L’objectif de cette thèse est de répondre au besoin d’accélérer la restitution des résultats de calcul d’un code CFD pour la simulation d’écoulements hydrodynamiques quasi-incompressibles. Ce code présente l’originalité de résoudre explicitement les équations de Navier-Stokes sous l’hypothèse de faible compressibilité avec des schémas numériques d’ordre élevé. Les développements effectués visent à réduire les temps de calcul à précision équivalente.Une première partie est consacrée à l’implémentation d’une formulation purement incompressible avec une résolution implicite de la pression par un schéma de projection. La formulation incompressible autorise des pas de temps plus grand en s’affranchissant de la vitesse du son, mais au prix d’une algorithmique plus complexe et de la nécessité de résoudre un système linéaire. La comparaison des deux formulations,faiblement-compressible et incompressible, tend à montrer la pertinence du schéma de projection pour les écoulements laminaires instationnaires.Un deuxième axe de développement a consisté en la proposition d’une amélioration de la méthode de frontière immergée initialement présente dans le code.Si les résultats obtenus ne sont pas encore pleinement satisfaisants, ils montrent que la montée en ordre d’une méthode de frontière immergée peut être moins contraignante en formulation incompressible.Enfin la dernière partie traite de l’immersion rapide et robuste de géométries complexes telles qu’elles peuvent être rencontrées dans l’industrie. La localisation géométrique par arbre octal permet d’évaluer rapidement une fonction de distance signée indispensable pour la méthode de frontière immergée. / An original strategy to address hydrodynamic flow was recently proposed through a high-order weakly-compressible Cartesian grid approach. The method is based on a fully-explicit temporal scheme for solving the Navier-Stokes equations. The present thesis aims to reduce the computational time required to obtain the results without deteriorating the accuracy.A first part is dedicated to the implementation of a truly incompressible formulation with an implicit solution for the pressure field through a projection scheme. The incompressible solver allows larger time step size for time integration since the speed of sound tends to infinity. In return the algorithms are no longer straight forward and a linear system has to be solved through the Pressure Poisson Equation. Comparisons carried out between both formulations show that the projection scheme can be better adapted to efficiently simulate unsteady viscous flows. Then an improvement of the immersed boundary method has been proposed. Results are not fully satisfactory for now. However, it seems easier to develop a numerical scheme for the incompressible approach rather than the weakly-compressible one.Finally, the last part addresses the setup up of complex triangulations in immersed boundary simulations. A fast and robust procedure is developed for distance computation with an octree data structure.

O presente trabalho teve, por objetivo, caracterizar a indústria de refino de açúcar no Brasil e identificar o modelo de comportamento da concentração de mercado da referida indústria para a região Centro-Sul do Brasil. Procurou-se analisar a influência dos distintos níveis de competição via preço e barreiras à entrada sobre a sua estrutura de mercado. Também foram analisadas a influência de fatores exógenos, como intervenção do governo, organização setorial e estratégias empresariais, na determinação da concentração de mercado do setor; o valor das barreiras à entrada para uma indústria média, baseada na análise da escala mínima eficiente de produção. Para tanto, utilizou-se o modelo teórico desenvolvido por Sutton (1991), que é o modelo do jogo de dois estágios para indústrias intensivas em sunk cost exógenos. Compararamse os resultados com os encontrados pelo autor para a Europa, o Japão, os Estados Unidos e Taiwan. Para tanto, definiu-se o mercado relevante como a região Centro-Sul do Brasil e calcularam-se a razão de concentração da referida indústria e a razão entre tamanho de mercado e nível de sunk cost exógeno. O valor encontrado para 2001 (σ/S igual a 0,8407%) é condizente com os dos países analisados por Sutton, que evidenciam o alto índice de custos irrecuperáveis e a existência de barreiras à entrada e explicam a estrutura de mercado encontrada. Verificou-se que a indústria de refino de açúcar no Brasil, inicialmente, foi construída por pequenos e médios grupos comerciais, com intensa atividade regional, sendo o setor regionalmente concentrado. Durante a fase de intervenção, destaca-se o forte caráter concentrado da indústria, apresentando na década de 1980, o CR4 da indústria de cerca de 80%. Nas décadas de 1990 e 2000, houve o crescimento e o surgimento de marcas menores, ao mesmo tempo em que a marca líder (União) teve reduzida sua importância no total das vendas do setor. Um dos elementos que explicam o forte caráter concentrado da indústria são as barreiras à entrada no setor: assim como as indústrias de açúcar refinado dos países analisados, a indústria