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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Monitoring of Lubricant Degradation with RULER and MPC

Maguire, Emma January 2010 (has links)
<p>Traditional oil analysis methods - e.g. acidity and viscosity measurements - have been used to monitor lubricant conditions. These methods can detect when the useful life of a lubricant is over but fall short when trying to gain insight on how long a lubricant in current use could last. This makes it difficult to make proactive decisions and estimate oil drain periods. Lubricants do not start to degrade until the antioxidants, which prevent from oxidation, have depleted to a certain level where they no longer can protect the base oil from degradation. During the degradation process insoluble contaminants form that can lead to sludge and varnish.</p><p>Four engine oils were oxidized using oxygen pressurized vessels and four hydraulic oils were oxidized with turbine oil stability test (TOST). At different stages of oxidation, sample aliquots were withdrawn and analysed. A blend of engine oil and biodiesel was also tested as well as a mixture of hydraulic oil and water. Samples of engine oils were also tested from a rig test running at SCANIA’s facilities in Södertälje, Sweden. The samples were evaluated with Remaining Useful Life Evaluation Routine (RULER) and Membrane Patch Colorimetry (MPC). RULER is a voltammetric method that measures the antioxidant level in a lubricant sample and MPC measure the insoluble contaminants by spectrophotometric analysis. Results from these analyses were compared to conventional methods such as acid number, viscosity, and Fourier Transform Infrared spectroscopy (FTIR).</p><p>Results from the MPC-analyses showed that this method is dependent on the type of the lubricant tested. RULER performed well for all tested lubricants. It was shown that this analyse method can predict when the lubricant is going to start to degrade due to oxidation. Tests showed that the oxidation of the lubricant starts when there are 20-25% of the antioxidants remaining.</p>
2

Monitoring of Lubricant Degradation with RULER and MPC

Maguire, Emma January 2010 (has links)
Traditional oil analysis methods - e.g. acidity and viscosity measurements - have been used to monitor lubricant conditions. These methods can detect when the useful life of a lubricant is over but fall short when trying to gain insight on how long a lubricant in current use could last. This makes it difficult to make proactive decisions and estimate oil drain periods. Lubricants do not start to degrade until the antioxidants, which prevent from oxidation, have depleted to a certain level where they no longer can protect the base oil from degradation. During the degradation process insoluble contaminants form that can lead to sludge and varnish. Four engine oils were oxidized using oxygen pressurized vessels and four hydraulic oils were oxidized with turbine oil stability test (TOST). At different stages of oxidation, sample aliquots were withdrawn and analysed. A blend of engine oil and biodiesel was also tested as well as a mixture of hydraulic oil and water. Samples of engine oils were also tested from a rig test running at SCANIA’s facilities in Södertälje, Sweden. The samples were evaluated with Remaining Useful Life Evaluation Routine (RULER) and Membrane Patch Colorimetry (MPC). RULER is a voltammetric method that measures the antioxidant level in a lubricant sample and MPC measure the insoluble contaminants by spectrophotometric analysis. Results from these analyses were compared to conventional methods such as acid number, viscosity, and Fourier Transform Infrared spectroscopy (FTIR). Results from the MPC-analyses showed that this method is dependent on the type of the lubricant tested. RULER performed well for all tested lubricants. It was shown that this analyse method can predict when the lubricant is going to start to degrade due to oxidation. Tests showed that the oxidation of the lubricant starts when there are 20-25% of the antioxidants remaining.
3

Perceptual Ruler for Quantifying Speech Intelligibility in Cocktail Party Scenarios

Brangers, Kirstin M 01 January 2013 (has links)
Systems designed to enhance intelligibility of speech in noise are difficult to evaluate quantitatively because intelligibility is subjective and often requires feedback from large populations for consistent evaluations. Attempts to quantify the evaluation have included related measures such as the Speech Intelligibility Index. These require separating speech and noise signals, which precludes its use on experimental recordings. This thesis develops a procedure using an Intelligibility Ruler (IR) for efficiently quantifying intelligibility. A calibrated Mean Opinion Score (MOS) method is also implemented in order to compare repeatability over a population of 24 subjective listeners. Results showed that subjects using the IR consistently estimated SII values of the test samples with an average standard deviation of 0.0867 between subjects on a scale from zero to one and R2=0.9421. After a calibration procedure from a subset of subjects, the MOS method yielded similar results with an average standard deviation of 0.07620 and R2=0.9181.While results suggest good repeatability of the IR method over a broad range of subjects, the calibrated MOS method is capable of producing results more closely related to actual SII values and is a simpler procedure for human subjects.
4

