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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
231

Aproximações entre biologia, biopolítica e bioarte: um ensaio sobre a biocontemporaneidade / Approximations among biology, biopolitics and bioart: an essay on biocontemporaneity.

Luciana Valeria Nogueira 04 September 2009 (has links)
Este trabalho, de caráter ensaístico, pretende configurar algumas implicações do discurso biológico na contemporaneidade por meio da análise de como certos conceitos oriundos do campo das ciências biológicas espécie e gene, particularmente espraiam-se pelo corpo social, associando-se a determinados modos de subjetivação. A hipótese norteadora do estudo é a de que a não explicitação da fragilidade de ambos os conceitos obedece a demandas de controle e de assujeitamento, sobretudo no que se refere ao desenvolvimento e à utilização de biotecnologias. Trata-se da produção de novas formas de vida e, ao mesmo tempo, de processos específicos de subjetivação. Partindo da premissa de que um novo homem está sendo forjado pelas biotecnologias, argumenta-se no sentido de que elas puderam granjear certa legitimidade no imaginário social justamente porque tais conceitos são solidários à conversão da identidade biológica em bioidentidade. De acordo com Foucault, se antes as disciplinas se dirigiam ao homem-corpo, com a biopolítica elas se voltam ao homem-espécie. Os mecanismos regulamentadores da vida passam a fazer parte das relações de poder-saber, com vistas à manipulação dos fenômenos vitais. Assim, parece despontar claramente uma conexão direta entre o espectro biopolítico e os conceitos de espécie e de gene. Entende-se, pois, que os desdobramentos dessa conexão desembocarão no âmbito da biossociabilidade e da bioidentidade. Tomando como material empírico algumas obras do cinema e das artes plásticas, propõe-se uma visada analítica singular sobre as relações entre biologia, biopolítica e bioarte, tendo como perspectiva uma estética da existência baseada na ética da amizade. Na construção dessa visada, foi fundamental a filosofia produzida por Michel Foucault, bem como a de Gilles Deleuze e Félix Guattari. / This paper aims at reflecting on some implications around the contemporary biological discourse through the analysis of how some concepts in the field of biological sciences particularly species and genes spread through the social body, associating with certain modes of subjectivation. The guiding hypothesis of the present study is that the non-explicitation of the fragility of both concepts follows the demand for control and submission, especially as far as the development and usage of biotechnologies are concerned. Thus, there is at the same time production of new forms of life and production of specific processes of subjectivation. Considering the premise that a new man is being forged by the biotechnologies, it is argued that the latter have succeeded in gaining some legitimacy in the collective imaginary, especially because such concepts are solidary with the conversion of biological identity into bioidentity. According to Foucault, if the disciplines used to point toward the human-body, nowadays, under biopolitics they have moved into focusing on the human-species. The life-regulating mechanisms have become part of the power-knowledge relations focusing on the manipulation of vital phenomena. Thus, there seems to be a direct connection between the biopolitical spectrum and the concepts of species and genes. One can conclude, therefore, that the unfolding of this connection will lead into the scope of biosociablity and bioidentity. By taking some empirical work from the cinema and the plastic arts, this research proposes a singular analytical approach to the relations among biology, biopolitics and bioart, under a perspective which contemplates an esthetics of the existence based on the ethics of friendship. In the building of this approach, Michel Foucault\"s thought played a fundamental role, followed by Gilles Deleuze\'s and Félix Guattari\'s philosophies.
232

Liberdade e escolha : pressupostos éticos para a construção do individuo no existencialismo Sartriano

