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Growing up with violent fathers: conversations with daughtersMtetwa, Thandazile Grace Nokukhanya 11 1900 (has links)
The effects of having witnessed their fathers’ violent behaviour impacts on daughters for a
long period afterwards, even in adulthood. This study explores this phenomenon by means of
literature review and interviews. The literature indicates that the effects of paternal violence is
linked to forced maturity, secrecy, pretending, self-blame, and negative impact on the
daughter’s relationships with both parents. A narrative approach was used to interview three
adult participants. The conversations were analysed using thematic analysis and hermeneutics.
Themes that emerged include avoidance, ambivalence towards the parents, aggression,
assertiveness, and over-responsibility. There is a tendency to avoid intense, emotionally-laden,
ambiguous and unpredictable situations through the use of interpersonal vigilance, an
emotionally strong poise, distancing, being agreeable and devoutness. Also, there is a fear of
becoming just like their abusive father. The psychological impact of being witness to a father’s
violent behaviours has long-lasting effects on daughters. / Psychology / M.A. (Clinical Psychology)
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A DESMUSICALIZAÇÃO DA MÍDIA EM TEMPOS DE HIPERMIDIATIZAÇÃO DA MÚSICA: o empobrecimento estético da música popular na programação televisiva brasileira / The unmusicalization of media in hyper mediatization of music time: aesthetic impoverishment of Brazilian popular music in television programimingSouza, Kleber Mazziero de 06 October 2014 (has links)
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Previous issue date: 2014-10-06 / The paper approaches the aesthetic-discursive impoverishment of massive popular song in Brazilian television media, comparing the historical-media-musical context of the 1960s and 1970s and the context of the first half of the second decade of this century. To delimit the discursive impoverishment was defined the concept of unmusicalization of television media. This work, of theoretical nature, aims to point out that the television media has a key role and important part of the responsibility for the impoverishment of discourse in the construction of Brazilian popular music. To do so, first, by analyzing poetic-aesthetic structural elements of musical and literary language of a popular song, was delimited the kind of structured musical work with poetic concern, that imparts an aesthetic standard of excellence. These songs were offered by the Television in the 60s and 70s, today no more. Afterwards, through research literature, documentary and empirical, describes analytical and interpretative way the historical period in which occurred the unmusicalization of television media. Finally, it is concluded that from the popularization of the Internet and the proliferation of various media that allow the access, storage, sharing musical repertoires and, above all, the listening on the move, the mass popular brazilian song, composed with concern poetic no more be longer present in Television and went on to appear in several other media. This broad presence of music in digital media was defined by the concept of hyper-mediatization of music, that would be a component of the unmusicalization of television media / O trabalho aborda o empobrecimento estético-discursivo da canção popular massiva exposta na mídia televisiva brasileira, na comparação entre o contexto histórico-midiático-musical das décadas de 1960 e 1970 e o contexto da primeira metade da segunda década do século XXI. Para definir tal empobrecimento discursivo encontrou-se o conceito de desmusicalização da mídia televisiva . O trabalho, de natureza teórica, tem como objetivo apontar que a mídia televisiva tem papel preponderante e parte importante da responsabilidade pelo empobrecimento na construção do discurso da música popular brasileira. Para tanto, primeiramente, por meio da análise poético-estética dos elementos estruturais das linguagens musical e literária de uma canção popular, delimitou-se a espécie de obra musical estruturada com acuro poético, que a ela empresta um padrão estético de excelência. Tais canções tinham espaços de veiculação nas grades de programação da mídia televisiva de outrora e nos dias atuais não mais os têm. Em seguida, por meio de pesquisas bibliográfica, documental e empírica, descreve-se de modo analítico-interpretativo o período histórico em que ocorreu essa desmusicalização da mídia. Por fim, constata-se que a partir da popularização da Internet e da proliferação de diversas mídias que permitem ao ouvinte o acesso, o armazenamento, o compartilhamento de repertórios musicais e, sobretudo, a audição em movimento, a canção popular massiva pautada pelo acuro poético deixou de estar presente na mídia televisiva e passou a figurar em outras diversas mídias. Essa ampla presença da Música nas mídias digitais definiu-se pelo conceito de hipermidiatização da música, que seria um dos componentes da desmusicalização da mídia televisiva.
