Дисертації: "Causal fields"

1

Johnston, Steven Paul. "Quantum fields on causal sets." Thesis, Imperial College London, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.526363.

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2

Sprickerhof, Jakob. "Causal structures in quantum field theory." Thesis, University of Leeds, 2015. http://etheses.whiterose.ac.uk/10658/.

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In this dissertation, I will argue that quantum field theory can be interpreted as a description of causal interactions. I will first discuss previous theories of physical causation, and come to the conclusion that they are inapplicable in quantum field theory. As a consequence, I will start to develop a new theory of causation by first analysing the concept ‘causation’ into the most basic and widely shared intuitions, in order to find out later whether these intuitions can be reduced to physics. I will then have a closer look on the intuition that causation is a directed relation, which is commonly regarded as incompatible with the symmetries of physics. I will present a new argument to the effect that causation and quantum field theory are compatible with respect to the directionality of causation. After that, I will analyse the theoretical description of interactions in quantum field theory, and in particular group structure, locality and local conservation laws will crystallise as the central concepts that a causal interpretation might be based on. Subsequently, I will discuss and present replies to what I believe are the most relevant objections to a causal interpretation of physics, namely, Haag’s theorem, the measurement problem and entanglement. In the final chapter of this dissertation, I will conjoin the results of the previous chapters to a new theory of causation for quantum field theory. The main result will be that a causal process is a quantum field theoretical interaction, i.e., the exchange of energy from an initial to a final state via a force.

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3

Tlas, Tamer. "A causal Spinfoam and new Group Field Theories." Thesis, University of Cambridge, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.612457.

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4

Dang, Nguyen Viet. "Renormalization of quantum field theory on curved space-times, a causal approach." Paris 7, 2013. http://www.theses.fr/2013PA077188.

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Le sujet de la thèse est la construction d'une théorie perturbative des champs quantiques en interaction sur un espace-temps courbe, suivant un point de vue conçu par Stueckelberg et Bogoliubov et developpé par Epstein-Glaser sur l'espace de Minkowski plat. En 2000 un progrès important fut réalisé par Brunetti et Fredenhagen qui réussirent à étendre la théorie d'Epstein-Glaser en exploitant le point de vue développé par Radzikowski pour definir les états quantiques sur un espace-temps courbe en terme d'ensembles de front d'onde. Ces résultats furent ultérieurement généralisés par Fredenhagen, Brunetti, Hollands, Wald, Rejzner, etc. Aux théories de Yang-Mills et de la gravitation. Cependant, même pour des théories sans invariance de jauge, de nombreux détails mathématiques sont restés inexplorés et parfois sans vérification. Dans cette thèse, on construit d'une façon totalement rigoureuse cette théorie dans le cas des champs sans invariance de jauge. Dans mon travail, j' ai revisité complètement cette théorie, résolvant au passage plusieurs questions laissées en suspens, incorporant de nombreux résultats nouveaux autour de ce programme et, le cas échéant, apportant des détails beaucoup plus précis sur les contre-termes dans le processus de renormalisation, une compréhension plus approfondie des ambiguïtés et une description géométrique des ensembles de front d'onde. L'ensemble de la thèse utilise un large éventail de techniques mathématiques : de la géométrie différentielle et pseudo riemannienne, des techniques d'analyse micro-locale et de géométrie symplectique pour les fronts d'onde, de l'analyse fonctionnelle, des résultats fins de la théorie des distributions
The subject of the thesis is the construction of a perturbative quantum theory of interacting fields on a curved space-time, following a point of view pioneered by Stueckelberg and Bogoliubov and developed by Epstein-Glaser on the flat Minkowski space-time. In 2000 a breakthrough was done by Brunetti and Fredenhagen who were able to extend the Epstein-Glaser theory by exploiting the point of view developed by Radzikowski to define quantum states on a curved space-time in terms of wave-front sets. These results were further extended by Fredenhagen, Brunetti, Hollands, Wald, Rejzner, etc. To Yang-Mills fields and the gravitation. However, even for theories without gauge invariance, many mathematical details were left unexplored and unquestioned. The task of Viet was precisely to derive fully rigorously this theory in the case there is no gauge invariance. In my work, I propose a complete review of the result, solving numerous questions, adding many new results around this program and, eventually, giving more precise details on the counterterms and ambiguities in the renormalization process, and a deeper understanding of the geometry of the wave front set of the n-point functions. All this thesis uses various mathematical techniques: differential and pseudo Riemannian geometry, microlocal analysis and the symplectic geometry of wavefront sets, functional analysis, fine results from the theory of distributions, Hopf algebras, etc

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5

Djapic, Lilijana. "Determination of residual stress fields caused by shot peening." Thesis, Imperial College London, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.338587.

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6

Ibnouhsein, Mohamed Issam. "Quantum correlations and causal structures." Thesis, Paris 11, 2014. http://www.theses.fr/2014PA112426/document.

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Les travaux récents en fondements de la théorie quantique (des champs) et en information quantique relativiste tentent de mieux comprendre les effets des contraintes de causalité imposées aux opérations physiques sur la structure des corrélations quantiques. Le premier chapitre de cette thèse est consacré à l'étude des implications conceptuelles de la non-localité quantique, notion qui englobe celle d'intrication dans un sens précis. Nous détaillons comment les récentes approches informationnelles tentent de saisir la structure des corrélations non-locales, ainsi que les questions que ces dernières soulèvent concernant la capacité d'un observateur localisé à isoler un système de son environnement. Le second chapitre détaille les effets de l'invariance de Poincaré sur la détection et la quantification de l'intrication. Cette invariance impose que tous les systèmes soient modélisés en dernière instance dans le cadre de la théorie des champs, ce qui implique qu'aucun système à énergie finie ne puisse être localisé, ainsi que la divergence de toute mesure d'intrication pour des observateurs localisés. Nous fournissons une solution à ces deux problèmes en démontrant l'équivalence générique qui existe entre une résolution spatiale finie des appareils de mesure et l'exclusion des degrés de liberté de haute énergie de la définition du système observé. Cette équivalence permet une interprétation épistémique du formalisme quantique standard décrivant les systèmes localisés non-relativistes et leurs corrélations, clarifiant ainsi l'origine des mesures finies d'intrication pour de tels systèmes. Le dernier chapitre explore un cadre théorique récemment introduit qui prédit l'existence de corrélations quantiques sans ordre causal défini. Procédant par analogie avec le cas des corrélations non-locales, nous présentons quelques principes informationnels contraignant la structure de ces corrélations dans le but de mieux en comprendre l'origine physique
Recent works in foundations of quantum (field) theory and relativistic quantum information try to better grasp the interplay between the structure of quantum correlations and the constraints imposed by causality on physical operations. Chapter 1 is dedicated to the study of the conceptual implications of quantum nonlocality, a concept that subsumes that of entanglement in a certain way. We detail the recent information-theoretic approaches to understanding the structure of nonlocal correlations, and the issues the latter raise concerning the ability of local observers to isolate a system from its environment. Chapter 2 reviews in what sense imposing Poincaré invariance affects entanglement detection and quantification procedures. This invariance ultimately forces a description of all quantum systems within the framework of quantum field theory, which leads to the impossibility of localized finite-energy states and to the divergence of all entanglement measures for local observers. We provide a solution to these two problems by showing that there exists a generic equivalence between a finite spatial resolution of the measurement apparatus and the exclusion of high-energy degrees of freedom from the definition of the observed system. This equivalence allows for an epistemic interpretation of the standard quantum formalism describing nonrelativistic localized systems and their correlations, hence a clarification of the origin of the finite measures of entanglement between such systems. Chapter 3 presents a recent theoretical framework that predicts the existence of correlations with indefinite causal order. In analogy to the information-theoretic approaches to nonlocal correlations, we introduce some principles that constrain the structure of such correlations, which is a first step toward a clear understanding of their physical origin

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7

OLIVERO, CARLOTTA. "Defining the causal association between human beta papillomavirus infection, keratinocyte stem cells expansion and skin cancer development." Doctoral thesis, Università del Piemonte Orientale, 2017. http://hdl.handle.net/11579/87003.

