La miniaturisation des systèmes optiques est un domaine de recherche qui suscite un grand intérêt scientifique actuellement. En effet, moins volumineux et moins chers, ils peuvent prétendre à être diffusés dans des applications diverses. L'objectif de cette thèse est de concevoir des systèmes d'imagerie extrêmement compacts, intégrés au plus près du détecteur infrarouge refroidi, et idéalement solidaires de celui-ci. Des travaux de recherche sont actuellement menés pour miniaturiser les systèmes optiques : moins volumineux et moins chers, ils peuvent prétendre à être diffusés dans des applications diverses. L'objectif de cette thèse est de concevoir des systèmes d'imagerie extrêmement compacts, intégrés au plus près du détecteur infrarouge refroidi, et idéalement solidaires de celui-ci. J'ai tout d'abord mis en évidence des stratégies pour la simplification et la miniaturisation des systèmes optiques. Parmi elles, les approches menant à des systèmes multivoies semblent être les plus prometteuses pour concevoir des systèmes à la fois compacts et performants. J'ai alors proposé deux architectures multivoies simples, compactes et intégrées au plus près du détecteur infrarouge. La première, de champ d'observation égal à 120°, intègre une matrice de microlentilles à quelques centaines de micromètres seulement du détecteur infrarouge : elle est qualifiée de caméra sur puce. Des défis technologiques ont dû être relevés pour réaliser ce composant. J'ai développé un algorithme de reconstruction d'images et évalué expérimentalement les performances de la caméra. Ce système produit, après traitements, une image échantillonnée au pas de 7,5 µm. Cette valeur est deux fois meilleure que celle qui pourrait être obtenue avec une caméra monovoie classique, associée à un détecteur infrarouge à l'état de l'art actuel, avec un pas pixel de 15 µm. J'ai contribué à la réalisation du second système en développant une méthode originale et simple pour en fabriquer les matrices de microlentilles. Cette technique consiste à mouler par compression de la poudre de bromure de potassium à température ambiante.Ces travaux ouvrent la voie à une nouvelle génération de détecteurs infrarouges, qui intègrent une fonction d'imagerie. / Miniaturizing optical systems is a research area of great interest nowadays: if they were smaller and cheaper, optical systems could be widespread in many applications. This work aims at designing very compact optical systems for imagery applications, which could be integrated near the infrared cryogenic detector and ideally directly on it.First, I have presented original design strategies to simplify and miniaturize optical systems. Approaches which lead to multichannel systems seem to be the most interesting ones to design compact and effective systems. Then, I have proposed two multichannel optical architectures, which are simple, compact, and integrated near the infrared detector. The first camera, which has a field of view equal to 120°, integrates a microlens array at a few hundreds of micrometers only of the infrared detector: it is called a wafer-level camera. Technological challenges have been overcome to manufacture this component. I have developed an image processing method, and assessed the characteristics of the camera experimentally. This system samples the final image with a pitch equal to 7,5 µm. This value is two times better than the one which could be obtained by using a one-channel camera associated with a state-of-the-art infrared detector, with a pixel pitch equal to 15 µm. In order to manufacture the second architecture, I have developed an original and simple method to obtain the microlens arrays, by compression molding of Potassium Bromide powder at ambient temperature. This work gives some elements to design a new generation of infrared detectors with an imagery function.

This study seeks to prove the usefulness of the Multichannel Analysis of Surface Waves (MASW) method as complementary data to conventional geotechnical and geological data in the characterization of areas of landslide risk. The setting is located in a low income housing neighborhood in the city of Campos do Jordão, state of São Paulo, Brazil. The area was devastated by numerous landslides between December 1999 to January 2000 after heavy rainfall in the area. The landslides in this area are known to be shallow. Refraction and MASW surveys were performed in this research and then processed to obtain seismic velocity profiles of the subsurface. In order to better identify the fundamental mode of the Rayleigh wave, separate surveys isolating the vertical and radial components of the Rayleigh wave were performed. By comparing the inverted shear wave ( ) and compressional wave ( ) profiles with the already known geotechnical and geological data of the site, a better understanding of the geological interfaces that constitute the landslide prone area is obtained. / Este estudo busca demonstrar a aplicabilidade do método de análise multicanal de ondas superficiais (MASW) e a importância da integração de seus resultados com os da investigação geológica-geotécnica para a caracterização de áreas sujeitas a deslizamentos de terra. O local de estudo situa-se em uma área residencial com precárias condições de infraestrutura urbana na cidade de Campos do Jordão, estado de São Paulo, Brasil. Na área houve vários episódios de escorregamento entre dezembro de 1999 e janeiro de 2000 após a ocorrência de chuvas intensas. Os escorregamentos nesta área são classificados como rasos. Nesta pesquisa foram realizados ensaios de sísmica de refração e MASW e gerados perfis e seções de velocidade de propagação das ondas sísmicas. Para obter uma melhor identificação do modo fundamental da onda Rayleigh foram realizadas diferentes aquisições visando ao registro das componentes vertical e radial do movimento da onda. A integração dos perfis de velocidades da onda cisalhante (VS) e da onda compressional (VP) com os dados geológicos e geotécnicos obtidos anteriormente permitiu aprimorar o mapeamento das interfaces geológicas importantes para o estudo dos processos de escorregamento do local.

