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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.
1

Optimization Under Uncertainty of Nonlinear Energy Sinks

Boroson, Ethan Rain January 2015 (has links)
Nonlinear Energy Sinks (NESs) are a promising technique for passively reducing the amplitude of vibrations. Through nonlinear stiffness properties, a NES is able to passively absorb energy. Unlike a traditional Tuned Mass Damper (TMD), NESs do not require a specific tuning and absorb energy from a wide range of frequencies. However, each NES is only efficient over a limited range of excitations. In addition, NES efficiency is extremely sensitive to perturbations in design parameters or loading, demonstrating a nearly discontinuous efficiency. Therefore, in order to optimally design a NES, uncertainties must be accounted for. This thesis focuses on optimally selecting parameters to design an effective NES system through optimization under uncertainty. For this purpose, a specific algorithm is introduced that makes use of clustering techniques to segregate efficient and inefficient NES behavior. SVM and Kriging approximations as well as new adaptive sampling techniques are used for the optimization under uncertainty. The variables of the problems are either random design variables or aleatory variables. For example, the excitation applied to the main vibrating system is treated as aleatory. In an effort to increase the range of excitations for which NESs are effective, a combination of NESs configured in parallel is considered. Optimization under uncertainty is performed on several examples with varying design parameters as well as different numbers of NESs (from 1 to 10). Results show that combining NESs in parallel is an effective method to increase the excitation range over which a NES is effective.
2

The New Zealand National Environmental Standards for ambient air quality: analysis and modelling case study

Thornton, David Phillip January 2007 (has links)
Historically, the New Zealand rationale behind air quality management has been to adopt an effects-based approach based on environmental impacts. Generally, this method has been efficient in that it permitted emitters to decide how to minimise and mitigate impacts. However, to address the inconsistencies in air quality management across New Zealand born of this approach, and to permit measures designed to improve the working of the Resource Management Act (RMA), National Environmental Standards for Ambient Air Quality have been developed and implemented to establish consistent regulation and protection for all New Zealanders. The standards were gazetted in September 2004, for full implementation by 2013. This thesis explores the implementation of the National Environmental Standards for Ambient Air Quality, examining the philosophy behind the standards and associated strategies for dealing with air pollution management in New Zealand, and the international context for the development of appropriate tools to address air quality concerns. The research also provides an independent dispersion modelling assessment of the application of the Ministry for the Environment's initiative regarding sulphur dioxide in the Marsden Point airshed, Northland, utilising The Air Pollution Model (TAPM) for a period when heightened concentration values had been recorded. The key outcomes of the thesis are: (i) 99.9th percentile and maximum values for the simulated two-day modelling case study are within those stipulated by the air quality standards for sulphur dioxide; (ii) modelled concentrations associated with shipping within the airshed of interest contribute significantly to total modelled values; (iii) the chief obstruction to increased use of the prognostic modelling approach is that of the unsatisfactory availability and integrity of emission inventories; (iv) performing long-term high-resolution simulations with multiple point sources is prohibitive due to computational demands; (v) good quality monitoring will always be required; (vi) the standards have broad and far-reaching implications for resource managers, resource users and possibly the economy of individual regions and the country as a whole; (vii) the successful implementation of the National Environmental Standards for Ambient Air Quality in New Zealand will integrate a thorough understanding of modelling, measurements, meteorology and emissions.
3

Exploration of cargo spectrum and NES patterns recognized by the exportin CRM1

Kirli, Koray 29 October 2013 (has links)
No description available.
4

The New Zealand National Environmental Standards for ambient air quality: analysis and modelling case study

