Coastal erosion can be described as the landward or seaward propagation of coastlines. Coastal processes occur over various space and time scales, limiting in-situ approaches of monitoring change. As such it is imperative to take advantage of multisensory, multi-scale and multi-temporal modern spatial technologies for multi-dimensional coastline change monitoring. The research presented here intends to showcase the synergy amongst remote sensing techniques by showcasing the use of coastal indicators towards shoreline assessment over the Kommetjie and Milnerton areas along the Cape Town coastline. There has been little progress in coastal studies in the Western Cape that encompass the diverse and dynamic aspects of coastal environments and in particular, sediment movement. Cape Town, in particular; is socioeconomically diverse and spatially segregated, with heavy dependence on its 240km of coastline. It faces sea level rise intensified by real-estate development close to the high-water mark and on reclaimed land. Spectral indices and classification techniques are explored to accommodate the complex bio-optical properties of coastal zones. This allows for the segmentation of land and ocean components to extract shorelines from multispectral Landsat imagery for a long term (1991-2021) shoreline assessment. The DSAS tool used these extracted shorelines to quantify shoreline change and was able to determine an overall averaged erosional rate of 2.56m/yr. for Kommetjie and 2.35m/yr. for Milnerton. Beach elevation modelling was also included to evaluate short term (2016-2021) sediment volumetric changes by applying Differential Interferometry to Sentinel-1 SLC data and the Waterline method through a combination of Sentinel -1 GRD and tide gauge data. The accuracy, validation and correction of these elevation models was conducted at the pixel level by comparison to an in-field RTK GPS survey used to capture the current state of the beaches. The results depict a sediment deficit in Kommetjie whilst accretion is prevalent along the Milnerton coastline. Shoreline propagation and coastal erosion quantification leads to a better understanding of geomorphology, hydrodynamic and land use influences on coastlines. This further informs climate adaptation strategies, urban planning and can support further development of interactive coastal information systems.

CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel Superior / The coastline is a dynamic environment and its constant morphodynamic adjustments resulting from natural and human processes. The municipality of Icapuà is situated at the eastern end of the state of Cearà - Brazil, has approximately 45 km of coastline and is one of the most complex environmental systems of CearÃ, with varying morphologies of Quaternary origin, which are preserved stretches and impacts of human actions. The main objective of this research is to analyze the evolution timeline (1987-2014) of the coastline of IcapuÃ, analyzing in an integrated manner the local coastal dynamics. The research was conducted in five main stages: bibliographic and cartographic survey, field work, preparation and database analysis in GIS, the diagnosis of evolution with the development of cartographic products and projection scenarios. The coastal plain was compartmentalized into three sectors studies (west, central and east) and used four mathematical and statistical procedures extension "Digital Shoreline Analysis System 4.3" (DSAS) for ArcGIS 10.1, which allowed to compare the shorelines multitemporal extracted from remote sensors products through a base line and transects spaced 500 m apart. It was possible to estimate in meters, considering the clip timeline, the maximum variation (NSM), the absolute variation (SCE), the mean annual change (EPR) and annual linear regression trend (LRR). Assigns to the coastline five classes according to the processes identified in the sections, as follows: progradation continuous, mo*derate progradation and / or semi-relative stability, moderate erosion and / or semi-continuous and continuous erosion. It was evident that the most relevant progradational and erosive processes are present in the western sectors, subsectors erosion Retiro Grande, Redonda and Peroba with