Es wird ein "off-axis" Aufbau zur digitalholographischen Mikroskopie in Durchlicht- und Auflichtanordnung vorgestellt, der gleichzeitig hoch aufgelöste "full-field" Amplituden- und quantitative Phasenkontrastmikroskopie ermöglicht. Dabei werden verschiedene Algorithmen zur numerischen Rekonstruktion der komplexen Objektwelle bzgl. ihrer Eignung für die mikroskopische Anordnung miteinander verglichen. Durch Kombination eines beugungsfreien räumlichen Phasenschiebeverfahrens, das die Rekonstruktion ohne "Twin-Image" und nullte Beugungsordnung ermöglicht, und der Auswertung des Fresnel-Kirchhoff''schen Beugungsintegrals mit der Faltungsmethode werden die besten Ergebnisse erzielt. Die gleichzeitige Rekonstruktion der Amplitude und der Phase der Objektwelle aus einem einzigen Hologramm erfordert die mathematische Beschreibung der räumlichen Phasenverteilung in der Hologrammebene. Zur Bestimmung der Modellparameter wurde ein effizienter Algorithmus entwickelt und hinsichtlich seiner Genauigkeit getestet. Darüber hinaus wurde der Zusammenhang zwischen axialer Probenposition und dem Rekonstruktionsabstand, dessen Kenntnis zur quantitativen Auswertung und für eine rein numerische Fokussierung notwendig ist, hergeleitet. Anhand von Untersuchungen an technischen Objekten werden die laterale Auflösung und die Phasenauflösung des Systems quantifiziert und weitere experimentelle Parameter optimiert. Transparente biologische Proben, wie lebende Zellen, werden in Durchlichtanordnung analysiert. Dabei ist zur Bestimmung der Zelldicke die Kenntnis der Brechungsindizes von Zelle und Medium erforderlich. Hierfür wird ein experimentelles Verfahren vorgestellt, das die Abschätzung des integralen Brechungsindexes von Einzelzellen anhand ihrer rekonstruierten räumlichen Phasenverteilung ermöglicht. Exemplarisch wird Zelldifferenzierung aufgrund morphologischer Eigenschaften nachgewiesen und es werden Ergebnisse dynamischer Untersuchungen an lebenden Zellen gezeigt und diskutiert. / An off-axis setup for digital holographic microscopy in incident and transmission light arrangement for simultaneous high resolution full field amplitude and quantitative phase contrast microscopy is presented. Different kinds of algorithms for numerical reconstruction of the complex object wave are compared concerning their applicability to the microscopy arrangement. By combining a non-diffractive spatial phase shifting algorithm that performs reconstruction without the disturbing terms twin image and zero order with the numerical evaluation of the Fresnel-Kirchhoff diffraction integral by a convolution method we achieve best results. The simultaneous reconstruction of the object wave''s amplitude and phase from a single hologram requires a mathematical model of the spatial phase distribution within the hologram plane. An efficient numerical algorithm has been developed for determining the model''s parameters automatically and tested concerning its accuracy. Furthermore, the relation between the axial position of the object and the distance of reconstruction which is required for the quantitative evaluation of the reconstructed images and the application of a pure numerical focus is derived. Technical objects were used to quantify the lateral resolution and the phase resolution of the system and to optimize several parameters of the setup. Biological probes such as living cells are analyzed in transmission light arrangement. As a result the knowledge of the refractive index of the medium and the cell is required to derive the cell''s thickness from the reconstructed phase. Thus a special experimental method for the approximation of the integral refractive index of single cells from the reconstructed phase has been developed. Finally results of cell differentiation by morphological varieties as well as results of stimulated dynamic morphological changes are presented and discussed.