Thornton, David Phillip January 2007 (has links)
Historically, the New Zealand rationale behind air quality management has been to adopt an effects-based approach based on environmental impacts. Generally, this method has been efficient in that it permitted emitters to decide how to minimise and mitigate impacts. However, to address the inconsistencies in air quality management across New Zealand born of this approach, and to permit measures designed to improve the working of the Resource Management Act (RMA), National Environmental Standards for Ambient Air Quality have been developed and implemented to establish consistent regulation and protection for all New Zealanders. The standards were gazetted in September 2004, for full implementation by 2013. This thesis explores the implementation of the National Environmental Standards for Ambient Air Quality, examining the philosophy behind the standards and associated strategies for dealing with air pollution management in New Zealand, and the international context for the development of appropriate tools to address air quality concerns. The research also provides an independent dispersion modelling assessment of the application of the Ministry for the Environment's initiative regarding sulphur dioxide in the Marsden Point airshed, Northland, utilising The Air Pollution Model (TAPM) for a period when heightened concentration values had been recorded. The key outcomes of the thesis are: (i) 99.9th percentile and maximum values for the simulated two-day modelling case study are within those stipulated by the air quality standards for sulphur dioxide; (ii) modelled concentrations associated with shipping within the airshed of interest contribute significantly to total modelled values; (iii) the chief obstruction to increased use of the prognostic modelling approach is that of the unsatisfactory availability and integrity of emission inventories; (iv) performing long-term high-resolution simulations with multiple point sources is prohibitive due to computational demands; (v) good quality monitoring will always be required; (vi) the standards have broad and far-reaching implications for resource managers, resource users and possibly the economy of individual regions and the country as a whole; (vii) the successful implementation of the National Environmental Standards for Ambient Air Quality in New Zealand will integrate a thorough understanding of modelling, measurements, meteorology and emissions.
5

Mechanism and Control of Nuclear-Cytoplasmic Translocation of the Transporter Regulator RS1 / Mechanismus und Kontrolle der Translokation der Transporterregulator RS1 zwischen Kern und Zytoplasma