de açúcar refinado do Brasil apresenta, de acordo com dados calculados para o ano 2003, alta barreira à entrada, em relação ao tamanho do mercado. No entanto, se, por um lado, a indústria apresenta elevados índices de concentração, por outro, acredita-se que os produtores de açúcar refinado não possam se utilizar desse poder de mercado junto aos consumidores. Os preços internos sofrem grande influência do mercado internacional, além da forte pressão do varejo supermercadista, também concentrado. Verificou-se que os preços descendentes ao longo do tempo são positivamente relacionados com a evolução da estrutura de mercado do período analisado. / The aim of the present work was to evaluate the refined sugar industryin Brazil and to identify its market behavior in the central region in Southern Brazil Accordingly, this study analyzed the influence of distinct levels of competition concerning price and entrance barriers on the market structure. Some exogenous factors, such as public regulation, sectorial organization, and strategies to set up costs, were also verified to determine the market sector’s concentration. the theoretical model of two-stage game for industries intensive in exogenous sunk cost described by Sutton (1991) was used to determine the value of the set up costs for a single plant of minimum efficient scale (m.e.s). Data of the present study were compared to those reported by Sutton (1991), whose study focused on Europe, Japan, United States and Taiwan. The present work, however, focused on the central region in Southern Brazil. The ratio of the market concentration of the sugar-refining industry, as well as the ratio of its market size and exogenous sunk cost was calculated. The value of σ/S found for 2001 was 0.8407%, consistent with the values found for the countries analyzed by Sutton; furthermore, this result evidences the high index of set up costs and existence of barriers of entrance, suggesting that that the industry of refining sugar in Brazil was initiated with small and average commercial groups, with a regionally-concentrated sector. During the regulated period the industry was highly concentrated (by the 1980s the CR4 was about 80%). In the 1990s, there was a great entrance of new brands and consequently a decline in the leader brand (União). One of the reasons that such industry is highly concentrated is the huge sunk cost. Like the refined sugar industry analyzed in other countries, the Brazilian refined sugar industry presented, in 2003, high exogenous sunk cost in relation to the size market.

Dada a complexidade hidrodinâmica de escoamentos gás-sólidos em leitos fluidizados muitas pesquisas têm sido realizadas abordando questões relativas a natureza altamente instável desse processo de fluidização. O conhecimento dessa hidrodinâmica permite estabelecer os parâmetros corretos para reação e transporte de massa em um reator de leito fluidizado, permitindo tomada de decisões à respeito do desempenho do reator. Modelos Eulerianos do contínuo, onde as fases coexistentes são tratadas como meios contínuos interpenetrantes, representam a aproximação mais prática para simular a hidrodinâmica de escoamentos gás-sólido em reatores de leito fluidizado. Aplicando-se procedimentos de médias de Euler obtêm-se os modelos hidrodinâmicos A e B desenvolvidos por GIDASPOW [27] do IIT/ANL, representando as equações conservativas e constitutivas de modelos de duas fases separadas para escoamentos gás-sólido. Neste trabalho, aplica-se um modelo Euleriano de duas fases separadas, desenvolvendo simulações numéricas para diferentes dimensões de colunas ascendentes de leito fluidizado circulante. Para resolução das equações discretas no domínio bidimensional, aplicam-se malhas refinadas. Analisam-se os efeitos nos resultados de simulação causados por essas malhas. Apresenta-se uma discussão geral sobre o modelo aplicado em torno dos resultados obtidos. / Due to the hydrodynamic complexity of gas-solid flows in fluidized beds, several researches have been conducted addressing issues concerning the highly unstable nature of this fluidization process. The knownledge of its hydrodynamics allows establishing the correct parameters for the reaction and mass transport in a fluidized bed reactor, improving its performance. Continuous Eulerian models, where the phases are treated as a continuum, represent the most practical approach to simulate the hydrodynamics of gas-solid flows in fluidized bed reactors. By applying Euler average procedures, it is possible to obtain the hydrodynamic models A and B, developed by GIDASPOW [27] at IIT/ANL. These models represent the conservative and constitutive equations for the models of two separate phases for gas-solid flows. In this work, an Eulerian two-fluids model is applied, developing numerical simulations for different risers of circulating fluidized bed. For the resolution of the discrete equations in the two-dimensional domain, refined meshes are used. An analysis of their effects on the results of the simulation is performed. A general discussion about the results obtained by the model applied is also presented.