De maneira geral, a necessidade de melhorar o desempenho e diminuir o tamanho de sistemas mecatrônicos tem levado a indústria moderna a desenvolver mecanismos de posicionamento com características excelentes de aceleração e precisão. O uso de posicionadores em equipamentos de precisão, em particular no posicionamento da ferramenta/peça na usinagem de ultraprecisão, deve-se à necessidade de se obter rígido controle do perfil a ser fabricado. Neste sentido, foi desenvolvido no Laboratório de Engenharia de Precisão da EESC-USP um microposicionador angular rotativo capaz de monitorar a posição da ferramenta em relação à peça durante o processo de usinagem e fazer as devidas compensações de erros, além da possibilidade de obtenção de geometrias diferenciadas. Neste trabalho encontram-se estudos referentes à aplicação do método dos elementos finitos com o intuito de verificar a funcionalidade do sistema mecânico proposto, avaliando suas características estáticas e dinâmicas. Além disso, propõe-se validar o uso de redes neurais artificiais como ferramenta capaz de auxiliar no desenvolvimento de um algoritmo de identificação de imagens, baseado no conhecimento, que emprega como elemento multi-sensor, imagens interferométricas, representando posições. Dentre as principais características a serem alcançadas pelo algoritmo idealizado está a habilidade de identificar a posição de uma superfície justaposta ao sistema microposicionador angular e, assim, permitir maior rapidez de processamento das informações, possibilitando seu emprego em sistemas de controle em tempo real. A aplicação desta técnica foi avaliada por meio de simulação e apresenta resultados significativos para incentivar pesquisas envolvendo imagens interferométricas. / In broad terms, to achieve high performance and miniturization of mechatronic systems it is necessary to develop positioning mechanisms with high response and precision. The use of positioning devices compatible with precision equipment, particularly in the positioning of a tool relative to a workpiece in ultraprecision machining, results from the need for absolute control of the dimensions of cut. A microtilt stage was developed in the Precision Engineering Laboratory of EESC-USP which is capable of monitoring the position of a diamond tool relative to a workpiece, in-process, permiting error compensation and the generation of complex forms. Finite Element Method is applied to perform a functional analysis (static and dynamic) of the mechanical parts. The use of artifitial neural networks as a tool to help the development of an algortithm for the identification of images is proposed. This algorithm is based on knowledge and employs interferograms as a multi-sensor element representing positions. One desired characteristic of the proposed algorithm is its ability to perform the identification of the position of a surface on the tilt stage and to permit fast processing of the information. This turns the device appropriate to be used in real time applications. This technique was assessed by simulation and presented significant results, encouraging further researches envolving interferometric pattern recognition.

Atom interferometers and gyroscopes are highly sensitive atom-optical devices which are capable to measure inertial, gravitational, electric, and magnetic fields and to sense rotations. Theoretically, the signal-to-noise ratio of atomic gyroscopes is about a hundred billion times more than that of their optical counterparts for the same particle flux and the enclosed area. Ultra cold atoms from a Bose-Einstein condensate (BEC) can easily be controlled and coherently manipulated on small chips by laser pulses. Atom-optical devices will therefore play a significant role in fundamental research, precision measurements, and navigation systems. In BEC-based atom interferometers, a BEC in a trap is split by using laser pulses, the split clouds are allowed to evolve, they are reflected, and then recombined by laser pulses to observe interference. The split clouds accumulate spatial phase because of the trap and the nonlinearity caused by atom-atom interactions. A velocity mismatch due to reflection laser pulses also introduces a phase gradient across each cloud. These factors contribute to spatial relative phase between the clouds at recombination, causing the loss of contrast of the interference fringes. The main objective of this dissertation is to study the dynamics of a split condensate in atom Michelson interferometers, investigate the effect of trap frequencies, nonlinearity, and the velocity mismatch on the contrast, and to obtain the best theoretical limit of performance in terms of the experimental parameters: trap frequencies, number of atoms, and the velocity imparted to the clouds by the splitting laser pulses.

