Brayton cycles are open gas turbine cycles extensively used in aviation and industrial applications because of their advantageous volume and weight characteristics. With the bulk of waste exhaust heat and engine emissions associated, there is need to be mindful of environmentally-friendliness of these engine cycles, not compromising good technical performance, and economic viability. This research considers assessment of power plants in helicopters, and aeroderivative industrial gas turbines combined-heat-and-power (ADIGT-CHP) in the petrochemical industry. Thus, it consists of two parts: part A focuses on performance analysis of helicopter gas turbines, while part B entails technoeconomic and environmental risk assessment of ADIGT-CHP in the petrochemical industry. The investigation encompasses comparative assessment of simple cycle (SC) and advanced gas turbine cycle options including the component behaviours and the environmental and economic analysis of the systems. The advanced cycles considered include: recuperated (RC), intercooled (IC), intercooled-recuperated (ICR), and low pressure compressor zero-staged (LPC-ZS), cycles. The helicopter engines are analysed and subsequently converted to small-scale ADIGT engines. Also, modelling combined-heat-and-power (CHP) performances of small-scale (SS), and large-scale (LS) ADIGT engines is implemented. More importantly, a large part of the research is devoted to developing a techno-economic model for assessing, predicting, and comparing viability of simple and advanced cycle ADIGT-CHP in the petrochemical industry in terms of net present value (NPV), internal rate of return (IRR), and simple payback period (SPBP). The techno-economic performances of the ADIGT-CHP cycles are measured against the conventional case of grid power plus on-site boiler. Besides, risk and sensitivity of NPV with respect to uncertain changes in grid electricity cost, gas fuel cost, emission cost, and electricity export tariff, are investigated. Two case studies underlie the development of the techno-economic model. One case study demonstrates the application of the model for large-scale (LS) ADIGT-CHP, and the other for small-scale (SS) ADIGT-CHP, all in the petrochemical industry. By so doing, techno-economic and environmental risk analysis framework (a multi-disciplinary preliminary design assessment tool comprising performance, emissions, economic, and risk modules) is adapted to ADIGT-CHP in the petrochemical industry, which is the aim of this research. The investigation and results led to the conclusions that advanced cycle helicopter and ADIGT engines exhibit higher thermal efficiencies than simple cycle, and that savings exist in operational costs of ADIGT-CHP above the conventional case. Thus, for both SS ADIGT-CHP, and LS ADIGT-CHP cases, all ADIGT-CHP cycles are profitable than the conventional case. For LS ADIGT- CHP category, the IC ADIGT-CHP is the most profitable, whereas for SS ADIGT-CHP category, the RC ADIGT-CHP is the most profitable. The contribution to knowledge of this research is the development of a technoeconomic model for assessing, predicting, and comparing viability of simple and advanced cycle ADIGT-CHP in the petrochemical industry in terms of NPV, SPBP, and IRR over the conventional case of grid power plus on-site boiler. A second contribution is the derivation of simple and advanced cycle small-scale ADIGT and ADIGT-CHP from helicopter engines. Cont/D.