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Linking tectonic evolution with fluid history in hyperextended rifted margins : examples from the fossil Alpine and Pyrenean rift systems, and the present-day Iberia rifted margin / Relation entre l'évolution tectonique et le rôle des fluides pendant la formation des marges de type rift : les exemples des Alpes, des Pyrénées et de la marge IbériquePinto, Victor Hugo 03 December 2014 (has links)
Cette thèse est centrée sur la caractérisation des traceurs des fluides qui interagissent avec les roches du socle et les roches sédimentaires dans les systèmes riftés hyper-amincis exposés dans la Téthys alpine, les Pyrénées et Ibérie-Terre Neuve. L’étude de ces fluides est basée sur les observations géologiques, les analyses géochimiques et les données géophysiques. Deux types de fluides ont été identifiés : les fluides associés à la croûte continentale, avec une signature caractérisée par Si et Ca, ainsi que les fluides liés au manteau en exhumation, avec une signature caractérisée par Si, Mg, Fe, Mn, Ca, Ni, Cr et V. La percolation des fluides est fortement liée à la formation des failles de détachement et à l’évolution des systèmes hyper-amincis. Le flux de fluides dans ces systèmes a des implications importantes pour les changements rhéologiques, pour la nature des sédiments et pour les modifications chimiques des réservoirs de la Terre. / This thesis focus in the identification of geochemical tracers and effects of fluid that interact with basement and sedimentary rocks in hyperextended systems. The investigation of such fluids is based on geological observation, geochemical analyses and geophysical data from fossil hyperextended rift systems exposed in the Alps and in the West Pyrenees, and the present-day distal margins of Iberia and Newfoundland. Two types of fluids were identified during this study. The first type, referred to as continental crust-related fluids, has a signature of Si and Ca. The second type, referred to as mantle-related fluids, has a signature of Si, Mg, Fe, Mn, Ca, Ni, Cr and V. The fluid percolation is strongly related to the formation of extensional detachment faults and the evolution of hyperextended systems. Fluid flow in these systems has major implications for the nature of sediments, rheological changes and chemical modifications of the Earth’s reservoirs throughout its evolution.
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Representação de conhecimento : programação em lógica e o modelo das hiperredes / Knowledge representation: logic programming and the hypernets modelPalazzo, Luiz Antonio Moro January 1991 (has links)
Apesar de sua inerente indecidibilidade e do problema da negação, extensões da lógica de primeira ordem tem se mostrado capazes de superar a questão da monotonicidade, vindo a constituir esquemas de representação de conhecimento de expressividade virtualmente universal. Resta entretanto solucionar ou pelo menos amenizar as conseqüências do problema do controle, que limitam o seu emprego a aplicações de pequeno a médio porte. Investigações nesse sentido [BOW 85] [MON 88] indicam que a chave para superar a explosão inferencial passa obrigatoriamente pela estruturação do conhecimento, de modo a permitir o exercício de algum controle sobre as possíveis derivações dele decorrentes. O modelo das hiperredes [GEO 85] parece atingir tal objetivo, dado o seu elevado potencial de estruturação e o instrumental que oferece para o tratamento de construções descritivas, operacionais e organizacionais. Além disso, a simplicidade e uniformidade sintática de suas entidades primitivas possibilita uma interpretação semântica bastante clara do modelo original, por exemplo, baseada em grafos. O presente trabalho representa uma tentativa de associar a programação em lógica ao formalismo das hiperredes, visando obter um novo modelo capaz de preservar as expressividade da primeira, beneficiando-se simultaneamente do potencial heurístico e estrutura do segundo. Inicialmente procura-se obter uma noção clara da natureza do conhecimento e de seus mecanismos com o objetivo de caracterizar o problema da representação de conhecimento. Diferentes esquemas correntemente empregados para esse fim (sistemas de produções, redes semânticas, sistemas de frames, programação em lógica e a linguagem Krypton) são estudados e caracterizados do ponto de vista de sua expressividade, potencial heurístico e conveniência notacional. A programação em lógica é objeto de um estudo em maior profundidade, sob os enfoques modelo-teorético e prova-teorético. Sistemas de programação em lógica - particularmente a linguagem Prolog e extensões em nível meta - são investigados como esquemas de representação de conhecimento, considerando seus aspectos sintáticos e semânticos e a sua retação com Sistemas Gerenciadores de Bases de Dados. O modelo das hiperredes é apresentado introduzindo-se, entre outros, os conceitos de hipernodo, hiperrelação e protótipo, assim como as propriedades particutares de tais entidades. A linguagem Hyper, para o tratamento de hiperredes, é formalmente especificada. Emprega-se a linguagem Prolog como formalismo para a representação de Bases de Conhecimento estruturadas segundo o modelo das hiperredes. Sob tal abordagem uma