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In this study the use of two radar interferometry methods, PSInSAR and SBAS, were tested as tools for measuring coastal erosion. If successful it would have allowed for measuring coastal erosion as a function of material lost. The study area used was Ystad municipality, in southern Sweden. Radar data for the study was provided by the ESA, the European space agency, from their ERS-2 and ENVISAT satellites, spanning the period 1998-2005. Unfortunately, even after many different configurations of settings were tested, the results indicated that both methods are very unsuited for use in rural areas such as Ystad, whether for measuring coastal erosion or otherwise. Both methods had severe problems achieving significant coverage after low coherence areas were masked out, and PSInSAR suffered from several anomalies. This is likely due to the highly vegetated nature of the landscape, which results in low coherence through temporal decorrelation. Of the two methods SBAS showed the most promise, but not nearly enough to be considereduseful. It is, based on the scientific literature, possible that simpler interferometry methods might have been more useful. This, and other possible ways to improve the results is something that this study discusses at length.

Cette thèse porte sur l’étude de la déformation de surface (petite et grande déformation) pouvant être détectée en utilisant la méthode de l’interférométrie "InSAR " pour le traitement des images SAR (Synthetic Aperture Radar, bande C : λÉ = 5.6 cm) et signal associé à synthèse d'ouverture. Les nouveaux développements des techniques de traitement InSAR permettent le suivi de la déformation en surface avec une précision de l'ordre millimétrique. Les traitements dites conventionnels de l'InSAR utilisent une paire d'images SAR ("Maitre" et "Esclave") afin de mesurer la différence de phase entre les deux prises de la même scène d'image à des moments différents. Les incertitudes dans les mesures obtenus à partir du traitement conventionnel de l'InSAR sont nombreuses : la décorrelation dans le signal en raison du délai du à l'atmosphère, la contribution topographique et les positions orbitales sont les handicaps majeurs de cette technique. En 2001, Ferretti et al. ont introduit une nouvelle méthode appelée Permanent Scatterer (PS-InSAR) également connue sous le nom de Persistent Scatterer. Pour cette méthode, nous utilisons une série d'images, dont une dite esclave pour construire des interférogrammes avec la même image dite « Maître ». Cette méthode permet d'améliorer le signal de visé (LOS) en terme de correlation pour chaque pixel (PS) en utilisant les meilleurs réflecteurs donnant une corrélation maximale (à partir de l'amplitude et/ou la phase) dans le temps et dans l'espace. Un grand nombre d'algorithmes a été élaboré à cet effet en utilisant le même principe (des variantes) décrit auparavant. En 2002, Berardino et al. publient un nouveau algorithme développé pour le suivi de la déformation en surface en se basant sur les interférogrammes produits à partir des couples d’image SAR ayant une petite séparation spatial (SBAS) de la ligne de base.Dans cette thèse, les techniques InSAR sont appliquées pour différents cas d’étude allant de la petite déformation en surface telle que: 1) Un affaissement dans une zone de puits de pétrole, 2) des glissements de terrain dans une zone urbaine, et 3) la déformation lente à travers les zones de failles des zones sismiques. Afin d'étudier la petite déformation j'opte pour l’utilisation des deux algorithmes (PS et SBAS) dit de traitement multi-temporelle de l’InSAR incorporés dans le logiciel StaMPS (Hooper, 2008). Ainsi, j’ai pu calculer la méthode de combinaison ou hybride entre PS et SBAS et ce, pour toutes les études de cas présentées dans cette thèse. Par ailleurs, certains logiciels en libre accès sont utilisés tout au long de cette thèse tel que, Roi-pac (Rosen et al., 2004) pour aligner les images SAR ainsi que Doris (Kampes et al., 2003) pour calculer interférogrammes à partir de images SAR.[...] / This thesis aims at the study of small to large surface deformation that can be detected using the remote sensing interferometric synthetic aperture radar (InSAR) methods. The new developments of InSAR processing techniques allow the monitoring of surface deformation with millimeter surface change accuracy. Conventional InSAR use a pair of SAR images (“Master” and “Slave” images) in order to measure the phase difference between the two images taken at different times. The uncertainties in measurements using the conventional InSAR due to the atmospheric delay, the topographic changes and the orbital artifacts are the handicaps of this method. The idea of InSAR method is to measure the phase difference between tow SAR acquisitions. These measure refere to the ground movment according to the satellite position. In interferogram the red to blue colors refere to the pixel movement to or far from the satellite position in Line-Of-Sight (LOS) direction. In 2000’s, Radar spacecraft have seen a large number of launching mission, SAR quisitions and InSAR applicability have seen explosion in