as deur hul ouers se persepsies en ouerskapstyl. Die verlies aan dit wat kon wees, na afloop van 'n verlies moet dus ook aangespreek word. Die gestaltterapeut bewerkstellig die bewusmakingsproses in die hier-en-nou. Verder moet die adolessent gelei word om verantwoordelikheid te neem vir sy eie keuses en om doelbewus 'n nuwe lewensdroom te skep. / Social Work / M. Diac. (Play Therapy)
502

Both temple and tomb: difference, desire and death in the sculptures of the Royal museum of central Africa

Morris, Wendy Ann 30 November 2003 (has links)
Both Temple and Tomb is a dissertation in two parts. The first part is an examination and analysis of a collection of 'colonial' sculptures on permanent display in the Royal Museum of Central Africa in Tervuren Belgium. The second part is a reflection on the author's own paintings, drawings and film and an examination of the critical potential of these images in challenging the colonial narratives of the RMCA. Part I presents two arguments. The first is that European aesthetic codes have been used to legitimize the conquest of the Congo and to award sanction to a voyeuristic gaze. The second is that the organization of the sculptures of Africans (and European females) into carefully managed spaces and relationships results in the creation of erotically-charged formations that are intended to afford pleasure to male European spectators. Part II examines the strategies used in Re-Turning the Shadows to disrupt (neo)colonial patterns of viewing that have become ritual and 'naturalized'. Against RMCA narratives that pay homage to the objectivity of science and research, the paintings and film present images that explore multiple subjectivities, mythologizing impulses, and metaphoric allusions. / Art History, Visual Arts and Musicology / M.A. (Visual Arts)
503

Turning left : counter-hegemonic exhibition-making in the post-socialist era (1989-2014)

Wray, Lynn Marie January 2016 (has links)
This research examines how the practice of curating has been used to further counter-hegemonic agendas in public art institutions since 1989. The central aim is to provide a fuller, contextualised, and medium specific understanding of the how the institutional exhibition might be used to challenge the hegemony of neoliberalism and the post-political consensus politics that sustains its dominance. It provides insights, through both historic case studies and reflective practice, that problematise the idea that the institutional art exhibition is a viable medium for counter-hegemonic critique, or represents the ideal space for the development of an agonistic public discourse. This thesis presents collaborative research undertaken with Tate Liverpool and Liverpool John Moores University. The research presented both extrapolated from, and contributed to, the development of an exhibition, co-curated with Tate Liverpool, entitled Art Turning Left (8 November 2013 – 2 February 2014) and a supplementary publication of the same name. The first section investigates how the idea that curators can counter neoliberal dominance, through institutional exhibition-making, developed. It draws from analyses of previous exhibitions, and the theory of Chantal Mouffe, in order to critically evaluate the curatorial application of counter-hegemonic critique and agonistic practice. It also provides a review of how exhibitions (held in major art institutions since 1989) have articulated politics, in order to determine their relationship to neoliberal dominance, and to identify significant gaps in the dialogue facilitated by these institutions. These analyses provides the theoretical and contextual grounding for the final two chapters, which provide a rationale and critical evaluation of my own attempt to develop an alternative counter-hegemonic curatorial strategy for the exhibition at Tate Liverpool. They document, and analyse, the areas of dissensus, and the ideological and pragmatic limitations that emerged, in trying to realise these theoretical propositions (in practice) in a public art museum. The thesis therefore provides a critical framework for the development of an alternative practice that positions the exhibition as a form of post-political critique and specifically targets the hegemonic role that institutional exhibitions play in reinforcing class distinctions and devaluing nonprofessional creativity.
504

Modélisation de l'intégrité des surfaces usinées : Application au cas du tournage finition de l'acier inoxydable 15-5PH