Base de Conhecimento é vista como um conjunto (possivelmente vazio) de objetos estruturados ou peças de conhecimento, que por sua vez são classificados como hipernodos, hiperrelações ou protótipos. Um mecanismo top-down para a produção de inferências em hiperredes é proposto, introduzindo-se os conceitos de aspecto e visão sobre hiperredes, os quais são tomados como objetos de primeira classe, no sentido de poderem ser valores atribuídos a variáveis. Estuda-se os requisitos que um Sistema Gerenciador de Bases de Conhecimento deve apresentar, do ponto de vista da aplicação, da engenharia de conhecimento e da implementação, para suportar efetivamente os conceitos e abstrações (classificação, generalização, associação e agregação) associadas ao modelo proposto. Com base nas conclusões assim obtidas, um Sistema Gerenciador de Bases de Conhecimento (denominado Rhesus em alusão à sua finalidade experimental é proposto e especificado, objetivando confirmar a viabilidade técnica do desenvolvimento de aplicações baseadas em lógica e hiperredes. / In spite of its inherent undecidability and the negation problem, extensions of first-order logic have been shown to be able to overcome the question of the monotonicity, establishing knowledge representation schemata with virtuatLy universal expressiviness. However, one still has to solve, or at Least to reduce the consequences of the control problem, which constrains the use of Logic-based systems to either small or medium-sized applications. Investigations in this direction [BOW 85] [MON 88] indicate that the key to overcome the inferential explosion resides in the proper knowledge structure representation, in order to have some control over possible derivations. The Hypernets Model [GEO 85] seems to reach such goat, considering its high structural power and the features that it offers to deal with descriptive, operational and organizational knowledge. Besides, the simplicity and syntactical uniformity of its primitive notions allows a very clear definition for its semantics, based, for instance, on graphs. This work is an attempt to associate logic programming with the hypernets formalism, in order to get a new model, preserving the expressiveness of the former and the heuristic and structural power of the latter. First we try to get a clear notion of the nature of knowledge and its main aspects, intending to characterize the knowledge representation problem. Some knowledge representation schemata (production systems, semantic networks, frame systems, Logic programming and the Krypton Language) are studied and characterized from the point of view of their expressiveness, heuristic power and notational convenience. Logic programming is the subject of a deeper study, under the model-theoretic and proof-theoretic approaches. Logic programming systems - in particular the Prolog Language and metateuel extensions- - are investigated as knowledge representation schemata, considering its syntactic and semantic aspects and its relations with Data Base Management Systems. The hypernets model is presented, introducing the concepts of hypernode, hyperrelation and prototype, as well as the particular properties of those entities. The Hyper language, for the handling of h y pernets, is formally specified. Prolog is used as a formalism for the representation of Knowledge Bases which are structured as hypernets. Under this approach a Knowledge Brie is seen rrG a (possibly empty) set of structured objects, which are classified as hypernodes, hyperreLations or prototypes. A mechanism for top-down reasoning on hypernets is proposed, introducing the concepts of aspect and vision, which are taken as first-class objects in the sense that they could be (-Ysigned as values to variables. We study the requirements for the construction of a Knowledge Base Management System from the point of view of the user's need-1', knowledge engineering support and implementation issues, actually supporting the concepts and abstractions (classification, generalization, association and aggregation) rYsociated with the proposed model. Based on the conclusions of this study, a Knowledge Base Management System (called Rhesus, refering to its experimental objectives) is proposed, intending to confirm the technical viability of the development of applications based on logic and hypernets.
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Absorption Flow-Cytometry for Point-of-Care DiagnosticsBanoth, Earu January 2017 (has links) (PDF)
Medical devices are used widely at every stage of disease diagnosis and treatment. To eradicate certain infectious diseases, the development of highly sensitive diagnostic tools and techniques is essential. The work reported in this thesis presents a novel approach, which can be used for the diagnosis of various diseases in the field of clinical cytology. The central theme of this approach was to develop a simple, holistic and completely automated system for point-of-care (POC) diagnostics. This is realized through the Development of an Absorption Flow-Cytometer with Synergistic Integration of Microfluidic, Optics and simple Electronics. Quantitative diagnosis of malaria has been taken as test case for the characterization and validation of the developed technology.