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I papillomavirus umani (HPV) sono piccoli virus nudi contenenti un genoma a doppia elica di DNA circolare di 8 kb che infettano gli epiteli squamosi stratificati cutanei e mucosali di differenti distretti corporei. Gli HPV possono stabilire infezioni latenti in individui sani, ma inducono anche lesioni neoplastiche benigne o maligne in base alle proprietà oncogene specifiche dei differenti genotipi. Fino ad oggi sono stati identificati più di 180 genotipi differenti di HPV che sono stati classificati in 5 generi sulla base dell’analisi filogenetica. Il genere Alpha (α-HPV) è il più caratterizzato e comprende i genotipi a tropismo mucosale associati all’ insorgenza di carcinoma a livello genitale (ad esempio HPV16 e 18). Gli HPV appartenenti al genere β (β-HPV) sono evoluzionisticamente distinti dal genere α e causano infezioni inapparenti o asintomatiche molto diffuse nella popolazione generale. Nei pazienti affetti da epidermodisplasia verruciforme (EV), una immunodeficienza primaria caratterizzata da un’alta suscettibilità all’infezione da β-HPV, questi virus replicano con alta efficienza, sviluppano il loro pieno potenziale trasformante, inducendo numerose lesioni simil verrucose con alto rischio di progressione a carcinoma cutaneo. Sebbene il loro coinvolgimento nel processo di carcinogenesi cutanea in pazienti immunocompetenti e immunosoppressi non-EV (con immunosoppressione primaria o acquisita) è ancora materia di dibattito, numerose evidenze epidemiologiche e sperimentali suggeriscono un ruolo carcinogenico di questi virus che inizia nelle fasi precoci e contribuisce alla patogenesi del carcinoma cutaneo. Il nostro gruppo ha dimostrato precedentemente la presenza di prodotti dei geni virali e l’amplificazione del genoma virale in lesioni cutanee precancerose derivate da pazienti trapiantati d’organo (OTR, Organ Transplant Recipient). Questi risultati rafforzano l’evidenza di un coinvolgimento dei β-HPVs nella patogenesi del carcinoma cutaneo. Sulla base dei dati già acquisiti, abbiamo studiato i meccanismi molecolari alla base dell’induzione del carcinoma cutaneo indotto da β-HPV in pazienti immunocompromessi attraverso differenti approcci, quali il modello di topo transgenico HPV8 e il saggio di tumorigenicita’ in vivo di tumori derivati da OTR. Pe capire il ruolo di β-HPV nello sviluppo del carcinoma cutaneo, è importante conoscere dove questo virus naturalmente si localizza. L’ipotesi attuale è che il reservoir di β-HPV risieda in cellule staminali con ciclo cellulare rallentato presenti nel follicolo pilifero (HF-KSC); tuttavia, la precisa popolazione di HF-KSC coinvolta nell’infezione latente di β-HPV è ancora sconosciuta. Per determinare il ruolo delle HF-KSC nel carcinoma cutaneo indotto da β-HPV, abbiamo utilizzato un modello di topo transgenico nel quale il promotore della cheratina 14 guida l’espressione della regione precoce di HPV8 (HPV8tg). I topi HPV8tg presentano uno spessore della cute piu’ ampio rispetto ai topi wild type e mostrano una cute iperproliferante. La proliferazione dei cheratinociti del follicolo pilifero è evidente nella popolazione di cellule staminali Lrig1+ (69 vs 55%, p<001, n=6), ma non lo è nelle popolazioni CD34+, LGR5+ e LGR6+. Questo è in linea con l’osservazione dell’espanzione dei cheratinociti Lrig1+ di 2,8 volte e dell’efficienza di formare colonie di 3.8 volte. In accordo con questi risultati, abbiamo osservato l’espressione nucleare di p63 in questa popolazione, nell’infindibulum e nella cute interfollicolare fiancheggiante, associata a un cambiamento di espressione tra la forma TA di p63 in ΔNp63 nella cute dei topi HPV8tg. Le cheratosi dei pazienti EV e alcune cheratosi attiniche (AK) di pazienti non EV mostrano un istologia simile associata alla riattivazione di β-HPV e all’espressione nucleare di p63 nell’ infindibulum e nella cute perifollicolare. Questi dati suggeriscono che il campo di cancerizzazione indotto da β-HPV inizia dalla “junctional zone” e predispone al carcinoma cutaneo.. Inoltre abbiamo realizzato un modello umanizzato di xenotrapianto ortotopico utilizzando tumori cutanei derivati da OTR. Questa tecnica permette di aumentare la disponibilità dei tumori cutanei – che è una delle limitazioni nell’ambito della ricerca sui tumori cutanei-, analizzare in dettaglio i meccanismi molecolari coinvolti nella tumorigenesi e identificare l’infezione e l’espressione di β-HPV in queste lesioni. Inoltre, questa tecnica permette di studiare la progressione della malattia da una situazione pre-cancerosa a una cancerosa, ad esempio da AK a SCC come riportato in questa tesi, che non può essere studiato a livello umano per la naturale necessità di rimuovere la lesione prima dell’evoluzione maligna. In questo contesto, rimane da stabilire se l’immunosoppressione faciliti la carcinogenesi anche attraverso la riduzione dell’immunosorveglianza. Per verificare questa ipotesi e generare un modello murino che ricapitolasse gli eventi che si verificano nei pazienti trapiantati, abbiamo incrociato i topi transgenici HPV8 (background genetico FVB/N) con i topi deficienti per il gene RAG2 (background genetico C57BL/6), che non producono cellule B e T. I risultati ottenuti fino ad ora con la generazione F2 indicano che l’immunosoppressione facilita la carcinogenesi anche inibendo l’immunosorveglianza del tumore, come dimostrato dai dati ottenuti; infatti,il numero di tumori cutanei nella cute dei topi HPV8+:Rag2-/- e il loro grado di displasia è risultato significativamente maggiore rispetto ai topi HPV8+:Rag2+/+. Nell'insieme, i risultati ottenuti in questo studio contribuiscono a chiarire la storia naturale dell’infezione da β-HPV e rafforzano l’ipotesi di un ruolo di questi virus nello sviluppo del tumore cutaneo.

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8

Yoboue, Tchindji Houphouët Félix. "Le viol comme arme de guerre en Côte d'Ivoire (1999-2010) : champs de causalité entre brisures, savoirs contaminés et vérités en ruines. Le plain-chant des narrations ethnophotographiques et du hors texte de 13 survivantes du peuple guéré à DUEKOUÉ en contre-configuration." Electronic Thesis or Diss., Université de Lorraine, 2022. http://www.theses.fr/2022LORR0276.

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Les récits de treize survivantes de viols subis à Duékoué, ville carrefour située à l’ouest de la Côte d’Ivoire, lors du coup d'État manqué du 19 Septembre 2002 jusqu’à la crise postélectorale de 2010, constituent la matrice narrative de cette thèse. Ces 13 femmes sont des survivantes, avec la sidération, l’angoisse, le désespoir des survivantes. Où trouver encore du sens quand on a vécu ce qu’elles ont vécu et vivent encore dix ans après ? En effet, les survivantes continuent de vivre un enfer permanent, victimes de formes lentes de violence invisibles, une forme subtile d’assassinat social par la mise à l’écart brutale de la famille et de la communauté, par la forme à dominante patriarcale et occidentale d’une réparation irrespectueuse ; des conséquences collatérales peu ou pas documentées voire déniées. Cette thèse tente de proposer des réponses à trois questions essentielles. Comment faire avancer une recherche formellement plus complexe que d’autres, avec une réflexion sur les tensions de l‘histoire ivoirienne, les récits des survivantes, le récit du chercheur-baoulé-survivant et des propositions esthétiques pour l’écrire ? Comment écrire scientifiquement sur la vulnérabilité, la détresse et la souffrance et rester à distance ? Comment restituer le chant des acteurs-témoins dans l’expression d’origine, de ces « vies minuscules », avec la parole hachée, balbutiante, et le faire dialoguer avec la parole, vigoureuse et affirmée, d’un chercheur qui découvre en fait lors d’une journée particulière qu’il est en quête de sa propre parole, celle d’un survivant, enfouie dans une gangue cadenassée. Il fallait pouvoir rendre l’adhésion du chercheur baoulé à sa propre parole et dans sa foi en les capacités du langage à atteindre l’intouchable et l’invisible, un monde perdu, le passé lui-même. Il fallait tenter de multiplier les détours narratifs et les pistes formelles, et prendre le risque de rejeter certains codes universitaires narratifs pour rendre palpable, en transformant une matière difficilement maniable et hautement inflammable, cette violence vécue par les survivantes dont Michel Foucault dit : « que le plus dangereux dans la violence est sa rationalité ». C’est aussi pour cette raison, pour faire ressentir plus particulièrement les ondes lointaines de cette souffrance exprimée et la certitude que nous passons souvent à côté, que le choix des narrations photoethnographiques s’est imposé. Pour confronter chacun des lecteurs à sa propre relation à l’image et d’une manière plus subtile aux récits des survivantes. Ce qui amène ensuite à réfléchir sur l’énigme des apparences. « Lire ce qui n’a jamais été écrit ». Pour dire la violence dans sa vérité, seule une anthropologie de l’attention qui entrerait en résonance avec ce qu’Édouard Glissant nomme « les profonds », désignant ainsi « ce qu’il y a réellement, concrètement, en dessous de l’apparence », permet de ressusciter la dignité de vie des survivantes et rendre légitime l’écriture d’un chercheur engagé
The accounts of thirteen survivors of rapes suffered in Duékoué, a crossroads city located in the west of Côte d'Ivoire, during the failed coup d'état of September 19, 2002 until the postelectoral crisis of 2010, constitute the narrative matrix of this thesis. These 13 women are survivors, with the astonishment, the anguish, the despair of the survivors. Where can we still find meaning when we have lived what they have lived and are still living ten years later? Indeed, the survivors continue to live in a permanent hell, victims of slow forms of invisible violence, a subtle form of social assassination through the brutal exclusion from family and community, through the predominantly patriarchal and of a disrespectful reparation; collateral consequences little or not documented or even denied. This thesis tries to propose answers to three essential questions. How to advance a research that is formally more complex than others, with a reflection on the tensions of Ivorian history, the stories of the survivors, the story of the researcher-baoulé-survivor and aesthetic proposals for writing it? How to write scientifically about vulnerability, distress and suffering and stay at a distance? How to restore the song of the actor-witnesses in the original expression, of these "tiny lives", with the choppy, stammering speech, and make it dialogue with the vigorous and assertive speech of a researcher who actually discovers during a particular day that he is in search of his own word, that of a survivor, buried in a padlocked gangue. It was necessary to be able to render the adhesion of the baoulé researcher to his own word and in his faith in the capacities of language to reach the untouchable and the invisible, a lost world, the past itself. It was necessary to try to multiply the narrative detours and the formal tracks, and to take the risk of rejecting certain narrative university codes in order to make palpable, by transforming a material that is difficult to handle and highly flammable, this violence experienced by the survivors of whom Michel Foucault says: "that what is most dangerous in violence is its rationality”. It is also for this reason, to make the distant waves of this suffering expressed more particularly felt and the certainty that we often overlook, that the choice of photoethnographic narrations was imposed. To confront each of the readers with their own relationship to the image and, in a more subtle way, to the stories of the survivors. Which then leads us to reflect on the enigma of appearances. “Read what has never been written”. To see violence in its truth, only an anthropology of attention that would resonate with what Edouard Glissant calls "the deep", thus designating "what there is really, concretely, below the appearance », making it possible to resuscitate the dignity of life of the survivors and to legitimize the writing of a committed researcher

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9

Siegel, Thomas A. "Magnetic fields of an underground coaxial cable caused by return currents in the earth." Ohio : Ohio University, 1989. http://www.ohiolink.edu/etd/view.cgi?ohiou1182517321.

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10

Watkins, Gavin Hughes. "Field and experimental investigations of ovine mastitis caused by Pasteurella Haemolytica." Thesis, Royal Veterinary College (University of London), 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.522804.

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11

Baloyi, Mafemani Phanuel. "Perceptions on the causes of poverty : field study at Mavambe Village." Thesis, University of Limpopo, Turfloop Campus, 2013. http://hdl.handle.net/10386/1101.