Starověké základy utopiky a filosofický utopismus ve vybraných spisech / Ancient basics of utopia and philosophical utopism in selected writings

Dolák, Lubomír January 2019 (has links)
Analysis and reflection of selected utopian writings with the aim of presenting utopia as a hope for society about the possibility of the existence of better worlds, as well as a valuable historical source from the times when their authors lives. Introducing utopia as a fictious, artificial place with ideal social structure, attributed to its their authors, and focusing, with use the probe of personal choice, especially regarding the social order, property and religion in these "ideal" states. Submitting a comprehensive and well-arranged elaboration of the whole topic from its general characteristics, through the analysis of selected writings to the final reflection. Brief characteristics of the work content: "Fantastic voyage of the barque of emotions and reason under the rudder of ancient philosophers on the vast oceans criticizing the social conditions inside the soul of the ideal states."
5

A função logaritmo e a régua de cálculo / The logarithm function and the slide rule

Pippa, Tania Cristina Maggioni 17 March 2014 (has links)
No início do século XVII, o escocês John Napier revolucionou os métodos de cálculo da época com a invenção dos logaritmos. O logaritmo de Napier não era exatamente o que usamos hoje. Naquela época, o trabalho de multiplicação, divisão, cálculo de potências e extração de raízes eram trabalhosos e feitos a partir de senos. Surgiram as primeiras tábuas de logaritmos, inventadas independentemente por John Napier (1550-1617) e Jost Bürgi (1552-1632). Pouco depois, Henry Briggs (1561-1631) aperfeiçoou essas tábuas, apresentando os logaritmos decimais. A contribuição fundamental dos logaritmos é a de facilitar os cálculos através da transformação de operações de multiplicação em adição e de operações de divisão em subtração. Essas transformações foram de grande importância nos cálculos trabalhosos que estavam envolvidos em Astronomia e Navegação. Em 1632, um matemático inglês chamado William Oughtred inventou a régua de cálculo, com base na \"Tábua de Napier\". Esse foi um grande passo em direção à calculadora e à construção dos computadores. Nesse trabalho propomos a utilização da régua de cálculo no ensino das propriedades dos logaritmos. Para tanto, foram estudados tópicos como a história dos logaritmos, a função logaritmo, a caracterização das funções logarítmicas, a associação de logaritmos a progressões aritméticas e geométricas e o uso de uma régua de cálculo / In the early seventeenth century, the Scotsman John Napier revolutionized the calculation methods of that time with the invention of logarithms. The Napier logarithm was not exactly the same as we use now. At that time, the multiplication, division, exponents calculation and extracting roots were demanded extensive labor. John Napier (1550-1617) and Jost Bürgi (1552-1632) invented independently the first logarithm tables. Shortly after, Henry Briggs (1561-1631) improved these boards, presenting the decimal logarithms. The main contribution of logarithms is to make calculations easier by transforming multiplication operations into addition ones and division operations into subtraction ones. These changes have been of great importance in laborious calculations that involved Astronomy and Navigation. In 1632, an English mathematician called William Oughtred invented the slide ruler, based on the \"Napier board\". This was a big step towards the invention of the calculator and the computer. In this work we propose the use of the slide ruler in teaching the properties of logarithms. Thus, topics such as the history of logarithms, the logarithm function, the characterization of logarithmic functions, the association of the logarithms with arithmetical and geometrical progressions, and the use of a slide ruler were studied
6

A função logaritmo e a régua de cálculo / The logarithm function and the slide rule