Mondelin, Alexandre 05 December 2012 (has links)
En usinage, la zone de coupe présente des conditions de température, des cinétiques thermiques, des déformations et des pressions extrêmes. Dans ce contexte, être capable de relier les variations des conditions de coupe (vitesse de coupe, avance, lubrification, usure, outil,…) à l’intégrité de la surface usinée constitue un objectif scientifique majeur. Cette thèse s’intéresse au cas du tournage finition du 15-5PH (acier inoxydable martensitique utilisé, entre autre, pour la fabrication des pièces de rotor d’hélicoptère ainsi que les pompes et les vannes de circuit primaire de centrale nucléaire) et s’inscrit dans le cadre du projet MIFSU (Modélisation de l’Intégrité et de la Fatigue des Surfaces Usinées).Dans un premier temps, le comportement du matériau a été étudié afin d’alimenter les simulations d’usinage. Des essais de dilatométrie libre ont été conduit afin de calibrer les cinétiques d’austénitisation du 15-5PH pour des vitesses de chauffe élevées (jusqu’à 11000 °C/s). Les paramètres du modèle de changement de phase de Leblond ont alors été identifiés. De plus, des essais de compression dynamique (dε/dt allant de 0.01 à 80 /s et ε > 1) ont été réalisés pour calibrer une loi de comportement élasto-plastique aux grandes déformations avec une sensibilité à la vitesse de déformation. Ces essais ont aussi permis de mettre en évidence des phénomènes de recristallisation dynamique et leurs influences sur la contrainte d’écoulement du matériau. Un modèle de recristallisation dynamique a donc également été mis en œuvre.En parallèle, un modèle numérique de prédiction de l’intégrité des surfaces tournées a été construit. Ce modèle repose sur une méthodologie dite « hybride » (développée au cours de la thèse Frédéric Valiorgue pour l’acier AISI 304L) qui consiste à supprimer la modélisation de l’outil de coupe et de la formation du copeau, et à remplacer l’impact thermomécanique de ces derniers sur la surface usinée par des chargements équivalents. Une étape de calibration de ces chargements a donc été réalisée à travers des essais de coupe orthogonale et de frottement (étude de sensibilité des efforts d’usinage, du coefficient de frottement et du coefficient de partage thermique) aux variations des paramètres de coupe.Enfin, les résultats des simulations numériques de tournage portant sur la prédiction des changements de microstructure (austénitisation et recristallisation dynamique) ainsi que des contraintes résiduelles ont été comparés aux résultats issus d’une campagne d’essais de chariotage. / During machining, extreme conditions of pressure, temperature and strain appear in the cutting zone. In this thermo-mechanical context, the link between the cutting conditions (cutting speed, lubrication, feed rate, wear, tool coating…) and the machining surface integrity represents a major scientific target. This PhD study is a part of a global project called MIFSU (Modeling of the Integrity and Fatigue resistance of Machining Surfaces) and it focuses on the finish turning of the 15-5PH (a martensitic stainless steel used for parts of helicopter rotor). Firstly, material behavior has been studied in order to provide data for machining simulations. Stress-free dilatometry tests were conducted to obtain the austenitization kinetics of 15-5PH steel for high heating rates (up to 11,000 ° C/s). Then, parameters of Leblond metallurgical model have been calibrated. In addition, dynamic compression tests (dε/dt ranging from 0.01 to 80/s and ε > 1) have been performed to calibrate a strain-rate dependent elastoplasticity model (for high strains). These tests also helped to highlight the dynamic recrystallization phenomena and their influence on the flow stress of the material. Thus, recrystallization model has also been implemented.In parallel, a numerical model for the prediction of machined surface integrity has been constructed. This model is based on a methodology called "hybrid" (developed during the PhD thesis of Frédéric Valiorgue for the AISI 304L steel). The method consists in replacing tool and chip modeling by equivalent loadings (obtained experimentally). A calibration step of these loadings has been carried out using orthogonal cutting and friction tests (with sensitivity studies of machining forces, friction and heat partition coefficients to cutting parameters variations).Finally, numerical simulations predictions of microstructural changes (austenitization and dynamic recrystallization) and residual stresses have been successfully compared with the results of an experimental campaign of turning.
505

Dopady regulace porodnosti na růst čínské ekonomiky / The Implications of Family Planning Policies on the Growth of Chinese Economy