differents geophysical studies due to the important SAR datas and facility of data accessibity. This SAR-mining needs other type and generation of InSAR processing.In 2001, Ferretti and others introduce a new method called Permanent Scatterer InSAR (PS) that is based on the use of more than one Slave image in InSAR processing with the same Master image. This method allows enhancing the LOS signal for each pixel (PS) by using the best time and/or space-correlated signal (from amplitude and/or from phase) for each pixel over the acquisitions. A large number of algorithms were developed for this purpose using thesame principle (variantes). In 2002, Berardino et al developed new algorithm for monitoring surface deformation based on the combination of stack of InSAR results from SAR couples respecting small baseline (SB) distance. Nowadays, these two methods represent the existing time series (TS) analysis of SAR images approaches. In addition, StaMPS software introduced by Hooper and others, in 2008 is able to combine these two methods in order to take advantages from both of this TS approaches in term of best signal correlation and reducing the signal noise errors. In this thesis, the time series studies of surface changes associate to differents geophysical phenomena will have two interest: the first is to highlight the PS and SBAS results and discuss the fiability of obtained InSAR signal with comparation with the previous studies of the same geophysical case or observations in the field and in the second time, the combined method will also validate the results obtained separately with differents TS techniques. The validation of obtained signal is assured by these two steeps: Both of PS and SBAS methods should give relatively the same interferograms and LOSdisplacement signal (in term of sign and values), in addition these results will be compared with the previous studies results or with observations on the field.In this thesis, the InSAR techniques are applied to different case-studies of small surface deformation [...]

This thesis aims at the study of small to large surface deformation that can be detected using the remote sensing interferometric synthetic aperture radar (InSAR) methods. The new developments of InSAR processing techniques allow the monitoring of surface deformation with millimeter surface change accuracy. Conventional InSAR use a pair of SAR images ("Master" and "Slave" images) in order to measure the phase difference between the two images taken at different times. The uncertainties in measurements using the conventional InSAR due to the atmospheric delay, the topographic changes and the orbital artifacts are the handicaps of this method. The idea of InSAR method is to measure the phase difference between tow SAR acquisitions. These measure refere to the ground movment according to the satellite position. In interferogram the red to blue colors refere to the pixel movement to or far from the satellite position in Line-Of-Sight (LOS) direction. In 2000's, Radar spacecraft have seen a large number of launching mission, SAR quisitions and InSAR applicability have seen explosion in differents geophysical studies due to the important SAR datas and facility of data accessibity. This SAR-mining needs other type and generation of InSAR processing.In 2001, Ferretti and others introduce a new method called Permanent Scatterer InSAR (PS) that is based on the use of more than one Slave image in InSAR processing with the same Master image. This method allows enhancing the LOS signal for each pixel (PS) by using the best time and/or space-correlated signal (from amplitude and/or from phase) for each pixel over the acquisitions. A large number of algorithms were developed for this purpose using thesame principle (variantes). In 2002, Berardino et al developed new algorithm for monitoring surface deformation based on the combination of stack of InSAR results from SAR couples respecting small baseline (SB) distance. Nowadays, these two methods represent the existing time series (TS) analysis of SAR images approaches. In addition, StaMPS software introduced by Hooper and others, in 2008 is able to combine these two methods in order to take advantages from both of this TS approaches in term of best signal correlation and reducing the signal noise errors. In this thesis, the time series studies of surface changes associate to differents geophysical phenomena will have two interest: the first is to highlight the PS and SBAS results and discuss the fiability of obtained InSAR signal with comparation with the previous studies of the same geophysical case or observations in the field and in the second time, the combined method will also validate the results obtained separately with differents TS techniques. The validation of obtained signal is assured by these two steeps: Both of PS and SBAS methods should give relatively the same interferograms and LOSdisplacement signal (in term of sign and values), in addition these results will be compared with the previous studies results or with observations on the field.In this thesis, the InSAR techniques are applied to different case-studies of small surface deformation [...]