Malaria is a life-threatening disease widely prevalent in developing countries. Approximately half the world population undergoes a test of malaria and it kills close to half a million people every year. Early detection and treatment will reduce the number of fatalities and also decrease its transmission rate. In the recent past, several diagnostic tools have been developed to detect malaria but there are varied demands on diagnostic instruments in healthcare settings and endemic contexts. The objective of this thesis is to develop an instrument capable of identifying malaria-infected red blood cells (i-RBCs) from a given few micro-liters of whole blood. The optical absorption properties of blood cells were measured at a single-cell level to diagnose malaria. The proof-of-concept for the instrument was established in four stages, after which a prototype was also developed and validated.
In the first stage, a system capable of simultaneously imaging cells and also measuring their optical absorbance properties was developed. The developed system was employed to characterize absorption properties of red blood cells (malaria-infected and healthy ones) on blood-smear. A custom-made bright-field transmission microscope in combination with a pair of laser diode and photo-detector was used to simultaneously image and measure transmittance of infected and uninfected RBCs.
In the second stage, the technique was extended to enable high-throughput measurements with the use of microfluidic sample handling and synchronous data acquisition. Using this technique, the optical absorbance and morphology of infected and healthy RBCs have been characterized in statistically significant numbers. The correlation between cell morphology (from images) and single-cell optical absorbance level helped to establish the thresholds for differentiating healthy and infected cells.
In the third stage, a portable prototype capable of assessing optical absorbance levels of single cells was fabricated. The developed prototype is capable of assessing cells at throughputs of about 1800 cells/ second. It was initially validated with sample suspensions containing infected and healthy RBCs obtained from malaria cultures. For the device to be usable at the field-level, it has to function in the presence of all other cellular components of whole blood. The optical absorbance of other cellular components of blood like white blood cells and platelets, were characterized. The device was finally tested with blood samples spiked with malaria-infected RBCs validating the overall proof-of-concept and the developed prototype. The deployment of such cost-effective, automated POC system would enable malaria diagnosis at remote locations and play a crucial role in the ongoing efforts to eradicate malaria. In future, the presented technology can be extended to develop POC diagnostic tool for other diseases as well.
As it enables quantitative estimation of malaria, the present optical absorption flow analyzer would also find application in disease prognosis monitoring, anti-malarial drug development and other studies requiring measurements on a single-cell basis. The hyper-imaging system can be used to characterize and validate the threshold information, and can be incorporated in the prototype. Thus, it is a continuous process to characterization and implementation in the prototype. The optofluidic absorption flow analyzer will help enable affordable clinical diagnostic testing in resource limited settings. This approach will be extended to diagnose other diseases, using differences in optical absorption as criteria for differentiating healthy and infected cells.
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Propriedades ópticas não-lineares de oligômeros de anilina / Nonlinear optical properties of aniline oligomersPaulo Licênio Franzen 29 October 2002 (has links)
Apresentamos os resultados do estudo das não-linearidades ópticas de origem eletrônica de duas moléculas da classe dos oligômeros de anilina: o dímero e o tetrâmero. Foram medidas quatro concentrações de tetrâmero, puras e também dopadas em 33 e 100%; uma de dímero pura e outra dopada em 100%. As soluções foram preparadas usando dimetil-sulfóxido (DMSO) como solvente e a dopagem foi realizada com ácido clorídrico. As amostras foram caracterizadas por medidas de absorção linear e fluorescência antes das medidas não-lineares. Obtivemos os valores da primeira hiperpolarizabilidade (?) para todas as amostras, o índice de refração não-linear (n2) do tetrâmero dopado e não dopado, e a absorção não-linear em função da intensidade e da concentração do tetrâmero. As medidas foram realizadas através das técnicas de Varredura-Z, absorção não-linear e espalhamento Hiper-Rayleigh. Os resultados foram interpretados em termos da comparação entre diferentes estados de dopagem e da variação da seção de choque do estado fundamental para o primeiro excitado. / We report on the study of electronic optical non linearities in two aniline oligomers: dimer and the tetramer. Four tetramer concentrations were measured, pure and also 33 and 100% doped; one of dimer non doped another 100% doped. The solutions were prepared using dimethyl sulfoxide (DMSO) as solvent and the doping was performed with hydrochloric acid. The samples were characterized by measurements of linear absorption and fluorescence. We obtained the values of the first hyperpolarizability (?) for all samples, the non linear index of refraction (n2) for non doped and doped tetramer, and the non linear absorption in function of intensity and concentration of the tetramer. The measurements were accomplished through the techniques of Z-Scan, non linear absorption and Hyper-Rayleigh Scattering. The results were interpreted in terms of the comparison among different doping states and of the variation of cross-section for the transition from ground to the first excited states.
