O etanol, produto proveniente da indústria sucroalcooleira, um dos setores mais importantes da economia brasileira, atrai a atenção dos países desenvolvidos. O aumento de sua demanda em todo o mundo, motivado por razões econômicas e ambientais, impulsiona sua exportação. O volume exportado passou de 750 milhões de litros em 2003 para 3,5 bilhões de litros em 2006 e os produtores estimam que em cinco anos este volume alcance 6,5 bilhões de litros. Diante da perspectiva de acréscimo nas exportações, e do fato de quase 90% da produção brasileira concentra-se no Centro-Sul, esta dissertação tem por objetivo analisar as alternativas de transporte de etanol para exportação no médio prazo, baseado no plano de investimentos proposto pelo projeto do corredor de exportação de etanol da Transpetro, um dos investimentos propostos para melhorar a eficiência logística do transporte de etanol. Tais investimentos pretendem atender a demanda instalada pelo mercado internacional de forma satisfatória, garantindo o suprimento do combustível e prevenindo o surgimento de gargalos logísticos motivados por falta de infra-estrutura suficiente para o escoamento da produção. Foram avaliadas três alternativas de transporte que representam a movimentação de etanol das unidades produtoras aos portos: alternativa rodoviária, alternativa rodo-dutoviária, e alternativa rodo-hidro-dutoviária. Definidas as alternativas, foram identificadas as trinta principais zonas produtoras de etanol e analisadas as alternativas específicas para cada uma. Assim, foi possível identificar as principais vantagens competitivas das alternativas de transporte por região produtora e verificar os ganhos derivados do transporte por dutos e pela hidrovia no escoamento da produção de etanol até os principais portos. / Ethanol, a product originated from the sugarcane and ethanol industry, one of the most important sectors in the brazilian economy is attracting the interest of the developed countries. The exportation of ethanol is stimulated by the increasing worldwide demand driven by economic and environmental reasons. The exported volume increased from more than 750 million liters in 2003 to 3.5 billion liters in 2006 and, in the next five years, the brazilian producers expect that this volume will reach 6.5 billion liters. Because of this expectation in increasing exportations of ethanol, and being aware that the center-south region of Brazil produces almost 90% of the brazilian ethanol, the objective of this dissertation is to analyze the alternatives of transportation of ethanol for exportation in the medium term. This study is based in the Transpetro´s corridor of ethanol exportation investment plan, which is one of the proposed investments to increase the logistic efficiency of the transportation of ethanol. These investments intend to satisfactorily fulfill the demand of the international market, guaranteeing the supply of ethanol and preventing the appearance of logistic gaps due to lacks of infra-structure for transporting the product. Three alternatives of transportation were evaluated, representing the transportation of ethanol from the manufacturing units to the ports: roadway alternative, road-pipeline alternative and road-waterway-pipeline alternative. After the definition of these alternatives, the thirty major manufacturing zones of ethanol were defined and each zone had these alternatives analyzed. As a result, the major competitive advantages of the transportation alternatives by zone were identified. Also, the potential gains of transporting ethanol to the major seaports by pipelines and waterways were evaluated.

Apresenta-se um modelo matemático que avalia numericamente a estabilidade do estado estacionário para escoamentos água-ar em sistemas pipeline-riser de geometria variável. Uma análise a partir da teoria de estabilidade linear é aplicada a um modelo matemático adequado ao escoamento água-ar no sistema pipeline-riser. O modelo considera equações de continuidade para a fase líquida e para a fase gasosa, admite-se escoamento unidimensional e em condição isotérmica. O líquido é considerado incompressível enquanto que a fase gasosa é considerada um gás ideal. Admite-se uma equação de momento simplificada para mistura onde despreza-se a inércia (NPW - Modelo No Pressure Wave) e o padrão de escoamento local é definido com base nas condições do escoamento e na inclinação local. Assim, a intermitência severa é controlada principalmente pela gravidade no riser e pela compressibilidade do gás no pipeline. Tanto a correlação de fluxo de deriva quanto o cálculo da queda de pressão por atrito, adotados como lei de fechamento do modelo, são determinados em função do padrão de escoamento. Injeção de gás e válvula de choke são consideradas, respectivamente, na base e no topo do riser. O modelo é aplicado à sistemas pipeline-riser com escoamento água-ar citados na literatura. Os resultados da análise de estabilidade linear numérica são comparados aos resultados experimentais e numéricos apresentando uma excelente concordância. / A mathematical model that numerically evaluates the stability of the stationary state for hilly terrain air-water flows systems is presented. Numerical linear stability analysis is performed to a suitable mathematical model for the two-phase flows in a pipeline-riser system. The mathematical model considers the continuity equations for the liquid and gas phases, one-dimensional flow and isothermal conditions. The liquid is assumed incompressible while the gas phase is considered as an ideal gas. A simplified momentum equation for the mixture, neglecting inertia (NPW - No pressure wave model) is considered and the local flow pattern is defined based on the flow conditions and the local inclination. In this way, severe slugging is controlled mainly by gravity in the riser and compressibility in the pipeline. The void fraction and friction pressure drop, utilized as closure laws, are determined based on the local flow pattern. Gas injection at the bottom of the riser and a choke valve at the top are considered. The model is applied to air-water pipeline-riser systems reported in the literature. Numerical linear stability analysis results are compared with experimental and numerical results reported in the literature with excellent agreement.