This study seeks to prove the usefulness of the Multichannel Analysis of Surface Waves (MASW) method as complementary data to conventional geotechnical and geological data in the characterization of areas of landslide risk. The setting is located in a low income housing neighborhood in the city of Campos do Jordão, state of São Paulo, Brazil. The area was devastated by numerous landslides between December 1999 to January 2000 after heavy rainfall in the area. The landslides in this area are known to be shallow. Refraction and MASW surveys were performed in this research and then processed to obtain seismic velocity profiles of the subsurface. In order to better identify the fundamental mode of the Rayleigh wave, separate surveys isolating the vertical and radial components of the Rayleigh wave were performed. By comparing the inverted shear wave ( ) and compressional wave ( ) profiles with the already known geotechnical and geological data of the site, a better understanding of the geological interfaces that constitute the landslide prone area is obtained. / Este estudo busca demonstrar a aplicabilidade do método de análise multicanal de ondas superficiais (MASW) e a importância da integração de seus resultados com os da investigação geológica-geotécnica para a caracterização de áreas sujeitas a deslizamentos de terra. O local de estudo situa-se em uma área residencial com precárias condições de infraestrutura urbana na cidade de Campos do Jordão, estado de São Paulo, Brasil. Na área houve vários episódios de escorregamento entre dezembro de 1999 e janeiro de 2000 após a ocorrência de chuvas intensas. Os escorregamentos nesta área são classificados como rasos. Nesta pesquisa foram realizados ensaios de sísmica de refração e MASW e gerados perfis e seções de velocidade de propagação das ondas sísmicas. Para obter uma melhor identificação do modo fundamental da onda Rayleigh foram realizadas diferentes aquisições visando ao registro das componentes vertical e radial do movimento da onda. A integração dos perfis de velocidades da onda cisalhante (VS) e da onda compressional (VP) com os dados geológicos e geotécnicos obtidos anteriormente permitiu aprimorar o mapeamento das interfaces geológicas importantes para o estudo dos processos de escorregamento do local.

Den fysiska handelsplatsen har länge varit kärnan inom handeln men utmanas nu av den växande e-handeln. Statistik från HUI Research och Svensk Handel visar att e-handeln i Sverige har haft en stark tillväxt de senaste åren som beräknas fortsätta öka. Men vad innebär egentligen den ökande e-handeln för fysiska handelsplatser? Genom media får vi bilden av att konsekvenserna av en ökad e-handel resulterar i en butiksdöd. En mängd forskare menar att konsekvenserna snarare är en ökad integrering av e-handel och fysisk handel. Vi genomförde tidigt en förstudie som visade att det finns en avsaknad av ett empiriskt synsätt i diskussionen kring vad den ökande e-handeln innebär för fysiska handelsplatser. Syftet med studien blev således att komplettera nuvarande forskning genom en kvalitativ studie som applicerar ett empiriskt synsätt och undersöker vad den ökande e-handeln innebär för fysiska handelsplatser. Det gjorde vi genom att intervjua fastighetsägare och handelsaktörer inom detaljhandeln. Studiens resultat visar att det finns skäl till att tro att de fysiska handelsplatserna kommer påverkas ju mer e-handeln växer. Den digitala- och fysiska handeln kommer att integreras ännu mer och fastighetsägares strategier förändras för att se till att deras handelsplatser förblir attraktiva när e-handeln ökar. / Since way back the physical retail location has been the core of retail, however it is now challenged by the emerging e-commerce. Statistics from HUI Research and the Swedish Trade Federation show that e-commerce in Sweden has experienced strong growth in recent years and is expected to rapidly increase and transform the physical retail landscape. But what does the growing e-commerce really mean for the physical stores? From what media cover in the news we get the impression that the consequences of increased e-commerce result in a death of physical retail stores. A number of researchers argue that the consequences are instead rather an increased integration of e-commerce and commerce in physical stores. From the pre-study we conducted there was an indication that the discussion of what the increasing e-commerce entails for the physical stores lacks an approach consisting of an empirical perspective. The purpose of the study was thus to supplement current research through a qualitative study that applies an empirical approach and investigates what the increasing e-commerce entails for the physical stores. We did this by interviewing real estate property owners and retail players within the retail sector. The result of the study shows that there is reason to believe that the physical stores will be affected the more the e-commerce grows. Digital and physical commerce will be integrated even more, and property owners' strategies change to ensure that their real estate remain attractive when e-commerce grows rapidly and the market transforms.