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Estudo de propriedades ópticas de moléculas de chalconasSantos, Francisco de Assis 28 July 2015 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This work reports on the optical properties of chalcones molecules in solution, using methanol
as solvent. For the characterization of the linear optical properties, were obtained absorbance
spectra. While for the characterization of the nonlinear optical properties, it has been used techniques
hyper-Rayleigh scattering and Z-scan. Using hyper-Rayleigh scattering technique, were
determined the first hyperpolarizabilities of the molecules studied. With the Z-scan technique,
we could obtain the two-photon absorption spectra at several wavelengths in the range of 480
to 790 nm. From the two-photon absorption spectra were possible to determine the coefficients
of two-photon absorption and their respective cross section. The results help to understand the
effects of substituents added to the basic structure of chalcones in both linear optical properties
as nonlinear. / Neste trabalho, estudamos as propriedades ópticas de moléculas de chalconas em solução,
usando o metanol como solvente. Para a caracterização das propriedades ópticas lineares foram
determinados os espectros de absorção. Na caracterização das propriedades ópticas não lineares
foram utilizadas as técnicas de espalhamento hiper-Rayleigh e de varredura-Z. Utilizando a
técnica de espalhamento hiper-Rayleigh foram determinadas as primeiras hiperpolarizabilidades
das moléculas estudadas. Com a técnica de varredura-Z conseguimos obter os espectros de
absorção de dois fótons em vários comprimentos de onda no intervalo dos 480 aos 790 nm. A
partir dos espectros de absorção de dois fótons foi possível determinar o coeficiente da absorção
de dois fótons e sua respectiva seção de choque. Os resultados ajudam a compreender os efeitos
de substituintes, adicionados à estrutura básica das chalconas, tanto nas propriedades ópticas
lineares quanto não lineares.
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Perspectivas comunicacional e hipertextual à luz das tecnologias em educação em meio ao uso de Fóruns e Chats na Didática da Matemática / Perspectivas comunicacional e hipertextual à luz das tecnologias em educação em meio ao uso de Fóruns e Chats na Didática da Matemática / Perspective and hypertextual communication in the light of technology in education through the use of Forums and Chat the Didactics of Mathematics / Perspective and hypertextual communication in the light of technology in education through the use of Forums and Chat the Didactics of MathematicsNASCIMENTO, Weldson Luiz 26 March 2009 (has links)
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Previous issue date: 2009-03-26 / This work is the result of a qualitative research on participative nature that arouse from the
study of facts and analysis of bachelor in mathematics II (DID2), during the first semester of
2008 in the college of mathematics and statistics at Goiás Federal University (UFG). The
main purpose of this research was to verify the range on which the virtual classes could either
or neither contribute to the learning process. The study was shaped according to 50% of
presence classes and 50% of non presence ones. Virtual learning was used for non presence
activities (AVA) Moodle. In the context of the research, the researcher was a copartner in the
working up and effective accomplishment of pedagogical activities and virtual ones (AVA),
as well as a researcher in exercise in the presence and non presence activities, developed by
his/her professor. Because of the pedagogical range that the subject presented itself, thematic
cuttings were essential for data analysis. Communicational perspectives were researched then,