O ano era 1912, e um imigrante italiano e um grupo de irmãos provindos da aristocracia fazendeira encontraram-se nos escritórios sobre o famoso Café Guarany, no pulsante coração comercial da cidade, o Triângulo, para combinarem os trâmites à fundação da primeira fábrica de louças em faiança fina do país, em moldes industriais, produção em série e larga escala, no, então, rural bairro da Lapa. Assim teve início a história da Fábrica de Louças Santa Catharina, posteriormente Indústrias Reunidas Fábricas Matarazzo (IRFM) - São Paulo, que abarrotou a cidade de São Paulo com toneladas de louças brancas ou decoradas feitas em seus inúmeros fornos. Fundada no fulcro dos projetos de modernização para a Paulicéia tão desvairada, fábrica e louças dialogaram com as conjunturas das quais eram agência e estrutura. Formas e motivos espalharam-se pelos diversos consumidores da cidade, desbancando, muitas vezes, o monopólio da louça branca estrangeira, da qual se diferenciou produzindo-se segundo lógicas e tecnologias locais. Esta pesquisa baseia-se na análise do sítio arqueológico Petybon, no bairro da Lapa, cidade de São Paulo, região da Água Branca/Vila Romana, escavado no ano de 2003, que revelou ter sido o local de uma antiga fábrica de louças em faiança fina, inaugurada em 1913, fundada meio à maciça imigração italiana e o financiamento das indústrias pelo capital do café. Funcionou até 1937, já pertencente aos Matarazzo que a adquiriram em 1927. O local tem extrema relevância não apenas no contexto da Arqueologia Urbana no Brasil, como também enquanto exemplar dos primórdios da industrialização do país e da história da produção da louça nacional, parcamente tratada pela literatura, pouco valorizada e identificada, apesar de sua freqüência nos sítios arqueológicos do século XX. / The year was 1912, and an Italian immigrant and a group of brothers, drawn from an Aristocratic family farmer, met at an office above the famous Guarany Coffee House, in the beating heart of the city, the Triangle, to establish a fellowship and combine the procedures to the foundation of the first refined earthenware factory in the country, based on an industrial manufacturing, by a mass and large scale production, at the rural district of Lapa. That was the beginning of the history of Santa Catharina Pottery Factory, later Matarazzo United Manufacturing - São Paulo, who crammed São Paulo city with tons of white or decorated pottery, made in its many kilns. Forged at the center of modernizations project for the city, the pottery and factory dialogue with the contexts whose were agency and structure. Forms and motifs spread out by various consumers, beating, often, the foreign pearlware and whiteware monopoly, from whom it was distinguished by organizing itself according with its own logic and technology development. This research is based on the analysis of Petybon archaeological site, in the neighborhood of Lapa, São Paulo, at the region known as Água Branca / Vila Romana, excavated in 2003, which appeared to have been the site of one of the firsts refined earthenware factories, opened at 1913, founded through the massive Italian immigration and the financing of industries by coffee profits. Worked until 1937, then belonging to the Matarazzo Family, who acquired it in 1927. The site is extremely important not only in the context of Brazilian Urban Archeology, but also as an example of the early industrialization in Brazil and the history of national pottery industry, barely treated by literature, almost unknown and unappreciated, despite its frequency at Brazilian archaeological site from the 20th century.

No description available.