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Thesis (M.Dev.) -- University of Limpopo, 2013.
The purpose of this study was to understand the perceptions on the causes of poverty amongst the people at Mavambe village. The need for this study was relevant and necessary because most studies conducted on poverty were done on a general scale without taking into account the views of the rural people, such as traditional, community leaders and also local women. Consideration towards the rural areas is very minimal when it comes to fighting poverty. According to the Constitution of the Republic of South Africa, (1996), everyone has the right to have access to adequate housing, and the right to access health care services, including productive health care, sufficient food and water, social security. South Africa has had almost eighteen years of democracy; however most of those constitutional rights have not been adequately attained. Yet the Constitution suggests that those rights are guaranteed and that the state must take reasonable steps, to achieve the progressive realization of those rights. The study was qualitative in design. Purposive sampling was used to select the respondents in line with qualitative studies. In-depth interviews and focus group discussions were conducted with respondents The lack of houses, clean drinking water, adequate sanitation, and poor roads, in rural areas are major signs of poverty in rural areas. Because of lack of jobs and resources, majority people are in abject poverty. The study evaluated the scope and extent of poverty in the Mavambe village. The study further evaluated the perceptions of local, traditional and community leaders with regard to causes of poverty in the area. The study also solicited local people‟s perceptions and descriptions of poverty. The study highlights the multidimensionality of poverty. The study made the following key findings, there is lack of agricultural land and capital, the study recommends that every household should have little piece of land to grow crops and other productive uses and that those who want to do commercial farming should be assisted with capital. Another key finding is on income and social grant, the study recommends that the elderly and mothers who are not of school going age should be given social grant not school kids. The study also revealed that poor education system is a major cause of poverty and recommends that government must provide quality education, health, housing and sanitation. The study also revealed that there is lack of entrepreneurial development and thus recommends that entrepreneurial culture be natured as a viable option to deal with 6 issues of unemployment. The study also revealed that there is no infrastructure development in the rural areas and recommends that this should be given priority to change the economic set up of these areas. The study revealed that there is lack of values, respect and moral decay and recommends that families should cultivate and teach values to their children. The study concluded by providing recommendations on how poverty could be solved. These recommendations could also be of assistance for future policy development with regard to combating poverty.

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Vogelsang, Timo [Verfasser], Dirk [Gutachter] Sliwka, and Matthias [Gutachter] Heinz. "Management Practices and Employee Performance - Causal Evidence from Field- and Laboratory Experiments / Timo Vogelsang ; Gutachter: Dirk Sliwka, Matthias Heinz." Köln : Universitäts- und Stadtbibliothek Köln, 2020. http://d-nb.info/1213446139/34.

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13

Nishizawa, Shinichiro. "Induced current density in human body models caused by inhomogeneous magnetic fields of electrical appliances." Berlin Logos-Verl, 2005. http://deposit.ddb.de/cgi-bin/dokserv?id=2672479&prov=M&dok_var=1&dok_ext=htm.

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14

Klangboonrong, Yiarayong. "Modes of knowledge production : articulating coexistence in UK academic science." Thesis, Cranfield University, 2015. http://dspace.lib.cranfield.ac.uk/handle/1826/9618.

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The notion of Mode 2, as a shift from Mode 1 science-as-we-know-it, depicts science as practically relevant, socially distributed and democratic. Debates remain over the empirical substantiation of Mode 2. In particular, our understanding has been impeded by the mutually exclusive framing of Mode 1/Mode 2. Looking at how academic science is justified to diverse institutional interests – a situation associated with Mode 2 – it is asked, “What happens to Mode 1 where Mode 2 is in demand?” This study comprises two sequential phases. It combines interviews with 18 university spinout founders as micro-level Mode 2 exemplars, and macro-level policy narratives from 72 expert witnesses examined by select committees. An interpretive scheme (Greenwood and Hinings, 1988) is applied to capture the internal means-ends structure of each mode, where the end is to satisfy demand constituents, both in academia (Mode 1) and beyond (Mode 2). Results indicate Mode 1’s enduring influence even where non-academic demands are concerned, thus refuting that means and ends necessarily operate together as a stable mode. The causal ambiguity inherent in scientific advances necessitates (i) Mode 1 peer review as the only quality control regime systematically applicable ex ante, and (ii) Mode 1 means of knowledge production as essential for the health and diversity of the science base. Modifications to performance criteria are proposed to create a synergy between modes and justify public investment, especially in the absence of immediate outcomes. The study presents a framework of Mode1/Mode 2 coexistence that eases the problem with the either/or perception and renders Mode 2 more amenable to empirical research. It is crucial to note, though, that this is contingent on given vested interests. In this study, Mode 1’s fate is seen through academic scientists whose imperative is unique from those of other constituents, thereby potentially entailing further struggles and negotiation.

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15

Mavaleix-Marchessoux, Damien. "Modelling the fluid-structure coupling caused by a far-field underwater explosion." Electronic Thesis or Diss., Institut polytechnique de Paris, 2020. http://www.theses.fr/2020IPPAE012.

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Les sous-marins militaires doivent résister aux sollicitations induites par une explosion sous-marine. Pour s'en assurer, la simulation numérique est d'une importance capitale, compte tenu du coût très élevé des campagnes expérimentales. Une explosion sous-marine lointaine est un événement complexe qui a deux effets distincts : elle libère une onde de choc, puis crée une bulle de gaz oscillante qui pousse une grande quantité d'eau plus lentement. Les deux phénomènes ont des caractéristiques et des échelles de temps assez différentes. Dans ce travail, nous supposons que l'explosion est suffisamment éloignée pour (i) que la présence du navire affecte peu l'explosion, et (ii) permettre une séparation temporelle des deux phénomènes, tels que perçus par le navire. Dans ces conditions, notre objectif est de concevoir, implémenter (dans le cadre du calcul haute performance) puis valider une méthodologie de simulation numérique pour le problème d'interaction fluide-structure prenant en compte les deux phénomènes. Pour ce faire, nous commençons par étudier les deux perturbations en l'absence du sous-marin, pour déduire une modélisation et des méthodes numériques adaptées. Nous développons ensuite une procédure éléments de frontière (BEM) accélérée, basée sur une combinaison de la méthode de quadrature de convolution avec une approximation haute fréquence empirique originale. Plus largement, cette procédure permet de simuler efficacement des problèmes transitoires rapides 3D de propagation d'ondes en milieu non-borné, et offre une complexité très favorable : O(1) par rapport à la discrétisation temporelle et O(N log N) par rapport à la discrétisation spatiale. Enfin, nous mettons en place des stratégies performantes de couplage éléments finis/éléments de frontière (FEM/BEM) pour la phase d'interaction fluide-structure de l'onde de choc (acoustique linéaire) et celle de la bulle de gaz (écoulements incompressibles). La procédure globale, validée sur des problèmes académiques, fournit des résultats très prometteurs sur des cas industriels réalistes
Submarines must withstand the effects of rapid dynamic loads induced by underwater explosions. Due to the very high cost of experimental campaigns, numerical simulations are very important. A remote underwater explosion is a complex event that has two distinct effects: it sends a shock wave, then creates an oscillating gas bubble that sets water in slower motion. The two phenomena have quite different characteristics and time scales. In this work, we consider remote enough underwater explosions so that (i) the presence of the submarine only marginally affects the explosion, and (ii) there is a temporal separation of the two phenomena, as experienced by the ship. Under these conditions, our overall goal is to design, implement (in the context of high performance computing) then validate a computational methodology for the fluid-structure interaction problem, taking into account both phenomena. With this aim, we first study the two perturbations without considering the submarine, to propose appropriate modelling and numerical methods. Then, we design a fast boundary element (BEM) procedure, based on the combination of the convolution quadrature method and an original empirical high frequency approximation. The procedure allows to efficiently simulate 3D rapid transient wave propagation problems set in an unbounded domain, and shows advantageous complexity: O(1) in regards to the time discretisation and O(N log N) for the spatial discretisation. Finally, we implement adequate finite element/boundary element (FEM/BEM) coupling strategies for the shock wave fluid-structure interaction phase (linear acoustics) and that of the gas bubble (incompressible flow). The overall procedure, validated on academic problems, provides very promising results when applied on realistic industrial cases

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16

Kleiner, Johannes Verfasser], and Felix [Akademischer Betreuer] [Finster. "Dynamics of Causal Fermion Systems - Field Equations and Correction Terms for a New Unified Physical Theory / Johannes Kleiner ; Betreuer: Felix Finster." Regensburg : Universitätsbibliothek Regensburg, 2017. http://d-nb.info/1143948955/34.

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17

Oliver, Charlotte. "Phylogeny, histological observation, and in vitro fungicide screening and field trials of multiple Colletotrichum species, the causal agents of grape ripe rot." Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/99418.

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Colletotrichum acutatum and C. gloeosporioides are fungal plant pathogens that have a global distribution, extensive host range, and convoluted taxonomy. Both species can cause grape ripe rot and are considered endemic to Virginia US. In 2012, C. acutatum and C. gloeosporioides were reclassified into species complexes that consist of 31 and 22 accepted species, respectively. The objectives of this study were to: 1) survey Virginia vineyards for grape ripe rot, and morphologically and phylogenetically identify isolates to the species within the complexes, 2) conduct an in vitro fungicide assay to screen fifteen commercial fungicides and combinations of two fungicides for efficacy to control isolates from seven Colletotrichum species from Virginia vineyards, 3) sequence gene fragments from three subunits of the SDH enzyme in the fungicide-screened isolates to observe potential resistance mutations, 4) investigate the susceptibility of three grapevine tissues to Colletotrichum species, 5) observe potential infection structures before and after the application of fungicides, 6) evaluate the efficacy of commercial fungicide controls of grape ripe rot in the field, and determine the most advantageous timing of applications. In my studies, I identified six Colletotrichum species: C. aenigma, C. conoides, C. fioriniae, C. gloeosporioides, C. kahawae, and C. nymphaeae. I also found two additional groups; an isolate similar to C. limetticola and C. melonis and a group of isolates that are similar to C. alienum, C. fructicola, and C. nupharicola. I also identified captan, and mancozeb as two potential active ingredients for control of grape ripe rot isolates from Virginia via the in vitro fungicide assay. Additionally, I found that combinations of two active ingredients could increase the efficacy of benzovindiflupyr, copper, and polyoxin-D. C. fioriniae germination and production of melanized appressoria was documented on leaves. I observed appressorium formation with isolates of two C. fructicola-like genotypes and C. nymphaeae, as well as secondary conidiation with isolates of C. aenigma, C. fructicola-like genotype 3, and C. nymphaeae on blooms. And finally, benzovindiflupyr, cyprodinil + fludioxonil pre-mix, and potassium phosphite + tebuconazole were identified as candidates for chemical control for grape ripe rot in the field.
PHD

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18

Baris, A. N. Dalsu. "Suicide and other causes of death in electrical utility workers : their association with exposure to electric and magnetic fields." Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=28672.