PEREIRA, José Alan da Silva January 2012 (has links)
Submitted by Caroline Falcao (caroline.rfalcao@ufpe.br) on 2017-06-07T18:46:22Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) 2012-dissertacao-JosePereira.pdf: 745659 bytes, checksum: 55a0a79509067f811c04c0dc82caac7c (MD5) / Made available in DSpace on 2017-06-07T18:46:22Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) 2012-dissertacao-JosePereira.pdf: 745659 bytes, checksum: 55a0a79509067f811c04c0dc82caac7c (MD5) Previous issue date: 2012 / A realidade humana enquanto existência, subjetividade e consciência representao ponto de partida da filosofia sartriana e encaminha-se para o cerne do debate existencialista traçado por ele e ilustrado pela liberdade. Nossa discussão parte dos princípios fundamentais do existencialismosartriano, da constituição da subjetividade econstrução da individualidade, por meio da colocação da fenomenologia específica da consciência ou do nada,até a ontologia da liberdade que fundamenta toda e qualquer construção e ação humana. Ao estabelecer essas bases, discutiremos a relação fundamental entre ser-em-si e ser-para-si apresentando uma compreensão diferenciada da consciência,elencando a intencionalidade como um dos conceitos fundamentais da ontologia fenomenológica de Sartre, bem comoum dos problemas básicos do existencialismo. Ao apresentarmos o homem a partirda dimensão de sua construção e liberdade deparamo-nos com uma problemática que, desde o seu nascedouro prometia desembocar com necessidade em uma discussão de fundo ético. Desse modo, a análise da filosofia de Sartre desenvolvida em O Ser e o Nada nos colocaram diante da possibilidade de uma ética. Ao discutir os conceitos de liberdade e escolha como sendo fundamentais a uma ontologia do humano, não podemos desviar o rosto da questão que colocava-se concomitantemente a esta, isto é, ao analisar os dramas da liberdade,a temporalidade, a angústia, a má-fé, a responsabilidade, enfim,a situação humana no mundo, o projeto que constitui e fundamenta a condição humana, o conjunto de tudo que constitui e indica o homem enquanto construtor de sua própria vida, deparamo-nos com a possibilidade de uma ética. Portanto, esse trabalho compromete-se em percorrer os principais conceitos sartrianos, para afirmar a possibilidade de uma ética nomeada antecipadamente por nós como uma ética da liberdade que assume as consequências de seus atos por sua responsabiliade intrínseca e inalienável. / The reality human being, subjectivity and consciousness the starting point of philosophy Sartre and refer to the existencial core of the debate outlined by him and illustrated by freedom. Thus, our discussion of the fundamental principles of Sartrean existencialism, the constitution of subjectivity, the construction od individuality, through the specific placement of the phenomenology of consciousness or anything, the ontology of freedom that underlies all constructions and human action. In establishing these bases, we discuss the fundamental relationship between being-in-itself and being-for-itself presenting a differentiated understanding of consciousness, intentionality uplifted as one of the fundamental concepts of Sartre’s phenomenological ontology, as well as one of the basic problems of existencialism. In presenting the man from the size of its construction and freedom we are faced with a problem that, since its birth promised in need culminate in a discussion of ethical fund. Thus, the analysis developed from philosophy of Sartre in Being and Nothingness put us at the possibility of an ethic. In discussing the concepts of freedom and choice as a fundamental ontology of the human face can not divert that question is this concurrently, that is, to analyze the drama of freedom, temporality, anxiety, poor faith, responsibility, and finally the human situation in the world, and is the project that underlies the human condition, everything is set and indicates the man as builder of his own life, we are faced with the possibility of an ethical. Therefore, this work undertakes to cover the main concepts sartrians, to affirm the possibility of an ethics appointed by us in advance as an ethics of freedom assuming the consequences of their by your sole risk inherent and inalienable.
233

Modos de coexistência mediada por uma ontologia da atenção distribuída digitalmente / Modes Of Mediated Coexistence: For An Ontology of Digitally Distributed Attention.

