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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

Opting in to an Opt-out System: Presumed Consent as a Valid Policy Choice for Ontario's Cadaveric Organ Shortage

Dolling, Jennifer Margaret 14 January 2010 (has links)
Established within the context of a severe shortage of organs and tissues for transplantation, this thesis explores whether presumed consent for cadaveric organ donation is a legitimate policy choice for Ontario. The medical, legal and social reasons underlying organ scarcity and increased demand for transplantation are examined, and the shortcomings of Ontario’s current express consent system are analyzed. The various criticisms of presumed consent are also explored, including concerns with respect to its effectiveness, level of public support and implications for personal autonomy. Although the Citizens Panel on Increasing Organ Donations recommended against enacting presumed consent legislation, it is argued that the Panel was too dismissive of this concept given a perceived lack of public support. It is concluded that presumed consent can meet the concerns of critics, and that as part of a broader strategy could significantly increase the number of cadaveric organ and tissue donors in the province.
2

Opting in to an Opt-out System: Presumed Consent as a Valid Policy Choice for Ontario's Cadaveric Organ Shortage

Dolling, Jennifer Margaret 14 January 2010 (has links)
Established within the context of a severe shortage of organs and tissues for transplantation, this thesis explores whether presumed consent for cadaveric organ donation is a legitimate policy choice for Ontario. The medical, legal and social reasons underlying organ scarcity and increased demand for transplantation are examined, and the shortcomings of Ontario’s current express consent system are analyzed. The various criticisms of presumed consent are also explored, including concerns with respect to its effectiveness, level of public support and implications for personal autonomy. Although the Citizens Panel on Increasing Organ Donations recommended against enacting presumed consent legislation, it is argued that the Panel was too dismissive of this concept given a perceived lack of public support. It is concluded that presumed consent can meet the concerns of critics, and that as part of a broader strategy could significantly increase the number of cadaveric organ and tissue donors in the province.
3

The Effect of Presumed Media Influence on College Athletes

Anderson, Justin E. 10 August 2012 (has links)
In this article, I examine the notion that perceptions of media have a perceived effect on performance and morale on both the athlete and the team. I test this idea on a sample of college athletes at Nicholls State University (N=94), at the end of the 2011-2012 school year. Findings show that the presumed media influence is displayed in the context of athletics and that there are some indirect effects from one's perceptions of how their teammates were portrayed in the media. Research found that positive media had a perceived effect on the team but not on ones' self. Findings also showed that positive and negative media can be a predictor of overall team performance. Nothing was found to support the idea that positive or negative media had an impact on personal performance or morale. Nothing was found that gave credence to the fact that perception of media whether positive or negative has an impact on personal or team morale.
4

Evaluating expert advice in forecasting: users' reactions to presumed vs. experienced credibility

Onkal, Dilek, Gonul, M.S., Goodwin, P., Thomson, M., Esra, O. 2016 April 1925 (has links)
Yes / In expert knowledge elicitation (EKE) for forecasting, the perceived credibility of an expert is likely to affect the weighting attached to their advice. Four experiments have investigated the extent to which the implicit weighting depends on the advisor’s experienced (reflecting the accuracy of their past forecasts), or presumed (based on their status) credibility. Compared to a control group, advice from a source with a high experienced credibility received a greater weighting, but having a low level of experienced credibility did not reduce the weighting. In contrast, a high presumed credibility did not increase the weighting relative to a control group, while a low presumed credibility decreased it. When there were opportunities for the two types of credibility to interact, a high experienced credibility tended to eclipse the presumed credibility if the advisees were non-experts. However, when the advisees were professionals, both the presumed and experienced credibility of the advisor were influential in determining the weight attached to the advice.
5

Abordagem da concessão de crédito presumido de ICMS na Paraíba e a questão do desenvolvimento