中唐詩歌「由雅入俗」的美學意涵研究摘要： 本論文共七章。第一章「緒論」申明研究宗旨、研究範圍、研究方法。並對中唐年代作一界定，論述「雅」與「俗」的分野，以作為全文探討中唐詩歌「由雅入俗」趨勢的基礎。 第二章「中唐文人之階層變動及其生命意涵」。中唐詩歌開展由雅入俗美學思潮的原因，實肇於創作主體文人階層的內涵，已由以往依附帝王世族的文人，轉為憑藉學識才華入仕的士子。是以本章先釐析科舉制度對於文人的意義，論述以進士科為主的文人如何成為社會、政治上的新興勢力。作為新興士大夫階層的官吏或文人，也需要確定自己個人的人生理想或人生價值。本章從文人生命性格的形塑、社會地位的定格、歷史文化的追尋三個面向，由進而遠、由淺而深地求索中唐文人的生命意涵，考察中唐寒士文人自我意識增強的表現情形，發掘他們求新求變的心態導致時代美學觀念的變化，這也是讓詩歌由雅入俗的內在原因。 第三章「新樂府運動的革新意義與通俗化傾向」。新樂府運動是有唐一代最重要的詩歌改革運動。提倡者白居易和元稹代表的是新興庶族初登政治權力上層、滿懷理想的文人典型。新樂府運動以輔國匡君、濟民傷痛為宗旨，從根本上改變了過去文人側重吟詠個人內心世界的詩歌傳統。本章首節論述新樂府運動的形成過程，並探討它和古文運動的關係，第二節分析元白的詩歌理論見解，尤其突出詩人以文學改革時政的強烈企圖，第三節鑑賞詩歌作品，觀察其實踐理論之情形如何，最末一節則評論新樂府詩作通俗化的美學表現，包括：語言淺顯、句式多變；敘事詳盡、聞之即懂；詩體的散文化與議論化；以普遍人性為基本訴求等四點。 第四章「元白詩派的通俗詩風與生活化文化取向」，附文「劉禹錫與柳宗元詩中『尚俗』特色之考察」。元白詩派是中唐詩壇上兩大詩派之一，本章探討其通俗化的詩歌內涵。白居易和元稹的仕宦生涯一再遭逢無情的貶謫打擊，詩歌創作產生明顯的轉變：批判時局弊政、揭露民生困苦的內容驟然減少；抒發一己幽思，描寫日常生活瑣事的內容迅速增多。不變的是詩歌平易、淺切、通俗易懂的特色，仍貫串當中。本章第一節討論元白生命歷程的轉折，考求詩風轉變的原因，並論及他們詩歌唱和的情形，對「元和體」之意義作一界定。第二、三節分別探討艷情詩、閒適詩、感傷詩作品，釐析元白詩派後期詩作的具體內涵。第四節則分析詩歌趨向繪寫閒情俗趣的生活化特色，說明元白詩何以能在中唐當時空前流行，傳誦人口，造成當代詩歌普及化的現象。本章篇末附文為「劉禹錫與柳宗元詩中『尚俗』特色之考察」。中唐詩壇雖以元白、韓孟詩派為兩大詩歌主流，但又有劉禹錫、柳宗元兩位重要詩人別開生面，開創出絕然不同的詩歌藝術風格。附文即針對劉、柳詩作當中，趨向世俗化部分之特色加以論述分析，完整地考察並呈現中唐詩歌由雅入俗的風貌。 第五章「韓孟詩派獨特的抒情模式與由雅入俗的表現」。韓孟詩派與元白詩派並列中唐詩壇兩大詩派，它是以韓愈和孟郊為核心的一個詩人群體，在創作方法上搜奇抉怪，刻意出新；風格表現上險峭奧折、美醜並陳，涵孕出一股與眾不同的詩歌特色，緣於這種特色，又被稱為「險怪詩派」。本章第一節首先論述韓孟詩派的作家，包括韓愈、孟郊、盧仝、劉叉、馬異、李賀、賈島等人的性格與出身經歷，尋究詩派風格形成的內在原因。再者，他們專務奇險艱苦、幽冷寒僻的抒情方式，顯與以往詩歌「志之所之，詩亦至焉」的創作心態有所不同，本章第二節就韓孟詩派的抒情方式，作一剖析。第三節則集中論述韓孟詩派的詩歌內容及創作手法各方面由雅趨俗的表現。 第六章「中唐詩歌的美學特色」。中國詩歌向有唐宋之分。詩分唐宋，不只是時代的分別，還有風格的不同，唐詩重韻致，多能情景交融，高華清遠，雄渾豐腴；宋詩重理趣，多挺拔瘦勁，氣骨嶙峋。唐音宋調的不同，究其源頭即淵源於中唐。中唐之後，中國社會、文化也進入了新的發展階段。從宏觀的角度來看，政治結構乃至社會結構的變化，對知識階層的心理產生極大的影響，中唐文人於是在文學觀念、審美觀念上均與以往文人有所不同。中唐詩歌的變化，在於整體精神的由外向內，由典雅化趨向日常化與通俗化。而這種個人化、內心化、生活化的審美心理與美學風範，不但影響了宋代詩人，更是宋代之後文人士大夫最為典型的審美風範。本章首節論述中唐詩人主體意識的增強，從而改變了審美視角，擴大了審美範圍。第二節討論中唐文人對民間文學的廣闊吸納程度，包括他們直接參與填詞、寫小說等創作的情形。第三節探討中唐詩人在詩歌內涵融鑄宗教思想的狀況，他們往往在堅守儒家為本位的立場之餘，融入佛家與道家思想，調解他們在政治生活和精神生活中遭遇的苦悶與挫折，這種三教融和的人生觀，深深影響宋人。第四節則是就中唐詩歌由雅入俗的趨勢，作一整體評析。 第七章「結論」。依據以上各章之探討，總結要點，並就研究發現與成果，一一臚列以為結論。 / A Research of the Aesthetics Significances of Tang Poetry’s Shift from the Refined to the Popular Tastes The Dissertation is composed by seven chapters, giving a holistic analysis of the aesthetics significances of Tang Poetry’s shift from the refined to the popular tastes. The titles of the chapters are as followed: Chapter 1, ‘Introduction;’ Chapter 2, ‘Social Classes’ Shift and its Significances of the Scholars in Mid-Tang Dynasty;’ Chapter 3, ‘Revolutionary Significances of the New Yuei-Fu Movement and its Tendency toward Popular Tastes;’ Chapter 4, ‘Popular Tastes in the School of Yuan Jan and Bai Jui-Ye’s Poetry And Its Tendency of Allocating Daily-Life Aspects;’ Chapter 5, ‘The Uniqueness of the Poetry-writing Approaches and the Popularization in the School of Han Yu and Mong Jiau;’ Chapter 6, ‘Aesthetics Significances of the Mid-Tang’s Poetry and its historical meaning in the Chinese Poetry History;’ Chapter 7, ‘Conclusion.’ Two appendixes are included in the Dissertation: Appendix 1, ‘Aesthetics Paradigm Shift of Mid-Tang Poetry;’ and Appendix 2, ‘Bibliography of the Mid-Tang Poets.’