Andre Figueiredo Stangl 11 May 2016 (has links)
A pesquisa apresenta o conceito da coexistência mediada comunicacionalmente e tenta identificar os \"erros\" de percepção que podem ocorrer entre as diversas formas/ambientes de mediação comunicacionais, representadas pelos fluxos e refluxos: acústicos, visuais, elétricos e digitais. O conceito de coexistência mediada comunicacionalmente é inspirado na \"Investigação sobre os Modos de Existência\", de Bruno Latour, e opera uma tradução da tensão entre essencialismo e correlacionismo visando a um deslocamento da atenção que nos ajude a perceber etnograficamente as relações entre humanos e não humanos. Assim, na primeira etapa da pesquisa foi feita uma revisão da \"investigação\" de Latour, descrevendo seus passos até a missão diplomática e colaborativa de composição de um mundo comum, representada pela AIME. Em seguida, foram mapeados os principais usos do termo mediação, buscando identificar aqueles mais próximos da AIME, como foi o caso das explorações de Marshall McLuhan. Por fim, para identificar esses fluxos e refluxos ontológicos foi realizada uma experimentação etnográfica sobre o fenômeno dos rolezinhos, partindo a princípio dos rastros das controvérsias sobre o evento. O percurso que levou a pesquisa a formular o conceito de coexistência mediada também levou a propor uma estratégia de autoconhecimento, ou autoantropologia, como prefere Marilyn Strathern, que nos ajude a lidar com a multiplicação dos ambientes de nossas ecologias cognitivas. Tendo como base indícios de que a velocidade e a intensidade do trânsito entre as diversas mediações comunicacionais instauram desvios e confusões (semelhantes a \"erros\" de percepção, aqui nomeados como efeito Flammarion), a pesquisa então propõe/constata o seguinte: para aprender a conviver com os desafios de uma atenção distribuída digitalmente e no sentido da diplomacia que nos levará a compor um novo e múltiplo mundo, talvez seja necessário reaprendermos a nos livrar da atenção. / This research presents the concept of communicatively mediated coexistence, and it attempts to identify perceptions \"errors\" likely to occur among the several communicational mediation forms/environments represented by fluxes and refluxes: acoustic, visual, electric, and digital. The concept of communicatively mediated coexistence is inspired by Bruno Latour\'s \"An Inquiry Into Modes of Existence\" and it performs a translation of the tension between essentialism and correlationism, aiming at an attention shift that helps us to perceive, ethnographically, the relations between humans and non humans. Thus, the first stage of the research was a review of Latour\'s \"inquiry\", describing his steps up to the collaborative and diplomatic mission of composing a common world, represented by AIME. Next, the main uses of the term mediation were mapped in order to identify those closer to AIME, as in the case of Marshall McLuhan\'s explorations. Finally, in order to identify these ontological fluxes and refluxes, an ethnographic experiment about the phenomenon of rolezinhos (short strolls) was carried out, starting with the trail of controversies raised by the event. The path which led to the formulation of the concept of mediated coexistence, in this research, also led to proposing a strategy of self-awareness - or self-anthropology, as preferred by Marilyn Strathern - which may help us deal with the multiplication of the environments of our cognitive ecologies. Based on the evidence that the speed and intensity of the transit among several communicational mediations establish deviations and confusions (similar to perception \"errors\", here named as Flammarion effect), the research proposes/concludes the following: in order to learn to coexist with the challenges of a digitally distributed attention, and towards the diplomacy which will allow us to compose a new and multiple world, perhaps it is necessary to relearn to free ourselves from attention.
234

Projeto e existência: o vir-a-ser segundo a analítica existencial e a daseinsanálise / Projet et existence: la venue d'etre selon l'analyse existentielle et le daseinsanalyse