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This dissertaion comprises three related papers.
The first paper reports a historical cohort mortality study which was carried out among 21,744 electrical utility workers in the province of Quebec. A total of 1582 deaths were observed at the end of follow-up (1970-1988). A job exposure matrix (JEM) was used to estimate the exposure to 60 Hz electric, magnetic, and pulsed electromagnetic fields (PEMF) from the code of the last job held by each worker. The results showed no evidence of excess of cause specific or general mortality relative to provincial death rates in the cohort overall. The ratios of Standardized Mortality Ratios (SMRs) as estimates of rate ratio (RR) in the exposed relative to the background group were also calculated. Statistically significant RRs were found for pancreatic cancer for electric fields (RR = 2.8, 95% Confidence intervals (CI) 1.13-7.01) and for lung cancer for PEMF (RR = 1.56, 95% CI 1.05-2.25). Deaths caused by accidents and violence showed significant RRs for electric fields (RR = 2.16, 95% CI 1.59-2.92), magnetic fields (RR = 1.76, 95% 1.29-2.39) and for PEMF (RR = 1.96, 95% CI, 1.40-2.71). Occupational accidents related to power lines explain for some of the excess of deaths from accidents and violence. There was a small non-significant association with magnetic fields for leukaemia (RR = 1.52, 95% CI 0.45-4.47) and brain cancer (RR = 1.59, 95% CI 0.57-4.31), but the results for these two sites were based on small numbers.
The second paper reports a case-cohort study to investigate a previously suggested association between exposure to electric and magnetic fields and suicide. Forty-nine deaths from suicide between 1970 and 1988 were identified in the above-mentioned cohort and a sub-cohort comprising a one percent random sample was selected from it. Cumulative and current exposures to electric fields, magnetic fields and PEMF were estimated for the sub-cohort and cases through the JEM. For cumulative exposure, rate ratios (RR) for all three fields showed mostly small non-significant increases in the medium and high exposure groups. The most elevated risk was found in the medium exposure group for electric field-geometric mean (RR = 2.76, 95% CI 1.15-6.62). The results did not differ after adjusting for socioeconomic status (SES), alcohol use, marital status and mental disorders. There was little evidence for an association of risk with exposure immediately prior to the suicide. Small sample size (deaths from suicide) and inability to control for all potential confounding factors were the main limitations of this study.
The third paper reports a study of validity attributing magnetic field exposure by using a worker's last job. This was done by comparing, in a sample of the cohort, estimates obtained using last job with those obtained using full work histories. The correlation between indices based on last job and those based on all jobs varied between 0.75 and 0.78. The study showed that the last job was particularly good in identifying the highest exposed individual. The results are most likely to be generalizable to other industries in which highest exposed jobs are also skilled jobs.

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Gauthier, Robert P. (Robert Paul) 1965. "An investigation of flow field perturbation caused by constant blade tip clearance in a turbine." Thesis, Massachusetts Institute of Technology, 1990. http://hdl.handle.net/1721.1/14150.

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20

Matta, Corrado. "A Field of Veiled Continuities : Studies in the Methodology and Theory of Educational Research." Doctoral thesis, Stockholms universitet, Institutionen för pedagogik och didaktik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-140475.

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Empirical educational research enjoys a methodological and theoretical debate that is characterized by a number of unresolved and lively debated controversies. This compilation thesis is an attempt to contribute to this debate using the toolbox of philosophy of science. The thesis consists of an introductory chapter and four essays. In the introductory chapter I identify three methodological and theoretical controversies that are discussed within the field of educational research. These are: 1) the controversy concerning the scientific status of educational research; 2) the controversy between cognitive and sociocultural theories of learning; and, 3) the controversy between realist and constructionist interpretations of theories of learning. I provide in the essays a critical assessment of the claims behind each of these controversies, and argue for an alternative reconstruction of these issues. In Essay I, I criticize a view about the interpretation of human action, labeled in the text as interpretivism. This view posits a sharp separation between the natural and social sciences, to the effect that the methods of the latter cannot be applied to the former. The first controversy seems to rest on this position. As I argue, the arguments in support of interpretivism are contradicted by actual research practice. I conclude that the interpretivistic claims lack support and that the general separation claim appears as problematic. A further debate has fueled the first controversy, that is, the supposed distinction between qualitative and quantitative methods. In Essay II, I argue against this distinction. More specifically, I discuss the concept of empirical support in the context of qualitative methods (for short, qualitative support). I provide arguments that although there are two specific and non-trivial properties of qualitative support, there is no methodological separation between quantitative and qualitative methods concerning empirical support. Considered together, the first two essays indicate two points of methodological continuity between educational research and other scientific practices (such as the natural sciences). I therefore conclude that the controversy concerning the scientific status of educational research rests in large part on unjustified claims. Essay III focuses on the second controversy. In this article I argue that Suárez’ inferential approach to the concept of scientific representation can be used as an account of scientific representation in learning, regardless of whether learning is understood as a cognitive or social phenomenon. The third controversy is discussed in Essay IV. Here, I discuss some ontological aspects of the framework of the actor-network theory. Reflecting on the use of this framework in the research field of Networked Learning, I argue that the assumption of an ontology of relations provides the solution for two puzzles about the ontology of networks. The relevance of my argument for the third controversy is that it suggests a point of connection between constructionist and realist interpretations of the ontology of learning. The last two essays suggest two points of continuities between theoretical frameworks that have been and still are argued to be incompatible.

At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 2: Manuscript.

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Sassen, Douglas Spencer. "Pseudokarst topography in a humid environment caused by contaminant-induced colloidal dispersion." Thesis, Texas A&M University, 2003. http://hdl.handle.net/1969.1/455.

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Over fifty small sinkholes (~1 meter in depth and width) were found in conjunction with structural damage to homes in an area south of Cleveland, TX. The local geology lacks carbonate and evaporite deposits associated with normal sinkhole development through dissolution. The morphology and distribution of sinkholes, and the geologic setting of the site are consistent with piping erosion. However, the site lacked the significant hydraulic gradient or exit points for sediment associated with traditional piping erosion. In areas of sinkholes, geophysical measurements of apparent electrical conductivity delineated anomalously high conductivity levels that are interpreted as a brine release from a nearby oil-field waste injection well. The contaminated areas have sodium adsorption ratios (SAR) as high as 19, compared to background levels of 3. Sodium has been shown to cause dispersion of soil colloids, allowing for sediment transport at very low velocities. Thus, subsurface erosion of dispersed sediment could be possible without significant hydraulic gradients. This hypothesis is backed by the observation of the depletion of colloidal particles within the E-horizon of sinkholes. However, there is a lack of precedence of waste brines initiating colloid dispersion. Also, sodium dispersion is not thought to be an important process in piping erosion in humid settings such as this one. Therefore, laboratory experiments on samples from the site area, designed to simulate field conditions, were conducted to measure dispersion verses pH, SAR and electrical conductivity (EC). Analysis of the experimental data with neural networks showed that an increase in SAR did increase dispersion. A dispersion prediction map, constructed with the trained neural network and calibrated geophysical data, showed correlation between sinkhole locations and increased predicted dispersion. This research indicates that a contaminant high in sodium content has caused colloidal dispersion, which may have allowed nontraditional subsurface erosion to occur in an area lacking a significant hydraulic gradient.

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Tröger, Sven, and Matthias Kröger. "Damage of bearings caused by electrical discharge currents at large drives derived from latest field research results." TU Bergakademie Freiberg, 2019. https://tubaf.qucosa.de/id/qucosa%3A38455.

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Bearing currents are not all the same. Under certain circumstances and special use cases classic bearing insulations are not sufficient anymore to prevent bearing currents due to the operation of frequency converters. Additional corrective measures have to be implemented to reduce the source of bearing currents the common mode current. The usage of nanocrystalline tape wound cores shows high effectiveness. As part of a big field study with more than 50 large drive trains in the primary industry, the damaging mechanics of bearing currents are examined under real conditions. Of exceptional high interest is the influence of disturbances which can hardly be simulated in the laboratory. Additional to the shielded motor cable parallel installed functional potential equalization cables applied multiple times have almost no effect in regard to reducing the bearing current. With an optimal installed functional potential equalization system more than 95 percent of the common mode current can flow back through the motor cable shield to the converter. The disturbance impact in the field can influence the voltage over the bearing that breakthroughs are favored but also reduced.

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Theint, Ei P. "Empirical Analysis of Causes of Income Inequality: A Level Playing Field for Children at the Start of School Career." Scholarship @ Claremont, 2014. http://scholarship.claremont.edu/scripps_theses/416.

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Numerous and countless factors have been theorized to be causes of inequality. This paper started with identifying the most important determinants of income inequality through theoretical research. Among the various theories of causes of inequality, I hypothesized creating a level playing for children at the very start of their career as students as an important determinant. In order to test the hypothesis that a level playing field is important to help fight inequality, a regression tailored for this question is created. I develop a regression model using the variable public expenditure on primary education as the variable to be tested while controlling for other important determinants of inequality including public expenditure per student on all stages of education, unemployment rate, GDP per capita, GDP growth, and governance indicator. The empirical model confirms theory that quality of primary education is highly beneficial for students. I conduct further theoretical research concerning ways to improve the quality of primary education and included them in policy recommendation section.