trends of -0.5 to -4 m / year, and central sectors with significant decreases in Barreiras da Sereia subsectors and Barrinha, that a decline of up to 115 meters in 27 years and trends between -1.2 and -4.5 m / year, with varying social and environmental impacts, while the eastern sector showed relative stability. From this, it was possible to discuss containment strategies erosion, project possible evolutionary scenarios and suggest directions for planning and management of the coastal zone of the municipality. / A linha de costa à um ambiente dinÃmico e os seus constantes ajustes morfodinÃmicos resultam de processos naturais e humanos. O MunicÃpio de Icapuà està localizado no extremo leste do Estado do Cearà - Brasil, possui aproximadamente 45 km de linha de costa e representa um dos mais complexos sistemas ambientais do litoral cearense, com variadas morfologias de origem QuaternÃria, trechos relativamente conservados e impactos decorrentes das aÃÃes humanas. O objetivo principal desta pesquisa à analisar a evoluÃÃo espaÃotemporal (1987-2014) da linha de costa de IcapuÃ, considerando de forma integrada a dinÃmica costeira local. A pesquisa foi realizada em cinco etapas principais: o levantamento bibliogrÃfico e cartogrÃfico, os trabalhos de campo, a elaboraÃÃo e anÃlise de banco de dados em SIG, o diagnÃstico da evoluÃÃo com a elaboraÃÃo de produtos cartogrÃficos e a projeÃÃo de cenÃrios. Segmentou-se a planÃcie litorÃnea em trÃs setores de estudos (oeste, central e leste) e foram aplicados quatro procedimentos matemÃticos e estatÃsticos da extensÃo Digital Shoreline Analysis System 4.3 (DSAS) para o ArcGIS 10.1, que permitiram comparar as linhas de costa multitemporais extraÃdas de produtos sensores remotos por meio de uma linha de base e transectos espaÃados em 500 metros entre si. Possibilitou-se estimar em metros, considerando o recorte espaÃotemporal, a variaÃÃo mÃxima (NSM), a variaÃÃo absoluta (SCE), a mÃdia de variaÃÃo anual (EPR) e a tendÃncia anual de regressÃo linear (LRR). AtribuÃram-se à linha de costa cinco classes conforme os processos identificados nos trechos, sendo eles: progradaÃÃo contÃnua, progradaÃÃo moderada e/ou semicontÃnua, relativa estabilidade, erosÃo moderada e/ou semicontÃnua e erosÃo contÃnua. Evidenciou-se que os processos progradacionais e erosivos mais relevantes se encontram nos setores oeste, com erosÃo nos subsetores Retiro Grande, Redonda e Peroba, com tendÃncias de -0,5 a -4 m/ano, e central com recuos significativos nos subsetores Barreiras da Sereia e Barrinha, essa com recuo de atà 115 metros em 27 anos e tendÃncias entre -1,2 e -4,5 m/ano, desencadeando variados impactos socioambientais, enquanto o setor leste denotou relativa estabilidade. Com suporte nisso, foi possÃvel discutir as estratÃgias de contenÃÃo da erosÃo, projetar possÃveis cenÃrios evolutivos e sugerir direcionamentos para o planejamento e a gestÃo da zona costeira do municÃpio.

SOUZA, Wallason Farias de. Sensoriamento remoto e SIG aplicados à análise da evolução espaçotemporal da linha de costa do município de Icapuí, Ceará - Brasil. 2016. 134 f. Dissertação (Mestrado em geografia)- Universidade Federal do Ceará, Fortaleza-CE, 2016. / Submitted by Elineudson Ribeiro (elineudsonr@gmail.com) on 2016-07-28T18:58:35Z No. of bitstreams: 1 2016_dis_wfsouza.pdf: 8761338 bytes, checksum: ec4e7460c4dcaa9fcbf283e5c60a97fe (MD5) / Approved for entry into archive by José Jairo Viana de Sousa (jairo@ufc.br) on 2016-08-02T14:23:50Z (GMT) No. of bitstreams: 1 2016_dis_wfsouza.pdf: 8761338 bytes, checksum: ec4e7460c4dcaa9fcbf283e5c60a97fe (MD5) / Made available in DSpace on 2016-08-02T14:23:50Z (GMT). No. of bitstreams: 1 2016_dis_wfsouza.pdf: 8761338 bytes, checksum: ec4e7460c4dcaa9fcbf283e5c60a97fe (MD5) Previous issue date: 2016 / The coastline is a dynamic environment and its constant morphodynamic adjustments resulting from natural and human processes. The municipality of Icapuí is situated at the eastern end of the state of Ceará - Brazil, has approximately 45 km of coastline and is one of the most complex environmental systems of Ceará, with varying morphologies of Quaternary origin, which are preserved stretches and impacts of human actions. The main objective of this research is to analyze the evolution