Uma grande variedade de modelos é utilizada para estimar a pressão de ruptura de dutos contendo defeitos de corrosão. O presente trabalho tem como objetivo estudar a precisão dos modelos mais comuns e avaliar a pressão de ruptura de dutos submetidos à corrosão. Os modelos avaliados são: ASME B31G, ASME B31G modificado, DNV RP F101 e PCORRC. O estudo é baseado em mais de 400 resultados de ensaios de ruptura em dutos corroídos, todos coletados da literatura. A base de dados contem defeitos de corrosão reais e artificiais. Uma análise estatística foi realizada para a variável erro de modelo. Uma análise de regressão não-linear foi realizada para investigar os efeitos da variável erro de modelo, das variáveis mais relevantes, como profundidade e comprimento do defeito, e tensão de ruptura do aço. Uma análise de confiabilidade foi realizada a partir das estatísticas obtidas da variável erro de modelo, sendo estimado o índice de confiabilidade e a probabilidade de falha do duto com defeitos de corrosão, através do método iterativo de primeira ordem, denominado FORM (First Order Reliability Method). Nesta análise avaliou-se a evolução da probabilidade de falha com o aumento da profundidade do defeito, bem como foram identificadas as variáveis aleatórias mais importantes na falha do duto. O estudo pode ajudar aos operadores a eleger qual modelo utilizar em análises de risco, proporcionando mais segurança às operações dutoviárias. / A variety of models exist to estimate burst pressures of pipelines containing corrosion defects. The objective of this work is to study the accuracy of some of the most popular empirical burst pressure models. The study addresses the models: ASME B31G, ASME B31G Modified, DNV RP-F101 and PCORRC. The investigation is based on over 400 burst test results, all collected from the literature, containing both real and artificial corrosion defects. A statistical analysis is performed for assessing the accuracy of semi-empirical models by using a model error variable. A non-linear regression analysis is performed to identify the influence, on model errors, of the most relevant variables, such as defect depth and length and steels rupture tension. A reliability analysis was carried out, using model error statistics developed herein, in order to evaluate reliability index and probability of failure of pipelines containing corrosion defects, through the iterative first order reliability method, or FORM - First Order Reliability Method. The evolution of failure probabilities, with increasing defect depth, was investigated. The most relevant random variables were identified. The study can help operators choose a proper empirical model to use in their risk analysis, leading to greater safety in pipeline operations.

O presente trabalho tem como objetivo avaliar a influência do efeito da corrosão no comportamento geotécnico de condutos enterrados através da utilização de ensaios em modelos reduzidos. Foram empregados diferentes padrões de corrosão, em que se variou o grau e a localização da corrosão. Os resultados do trabalho mostram as localizações mais danosas à estrutura, correlacionando resultados dos tubos corroídos com os de tubos intactos. O duto danificado desencadeou um carregamento assimétrico que deve ser considerado para a prevenção de possíveis deslocamentos. Finalmente, o trabalho avalia a influência conjunta da corrosão e da flexibilidade do conduto no comportamento mecânico das tubulações enterradas. De modo a permitir comparações para averiguar a validade do modelo laboratorial adotado, utilizaram-se simulações numéricas, que possibilitam o estudo do problema de forma mais abrangente. / This work evaluates the influence of corrosion effect on the geotechnical behavior of underground conduits. Small-scale tests were carried out on two different types of pipes, in which the degree and location of the corrosion were changed. The results show the most harmful corrosion locations relative to the intact conduits. The damaged conduits built in and located under asymmetric condition behave as if they were subjected to an asymmetric loading condition and this must be considered to the prevention of possible displacements. Finally, the work evaluates the joined influence of the corrosion and conduit\'s flexibility on the mechanical behavior of underground pipelines. To allow comparisons to inquire the validation of the adopted laboratorial model, numeric simulations were used, which enable the study of the problem considering other corrosion layouts.

Vazamentos decorrentes de acidentes envolvendo dutos constituem uma fonte potencial de contaminação das águas subsuperficiais, superficiais e dos componentes dos meios físico e biológico, em geral. Neste trabalho são analisados os problemas ambientais decorrentes de possíveis vazamentos dos produtos transportados no poliduto OSBRA, no trecho situado entre Porto Ferreira e Ribeirão Preto (SP). Este trecho está localizado em uma área de intensa ocupação agrícola, atravessando extensa área de recarga da Formação Botucatu e de basaltos fraturados pertencentes à Formação Serra Geral, além de vários canais de drenagem. Todas estas áreas estão, portanto, sujeitas à contaminação em caso de acidentes envolvendo o duto. Neste trabalho são apontados os principais agentes deflagadores de possíveis acidentes no trecho e analisados os diferentes contextos de contaminação de acordo com as características do meio físico e do produto liberado. / Leakage from pipeline constitute a potential source of groundwater and surface water contamination as well as to geological and biological environment components. In this research the environmental problems due to leaking of petroleum products transported by OSBRA pipeline, which runs between Porto Ferreira and Ribeirão Preto (SP), are analyzed. It is located in an area of intense agricultural management, crossing large and recharge area of Botucatu Formation and fractured basaltic rocks from Serra Geral Formation. All these areas are, therefore, subject to the contamination in case of accidents involving the pipeline. The aim of this research is to analyze the agents responsible by the accidents and to determine the different types of contamination according to the main characteristic of the environment and spill material.