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Puig, Garcia Mireia. "Synthetic antifungal peptides for controlling brown spot of pear caused by Stemphylium vesicarium. Activity, mode of action and field evaluation." Doctoral thesis, Universitat de Girona, 2015. http://hdl.handle.net/10803/387564.

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Brown spot of pear is a fungal disease caused by Stemphylium vesicarium. Currently, the disease control efficacy is limited, due to the characteristics of disease and the reduction of the allowed fungicides. Therefore, this thesis is focused on finding new compounds to be applied alternatively or as a complement to the existing fungicides. Thus, twelve synthetic antifungal peptides selected from CECMEL11 library were evaluated in vitro against S. vesicarium. The most effective peptide was BP15 with a minimum inhibitory concentration (MIC) of 10 µM. Moreover, the peptide reduced significantly the disease severity in both ex vivo assays and under field conditions. The mechanisms of action of BP15 were studied. It was determined that the peptide permeabilizes the fungal cell membrane and it is internalized by the cells of germ tubes and hyphae of S. vesicarium.
L’estemfiliosi de la perera és una malaltia causada pel fong Stemphylium vesciarium. Actualment, els mètodes de control presenten una eficàcia limitada. Aquesta tesi es centra en millorar-ne el control mitjançant pèptids antimicrobians com a alternativa o suport als fungicides actuals. Dotze pèptids antimicrobians de la llibreria CECMEL11 van ser avaluats in vitro enfront el fong. El més eficaç va ser el péptid BP15 amb una concentració mínima inhibitòria (CMI) de 10 µM. Aquest pèptid es va mostrar eficaç en el control de la malaltia en assajos ex vivo i aplicat a camp, seguint el model de predicció BSPcast. En l’estudi dels mecanismes d’acció del BP15 es va determinar que el pèptid permeabilitza la membrana cel•lular del fong i que és internalitzat per les cèl•lules dels tubs germinatius i de les hifes de S. vesicarium.

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MASSA, LAURA. "Profili evolutivi del diritto degli appalti. Il paradigma delle cause di esclusione." Doctoral thesis, Università degli Studi di Cagliari, 2015. http://hdl.handle.net/11584/266834.

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Italian administrative law has been undergoing an evolution aimed at progressively eliminating the relevance that merely formal defects have traditionally held, an evolution which has nonetheless struggled to gain prominence in the case of the procedures for obtaining public commissions. In this regard, the aim of safeguarding the fundamental right to equality of treatment has been pursued by means of merely formal rules, whose strict compliance has always been regarded as indispensable for the accomplishment of the afore mentioned aim. The necessity of going beyond the former legal set-up in order to fully guarantee the principle of “favor partecipationis” has gained prominence with some difficulty and solely recently. This doctoral thesis, by analyzing the field of exclusions from public tenders, aims to illustrate how the evolution of national tender law has been taking place at the material level, and to show to what extent the phenomenon of the so-called hybridization of the Italian legal system under the influence of European law has actually affected this very evolution itself.

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Tvedt, Chryseis Theresa. "Efficacy of Seed Treatments and In-Furrow Fungicides for Management of Dry Bean Root Rot Caused by Rhizoctonia Solani and Fusarium Solani, and Field Pea Root Rot Caused by Fusarium Avenaceum and Fusarium Solani." Thesis, North Dakota State University, 2017. https://hdl.handle.net/10365/28366.

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Dry bean and field pea root rots have resulted in substantial yield losses in North Dakota. Root rot symptoms range from small lesions to complete root destruction. Traditional management practices such as seed treatment fungicides and crop rotation have proven insufficient under high disease pressure. The objective of this research was to determine the efficacy of in-furrow fungicide applications for management of dry bean and field pea root rot under field and greenhouse conditions. Fungicides were applied in-furrow at planting on dry beans and field peas. In most trials, the inoculated/non-treated control displayed significantly higher levels of root rot than the non-inoculated/non-treated control. In-furrow fungicides generally reduced root rot severity, sometimes significantly over the seed treatment; however, the level of control varied among hosts and pathogens. The results of these studies indicate that the use of in-furrow fungicides, along with cultural practices, may improve the overall management of root rot.

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Meloling, John H. "A caustic corrected uniform geometrical theory of diffraction for evaluating high-frequency electromagnetic fields near the cusp of the caustic caused by the curvature of an edge /." The Ohio State University, 1994. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487853913101801.

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Muhdi, Rani. "Re-Engineering the Operational System to Enhance the Customer Orientation of a Mid-Size Firm: A Field Study." [Johnson City, Tenn. : East Tennessee State University], 2002. http://etd-submit.etsu.edu/etd/theses/available/etd-0319102-195053/restricted/Muhdir041002a.PDF.

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Urs, Radu Dragos. "Non-parametric synthesis of volumetric textures from a 2D sample." Phd thesis, Université Sciences et Technologies - Bordeaux I, 2013. http://tel.archives-ouvertes.fr/tel-00821886.

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This thesis deals with the synthesis of anisotropic volumetric textures from a single 2D observation. We present variants of non parametric and multi-scale algorithms. Their main specificity lies in the fact that the 3D synthesis process relies on the sampling of a single 2D input sample, ensuring consistency in the different views of the 3D texture. Two types of approaches are investigated, both multi-scale and based on markovian hypothesis. The first category brings together a set of algorithms based on fixed-neighbourhood search, adapted from existing algorithms of texture synthesis from multiple 2D sources. The principle is that, starting from a random initialisation, the 3D texture is modified, voxel by voxel, in a deterministic manner, ensuring that the grey level local configurations on orthogonal slices containing the voxel are similar to configurations of the input image. The second category points out an original probabilistic approach which aims at reproducing in the textured volume the interactions between pixels learned in the input image. The learning is done by non-parametric Parzen windowing. Optimization is handled voxel by voxel by a deterministic ICM type algorithm. Several variants are proposed regarding the strategies used for the simultaneous handling of the orthogonal slices containing the voxel. These synthesis methods are first implemented on a set of structured textures of varied regularity and anisotropy. A comparative study and a sensitivity analysis are carried out, highlighting the strengths and the weaknesses of the different algorithms. Finally, they are applied to the simulation of volumetric textures of carbon composite materials, on nanometric scale snapshots obtained by transmission electron microscopy. The proposed experimental benchmark allows to evaluate quantitatively and objectively the performances of the different methods.

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Saha, Shrabani. "Causes of corruption : an empirical investigation in a cross-country framework : a thesis presented in fulfilment of the requirements for the degree of Doctor of Philosphy in Economics, Massey University, Turitea campus, Palmerston North, New Zealand." Massey University, 2009. http://hdl.handle.net/10179/1327.

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In recent years corruption has come to be considered as a pervasive phenomenon, and a major obstacle in the process of economic development. However, there exist few studies that discuss the factors that cause corruption and why some countries are more corrupt than others. This research contributes to that rather scanty literature and focuses on the causes of corruption. More importantly, the study empirically investigates various causes of corruption, in particular the role of economic development, democracy and economic freedom in explaining the observed variations in corruption across countries, and the nexus between democracy and economic freedom in combating corruption. The study first tests the reliability of the recent quantitative innovations in the study of corruption in terms of the Corruption Perception Index, constructed by Transparency International. Using theoretical and empirical analysis, various hypotheses regarding corruption and its determinants are examined using panel data for 100 countries during the period 1995 to 2004. The empirical findings show that the subjective indexing process of corruption perception eventually converges to a common consensus. In evaluating the relationship between economic development and corruption, the results suggest that income per capita, education, unemployment, income inequality, economic freedom and democracy are among the factors which determine and help explain the cross-country differences in corruption. Furthermore, the assessment of the relationship between democracy and corruption shows that an ‘electoral democracy’, represented by ‘political rights’, is not in itself sufficient to reduce corruption. Instead, for low levels of corruption to exist, the presence of an advanced fully-formed mature democracy is required. A characteristic of a mature democracy is the existence of an environment where the probability of being caught, if acting corruptly, is very high. In addition, the examination of the interaction between economic freedom and democracy suggests that economic freedom reduces corruption in any political environment, and the effect is substantially larger with a high level of democracy. The interesting and important findings of the analysis indicate that there exists a non-linear relationship between corruption and the level of income as well as democracy. The findings suggest that developed countries have succeeded in controlling corruption through higher levels of economic development along with the economic and political freedoms that their peoples enjoy.

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31

Khan, Khalid. "The violation of psychological contract : possible causes for the failure of organizational incentive systems to motivate knowledge sharing : a thesis presented in partial fulfilment of the requirements for the degree of Master of Management in Human Resource Management, Massey University, Palmerston North, New Zealand." Massey University, 2009. http://hdl.handle.net/10179/1223.

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Researchers and practitioners have linked the survivability of organization to their ability to manage their knowledge resource. This ability of the organizations depends on providing the technological support for the creation of knowledge, organizational structures (such as the organization reward systems) and the willingness of their employees to share their knowledge. Developments in information and communication technologies have facilitated organizations in developing the infrastructures that are required for the dissemination of knowledge. Organizations are thus left with the challenge of developing organizational structures that will motivate knowledge sharing among its employees. The knowledge sharing problem, which was once seen as an issue of capturing can codifying information, is now seen as a challenge of motivating individuals, the true owner of knowledge, to share their valuable resource. Behavioural scientists have taken interest in knowledge sharing as a form of helping behaviour which is directed at the organizations or member within the organizations. Although organizations have great desire that their managers engage in this behaviour, it is the discretion of their employees whether they want to share or withhold their knowledge. Organizational structural control mechanisms (such as the performance evaluation systems) have limited success in enforcing such behaviour as there are no means of measuring its outputs. Organizations depend on their incentive systems to motivate knowledge sharing. Research into motivation indicates that there is no easy fix to achieve this. Organizations have to balance the use extrinsic and intrinsic motivators, considering the specific motivational requirements of their employees. Motivational interventions, such as the use of incentives, are dependent on the level of trust the employees have in their managers and the organization in whole to deliver on those incentives in a fair and equitable manner. Where trust levels are not sufficient, employees tend to ignore such incentives and tend to further disinvest discretionary efforts. The current study used the psychological contract theory as a frame work for understanding the dynamics of the employee-employer exchange. The central premise of the theory is that employees tend to lose trust in the organization or the agent of the organization, when they perceive that their expectations have not been met. In addition to the lost of trust, psychological contract violation is also negatively associated with desirable organization behaviours and attitudes – such as commitment, in-role and extra-role effort – and is positively associated with undesirable organization behaviours and attitudes such as intention of turnover. The current study used a qualitative research design to investigate how the violation of the psychological contract can add to the ineffectiveness of the organization incentive system to motivate knowledge sharing. Using semistructured interviews the participants were provided with short scenarios (vignettes) which simulated occurrences of psychological contract violation. The participants, acting as informants, responded to question with regards to how the situations depicted in the vignettes would affect the vignette characters’ work behaviours, specifically their desire to share knowledge.