Depuis la découverte des rayons X par Röntgen, l'imagerie radiographique utilise le contraste d'absorption. Cette technique est efficace uniquement si les objets à étudier sont suffisamment absorbants. C'est pour cela qu'on peut détecter une lésion osseuse avec une radiographie, mais pas une lésion ligamentaire.Toutefois, l'imagerie par contraste de phase peut permettre de surmonter cette limite. Depuis les années 2000, s'appuyant sur des travaux similaires existant en optique visible, les scientifiques des rayons X essayent de mettre au point des dispositifs sensibles au contraste de phase et compatibles avec des applications industrielles comme l'imagerie médicale ou le contrôle non-destructif. Néanmoins, les architectures classiques des interféromètres sont très difficiles à mettre en place dans les rayons X durs, et sont trop contraignantes pour être transférables vers l'industrie. C'est pourquoi des dispositifs utilisant des réseaux de diffraction ont été les plus développés. Ils ont permis d'obtenir les premières images de radiographie par contraste de phase sur des humains vivants.Mais les architectures proposées aujourd'hui utilisent plusieurs réseaux et son contraignantes pour les industriels. C'est pourquoi j'ai développé au cours de ma thèse un système n'utilisant qu'un unique réseau de phase. J'ai montré qu'un tel dispositif peut générer des interférogrammes achromatiques et invariants par propagation. Ce dispositif a permis d'effectuer des mesures de contraste de phase quantitatives sur un fossile biologique, ainsi que des mesures métrologiques sur des miroirs plans sensibles aux rayons X. / Since Röntgen discovered X-rays, X-ray imaging systems are based on absorption contrast. This technique is inefficient for weakly absorbing objects. As a result, X-ray standard radiography can detect bones lesions, but cannot detect ligament lesions.However, phase contrast imaging can overcome this limitation. Since the years 2000, relying on former works of opticians, X-ray scientists are developing phase sensitive devices compatible with industrial applications such as medical imaging or non destructive control.Standard architectures for interferometry are challenging to implement in the X-ray domain.This is the reason why grating based interferometers became the most promising devices to envision industrial applications. They provided the first x-ray phase contrast images of living human samples.Nevertheless, actual grating based architectures require the use of at least two gratings, and are challenging to adapt on an industrial product. So, the aim of my thesis was to develop a single phase grating interferometer. I demonstrated that such a device can provide achromatic and propagation invariant interference patterns. I used this interferometer to perform quantitative phase contrast imaging of a biological fossil sample and x-ray flat mirror metrology.

Orientador: Cláudio Kitano / Resumo: A manufatura de micro e nano dispositivos vem se tornado um mercado de grande representação na indústria moderna, onde destacam-se a indústria médica, eletrônica e mecatrônica, que necessitam de dispositivos capazes de movimentar ou manipular elementos de dimensões microscópicas, tais como micro-pipetas em cirurgias, posicionamento de máscaras de chips, de amostras em microscópios de força atômica, entre outros. Neste contexto, os atuadores piezoelétricos flextensionais são dispositivos consagrados quanto ao uso na micro e nano manipulação. A solução analítica destes atuadores normalmente é muito complexa ou até mesmo impossível e, diante disso, há a necessidade de efetuar a caracterização experimental do atuador após sua confecção. A interferometria óptica é uma técnica muito precisa de medição de pequenos deslocamentos. O interferômetro volumétrico é normalmente montado sobre uma mesa óptica (breadboard) por meio de estruturas comerciais para montagem de experimentos ópticos. Diante disso, o atuador é fixado ao breadboard por estruturas como postes, deslocadores cinemáticos de translação, rotação e tilt, etc. Dessa forma, neste trabalho, levantou-se a resposta em frequência de um protótipo de atuador piezoelétrico flextensional multi atuado que foi projetado e confeccionado no Departamento de Engenharia Mecatrônica e de Sistemas Mecânicos da Escola Politécica da USP - EPUSP. Utilizou-se um interferômetro de Michelson em óptica volumétrica, e, posteriormente, um interferômet... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The manufacture of micro and nano devices has become a market of great prominence in the modern industry, where the medical, electronic and mechatronic industries stand out that need devices capable of repositioning or manipulating elements of microscopic dimensions, such as micro-pipettes in surgeries, positioning of chip masks, adjusting of samples in atomic force microscopes, among others. In this context, flextentional piezoelectric actuators are appropriated devices for use in micro and nano manipulation. The analytical solution of these actuators is usually very complex or even impossible, and there is a need to characterize the actuator after its manufacturing. Optical interferometry is a very precise technique for measuring small displacements and consequently, primissing for the caracterization of these piezoelectric atuators. The bulk interferometer is usually mounted on an optical table (breadboard) by means of commercial precision kinematic optical mounts, such as posts, tilt platformors, translations and rotation stages, and others. In this work, the frequency response of a multi-actuated flextensional piezoelectric actuator prototype, designed and manufactured at the Department of Mechatronics and Mechanical Systems of the Polytechnic School of USP - EPUSP, was investigated. Both, a Michelson interferometer and a double Michelson interferometer were applied for the simultaneousmeasurement of the displacement of the actuator in the X and Y directions. The frequen... (Complete abstract click electronic access below) / Mestre

天津是中國遭受地面沉降最嚴重的城市之一。由於經濟與城市化的快速發展，新的沉降中心陸續出現在天津的郊區城鎮。本文結合L-和X-波段合成孔徑雷達(Synthetic Aperture Radar, SAR)資料，利用雷達干涉測量(SAR Interferometry, InSAR)時間序列分析，旨在加強天津郊區的沉降監測能力。先進的基於SAR資料的遙感技術，永久散射體干涉測量(Permanent Scatterers, PS)技術被證明是一種有效的，大範圍的，低成本的沉降監測手段。 / 工作在X波段(波長為3.1cm)的TerraSAR (TSX)衛星可以提供新一代具有高解析度(1米)和短重放週期(11天)的SAR資料，從而能夠更快的獲取適用於干涉的時間序列的資料，並且適用於單個建築物的沉降觀測。然而，利用X-波段在森林或植被覆蓋區域並不能得到有效資訊。ALOS衛星的SAR感測器工作在L波段，由於波長更長(波長為23cm)，穿透力更強，所以在植被覆蓋區域也具有良好的相干性。但是ALOS衛星的SAR資料解析度更低(7米)，重放週期更長(46天)。從這兩個波段的資料特徵來看，他們可以被認為是互補的。所以，結合這兩個波段的資料可以增強沉降監測的能力和提供更為可靠的結果。儘管ALOS衛星於2011年4月22日停止了工作，我們的研究結果仍然可以為結合不同波段的SAR資料進行沉降監測提供普遍適用的結論，並為以後的研究工作提供參考。 / 在研究中，我們提出了結合L和X波段的InSAR時間序列分析策略。此策略不僅可以作為X波段資料最優化獲取方案，而且可以成為快速，高精度，低成本，多級，大範圍監測策略。 / 其次，我們基於多時序SAR資料，利用PS和准PS(Quasi-PS, QPS)技術進行了L波段與X波段的沉降監測能力探尋。L波段和X波段的時間序列分析所得到的沉降模式有很好的吻合性，都監測出三個主要的沉降中心，其中包括一個新近發現的沉降中心位於南河鎮。 / X波段的PS分析結果顯示出高密度的PS點，證實了它可以用於同時監測星狀分佈的多個城鎮。結果也表明了高解析度TSX資料可以監測到線狀地物如鐵路，高速公路以及電力線的細節資訊和沉降資訊，這些可以成為高解析度PS技術在中國的重要應用。 / 除此之外，我們利用水準資料驗證了L和X波段的處理結果，並且對地面沉降的過程進行了研究。由於水準資料和PS監測結果在時間和空間維上的採樣差別很大，所以我們對這兩者比較所具有的不確定性進行了詳細分析。結果表明了這兩種監測資料具有很好的一致性。 / 最後，我們發現在天津抽取地下水是引起地面沉降的一個主要原因。根據PS結果和地質資料，我們發現地質因素可能是另一個用於解釋沉降中心位置和形狀的原因。 / The aim of this dissertation is to enhance the capability of monitoring subsidence in Tianjin suburbs by combining L- and X-band Synthetic Aperture Radar (SAR) data with Interferometry (InSAR) time series analysis. Tianjin is located in one of the major subsidence regions in China and several new subsiding centers have been found in the suburbs of Tianjin. Advanced remote sensing technique, Permanent Scatterers (PS) based on SAR data has been found to be a feasible way to detect and monitor wide area ground subsidence at a low cost. / TerraSAR X-band (TSX) of short wavelength (3.1 cm) provides new generation SAR data with high spatial resolution of 1 m and short revisit period of 11 days. It maintains the capability to fast build up interferometric stack, and to measure the subsidence of individual features, while almost no information can be detected with X-band in the forested and vegetated areas. ALOS L-band signal of longer wavelength (23cm) penetrates deeper into the vegetation cover and depicts higher coherence over non-urban areas, while the spatial resolution is relatively lower (7m) and revisit time is longer (46 days). The characteristics of these two bands can be regarded as complementary. Combining L- and X-band can enhance abilities of subsidence monitoring and provide more reliable results. Although ALOS died on April 22, 2011, this research work will provide general answers for combining different bands of SAR data to monitor subsidence, and give suggestions for future research work. / In this research work, we have developed the strategy of combining L- and X-band with InSAR time series analysis. This strategy can not only be an optimized X-band acquisition plan, but also be a multi-level wide area monitoring strategy of subsidence with fast extraction, high precision and low cost. / Moreover, with multi-temporal SAR data, we also investigate monitoring abilities of L- and X-band by exploring PS and Quasi-PS (QPS) techniques. The subsidence patterns derived from L- and X-band InSAR time series analysis are observed to have a good agreement. Three severe land subsidence zones were detected, containing one newly discovered subsiding center located in Nanhe Town. / The X-band PS analysis shows high density of PS points and confirms its strong ability for simultaneously monitoring subsidence over star-like-distributed multiple towns. The results also demonstrate that linear constructions