Este trabalho visa a avaliar os efeitos dinâmicos em vigas esbeltas semi-infinitas com contato unilateral em apoio elástico sob flexão composta, e sua possível aplicação a dutos flexíveis de extração de petróleo offshore em configuração de catenária (Steel Catenary Risers) provocados por esforços de movimento da plataforma. O estudo se desenvolve com formulação de vigas semi-infinitas em duas dimensões (2D) com suporte unilateral elástico, considerando-se inicialmente apenas efeito de flexão, à qual se aplica o método das múltiplas escalas (MME) para obtenção dos modos de vibração, e posteriormente o método das variedades invariantes (MVI) para recuperação das relações modais entre as coordenadas generalizadas e as variáveis modais. Trata-se, a seguir, da formulação do problema com consideração da tração, tanto estática como dinâmica, e a projeção da equação de movimento completa segundo os modos obtidos no problema da flexão simples, para obtenção do modelo de ordem reduzida com efeito de tração, que permitiu estudar este último qualitativa e quantitativamente. A formulação inicial teve como ponto de partida a utilização de mudanças de variáveis que permitiu a transformação do problema de condições móveis em condições fixas de contorno, propiciando caracterizar o movimento vertical da viga na solução analítica do problema de vibrações livres, até o limite possível, para depois utilizar técnicas de integração numérica na solução do problema de vibrações forçadas. A motivação para estudo de tais efeitos está ligada à importância indiscutível que tem para a indústria petrolífera e para a economia mundial, além do crescente papel deste segmento em termos nacionais. A descoberta do Campo de Tupi, na Bacia de Santos, que representa a maior reserva de óleo e gás do País, alavancou pesquisas para extração de petróleo em águas ultra-profundas (profundidades da ordem de 2.500m) (fonte: www.petrobras.com.br), além da necessidade já estabelecida de maiores pesquisas em águas profundas (profundidades que podem chegar a 2.000m). Considere-se também a motivação da própria Petrobrás, cujo intuito é ter capacidade de extrair 4,5 milhões de barris por dia até 2020. Tal capacidade de produção deve exigir 45 sistemas de produção, sendo que cada sistema de produção necessita de 4 a 5 barcos de apoio, totalizando assim 200 barcos operando em 2020 (Fonte: O Estado de São Paulo, Ano 131, Nº 42786, Coluna Celso Ming). Apesar da crescente pesquisa em fontes alternativas de energia, a demanda não só por óleo e gás, mas também pela utilização de polímeros e componentes plásticos, ainda sustentará a extração de petróleo por no mínimo algumas décadas. Além disso, técnicas melhores na fixação de carbono (técnicas naturais e artificiais para seqüestro de carbono), permitem sonhar que a utilização de petróleo, desde a sua queima até a produção de material sintético possa se tornar cada vez menos impactante para o meio ambiente. / This work aims at analyzing the dynamical effects in slender reticulated beams on elastic support with unilateral contact under combined axial force and bending, and the possibility of its association with steel catenary risers connected to offshore structures, caused by movement of the platform. The study is developed based on 2D semi-infinite beams on unilateral elastic support, initially considering only bending effects, to which the multiple scales method (MSM) is applied to obtain vibration modes, and thereafter the invariant manifold method (IMM) to obtain the modal relationships between the generalized coordinates and the modal variables. It follows the formulation of the problem considering tension effects, both from static and dynamical sources, and the projection of the full equation of motion with respect to the vibration modes from the first formulation considering only bending effects, which allows us to obtain the reduced order model with tension effects, and its application to steel catenary risers (SCR). The starting point for the mathematical formulation is a variable transformation, which allows us to change a free boundary into a fixed boundary one. It is then possible to obtain the free-vibration analytical solution, as far as possible, and then use numerical integration schemes to obtain the forced vibration time responses. As motivation, we can firstly mention the unquestionable role of the oil and gas industry for the world economy, besides its increasing market share within the national economy. The discovery of the Tupi Field, in the Santos Basin, which represents the biggest oil and gas reserve of the Country, gave impulse to investments and research in all fields associated to the oil and gas area, in ultra deep water (depth around 2.500m), besides the well known need of research in deep water (depth around 2.000m). In spite of the growing research on alternative sources of energy, the world still demands not only oil and gas, but also polymers and plastic components, and this will still be the scenario for the next decades. Besides that, the increasing of knowledge in carbon sequestration may keep up the use of oil and gas for some more decades, hopefully with less environment impact.

