Paisagens Catóptricas: espelhos e aberrações em metrópoles investiga, por meio de ensaios visuais e considerações teóricas, alguns aspectos da força poética da cidade refletida nela mesma enquanto particularidade da paisagem. Nos ensaios visuais, elaborados a partir de registros fotográficos de superfícies reflexivas paulistanas ao longo de 2018, as imagens especulares transmutam- se em impressas por meio da cianotipia e do marrom Van Dyke - ambos decalques fotográficos monocromáticos. A conjugação das imagens opera uma cartografia traçada em derivas pela cidade na busca por espelhamentos insólitos, por aberrações sugestivas de nexos entre o imaginário e a catóptrica, sendo esta a parte da Óptica que estuda espelhos. O conjunto de imagens se inscreve na noção de paisagem como representação cultural informada pela pintura e delimita o campo para a discussão dos procedimentos adotados na confecção das próprias imagens. Os ensaios visuais também orientam as pesquisas sobre referências teóricas que relacionam o espelho à literatura e às artes visuais, repertório que retroage em benefício da invenção continuada das imagens, à medida que aguça o olhar artializador dirigido à cidade. São também apresentados parâmetros para a discussão das instâncias in visu e in situ do que aqui se define como paisagem catóptrica, ou seja, imagens especulares da cidade visíveis em superfícies reflexivas delimitadas da própria cidade. / Catoptric landscapes: mirrors and aberrations in metropolis investigates, through visual essays and theoretical considerations, some aspects of the poetic force of the city in-itself reflected as a particularity of the landscape. In these essays, constructed upon photographic records of São Paulo reflective surfaces throughout the year of 2018, the specular images transmute themselves into print images by means of cyanotype and of van Dyke brown - both monochromatic photographic decals. The images\' conjugation operates a cartography drawn in drifts around the city, pursuing some unusual mirroring and suggestive aberrations of nexus between the imaginary and the Catoptrica - herein the part of the Optics that studies mirrors. This set of images are under the notion of landscape as cultural representation informed by painting and bounds the field for the discussion of the adopted procedures in the making of the same images. The visual essays also guide the research on theoretical references that relate the mirror to literature and the visual arts, a repertoire that acts in the benefit of the continuous invention of the images by sharpening the artialising look towards the city. Some parameters are also presented, in a way to enable the discussion of the in visu and in situ instances of what herein is defined as catoptric landscape, that is, specular city images visible on delimited reflective surfaces of the city itself.

<p>In the genre of the-mirror-for-princes Erasmus Desiderius, <em>Institutio Principi Christiani</em> and Niccoló Machiavelli’s <em>Il Principe</em> are traditionally considered as a dichotomy. This thesis aims at comparing Erasmus against the norm of Machiavelli with emphasis on genre and rhetoric. A "reversed" comparative reading like this study shows that much of what is considered typical of the genre in Erasmus classic is in fact a result of the use of ethos and decorum. The study concentrates on the uses of normative language on the subjects of education, virtue, war, love, and hate to answer how the two texts differentiate in view of the legitimacy of rulers and how these differing views can be explained. This unorthodox reading of Erasmus mirror-for-princes reveals a less naïve and more pragmatic ideal prince. Though clearly separate from Machiavelli’s prince, formed by the roman discourse, the Erasmian ruler is hard to define as its antithesis. The differences in outlook constitute two different rhetorical stances in the face of the new political situation of the time and therefore share much common ground.</p>

In the genre of the-mirror-for-princes Erasmus Desiderius, Institutio Principi Christiani and Niccoló Machiavelli’s Il Principe are traditionally considered as a dichotomy. This thesis aims at comparing Erasmus against the norm of Machiavelli with emphasis on genre and rhetoric. A "reversed" comparative reading like this study shows that much of what is considered typical of the genre in Erasmus classic is in fact a result of the use of ethos and decorum. The study concentrates on the uses of normative language on the subjects of education, virtue, war, love, and hate to answer how the two texts differentiate in view of the legitimacy of rulers and how these differing views can be explained. This unorthodox reading of Erasmus mirror-for-princes reveals a less naïve and more pragmatic ideal prince. Though clearly separate from Machiavelli’s prince, formed by the roman discourse, the Erasmian ruler is hard to define as its antithesis. The differences in outlook constitute two different rhetorical stances in the face of the new political situation of the time and therefore share much common ground.