L’optimisation sans dérivées (OSD) a connu un regain d’intérêt ces dernières années, principalement motivée par le besoin croissant de résoudre les problèmes d’optimisation définis par des fonctions dont les valeurs sont calculées par simulation (par exemple, la conception technique, la restauration d’images médicales ou de nappes phréatiques).Ces dernières années, un certain nombre de méthodes d’optimisation sans dérivée ont été développées et en particulier des méthodes fondées sur un modèle de région de confiance se sont avérées obtenir de bons résultats.Dans cette thèse, nous présentons un nouvel algorithme de région de confiance, basé sur l’interpolation, qui se montre efficace et globalement convergent (en ce sens que sa convergence vers un point stationnaire est garantie depuis tout point de départ arbitraire). Le nouvel algorithme repose sur la technique d’auto-correction de la géométrie proposé par Scheinberg and Toint (2010). Dans leur théorie, ils ont fait avancer la compréhension du rôle de la géométrie dans les méthodes d’OSD à base de modèles. Dans notre travail, nous avons pu améliorer considérablement l’efficacité de leur méthode, tout en maintenant ses bonnes propriétés de convergence. De plus, nous examinons l’influence de différents types de modèles d’interpolation sur les performances du nouvel algorithme.Nous avons en outre étendu cette méthode pour prendre en compte les contraintes de borne par l’application d’une stratégie d’activation. Considérer une méthode avec ensemble actif pour l’optimisation basée sur des modèles d’interpolation donne la possibilité d’économiser une quantité importante d’évaluations de fonctions. Il permet de maintenir les ensembles d’interpolation plus petits tout en poursuivant l’optimisation dans des sous-espaces de dimension inférieure. L’algorithme résultant montre un comportement numérique très compétitif. Nous présentons des résultats sur un ensemble de problèmes-tests issu de la collection CUTEr et comparons notre méthode à des algorithmes de référence appartenant à différentes classes de méthodes d’OSD.Pour réaliser des expériences numériques qui intègrent le bruit, nous créons un ensemble de cas-tests bruités en ajoutant des perturbations à l’ensemble des problèmes sans bruit. Le choix des problèmes bruités a été guidé par le désir d’imiter les problèmes d’optimisation basés sur la simulation. Enfin, nous présentons des résultats sur une application réelle d’un problème de conception de forme d’une aile fourni par Airbus. / Derivative-free optimization (DFO) has enjoyed renewed interest over the past years, mostly motivated by the ever growing need to solve optimization problems defined by functions whose values are computed by simulation (e.g. engineering design, medical image restoration or groundwater supply).In the last few years, a number of derivative-free optimization methods have been developed and especially model-based trust-region methods have been shown to perform well.In this thesis, we present a new interpolation-based trust-region algorithm which shows to be efficient and globally convergent (in the sense that its convergence is guaranteed to a stationary point from arbitrary starting points). The new algorithm relies on the technique of self-correcting geometry proposed by Scheinberg and Toint [128] in 2009. In their theory, they advanced the understanding of the role of geometry in model-based DFO methods, in our work, we improve the efficiency of their method while maintaining its good theoretical convergence properties. We further examine the influence of different types of interpolation models on the performance of the new algorithm.Furthermore, we extended this method to handle bound constraints by applying an active-set strategy. Considering an active-set method in bound-constrained model-based optimization creates the opportunity of saving a substantial amount of function evaluations. It allows to maintain smaller interpolation sets while proceeding optimization in lower dimensional subspaces. The resulting algorithm is shown to be numerically highly competitive. We present results on a test set of smooth problems from the CUTEr collection and compare to well-known state-of-the-art packages from different classes of DFO methods.To report numerical experiments incorporating noise, we create a test set of noisy problems by adding perturbations to the set of smooth problems. The choice of noisy problems was guided by a desire to mimic simulation-based optimization problems. Finally, we will present results on a real-life application of a wing-shape design problem provided by Airbus.

Thesis is devoted to basic aspects of the reporting of financial derivatives. Mentioned is brief history and determination of term "derivative" from different points of view. Follows diversification of financial derivatives into groups. The main part is focused on reporting of fixed term contracts and options. Finally is described approach of International Financial Reporting Standards.

O objetivo deste trabalho é apresentar o cálculo das partições para espaços topológicos. Essa área trata do estudo de resultados do seguinte tipo: \"dados os espaços topológicos X e Y, um número natural n e um cardinal kappa, para qualquer que seja a partição de [X]^n em kappa pedaços, existe um subespaço H de X homeomorfo ao Y tal que [H]^n está contido num mesmo pedaço\". Iremos estudar esse tipo de afirmação, principalmente no caso em que n = 1 e Y é igual a um ordinal enumerável ou igual ao omega_1. Também veremos resultados que envolvem o cubo de Cantor. / The purpose of this work is to present the partition calculus for topological spaces. This area deals with the study of results of the following type: \"given the topological spaces X and Y, a natural number n and a cardinal number kappa, for whatever the partition of [X]^n into kappa pieces, there is a subspace H of X homeomorphic to Y such that [H]^n is contained in the same piece\". We will study results of this type mainly in the case where n = 1 and Y is a countable ordinal or the omega_1. We will also see results involving the Cantor cube.