Silva, Saulo Medeiros da Costa 29 April 2014 (has links)
Submitted by Jean Medeiros (jeanletras@uepb.edu.br) on 2016-03-10T18:08:33Z No. of bitstreams: 1 PDF - Saulo Medeiros da Costa Silva.pdf: 6523230 bytes, checksum: 8e5bf7ca87269a0cdaca1b4b203e0223 (MD5) / Approved for entry into archive by Secta BC (secta.csu.bc@uepb.edu.br) on 2016-07-21T20:49:03Z (GMT) No. of bitstreams: 1 PDF - Saulo Medeiros da Costa Silva.pdf: 6523230 bytes, checksum: 8e5bf7ca87269a0cdaca1b4b203e0223 (MD5) / Approved for entry into archive by Secta BC (secta.csu.bc@uepb.edu.br) on 2016-07-21T20:49:15Z (GMT) No. of bitstreams: 1 PDF - Saulo Medeiros da Costa Silva.pdf: 6523230 bytes, checksum: 8e5bf7ca87269a0cdaca1b4b203e0223 (MD5) / Made available in DSpace on 2016-07-21T20:49:15Z (GMT). No. of bitstreams: 1 PDF - Saulo Medeiros da Costa Silva.pdf: 6523230 bytes, checksum: 8e5bf7ca87269a0cdaca1b4b203e0223 (MD5) Previous issue date: 2014-04-29 / The present investigation examined the concessive standards ICMS tax subsidies, specifically the presumed credit, in Paraíba state, and the impact of such tax benefits and its binding or not, to regional development in the period 2001-2013. Goal general was to analyze the relationships between the concessive standards presumed credits of ICMS , Paraiba , and regional development. The specific objectives are : 1 ) discuss the right to development ; 2 ) describe federalism , in particular fiscal , Brazil ; 3 ) treating the main source of financing for Brazilian States, the ICMS tax; 4 ) analyze the period 2001-2013 , the economic evolution of the waiver of revenue typified presumed credit in the State of Paraíba, comparing it with the Paraiba socioeconomic development in the same period . We used the qualitative research model - functionalist, merely descriptive of reality. This research , then, fits the genre of theoretical research, despite making use of data not only bibliographic and documentary , but also quantitative. We found that the policy of tax breaks by granting deemed ICMS credit grew astronomically form without generating development to the state, on the contrary, what is observed is a slow economic growth, income concentration, low wages, and especially dark, illegality, incoherence, lack of planning and criteria for granting the ICMS tax benefits, with a clear violation of the constitutional principles of legality, equality, publicity, legal certainty and federalism. / A presente investigação analisou as normas concessivas de subsídios fiscais de ICMS, especificamente o crédito presumido no Estado da Paraíba e a repercussão de tais benefícios fiscais e a sua vinculação, ou não, com o desenvolvimento regional, no período compreendido entre os anos 2001 a 2013. O objetivo geral foi analisar as relações entre as normas concessivas de créditos presumidos do ICMS, na Paraíba, e o desenvolvimento regional. Os objetivos específicos foram: 1) discorrer sobre o direito ao desenvolvimento; 2) descrever o federalismo, em especial o fiscal brasileiro; 3) tratar da principal fonte de financiamento dos Estados-membros brasileiros, o imposto ICMS; 4) analisar, no período de 2001 a 2013, evolução econômica da renúncia de receita tipificada de crédito presumido na Paraíba; 5) confrontar a evolução das renúncias de receita de crédito presumido com o desenvolvimento sócioeconômico paraíbano nesse período; 6) Verificar a observância dos princípios constitucionais tributários na concessão do crédito presumido. Utilizamos o modelo de investigação qualitativofuncionalista, meramente descritivo da realidade. A presente pesquisa, então, enquadrase no gênero de pesquisa teórica, apesar de fazer uso de dados não só bibliográficos e documentais, mas também quantitativos. Verificamos que a política de renúncia fiscal mediante a concessão de crédito presumido de ICMS cresceu de forma astronômica sem gerar desenvolvimento ao Estado, pelo contrário, o que se observa é um crescimento econômico lento, com concentração de renda, baixos salários, taxa de pobreza ainda elevada, e, principalmente, obscuridade, incoerência, inexistência de planejamento e de critérios para outorga os benefícios fiscais de ICMS, com nítida violação aos princípios constitucionais da legalidade, isonomia, publicidade, segurança jurídica e ao federalismo.
6

Diálogo e ética: marcas da heterogeneidade constitutiva no ensaio para uma filosofia do ato responsável de Bakhtin