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CARDOSO, Alessandra Marques. "Surto de infecção após videoscopias causado por Mycobacterium massiliense em Goiânia-GO : análise molecular e determinação da suscetibilidade aos antimicrobianos." Universidade Federal de Goiás, 2009. http://repositorio.bc.ufg.br/tede/handle/tde/1590.

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Made available in DSpace on 2014-07-29T15:26:25Z (GMT). No. of bitstreams: 1 AlessandraMarques2009.pdf: 692808 bytes, checksum: 9a7b1bde8039039ba579f8e25c59ead5 (MD5) Previous issue date: 2009-12-03
In recent years the number of infections caused by microbacteria non-tuberculous mycobacteria (NTM) has increased mainly due to opportunistic infections in individuals imunocompormetidos and improvement of farming techniques and identification of MTN. Mycobacterium massilienese is an emerging body associated with wound infections, abscesses and pneumonia. An outbreak of infection after videoscopy occurred between 2005 and 2007 in seven hospitals in Goiânia-GO, in central Brazil. The objective of this study was to identify NTM isolated from patients with infection after arthroscopy and lararoscopia by PCR followed by analysis of fragment length polymorphism restrção (PRA-hsp65), compared by gel electrophoresis pulsed-field gel (PFGE), sequencing of the partial rpoB gene and determination of antimicrobial susceptibility in vitro. NTM were recovered from samples (exudate abscess subcutâneio) of 18 patients involved in the outbreak. In the period leading up to this study there was no reported case of infection after videoscopy caused by MTN in Goiania. The 18 isolates were identified as M, massiliene and genotyped as a single clone, indicating that they had a common origin, suggesting a common source of infection for the patients involved in the outbreak. The epidemic isolates were susceptible to amikacin (MIC90 4 micrograms / ml) and clarithromycin (MIC90 <1 ug / ml), but resistance to ciprofloxacin (MIC90 <128g/ml), tobramycin (MIC90 32 micrograms / ml) and intermediate susceptibility to cefoxitin (MIC90 64 ug / ml). In conclusion this study demonstrated the clonality of strains of M. massiliense involved in infections after procedures videoscopes and that they are susceptible to drugs indicated for the treatment
Durante os últimosd anos o número de infecções causadas por microbactérias não-tuberculosas (MNT) tem aumentado principalmente devido às infecções oportunistas em indivíduos imunocompormetidos e ao aprimoramento das técnicas de cultura e identificação das MTN. Mycobacterium massilienese é um organismo emergente, associado a infecções de feridas, formação de abscessos e pneumonias. Um surto de infecção após videoscopias ocorreu entre 2005 e 2007 em sete hospitais privados de Goiânia-GO, na região central do Brasil. O objetivo deste estudo foi identificar MNT isoladas de amostras de pacientes com infecção após artroscopia e lararoscopia por PCR seguida de análise de polimorfismo de fragmentos de restrção (PRA-hsp65), comparação por eletroforese em gel em campo pulsado (PFGE), sequenciamento parcial do gene rpoB e determinação da suscetibilidade antimicrobiana in vitro. MNT foram recuperadas das amostras (exsudato de abscesso subcutâneio) de 18 pacientes envolvidos no surto. No período antecedente a esse estudo não houve nenhum relato de caso de infecção após videoscopias causada por MTN em Goiânia. Os 18 isolados foram identificados como M, massiliene e genotipados como um único clone, indicando que tiveram uma origem em comum, o que sugere uma fonte comum de infecção para os pacientes envolvidos no surto. Os isolados epidêmicos apresentaram sensibilidade a amicacina (CIM90 4 ug/ml) e claritromicina (CIM90 < 1 ug/ml), porém resistência a ciprofloxacina (CIM90 < 128g/ml), tobramicina (CIM90 32 ug/ml), e sensibilidade intermediária a cefoxitina (CIM90 64 ug/ml). Em conclusão este estudo evidenciou a clonalidade de cepas de M. massiliense envolvidas em infecções após procedimentos de videoscopia e que as mesmas são suscetíveis às drogas indicadas para o tratamento

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33

Zhang, Mei. "Diagnostic de panne et analyse des causes profondes du système dynamique inversible." Thesis, Toulouse 3, 2017. http://www.theses.fr/2017TOU30260/document.

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Beaucoup de services vitaux de la vie quotidienne dépendent de systèmes d'ingénierie hautement complexes et interconnectés; Ces systèmes sont constitués d'un grand nombre de capteurs interconnectés, d'actionneurs et de composants du système. L'étude des systèmes interconnectés joue un rôle important dans l'étude de la fiabilité des systèmes dynamiques; car elle permet d'étudier les propriétés d'un système interconnecté en analysant ses sous-composants moins complexes. Le diagnostic des pannes est essentiel pour assurer des opérations sûres et fiables des systèmes de contrôle interconnectés. Dans toutes les situations, le système global et / ou chaque sous-système peuvent être analysés à différents niveaux pour déterminer la fiabilité du système global. Dans certains cas, il est important de déterminer les informations anormales des variables internes du sous-système local, car ce sont les causes qui contribuent au fonctionnement anormal du processus global. Cette thèse porte sur les défis de l'application de la théorie inverse du système et des techniques FDD basées sur des modèles pour traiter le problème articulaire du diagnostic des fautes et de l'analyse des causes racines (FD et RCA). Nous étudions ensuite le problème de l'inversibilité de la gauche, de l'observabilité et de la diagnosticabilité des fauts du système interconnecté, formant un algorithme FD et RCA multi-niveaux basé sur un modèle. Ce système de diagnostic permet aux composants individuels de surveiller la dynamique interne localement afin d'améliorer l'efficacité du système et de diagnostiquer des ressources de fautes potentielles pour localiser un dysfonctionnement lorsque les performances du système global se dégradent. Par conséquent, un moyen d'une combinaison d'intelligence locale avec une capacité de diagnostic plus avancée pour effectuer des fonctions FDD à différents niveaux du système est fourni. En conséquence, on peut s'attendre à une amélioration de la localisation des fauts et à de meilleurs moyens de maintenance prédictive. La nouvelle structure du système, ainsi que l'algorithme de diagnostic des fautes, met l'accent sur l'importance de la RCA de défaut des dispositifs de terrain, ainsi que sur l'influence de la dynamique interne locale sur la dynamique globale. Les contributions de cette thèse sont les suivantes: Tout d'abord, nous proposons une structure de système non linéaire interconnecté inversible qui garantit le fauts dans le sous-système de périphérique de terrain affecte la sortie mesurée du système global de manière unique et distincte. Une condition nécessaire et suffisante est développée pour assurer l'inversibilité du système interconnecté qui nécessite l'inversibilité de sous-systèmes individuels. Deuxièmement, un observateur interconnecté à deux niveaux est développé; Il se compose de deux estimateurs d'état, vise à fournir des estimations précises des états de chaque sous-système, ainsi que l'interconnexion inconnue. En outre, il fournira également une condition initiale pour le reconstructeur de données et le filtre de fauts local une fois que la procédure FD et RCA est déclenchée par tout fauts. D'une part, la mesure utilisée dans l'estimateur de l'ancien sous-système est supposée non accessible; La solution est de la remplacer par l'estimation fournie par l'estimateur de ce dernier sous-système
Many of the vital services of everyday life depend on highly complex and interconnected engineering systems; these systems consist of large number of interconnected sensors, actuators and system components. The study of interconnected systems plays a significant role in the study of reliability theory of dynamic systems, as it allows one to investigate the properties of an interconnected system by analyzing its less complicated subcomponents. Fault diagnosis is crucial in achieving safe and reliable operations of interconnected control systems. In all situations, the global system and/or each subsystem can be analyzed at different levels in investigating the reliability of the overall system; where different levels mean from system level down to the subcomponent level. In some cases, it is important to determine the abnormal information of the internal variables of local subsystem, in order to isolate the causes that contribute to the anomalous operation of the overall process. For example, if a certain fault appears in an actuator, the origin of that malfunction can have different causes: zero deviation, leakage, clogging etc. These origins can be represented as root cause of an actuator fault. This thesis concerns with the challenges of applying system inverse theory and model based FDD techniques to handle the joint problem of fault diagnosis & root cause analysis (FD & RCA) locally and performance monitoring globally. By considering actuator as individual dynamic subsystem connected with process dynamic subsystem in cascade, we propose an interconnected nonlinear system structure. We then investigate the problem of left invertibility, fault observability and fault diagnosability of the interconnected system, forming a novel model based multilevel FD & RCA algorithm. This diagnostic algorithm enables individual component to monitor internal dynamics locally to improve plant efficiency and diagnose potential fault resources to locate malfunction when operation performance of global system degrades. Hence, a means of acombination of local intelligence with a more advanceddiagnostic capability (combining fault monitoring anddiagnosis at both local and global levels) to performFDDfunctions on different levels of the plantis provided. As a result, improved fault localization and better predictive maintenance aids can be expected. The new system structure, together with the fault diagnosis algorithm, is the first to emphasize the importance of fault RCA of field devices, as well as the influences of local internal dynamics on the global dynamics. The developed model based multi-level FD & RCA algorithm is then a first effort to combine the strength of the system level model based fault diagnosis with the component level model based fault diagnosis. The contributions of this thesis include the following: Firstly, we propose a left invertible interconnected nonlinear system structure which guarantees that fault occurred in field device subsystem will affect the measured output of the global system uniquely and distinguishably. A necessary and sufficient condition is developed to ensure invertibility of the interconnected system which requires invertibility of individual subsystems. Second, a two level interconnected observer is developed which consists of two state estimators, aims at providing accurately estimates of states of each subsystem, as well as the unknown interconnection. In addition, it will also provide initial condition for the input reconstructor and local fault filter once FD & RCA procedure is triggered by any fault. Two underlyingissues are worth to be highlighted: for one hand, the measurement used in the estimator of the former subsystem is assumed not accessible; the solution is to replace it by the estimate provided by the estimator of the latter subsystem. In fact, this unknown output is the unknown interconnection of the interconnected system, and also the input of the latter subsystem

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34

Lane, Karl. "The feasibility of using remote sensing and field-based checks to monitor the impact caused by collection of wood in the Eastern Cape/Ciskei forest and thicket formations." Master's thesis, University of Cape Town, 1989. http://hdl.handle.net/11427/21929.