A acne é uma doença de pele com alta prevalência e seu tratamento é importante para evitar lesões cutâneas permanentes ou o agravamento de transtornos psicológicos provenientes do abalo à autoestima. Dessa forma, o desenvolvimento de formulações dermocosméticas eficazes que possam melhorar as condições desse tipo de pele é de grande valia. Dentre os ativos com potenciais benefícios para o controle de alguns dos principais fatores causadores da acne, estão a vitamina B3, um derivado de vitamina B6 e o PCA zinco. Assim o objetivo deste estudo foi o desenvolvimento de formulações dermocosméticas para a pele acnéica contendo vitamina B3, derivado lipossolúvel de vitamina B6 e PCA zinco bem como a avaliação da estabilidade e eficácia clínica dessas formulações. Para tal, foram desenvolvidas diferentes formulações, as quais, em um primeiro momento, foram avaliadas quanto à estabilidade frente à adição do ingrediente ativo Zinc PCA. Após esta etapa, os demais ingredientes ativos foram adicionados e as formulações foram submetidas a testes preliminares de estabilidade e ao estudo da estabilidade física por determinação do comportamento reológico. A formulação mais estável foi avaliada quanto à compatibilidade cutânea e também em relação à comedogenicidade do veículo. A formulação composta pelos ingredientes ativos foi avaliada, ainda, quanto as suas características sensoriais e eficácia clínica. Os estudos de eficácia foram realizados por meio de métodos objetivos e subjetivos, após seis semanas do uso da formulação. Os métodos objetivos consistiram no uso de metodologias in vivo, não invasivas (métodos biofísicos e de imagem), sendo avaliados parâmetros relacionados à hidratação, função barreira, conteúdo lipídico, pH cutâneo, contagem de porfirinas, de microcomedões e de lesões inflamatórias. Em relação aos métodos subjetivos, foi realizada a percepção da eficácia por meio de um questionário para a comparação da pele antes e após o tratamento. Os resultados mostraram que, de todas as formulações desenvolvidas, apenas uma mostrou-se estável frente aos testes de estabilidade realizados. A formulação (veículo e adicionada de ingredientes ativos) apresentou compatibilidade cutânea considerada como \"muito boa\", de acordo com o teste realizado, e o veículo sem potencial comedogênico. Na avaliação sensorial as frequências obtidas para os parâmetros considerados como ruins foram baixas, indicando que o sensorial da formulação mostrou-se adequado para as finalidades propostas. No estudo de eficácia clínica, a formulação não alterou a hidratação e a função barreira da pele e mostrou-se eficaz na redução da contagem de porfirinas e das lesões inflamatórias (p<0,05). A avaliação clínica por métodos subjetivos mostrou a eficácia da formulação quanto à melhora da acne inflamatória, oleosidade da pele, hidratação e maciez. Por fim, os resultados obtidos mostraram que a formulação desenvolvida é eficaz e compatível com a pele, bem como a importância da pesquisa e desenvolvimento para a obtenção de formulações estáveis, seguras, eficazes e com sensorial adequado. / Acne is a skin disease with high prevalence and its treatment is important to prevent permanent skin lesions or the aggravation of psychological disorders due to self-esteem shaken. This way, the development of effective dermocosmetic formulations, that can improve the conditions of this skin type, is very important. Vitamin B3, a vitamin B6 derivative and zinc PCA are among the active ingredients which present potential benefits in the controlling of some pathogenic factors of acne. Thus, the aim of this research was to develop cosmetic formulations for acneic skin containing vitamin B3, vitamin B6 lipophilic derivative and zinc PCA, as well as the evaluation of stability and clinical efficacy. For this purpose, were developed different formulations which, at first, were evaluated in terms of stability face to zinc PCA addition. After this, the others active ingredients were added and the formulations were submitted to preliminary tests of stability and physical stability studies by rheological behavior determination. The most stable formulation was subject to skin compatibility evaluation and vehicle comedogenicity. The formulation with the active ingredients was also evaluated regarding their sensorial characteristics and clinical efficacy. Efficacy studies were performed by means of objective and subjective methods, after a sixweek- period of use of the formulation. The objective methods consisted in non-invasive in vivo methodologies (biophysical techniques and image analysis) where were evaluated hydration, barrier function, lipid content, skin pH and the counting of porphyrins, microcomedones and inflammatories lesions. In relation to subjective methods, was performed the efficacy perception using a questionnaire in order to compare the skin before and after the treatment. The results showed that among the formulations developed, only one kept stable after the stability tests. The formulations were considered as \"very good\" on skin compatibility test and showed no comedogenic potential. In sensorial evaluation, frequencies obtained for the parameters considered bad were low, which indicate the sensorial of the formulation was adequate for the purposes. In clinical efficacy study, the formulation under study did not alter the parameters related to hydration and skin barrier function and was effective in reducing the counting of porphyrins and inflammatories lesions (p<0,05). Clinical evaluation by subjective methods showed the formulation effectiveness regarding the improvement of inflammatory acne, skin oiliness, hydration and softness. Finally, the results obtained showed the formulation developed is effective and compatible with the skin and, besides the importance of research and development for obtaining stable, safe and effective formulations with suitable sensorial.