Skořepová, Kateřina January 2013 (has links)
Apart from rapid economic growth, China has also experienced significant demographic changes over the past few decades. The People's Republic of China's family planning policies led to a sharp drop in the fertility rate. This MS Thesis aims to assess the possible consequences of the family planning policies on future growth of Chinese economy. The theoretical part defines population policy, assess the connections between population growth and economic growth and deals with the development of population theory over the years. The analytical part describes the family planning policy in China, its principles and instruments. Next it identifies the possible consequences of the demographic changes caused by the drop in fertility rate. The last part of the thesis focuses on two economically most severe consequences - population ageing and shrinking working age population - and evaluates its implications on future growth of Chinese economy.
506

Variantní řešení MÚK Mohelnice sever / Grade-separated interchange Mohelnice-north - Study

Lukáš, Radek January 2019 (has links)
This diploma thesis deals with the proposal of an alternative solution to the intersection of Mohelnice North crossroads. It compares the current junction design, which is considered inappropriate, with two new proposals for circular intersections. The aim of the thesis is to propose the resultant junction cheaper, smaller and simpler for users.
507

Konstrukce frézovací hlavy pro CNC soustruh s nastavitelným sklonem / Design of CNC lathe milling head with adjustable tilt

Horák, Vítězslav January 2020 (has links)
This thesis deals with design of CNC lathe milling head with B axis. Thesis includes research in CNC turning machines, their tool systems and overview of manufacturers of milling B axis. It also includes calculation of machining forces, design of spindle and design of B axis including necessary calculations. Part of this thesis is also 3D model and assembly drawing, 2 manufacturing drawings and list of items.
508

Dynamické vlastnosti osy C pro multifunkční soustružnické centrum / Dynamic Behaviours of the C Axis Drive for Multifunction Cutting Center

Křepela, Jan January 2011 (has links)
his Disertation thesis involves the creating of the simulation model of the C axis drive over mentioned machine and them verification on the prototype of this machine. C axis is controlled with position feedback. Simulation model was created before the realisation of the machine prototype for the preliminary identification of the dynamic behaviours in the working cycles and them opportunity of the realisation this conception. C axis is constructed with worm gear and is controlled with help of Master-Slave drive. This torque drive eliminates the production backlash in the worm gear. The multifunction turning center, where is used this C axis, is determinate for heavy duty roughing cutting of the forged peaces, where is problem with dynamic stability of the cutting process. Simulation model includes the problems with multi-body mass system, friction on the worm gear, self locking, damping on the worm gear and the optimization of the parametrs for many regulators. Simulation model was verified on the prototype of the machine. Achieved results bring the new knowledge, which are used for simulation complicated machine nodes and this knowledge is used for research and developing of the similar mechatronics system.
509

Smart Sheet Music Reader for Android / Smart Sheet Music Reader for Android

Smejkal, Vojtěch January 2014 (has links)
Oblasti jako automatické otáčení stránek nebo automatický hudební doprovod jsou studovány již několik desetiletí. Tato práce shrnuje současné metody pro počítačové sledování not v reálném čase. Zabývá se také hudebními příznaky jako jsou chroma třídy a syntetizované spektrální šablony. Dále popisuje klíčové části systému jako krátkodobou Fourierovu transformaci a Dynamické borcení času. V rámci projektu byl navrhnut a vyvinut vlastní systém pro sledování pozice hráče v notách, který byl následně implementován jako mobilní aplikace. Výsledný systém dokáže sledovat i skladby s výrazně odlišným tempem, pauzami během hry nebo drobnými odchylkami od předepsaných not.
510

