This study was based on the uncertainty and sensitivity analysis of a generic 10 MW Materials Test Reactor (MTR). In this study an uncertainty and sensitivity analysis methodology called code scaling applicability and uncertainty (CSAU) was implemented. Although this methodology follows 14 steps, only the following were carried out: scenario specification, nuclear power plant (NPP) selection, phenomena identification and ranking table (PIRT), selection of frozen code, provision of code documentation, determination of code applicability, determination of code and experiment accuracy, NPP sensitivity analysis calculations, combination of biases and uncertainties, and total uncertainty to calculate specific scenario in a specific NPP. The thermal hydraulic code Flownex®1 was used to model only the reactor core to investigate the effects of the input parameters on the selected output parameters of the hot channel in the core. These output parameters were mass flow rate, temperature of the coolant, outlet pressure, centreline temperature of the fuel and surface temperature of the cladding. The PIRT process was used in conjunction with the sensitivity analysis results in order to select the relevant input parameters that significantly influenced the selected output parameters. The input parameters that have the largest effect on the selected output parameters were found to be the coolant flow channel width between the plates in the hot channel, the width of the fuel plates itself in the hot channel, the heat generation in the fuel plate of the hot channel, the global mass flow rate, the global coolant inlet temperature, the coolant flow channel width between the plates in the cold channel, and the width of the fuel plates in the cold channel. The uncertainty of input parameters was then propagated in Flownex using the Monte Carlo based uncertainty analysis function. From these results, the corresponding probability density function (PDF) of each selected output parameter was constructed. These functions were found to follow a normal distribution. / MIng (Nuclear Engineering), North-West University, Potchefstroom Campus, 2014

ABSTRACT UNCERTAINTY ASSESSMENT IN RESERVE ESTIMATION OF A NATURALLY FRACTURED RESERVOIR ERI&Ccedil / OK, &Ouml / zlen M.S., Department of Petroleum and Natural Gas Engineering Supervisor : Prof. Dr. Fevzi G&Uuml / MRAH December 2004, 169 pages Reservoir performance prediction and reserve estimation depend on various petrophysical parameters which have uncertainties due to available technology. For a proper and economical field development, these parameters must be determined by taking into consideration their uncertainty level and probable data ranges. For implementing uncertainty assessment on estimation of original oil in place (OOIP) of a field, a naturally fractured carbonate field, Field-A, is chosen to work with. Since field information is obtained by drilling and testing wells throughout the field, uncertainty in true ranges of reservoir parameters evolve due to impossibility of drilling every location on an area. This study is based on defining the probability distribution of uncertain variables in reserve estimation and evaluating probable reserve amount by using Monte Carlo simulation method. Probabilistic reserve estimation gives the whole range of probable v original oil in place amount of a field. The results are given by their likelyhood of occurance as P10, P50 and P90 reserves in summary. In the study, Field-A reserves at Southeast of Turkey are estimated by probabilistic methods for three producing zones / Karabogaz Formation, Kbb-C Member of Karababa formation and Derdere Formation. Probability density function of petrophysical parameters are evaluated as inputs in volumetric reserve estimation method and probable reserves are calculated by @Risk software program that is used for implementing Monte Carlo method. Outcomes of the simulation showed that Field-A has P50 reserves as 11.2 MMstb in matrix and 2.0 MMstb in fracture of Karabogaz Formation, 15.7 MMstb in matrix and 3.7 MMstb in fracture of Kbb-C Member and 10.6 MMstb in matrix and 1.6 MMstb in fracture of Derdere Formation. Sensitivity analysis of the inputs showed that matrix porosity, net thickness and fracture porosity are significant in Karabogaz Formation and Kbb-C Member reserve estimation while water saturation and fracture porosity are most significant in estimation of Derdere Formation reserves.