Made available in DSpace on 2016-06-02T19:55:37Z (GMT). No. of bitstreams: 1 5587.pdf: 3066852 bytes, checksum: 17d88d3ab913d61bb315842b57ec5a74 (MD5) Previous issue date: 2013-09-30 / Universidade Federal de Sao Carlos / Cyclones are used to separate suspended particles from gas streams. The analysis of flow inside the cyclone is complex due to the large number of parameters and operating variables that influence the dynamics of the system. Due to its versatility of use and its robustness, results in computational fluid dynamic are an important alternative often used to study the dynamics of flow in the cyclone. In the literature, several works make use of computational fluid dynamics in order to study the pressure drop of cyclones. However, the works about the efficiency of collection are fewer. For the cyclone, computational fluid dynamics allows an accurately simulation of the collection efficiency of particles with diameter greater than 5 µm; but for particles with smaller diameters the simulated results diverge from experimental values. In this work, Stairmand s cyclone was numerically simulated with injected particles with diameters from 1 to 5 µm. The results were verified using available experimental data reported in the literature. The experimental data taken from literature belong to Zhao and Shen Kang (2004) and Zhao (2005). The simulation mesh was analyzed before and after the simulations. The turbulence models used in the simulation of flow in the cyclone were: Reynolds Stress Model (RSM) and Large Eddy Simulation (LES). The dispersed phase was simulated considering one and two way couplings. The equation of motion of the particles was integrated using the integration schemes: implicit, analytic, trapezoidal, and Runge-Kutta. The results showed that the methodology was adequate to reproduce the behavior of the flow in the cyclone. The error percentages obtained in pressure drop were under 5% and the average collection efficiency was reproduced with good accuracy for diameters of 3, 4 and 5 µm. / O ciclone é um equipamento utilizado para separar partículas suspensas em correntes gasosas. A análise do escoamento dentro do ciclone é complexa devido ao grande número de parâmetros e variáveis operacionais que influenciam na dinâmica do sistema. Devido a sua versatilidade de uso e a sua robustez nos resultados a fluidodinâmica computacional é uma alternativa importante utilizada com frequência no estudo da dinâmica do escoamento no ciclone. Na literatura existem vários trabalhos que fazem uso da fluidodinâmica computacional no estudo da queda de pressão. Entretanto, no estudo da eficiência de coleta, os artigos são em menor quantidade. No ciclone, a fluidodinâmica computacional permite simular a eficiência de coleta de partículas com diâmetro maiores que 5 µm com bastante precisão; a modelagem da eficiência de coleta para partículas com diâmetros menores ainda resultam em valores diferentes dos valores experimentais. Neste trabalho foram realizadas as simulações numéricas no ciclone tipo Stairmand; foram injetadas partículas de 1 a 5 µm. Para a verificação foram tomados dados experimentais disponíveis na literatura. Os dados