The East African coastal basin of Tanzania, which is characterised by an extensional tectonic style, is located along the passive continental margin of the western Indian Ocean. The present study is concerned with the Mafia Island and the Mafia Channel which together form a subbasin within the north-south elongated coastal sedimentary basin of Tanzania. In the time interval from late Paleozoic to Recent, the passive margin of the region was subjected to a three-fold geological development, namely the Karoo rifting phase (1) which is characterised by extensional tectonics, the Gondwana break-up and opening of the Somali basin (2) which was contemporaneous with the movement of Madagascar off the east African coast in the Mesozoic, and the Cenozoic East African rift system (3). This structural framework made provision to the basin deposition history. The development started with the deposition of the continental, terrigenous, Karoo sequence in the Upper Permian to Lower Jurassic. The Karoo deposition was followed by a series of transgressions and regressions under full marine conditions which started in the Middle Jurassic and continued into the Tertiary. The deposits include marine marls, detrital limestones, fossiliferous shales and calcareous sandstones, reaching in places thicknesses of more than 4000 m of Mesozoic, and more than 6000 m of Cenozoic, sediments. Seismostratigraphic techniques applied in the Mafia Channel and Island identified five deposition sequences separated by regional unconformity surfaces i.e. sequence boundaries. Including the pre-Upper Cretaceous sequence they are; the Upper Cretaceous to Middle Eocene sequence (DS I), the Middle Eocene to Lower Miocene sequence (DS II), the Lower Miocene to Pliocene sequence (DS III), and the Pliocene to Recent sequence (DS IV). In the Mafia Channel up to 6000 m of sediments are present. Their ages range from Middle Eocene to Quaternary. The deposits start with marine shales which are overlain by carbonate rocks of Upper Eocene . These carbonates are in the present investigation regarded as the acoustic basement in the central and northern parts of the study area. On top of Upper Eocene carbonates, deltaic and shallow marine sediments are deposited. Southwards in the Channel, the sequences are located at shallower depths which makes it possible to trace also the Upper Cretaceous sequence with confidence. On the Mafia Island, the deposition on top of the Upper Cretaceous (Campanian) acoustic basement mainly includes deltaic sandstones, followed by intercalations of carbonate and argillaceous rocks. The structural framework reflects the different tectonic regimes which prevailed in the area. Above the acoustic basement structural elements of Mafia Channel and Island are interpreted as originating from the superimposition of the Cenozoic East African rifting event, and from the uplifts of the mainland coast and Mafia Island during Late Eocene time. As a result the central part collapsed and formed an asymmetric sag structure in the channel. These elements are seismically identified and subdivided as (from northwest to southeast), the Dar-es-Salaam Platform Offshore, the Central Mafia Channel and the Mafia Island Rise. These domains are separated by respective NE-SW major faults (MF1, MF2 and MF3) and can be demonstrated in the profiles which run in a NW-SE direction. With respect to petroleum potential, the Mafia Channel and Island indicate a considerable content. Three hydrocarbon plays are introduced, namely; 1) the Neocomian regressive sands of Songosongo play 2) the Upper Eocene limestone and 3) the Upper Oligocene turbidites.