timeline (1987-2014) of the coastline of Icapuí, analyzing in an integrated manner the local coastal dynamics. The research was conducted in five main stages: bibliographic and cartographic survey, field work, preparation and database analysis in GIS, the diagnosis of evolution with the development of cartographic products and projection scenarios. The coastal plain was compartmentalized into three sectors studies (west, central and east) and used four mathematical and statistical procedures extension "Digital Shoreline Analysis System 4.3" (DSAS) for ArcGIS 10.1, which allowed to compare the shorelines multitemporal extracted from remote sensors products through a base line and transects spaced 500 m apart. It was possible to estimate in meters, considering the clip timeline, the maximum variation (NSM), the absolute variation (SCE), the mean annual change (EPR) and annual linear regression trend (LRR). Assigns to the coastline five classes according to the processes identified in the sections, as follows: progradation continuous, mo*derate progradation and / or semi-relative stability, moderate erosion and / or semi-continuous and continuous erosion. It was evident that the most relevant progradational and erosive processes are present in the western sectors, subsectors erosion Retiro Grande, Redonda and Peroba with trends of -0.5 to -4 m / year, and central sectors with significant decreases in Barreiras da Sereia subsectors and Barrinha, that a decline of up to 115 meters in 27 years and trends between -1.2 and -4.5 m / year, with varying social and environmental impacts, while the eastern sector showed relative stability. From this, it was possible to discuss containment strategies erosion, project possible evolutionary scenarios and suggest directions for planning and management of the coastal zone of the municipality. / A linha de costa é um ambiente dinâmico e os seus constantes ajustes morfodinâmicos resultam de processos naturais e humanos. O Município de Icapuí está localizado no extremo leste do Estado do Ceará - Brasil, possui aproximadamente 45 km de linha de costa e representa um dos mais complexos sistemas ambientais do litoral cearense, com variadas morfologias de origem Quaternária, trechos relativamente conservados e impactos decorrentes das ações humanas. O objetivo principal desta pesquisa é analisar a evolução espaçotemporal (1987-2014) da linha de costa de Icapuí, considerando de forma integrada a dinâmica costeira local. A pesquisa foi realizada em cinco etapas principais: o levantamento bibliográfico e cartográfico, os trabalhos de campo, a elaboração e análise de banco de dados em SIG, o diagnóstico da evolução com a elaboração de produtos cartográficos e a projeção de cenários. Segmentou-se a planície litorânea em três setores de estudos (oeste, central e leste) e foram aplicados quatro procedimentos matemáticos e estatísticos da extensão Digital Shoreline Analysis System 4.3 (DSAS) para o ArcGIS 10.1, que permitiram comparar as linhas de costa multitemporais extraídas de produtos sensores remotos por meio de uma linha de base e transectos espaçados em 500 metros entre si. Possibilitou-se estimar em metros, considerando o recorte espaçotemporal, a variação máxima (NSM), a variação absoluta (SCE), a média de variação anual (EPR) e a tendência anual de regressão linear (LRR). Atribuíram-se à linha de costa cinco classes conforme os processos identificados nos trechos, sendo eles: progradação contínua, progradação moderada e/ou semicontínua, relativa estabilidade, erosão moderada e/ou semicontínua e erosão contínua. Evidenciou-se que os processos progradacionais e erosivos mais relevantes se encontram nos setores oeste, com erosão nos subsetores Retiro Grande, Redonda e Peroba, com tendências de -0,5 a -4 m/ano, e central com recuos significativos nos subsetores Barreiras da Sereia e Barrinha, essa com recuo de até 115 metros em 27 anos e tendências entre -1,2 e -4,5 m/ano, desencadeando variados impactos socioambientais, enquanto o setor leste denotou relativa estabilidade. Com suporte nisso, foi possível discutir as estratégias de contenção da erosão, projetar possíveis cenários evolutivos e sugerir direcionamentos para o planejamento e a gestão da zona costeira do município.