Tania Cristina Maggioni Pippa 17 March 2014 (has links)
No início do século XVII, o escocês John Napier revolucionou os métodos de cálculo da época com a invenção dos logaritmos. O logaritmo de Napier não era exatamente o que usamos hoje. Naquela época, o trabalho de multiplicação, divisão, cálculo de potências e extração de raízes eram trabalhosos e feitos a partir de senos. Surgiram as primeiras tábuas de logaritmos, inventadas independentemente por John Napier (1550-1617) e Jost Bürgi (1552-1632). Pouco depois, Henry Briggs (1561-1631) aperfeiçoou essas tábuas, apresentando os logaritmos decimais. A contribuição fundamental dos logaritmos é a de facilitar os cálculos através da transformação de operações de multiplicação em adição e de operações de divisão em subtração. Essas transformações foram de grande importância nos cálculos trabalhosos que estavam envolvidos em Astronomia e Navegação. Em 1632, um matemático inglês chamado William Oughtred inventou a régua de cálculo, com base na \"Tábua de Napier\". Esse foi um grande passo em direção à calculadora e à construção dos computadores. Nesse trabalho propomos a utilização da régua de cálculo no ensino das propriedades dos logaritmos. Para tanto, foram estudados tópicos como a história dos logaritmos, a função logaritmo, a caracterização das funções logarítmicas, a associação de logaritmos a progressões aritméticas e geométricas e o uso de uma régua de cálculo / In the early seventeenth century, the Scotsman John Napier revolutionized the calculation methods of that time with the invention of logarithms. The Napier logarithm was not exactly the same as we use now. At that time, the multiplication, division, exponents calculation and extracting roots were demanded extensive labor. John Napier (1550-1617) and Jost Bürgi (1552-1632) invented independently the first logarithm tables. Shortly after, Henry Briggs (1561-1631) improved these boards, presenting the decimal logarithms. The main contribution of logarithms is to make calculations easier by transforming multiplication operations into addition ones and division operations into subtraction ones. These changes have been of great importance in laborious calculations that involved Astronomy and Navigation. In 1632, an English mathematician called William Oughtred invented the slide ruler, based on the \"Napier board\". This was a big step towards the invention of the calculator and the computer. In this work we propose the use of the slide ruler in teaching the properties of logarithms. Thus, topics such as the history of logarithms, the logarithm function, the characterization of logarithmic functions, the association of the logarithms with arithmetical and geometrical progressions, and the use of a slide ruler were studied
7

Teste tuberculínico: comparação de dois instrumentos de leitura / Tuberculin skin test: comparison of two reading instruments [Thesis]. São Paulo: School of Public Health of USP, 2012.