The human face has a fascinating capability to express emotions. The facial feedback hypothesis suggests that the human face not only expresses emotions but is also able to send feedback to the brain and modulate the ongoing emotional experience. It has furthermore been suggested that this feedback from the facial muscles could be involved in empathic reactions. This thesis explores the concept of emotional empathy and relates it to two aspects concerning activity in the facial muscles. First, do people high versus low in emotional empathy differ in regard to in what degree they spontaneously mimic emotional facial expressions? Second, is there any difference between people with high as compared to low emotional empathy in respect to how sensitive they are to feedback from their own facial muscles? Regarding the first question, people with high emotional empathy were found to spontaneously mimic pictures of emotional facial expressions while people with low emotional empathy were lacking this mimicking reaction. The answer to the second question is a bit more complicated. People with low emotional empathy were found to rate humorous films as funnier in a manipulated sulky facial expression than in a manipulated happy facial expression, whereas people with high emotional empathy did not react significantly. On the other hand, when the facial manipulations were a smile and a frown, people with low as well as high emotional empathy reacted in line with the facial feedback hypothesis. In conclusion, the experiments in the present thesis indicate that mimicking and feedback from the facial muscles may be involved in emotional contagion and thereby influence emotional empathic reactions. Thus, differences in emotional empathy may in part be accounted for by different degree of mimicking reactions and different emotional effects of feedback from the facial muscles.

Silicon-on-insulator (SOI) technology has become increasingly attractive because of the strong light confinement, which significantly reduces the footprint of the photonic components, and the possibility of monolithically integrating advanced photonic waveguide circuits with complex electronic circuits, which may reduce the cost of photonic integrated circuits by mass production. This thesis is dedicated to numerical simulation and experimental performance measurement of passive SOI waveguide devices. The thesis consists of two main parts. In the first part, SOI curved waveguide and corner turning mirror are studied. Propagation losses of the SOI waveguide devices are accurately measured using a Fabry-Perot interference method. Our measurements verify that the SOI corner turning mirror structures can not only significantly reduce the footprint size, but also reduce the access loss by replacing the curved sections in any SOI planar lightwave circuit systems. In the second part, an optical 90o hybrid based on 4 × 4 multimode interference (MMI) coupler is studied. Its quadrature phase behavior is verified by both numerical simulations and experimental measurements.

Adaptive optics (AO) systems make use of active optical elements, namely wavefront correctors, to improve the resolution of imaging systems by compensating for complex optical aberrations. Recently, magnetic fluid deformable mirrors (MFDM) were proposed as a novel type of wavefront correctors that offer cost and performance advantages over existing wavefront correctors. These mirrors are developed by coating the free surface of a magnetic fluid with a thin reflective film of nano-particles. The reflective surface of the mirrors can be deformed using a locally applied magnetic field and thus serves as a wavefront corrector. MFDMs have been found particularly suitable for ophthalmic imaging systems where they can be used to compensate for the complex aberrations in the eye that blur the images of the internal parts of the eye. However, their practical implementation in clinical devices is hampered by the lack of effective methods to control the shape of their deformable surface. The research work reported in this thesis presents solutions to the surface shape control problem in a MFDM that will make it possible for such devices to become integral components of retinal imaging AO systems. The first major contribution of this research is the development of an accurate analytical model of the dynamics of the mirror surface shape. The model is developed by analytically solving the coupled system of fluid-magnetic equations that govern the dynamics of the surface shape. The model is presented in state-space form and can be readily used in the development of surface shape control algorithms. The second major contribution of the research work is a novel, innovative design of the MFDM. The design change was prompted by the findings of the analytical work undertaken to develop the model mentioned above and is aimed at linearizing the response of the mirror surface. The proposed design also allows for mirror surface deflections that are many times higher than those provided by the conventional MFDM designs. A third contribution of this thesis involves the development of control algorithms that allowed the first ever use of a MFDM in a closed-loop adaptive optics system. A decentralized proportional-integral (PI) control algorithm developed based on the DC model of the wavefront corrector is presented to deal mostly with static or slowly time-varying aberrations. To improve the stability robustness of the closed-loop AO system, a decentralized robust proportional-integral-derivative (PID) controller is developed using the linear-matrix-inequalities (LMI) approach. To compensate for more complex dynamic aberrations, an Hinf controller is designed using the mixed-sensitivity Hinf design method. The proposed model, design and control algorithms are experimentally tested and validated.