Filatova, Alina January 2009 (has links) (PDF)
Das RS1 Protein (Gen RSC1A1) beteiligt sich an der Regulation des Na+-D-Glukose-kotransporters SGLT1 und einiger anderer Transporter. In subkonfluenten LLC-PK1 Zellen hemmt RS1 die Freisetzung von SGLT1 aus dem trans-Golgi-Netzwerk und die Transkription von SGLT1. Während es sich in konfluenten Zellen hauptsächlich im Zytoplasma befindet, ist RS1 in subkonfluenten Zellen im Kern und im Zytoplasma lokalisiert. In der vorliegenden Arbeit wurden Mechanismus und Regulation der konfluenzabhängigen Kernlokalisation von RS1 untersucht. Dabel konnte gezeigt werden, dass die von Konfluenz abhängige Kernlokalisation von RS1 durch den Zellzyklus reguliert wird. In RS1 aus Sus scrofa (pRS1) wurde eine Sequenz identifiziert („nuclear shuttling signal“, NS), die für die konfluenzabhängige Verteilung von RS1 verantwortlich ist und sowohl das Signal für die Kernlokalisation (NLS) als auch das Signal für den Export aus dem Kern (NES) beinhaltet. Die NLS und NES Signale von RS1 vermitteln die Translokation des Proteins in den Kern und aus dem Kern mit Hilfe von Importin β1 bzw. CRM1, wobei die Verteilung von RS1 zwischen Kern und Zytoplasma durch die Aktivität des Exportsystems bestimmt wird. Es wurde gezeigt, dass die benachbarte Proteinkinase C (PKC) Phosphorylierungsstelle an Serin 370 von pRS1 die NS-gesteuerte Kernlokalisierung kontrolliert und für die vom Zellzyklus abhängige Kernlokalisation notwendig ist. Aufgrund der Ergebnisse der ortsgerichteten Mutagenese, PKC-Aktivierungsexperimenten und Massenspektrometrie-Analyse des Phosphorylierungsmusters von RS1 wurde ein Modell vorgeschlagen, das die Regulation der Kernlokalisation des RS1 Proteins in LLC-PK1 Zellen beschreibt. Dem Modell zufolge wird RS1 in subkonfluenten Zellen stark in den Kern befördert, während der Export von RS1 aus dem Kern nicht stattfindet. Das führt zur Anreicherung von RS1 im Kern. Nach Konfluenz wird Serin 370 durch PKC phosphoryliert, was die Steigerung des RS1-Exports aus dem Kern begünstigt und die überwiegend zytoplasmatische Lokalisation des Proteins in konfluenten Zellen hervorruft. Die konfluenzabhängige Regulation der Lokalisation von RS1 kann die Expression von SGLT1 während der Regeneration von Enterozyten im Dünndarm und der Regeneration von Zellen der Nierentubuli nach hypoxämischem Stress kontrollieren. Außerdem deutet die Analyse der Genexpression in embryonalen Fibroblasten der RS-/- Mäuse deutet darauf hin, dass die transkriptionale Regulation durch RS1 im Zellzyklus und bei der Zellteilung eine wichtige Rolle spielen kann. Da die Lokalisation von RS1 zellzyklusabhängig ist, kann RS1 für die Regulation der Transporter in spezifischen Phasen des Zellzyklus wichtig sein. / The RS1 protein (gene RSC1A1) participates in regulation of Na+-D-glucose cotransporter SGLT1 and some other solute carriers. In subconfluent LLC-PK1 cells, RS1 inhibits release of SGLT1 from the trans-Golgi network and transcription of SGLT1. In subconfluent cells, RS1 is localized in the nucleus and the cytoplasm whereas confluent cells contain predominantly cytoplasmic RS1. In the present study, the mechanism and regulation of confluence-dependent nuclear location of RS1 was investigated. Confluence dependent nuclear location of RS1 was shown to be regulated by the cell cycle. A nuclear shuttling signal (NS) in pRS1 was identified that ensures confluence-dependent distribution of pRS1 and comprises nuclear localization signal (NLS) and nuclear export signal (NES). The NLS and NES of RS1 mediate translocation into and out of the nucleus via importin ß1 and CRM1, respectively, and the nuclear/cytoplasmic distribution of the RS1 protein is determined by the nuclear export activity. The adjacent protein kinase C (PKC) phosphorylation site at serine 370 of pRS1 was shown to control nuclear localization driven by NS and is necessary for the differential localization of RS1 in quiescent versus proliferating cells. Basing on the data of site-directed mutagenesis, PKC activation experiments and mass spectrometry analysis of RS1 phosphorylation, the following model of the regulation of RS1 nuclear location in LLC-PK1 cells was proposed. In subconfluent cells, RS1 is actively imported into the nucleus whereas nuclear export of RS1 is not active leading to accumulation of RS1 in the nucleus. After confluence, phosphorylation of serine 370 of pRS1 by PKC takes place leading to enhancement of RS1 nuclear export and predominantly cytoplasmic distribution of the protein in the confluent cells. The confluence-dependent regulation of RS1 localization may control SGLT1 expression during regeneration of enterocytes in small intestine and during regeneration of renal tubular cells after hypoxemic stress. Moreover, the gene expression profiling of mouse embryonic fibroblasts with RS1-/- genotype suggests that transcriptional regulation by RS1 might be important for the cell cycle and cell division. Since RS1 localization depends on the cell cycle, RS1 might play a role in the regulation of the solute carriers during specific phases of the cell cycle.
6

Is Ignorance Bliss? Attributions for Seizures and Consequences of those Attributions among Participants with Psychogenic Non-epileptic Seizures

January 2012 (has links)
abstract: Psychogenic non-epileptic seizures (PNES), is a conversion disorder thought to be linked to unresolved emotional distress. While some studies suggest that PNES patients do not attribute their somatic symptoms to severe psychological experiences (Stone, Binzer, & Sharpe, 2004; LaFrance & Barry, 2005), it is unclear what PNES patients do think causes their seizures, and the psychological consequences of those attributions. The aim of the present study was to investigate PNES patients' attributions for their seizures, and to determine how these attributions relate to stress and emotion regulation. It was hypothesized that participants who attribute their seizures to something (i.e., have an explanation for their seizures) will have lower perceived stress and less difficulty with emotion regulation than those who are unsure of the cause of their seizures. Twenty-four PNES participants completed a questionnaire assessing seizure diagnosis, characteristics of seizure impact, perceived stress, psychological symptoms, emotion regulation, attributions for seizures, and coping resources. Contrary to the hypothesis, having an explanation for seizures, rather than being “unsure” of seizure cause, was related to greater perceived stress. While it would seem that attributing unpredictable seizure events to a cause would lower perceived stress and emotion regulation difficulty, this study indicates that an attribution to an unknown cause may be more beneficial for the individual. / Dissertation/Thesis / M.S. Psychology 2012
7