experimentais foram obtidos por Zhao, Shen e Kang (2004) e Zhao (2005). A malha utilizada nas simulações, foi analisada antes e depois das simulações. Os modelos de turbulência utilizados para simular o escoamento no ciclone foram: Reynolds Stress Model (RSM) e Large Eddy Simulation (LES). A fase dispersa foi simulada considerando acoplamento de uma via e acoplamento de duas vias. Para integrar as equações de movimento das partículas, foram utilizados os esquemas de integração: implícito, analítico, trapezoidal e Runge-Kutta. Os resultados mostraram que a metodologia empregada mostrou-se adequada para reproduzir o comportamento do escoamento no ciclone. As porcentagens de erro obtidos na queda de pressão foram em média menores que 5% e na eficiência de coleta foram reproduzidas com boa precisão para os diâmetros de 3, 4 e 5 µm.

Submitted by Lorenzo Pieri (lpieri@ymail.com) on 2013-07-01T22:47:18Z No. of bitstreams: 1 EPGEFGV_Dissertacao_Pieri_Lorenzo_FINAL.pdf: 21467835 bytes, checksum: 660c8bb8775579959cc7d94bb71d0a0a (MD5) / Approved for entry into archive by Vitor Souza (vitor.souza@fgv.br) on 2013-07-11T17:43:27Z (GMT) No. of bitstreams: 1 EPGEFGV_Dissertacao_Pieri_Lorenzo_FINAL.pdf: 21467835 bytes, checksum: 660c8bb8775579959cc7d94bb71d0a0a (MD5) / Made available in DSpace on 2013-07-19T13:44:55Z (GMT). No. of bitstreams: 1 EPGEFGV_Dissertacao_Pieri_Lorenzo_FINAL.pdf: 21467835 bytes, checksum: 660c8bb8775579959cc7d94bb71d0a0a (MD5) Previous issue date: 2013-04-19 / Through an Error Correction Model this study explores possible asymmetries in the passthrough of the oil prices to gasoline and diesel prices in the US market and, mainly, analyzes if the trends reversals of those refined oil products demand at the above market affected the price transmission mechanism. Using monthly date from January 2001 to December 2012, the results for gasoline indicated that there was evidence of passthrough due to the demand shift. However, it is worth noting that this result occurred concurrently with the period of recovery in prices witnessed after the 2008 crisis. Regarding diesel, there is no evidence that there were changes in the passthrough. Finally, we found evidence of the WTI decline as an oil reference due to its devaluation from 2010. / Através de um Modelo de Correção de Erros este estudo explora possíveis assimetrias no passthrough dos preços de petróleos para os preços do diesel e da gasolina no mercado dos Estados Unidos, analisando, principalmente, se as inversões das tendências das demandas destes derivados afetaram o mecanismo de transmissão de preços. A partir de dados mensais de janeiro de 2001 a dezembro de 2012, para a gasolina foram encontrados indícios de que houve alterações do passthrough em decorrência da quebra da demanda. Porém, é válido destacar que tal resultado ocorreu concomitantemente ao período de recuperação de preços presenciada após a crise de 2008. Em relação ao diesel, não há indícios de que houve alterações no passthrough. Por fim, há evidências da redução do WTI como petróleo de referência em decorrência da sua desvalorização a partir de 2010.