Made available in DSpace on 2016-06-02T20:09:17Z (GMT). No. of bitstreams: 1 4934.pdf: 6976486 bytes, checksum: c340cf221926ec58e76bb12981626d19 (MD5) Previous issue date: 2013-01-25 / Financiadora de Estudos e Projetos / Brazil is the world's largest producer of sugarcane and the leading exporter of its derivatives (sugar, alcohol, energy etc.). One of the main waste generated in the manufacturing process of this sector is the sugarcane bagasse ash sand (SBAS), produced from the burning of bagasse into boilers to produce electricity (cogeneration). This ash sand is composed of a high amount of silica and it is also currently discarded in cane plantations as organic fertilizer, despite the fact that it is poor in nutrients. This research proposes to provide an alternative application of SBAS in concrete as a replacement material for fine aggregate. Furthermore, the durability of concrete with alternative materials demands a special attention, especially regarding reinforcement corrosion. This is a major concern of the use of wastes on the degradation of concrete structures. The process begins with the despassivation of steel reinforcement, and it propagates in a suitable environment. The aim of this study was to evaluate the potential occurrence of reinforcement corrosion in concrete made with SBAS as a partial replacement material for fine aggregate. The ash sand samples were collected in a plant in the State of São Paulo, and standardized through a sieving and grinding. The SBAS was subjected to physical and chemical characterization, by its chemical composition, sieve analysis, powdery material, absorption, bulk density and true density. Mortars and concretes were produced with levels of substitution of 0% (reference), 30% and 50% of SBAS. In mortars, tests of compressive strength, porosity (void index and pores analysis by optical microscopy), water absorption, accelerated carbonation, chloride penetration and electrical conductivity of the aqueous solution were performed. The concretes were submitted to tests of compressive strength, void index, absorption, chloride penetration, potential and rate of reinforcement corrosion. Thus, the results indicated that substitution of 30% and 50% by SBAS can increase the compressive strength of concrete and the resistance to attack by chlorides, and decrease the despassivation probability of reinforcement. However, with the content of 50% of SBAS, the corrosion rate was significantly higher in comparison to other samples, and it was similar between the concretes with 30% of SBAS and reference. Thus, it was possible to conclude that the concrete with 30% of SBAS as a substitute of fine aggregate may be applied in conventional structural elements without loss of mechanical and durability performance. / O Brasil é o maior produtor mundial de cana-de-açúcar e o principal exportador de seus derivados (açúcar, álcool, energia etc.). Um dos principais resíduos gerados no processo industrial do setor sucroalcooleiro é a areia de cinza do bagaço da cana-de-açúcar (ACBC), derivada da queima do bagaço da cana nas caldeiras para a produção de energia elétrica (cogeração) para o abastecimento das próprias usinas. Esse material, com elevada quantidade de sílica, é geralmente descartado no solo como adubo nas lavouras de canade- açúcar, mesmo sendo pobre em nutrientes. Essa pesquisa vem oferecer uma alternativa para aplicação da ACBC em matrizes cimentícias de concretos como agregado miúdo, em substituição à areia natural. Além disso, a durabilidade de concretos utilizando materiais alternativos demanda uma atenção especial, principalmente quanto à corrosão de armaduras. Esta é uma das principais preocupações na utilização de resíduos quanto à degradação de estruturas de concreto. O processo corrosivo se inicia quando ocorre a despassivação da armadura e se propaga na presença de um meio propício. Este trabalho busca, portanto, estudar e avaliar a potencialidade da ocorrência de corrosão de armaduras em concretos produzidos com a ACBC em substituição parcial ao agregado miúdo. As amostras de areia de cinza foram coletadas em usina do Estado de São Paulo, e padronizadas através de um peneiramento manual e moagem. A ACBC utilizada foi caracterizada quanto a sua composição química, granulometria, material pulverulento, massas específica e unitária e absorção. Foram produzidos argamassas e concretos com teores de substituição de 0% (referência), 30% e 50% de ACBC. Nas argamassas, foram realizados testes de resistência à compressão, porosidade (índice de vazios e análise dos poros por microscopia óptica), absorção de água, carbonatação acelerada, penetração de cloretos e condutividade elétrica da solução aquosa dos poros. Os concretos foram submetidos a ensaios de resistência mecânica, índice de vazios, absorção, penetração de cloretos, potencial e taxa de corrosão das armaduras. Desta forma, os resultados indicaram que a substituição em 30% e 50% de areia natural pela ACBC pode aumentar a resistência à compressão dos concretos e a resistência ao ataque de cloretos, e diminuir a probabilidade de despassivação da armadura. Entretanto, com o teor de 50% de ACBC, a taxa de corrosão foi significativamente maior em relação às demais amostras e manteve-se similar entre o concreto com 30% de ACBC e o de referência. Com isso, foi possível concluir que os concretos com 30% de substituição ao agregado miúdo convencional pela ACBC podem ser aplicados em elementos estruturais sem perda de desempenho mecânico e de durabilidade.