Arpeggios i NES-musik : Skillnader i användning av arpeggios, och hur väl det hörs skillnad på dem. / Arpeggios in NES music : Differences in usage of arpeggios, and how well one can hear the differences between them.

Magnusson, Klas January 2018 (has links)
Detta examensarbete skapades med målet att undersöka skillnader i preferensen gällande arpeggios i NES- och Famicom-musik baserat på kultur. Bakgrundskapitlet tar upp tidigare forskning inom tangentiella ämnen, samt beskriver arpeggios och hur NES- och Famicom-konsolerna är uppbyggda. En kvantitativ metod utvecklas sedan, och problematiseras. Detta följs av en beskrivning av det förarbete som gjordes, och skapandet av de två artefakter som användes. En enkät genomfördes efter förarbetet, och resultatet av denna analyseras därefter i rapporten. Resultatet visar på att det finns vissa skillnader i preferens mellan svenska och japanska lyssnare. Denna slutsats, samt resterande delar av rapporten diskuteras sedan och till sist skrivs det om framtida arbete, så som att en plug-in möjligtvis skulle kunna skapas efter detta arbete har gjorts. Denna plugin skulle göra det lättare att få musik att låta mer europeisk eller japansk.
8

Pompage énergétique en acoustique par absorbeur dynamique non-linéaire hybride passif-actif / Energy pumping in acoustics with an hybrid passive-active nonlinear dynamic absorber

Bryk, Pierre-Yvon 20 March 2018 (has links)
Ce mémoire est consacré à l'étude d'un absorbeur dynamique non linéaire hybride passif-actif (ADNLH) pour la réduction du bruit en basses-fréquences. La partie passive de l'ADNLH est une membrane en latex à déformée non linéaire dont la face avant est couplée au champ acoustique que l'on souhaite réduire. Cette membrane se comporte comme un oscillateur non linéaire et fait partie de la famille des absorbeurs non linéaires connus sous le nom de Nonlinear Energy Sink (NES). La face arrière de la membrane est encoffrée et un dispositif de contrôle actif est inclus dans le volume d'encoffrement. Ce dispositif est conçu pour modifier la raideur linéaire et l'amortissement de la membrane. Des précédents travaux ont été réalisés uniquement sur la partie passive (la membrane) et ont permis de valider le principe de pompage énergétique dans le domaine acoustique. Cependant la membrane seule possède des limitations (notamment le seuil de déclenchement du pompage) qui restreignent les applications possibles. L'objectif de l'ADNLH est d'améliorer les performances du pompage énergétique acoustique en modifiant les propriétés linéaires de la membrane grâce à la boucle d'asservissement. Dans un premier temps une étude théorique et expérimentale est réalisée sur l'ADNLH. L'ADNLH est ensuite couplé à un tube résonant avec une excitation sinusoïdale et en bruit blanc. Il permet bien d'écrêter le premier pic de résonance du tube avec de meilleures performances que la version passive. Enfin l'ADNLH est installé dans une salle peu amortie. Il permet d'atténuer la première résonance acoustique de la salle dans le cas d'une excitation sinusoïdale. / This thesis is devoted to the study of a hybrid passive-active nonlinear dynamic absorber for the reduction of noise in low frequencies. The passive part of the ADNLH is a membrane in latex with a nonlinear deformation and its front face coupled to the acoustic field to be reduced. This membrane is acting as a nonlinear oscillator and is part of the family of absorbers known as Nonlinear Sink Energy (NES). The rear face is enclosed and a active device is included inside this enclosure. This device is designed in order to modify the linear stiffness and the damping of the membrane. Previous work has been done only on the passive part (the membrane) and has validated the principle of energy pumping for Acoustics. However the membrane has some limitations (like the threshold of energy pumping) that restrain the practical applications. The goal of the ADNLH is to improve the performance of the energy pumping by modifying the linear properties of the membrane with the help of the active device. In a first time an experimental and theoretical study of the ADNLH is done. Then the ADNLH is coupled to a tube of air thanks to an academic assembly under a sinusoidal excitation or broadband. It allows to cut the top off the first acoustic resonance of the tube with better performances than the membrane alone. At last the ADNLH is set inside a weakly damped room. The ADNLH allows to attenuate the first resonance of the room in the case of a sinusoidal excitation. One also shows that the control of the damping of the membrane is the key parameter for the performance of the ADNLH.
9