Orientador: Aparecido Carlos Gonçalves / Resumo: A falha catastrófica de caixas de engrenagens acarreta em perdas de produção e custos de manutenção. O elemento mecânico que mais falha em uma caixa de engrenagens é o próprio par engrenado. Estas falhas geralmente ocorrem devido a defeitos pontuais nos dentes como desgaste severo e presença de trincas, contrariando os fatores de segurança previamente definidos por normas referentes aos critérios de falhas em engrenagens. O monitoramento da condição do par engrenado busca avaliar parâmetros representativos dos mecanismos de falha do par engrenado. As técnicas de monitoramento da condição mais utilizadas são a análise de vibrações e análise de lubrificantes. Este trabalho realiza uma revisão bibliográfica de técnicas de monitoramento da condição. A parte experimental consiste na avaliação de uma bancada sob três condições: desgaste severo ao longo da vida útil da engrenagem; engrenagem entalhada para simulação de trinca; engrenagem com variação do entalhe para simulação de uma propagação de trinca. A condição da bancada foi avaliada utilizando técnicas de tratamento de sinais de vibração como TSA, sinal residual, demodulação temporal e análise estatística via PDF beta e; técnicas de análise de lubrificantes como contagem de partículas e espectrometrias de raios-x e infravermelho. Todas as técnicas se mostraram adequadas na avaliação da evolução do desgaste excetuando a espectrometria de infravermelho. Apenas as técnicas de vibração se mostraram adequadas para identificar a pre... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The catastrophic failure of gearboxes results in production losses and maintenance costs. The mechanical component that most fails in gearboxes are the gears. These failures usually occur before the end of useful life projected by criteria of failure standards due teeth defects as severe wear and cracking. The condition monitoring of gearboxes evaluates parameters which can indicate the mechanism of failure in process in the gear. The most commonly used monitoring techniques of gearboxes are vibration analysis and lubricant analysis. Firstly, this work performs a bibliographic review of condition monitoring techniques. The experimental analysis consists of the evaluation of an experimental workbench under three conditions: severe wear throughout the life of the gear; notched gear for crack simulation and; gear with variation of notch for simulation of a crack propagation. The workbench condition was evaluated using vibration signal treatment techniques such as TSA, Residual Signal, Demodulation, Statistical Moments, Crest Factor and Statistical Analysis using PDF beta and; techniques for analyzing lubricants such as particle counting and x-ray and infrared spectrometry. All the techniques were adequate to evaluate the evolution of wear except infrared spectrometry. Only the vibration techniques were adequate to identify the presence an evolution of the notch. Statistical analysis using PDF beta was useful to identify the degradation of a tooth as the notch size evolved. / Mestre

L’Analyse Linéaire de Stabilité a été largement utilisée afin de décrire l’évolution du mode dominant des instabilités pour différentes configurations. Toutefois, plusieurs observations expérimentales et numériques ont démontré l’existence de distributions de longueurs inter-strictions, prémices aux distributions de tailles de fragments. Une extension de cette utilisation classique de l’Analyse Linéaire de Stabilité dédiée à l’extension d’un barreau en traction a été proposée afin de rendre compte de la contribution de l’ensemble des modes de perturbation sur le profil final des strictions. Cette approche, correspondant physiquement au cas des anneaux fins en expansion, est à même de déterminer une distribution de longueurs inter-strictions. En se basant sur les mêmes outils mathématiques que ceux ayant permis d’étendre l’analyse linéaire de stabilité, une nouvelle approche numérique a été suivie afin de déterminer le temps d’apparition et le nombre de strictions en fonction de la vitesse de chargement, de l’amplitude et de la taille de cellules de perturbations. Une comparaison, en termes de distribution de longueurs inter-strictions, a été par la suite obtenue entre résultats analytiques et numériques. De bonnes corrélations ont été observées. Le développement d’un montage expérimental d’expansion d’anneaux par forces électromagnétiques a été entamé au cours de ce travail de thèse. Lors de sa finalisation, il devrait permettre une validation expérimentale des approches développées dans les domaines numériques et analytiques / Linear Stability Analysis has been widely used in order to describe the evolution of the dominant necking pattern in different configurations. However, experimental and numerical observations have demonstrated that a distribution of internecking lengths is obtained instead of a unique dominant pattern. In this work, an extension of the classical Linear Stability Analysis applied to