Esta dissertação revisa a literatura acadêmica existente sobre a teoria de opções utilizando os modelos de precificação com saltos. Os conceitos foram equalizados, a nomenclatura foi padronizada, sendo gerado um material de referência sobre o assunto. O pressuposto de lognormalidade com volatilidade constante não é aceito pelo mercado financeiro. É freqüente, no meio acadêmico, a busca de modelos que reproduzam os fenômenos observados de leptocurtose ou assimetria dos log-retornos financeiros e que possuam a mesma robustez e facilidade para manipulação analítica do consagrado modelo de Black-Scholes. Os modelos com saltos são uma alternativa para esse problema. Avaliou-se o modelo de Kou no mercado acionário brasileiro composto por um componente de difusão que segue um movimento browniano geométrico e um componente de saltos que segue um processo de Poisson com intensidade do salto descrito por uma distribuição duplamente exponencial. A simulação histórica do modelo aponta, em geral, uma superioridade preditiva do modelo, porém as dificuldades de calibração dos parâmetros e de hedge em mercados incompletos são as principais deficiências para o uso dos modelos com saltos. / This master dissertation reviews the academic literature about option pricing and hedging with jumps. The theory was equalized and the notation was standardized, becoming this document a reference document about this subject. The log-normality with constant volatility is not accepted by the market. Academics search consistent models with the same analytical capabilities like Black-Scholes? model which can support the observed leptokurtosis or asymmetry of the financial daily log-returns behavior. The jump models are an alternative to these issues. The Kou?s model was evaluated and this one consists of two parts: the first part being continuous and following a geometric Brownian motion and the second being a jump process with its jump intensity defined by a double exponential distribution. The model backtesting showed a better predictive performance of the Kou´s model against other models. However, there are some handicaps regarding to the parameters calibration and hedging.