The thesis focuses on issues of the procedures in the terminal manoeuvring area (TMA) at regional airports. The goal is to provide a complex study of possible implementation of instrumental arrivals, departures and approaches on the basis of the requirements of the Performance Based Navigation (PBN) at a particular regional airport in the Czech Republic (Kunovice airport). The simulative evaluation of the operational impacts caused by the suggested changes in TMA Brno and CTR Kunovice is also a part of the thesis. The last section is focused on providing a generic methodology describing the process of design and evaluation of PBN procedures.

This study sought to enrich the research in cross-border strategic brand alliance (SBA), an international business practice highly utilized today. In order to spread out the risk of competing in international markets, firms formed alliances with overseas counterparts. However, confusing positioning and inaccuracies in communication in cross-cultural settings reduced the success rate of these partnerships. The content analysis examined cross-border SBA advertisements to shed light on their communicational strategies. Taiwan and the US, representative of inherent cultural values in Eastern and Western countries, served as great research subjects for this comparative study. The findings suggested that cross-border SBA advertisements do not have significantly distinctive communication strategies except for the inherent difference in multi-national characteristics. However, cross-border SBA advertisements in both countries differ from generic advertisements documented in previous studies in terms of information cues, advertising appeals, and general communication strategies. The comparison between cross-border SBA advertisements was reflective of the cultural differences in these cultural contexts. In sum, cross-border SBA advertisements were embedded with stronger cultural distinctiveness and in need of special execution to integrate proper messages. / text

Satellites have revolutionized navigation by making it more universal, accessible and ac- curate. Global Positioning System (GPS) is the most widely used satellite navigation system in the world. However, it is prone to errors from various sources such as the ionosphere, troposphere and clock biases. In order to make the system very accurate and reliable, especially to meet the requirements of safety-critical applications, Satellite Based Augmentation Systems (SBAS) have recently been designed in various countries to augment the GPS by providing corrections for its errors. An Indian SBAS called GAGAN (GPS Aided Geo Augmented Navigation), developed for the Airports Authority of India (AAI) by Indian Space Research Organization (ISRO) is currently being installed and proven for aviation and other use. The uncertain propagation delay of signals through the ionosphere is the most important contributor of error in GPS positioning, its maximal elimination is a major task of SBAS overlays. Ionospheric delays have steady, cyclic, and irregular components. The last types are of particular concern because they are unpredictable. This thesis deals with ionospheric depletion, an important phenomenon of this class that is specific to tropical regions like India and hence have not been well studied in the context of other SBAS systems of the world which cover mid-latitude domains. Depletion is an ionospheric phenomenon in which the density of electrons dips suddenly and then returns close to the previous value. It poses a challenge to the model adopted for ionospheric delay estimation since it may not be detectable by ground systems be- cause of its localized nature, and its occurrence and intensity cannot be predicted. In this work we have analyzed the depletion characteristics over the Indian region such as its distribution, frequency of occurrence, and depth and duration parameters. We have then studied and implemented an existing algorithm to detect a depletion from the Total Electron Content (TEC) data. This algorithm has been found to be inaccurate for estimation of depletion duration, and