Silva, Helcia Macedo de Carvalho Diniz e 24 February 2015 (has links)
Submitted by Maria Suzana Diniz (msuzanad@hotmail.com) on 2015-11-23T13:12:31Z No. of bitstreams: 1 arquivototal.pdf: 1170942 bytes, checksum: b6572bc762a0d2c24c5e7ff182b558fb (MD5) / Made available in DSpace on 2015-11-23T13:12:31Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 1170942 bytes, checksum: b6572bc762a0d2c24c5e7ff182b558fb (MD5) Previous issue date: 2015-02-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This research is developed from two categories dear to Bakhtinian thought, dialogue and ethics, and seeks to delimit some philosophical assumptions underlying the Bakhtinian theory of language. We therefore provide an analytical reading of the essay written approximately between the years 1920 to 1924, whose text, considered a fragment, has the following title: For a Philosophy of the Responsible Act (hereafter referred to in this paper as PFAR) by Mikhail Mikhailovich Bakhtin (1895-1975). The corpus chosen, whose hermetic nature is unfinished, imposes difficulties and motivates this work, which covers two moments: reading as a documental research and the interpretative analysis of the passages in the light of the methodological theory, which makes it possible to find philosophical assumptions in the Bakhtinian Theory of Language. In this way, one can clarify the constitutive heterogeneity by Authier-Revuz (1982, 1990, 1998, 2004, and 2007) and of the voices in the Bakhtinian text, given that not always do these appear in an explicit form when the categories, ethics and dialogism, are developed. From this author we work, especially, with the concepts of shown and constituted heterogeneity, in an approach that requires of the author a positioning and a justification for the reasons that result in his choices. In this way, this task is beyond the identification of discursive heterogeneity. The intention, here, is to characterize Kierkegaard ([1844] 2010) and Buber ([1923] 2001) as the presumed philosophers in Bakhtin ([1920-24] 2010). These theories are important: Ponzio (2010), Faraco (2010a), Tezza (2003) e Sobral (2005a, 2005b, 2009, 2010). With this in mind, specific procedures are necessary, which provide the systematic analysis and the interpretation of the data. In this way, the methodology has an exploratory character and an interpretative stamp. It remains to be seen if the Bakhinian conception of ethics and of dialogism presents discursive heterogeneity with the thoughts of Kierkegaard ([1844] 2010) and Buber ([1923] 2001) are consist of the trademarks of constitutive heterogeneity of language, respectively. / O objetivo geral desta pesquisa é analisar as marcas de heterogeneidade constitutiva por meio de duas categorias da Filosofia Bakhtiniana da Linguagem, a saber, diálogo e ética. Estas se sobressaíram do ensaio Para uma filosofia do ato responsável. Escrito do jovem Mikhail Mikhailovich Bakhtin (1895-1975) que constitui o corpus desta tese. Embora tenha sido publicado pela primeira vez em russo, no ano 1986, com o título K filosofii postupok, foi escrito por volta de 1920 e 1924. Constituem os objetivos específicos: a) apresentar o contexto histórico e social referentes ao corpus, b) Traçar o caminho metodológico da análise, c) expor os conceitos de ética e diálogo, d) destacar as marcas de heterogeneidade constitutiva, e) discutir o diálogo heterogeneamente constitutivo de Bakhtin ([1920-1924] 2010) com os filósofos Kierkegaard ([1844] 2010), no tocante à ética e Buber ([1923] 2001), no que diz respeito ao diálogo. Principalmente Bakhtin ([1920-1924] 2010) e os estudiosos Ponzio (2010), Faraco (2010a), Tezza (2003) e Sobral (2005a, 2005b, 2009, 2010) são os teóricos que respaldam esta pesquisa. O aporte teórico-metodológico segue a abordagem da Teoria da Enunciação da linguista francesa Authier-Revuz (1982, 1990, 1998, 2004, 2007), eixo teórico-metodológico que possibilita realizar este empreendimento. Em consonância com esta proposta, pautamo-nos no conceito da heterogeneidade constitutiva, porque acreditamos que este trabalho vai mais além do ato investigar os pressupostos filosóficos na Filosofia Bakhtiniana da Linguagem. Para tanto, esta é uma investigação, de caráter exploratório e de natureza qualitativa cujos procedimentos metodológicos abrangem dois momentos: pesquisa documental e análise interpretativista. Desse modo, é imperativo perguntar: quem são os filósofos que Bakhtin ([1920-1924] 2010) convidou para dialogar sobre a ética e o diálogo, enquanto assuntos específicos para a sua Filosofia da Linguagem? Partimos, portanto, da seguinte hipótese: as marcas de heterogeneidade constitutiva no corpus analisado encontram-se nas categorias, ética e diálogo, a partir de dois pensadores, a saber, o dinamarquês Søren Aabye Kierkegaard (1813-1855) e o austríaco Martin Buber (1878-1965), respectivamente.
7