Considerando o melanoma a forma mais agressivas de câncer de pele e mais resistente aos tratamentos convencionais, o presente estudo teve como objetivo avaliar a atividade de um novo complexo de platina (II) com derivado de hidantoína (CX42) em células de melanoma humano e murino. Foram utilizados também para comparação células da pele (fibroblastos, queratinócitos e melanócitos) e os compostos cisplatina (CIS) e complexo de hidantoína isolado (NN10). Ensaios de viabilidade, ciclo e morte celular foram realizados. Investigou-se também a atividade da enzima tirosinase, principal enzima que regula a síntese de melanina durante o processo conhecido como melanogênese. Como resultados, obteve-se a diminuição da viabilidade celular e parada de ciclo na fase G0/G1 nas células de melanoma, principalmente na linhagem murina B16F10, frente ao composto CX42. Em células B16F10, foi possível observar estímulo na melanogênese, com aumento da atividade da enzima tirosinase. O CX42 apresentou uma atividade com efeito citostático nas células de melanoma, não sendo observado efeito citotóxico nas células da pele. Ainda, com a prévia estimulação da melanogênese, o CX42 apresentou-se mais efetivo, aumentando a morte celular em 40% por apoptose. Portanto, conclui-se que o CX42 diminuiu a viabilidade celular e seu efeito foi mais intenso quando as células apresentavam-se pigmentadas, demonstrando indução da tirosinase e da morte celular, atributo importante para potenciais novos fármacos anti-melanoma. / Since melanoma is one of the most aggressive forms of skin cancer and more resistant to conventional treatments, the present study aimed to evaluate the activity of a new platinum complex (II) with hydantoin derivative (CX42) in melanoma cells human and murine. Skin cells (fibroblasts, keratinocytes and melanocytes) were used as control and the compounds cisplatin (CIS) and hydantoin compound alone (NN10) were also evaluated. Viability assays, cell cycle analysis and cell death characterization were performed. Likewise, the activity of tyrosinase, the key enzyme that regulates melanin synthesis during the process known as melanogenesis, was also investigated. The results demonstrated a reduction in cell viability and cell cycle arrest in G0/G1 phase of murine melanoma B16F10 treated with CX42. In B16F10 cells, it was also observed melanogenesis stimulation with increased activity of tyrosinase. The CX42 showed a selective cytostatic effect on melanoma cells, however no toxic effects were observed in skin cells. In addition, with prior stimulation of melanogenesis, the CX42 demonstrated to be more effective, increasing apoptosis cell death in 40%. Therefore, the results demonstrated that CX42 decreased cell viability and the intensity of its effect is associated with cell pigmentation, demonstrating an association between tyrosinase high activity and induction of cell death which is an important attribute for new potential anti - tumoral drugs.

A zidovudina (AZT) ainda é o fármaco mais empregado no tratamento da AIDS, isoladamente ou em associação a outros antirretrovirais, porém é um fármaco administrado em altas doses e que apresenta efeitos adversos que comprometem a adesão do paciente ao tratamento. Assim, um novo sistema de liberação de zidovudina composto por nanopartículas de poli (n-butil-cianoacrilato) (PBCA) revestidas por ácido hialurônico (AH) foi desenvolvido e caracterizado com o objetivo de prolongar a liberação do fármaco e diminuir sua toxicidade. As nanopartículas têm sido amplamente estudadas como veículo para fármacos por permanecer na circulação por um tempo maior e, portanto, liberar o fármaco de forma prolongada. Para polimerização e, portanto, obtenção das nanopartículas, n-butil-cianoacrilato e Dextran® foram adicionados a HCl 0,1 M (pH 2,5), sob agitação a 800 rpm, por 1 h. O AZT foi adicionado e o processo foi neutralizado com adição de NaOH 0,1M após mais 3 h de agitação. Após filtração as partículas foram revestidas pela adição de uma dispersão aquosa de ácido hialurônico (AH) a baixa rotação. O diâmetro hidrodinâmico médio das nanopartículas não revestidas foi de 152,3 nm, com um índice de polidispersividade médio igual a 0,055. O potencial zeta médio dessas partículas foi -0,678 mV. O diâmetro hidrodinâmico médio das nanopartículas revestidas com AH obtido foi de 196,9 nm, com um índice de polidispersividade médio igual a 0,440. O potencial zeta médio dessas partículas foi de -25,6 mV. Os valores resultantes dessas análises são indicativos da estabilidade das nanopartículas obtidas e da boa reatividade dos monômeros dos cianoacrilatos. Ainda, pelos resultados é possível confirmar a ocorrência do revestimento. Assim, a eficiência do processo de revestimento das nanopartículas pode ser comprovada por meio dos resultados das análises de calorimetria exploratória diferencial (DSC) e pelos resultados das análises de espectroscopia de absorção na região do infravermelho. Para quantificar o fármaco associado às nanopartículas, um método empregando espectrofotometria derivada (ED1) no UV aplicando a técnica do ponto de anulação foi desenvolvido e validado. Tal método possibilitou a eliminação da interferência dos excipientes, o que permitiu a quantificação do AZT na suspensão de nanopartículas com precisão e exatidão adequadas. A porcentagem de fármaco associado às nanoestruturas obtidas pelo método foi de 64%, considerado satisfatório. As nanopartículas foram incorporadas a uma formulação base de gel de Carbopol® 940 que, apresentou estabilidade após ser submetida a diferentes condições de armazenamento, com incidência de luz e variação da temperatura. / Zidovudine (AZT) is still the most widely used drug in the treatment of AIDS, alone or in combination with other antiretroviral drugs, however it is indicated in high doses and has adverse effects that compromise patient compliance to treatment. Thus, a new zidovudine delivery system made of poly (n-butyl-cyanoacrylate) nanoparticles coated with hyaluronic acid (HA) was developed and characterized in order to extend the drug release and reduce its toxicity. The nanoparticles have been widely studied as drug carriers once they remain in circulation for a longer period and, consequently, release the drug gradually. For the polymerization, and, therefore synthesis of nanoparticles, n-butyl-cyanoacrylate and Dextran® were added to 0.1 M HCl (pH 2.5) and stirred at 800 rpm for 1 hour. AZT was added and the reaction was neutralized by the addition of 0.1 M NaOH after 3 more hours of agitation. After filtration the particles were coated by addition of an aqueous dispersion of hyaluronic acid (HA) at low revs. The mean hydrodynamic diameter of non-coated nanoparticles was 152.3 nm with an average polydispersity index of 0.055. The average zeta potential of these particles was -0.678 mV. The average hydrodynamic diameter of the coated nanoparticles was 196.9 nm, presenting an average polydispersity index of 0.440. The average zeta potential of these particles was -25.6 mV. The resulting values of these tests are indicative not only of the stability of the obtained nanoparticles but also the good reactivity of the monomers of cyanoacrylates. Moreover, the results can confirm the occurrence of coating. Thus, the efficiency of the coating process of the nanoparticles can be demonstrated by the results of the analysis of differential scanning calorimetry (DSC) and the results of the absorption spectroscopy in the infrared region. In order to quantify the drug associated with the nanoparticles, a method employing derivative spectrophotometry (ED1) UV applying the zero-crossing technique was developed and validated. This method allowed the elimination of interference of excipientes, allowing the quantification of AZT nanoparticles in suspension with adequate accuracy and precision. The percentage of the drug associated with the obtained nanostructures by the method was 64%. The nanoparticles were incorporated into a Carbopol® 940 gel formulation, which was stable after being subjected to different storage conditions, with incidence of light and temperature variation.

Submitted by Elba Lopes (elba.lopes@fecap.br) on 2016-02-04T15:01:00Z No. of bitstreams: 2 Clemil_Robles.pdf: 1063090 bytes, checksum: c8a8fbf9e8a0e811b0f4268c4a413a6d (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2016-02-04T15:01:00Z (GMT). No. of bitstreams: 2 Clemil_Robles.pdf: 1063090 bytes, checksum: c8a8fbf9e8a0e811b0f4268c4a413a6d (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2003-01-15 / The purpose of this work is to research and compare accounting rules emanated from the FASB and from the Brazilian Central Bank applied to Derivatives. The fact that financial institutions run popular savings funds and the fact that they also represent an important link between several economic agents , enhances the importance of the performance and of the stability of the financial system. The activity of the financial institutions involve several risks which can lead to the insolvency and consequently the ruin of the popular savings. The use of transactions with derivatives by financial institutions as hedging of the operations themselves and for speculation, have become more popular over the years. Therefore it is of utmost importance to know risks those financial institutions run when they carry out said transactions and also how those risks are being dealt with, accounted for and evidenced to their clients. In this work we have tried to compare the accounting rules, apart from evidencing that transactions with derivatives have been carried out according to the international standards. The survey concluded that the Brazilian accounting