the dynamic extension of a round bar case has been developed to take into account the contribution of all perturbation modes on the final necking pattern. This approach, corresponding physically to the case of thin ring expansion, is able to determine a distribution on internecking distances. Based on the same mathematical tools that was developed for the extension of the linear stability analysis, a new numerical approach has been followed to determine the number and the onset time of necking with respect to loading velocity, amplitude and cell size of the perturbations. A comparison, in terms of distributions of inter-necking distance, has been carried out between analytical and numerical results. Good correlations have been observed. An electromagnetic ring expansion experimental device has been proposed during this work. Whith some additional development, it should enable to validate experimentally the working assumptions developed in the numerical and analytical studies

Submitted by Marcelo Braga Covo (mcovo@ibiunainvest.com.br) on 2015-03-17T16:48:46Z No. of bitstreams: 1 tesecovo.pdf: 385739 bytes, checksum: 253e4c0b5c2b22775f64b6e31b4c0cea (MD5) / Approved for entry into archive by GILSON ROCHA MIRANDA (gilson.miranda@fgv.br) on 2015-04-07T14:13:51Z (GMT) No. of bitstreams: 1 tesecovo.pdf: 385739 bytes, checksum: 253e4c0b5c2b22775f64b6e31b4c0cea (MD5) / Approved for entry into archive by Marcia Bacha (marcia.bacha@fgv.br) on 2015-04-08T17:19:58Z (GMT) No. of bitstreams: 1 tesecovo.pdf: 385739 bytes, checksum: 253e4c0b5c2b22775f64b6e31b4c0cea (MD5) / Made available in DSpace on 2015-04-08T17:20:13Z (GMT). No. of bitstreams: 1 tesecovo.pdf: 385739 bytes, checksum: 253e4c0b5c2b22775f64b6e31b4c0cea (MD5) Previous issue date: 2009-06-01 / Este trabalho demonstra como podemos usar opções sobre o Índice de Taxa Média de Depósitos Interfinanceiros de Um Dia (IDI) para extrair a função densidade de probabilidade (FDP) para os próximos passos do Comitê de Política Monetária (COPOM). Como a decisão do COPOM tem uma natureza discreta, podemos estimar a FDP usando Mínimo Quadrados Ordinários (MQO). Esta técnica permite incluir restrições sobre as probabilidades estimadas. As probabilidades calculadas usando opções sobre IDI são então comparadas com as probabilidades encontradas usando o Futuro de DI e as probabilidades calculadas através de pesquisas. / This paper demonstrates how options on the One-day Brazilian Interfinancial Deposits Index (IDI) can be used to recover the implied probability density function (PDF) for futures Monetary Policy Committee (COPOM) outcomes. The discrete nature of the choices made by the COPOM allows recovering the PDF using ordinary least squares (OLS) estimation. This method also allows the imposition of restrictions on the recovered probabilities. Recovered probabilities using options on IDI are then compared to the probabilities obtained using the futures on DI and the probabilities recovered by surveys.

Made available in DSpace on 2015-03-26T12:27:13Z (GMT). No. of bitstreams: 1 texto completo.pdf: 3360592 bytes, checksum: 7d67d4fcf4c95ec01e67b457ff878b1e (MD5) Previous issue date: 2012-08-01 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The objective of the present work to start several projects with the aim of generating free systems to assist forest managers, academics and extension in solving some problems in the forest sector. The projects are started the RPF (forest regulation system), OtimTotas (optimization of multiproduct of timber system), FitFD (system for fitting of probability density functions), and Select (system for selection of data for growth and yield modeling). The projects were developed using the Java programming language. As development environment we used the IDE (Integrated Development Environment) Netbeans 7.1 and JDK 7.3 (Java Development Kit) the four systems were implemented and are freely available on the site NeuroForest (http://neuroforest.ucoz.com/) and is presented for flexible and efficient resolution of problems to which they have. / Objetivou-se no presente trabalho iniciar diversos projetos com o intuito de gerar sistemas gratuitos, para auxiliar gestores florestais, acadêmicos e extensionistas, na resolução de alguns problemas do setor florestal. Os projetos iniciados são o RPF (sistema para regulação da produção florestal), OtimTotas (sistema para otimização de multiprodutos madeireiros), FitFD (sistema para ajuste de funções densidade de probabilidade), e o Select (sistema para seleção de dados para ajuste de modelos de crescimento e produção). Os projetos foram desenvolvidos utilizando a linguagem de programação Java. Como ambiente de desenvolvimento foi utilizado a IDE (Integrated Development Environment) Netbeans 7.1, e a JDK 7.3 (Java Development Kit). Os quatro sistemas foram implementados e estão disponibilizados gratuitamente no site NeuroForest (http://neuroforest.ucoz.com/) e se apresentaram flexíveis e eficientes para a resolução de problemas aos quais se dispõem.