Lucro real x lucro presumido em empresas de produtos alimentícios: o caso da Distribuidora Farias Ltda

Castro, Edimilton Araújo de 25 November 2011 (has links)
Submitted by Lúcia Brandão (lucia.elaine@live.com) on 2015-08-11T20:14:07Z No. of bitstreams: 1 Dissertação - Edimilton Araújo de Castro.pdf: 705104 bytes, checksum: bf1fc25bd2967c27649c810c30c33ef8 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2015-08-12T15:42:37Z (GMT) No. of bitstreams: 1 Dissertação - Edimilton Araújo de Castro.pdf: 705104 bytes, checksum: bf1fc25bd2967c27649c810c30c33ef8 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2015-08-12T15:52:18Z (GMT) No. of bitstreams: 1 Dissertação - Edimilton Araújo de Castro.pdf: 705104 bytes, checksum: bf1fc25bd2967c27649c810c30c33ef8 (MD5) / Made available in DSpace on 2015-08-12T15:52:18Z (GMT). No. of bitstreams: 1 Dissertação - Edimilton Araújo de Castro.pdf: 705104 bytes, checksum: bf1fc25bd2967c27649c810c30c33ef8 (MD5) Previous issue date: 2011-11-25 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Inaccordance with the themespresented, the survey was developedas thegoalwas to showabetterstrategicoption to taxfor the companyDistribuidoraLtdaFarias. Consideringthe possibilitiesof optionsestimatedtaxbetweentaxable incomeand theAssumed Income. Tomeet the goalwas adoptedbythe case studymethodwhich is based ondescriptiveexploratory researchin orderto interpret the resultsto understand thehistorical processes andconceptsabout the topicbased onthe perceptionof a phenomenonin a certaincontext.Theresearch was conducted throughthe collection of informationondirect and indirectdocumentationprovided by the companyfor the period from2009to 2010, which are considered of paramountimportance tothis work. Data collectionwas performed atFariascompany DistribuidoraLtda., Located in the city ofManaus/ AM, concentrating research intax paymentsthrough theAssumed Incomewhiledoingasimulation for thetaxable incomein order toobserve thecomparison betweenboth.Through this comparisonwe determine theadvantages anddisadvantagesin relation toincometaxationbyPresumedor Real. We emphasizethat the studylooked mainlytaxthe branchof business activityand percentageof costs,expenses andprofit marginspredictable.After reviewingthe documents of thecompanystudied waspossible to prepareademonstrationcomparing thetaxes paidin thequarter to quarteras muchasRealModeNetIncomeAssumedexercisesof2009and 2010, which evidencedthatthe companystudiedthe maintenance of thepresumed profithadeconomic advantages. / De acordo com a temática apresentada, a pesquisa foi desenvolvida conforme o objetivo que consistiu em mostrar uma melhor opção de tributação para a empresa Distribuidora Farias Ltda., considerando as possibilidades de opções tributárias estimada entre o Lucro Real e o Lucro Presumido. Para alcançar o objetivo proposto adotou-se por método o estudo de caso que se fundamenta na pesquisa exploratória descritiva, visando interpretar os resultados para compreender os processos históricos e conceituais sobre o tema abordado tendo como base a percepção de um fenômeno em certo contexto. A pesquisa foi realizada através do levantamento de informações nas documentações direta e indireta disponibilizadas pela empresa referente ao período de 2009 e 2010, dados considerados de suma importância para a realização deste trabalho. A coleta dos dados foi realizada na empresa Distribuidora Farias Ltda., localizada na cidade de Manaus/AM, concentrando a pesquisa nos pagamentos dos impostos através do Lucro Presumido fazendo ao mesmo tempo uma simulação para o Lucro Real com o intuito de observar a comparação entre ambos. Com esta comparação determinamos as vantagens e desvantagens em relação às tributações pelo Lucro Presumido ou Real. Ressaltamos que, o estudo tributário levou em consideração principalmente o ramo de atividade da empresa e percentuais de custos, despesas e margens de lucros previsíveis. Após analisar os documentos da empresa estudada foi possível elaborar uma demostração comparativa entre os tributos pagos trimestre a trimestre tanto na modalidade do Lucro Real como do Lucro Presumido dos exercicios 2009 e 2010, no qual evidenciamos que para a empresa em estudo a manutenção do lucro presumido apresentou vantagens econômicas.
8