Governments across the globe are experiencing enormous budget deficits. The governments of South Africa and Australia felt that taxes on mining have not been reflecting a ‘willing buyer-willing seller’ relationship. This in essence means that mining companies in these two countries were not paying an arm’s length value to governments for extracting the resources. In Australia the authorities introduced the Resources Super Profits Tax to be charged at 40% of assessable profits. Mining companies still have to assess how to deal with this new tax when it is enacted on 1 July 2012. However, a change advantageous for the companies is the reduction in the corporate tax rate from 30% to 28% by the 2014/15 tax year. This Resources Super Profits Tax will also be deductible from the calculation of taxable income. South Africa enacted the Mineral and Petroleum Resources Royalty Acton 1 March 2010. Mining companies would now pay royalties based on a charging formula specifically for refined and unrefined minerals. The minimum royalty charging formula is 0.5% of gross sales regardless of whether the mining company incurs losses. This royalty charging formula is capped at 5% for refined minerals and 7% for unrefined minerals. However, any existing arrangement between mining companies and land owners for special royalties payable is not replaced by the Mineral and Petroleum Resources Royalty Act. A mining company such as Kumba Resources Limited never paid royalties in 2009, but were paying royalties in 2010 at 5.61% of accounting earnings before interest and taxes and 5.51% in 2011. Despite the additional royalties mining companies still invest in South Africa. The main drive for investment is managing risks and investing in projects that yield positive net present values. Typical risks to be managed are taxation laws, political uncertainty and social issues. These risks should be kept under control as the likelihood of mining companies walking away from investments is high when these risks spiral out of control. AFRIKAANS : Regerings dwarsoor die wêreld ondervind wesenlike begrotingstekorte. Die regerings van Suid Afrika en Australië glo dat die belasting op mynbou-maatskappye nie die ‘gewillige koper-gewillige verkoper’ verhouding weerspieël nie. In beginsel beteken dit dat die mynbou-maatskappye in die twee lande nie armlengte-waarde betaal aan regerings vir die ontginning van minerale nie. In Australië het owerhede die Minerale Super Winste Belasting gepromulgeer wat 40% heffings van berekende winste vereis. Mynbou-maatskappye is steeds in die donker oor hoe om hierdie nuwe belasting te hanteer wanneer dit op 1 Julie 2012 in werking tree.Die verlaging van die korporatiewe belastingkoers van 30% na 28% oor ’n tydperk tot en met die 2014/15 belastingjaaris egter ’n verandering wat voordelig is vir die maatskappye. Hierdie Minerale Super Winste Belasting sal ook van belasbare inkomste van mynbou-maatskappye aftrekbaar wees. Suid Afrika het die Minerale en Petroleum Reserwes Tantieme Wet op 1 Maart 2010 gepromulgeer. Mynbou-maatskappye sal in die vervolg tantieme betaal wat gebaseer word op ’n heffingsformule spesifiek ontwerp vir verwerkte en onverwerkte minerale. Die minimum tantieme heffingsformule is 0.5% van bruto verkope ongeag of die mynbou-maatskappy verliese ly. Hierdie tantieme heffingsformule word wel beperk tot 5% vir verwerkte minerale en 7% vir onverwerkte minerale. Enige huidige ooreenkoms met grondeienaars vir die betaling van spesiale tantieme word ongelukkig nie oorskryf deur die Minerale en Petroleum Reserwes Tantieme Wet nie. ’n Mynbou-maatskappy soos Kumba Resources Beperk het geen tantieme in 2009 betaal nie. In 2010 was Kumba Resources Beperk se tantieme 5.61% van rekeningkundige wins voor rente en belasting en in 2011 was dit 5.51%. Ondanks hierdie addisionele tantieme belê mynbou-maatskappye steeds in Suid Afrika. Die hoof-dryfveer vir beleggings is die bestuur van risiko en belegging in projekte wat positiewe netto huidige waardes lewer. Tipiese risiko’s wat bestuur moet word, is belastingwette, politieke onsekerheid en sosiale kwessies. Hierdie risiko’s moet te alle tye onder beheer gehou word omrede mynbou- maatskappye heel waarskynlik van beleggings kan onttrek indien die risiko’s buite beheer raak. Copyright / Dissertation (MCom)--University of Pretoria, 2013. / Taxation / unrestricted