Birck, Luiz Henrique 24 August 2017 (has links)
Submitted by Marilene Donadel (marilene.donadel@unioeste.br) on 2017-11-30T20:13:28Z No. of bitstreams: 1 Luiz_H_Birck_2017.pdf: 1138264 bytes, checksum: 2e9a94d9c69229aad048382c4a2e0bc1 (MD5) / Made available in DSpace on 2017-11-30T20:13:28Z (GMT). No. of bitstreams: 1 Luiz_H_Birck_2017.pdf: 1138264 bytes, checksum: 2e9a94d9c69229aad048382c4a2e0bc1 (MD5) Previous issue date: 2017-08-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / La présente recherche combine dans son thème les éléments déjà déclarés dans son titre: «Projet et existence: la venue d'être selon l'analyse existentielle et le Daseinsanalyse». Avec ce thème, et avec le titre qui l'exprime, nous nous proposons d'étudier l'existence humaine et comment la philosophie phénoménologique de Martin Heidegger nous permet de penser un tel «objet de recherche». Nous montrons dans une trajectoire historique quelques concepts de la tradition philosophique afin d'indiquer des contextes que la phénoménologie tend à combattre, afin de contempler le mode de recherche de la phénoménologie. Nous présentons comment, dans l'analyse existentielle, nous pouvons comprendre les concepts qui nous permettent d'envisager une nouvelle compréhension de l'existant dans son futur devenir, ainsi que cette pensée a ouvert les portes aux discussions en Daseinsanalyse qui indiquait un horizon thématique avec intention de comprendre comment une psychologie de l'existence singulière peut comprendre l'existence humaine. La méthodologie choisie dans cette recherche était la phénoménologique (Heideggerian), qui nous a permis une attitude herméneutique contre les contextes nécessaires pour comprendre les phénomènes de l'existence. Cette recherche nous a conduit à comprendre comment, dans l'analyse existentielle, nous montrons une nouvelle compréhension de l'existant à partir de la dynamique existentielle de l'être-là, et comment cette proposition donne l'occasion de penser une Daseinsanalyse comme une psychologie. / A presente pesquisa conjuga em seu tema os elementos declarados já em seu título: “Projeto e existência: o vir-a-ser segundo a analítica existencial e a Daseinsanálise”. Com esse tema, e com o título que o expressa, nos propusemos a investigar a existência humana e como a filosofia fenomenológica de Martin Heidegger nos possibilita pensar tal “objeto de pesquisa”. Evidenciamos em uma trajetória histórica alguns conceitos na tradição filosófica afim de indicar contextos os quais a fenomenologia tende a combater, para assim contemplar o modo de investigação da fenomenologia. Apresentamos de que forma, na analítica existencial, podemos compreender os conceitos que nos possibilitam olhar para uma nova compreensão do existir em seu movimento de vir-a-ser, bem como de que forma este pensamento abriu portas para as discussões em Daseinsanálise na qual indicamos um horizonte temático com a intenção de compreender como uma psicologia da existência singular pode compreender o existir humano. A metodologia escolhida nesta pesquisa foi a fenomenológica (heideggeriana), a qual nos permitiu uma atitude hermenêutica frente aos contextos necessários para compreender os fenômenos do existir. Esta pesquisa nos levou a compreender como na analítica existencial evidenciamos um novo compreender a respeito do existir a partir da dinâmica existencial do ser-aí, e como esta proposta dá aberturas para se pensar em uma Daseinsanálise como uma psicologia.
235

As cifras da transcendência na filosofia de Karl Jaspers

Melo, Fernanda de Araújo 18 August 2009 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-10-10T11:41:04Z No. of bitstreams: 1 fernandadearaujomelo.pdf: 286912 bytes, checksum: 50abf19e6ffc68b1a525f40d5fc94deb (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-10-11T15:50:36Z (GMT) No. of bitstreams: 1 fernandadearaujomelo.pdf: 286912 bytes, checksum: 50abf19e6ffc68b1a525f40d5fc94deb (MD5) / Made available in DSpace on 2016-10-11T15:50:36Z (GMT). No. of bitstreams: 1 fernandadearaujomelo.pdf: 286912 bytes, checksum: 50abf19e6ffc68b1a525f40d5fc94deb (MD5) Previous issue date: 2009-08-18 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Esta pesquisa tem por objetivo principal obter uma compreensão das cifras da transcendência no pensamento de Karl Jaspers. Contudo, essa investigação mostra-se determinante para se pensar também em que medida a sua filosofia da existência poderia ser chamada de filosofia da transcendência. Pode-se dizer que a reflexão que o nosso autor estabelece em torno da existência humana possibilita a abertura para a transcendência no momento em que vincula a existência ao horizonte do fracasso e da sua conseqüente superação. Perceba que é no embate com essas situações-limite que se dá o ‘ocorrer’ da transcendência na forma de ‘sinais cifrados’. Isso evidencia, portanto, que o percurso estabelecido por Jaspers em sua fundamentação da especificidade da ‘condição humana’ culmina no âmbito da transcendência. Sob esta ocular, quer-se crer que esta pesquisa contribui, efetivamente, para se pensar como Jaspers estabelece a relação entre a existência e a transcendência, e, indo mais além, como se fundamenta o estatuto de sua filosofia da transcendência. / This thesis aims at understanding the “ciphers of transcendence” in Karl Jasper’s thought. We believe, however, that this investigation can be decisive to think how his philosophy of existence could also be called a philosophy of transcendence. We could say that the reflection that our author establishes around human existence makes possible an opening for transcendence when he connects existence to the horizon at failure and its consequent overcoming. One can observe it is in the confrontation with these extreme moments that transcendence occurs through “ciphered signs”. Therefore, that the way established by Jaspers in his grounding of the specific human condition ends up, in a decisive manner, in a sphere of transcendence. Under this aspect, we think this research contributes to understand how Jaspers establishes the connection between existence and transcendence and, furthermore, how he construes thes statute of his philosophy of transcendence.
236