França, Flavia Aparecida de Moraes 08 May 2012 (has links)
Introdução- A busca ativa de indivíduos infectados pelo Mycobacterium tuberculosis, com o auxílio do teste tuberculínico, principalmente em populações de detentos, moradores de rua, infectados pelo vírus do HIV entre outras, tem como objetivo prevenir a evolução da infecção para a doença tuberculose e auxiliar o conhecimento de novos casos da doença. O teste tuberculínico é uma importante ferramenta, para identificar os indivíduos reatores (infectados) e não reatores (não infectados). Ele pode ser aplicado a partir de várias técnicas, mas a que permite a padronização e a comparação dos resultados é a técnica intradérmica de Mantoux, a mais usada atualmente. No Brasil, a leitura do resultado do teste tuberculínico é realizada, por recomendação do Ministério de Saúde, com régua milimetrada. Para seu uso é necessário um treinamento rigoroso, o que tem contribuído para a diminuição de leitores do teste tuberculínico na rotina dos serviços de saúde. Como alternativa temos outro instrumento, paquímetro, ainda não padronizado no Brasil. Outros países o utilizam nas rotinas dos serviços de saúde para busca de indivíduos reatores ou não ao teste tuberculínico, ele não cabe para aferição ou inquéritos epidemiológicos. Objetivo- Comparar os instrumentos de leitura dos resultados do teste tuberculínico obtidos através da leitura padronizada, feita por régua milimetrada, e a leitura, não padronizada, feita por paquímetro. Métodos- Estudo descritivo realizado numa população prisional de uma Penitenciária e de um Centro de Detenção Provisória, da cidade de Guarulhos, Grande São Paulo, entre os meses de março a junho de 2008. Foi realizada a leitura do teste tuberculínico de forma dupla cega, por dois leitores, com instrumentos diferentes, paquímetro e régua milimetrada. Resultados- Foram administrados testes tuberculínicos em 1954 indivíduos; destes 111 foram excluídos por não terem comparecido à leitura do teste, resultando em uma amostra de 1843 indivíduos divididos em 1059 (57,5 por cento ) na Penitenciária e 784 (42,5 por cento ) no Centro de Detenção Provisória. Os resultados comparativos entre os dois instrumentos, quando avaliados os reatores com os não reatores, foram altos e equivalentes, pois a sensibilidade (93 por cento ) e a especificidade (97 por cento ) foram praticamente as mesmas. A média da concordância foi alta entre os dois instrumentos (95,5 por cento ) e a discordância foi baixa (4,5 por cento ). O Ministério da Saúde preconiza uma concordância acima de 80 por cento para aferição de novos leitores. Conclusões- Com este estudo observamos que o paquímetro pode ser considerado equivalente à régua milimetrada e poderá ser uma alternativa à régua para a leitura do teste tuberculínico no Brasil, principalmente para a busca de casos de tuberculose latente na rotina dos serviços de saúde, por ser um bom instrumento de separação dos indivíduos e não é suficiente para aferir um novo leitor. Entretanto, a régua deverá ser mantida, especialmente para inquéritos epidemiológicos / Introduction- The active search of individuals infected with Mycobacterium tuberculosis aims to prevent the development of infection to the disease tuberculosis and ancillary knowledge of new cases of the disease. The tuberculin test is an important tool to identify individuals (infected) and non-reactors reactors (noninfected). It can be applied from various techniques. Nowadays Mantoux intradermal technique is the most widely used and allows the standardization and comparability of results. In Brazil, the reading of the tuberculin test result is performed with a ruler, by recommendation of the Ministry of health. For its use is required a rigorous training, which has contributed to the decline of tuberculin test readers in routine health services. Alternatively, caliper rule is a technique that can be used, but it is not standardized in Brazil. Objective- Compare the reading instruments of tuberculin skin test results obtained through the standardized reading, made by a millimeter ruler, and reading, not standardized, made with a caliper rule. Method- It was a descriptive study in a prison population of a Penitentiary and a Provisional Detention Centre in the city of Guarulhos, São Paulo, between the months of March to June 2008. Tuberculin test reading was done in a double blind, tuberculin test by two readers, with different instruments, ruler and caliper rule. Results- Tuberculin skin tests were administered to 1,954 individuals; of these 111 was excluded for failing to appear for the reading test, resulting in a sample of 1,843 individuals divided in 1,059 (57.5 per cent ) in Penitentiary and 784 (42.5 per cent ) in the Provisional Detention Center. The comparative results between the two instruments were high and equivalent (sensitivity=93 per cent and specificity=97 per cent ). The average correlation was high among the two instruments (95.5 per cent ) and the disagreement was low (4.5 per cent ). The Ministry of Health recommends a concordance above 80 per cent for benchmarking new readers. Conclusions- We observed that the caliper rule can be considered equivalent to the rule and may be an alternative for reading the tuberculin test in Brazil, especially to search for latent TB cases. However, the rule should be maintained, especially toepidemiological investigations
8

Xenofonte e a paideia do governante / Xenophon and the rulers paideia

Lima, Alessandra Carbonero 25 September 2012 (has links)
Nossa investigação explora a possibilidade de o tema da paideia ser um eixo comum em torno do qual se articulam os textos de Xenofonte de Atenas, autor do século IV a.C. Julgamos que essa perspectiva se justifica em razão da importância que esse autor atribui à construção de retratos de homens paradigmáticos. Ilustramos esse procedimento com a análise do retrato que o próprio Xenofonte constrói para si, na Anabase. É sobretudo a partir da análise desses retratos que podemos ver, em Xenofonte, a discussão do tema da paideia. Os estudos que aqui empreendemos concentram-se no tema da paideia do governante. Nesse horizonte, oferecemos uma possível leitura para o retrato daquele que o autor considera a contrafacção do governante ideal, o tirano Hierão, de diálogo homônimo. Por fim, ocupamo-nos dos elementos que compõem o retrato xenofôntico do governante paradigmático, Ciro, o velho, da Ciropédia. / Our research explores the possibility of the theme of paideia as a common axis around which are articulated the texts of Xenophon of Athens, author of the fourth century BC. We believe that this perspective is justified because of the importance this author gives to the construction of portraits of paradigmatic men. We illustrate this procedure with the analysis of the portrait which Xenophon builds for himself in the Anabasis. It is mainly based on the analysis of such portraits that we can see, in Xenophon, the discussion on the theme of paideia. The studies undertaken here focus on the theme of the ruler\'s paideia. In this horizon, we offer a possible reading for the portrait of the man the author considers the counterfeiting of the ideal ruler, the tyrant Hiero, in the corresponding dialogue. Finally we deal with the elements that make up the portrait of Xenophons paradigmatic ruler, Cyrus the Great, of the Cyropaedia.
9