Adaptive optics (AO) systems make use of active optical elements, namely wavefront correctors, to improve the resolution of imaging systems by compensating for complex optical aberrations. Recently, magnetic fluid deformable mirrors (MFDM) were proposed as a novel type of wavefront correctors that offer cost and performance advantages over existing wavefront correctors. These mirrors are developed by coating the free surface of a magnetic fluid with a thin reflective film of nano-particles. The reflective surface of the mirrors can be deformed using a locally applied magnetic field and thus serves as a wavefront corrector. MFDMs have been found particularly suitable for ophthalmic imaging systems where they can be used to compensate for the complex aberrations in the eye that blur the images of the internal parts of the eye. However, their practical implementation in clinical devices is hampered by the lack of effective methods to control the shape of their deformable surface. The research work reported in this thesis presents solutions to the surface shape control problem in a MFDM that will make it possible for such devices to become integral components of retinal imaging AO systems. The first major contribution of this research is the development of an accurate analytical model of the dynamics of the mirror surface shape. The model is developed by analytically solving the coupled system of fluid-magnetic equations that govern the dynamics of the surface shape. The model is presented in state-space form and can be readily used in the development of surface shape control algorithms. The second major contribution of the research work is a novel, innovative design of the MFDM. The design change was prompted by the findings of the analytical work undertaken to develop the model mentioned above and is aimed at linearizing the response of the mirror surface. The proposed design also allows for mirror surface deflections that are many times higher than those provided by the conventional MFDM designs. A third contribution of this thesis involves the development of control algorithms that allowed the first ever use of a MFDM in a closed-loop adaptive optics system. A decentralized proportional-integral (PI) control algorithm developed based on the DC model of the wavefront corrector is presented to deal mostly with static or slowly time-varying aberrations. To improve the stability robustness of the closed-loop AO system, a decentralized robust proportional-integral-derivative (PID) controller is developed using the linear-matrix-inequalities (LMI) approach. To compensate for more complex dynamic aberrations, an Hinf controller is designed using the mixed-sensitivity Hinf design method. The proposed model, design and control algorithms are experimentally tested and validated.

Journalism's role in the “Twitter age” is becoming an increasingly hot topic in media studies. This thesis was aimed at analyzing the media portrayal, with special emphasis on the difference between traditional and citizen journalism, in one of the UK’s most talked about recent short films on the media topic, Black Mirror – The National Anthem, and how this could affect the public. Qualitative methods were used to examine the portrayal of both traditional journalism and citizen journalism in the film and the effects aspect was researched through focus group interviews. The results of the content analysis showed that the film depicts traditional journalism as seriously challenged by the speed and extent that citizen journalism can reach through social media – but it also shows a dark side of citizen journalism. My content analysis came to support the idea that the negative portrayal of journalism in the film can affect the public opinion on journalism, in an indirect and complex way.

In this thesis we use the method of Semantic Mirrors to create a graph of words that are semantically related to a seed word. Spectral graph partitioning methods are then used to partition the graph into subgraphs, and thus dividing the words into different word senses. These methods are applied to a bilingual lexicon of English and Swedish adjectives. A panel of human evaluators have looked at a few examples, and evaluated consistency within the derived senses and synonymy with the seed word.

In the past three decades, Nd:YAG has been the dominating high power solid-state laser gain medium. Compared with Nd:YAG, Yb:YAG has lower quantum defects which produces less heat so that it can reduce thermo-optical deformation. In addition, the achieved doping concentration can be 100%, and the absorption FWHM at 941 nm is 18 nm. Based on above listed advantages, Yb:YAG has the potential to replace Nd:YAG. Using Yb:YAG as the laser gain medium in reentrant two-mirror laser cavity, we have succeeded in Yb:YAG ring laser and all the intracavity elements are coated by our electron gun deposition system. The main purpose of my research is to continue the previous result (slope efficiency: 20.1%), and further increasing the slope efficiency of our ring cavity with different round-trip transmittance of couplers. Besides, we measured and analyzed the polarization of the planar and non-planar ring cavities. At present, the highest slope efficiency we achieved is 38.9% with a round-trip transmittance of 16.4%.