Nationell naturvård i en lokal kontext : En analys av ett nationalparksförslag i Södra Jämtlandsfjällen

Lööf Ekström, Julia January 2014 (has links)
Local participation in nature conservation has gained more attention over the last decades due to international conventions as well as local and national initiatives. This development can be seen as a reaction to a more expert oriented nature conservation characterized by centralized control and strict preservation of so called "original" nature. The overall objective of this thesis is to contribute to research on new forms of conservation where democracy and local participation is included. The case study focuses on the process of producing a pre-study for a suggested national park in southern Jämtland in the Swedish mountain region, and aims to investigate to what extent local participation was included. The pre-study was led by the Swedish Environmental Protection Agency (SEPA) and the County Administrative Board (CAB) in Jämtland. The thesis is to some extent grounded in a political ecological perspective, which highlights connections between politics, societies and the environment. The methods used are semi-structured in-depth interviews and literature studies. The results show that although the stakeholders interviewed to some extent share views on the process, there are also differences. The SEPA and the CAB are generally satisfied with the result while there is some dissatisfaction among others. However, all stress that respect and dialogue are important and most actors see zoning and channeling within a potential park as part of a solution to past conflicts in the area. How the management structure will take form and to which extent it will include local participation has not been discussed in detail so far, although the Sámi demand to be included in any future management. These questions will be further investigated by the SPEA if they decide to proceed in a national park process. / Bortom konflikter: utmaningar och möjligheter i svenska fjäll
237

TOTALIDADE EXISTENCIAL E MUNDO COMO TOTALIDADE: O CONCEITO DE TOTALIDADE NA ONTOLOGIA FUNDAMENTAL DE MARTIN HEIDEGGER / EXISTENTIAL TOTALITY AND WORLD AS TOTALITY: THE CONCEPT OF TOTALITY IN MARTIN HEIDEGGER S FUNDAMENTAL ONTOLOGY