Submitted by Aline Batista (alinehb.ufpel@gmail.com) on 2018-06-21T22:25:06Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_Maria_da_Graca_Pereira_Pimentel.pdf: 1105022 bytes, checksum: a8ce676040253811180c0351efada9a1 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2018-06-21T22:44:49Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_Maria_da_Graca_Pereira_Pimentel.pdf: 1105022 bytes, checksum: a8ce676040253811180c0351efada9a1 (MD5) / Made available in DSpace on 2018-06-21T22:44:49Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_Maria_da_Graca_Pereira_Pimentel.pdf: 1105022 bytes, checksum: a8ce676040253811180c0351efada9a1 (MD5) Previous issue date: 2007-02-18 / Sem bolsa / Um modelo de equações de regressão linear múltiplas, foi utilizado para realização de estimativas das temperaturas mínimas (Tmin) e máximas (Tmax) médias mensais do ar. As variáveis independentes adotadas como preditores, foram latitude, longitude e altitude e valores de temperaturas mínimas e máximas médias mensais da ar de noventa anos de dados (1913-1992) de quarenta estações meteorológicas de Estado do Rio Grande do Sul, como variáveis dependentes ou preditantes. A altitude influi significativamente na determinação das temperaturas mínimas e máximas. A latitude contribui em ambas de forma significativa mas atua mais intensamente sobre as temperaturas máximas. A longitude, é um fator pouco relevante e praticamente negligenciável sobre as temperaturas mínimas mas sobre as temperaturas máximas é mais intenso. O modelo faz boas estimativas das temperaturas mínimas e máximas, com exceção de alguns meses, e para algumas estações, nas quais o efeito da oceanidade/continentalidade se manifesta. Os baixos dos coeficientes de correlação para as temperaturas máximas nas sub-séries 30 A, 30 B e 30 C indicam que as estimativas mais eficientes devem considerar séries longas de dados. O modelo realizou boas estimativas das temperaturas mínimas e máximas médias mensais apresentando pequenos erros absolutos. / Multiple linear regression model equations, to estimate the average monthly minimum (Tmin) and maximum air temperature (Tmax), were established using latitude, longitude and altitude as independent variables and 90 years (1913-2002) of minimum and maximun average monthly air temperature data from forty meteorological stations, situated in the State of Rio Grande do Sul (Brazil) as dependent variables. The altitude shows a great influence in minimum and maximum air temperature. The latitude makes contribution in both, but more strongly over maximum temperatures. The longitude, is a low relevant factor and practically negligenceable about the minimum temperatures but in the maximum temperarures is more relevant. The model make very good estimations of minimum and maximum temperatures, except for some months, and to some meteorological stations in which the continental-oceanic effect are present. The smaller values of correlations coefficients of the maximum temperatures in years interval 30 A, 30 B and 30 C subseries denote that the more efficient estimations have to include long series of data.