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Bibliography: pages 71-83.
A variety of studies have shown the problems of energy supply faced by low-income communities in southern Africa. Most of these communities are dependent upon indigenous fuelwood supplies. In addition, many of these communities use indigenous wood for construction. This largely uncontrolled utilisation imposes severe threats on woody vegetation communities. The Eastern Cape/Ciskei region is an area where energy supply problems are particularly severe and impacts on woody vegetation correspondingly severe. This study aimed to investigate the feasibility of using remote sensing techniques to monitor the the impact caused by collection of wood in the Eastern Cape/Ciskei forest and thicket communities. A variety of remote sensing techniques for landcover analysis were investigated. In all cases, visual interpretation was used because it is considerably cheaper and demands less technical expertise than would computer processing. In addition, many studies have shown visual interpretation to be superior. Maps were drawn from multitemporal aerial photograph sequences and from Landsat and SPOT satellite images. These maps showed that there has been relatively little change in area of woody vegetation in the study area since 1956. However, field studies showed that vegetation community structure had been degraded as a result of intense and sustained human impact. This qualitative decline also reflected a decline in usefulness of the woody vegetation of the area to local communities. This substantial degradation was not visible on any of the remote sensing imageries. This emphasises that field-based checks to monitor human impacts on forest and thicket formations are essential. Strategies for reducing the dependence of low-income communities on indigenous vegetation for energy supplies and constructional timber have been reviewed from the literature and these are descibed in Appendix 1. Most successful strategies in other parts of the world have been the result of a national commitment to tree planting, recognition of a multiplicity of constraints and the voluntary involvement of the communities the strategies are intended to assist.

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Mateus, Forero Andrea D. "DESIGN IN ADAPTATION TO DROUGHTS AND HEAT WAVES CAUSED BY CLIMATECHANGE IN RICE FARMS IN LERIDA, TOLIMA, COLOMBIA." Miami University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=miami151213167340772.

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36

Landwehrlen, Thomas. "Le déclin du Bayernpartei et ses déterminants causaux (1949-1969) : plaidoyer pour une analyse plurifactorielle et anti-retrospectiviste." Thesis, Lyon 2, 2011. http://www.theses.fr/2011LYO20114.

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Fondé à Munich en octobre 1946 suite à la réorganisation d’un proto-parti mariant rejet de l’unitarisme autoritaire et provincialisme anti-prussien, le Bayernpartei (BP) se fit après la guerre le courtier des revendications autonomistes bavaroises et le médiateur de l’hostilité populaire à l’égard des réfugiés allemands originaires d’Europe centrale et orientale. Couronné de succès lors des élections fédérales post-dictatoriales de 1949 – à l’occasion desquelles il recueillit 20,9% des voix en Bavière –, il présente la particularité d’avoir subi pendant vingt ans un déclin électoral régulier, et d’avoir totalement cessé d’être « relevant » au sens de Sartori au moment même où l’on assistait à l’échelle européenne, et même occidentale, à un nouvel essor des partis et formations régionalistes procédant du clivage centre/périphérie.Quels sont les déterminants causaux du progressif déclin du Bayernpartei ? Quels facteurs explicatifs apparaissent susceptibles de rendre compte de sa graduelle transformation en ce que Manfred Rowold estime être une simple association folklorique sans importance ? Tel est le questionnement sous-tendant le présent travail de thèse, et auquel l’auteur propose de répondre en se dégageant du rétrospectivisme monocausal, linéariste et exogénéisant dont firent preuve les (rares) politistes ayant tenté de rendre compte de l’étiolement politique passé du parti régionaliste bavarois
Founded in Munich in October 1946 after the reorganisation of a proto-party combining rejection of authoritarian unitarism and anti-Prussian provincialism, the Bavaria Party (Bayernpartei) appeared after the Second World War as the spreader of the Bavarian claims for autonomy, and as the echo box of popular hostility against German refugees from Central and Eastern Europe. After having been crowned with success at the German federal election of 1949 – on which it collected 20,9% of the votes in Bavaria –, he was affected during two decades by a steady electoral decline, so much so that it completely ceased to be “relevant” in the sense of Sartori at the very time when political scientists were witnessing at European (and even Western) level a new upsurge of regionalist parties and organisations.What are the causal determinants of the progressive decline of the Bavaria Party? What explanatory factors can be advanced to account for its gradual transformation into what Manfred Rowold considers to be a simple and irrelevant folk association? This is the question underlying the present work and to which the author proposes to respond by working on the assumption that it is necessary to break with the monocausal, linearist and exogenousing retrospectivism characterizing the analyses of the (rare) political scientists who have already attempted to explain the withering away of the Bavarian regionalist party

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37

Trucíos, Caciano Ramón [Verfasser], Christoph [Akademischer Betreuer] Kleinn, Christoph [Gutachter] Kleinn, and Rivas José Javier [Gutachter] Corral. "Quantifying the uncertainty caused by sampling, modeling, and field measurements in the estimation of AGB with information of the national forest inventory in Durango, Mexico / Ramón Trucíos Caciano ; Gutachter: Christoph Kleinn, José Javier Corral Rivas ; Betreuer: Christoph Kleinn." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2020. http://d-nb.info/121070272X/34.

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38

Erbas, Cihan. "Validation of remotely-sensed soil moisture observations for bare soil at 1.4 GHz a quantitative approach through radiative transfer models to characterize abrupt transitions caused by a ponding event in an agricultural field, modifications to the radiative transfer models, and a mobile ground-based system /." [Ames, Iowa : Iowa State University], 2009. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3371777.

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39

George, Aaron Geoffrey Lewis. "When Cowboys Come Home: Re-Imagining Manhood in Post-World War II America." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1491953123424439.

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40

Araneda, Bernardo Gabriel. "Simetrías ocultas, twistors, y estabilidad de campos lineales en agujeros negros." Doctoral thesis, 2018. http://hdl.handle.net/11086/6424.

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Tesis (Doctor en Física)--Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía, Física y Computación, 2018.
En el marco del problema de estabilidad de agujeros negros, esta tesis trata diversos aspectos de las ecuaciones de campos libres sin masa sobre espacio-tiempos curvos, con énfasis en espacios algebraicamente especiales que contienen agujeros negros como soluciones particulares. El enfoque central es el estudio de la posible correspondencia entre campos escalares y campos de spin superior, y de la existencia y origen de simetrías ocultas y ciertos mecanismos asociados a la teoría de twistors. Encontramos fórmulas explícitas de esta correspondencia, y mostramos que el patrón de simetrías subyacente se entiende desde el punto de vista de la covariancia conforme y la existencia de estructuras complejas en el espacio-tiempo. Analizamos también aspectos de estabilidad de los campos en el caso de agujeros negros estáticos asintóticamente anti-de Sitter. Estudiamos espacio-tiempos tanto de cuatro como de altas dimensiones.
In the context of the black hole stability problem, this thesis deals with several aspects of the massless free field equations on curved spacetimes, with emphasis on algebraically special spaces that contain black hole solutions as particular cases. The main approach is the study of the possible correspondence between scalar fields and higher spin fields, and of the existence and origin of hidden symmetries and certain mechanisms associated to twistor theory. We find explicit formulas for this correspondence, and we show that the underlying symmetry pattern is understood from the point of view of conformal covariance and the existence of complex structures on the spacetime. We also analyze aspects of the stability of the fields in the case of asymptotically anti-de Sitter static black holes. We study spacetimes of both four and higher dimensions.

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41

Banerjee, Shrabastee. "Empirical stadies of online markets: the impact of product page cues on consumer decisions." Thesis, 2021. https://hdl.handle.net/2144/42547.

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The widespread expansion of online markets in the past decade poses several questions for platforms, firms and customers alike. An important dimension to be explored in this domain is the provision of information on e-commerce platforms - given the increasing ease with which product pages can be customized to include a vast variety of content, how do these pieces of information interact? Further, what are the specific channels through which this information eventually influences consumer decision-making? My dissertation is situated in this space, and aims to look at how consumers respond to various “cues” that are being introduced by e-commerce platforms which offer products or services that can be purchased online, and how these cues might eventually influence decision-making. In my first dissertation project, the cue I focus on is user generated content. More specifically, I study how the introduction of the Q&A technology (which enables customers to ask product-specific questions before purchase, and receive answers either from other customers or the platform itself) affects the more widely established reviews and ratings feature on e-commerce platforms. I find that the addition of Q&As leads to better matches between customers and products, higher customer satisfaction, and resultantly higher ratings. My second project examines another cue that is common in online markets, which is the advertised reference price. My goal in this project is to examine how users react to a specific variant of such prices, namely the “Starting from...” price, using data from a large scale field experiment conducted on Holidu.com. My results indicate that raising “From” prices gives users a more accurate price estimate, but it negatively impacts outbound clicks and other engagement metrics. Taken together, the two projects aim to shed light on factors that influence consumer decision-making in an e-commerce setting, and the possible mechanisms underlying this influence.

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42

Görlich, Andrzej. "Causal dynamical triangulations in four dimensions." Praca doktorska, 2010. http://ruj.uj.edu.pl/xmlui/handle/item/38405.