Flores, Juliana Mezzomo 26 March 2009 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The attendant work advances as a central goal the inquiry into Martin Heidegger s approach to the concept of totality. In this purpose we bound this interpretation within the period from 1927 to 1930, focusing on the works Being and Time, What is Metaphysics? and The Fundamental Concepts of Metaphysics: world, finitude and solitude. Starting with the reconstruction of the concept of totality in Being and Time, we seek to make clear the bearing of the theory about parts and wholes in the E. Husserl s 3º Logical Investigations. We shall argue that the influence of hursselian mereology takes place within two wide ranges of the heideggerian ontological inquiry: a) in the structuring of the analytic of being there and b) the problem formulation concerning the possible totality for human entity conceived as existence. Subsequently, this concept will be examined in writings such as The Fundamental Concepts of Metaphysics and What is Metaphysics?, having as focus the elucidation of the notion of being as a whole . Finally, we will approach the concept of totality in Being and Time and The Fundamental Concepts under a specific viewpoint: the problems linked to the concept of world in the works from 1927 and 1929. / O presente trabalho possui como objetivo central investigar a abordagem de Martin Heidegger ao conceito de totalidade. Para tanto, circunscreveremos nossa interpretação ao período de 1927 a 1930, concentrando-nos nas obras Ser e Tempo, Que é metafísica? e Os conceitos fundamentais da metafísica: mundo, finitude, solidão. Partiremos da reconstrução do uso do conceito de totalidade em Ser e Tempo, buscando evidenciar a presença da teoria sobre todos e partes apresentada na 3ª Investigação Lógica de E. Husserl. Argumentaremos que a influência da mereologia husserliana se dá em dois grandes âmbitos do questionamento ontológico heideggeriano: a) na estruturação da analítica do ser-aí e b) na formulação do problema acerca da totalidade possível para o ente humano concebido como existência. Posteriormente o conceito será examinado nos escritos Os conceitos fundamentais da metafísica: mundo, finitude e solidão e em Que é metafísica? , tendo como foco a elucidação da noção de ente na totalidade . Por fim, abordaremos o conceito de totalidade em Ser e Tempo e nos Conceitos Fundamentais sob um ponto de vista específico: os problemas vinculados ao conceito de mundo nas obras de 1927 e 1929.
238

Filosofická víra u Karla Jasperse / Philosophical faith in Karl Jaspers

Dostál, Václav January 2016 (has links)
Karl Jaspers is a thinker who tries in his philosophy to formulate a non-religious concept of faith. The thesis wants to clarify this "philosophical faith", which constitutes for Jaspers an answer to the question, "by what and toward what shall we live". Jaspers characterizes his philosophical faith as a "faith of a thinking man", which lay in grounds of philosophizing itself. On the one hand, philosophical faith (and philosophy itself) is different from the knowledge and science, because it cannot be reduced to a mere content; on the other hand, it is different from the religious faith and religion itself, mainly because it cannot accept the traditional Christian revelation. Finally, philo- sophical faith can be characterized as a communicative manner of life, which wants to reach the maximum possible level of understanding by all people. Keywords Karl Jaspers, philosophical faith, transcendence, existence, religion, revelation, communication
239

Phase structure and surface morphology effects on the optical properties of nanocrystalline PZT thin films