Une étude en deux parties a été effectuée sur la préparation et la caractérisation de céramiques de ZnSe et de verres de phosphate à des fins optiques. Pour préparer des poudres de ZnSe, deux voies de synthèse ont été utilisées: i) hydrothermales; ii) le broyage à billes. La taille des particules ainsi que leur morphologie a été analysée par différentes techniques (DRX, MEB…). Ensuite, deux technologies de frittage, pressage à chaud (HP) et frittage flash (SPS), ont été mises en œuvre pour obtenir des échantillons massifs de ZnSe optiquement transparents. La meilleure transmission obtenue dans le domaine du moyen infrarouge, pour les échantillons HP et SPS, est supérieure à 50% et 40% respectivement. Pour obtenir des verres de phosphate avec une grande durabilité chimique, des cations avec une intensité de champ élevée tels que Nb5+ et Ti4+ ont été incorporés dans un verre de phosphate. La transparence dans le domaine du visible a été obtenue en utilisant de petites quantités d'agents d'oxydation tels que les sulfates ou les nitrates. L’utilisation de la spectroscopie par réflectance diffuse a permis de déterminer les coordonnées chromatiques afin d’évaluer le bénéfice de ces ajouts. / A two-part study was conducted on the preparation and characterization of ZnSe ceramic and phosphate glasses for optical applications in the visible and infrared range. To prepare ZnSe powders, two synthetic routes were used: i) hydrothermal; ii) ball milling. The size and morphology of synthesized powders were analyzed using different techniques (XRD, SEM…). Then two sintering technologies, hot pressing (HP) sintering and spark plasma sintering (SPS) sintering have been implemented to obtain optically transparent ZnSe bulk samples. The best transmission obtained in the mid-infrared range, using HP and SPS, is greater than 50% and 40% respectively. To synthesize phosphate glasses with a high chemical durability, cations with high field strength such as Nb5+ and Ti4+ were incorporated into a phosphate matrix. The transparency in the visible range was obtained using small amounts of oxidation agents such as sulfates or nitrates. The use of diffuse reflectance spectroscopy led to determination of the chromaticity coordinates to evaluate the benefit of these additions.

A time-domain backprojection processor for airborne synthetic aperture radar (SAR) has been developed at the University of Massachusetts’ Microwave Remote Sensing Lab (MIRSL). The aim of this work is to produce a SAR processor capable of addressing the motion compensation issues faced by frequency-domain processing algorithms, in order to create well focused SAR imagery suitable for interferometry. The time-domain backprojection algorithm inherently compensates for non-linear platform motion, dependent on the availability of accurate measurements of the motion. The implementation must manage the relatively high computational burden of the backprojection algorithm, which is done using modern graphics processing units (GPUs), programmed with NVIDIA’s CUDA language. An implementation of the Non-Equispaced Fast Fourier Transform (NERFFT) is used to enable efficient and accurate range interpolation as a critical step of the processing. The phase of time- domain processed imagery is dif erent than that of frequency-domain imagery, leading to a potentially different approach to interferometry. This general purpose SAR processor is designed to work with a novel, dual-frequency S- and Ka-band radar system developed at MIRSL as well as the UAVSAR instrument developed by NASA’s Jet Propulsion Laboratory. These instruments represent a wide range of SAR system parameters, ensuring the ability of the processor to work with most any airborne SAR. Results are presented from these two systems, showing good performance of the processor itself.

Rychlý vývoj v oblasti mobilní informatiky vyústil v nový, alternativní způsob mobilní komunikace, v němž mobilní uzly tvoří samoorganizující se bezdrátovou síť, jíž se říká mobilní síť ad hoc (Mobile Ad hoc Network, MANET). Specifické vlastnosti sítí MANET stavějí návrh síťového protokolu před řadu problémů na všech vrstvách protokolové sady . Příčinou jsou nepředvídatelné změny topologie a mobilní povaha těchto sítí. Nástrojem, který řeší problémy plynoucí z mobility uzlů, je predikce budoucích změn v topologii sítě. To má zásadní význam pro různé úlohy jako přesměrování. Tato disertační práce se zabývá dvěma metodami predikce mobility pro sítě MANET. První metoda se nazývá „predikce mobility s využitím virtuální mapy“ (mobility prediction using virtual map) a předpokládá, že každý uzel si dokáže vybudovat svou virtuální mapu v závislosti na svém umístění v průběhu času. Vyvinutý predikční algoritmus byl implementován do síťového simulátoru NS-2, aby jej bylo možné vyhodnotit. V této práci zkoumám stávající modely mobility a způsob, jakým v nich lze aplikovat tuto metodu predikce. Simulace sledují zlepšení výkonnosti, co se týče průměrného zpoždění na bázi end-to-end, poměru doručených paketů a propustnosti sítě. Navržený koncept predikce byl implementován pomocí směrovacího protokolu AODV(Ad Hoc On-Demand Distance Vector). Pro druhou metodu jsem vyvinula umělou neuronovou síť pro predikci pohybů v sítích MANET. Model pro predikci mobility vznikl na základě dat shromážděných ze vzorců umístění. K učení či trénování ANN byl využit bayesovský přístup. Ten byl implementován v softwaru pro trénování bayesovských neuronových sítí s názvem Model Manager. Nejlepším způsobem hodnocení závěrečného modelu je provedení predikcí a jejich srovnání s cílovými daty. Predikce vznikají na základě 50 vzorců jako vstupních proměnných. Dosažené výsledky prezentované s diskutované v práci se vyznačují zlepšením zásadních parametrů komunikační sítě, jako jsou propustnost, zpoždění, Poměr doručených paketů, až o 30% v porovnání s klasickým směrovacím protokolem AODV, kde není implementován predikční model.