Advanced nonlinear stability analysis of boiling water nuclear reactors

Lange, Carsten 25 September 2009 (has links)
This thesis is concerned with nonlinear analyses of BWR stability behaviour, contributing to a deeper understanding in this field. Despite negative feedback-coefficients of a BWR, there are operational points (OP) at which oscillatory instabilities occur. So far, a comprehensive and an in-depth understanding of the nonlinear BWR stability behaviour are missing, even though the impact of the significant physical parameters is well known. In particular, this concerns parameter regions in which linear stability indicators, like the asymptotic decay ratio, lose their meaning. Nonlinear stability analyses are usually carried out using integral (system) codes, describing the dynamical system by a system of nonlinear partial differential equations (PDE). One aspect of nonlinear BWR stability analyses is to get an overview about different types of nonlinear stability behaviour and to examine the conditions of their occurrence. For these studies the application of system codes alone is inappropriate. Hence, in the context of this thesis, a novel approach to nonlinear BWR stability analyses, called RAM-ROM method, is developed. In the framework of this approach, system codes and reduced order models (ROM) are used as complementary tools to examine the stability characteristics of fixed points and periodic solutions of the system of nonlinear differential equations, describing the stability behaviour of a BWR loop. The main advantage of a ROM, which is a system of ordinary differential equations (ODE), is the possible coupling with specific methods of the nonlinear dynamics. This method reveals nonlinear phenomena in certain regions of system parameters without the need for solving the system of ROM equations. The stability properties of limit cycles generated in Hopf bifurcation points and the conditions of their occurrence are of particular interest. Finally, the nonlinear phenomena predicted by the ROM will be analysed in more details by the system code. Hence, the thesis is not focused on rendering more precisely linear stability indicators like DR. The objective of the ROM development is to develop a model as simple as possible from the mathematical and numerical point of view, while preserving the physics of the BWR stability behaviour. The ODEs of the ROM are deduced from the PDEs describing the dynamics of a BWR. The system of ODEs includes all spatial effects in an approximated (spatial averaged) manner, e.g. the space-time dependent neutron flux is expanded in terms of a complete set of orthogonal spatial neutron flux modes. In order to simulate the stability characteristics of the in-phase and out-of-phase oscillation mode, it is only necessary to take into account the fundamental mode and the first azimuthal mode. The ROM, originally developed at PSI in collaboration with the University of Illinois (PSI-Illinois-ROM), was upgraded in significant points: • Development and implementation of a new calculation methodology for the mode feedback reactivity coefficients (void and fuel temperature reactivity) • Development and implementation of a recirculation loop model; analysis and discussion of its impact on the in-phase and out-of-phase oscillation mode • Development of a novel physically justified approach for the calculation of the ROM input data • Discussion of the necessity of consideration of the effect of subcooled boiling in an approximate manner With the upgraded ROM, nonlinear BWR stability analyses are performed for three OPs (one for NPP Leibstadt (cycle7), one for NPP Ringhals (cycle14) and one for NPP Brunsbüttel (cycle16) for which measuring data of stability tests are available. In this thesis, the novel approach to nonlinear BWR stability analyses is extensively presented for NPP Leibstadt. In particular, the nonlinear analysis is carried out for an operational point (OP), in which an out-of-phase power oscillation has been observed in the scope of a stability test at the beginning of cycle 7 (KKLc7_rec4). The ROM predicts a saddle-node bifurcation of cycles, occurring in the linear stable region, close to the KKLc7_rec4-OP. This result allows a new interpretation of the stability behaviour around the KKLc7_rec4-OP. The results of this thesis confirm that the RAM-ROM methodology is qualified for nonlinear BWR stability analyses. / Die vorliegende Dissertation leistet einen Beitrag zum tieferen Verständnis des nichtlinearen Stabilitätsverhaltens von Siedewasserreaktoren (SWR). Trotz der Tatsache, dass