Jogos lógicos no Ensino Fundamental

Rosa, Leandro Viana da January 2016 (has links)
Esta pesquisa se dedicou à introdução dos jogos lógicos na sala de aula, em específico, ela busca a investigação das dificuldades encontradas pelos alunos com os diferentes estilos de jogos apresentados e quais são os raciocínios lógicos utilizados para a resolução dos problemas propostos. Buscamos os benefícios que estes jogos podem trazer para o ensino e a aprendizagem na sala de aula. Aliado a isso também trabalhamos a parte geométrica dos tabuleiros, e com isso os alunos utilizaram como ferramentas a régua e o compasso para a construção dos tabuleiros apresentados.. Para tanto, a metodologia de pesquisa escolhida foi o Estudo de Caso, de acordo com Fiorentini e Lorenzato (2006), Ventura (2007) e Gil (2002). O referencial teórico é baseado nos trabalhos de Macedo (2007), Grando (2011), Skovsmose (2000), Huizinga (2000), Kishimoto (2006), Zuin (2001), bem como os PCNs e outros artigos/livros relacionados aos jogos lógicos e as construções geométricas com a régua e o compasso. As atividades foram desenvolvidas com uma turma do 9º ano do Ensino Fundamental de em uma Escola Municipal de Porto Alegre, no ano de 2015. Em especial sugerimos que é possível a inserção desses materiais a fim de serem usados como ferramentas de auxílio no ensino aprendizagem de matemática contribuindo positivamente para a formação dos alunos. Os registros coletados no estudo de caso possibilitaram a validação da proposta. / The present research has focused on the introduction of the logical games in the class. It aims to pin point difficulties presented by the students on the different styles of games proposed and a logical ratiocination is required to solve the tasks proposed. The benefits of the games along with the teaching and learning in the classroom was the goal. Additionally, the geometric segment of board games have been investigated and students used tools as ruler and compass to the construction of the boards presented. Therefore, the chosen researching methodology was the Case Study, according to Fiorentini e Lorenzato (2006), Ventura (2007) e Gil (2002). The theoretical referential is based on Works from Macedo (2007), Grando (2011), Skovsmose (2000), Huizinga (2000), Kishimoto (2006), Zuin (2001), along with the PCNs and others articles/books related to logical games and geometric constructions with a ruler and a compass. The activities were performed by a 9th grade group of the Elementary School in a Municipal School in Porto Alegre, in 2015. We showed in particular that is possible the insertion of these materials in order to be used as a sustenance tool on Mathematics Learning contributing positively to students formation. The data collected in the case study enabled the authentication of the proposal.
10

Construções geométricas e os problemas de apolônio / Geometric construction, ruler, compass, apollonius' problem

Vieira, Mariana Araújo 22 March 2013 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2014-09-23T12:11:15Z No. of bitstreams: 2 Vieira, Mariana Araujo.pdf: 2336552 bytes, checksum: a3cdecc71ec9fe00f17a840ededdcce2 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2014-09-23T15:10:25Z (GMT) No. of bitstreams: 2 Vieira, Mariana Araujo.pdf: 2336552 bytes, checksum: a3cdecc71ec9fe00f17a840ededdcce2 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2014-09-23T15:10:25Z (GMT). No. of bitstreams: 2 Vieira, Mariana Araujo.pdf: 2336552 bytes, checksum: a3cdecc71ec9fe00f17a840ededdcce2 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2013-03-22 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This paper aims to present the main problems of Apollonius.... / Este trabalho tem como objetivo principal apresentar os dez problemas de Apôlonio....

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