such as railways, highways and power lines can be detected in detail with high resolution TSX SAR data and indicates the deformation monitoring capability for large-scale man-made linear features which is a key application in China. / Furthermore, L- and X-band results were independently validated with leveling data and ground motion processes were studied. The uncertainties were comprehensively analyzed between PS results and ground leveling data, whose densities are very different in both spatial and temporal domains. The overall results show a good agreement with each other. / Finally, we find that underground water extraction is one of the major reasons for ground subsidence in Tianjin. In addition, with the integrated analysis of the PS results and the geological data, we found that lithological characteristics may be another important reason to explain location and shape of the subsiding centers. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Luo, Qingli. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 103-112). / Abstract also in Chinese. / Abstract --- p.I / TABLE OF CONTENT --- p.VI / List of Figures --- p.VIII / List of Tables --- p.XI / List of abbreviations --- p.XII / ACKNOWLEDGEMENT --- p.XIV / Chapter 1 --- INTRODUCTION --- p.1 / Chapter 1.1 --- Thesis contributions --- p.6 / Chapter 1.2 --- Thesis structure --- p.7 / Chapter 2 --- BACKGROUND --- p.9 / Chapter 2.1 --- Synthetic Aperture Radar (SAR) --- p.9 / Chapter 2.1.1 --- SAR imaging geometry --- p.9 / Chapter 2.1.2 --- SAR satellites --- p.10 / Chapter 2.2 --- Synthetic Aperture Radar Interferometry (InSAR) --- p.13 / Chapter 2.2.1 --- Introduction --- p.13 / Chapter 2.2.2 --- Principles of InSAR --- p.13 / Chapter 2.3 --- Differential Synthetic Aperture Radar Interferometry (D-InSAR) --- p.18 / Chapter 2.3.1 --- D-InSAR principle --- p.18 / Chapter 2.3.2 --- The advantages and Limits of interferometric measurements --- p.21 / Chapter 2.4.3 --- The development of PS technique --- p.22 / Chapter 2.4 --- Persistent Scatterers Interferometry (PSI) --- p.24 / Chapter 2.4.1 --- Permanent Scatterers (PS) Technique and Advantages --- p.24 / Chapter 2.4.2 --- Principle of PS technique --- p.26 / Chapter 2.5 --- QPS (Quasi-PS) Interferometry --- p.28 / Chapter 3 --- MULTI IMAGES INSAR ANALYSIS OF TIANJIN --- p.31 / Chapter 3.1 --- Introduction --- p.32 / Chapter 3.2 --- Study area and SAR data --- p.34 / Chapter 3.3 --- X-band optimized acquisition planning combing with L-band --- p.38 / Chapter 3.3.1 --- The strategy --- p.38 / Chapter 3.3.2 --- Experimental results and analyzes --- p.40 / Chapter 3.4 --- Estimating deformation maps with L- and X-band --- p.45 / Chapter 3.4.1 --- Monitoring subsidence over multiple towns and large man-made linear features with X-band --- p.45 / Chapter 3.4.2 --- The L-band QPS Results --- p.56 / Chapter 3.5 --- Conclusions --- p.58 / Chapter 4 --- VALIDATION AND INTERPRETAION --- p.61 / Chapter 4.1 --- Introduction --- p.61 / Chapter 4.2 --- Validation --- p.61 / Chapter 4.2.1 --- Leveling data --- p.61 / Chapter 4.2.2 --- Uncertainties analysis --- p.64 / Chapter 4.2.3 --- Average velocity comparison --- p.66 / Chapter 4.2.4 --- Annual displacement comparison --- p.68 / Chapter 4.2.5 --- Deformation time series: InSAR results and leveling --- p.70 / Chapter 4.2.6 --- Average velocity map comparison between InSAR results and leveling --- p.71 / Chapter 4.2.7 --- Displacement comparison between InSAR results and GNSS data --- p.73 / Chapter 4.2.8 --- Average velocity comparison between ALOS results and leveling --- p.73 / Chapter 4.3 --- Geological Interpretation --- p.74 / Chapter 4.4 --- Field survey --- p.77 / Chapter 4.5 --- QPS points analysis with aerophotograph --- p.81 / Chapter 4.6 --- Conclusions --- p.84 / Chapter 5 --- VALIDATION ALONG RAILWAY --- p.87 / Chapter 5.1 --- Introduction --- p.87 / Chapter 5.2 --- Study area --- p.87 / Chapter 5.3 --- The validation plan --- p.87 / Chapter 5.4 --- Validation with leveling data --- p.89 / Chapter 5.4.1 --- Leveling data --- p.89 / Chapter 5.4.2 --- The average subsidence rate comparison --- p.91 / Chapter 5.4.3 --- The displacement comparison --- p.95 / Chapter 5.5 --- Conclusions --- p.97 / Chapter 6 --- SUMMARY --- p.98 / The Publications --- p.102 / REFERENCES --- p.103