system derived from the Brazilian Central Bank resembles those of IASB and FASB. Therefore it has been evidenced that those entities outside the scope of the Central Bank, do not possess accounting rules which deal adequately with operations with derivatives. / O prop??sito deste trabalho ?? pesquisar e comparar as normas cont??beis emanadas do FASB (Financial Accounting Standards Board), IASB (International Accounting Standards Board) e do Banco Central do Brasil aplicadas a derivativos. O fato de as institui????es financeiras administrarem recursos da poupan??a popular e de representarem importante elo entre os diversos agentes econ??micos faz com que o desempenho e a estabilidade do sistema financeiro assumam particular relev??ncia, pois a atividade das institui????es financeiras envolve diversos riscos, que podem resultar na sua insolv??ncia e, conseq??entemente, na destrui????o de poupan??a popular. A utiliza????o de opera????es com derivativos pelas institui????es financeiras, que s??o realizadas para fins de hedging das pr??prias opera????es e para especula????o, t??m se acentuado nos ??ltimos anos. Portanto, conhecer os riscos a que essas entidades est??o expostas ao fazerem essas opera????es e como tais riscos est??o sendo gerenciados, contabilizados e evidenciados aos usu??rios ?? de suma import??ncia. Procurou-se no presente trabalho, al??m de comparar as normas cont??beis, efetuar a constata????o de que as opera????es com derivativos das institui????es financeiras brasileiras est??o seguindo o tratamento cont??bil, julgado adequado, pelos principais organismos internacionais normatizadores de regras cont??beis. A pesquisa conclui que o arcabou??o cont??bil brasileiro emanado do Banco Central do Brasil, possui grande similaridade com as normas do IASB e FASB. Por??m, constatou-se que as entidades fora do ??mbito de atua????o do Banco Central n??o possuem normas cont??beis que d??em tratamento adequado ??s opera????es com derivativos.

Submitted by Maria Cristina (library@lncc.br) on 2017-05-02T18:47:49Z No. of bitstreams: 1 Tese_Machado.pdf: 522761 bytes, checksum: 871b43ac7f8d7aae60a30b8371cf5898 (MD5) / Approved for entry into archive by Maria Cristina (library@lncc.br) on 2017-05-02T18:47:59Z (GMT) No. of bitstreams: 1 Tese_Machado.pdf: 522761 bytes, checksum: 871b43ac7f8d7aae60a30b8371cf5898 (MD5) / Made available in DSpace on 2017-05-02T18:48:08Z (GMT). No. of bitstreams: 1 Tese_Machado.pdf: 522761 bytes, checksum: 871b43ac7f8d7aae60a30b8371cf5898 (MD5) Previous issue date: 2017-02-09 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (Capes) / In structural optimization, the obtained results must be robust in relation to uncertainties, whether they arise from the probabilistic nature of the variables or those inherent to the resistance of the materials, for example. Traditionally, uncertainties in structural design were taken into account by using safety factors. Nevertheless, it is well known that the safety factor approach can be limited in a wide variety of cases or yields to conservative designs. For this reason, several authors proposed different approaches to address optimization problems subject to uncertainties, such as robust topology optimization and reliability-based topology optimization. In this work, we present an alternative approach for robust topology optimization considering a point-wise worst case scenario. We also study reliability-based structural topology optimization problem under stress constraints. In addition, in order to apply an approach for uncertainty based optimization into a non-linear problem, we investigate the deterministic structural topology optimization problem subject to unilateral contact condition. / Em otimização estrutural os resultados obtidos devem ser robustos em relação a incertezas, sejam elas oriundas da natureza probabilística das variáveis de trabalho ou àquelas inerentes à resistência dos materiais, por exemplo. Classicamente, levar em conta incertezas em um projeto de estruturas significa utilizar um fator de segurança. No entanto, tal abordagem pode ser bastante restritiva em uma grande variedade de casos ou ainda conduzir a resultados muito conservadores. Este fato tem levado ao desenvolvimento de diferentes metodologias de otimização estrutural tais como otimização robusta e otimização baseada em confiabilidade. Neste trabalho objetiva-se apresentar uma abordagem alternativa para o problema de otimização robusta de estruturas levando em consideração otimização no pior cenário, além de estudar o problema de otimização topológica estrutural baseada em confiabilidade com restrição em tensão. Além disso, a fim de aplicar técnicas de otimização considerando incertezas num problema não linear é estudado o problema determinístico de otimização topológica de estruturas sujeitas a condição de contato unilatera