Contrôle passif non linéaire d’un profil aéroélastique, simulations et expérimentations / Nonlinear passive control of an aeroelastic airfoil, simulations and experimentations

Amar, Luc 19 May 2017 (has links)
L’objectif de cette thèse est de contrôler passivement une instabilité dynamique appliquée au flottement d’un profil aéroélastique à l’aide de différents types d’Amortisseurs à Masse Accordés (AMA). Un profil 2D appelé Section Typique est utilisé tout au long de l’étude. En première partie, une étude comparative de trois modèles mathématiques d’interaction fluide/structure appliqués à la Section Typique (Theodorsen, LUVLM et UVLM) met en valeur les forces et faiblesses de chacun. Le banc d’essai aéroélastique en soufflerie, utilisé par la suite, est présenté puis identifié avec et sans vent (GVT). En deuxième partie, les calculs des vitesses critiques de Divergence, d’Inversion des Gouvernes et de Flottement sont automatisés avec le modèle Theodorsen afin de réaliser une étude paramétrique du banc d’essai et mettre en lumière les variables de conception les plus influentes. L’analyse modale présente différentes bifurcations liées au changement soudain du mode instable. Ensuite, le même algorithme est utilisé afin d’analyser la suppression du flottement à l’aide de trois géométries d’AMAs linéaires. La dernière partie présente l’étude expérimentale et numérique d’un AMA non linéaire de type Nonlinear Energy Sink (NES). La singularité de cette configuration est d’utiliser le volet en tant qu’amortisseur et ainsi, ne pas ajouter de masse (FSI-VA). En soufflerie, six comportements non linéaires sous-critiques (en deçà de la vitesse de flottement dans la configuration linéaire) sont observés, identifiés et analysés : cinq Cycles Limites d’Oscillations (LCO) et un battement non linéaire chaotique. / The aim of this thesis is to passively control a dynamic instability applied to an aeroelastic profile’s flutter using different types of Tuned Mass Dampers (TMD). A 2D profile called Typical Section is used throughout the study. In the first part, a comparative study of three mathematical models of fluid-structure interaction applied to the Typical Section (Theodorsen, LUVLM and UVLM) highlights the strengths and weaknesses of each code. The aeroelastic test bench, used subsequently, is presented and identified with and without wind (Ground Vibration Test, GVT). In the second part, critical velocities computations (Divergence, Control Surface Reversal and flutter) are automated while using the Theodorsen model in order to carry out the test bench parametrical study to highlight most influential variables. The modal analysis presents different bifurcations linked to the sudden change of the unstable mode. The last part presents the experimental and numerical studies of a nonlinear TMD called Nonlinear Energy Sink (NES). The uniqueness of this configuration consists in recycling flap’s vibrations as a flutter damper and thus, get a zero added mass. A nonlinear restoring force can be achieved by a highly nonlinear mechanism. The nonlinear structural behavior is derived analyticaly and is in good agreement with experimental torsion tests. In the wind tunnel, six subcritical nonlinear behaviors (below the flutter velocity in the linear configuration case) are observed, identified and then analyzed : five Limit Cycle Oscillations (LCO) and a chaotic nonlinear beating.
10