Puustinen, J. (Jarkko) 23 September 2014 (has links)
Abstract In this work, phase structure and the surface morphology effects on the optical properties of nonlinear active nanocrystalline PZT thin films, with the high refractive index (n ≈ 2.5), were studied. A preliminary thickness-temperature map of the majority phase was presented, showing the dependence of room temperature deposited films thickness and post-annealing temperature on the crystallization and surface morphology. Changes in structural phase and surface morphology were found to define the optical properties of the films. The optical absorption edge shifted to shorter wavelengths with decreasing film thickness and post-annealing temperature, which led to an increase in band gap energies with ΔEg ≈ 0.55eV. Structural phase evolution induced surface effects caused the definite diffuse elements in the transmission spectra of the films. Low and evenly distributed scattering amplitudes in k-space were seen for single-phase oriented films with non-textured surfaces and led to low diffuse transmission values with TD ≈ 5%. Confined and increased scattering amplitudes in k-space were seen for films with phase co-existence, leading to microstructure-induced textured surfaces and increased diffuse transmission values with TD ≈ 50%. Diffuse transmission properties of the films were also calculated from surface profile data, using scalar scattering theory. The results showed very good agreement with the experimentally defined values. The difference between modelled and measured values was 3.8% at the maximum. Also changes in the surface morphology and crystal orientation were found to modulate the full width at half maximum Δβ values of the TE0 optical mode, indicating a strong dependence on the surface scattering process. Sharp optical mode widths Δβ ≈ 0.0048 and Δβ ≈ 0.0006, for single-phase oriented and amorphous-like films, respectively, were found. / Tiivistelmä Tässä työssä tutkittiin nanokiteisten korkean taitekertoimen (n ≈ 2.5) omaavien PZT ohutkalvojen optisten ominaisuuksien riippuvuutta ohutkalvon faasirakenteesta ja pinnan morfologiasta. Rakenneanalyysien perusteella muodostettiin paksuus-lämpötila faasikartta havainnollistamaan jälkihehkutuslämpötilan ja kalvon paksuuden vaikutuksia huoneenlämpötilassa pulssilaserkasvatusmenetelmällä kasvatettujen ohutkalvojen faasirakenteen ja pinnan morfologian muokkautumiseen. Muutokset kalvon faasirakenteessa ja pinnan morfologiassa määrittivät täysin kalvon optiset ominaisuudet siten, että optinen absorptioreuna siirtyi alemmille aallonpituuksille kalvon paksuuden ja jälkihehkutuslämpötilan pienentyessä, aiheuttaen energiaraon kasvun (ΔEg ≈ 0.55 eV). Faasirakenteen indusoiman pinnan morfologian muokkautuminen määritteli myös ohutkalvon sirontaspektrin yksityiskohdat aaltolukuavaruudessa. Tasaisesti jakautunut pienen amplitudin omaava sirontaspektri ja alhainen diffuusi sironta (TD ≈ 5 %) oli ominaista yksifaasisille, voimakkaasti orientoituneille ohutkalvoille, kun taas alhaisille aaltolukuarvoille rajoittunut korkean amplitudin omaava sirontaspektri ja lisääntynyt diffuusi sironta (TD ≈ 50 %) oli ominaista kaksifaasisille ohutkalvoille. Tutkittujen ohutkalvojen sirontaspektrin diffuusi komponentti laskettiin myös käyttäen skalaaria sirontateoriaa. Ero laskettujen ja mitattujen arvojen välillä oli maksimissaan 3.8 %. Muutokset ohutkalvojen pinnan morfologiassa ja faasirakenteessa havaittiin myös moduloivan optisen TE0 moodin puoliarvoleveyttä. Alhaisimmat pouoliarvoleveydet havaittiin yksifaasisilla (Δβ ≈ 0.0048) ja amorfisenkaltaisilla ohutkalvoilla (Δβ ≈ 0.0006).
240

On some nonlinear partial differential equations for classical and quantum many body systems

Marahrens, Daniel January 2012 (has links)
This thesis deals with problems arising in the study of nonlinear partial differential equations arising from many-body problems. It is divided into two parts: The first part concerns the derivation of a nonlinear diffusion equation from a microscopic stochastic process. We give a new method to show that in the hydrodynamic limit, the particle densities of a one-dimensional zero range process on a periodic lattice converge to the solution of a nonlinear diffusion equation. This method allows for the first time an explicit uniform-in-time bound on the rate of convergence in the hydrodynamic limit. We also discuss how to extend this method to the multi-dimensional case. Furthermore we present an argument, which seems to be new in the context of hydrodynamic limits, how to deduce the convergence of the microscopic entropy and Fisher information towards the corresponding macroscopic quantities from the validity of the hydrodynamic limit and the initial convergence of the entropy. The second part deals with problems arising in the analysis of nonlinear Schrödinger equations of Gross-Pitaevskii type. First, we consider the Cauchy problem for (energy-subcritical) nonlinear Schrödinger equations with sub-quadratic external potentials and an additional angular momentum rotation term. This equation is a well-known model for superfluid quantum gases in rotating traps. We prove global existence (in the energy space) for defocusing nonlinearities without any restriction on the rotation frequency, generalizing earlier results given in the literature. Moreover, we find that the rotation term has a considerable influence in proving finite time blow-up in the focusing case. Finally, a mathematical framework for optimal bilinear control of nonlinear Schrödinger equations arising in the description of Bose-Einstein condensates is presented. The obtained results generalize earlier efforts found in the literature in several aspects. In particular, the cost induced by the physical work load over the control process is taken into account rather then often used L^2- or H^1-norms for the cost of the control action. We prove well-posedness of the problem and existence of an optimal control. In addition, the first order optimality system is rigorously derived. Also a numerical solution method is proposed, which is based on a Newton type iteration, and used to solve several coherent quantum control problems.

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