hyper textual information about the developed subject and the above-mentioned (AVA). With
the analysis categories of every perspective above-mentioned, interchanges of speech were
developed in forum and chats when, they were contrasted it was found the construction of an
interactive communication and expressive textual dialogue as the priority perspective
signalized. Simultaneously, the dissertation also contributed to sections, whose debates gave a
subsidy to themes, not totally clarified by the approach pertaining to a not present education
(EaD). The themes approached passed by possible differences between interaction and
interactivities, and also about the possibility to create communicational spaces, which
developed themselves. It also holds conceptions about emblematical themes, technologies of
information and communication (TIC) and (AVA). The legal base about the EaD and some
contributions examined in the development of the subject that lay the foundation and
stimulate virtual practices. In this context the research created new thoughts about
pedagogical virtual practices, mainly to involve the researched subject, a non conventional
practice in similar research in the field of Mathematics. This practice approaches a subject in
the field of education not for the specific Mathematics subject.Perspective and hypertextual communication in the light of technology
in education through the use of Forums and Chat
the Didactics of Mathematics / Este trabalho é o resultado de uma pesquisa qualitativa de cunho participativo que surgiu da
observação e da análise da disciplina Didática da Matemática II (DID2), ministrada no
primeiro semestre de 2008, no Instituto de Matemática e Estatística da Universidade Federal
de Goiás (UFG). O objetivo principal da pesquisa é verificar em que medida a utilização de
aulas desenvolvidas virtualmente pode contribuir ou não para a aprendizagem. A disciplina
configurou-se em 50% de atividades presenciais e 50% em atividades não presenciais. Nas
atividades não presenciais, utilizou-se o Ambiente Virtual de Aprendizagem (AVA) Moodle.
No contexto da pesquisa o pesquisador foi um sujeito co-participante na elaboração e
execução das atividades pedagógicas e virtuais no AVA e pesquisador das práticas
pedagógicas presenciais e não presenciais desenvolvidas por seu orientador e, também,
professor da disciplina. Pela abrangência pedagógica que a disciplina proporcionou fez-se
necessário realizar recortes temáticos para análise dos dados. Foram, então, pesquisadas as
perspectivas comunicacional e hipertextual à luz da disciplina desenvolvida e do referido
AVA. Elaboradas as categorias de análise de cada perspectiva supracitada, foram selecionadas
interlocuções desenvolvidas nos Fóruns e Chats realizados que, ao serem contrastadas,
verificaram-se as construções de um espaço comunicacional interativo e de diálogos textuais
significativos como as expectativas primeiras sinalizavam. Simultaneamente, a dissertação
contribui também com seções cujas discussões subsidiaram temas não muito esclarecidos na
abordagem sobre Educação a Distância (EaD). Os temas abordados perpassam pela ambígua
interpretação entre interação e interatividade e sobre a possibilidade de se criar espaços
comunicacionais que as desenvolvam. Tece-se, também, concepções sobre os temas
emblemáticos Tecnologias de Informação e Comunicação (TIC) e AVA, a fundamentação
legal sobre a EaD e certas contribuições observadas no desenvolvimento da disciplina que
alicerçam e estimulam práticas virtuais. Nesse contexto, a pesquisa engendra novas reflexões
sobre práticas pedagógicas virtuais, principalmente, por envolver, a disciplina pesquisada,
uma prática não convencional em pesquisas semelhantes na área da matemática. Essa prática
aborda uma disciplina da área de educação e não uma disciplina específica da Matemática.