Em busca de um olhar judaico: análise das séries fotográficas Histórias Bíblicas, de Adi Nes, Marcados, de Cláudia Andujar, e Crisálidas, de Madalena Schwartz / In search of a Jewish eye: analysis of the photographic series Histórias Bíblicas, by Adi Nes, Marcados, by Cláudia Andujar, and Crisálidas, by Madalena Schwartz

Feder, Leonardo 29 May 2013 (has links)
O objetivo desta pesquisa de Mestrado é dissertar sobre o olhar judaico que, por suposição, permeia as obras de três fotógrafos contemporâneos e avaliar se há tendências que apontem para a judeidade das fotografias. Os artistas estudados são o israelense Adi Nes e as brasileiras de origem húngara Cláudia Andujar e Madalena Schwartz, que, respectivamente, produziram as séries Histórias Bíblicas (2003-2006), Marcados (1981-1983) e Crisálidas (1973-1976) publicadas em 2007, 2009 e 2012. Adi Nes (1966-), ao encenar em estúdio situações contemporâneas de miséria em Tel Aviv com atores representando personagens bíblicos (Noé, Abraão, Isaque, Jacó, Elias, José, Rute, Caim, Abel e Davi), reatualizou as histórias da Bíblia Hebraica, como faz o Midrash (livro ou trecho de comentários rabínicos), e, talmudicamente, conectou significantes aparentemente díspares que sugerem muitos significados. Cláudia Andujar (1931-) relacionou a situação indígena à história judaica, ao retratar os índios Yanomami com uma placa numerada no pescoço (para identificar qual fora vacinado), o que remete aos números tatuados na pele dos prisioneiros que ingressavam nos campos de extermínio durante a Shoá, o que, em contrapartida, reforça a ameaça à sobrevivência dos índios quando os brancos invadem as suas terras. Madalena Schwartz (1921-1993) fotografou travestis e transformistas do teatro underground realizado pelo Dzi Croquettes, grupo que, ao transitar entre os gêneros masculino e feminino, cultivavam identidades híbridas, fragmentadas e vivenciavam uma condição de exílio compartilhada pela artista, devido aos seus deslocamentos transculturais, ao fazer o percurso migratório Budapeste-Buenos Aires-São Paulo. / The aim of this research is to discourse about the Jewish eye that, by assumption, permeates the work of three contemporary photographers and evaluate if there are tendencies that point to the Jewishness of photographies. The studied artists are the Israeli Adi Nes and the Brazilians of Hungarian origin Cláudia Andujar e Madalena Schwartz, that, respectively, produced the series Biblical Stories (2003-2006), Marcados [Marked] (1981-1983) and Crisálidas [Chrysalides] (1973-1976) published in 2007, 2009 and 2012. Adi Nes (1966-), by staging in studio contemporary situations of misery in Tel Aviv with actors representing biblical characters (Noah, Abraham, Isaac, Jacob, Elijah, Joseph, Ruth, Cain, Abel and David), re-updated the stories of Hebrew Bible, as does Midrash (book or excerpt of rabbinic commentaries) and, talmudically, connected signifiers apparently different that suggest a lot of meanings. Cláudia Andujar (1931-) correlated the indigenous situation to Jewish history, by depicting the Indians Yanomami with a numbered plaque in neck (to identify who was vaccinated), what links to the numbers tattooed in the skin of prisoners that enter in death camps during Shoah, what, in return, reinforces the threat to survival of Indians when white people invade their lands. Madalena Schwartz (1921-1993) photographed travestites and crossdressers of underground theatre done by Dzi Croquettes, group that, by transiting between masculine and feminine genders, cultivated hibrid, fragmented identities and experienced an exilic condition shared by the artist, due to her transcultural moves, by doing the migratory route Budapest-Buenos Aires-São Paulo.

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