Submitted by CARLOS EDUARDO SGOTTI (carlos.sgotti@hotmail.com) on 2018-04-27T18:42:48Z No. of bitstreams: 1 2018_Sgotti_Dissertação_Mestrado.pdf: 10994360 bytes, checksum: 90aa52990d9db0b33dd9950ddfb58289 (MD5) / Approved for entry into archive by Cristina Alexandra de Godoy null (cristina@adm.feis.unesp.br) on 2018-04-27T19:11:29Z (GMT) No. of bitstreams: 1 sgotti_ce_me_ilha.pdf: 10994360 bytes, checksum: 90aa52990d9db0b33dd9950ddfb58289 (MD5) / Made available in DSpace on 2018-04-27T19:11:29Z (GMT). No. of bitstreams: 1 sgotti_ce_me_ilha.pdf: 10994360 bytes, checksum: 90aa52990d9db0b33dd9950ddfb58289 (MD5) Previous issue date: 2018-02-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A falha catastrófica de caixas de engrenagens acarreta em perdas de produção e custos de manutenção. O elemento mecânico que mais falha em uma caixa de engrenagens é o próprio par engrenado. Estas falhas geralmente ocorrem devido a defeitos pontuais nos dentes como desgaste severo e presença de trincas, contrariando os fatores de segurança previamente definidos por normas referentes aos critérios de falhas em engrenagens. O monitoramento da condição do par engrenado busca avaliar parâmetros representativos dos mecanismos de falha do par engrenado. As técnicas de monitoramento da condição mais utilizadas são a análise de vibrações e análise de lubrificantes. Este trabalho realiza uma revisão bibliográfica de técnicas de monitoramento da condição. A parte experimental consiste na avaliação de uma bancada sob três condições: desgaste severo ao longo da vida útil da engrenagem; engrenagem entalhada para simulação de trinca; engrenagem com variação do entalhe para simulação de uma propagação de trinca. A condição da bancada foi avaliada utilizando técnicas de tratamento de sinais de vibração como TSA, sinal residual, demodulação temporal e análise estatística via PDF beta e; técnicas de análise de lubrificantes como contagem de partículas e espectrometrias de raios-x e infravermelho. Todas as técnicas se mostraram adequadas na avaliação da evolução do desgaste excetuando a espectrometria de infravermelho. Apenas as técnicas de vibração se mostraram adequadas para identificar a presença do entalhe. A análise estatística via PDF beta se mostrou útil para identificar a degradação de um dente conforme evolui o tamanho do entalhe. / The catastrophic failure of gearboxes results in production losses and maintenance costs. The mechanical component that most fails in gearboxes are the gears. These failures usually occur before the end of useful life projected by criteria of failure standards due teeth defects as severe wear and cracking. The condition monitoring of gearboxes evaluates parameters which can indicate the mechanism of failure in process in the gear. The most commonly used monitoring techniques of gearboxes are vibration analysis and lubricant analysis. Firstly, this work performs a bibliographic review of condition monitoring techniques. The experimental analysis consists of the evaluation of an experimental workbench under three conditions: severe wear throughout the life of the gear; notched gear for crack simulation and; gear with variation of notch for simulation of a crack propagation. The workbench condition was evaluated using vibration signal treatment techniques such as TSA, Residual Signal, Demodulation, Statistical Moments, Crest Factor and Statistical Analysis using PDF beta and; techniques for analyzing lubricants such as particle counting and x-ray and infrared spectrometry. All the techniques were adequate to evaluate the evolution of wear except infrared spectrometry. Only the vibration techniques were adequate to identify the presence an evolution of the notch. Statistical analysis using PDF beta was useful to identify the degradation of a tooth as the notch size evolved.