La tomographie d'émission par positrons (TEP) se distingue des autres modalités d'imagerie par sa capacité à localiser et quantifier la présence de molécules marquées, appelées radiotraceurs, au sein d'un organisme. Cette capacité à mesurer l'activité biologique des différents tissus d'un sujet apporte des informations uniques et essentielles à l'étude de tumeurs cancéreuses, au fonctionnement du cerveau et de ses maladies neurodégénératives et de la pharmacodynamique de nouveaux médicaments. Depuis les tout débuts de la TEP, les scientifiques rêvent de pouvoir utiliser l'information de temps de vol des photons pour améliorer la qualité de l'image TEP. L'arrivée des photodiodes avalanche monophotoniques (PAMP), rend maintenant ce rêve possible. Ces dispositifs détectent la faible émission de lumière des scintillateurs et présentent une réponse grandement amplifiée avec une faible incertitude temporelle. Mais le potentiel des PAMP n'est pas encore entièrement exploré. Plutôt que de faire la somme des courants d'une matrice de PAMP, il est possible d'utiliser leur nature intrinsèquement binaire afin de réaliser un photodétecteur numérique capable de déterminer avec précision le temps d'arrivée de chaque photon de scintillation. Toutefois, la conception de matrices de PAMP numériques en est encore à ses débuts, et les outils de conception se font rares. Ce projet de doctorat propose un simulateur facilitant la conception de matrices de PAMP, que celles-ci soient analogiques ou numériques. Avec cet outil, l'optimisation d'une matrice de PAMP numérique basée dans une technologie Teledyne DALSA HV CMOS \SI{0,8}{\micro\metre} est proposée. En plus de guider les choix de conception de l'équipe, cette optimisation permet de mieux comprendre quels paramètres influencent les performances du détecteur. De plus, puisque le photodétecteur n'est pas l'unique acteur des performances d'un détecteur TEP, une étude sur l'impact des scintillateurs est aussi présentée. Cette étude vérifie l'amélioration apportée par l'intégration de photons prompts dans des scintillateurs LYSO. Enfin, une approche novatrice pour discriminer l'énergie des évènements TEP basée sur l'information temporelle des photons de scintillation a été développée et vérifiée à l'aide du simulateur. Bien que ce simulateur et les études réalisées dans le cadre de cette thèse soient concentrés sur des détecteurs TEP, l'utilité des PAMP et du simulateur ne se limite pas à cette application. Les matrices de PAMP sont prisées pour le développement de détecteur en physique des particules, physique nucléaire, informatique quantique, LIDAR et bien d'autres. / Abstract : Positron emission tomography (PET) stands out among other imaging modalities by its ability to locate and quantify the presence of marked molecules, called radiotracers, within an organism. The capacity to measure biological activity of various organic tissues provides unique information, essential to the study of cancerous tumors, brain functions and the pharmacodynamics of new medications. Since the very beginings of PET, scientists dreamed of using the photon's time-of-flight information to improve PET images. With the recent progress of Single Photon Avalanche Diodes (SPAD), this dream is now possible. These photodetectors detect the scintillators' low light emission and offers a greatly amplified response with only a small time uncertainty. However the potential of SPAD has not yet been entirely explored. Instead of summing the currents of a SPAD array, it is possible to use their intrinsically binary operation to build a digital photodetector, able to establish with precision the time of arrival of each scintillation photon. With this information, the time-of-flight measurements will be much more precise. Yet the design of digital SPAD arrays is in its infancy and design tools for this purpose are rare. This project proposes a simulator to aid the design of SPAD arrays, both analog and digital. With this tool, we propose an optimised design for a digital SPAD array fabricated in Teledyne Dalsa HV CMOS \SI{0.8}{\micro\metre} technology. In addition to guiding the design choices of our team, this optimisation led to a better understanding which parameters influence the performance of a PET detector. In addition, since the photodetector is not the sole actor in the performance of a PET detector, a study on the effect of scintillators is also presented. This study evaluates the improvement brought by incorporating a prompt photon emission mechanism in LYSO crystals. Finally, we describe a novel approach to energy discrimination based on the timing information of scintillation photons was developped and tested using the simulator. While this simulator and the studies presented in this thesis focus on PET detectors, SPAD are not limited to this sole application. SPAD arrays are promising for a wide variety of fields, including particle physics, high energy physics, quantum computing, LIDAR and many more.