we have proposed an improved algorithm for depletion detection and shown it to be more suitable for the Indian SBAS, GAGAN. The algorithm utilizes multiple thresholds for depletion detection in order to improve performance in the presence of irregularities including noise. These thresholds are determined by analyzing real TEC data containing depletion events over the Indian region. The detected depletion events are those that have a strong likelihood of contributing large range errors and degrading GAGAN's reliability. The thresholds include depletion parameters such as the depth, duration, rate of change of TEC, and the rate of change of slope of the TEC curve. The characterization of depletion events over the Indian region yielded useful insights into the behaviour of the phenomenon. It was observed that the depletion events were invariably present post-sunset, between 1900 and 0200 hrs. This observation is consistent with the other studies on plasma bubbles so far. The average depth of the depletion was found to be about 3.31 meters of propagation delay while the strongest depletion corresponds to about 5.04 meters of delay. The latter observation impresses upon the need to detect and study the phenomenon of depletion since it is capable of causing a significant loss of accuracy and reliability to the system. The duration of the depletion was found to range from about 10 min to 2.35 hours. In addition, a statistical study of the relationship among the different parameters and a study devoted to now-casting of depletion was made to get a more quantitative insight into the phenomenon of depletion. Scintillation is another phenomenon occurring in the ionosphere which causes rapid fluctuations of phase and amplitude of the signal due to TEC variations in the ionosphere. The occurrences of depletion were observed to be accompanied by scintillation, as also noted in previous studies. The correlation of depletion and scintillation was studied using the data available for this research. A spatial characterization of the depletion events was also investigated using the same temporal TEC data from neighbouring stations which were relatively close to each other. This study addressed the movement of the plasma bubble with respect to the advection speed and direction with definite results. Attention was also devoted to the spatial dimension of the bubble as observed from various stations. Contributions to this variability in the apparent spatial extent comes from the observation of the depletion event from varying lines-of-sight corresponding to different GPS satellites which are also moving, and the differential `slicing' effect because of the location of the stations with respect to the plasma bubble, in addition to the evolution of the bubble during transit. The detection of depletion and its temporal characterization, in addition to the knowledge of its spatial extent and motion, can provide very useful insights on the behaviour of a depletion event and over the ionosphere in general. This knowledge and the mechanism for detection can help to improve the quality and dependability of the information provided by SBAS systems, in particular the Indian GAGAN system, for improved navigation in this part of the world. The present thesis aims to make a significant contribution in this direction.

LPV approaches are being published in the Czech Republic nowadays. Their usage is enabled by the EGNOS European satellite augmentation system. However, published decision heights do not allow equivalence with the ILS CAT I precision approach yet. This work presents the model of automated control of aircraft precision approach. Verification of its functionality shows that applicable airspace requirements can be fulfilled for lower values of decision heights than values already published. The model is developed using contemporary methods of model-based development in the tool supporting common processing of both continuous and discrete signals. Although model architecture follows the structure of commonly used ILS system in definition of coordinate system and in establishing control in two separate directions it allows curved approach. Usage of digital navigation data provided by satellite system opens further opportunities in its usage, expansion and improvements. Model functionality in control of flight course, position and height control is verified in the scenarios covering detailed thesis goals. The goals were defined based on definition of precision approach process and include navigation signal drop-out, impact of wind, various flight path angles and curved approach. Analysis of behavior of controlled aircraft dynamics was a stimulator for research of specific system modules up to the application level, i.e. specific simulations of successful precision approaches.