in diesem technischen System nur negative innere Rückkopplungskoeffizienten auftreten, können in bestimmten Arbeitspunkten oszillatorische Instabilitäten auftreten. Obwohl relativ gute Kenntnisse über die signifikanten physikalischen Einflussgrößen vorliegen, fehlt bisher ein umfassendes Verständnis des SWR-Stabilitätsverhaltens. Das betrifft insbesondere die Bereiche der Systemparameter, in denen lineare Stabilitätsindikatoren, wie zum Beispiel das asymptotische Decay Ratio (DR), ihren Sinn verlieren. Die nichtlineare Stabilitätsanalyse wird im Allgemeinen mit Systemcodes (nichtlineare partielle Differentialgleichungen, PDG) durchgeführt. Jedoch kann mit Systemcodes kein oder nur ein sehr lückenhafter Überblick über die Typen von nichtlinearen Phänomenen, die in bestimmten System-Parameterbereichen auftreten, erhalten werden. Deshalb wurde im Rahmen der vorliegenden Arbeit eine neuartige Methode (RAM-ROM Methode) zur nichtlinearen SWR-Stabilitätsanalyse erprobt, bei der integrale Systemcodes und sog. vereinfachte SWR-Modelle (ROM) als sich gegenseitig ergänzende Methoden eingesetzt werden, um die Stabilitätseigenschaften von Fixpunkten und periodischen Lösungen (Grenzzyklen) des nichtlinearen Differentialgleichungssystems, welches das Stabilitätsverhalten des SWR beschreibt, zu bestimmen. Das ROM, in denen das dynamische System durch gewöhnliche Differentialgleichungen (GDG) beschrieben wird, kann relativ einfach mit leistungsfähigen Methoden aus der nichtlinearen Dynamik, wie zum Beispiel die semianalytische Bifurkationsanalyse, gekoppelt werden. Mit solchen Verfahren kann, ohne das DG-System explizit lösen zu müssen, ein Überblick über mögliche Typen von stabilen und instabilen oszillatorischen Verhalten des SWR erhalten werden. Insbesondere sind die Stabilitätseigenschaften von Grenzzyklen, die in Hopf-Bifurkationspunkten entstehen, und die Bedingungen, unter denen sie auftreten, von Interesse. Mit dem Systemcode (RAMONA5) werden dann die mit dem ROM vorhergesagten Phänomene in den entsprechenden Parameterbereichen detaillierter untersucht (Validierung des ROM). Die Methodik dient daher nicht der Verfeinerung der Berechnung linearer Stabilitätsindikatoren (wie das DR). Das ROM-Gleichungssystem entsteht aus den PDGs des Systemcodes durch geeignete (nichttriviale) räumliche Mittelung der PDG. Es wird davon ausgegangen, dass die Reduzierung der räumlichen Komplexität die Stabilitätseigenschaften des SWR nicht signifikant verfälschen, da durch geeignete Mittlungsverfahren, räumliche Effekte näherungsweise in den GDGs berücksichtig werden. Beispielsweise wird die raum- und zeitabhängige Neutronenflussdichte nach räumlichen Moden entwickelt, wobei für eine Simulation der Stabilitätseigenschaften der In-phase- und Out-of-Phase-Leistungsoszillationen nur der Fundamentalmode und der erste azimuthale Mode berücksichtigt werden muss. Das ROM, welches ursprünglich am Paul Scherrer Institut (PSI, Schweiz) in Zusammenarbeit mit der Universität Illinois (USA) entwickelt wurde, ist in zwei wesentlichen Punkten erweitert und verbessert worden: • Entwicklung und Implementierung einer neuen Methode zur Berechnung der Rückkopplungsreaktivitäten • Entwicklung und Implementierung eines Modells zur Beschreibung der Rezirkulationsschleife (insbesondere wurde der Einfluss der Rezirkulationsschleife auf den In-Phase-Oszillationszustand und auf den Out-of-Phase-Oszillationszustand untersucht) • Entwicklung einer physikalisch begründeten Methode zur Berechnung der ROM-Inputdaten • Abschätzung des Einflusses des unterkühlten Siedens im Rahmen der ROM-Näherungen Mit dem erweiterten ROM wurden nichtlineare Stabilitätsanalysen für drei Arbeitspunkte (KKW Leibstadt (Zyklus 7) KKW Ringhals (Zyklus 14) und KKW Brunsbüttel (Zyklus 16)), für die Messdaten vorliegen, durchgeführt. In der Dissertationsschrift wird die RAM-ROM Methode ausführlich am Beispiel eines Arbeitspunktes (OP) des KKW Leibstadt (KKLc7_rec4-OP), in dem eine aufklingende regionale Leistungsoszillation bei einem Stabilitätstest gemessen worden ist, demonstriert. Das ROM sagt die Existenz eines Umkehrpunktes (saddle-node bifurcation of cycles, fold-bifurcation) voraus, der sich im linear stabilen Gebiet nahe der Stabilitätsgrenze befindet. Mit diesem ROM-Ergebnis ist eine neue Interpretation der Stabilitätseigenschaften des KKLc7_rec4-OP möglich. Die Resultate der in der Dissertation durchgeführten RAM-ROM Analyse bestätigen, dass das weiterentwickelte ROM für die Analyse des Stabilitätsverhaltens realer Leistungsreaktoren qualifiziert wurde.

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