My thesis deals with the construction of on-board computers for a motorcycle. The scheme is based on the parameters of onboard computers appearing on the market. In comparison with the models, which are offered commercially it also allows measurement of the motorcycle’s fuel consumption and location by using GPS. On-board computer measures speed, traveled distance, motor speed and engine temperature. It is controlled by a pair of eight-bit AVR microcontrollers. The measured data are showed by a graphical LCD display with touch screen.

This thesis deals with functional magnetic resonance imaging (fMRI), in particular with dynamic causal modelling (DCM) as one of the methods for effective brain connectivity analysis. It has been studied the effect of signal coordinates selection, which was used as an input of DCM analysis, on its results based on simulated data testing. For this purpose, a data simulator has been created and described in this thesis. Furthermore, the methodology of testing the influence of the coordinates selection on DCM results has been reported. The coordinates shift rate has been simulated by adding appropriate levels of various types of noise signals to the BOLD signal. Consequently, the data has been analyzed by DCM. The program has been supplemented by a graphical user interface. To determine behaviour of the model, Monte Carlo simulations have been applied. Results in the form of dependence of incorrectly estimated connections between brain areas on the level of the noise signals have been processed and discussed.

The main fokus of this D thesis consists in the creating of horizontal points in Lešná village that is closed to Valašské Meziříčí, part Vysoká. Sixty five points of horizontal control (PPBP) were located and set in Vysoká. The network adjustment was done with the help of the method of lest squares and coordinates were counted with the G-NET/Mini programme.

Subject of this master´s thesis is a station testing of Mobile automated astronomical system No. 1 (MAAS – 1). This system is used for measurement of astronomical coordinates by measurments of the stars. This thesis is focused on impact of some systematic effects, especially effects of inaccurate input geographic coordinates to resulting coordinates.

Táto práca popisuje niekoľko vybraných algoritmov, ktoré boli primárne vyvinuté pre CPU procesory, avšak vzhľadom k vysokému dopytu po ich vylepšeniach sme sa rozhodli ich využiť v prospech GPGPU (procesorov grafického adaptéra). Modifikácia týchto algoritmov bola zároveň cieľom nášho výskumu, ktorý  bol prevedený pomocou CUDA rozhrania. Práca je členená podľa troch skupín algoritmov, ktorým sme sa venovali: detekcia objektov v reálnom čase, spektrálna analýza obrazu a detekcia čiar v reálnom čase. Pre výskum detekcie objektov v reálnom čase sme zvolili použitie LRD a LRP funkcií.  Výskum spektrálnej analýzy obrazu bol prevedný pomocou PCA a NTF algoritmov. Pre potreby skúmania detekcie čiar v reálnom čase sme používali dva rôzne spôsoby modifikovanej akumulačnej schémy Houghovej transformácie. Pred samotnou časťou práce venujúcej sa konkrétnym algoritmom a predmetu skúmania, je v úvodných kapitolách, hneď po kapitole ozrejmujúcej dôvody skúmania vybranej problematiky, stručný prehľad architektúry GPU a GPGPU. Záverečné kapitoly sú zamerané na konkretizovanie vlastného prínosu autora, jeho zameranie, dosiahnuté výsledky a zvolený prístup k ich dosiahnutiu. Súčasťou výsledkov je niekoľko vyvinutých produktov.