El problema de detección de series temporales multivariadas surge en aplicaciones tan dispares como radar, sonar, ingeniería biomédica o comunicaciones. Aunque, sin lugar a dudas, dos de las aplicaciones más importantes en la actualidad son el sensado espectral multiantena para radio cognitiva (CR) y las redes de sensores. En el primer caso, el objetivo consiste en detectar bandas del espectro vacías, para permitir la transmisión oportunista de usuarios secundarios. En el segundo, a partir de las señales adquiridas por un conjunto de sensores, se quiere determinar qué modelo ha generado dichas observaciones. Los problemas de detección multicanal se pueden resolver de diferentes maneras en función de la información a priori disponible. En concreto, en esta Tesis se consideran los detectores basados en la estructura espacial, que es una característica especialmente interesante dado que permite desarrollar tests que necesitan muy poca información a priori sobre las señales. / The multiple-channel signal detection problem appears in many applications, such as radar and sonar, bioengineering, or communications. Nevertheless, two of the most important applications nowadays are multiantenna spectrum sensing and sensor networks. In the first case, we must detect frequency sub-bands which are not occupied, to allow the opportunistic transmission of secondary users. In the second case, the goal consists in determining, from a set of observations, the model which better explains the data. Multiple-channel detection problems may be solved following different approaches depending on the available information. Concretely, in this Thesis, spatial-structure based detectors are considered, providing tests that use no or very limited a priori information about the signal to be detected.

Orientadores: Márcio Texeira do Nascimento Varella, Marco Aurélio Pinheiro Lima / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Fisica Gleb Wataghin / Made available in DSpace on 2018-08-15T19:40:36Z (GMT). No. of bitstreams: 1 Oliveira_ElianeMarquesde_D.pdf: 3873197 bytes, checksum: a3679517ca8a236b550f4e76c004b642 (MD5) Previous issue date: 2010 / Resumo: O Método Multicanal de Schwinger (SMC) foi utilizado para estudar o espalhamento de elétrons e pósitrons de baixa energia por moléculas de pirrol (C4H4NH) e propanol (C3H7OH), para o primeiro caso, e acetileno (C2H2) e monóxido de carbono (CO), para o último caso. Seções de choque elásticas integrais e diferenciais foram calculadas para todos os sistemas, exceto para colisões pósitron-acetileno. Neste caso, utilizando o SMC combinado com o Formalismo dos Operadores de Projeção de Feshbach, seções de choque vibracionalmente resolvidas e o parâmetro de aniquilação (Zeff) foram calculados para a transição 0--> 1. No que se refere ao espalhamento de elétrons, as seções de choque integrais (ICS) calculadas para moléculas de pirrol indicam a formação de ressonâncias * (não dissociativas) e ? * (dissociativas), as quais podem dar origem a mecanismos de dissociação indireta e direta. Sendo assim, o pirrol é um protótipo adequado para o entendimento dos detalhes acerca de danos causados no DNA por elétrons de baixa energia. Já as ICS's obtidas para moléculas de propanol estão em bom acordo com os resultados teóricos e experimentais disponíveis na literatura. Para colisões de pósitrons, os resultados obtidos para moléculas de acetileno, para a transição O --> 1 num modelo de onda s, apontam para a formação de um estado virtual o qual torna-se um estado ligado quando as ligações C-C e C- H são deformadas ao longo dos modos normais de estiramento simétrico inativos no infravermelho. Embora pouco representativos, tais modos estão em assina,turas claras no parâmetro de aniquilação. As seções de choque possuem bom acordo com resultados extraídos da literatura. Por outro lado, os modos normais C-H de estiramento assimétrico e bendin,q ativos no infravermelho, por simetria, não contribuem para a seção de choque e parâmetro de aniquilação para a transição O --> 1 num modelo de onda s. Para colisões pósitron-CO, bom acordo foi encontrado entre a seção de choque integral calculada e dados teóricos e experimentais disponíveis na literatura / Abstract: The Schwinger Multichannel Method (SMC) was employed to study scattering of low-energy electrons and positrons by pyrrole (C4H4NH) and propanol (C3H7OH) molecules, for the former, and acetylene (C2H2) and carbon inonoxide (CO), for the latter. Elastic differential and integral cross sections were calculated for alI systems, except for positron-acetylene collisions. In this case, using the SMC combined with the Feshbach Projection Operator approach, vibrationally resolved cross sections and annihilation parameter were obtained for the O --> 1 transition. For electron scattering, the integral cross sections lecules indicate ¶* (non dissociative) and O+* (dissociative) resonances, which can give rise to indirect and direct dissociation mechanisms. In view of this, pyrrole molecules are a suitable prototype for detailed studies of dissociative electron attachment to DNA. For electron-propanol collisions, reasonable agreement was obtained between present and calculated and measured results available in the literature. For positron scattering, the results obtained for acetylene molecules, for the O --> 1 transition and an s-wave model, pointed out a virtual state pole that becomes a bound state as either bond C-C or C-H are stretched along the infrared inactive symmetric modes. Although not significant, these modes have clear assignments in the annihilation parameter. Present cross sections agree very well with calculated results of the literature. On the other hand, the C- H asymmetric and bending infrared active modes, due to the parity of vibrational modes, cannot contribute for cross sections and annihilation parameter for the O --> 1 transition in an s-wave modelo For positron-CO collisions, good agreement was found between present ICS and the measured and calculated results available in the literature / Doutorado / Física Atômica e Molecular / Doutora em Ciências