Orientador: Miched Daoud Yacoub / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-13T17:19:37Z (GMT). No. of bitstreams: 1 Souza_RausleyAdrianoAmaralde_D.pdf: 1070968 bytes, checksum: 289cdc544616610aa8ff990ce2ea0e82 (MD5) Previous issue date: 2009 / Resumo: Em comunicações móveis, o desvanecimento por múltiplos percursos é modelado por várias distribuições incluindo Hoyt, Rayleigh, Weibull, Nakagami-m e Rice. Nesta tese, são deduzidas expressões exatas para o modelo de duas variáveis Hoyt (Nakagami-q) com correlação arbitrária em um ambiente não estacionário. De forma específica, as seguintes estatísticas são encontradas: função densidade de probabilidade conjunta, função de distribuição cumulativa conjunta, coeficiente de correlação e algumas estatísticas relacionadas ao parâmetro SNR na saída do combinador de seleção, a saber, probabilidade de indisponibilidade e função densidade de probabilidade. As expressões fazem uso dos polinômios de Laguerre generalizados. Elas são matematicamente tratáveis e possuem flexibilidade suficiente para acomodar um grande número de cenários de correlação, úteis na análise de um ambiente com desvanecimento mais geral. Depois disto, aproveitando os resultados previamente deduzidos, expressões exatas relacionadas a processos Nakagami-m com duas variáveis com correlação arbitrária e parâmetros de desvanecimento igualmente arbitrários são encontradas. De forma mais específica, as seguintes estatísticas são obtidas neste trabalho: função geratriz de momentos, função densidade de probabilidade conjunta, função de distribuição cumulativa conjunta, coeficiente de correlação de potência, e várias estatísticas ligadas à relação sinal-ruído na saída do combinador de seleção, especialmente, probabilidade de indisponibilidade, função densidade de probabilidade e valor médio da relação sinal-ruído. Recentemente, o modelo de desvanecimento ®-µ foi proposto que leva em conta a não linearidade do meio de propagação assim como o fenômeno de cluster de múltiplos percursos das ondas de rádio. A distribuição ®-µ é geral, flexível e matematicamente tratável. Ela inclui importantes distribuições tais como Gamma (e suas versões discretas Erlang e Chi-Quadrada Central), Nakagami-m (e sua versão discreta Chi), Exponencial, Weibull, Gaussiana Unilateral e Rayleigh. Nesta tese, uma formulação através de série infinita para a função densidade de probabilidade multivariável ®-µ com matriz de correlação arbitrária e variáveis não identicamente distribuídas é encontrada. A expressão é exata e geral e inclui todos os resultados anteriormente publicados na literatura relacionados às distribuições compreendidas pela distribuição ®-µ. A expressão geral é então particularizada para uma solução aproximada simples na forma fechada. Adicionalmente, a função distribuição cumulativa conjunta multivariável é obtida, novamente, em uma forma fechada e simples. Os resultados exato e aproximado são muito próximos para valores pequenos e médio de correlação. Nós mantemos, entretanto, que uma relação entre os coeficientes de correlação das correspondentes componentes gaussianas deve ser mantida de forma a atender os critérios de convergência / Abstract: In wireless communications, the multipath fading is modeled by several distributions including Hoyt, Rayleigh, Weibull, Nakagami-m, and Rice. In this thesis, new, exact expressions for the bivariate Hoyt (Nakagami-q) processes with arbitrary correlation in a nonstationary environment are derived. More specifically, the following are obtained: joint probability density function, joint cumulative distribution function, power correlation coefficient, and some statistics related to the signal-tonoise ratio at the output of the selection combiner, namely, outage probability and probability density function. The expressions make use of the well known generalized Laguerre polynomials. They are mathematically tractable and flexible enough to accommodate a myriad of correlation scenarios, useful in the analysis of a more general fading environment. After this, capitalizing on result previously deduced, exact expressions concerning the bivariate Nakagami-mprocesses with arbitrary correlation and fading parameters are derived. More specifically, the following are obtained in the present work: joint moment generating function; joint probability density function; joint cumulative distribution function; power correlation coefficient; and several