Megalopolises in the Pearl River Delta, including Guangzhou and Hong Kong, have experienced various degree of ground subsidence. The causes can be divided into two categories: natural subsidence and the human-induced subsidence. Monitoring the ground subsidence can not only help people to find out the distributions in both spatial and temporal fields, but also guide people to minimize the hazard ahead. Thus, it is significant to monitor the ground subsidence accurately, timely and frequently. This dissertation research uses the Environmental Satellite Advanced Synthetic Aperture Radar (ENVISAT ASAR) data received at the Chinese University of Hong Kong Satellite Remote Sensing Receiving Station and SAR Interferometry (InSAR) technology as a powerful tool for large-scale ground deformation monitoring in Guangzhou and Hong Kong areas. / Persistent Scatterer Interferometry (PSI) method is used to detect ground deformation in the urban area of Guangzhou city. A ground deformation rate map with scattered distribution of point targets shows the maximum subsidence (rise) rate as high as -26 to -20 mma-1 (16-21 mma-1 ), implying that the study area is an active zone for ground deformation. Based on the point target map, a contour ground deformation rate map is generated. All the six ground collapse accidents that occurred in 2007-2008 fall within the subsidence zones, qualitatively validating the IPTA results. Ground subsidence and geological conditions on Datansha Island are examined. The results indicate that the local geological conditions and underground engineering projects are responsible for ground subsidence and ground collapse accidents occurred there. To interpret the distribution of active ground subsidence zones, a local geological map is used as a reference for generating a series of thematic maps. The results show that geological faults, rock distribution, over-development, and underground engineering projects may be four factors leading to the distribution of the active ground subsidence zones. / The Hong Kong International Airport (HKIA) was built on a site of 12.5 km2, of which 75% is reclaimed foundation. Thus, the stability of ground foundation of HKIA is of public concern. I use the PSI method and ENVISAT ASAR data to detect the residual settlement rate from 19 April 2006 to 9 January 2008. I use ground truth data to develop empirical correction models for correcting systematic biases in the ASAR PSI-detected settlement rate. The corrected data follow the Lorentz distribution well, implying that the residual settlement process is dominated by two modes or categories of settlement rates. I find unreasonable positive values of the ASAR PSI-detected annual ground settlement rate, which follow a normal distribution. I draw a scatter plot with ground deformation rate value and coherence value of each point targets. Point targets with lower coherence values and greater positive values are extracted and drawn on a geographical map. Most of these point targets are located at the airport Midfield, which is under construction. A ground settlement rate map of HKIA shows that an area of the Passenger Terminal Building, and an area of the Southern Runway are two relatively stable areas, and one major continuous settlement area covers the airport Midfield. General spatial distribution patterns of ASAR PSI-detected ground settlement rate agree well with model-predicted residual settlement rates. / Zhao, Qing. / Adviser: Lin Hui. / Source: Dissertation Abstracts International, Volume: 72-04, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 147-163). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

Orientador: Cláudio Kitano / Banca: Ricardo Tokio Higuti / Banca: Luiz Antonio Perezi Marçal / Resumo: Neste trabalho estuda-se a interferometria laser, a qual constitui uma técnica adequada para determinar grandezas físicas com sensibilidade extremamente elevada. Basicamente, no interferômetro óptico, a informação a respeito do dispositivo sob teste é inserida na fase da luz. Utilizando-se o fotodiodo, promove-se a transferência de informação, do domínio óptico para o elétrico, no qual pode ser demodulada usando-se as várias técnicas disponíveis na literatura para detectar sinais modulados em fase. Ênfase é dada a um novo método de demodulação de fase óptica auto-consistente e de grande sensibilidade. Neste método, utiliza- se a modulação dada por uma forma de onda triangular e é baseado na análise do espectro do sinal fotodetectado, sendo capaz de estender a faixa dinâmica de demodulação a valores tão elevados quanto às dos métodos clássicos. Simulações dinâmicas computacionais de interferômetros ópticos são executadas em Simulink juntamente com este método, levando-se em consideração tensões de ruído eletrônico do tipo ruído branco, evidenciando a eficiência do método quando comparados com dados teóricos obtidos em Matlab. A validação experimental do método é realizada com o auxílio de um modulador eletro-óptico de amplitudes, cujas características de fase podem ser previstas analiticamente. Trata-se de um sensor polarimétrico baseado em cristal de Niobato de Lítio, em que a diferença de fase óptica induzida pela tensão elétrica aplicada pode ser determinada através de análise espectral, tal como o novo método descrito neste trabalho. Um interferômetro de Michelson homódino de baixo custo é implementado e a eficiência do novo método de demodulação de fase óptica é avaliada através de testes com atuadores e manipuladores piezoelétricos flextensionais, cujas características de linearidade são conhecidas... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In this work, has been done a study the laser interferometer, which is a technique for determining physical quantities with extremely high sensitivity. Basically, in the optical interferometer, information about the device under test modulates the phase of light. Using a photodiode, promotes the transfer of information from the optical domain for the electric, which can be demodulated using the various techniques available in literature to detect modulated signals in phase. Emphasis is given to a new method of phase demodulation of optical self-consistent and high sensitivity. The method employs a linear modulation given by a triangular waveform, and is based on analysis of the spectrum of the photodetected signal, being able to extend the dynamic range of the demodulation values as high as the classical methods. Dynamic computational simulations of optical interferometers are implemented in Simulink with this method, taking into account strains of electronic noise like white noise, indicating the efficiency of the method compared with theoretical data obtained in Matlab workspace. The experimental validation of the method is performed with the aid of an electro- optic amplitude modulator, whose phase characteristics can be analytically predicted. This is a polarimetric sensor based on lithium niobate crystal, in which the optical phase difference induced by electric voltage can be determined by spectral analysis, using new method described in this work. A low cost homodyne Michelson interferometer is implemented and the efficiency of the new method of optical phase demodulation is evaluated by testing with piezoelectric flextensional actuators whose characteristics of linearity are well known.The experimental results agree with theoretical analysis and reveal this method is more efficient than the classical methods / Mestre

Near surface measurements of seismic velocity and Q are useful in a number of situations, for example for when carrying out re-datuming and migration for depth images, or when analysing ground conditions for building. This thesis concentrates on the estimation of surface wave group and phase velocity as well as Q structure through the use of cross correlations of ambient noise recordings. Linearised tomography estimates are made for the British Isles, the Permain Basin of Texas and New Mexico, the Ekofisk Life of Field Seismic (LoFS) array and the Aquistore CO2 storage site. The results correspond well with the known geological structure and/or structure observed in velocity maps by other researchers. For the Ekofisk array a non-linearised non-linear method was also applied and the results estimated by these two methods for the Ekofisk LoFS array are compared. By non-linearised non-linear it is meant that the inversion method is fully non-linear and no linearisation has taken place in the method, this term will be used throughout this thesis for all methods which fall into this category. The tomography results from the two methods had similarities in their general structure but differences in the finer details, and so suggest that the substantial increase in time required for the non-linearised non-linear method is not justified. Linearised tomographic inversion of the Aquistore array was used to determine the potential of using ambient noise tomography for monitoring of CO2 storage sites. It was found that the repeatability of the tomography at the Aquistore site was not good enough to allow ambient noise tomography to be used for monitoring; however, it may be possible to apply the method at other sites. A Q and phase velocity inversion of the Ekofisk array is also presented, with results mostly showing excellent correlation with known geological features. It is shown that the higher frequencies are more sensitive to the effects of sea floor subsidence at the site, while lower frequencies are more sensitive to the effects of faulting. A final near surface method called ambient noise gradiometry was applied, this concentrates on estimating locations of sources of seismic energy within receiver arrays. Ambient noise gradiometry is applied to synthetic and real data for this purpose. It was found that using ambient noise gradiometry allows internal sources of energy to be identified but they produce a bias in the phase velocity tomography result. Two methods of reducing this bias are presented, both of which also provide an estimate of the source term for different sections of time of the recording.