Shock waves are generally characterized by a sharp change of the pressure, which causes subsequent changes in properties of the surrounding in which it spreads. In medical applications, it is an acoustic shock wave which is used for the treatment of concrements for more than 25 years. This success naturally led to considerations about the possibility of using shock waves in other areas of medicine. One of the main directions of the research is the possibility of the damage to tumor tissue. In contrast to concrements the tumor tissue is not different from surrounding tissues by its acoustic attributes, so the normal lithotryptor is not appropriate for this application. Therefore, there has been developed a new source of shock waves, which is based on the principle of multichannel discharge on the composite anode. The experiments demonstrated the effect of the new source on the acoustically homogeneous tissue of the thigh muscle at a depth of rabbit in vivo. Then there was observed the damage to tumor tissue in vivo in rats. Finally, there was observed the damage to tumor tissue in vivo in rats in the combination with cisplatin and Photosan. It was found that the new source of shock waves can cause the damage to the acoustically homogeneous tissue in vivo in depth. It also can damage the tumor...

Communication underwater is challenging because of the inherent characteristics of the media. First, common radio frequency (RF) signals utilized in wireless communications cannot be used under water. RF signals are attenuated in such as way that RF communication underwater is restricted to very few meters. As a result, acoustic-based communication is utilized for underwater communications; however, acoustic communication has its own limitations. For example, the speed of sound is five orders of magnitude lower than the speed of light, meaning that communications under water experience long propagation delays, even in short distances. Long propagation delays impose strong challenges in the design of Data Link Layer (DLL) protocols. The underwater communication channel is noisy, too. The bit error rate (BER) can also change depending on depth and other factors, and the errors are correlated, like in wireless communications. As in wireless communications, transducers for acoustic communication are half duplex, limiting the application of well-known detection mechanisms in Medium Access Control (MAC) layer protocols. Further, known problems like the hidden and exposed terminal problem also occur here. All these aspects together make the underwater communication channel to have the worst characteristics of all other known channels. Because of these reasons, underwater scenarios are complicated to implement, especially when they have underwater autonomous vehicles exchanging information among them. This dissertation proposes data link layer protocols in support of swarming of underwater autonomous vehicles that deal with the problems mentioned before. At the MAC sublayer, a MAC protocol called 2MAC is introduced. 2MAC improves the throughput of the network using the multichannel capabilities of OFDM at the physical layer. At the logical link control sublayer, a protocol named SW-MER is proposed. SW-MER improves the throughput and the reliability combining the well-known stop and wait protocol with the sliding window strategy, and using an exponential retransmission strategy to deal with errors. 2MAC and SW-MER are evaluated and compared with other protocols using analytical means and simulations. The results show that by using 2MAC, packet collisions are considerably reduced and the throughput improved. In addition, the use of SW-MER improves the packet delivery ratio over existing mechanisms. In general, the evaluations indicate that the proposed data link layer protocols offer a better communication alternative for underwater autonomous vehicles (UAV) than traditional protocols.

This thesis deals with design and implementation of multi-channel audio signal streaming via local network. The aim was to choose suitable processor for the transmission of up to 32 channels of audio signal, which will be used for implementation. Also the low-latency ASIO driver was studied and was used to provide timestamps for synchronization. The transmission protocol was designed for signaling and for the real time stream. The actual transmission is provided by TCP protocol. In conclusion, I created the application for development board with choosen MCU. Finally whole solution was tested with real data.