Thesis (M. Sc. (Zoology)) -- University of Limpopo, 2015 / The unprecedented expansion in human population and industry, since the industrial revolution in the late 1700s, has led to increased anthropogenic activities which have indisputably impacted freshwater ecosystems and biological communities therein, including fish. Although this has understandably been the focus, under natural aquatic conditions, no organism is only affected by pollution. Parasites have also been shown in a number of interdisciplinary studies to affect the health of aquatic hosts (amphibians, crustaceans, fish, and mammals). This is illustrated in a number of comprehensive studies the detrimental effects parasites exacerbate when their hosts (fish) are stressed. Therefore, the ability of parasites to interact with anthropogenic stressors, as well as effects they have on the genetic, cellular or tissue level of their host is crucial in conservation and sustaining aquatic biodiversity. As such, the present study examined the combined effects of pollution and metazoan parasites on the health and oxidative stress biomarkers, evaluated for the first time for silver carp, Hypophthalmichthys molitrix (Valenciennes, 1844) and rednose mudfish, Labeo rosae Steindachner, 1894, in one of South Africa’s impacted freshwater ecosystems, Flag Boshielo Dam, Olifants River System, Limpopo Province. Seasonal surveys were conducted from February 2012–January 2013. A total of 111 H. molitrix and 116 L. rosae fish specimens were collected using conventional angling gear, scoop and gill nets with stretched mesh sizes of 30–110 mm. The two selected cyprinid fish species were assessed for oxidative stress biomarkers [Glutathione S-transferase (GST), lipid peroxidation (MDA) and Total Antioxidant Capacity (TAC)] and parasitism of metazoan parasites. Concentrations of biomarkers of oxidative damage and antioxidant defense in the gill and liver tissue were measured to assess how these major organs of the immune system responded to oxidative stress associated with parasitic infections. In addition, water quality analyses were carried out by testing an assay of physico-chemical parameters to establish the level of contamination. Fish health was assessed using the Health Assessment Index (HAI), refined Parasite Index (PI), Inverted Parasite Index (IPI) and Condition Factor (K) protocols. Relative to previous studies at Flag Boshielo Dam, water quality results showed an increase of nutrients, major ions and several metals which may have adverse effects that may comprise fish health; however, this dam remains moderately polluted in a mesotrophic state. The fish health assessment results indicated that H. molitrix was more affected in terms of the necropsy and parasite based assessments (HAI, IPI and K) with mean±SD of 65.68±35.51; 68.29±25; 0.82±0.20, respectively, as compared to 39.14±22.44; 28.79±18.33; 1.17±0.21 for L. rosae during the study. In addition, significantly higher parasitic infections (mean prevalence of infection with any species of parasite = 45.3±0.13) were observed for H. molitrix than L. rosae (12.0±0.05). Furthermore, there was considerable variation in biomarker concentration between highly infected and non-infected fish, for and between each species and tissues with regard to parasite infection, suggesting that the specific functions of each tissue are associated with their susceptibility to oxidative stress, as well as their ability to defend against oxidative damage. These results illustrate that although fish are affected by aquatic contaminants they are to an extent affected by parasites, which may act synergistically on the health of the two fish species. Most importantly, it was suggested that knowledge on the parasites of alien H. molitrix when compared to indigenous L. rosae may give an indication of how adaptive this fish are to new localities as well as expands the information on the rarely studied biology, epizootiology and ecological interactions of these two cyprinid species. Keywords: Health Assessment Index, refined Parasite Index, Inverted Parasite Index, Condition Factor, water quality, lipid peroxidation, Glutathione S-transferase, Total Antioxidant Capacity, Hypophthalmichthys molitrix, Labeo rosae, Flag Boshielo Dam.