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Não linearidades de segunda e terceira ordem de sistemas moleculares ramificados / Second and third order nonlinearities of branched molecular systemsRuben Dario Fonseca Rodriguez 26 October 2016 (has links)
Compostos orgânicos constituem uma classe interessante de materiais para aplicações em óptica por apresentarem boa processabilidade, relativa facilidade para integração em dispositivos e, principalmente, pela possibilidade de otimização de suas propriedades ópticas através da engenharia molecular. Várias estratégias têm sido empregadas para sintetizar moléculas orgânicas, que exibam singificativos efeitos ópticos não lineares. Nesta direção, nos últimos anos moléculas multi-ramificadas vêm sendo produzidas com o objetivo de intensificar efeitos não lineares, já que estas podem exibir um forte efeito cooperativo entre seus ramos. Nesta tese estudamos a relação da absorção de dois fótons (A2F) e da primeira hiperpolarizabilidade com a estrutura molecular, para um conjunto de nove derivados de trifenilamina com diferentes grupos aceitadores de elétrons arranjadas em geometrias dipolar, quadrupolar e octopolar. O processo A2F foi estudados através da técnica de Varredura-Z, enquanto que a primeira hiperpolarizabilidade foi caracterizada pela técnica de espelhamento hiper Rayleigh. Os dados experimentais para a absorção de dois fótons revelaram espectros bem definidos, com valores razoáveis de seção de choque na região do visível e infravermelho próximo. Observamos ainda um engrandecimento para a seção de choque de A2F para as moléculas quadrupolares. Os resultados obtidos para a primeira hiperpolarizabilidade (β) mostraram que moléculas quadrupolares apresentam maior β do que as dipolares e octopolares, portanto, nossos resultados permitem concluir que o acoplamento eletrônico entre os ramos contribuem fortemente para a seção de choque por A2F e β nas moléculas quadrupolares, não sendo este processo relevante nas moléculas octopolares. Todos os resultados foram interpretados por meio de estudos teóricos empregando a teoria do funcional da densidade (DFT). / Organic compounds constitute an interesting class of materials for optical applications due to their excellent processability, easy integration into devices and, mainly, the possibility of optimizing its optical properties through molecular engineering. Several strategies have been employed to synthesize organic molecules, which exhibit significant nonlinear optical effects. In this direction, in the last few years multi-branched molecules have been obtained aiming at intensifying nonlinear optical effects, since they may exhibit a strong cooperative effect among their branches. On this thesis we have studied the relationship of two-photon absorption (2PA) and first hyperpolarizability with the molecular structure of a group of nine triphenylamine derivatives attached to distinct electron acceptor groups arranged in dipole, quadrupole and octopolar geometries. The 2PA process was studied by Z-scan technique, while the first hyperpolarizability was characterized by the hyper-Rayleigh scattering technique. The experimental data for two-photon absorption revealed well-defined spectra with reasonable cross section magnitude in the visible and near infrared range. We also observed an enhancement of the 2PA cross-section for the quadrupolar molecules in comparison to the dipolar and octopolar ones. The results obtained for the first hyperpolarizability (β) shown that the quadrupolar molecules present higher β than the dipolar and octopolar, suggesting that the electronic coupling between the branches strongly contribute to the 2PA cross-section and β in quadrupolar molecules, being not relevant in the octopolar molecules. All results were interpreted through theoretical studies based on the density functional theory (DFT).
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Finding missing people : Hur kan man effektivisera arbete med att söka efter försvunna personer?Lugnegård, Mikael January 2015 (has links)
Finding missing people and obtaining an overview of complex emergencies is very demanding and requires costly resources. I have on a few occasions sought after my grandfather, who, when he got Alzheimer, liked to go for a stroll at night (!) when my grandmother was sleeping. Those kind of situations are very stressful, especially a cold winter night. During my first 25 years I was part of a dedicated outdoor culture with countless ski trips, mountain hikes, mountain bike trips and many hours in primarily Swedish nature. It happened on a few occasions that we came in contact with people who worked with rescue operations in this type of environment. It could be about hikers who strayed away or been injured in the inaccessible nature, lost skiers in the mountain massifs around Riksgränsen, berry pickers in the Västerbotten forests etc. There are many examples of this type of situations and it's reflections on these scenarios and similar current problem which is the basis for this project. Every year, about 7000 people are reported missing in Sweden. Of these remains about 30-35 vanished. Globally, the figure is huge. Earthquakes, floods and other hit by natural occurs despite various preventive measures. There are many occasions where the search, reconnaissance and location of individuals as well as physical problems play a critical role, but where human capacity seldom is sufficient. Search party chains (organized by organisations like Missing People) requires significant human resources and costs precious time, police helicopter reconnaissance is economically very costly, not environmentally friendly and involves a significant margin of error. With these statements as background, I would look at the possibility of creating a thorough design solution that contributes to people in need can be located, provided security and helped significantly faster than today without requiring significant resources. With this as a backdrop, I wanted to create a concept that would contribute to that more people were found and could be saved. Through an extensive research of how a rescue operation is conducted, interviews with police and Missing People, as well as observations during actual operations, I identified a few main problem areas that my concept generation would center around. Together with my sponsor, we wanted to create something that can best be described as a robotic eagle with hyper vision, long flight time and a positive association for the victim. The result is Aetos (Greek for eagle). A modular drone-system with innovative features to handle with long flights and demanding rescue missions. Thanks to an aerodynamic shape and a remote-controlled system Aetos requires minimal resources to create overview and help in locating the missing person. We want to save lives, and it can Aetos that.
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