statistics related to the signal-to-noise ratio at the output of the selection combiner, namely, outage probability, probability density function, and mean SNR. More recently, the ®-µ fading model has been proposed that accounts for the non-linearity of the propagation medium as well as for the multipath clustering of the radio waves. The ®-µ distribution is general, flexible, and mathematically easily tractable. It includes important distributions such as Gamma (and its discrete versions Erlang and Central Chi-Squared), Nakagami-m (and its discrete version Chi), Exponential, Weibull, One-Side Gaussian, and Rayleigh. An infinite series formulation for the multivariate ®-µ joint probability density function with arbitrary correlation matrix and non-identically distributed variates is derived. The expression is exact and general and includes all of the results previously published in the literature concerning the distributions comprised by the ®-µ distribution. The general expression is then particularized to an indeed very simple, approximate closed-form solution. In addition, a multivariate joint cumulative distribution function is obtained, again in simple, closed-form manner. Approximate and exact results are very close to each other for small as well medium values of correlation. We maintain, however, that a relation among the correlation coefficients of the corresponding Gaussian components must be kept so that convergence is attained / Doutorado / Telecomunicações e Telemática / Doutor em Engenharia Elétrica

Multiphase flows are of great interest to a large variety of industries because flows of two or more immiscible liquids are encountered in a diverse range of processes and equipment. However, the advent of high viscosity oil requires more investigations to enhance good design of transportation system and forestall its inherent production difficulties. Experimental and numerical studies were conducted on water-sand, oil-water and oilwater- sand respectively in 1-in ID 5m long horizontal pipe. The densities of CYL680 and CYL1000 oils employed are 917 and 916.2kg/m3 while their viscosities are 1.830 and 3.149Pa.s @ 25oC respectively. The solid-phase concentration ranged from 2.15e-04 to 10%v/v with mean diameter of 150micron and material density of 2650kg/m3. Experimentally, the observed flow patterns are Water Assist Annular (WA-ANN), Dispersed Oil in Water (DOW/OF), Oil Plug in Water (OPW/OF) with oil film on the wall and Water Plug in Oil (WPO). These configurations were obtained through visualisation, trend and the probability density function (PDF) of pressure signals along with the statistical moments. Injection of water to assist high viscosity oil transport reduced the pressure gradient by an order of magnitude. No significant differences were found between the gradients of oil-water and oil-water-sand, however, increase in sand concentration led to increase in the pressure losses in oil-water-sand flow. Numerically, Water Assist Annular (WA-ANN), Dispersed Oil in Water (DOW/OF), Oil Plug in Water (OPW/OF) with oil film on the wall, and Water Plug in Oil (WPO) flow pattern were successfully obtained by imposing a concentric inlet condition at the inlet of the horizontal pipe coupled with a newly developed turbulent kinetic energy budget equation coded as user defined function which was hooked up to the turbulence models. These modifications aided satisfactory predictions.

The actual traffic flow theory assumes interactions only between neighbouring vehicles within the traffic. This assumption is reasonable, but it is based on the possibilities of science and technology available decades ago, which are currently overcome. Obviously, in general, there is an interaction between vehicles at greater distances (or between multiple vehicles), but at the time, no procedure has been put forward to quantify the distance of this interaction. This work introdukce a method, which use mathematical statistics and precise measurement of time distances of individual vehicles, which allows to determine these interacting distances (between several vehicles) and its validation for narrow densities of traffic flow. It has been revealed that at high traffic flow densities there is an interaction between at least three consecutive vehicles and four and five vehicles at lower densities. Results could be applied in the development of new traffic flow models and its verification.