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43

Dʹyachkov, Mikhail. "Longitudinal instabilities of bunched beams caused by short-range wake fields." Thesis, 1995. http://hdl.handle.net/2429/7226.

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This thesis investigates the effects of short-range wake fields on the collective longitudinal motion of charged particle bunches in circular accelerators, especially the onset of instability. At high intensity, a short-range wake field can distort the bunch potential well and thereby change the stationary distribution. It is shown that if this is not taken into account, instability thresholds will be incorrectly predicted. An integral equation derived from the linearized Vlasov equation is used to find the instability thresholds in the case of space-charge impedance alone for various distribution functions. The thresholds for instability caused by the coupling between the m = ±1 azimuthal modes have been obtained analytically for several common distributions. The criterion determining these thresholds appears to be the same as that for thresholds beyond which no stationary distribution can be found. A numerical method is also used to solve the linearized Vlasov equation for the self-consistent case, including distortion of the stationary distribution, and to find the thresholds. Physical explanations are provided for the eigenmodes and instability thresholds predicted by this method. This results in a much simpler stability criterion, which depends only on the stationary distribution and does not require solution of the linearized Vlasov equation. The behaviour of electron bunches beyond the instability threshold has also been studied using multiparticle tracking. Some interesting phenomena have been seen when the bunch length is smaller than that of the wake field. Under some conditions the bunch length oscillates in sawtooth fashion, i.e. slow relaxation is followed by fast blow-up. It has also been found that the bunch may split into two equal sub-bunches which oscillate around each other in binary star fashion. These effects may explain some recent observations in electron storage rings at SLAC and CERN.

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Santos, João Pereira dos. "Measuring causal impacts with natural and field experiments: evidence for firms, workers, consumers, and voters." Doctoral thesis, 2021. http://hdl.handle.net/10362/118704.

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This thesis explores an array of natural and eld experiments to produce causal estimates of the impact of interventions on four populations: firms, workers, consumers, and voters, making use of public and private micro-level data. The first chapter measures the effects on rm performance of a sharp increase in transportation costs on specific c highways. The second chapter investigates the labor market consequences of an exogenous shock, the unexpected in ow of repatriates following the independence of former Portuguese African colonies. The third chapter analyzes one of the fi rst soda taxes implemented worldwide that rises with sugar content to assess its effects on prices and consumption. The fourth chapter reports on a nationwide eld experiment assessing, for the first time, the capacity of the entire network of a country's ATM to "get out the vote".

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"Fully nonparametric efficient estimation for some causal inference problems and well-posedness on mean field theory." 2015. http://repository.lib.cuhk.edu.hk/en/item/cuhk-1291689.

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Zhang, Zheng.
Thesis Ph.D. Chinese University of Hong Kong 2015.
Includes bibliographical references (leaves 207-217).
Abstracts also in Chinese.
Title from PDF title page (viewed on 04, November, 2016).

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46

Chang, Che-Wei, and 張哲瑋. "A Flow Field Experimental Study on BCF Swimming of Bionic-Flexible Caudal Fin." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/99931972791476518912.

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碩士
國立臺灣大學
應用力學研究所
102
Abstract 　 In this study, we investigate three-dimensional thrust mechanisms of finite rigid and deformable flapping plates experiment as a caudal fin of the BCF (body and/or caudal fin) swimming fish at low Reynold numbers , water propeller vehicles in recent years, many scientist involved in research, and biomimetic water propeller vehicle is popular, with a high from its water propulsion mechanism, both environmental protection, green energy, privacy and so on. The experimental study of the fish BCF swimming field observation, which is characterized by the use of the vortex structure behind it generated vortex propulsion increases with high mobility and operability. Bionic flexible caudal fin is mainly carried out at low Reynolds number, in this case there will be many complex phenomena, such as: reversed-Karman vortex. To simplify the problem, this experiment aspect ratio 1 flapping, using particle imaging, and with the lift and drag measurements. Discuss the development of flexible fin behind and vortex structures. The working fluid is a mixture of experimental glycerol and water, with Reynolds number 500, the number (St=0.2,0.4 and 0.6), and two-way movement. Using the six-axis force compliance record up resistance over time and observe up under a different number St resistance changes with ansys simulation comparison of its results. Flow field observations, with the release of the developer particles to calculate the flow field vorticity with PIV method.

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Jhong, Yi-Lun, and 鍾依倫. "The Changes of Paddy Fields in Yuanli Township,Miaoli County and Their Causes." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/49519438108206258869.

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碩士
中國文化大學
地學研究所地理組碩士班
101
Rice is one of the world's major food crops, and has come through thousands years of evolution in cultivation, diffusion and evolution. The natural conditions in Taiwan are suitable for rice planting, and therefore sustain the crop on the island from coastal plains to the hills. From 1961 to 2010, however, Taiwan rice planting area down to remaining 31%; production was reduced to 58% of the original production. This trend indicates that Taiwan's the rice area and production are declining rapidly, but the decline rate is not equal, this phenomenon is caused by the motivation of this study to explore issues related to the rice space changes and influencing factors. This study takes research plots in Yuanli Township of Miaoli County. Yuanli is regarded as the " barn of Miaoli ". The paddy fields spans from the coast plains to the terrace terrain on the hills in Yuanli. Therefore, to study fluctuation factors of the different terrain area the rice area in the past 50 years, studies have shown to reduce the rice area is the transportation construction in the 1980s to impose agricultural land, change of agricultural land for other types of land use and urban planning, sub-to factor is the impact of agricultural policies ; unit increase in production, the benefit of improved the rice varieties and cultivation techniques; pressing issue at present is engaged in the rice population aging.

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LANTOVÁ, Petra. "Causes and consequences of personalities in microtine rodents." Doctoral thesis, 2011. http://www.nusl.cz/ntk/nusl-54437.

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This thesis focuses on individually specific differences in behavioural strategies, personalities, with two microtine rodents (Microtus arvalis and M. oeconomus) as study species. The work evaluates methodology necessary to reveal and measure consistent individual differences in behaviour, identifies possible proximate and ultimate mechanisms behind the existence of individual behavioural variability, and describes some ecological, evolutionary and behavioural consequences of personalities.

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Middleton-Hardie, Catherine. "A mutation in the gene encoding osteoprotegerin causes the severe bone disease Idiopathic Hyperphosphatasia." 2003. http://hdl.handle.net/2292/3173.

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Genetic analysis of a large family with Familial Idiopathic Hyperphosphatasia, a rare autosomal recessive bone disease, identified linkage to a region of chromosome 8q that contains the gene for osteoprotegerin (OPG), a key regulator of bone remodelling. Sequencing of this gene in members of the family identified an in-frame 3 base pair deletion resulting in the deletion of an aspartate residue at position 182, within the critical TNF-receptor-like region. Wild-type and mutant OPG cDNA were cloned into pcDNA3.1(-)/myc-His vector and expressed in HEK293 cells. Conditioned media samples containing the recombinant proteins were tested for their ability to inhibit bone resorption in a neonatal murine calvarial organ culture. Conditioned medium containing wild type OPG (wtOPG) inhibited bone resorption, whereas the conditioned medium containing the mutant protein (OPG∆D182) had no effect. Subsequently, the peptides were tested in a murine bone marrow osteoclastogenesis system. In this assay, OPG∆D182 had significantly lower activity than wtOPG. These results indicate the deletion of aspartate 182 impairs the ability of OPG to inhibit osteoclast formation and activation. The ability of wtOPG and OPG∆D182 to bind RANKL has been investigated using a rRANKL-GST pulldown system. These experiments demonstrated the OPG∆D182 had reduced ability to bind RANKL compared to wtOPG. A kinetic study using the surface plasmon resonance technology of BIAcore™ revealed the RANKL binding affinity of OPG∆D182 is lower than that of wtOPG. Altered processing of OPG∆D182 causes hyperglycosylation in comparison to wtOPG. Glycosylation was shown to be important for the function of full-length OPG, probably due to a requirement of glycosylation for correct folding. Site-directed mutagenesis identified two glycosylation sites that contribute to the hyperglycosylation of OPG∆D182. Glycosylation at one of these sites has potential structural implications by preventing disulphide bond formation and correct protein domain folding. The research highlights the effects of a single amino acid deletion on the structure and function of OPG. The deletion of aspartate 182 is a detrimental mutation that results in the severe phenotype seen in the patients, confirming the crucial role of OPG in normal bone physiology in humans.
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Boev, Ivan Krasimirov. "Radiated Electric and Magnetic Fields Caused by Lightning Return Strokes to the Toronto CN Tower." Thesis, 2010. http://hdl.handle.net/1807/24689.

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In the present PhD work, three sophisticated models based on the "Engineering" modeling approach have been utilized to conveniently describe and thoroughly analyze details of Lightning events at the CN Tower. Both the CN Tower and the Lightning Channel are represented by a number of connected in series Transmission Line sections in order to account for the variations in the shape of the tower and for plasma processes that take place within the Lightning Channel. A sum of two Heidler functions is used to describe the "uncontaminated" Return Stroke current, which is injected at the attachment point between the CN Tower and the Lightning Channel. Reflections and refractions at all points of mismatched impedances are considered until their contribution becomes less than 1% of the originally injected current wave. In the proposed models, the problem with the current discontinuity at the Lightning Channel front, commonly taken care of by introducing a "turn-on" term when computing radiation fields, is uniquely treated by introducing reflected and transmitted components. For the first time, variable speed of propagation of the Return Stroke current front has been considered and its influence upon the predicted current distributions along the whole Lightning Channel path and upon the radiated distant fields analyzed. Furthermore, as another novelty, computation of the electromagnetic field is accomplished in Cartesian Coordinates. This fact permits to relax the requirement on the verticality of the Lightning Channel, normally imposed in Cylindrical Coordinates. Therefore, it becomes possible to study without difficulty the influence of a slanted Lightning Channel upon the surrounding electromagnetic field. Since the proposed sophisticated Five-Section Model has the capability to represent very closely the structure of the CN Tower and to emulate faithfully the shape of, as well as physical processes within the Lightning Channel, it is believed to have the potential of truthfully reproducing observed fields. The developed modeling approach can be easily adapted to study the anticipated radiated fields at tall structures even before construction.

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