This thesis presents the ADT transverse instability detection system, the next generation of instability detection in the LHC at CERN, Geneva. The system is presented after a thorough study of underlying causes for instabilities in high energy particle accelerators, current parallel programming paradigms, the available hardware and software at CERN and possible instability detection techniques. The requirements for the system involve handling vast amounts of data which need to be analyzed in real-time and in this data detect rapid amplitude growth while limiting the computational resources required to a minimum. The result of this thesis was a system that could generate a trigger when an instability was detected, which was used to save data from observation instruments around the LHC. A fixed display in the CERN control centre was also created which allows scientists and operators at CERN to monitor the oscillation amplitude of all particle bunches. The conclusion is that the complete system will be a valuable asset at CERN to help further develop the LHC.

This study is an industrial project commissioned by British Gas plc. (UK) to investigate the state of in-service naturally aged polyethylene (PE) buried pipes and to define procedures or techniques available to facilitate the condition assessment programme of PE pipelines systems. The primary goal of this study was to establish a better understanding of the ageing process in commercial piping materials and to understand its effect on long term integrity of PE pipeline systems. Eltex, Rigidex and Aldyl A are trade names of the PE gas grade resins used in this study and they represent the range of pipe materials used in the transport of potable water and gas in the UK. Sections of pipes used in this project were supplied by British Gas plc. in the form of unaged pipes and pipes which were aged in-service. Laboratory based accelerated ageing of the pipe resin samples was also carried out. The ageing regimes considered were water ageing at 23°C, air-oven ageing at 80°C, water ageing at 80 C, vacuum ageing at 80°C and in-service aged samples. Compression moulded plaques were produced as reference material. By utilising specific instrumentation and designs, several reliable procedures were developed to produce specimens directly from pipes. The feasibility of using micro-samples instead of large samples was demonstrated. A methodology was developed to retrieve disk samples using electrofusion "tapping-tee" saddles. Appropriate test specimens were designed for chemical and physical evaluations. This sampling method negates the need for excavating large sections of pipe material for the purpose of condition assessment. Reliable micro and macro-sampling test methods were developed and established as techniques for the condition assessment programme. Characterisation techniques included: (i) differential scanning calorimetry (DSC) to measure (from the same specimen) both the degree of crystallinity and the oxidation induction time (OIT), (ii) HPLC analysis was used to quantify additives concentrations, (iii) Fourier transform infrared spectroscopy was used to monitor the carbonyl index and to identify a pipe resin type from site, (iv) micro- and macro-tensile and fatigue tests to assess the changes in the mechanical properties as function of ageing. The fatigue test procedure was developed to produce brittle fracture at laboratory scale within a shorter period of time as compared to existing procedures such as the hydrostatic test. A reference data-base was created using the above identified tools and the criteria and methodology for carrying out site condition assessment inspection was compiled. The fundamental mechanisms of chemical and physical ageing were studied along with the possibility of their effect on the mechanical properties of PE pipes.

The workflow of different game modelling artists is explored, with the goal of creating a melee weapon designed for games. A low polygon weapon was created using the research into the most common components from professional workflows of creating game models. One of the goals for the paper was to obtain a greater understanding of professional workflows when creating models for games. Other goals were to utilize the research and design a finished game model from concept to end product.

When developing applications in Direct3D today, developers can choose between using the fixed function pipeline and the programmable pipeline. The programmable pipeline is more flexible than the fixed function pipeline, but what is the price for high flexibility? Is high flexibility desired at any cost? How is the choice of pipeline affecting performance? The purpose of this master thesis is to evaluate the performance of the two pipelines. This will be achieved by developing a benchmark program, which measures performance when various graphical effects are tested. The results of the evaluation will hopefully help developers to decide which pipeline to use, in terms of performance. In the end we will see that the fixed function pipeline is faster than the programmable pipeline in all our tests.

This report documents implementation details, results, benchmarks and technical discussions for the work carried out within a master’s thesis at Linköping University. Within the master’s thesis, the field of software rendering is explored in the age of parallel computing. Using the Open Computing Language, a complete graphics pipeline was implemented for use on general processing units from different vendors. The pipeline is tile-based, fully-configurable and provides means of rendering visually compelling images in real-time. Yet, further optimizations for parallel architectures are needed as uneven work loads drastically decrease the overall performance of the pipeline.