Orientador: Cláudio Kitano / Banca: Ricardo Tokio Higuti / Banca: Ailton Akira Shinoda / Banca: Agnaldo Aparecido Freschi / Banca: Gefeson Mendes Pacheco / Resumo: Nesta tese, cinco novas técnicas de demodulação de fase óptica são propostas, as quais constituem versões melhoradas do método espectral J1...J4 clássico. As técnicas são adequadas para uso com sistemas interferométricos de dois feixes, homódinos, operando em malha aberta e sob excitação senoidal. As novas técnicas, aqui denominadas de métodos J1/J3A, J1...J3, Jm/Jm+2 e J0...J3, para medição do índice de modulação de fase, e, um novo método de medição da fase quase-estática, são de fácil implementação, não sendo afetadas pelo desvanecimento de sinal detectado, instabilidade da fonte óptica e visibilidade das franjas de interferência, possibilitando medições em tempo real. Os novos métodos espectrais foram avaliados com ruído branco, 1/f2 e fase quase-estática aleatória, usando o Matlab. Além disso, simulações dinâmicas realizadas no Simulink evidenciaram as vantagens dos novos métodos, que também foram testados em dois experimentos distintos: o primeiro foi direcionado à medições de tensões elétricas senoidais, usando um sensor óptico de tensão (SOT), baseado numa célula Pockels de cristal de niobato de lítio; o segundo, foi dedicado à medições de amplitudes de deslocamentos nanométricos de um atuador piezoelétrico flextensional (APF), usando-se um interferômetro de Michelson. Por ser um sistema que pode ser modelado analiticamente, o SOT serviu para validar os novos métodos espectrais. A caracterização de APF's usando os novos métodos ópticos é a aplicação relevante desta tese. Medições de deslocamentos no APF, desde a faixa subnanométrica até a micrométrica, realizadas usando-se os métodos J0...J3 e Jm/Jm+2, permitiram analisar sua linearidade e resposta em freqüência, as quais foram comparadas com os resultados obtidos com um analisador de impedâncias vetorial. Ambos os resultados experimentais, ...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In this work, five novel optical phase demodulation techniques are proposed, which overcome some of the limitations of the J1…J4 classical method. These improved techniques are applied with two beams, homodyne, open loop and sinusoidal phase modulation interferometer systems. These new techniques, named in this work as "J1/J3A, J1...J3, Jm/Jm+2 and J0...J3 methods," which are applied to phase modulation index measurements, and "the novel method for quasi-static phase measurements," are of simple implementation, and are unaffected by signal fading, laser source instabilities or changes in fringe visibility. In addition they allow real time measurements. The new methods were evaluated with white noise, 1/f2 noise and random fading, using Matlab/Simulink, making evident their advantages in relation to the classical methods. These methods were also tested in two experiments: the first one, corresponds to an optical voltage sensor (OVS), based on lithium niobate Pockels cell; the second one, refers to the measurement of nanometric displacement amplitudes of a piezoelectric flextensional actuator (PFA), by using a Michelson interferometer. Because the OVS has an analytic response, it was suitable to validate the new spectral methods. The characterization of the PFA by using the new optical methods is the main application of this thesis. PFA displacements, from sub-nanometer up to micrometer range were detected by applying the J0…J3 and Jm/Jm+2 methods. By measuring the PFA displacements, the linearity and frequency response of the PFA were evaluated. To confirm the observed frequencies of resonance an impedance analyzer was used to measure the magnitude and phase of the PFA admittance. Results obtained for the OVS and PFA systems, with the new methods and those produced by the J1...J4, J1...J6-neg, J1...J6-pos and J0...J2 classic methods, ...(Complete abstract, click electronic access below) / Doutor