An Analysis of the Doctrine of presumed consent and the principles of required response and required request in organ procurement

Fourie, Etienne Jean 07 February 2007 (has links)
The transplantation process establishes a three-phase structure namely, procurement, preservation and allocation of human organs and tissue. These three phases are co-dependent upon the successful completion of each individual phase within that structure. This dissertation focus specifically on the first phase of the transplantation process and endeavours to analyse the doctrine of presumed consent as applied in the procurement of human organs and tissue. Thereafter, the focus point is directed upon organ procurement incentives such as the principle of required response and required request that ensure the effective application of these systems should be interconnected with organ procurement systems. Finally, a capita selecta of issues pertaining to the final two stages of the transplantation process are investigated and proposed problem areas are reflected upon. The doctrine of presumed consent as an organ procurement system proposes that individuals who fail to raise an objection in respect of organ donation during their lifetime, will upon death be presumed that they provided consent to the removal of their organs. This system operates in absolute contrast to the doctrine of informed consent as applied in South African law, establishes that an ommissio to act would constitute an implicit statement of informed consent. The application of the doctrine of presumed consent can be classified as either a hard application or a soft application. A strong application declares that upon death a who failed to raise an objection to organ donation will be considered to given consent to organ procurement and any interference by the next-of-kin are disregarded. The weak application functions in a similar way than the hard application, with the exception that the next-of-kin has the right to override the decision. This dissertation analyses whether the element of consent in the doctrine of presumed consent can be classified as a justification ground as the doctrine of informed consent of whether it infringes upon section 12(2)(b) of the South African Constitution (Act 108 of 1996). To establish the true nature of the doctrine of consent, specific reference is made the duty of disclosure that rested upon the health practitioner to inform patients about information about a proposed treatment. Arguments are raised that the nature, scope and accessibility of information about issues relating to organ donation will determine if informed consent is present in the doctrine of presumed consent. The introduction of the doctrine of presumed consent as organ procurement system could provide South Africa with an essential framework to increase organ procurement and awareness about organ donation provided that sufficient information can be accessed in an easy and effective manner. The following concepts are analysed in the dissertation: The doctrine of presumed consent The principle of required response The principle of required request The doctrine of informed consent Organ procurement incentives Routine salvaging Organ procurement systems Organ preservation and safeguarding Organ allocation systems Human Tissue and organs The moment of death / Dissertation (Magister Legum (Public Law))--University of Pretoria, 2007. / Public Law / unrestricted
9

Conditional Moment Closure Methods for Turbulent Combustion Modelling

El Sayed, Ahmad 18 March 2013 (has links)
This thesis describes the application of the first-order Conditional Moment Closure (CMC) to the autoignition of high-pressure fuel jets, and to piloted and lifted turbulent jet flames using classical and advanced CMC submodels. A Doubly-Conditional Moment Closure (DCMC) formulation is further proposed. In the first study, CMC is applied to investigate the impact of C₂H₆, H₂ and N₂ additives on the autoignition of high-pressure CH₄ jets injected into lower pressure heated air. A wide range of pre-combustion air temperatures is considered and detailed chemical kinetics are employed. It is demonstrated that the addition of C₂H₆ and H₂ does not change the main CH₄ oxidisation pathways. The decomposition of these additives provides additional ignition-promoting radicals, and therefore leads to shorter ignition delays. N₂ additives do not alter the CH₄ oxidisation pathways, however, they reduce the amount of CH₄ available for reaction, causing delayed ignition. It is further shown that ignition always occurs in lean mixtures and at low scalar dissipation rates. The second study is concerned with the modelling of a piloted CH₄/air turbulent jet flame. A detailed assessment of several Probability Density Function (PDF), Conditional Scalar Dissipation Rate (CSDR) and Conditional Velocity (CV) submodels is first performed. The results of two β-PDF-based implementations are then presented. The two realisations differ by the modelling of the CSDR. Homogeneous (inconsistent) and inhomogeneous (consistent) closures are considered. It is shown that the levels of all reactive scalars, including minor intermediates and radicals, are better predicted when the effects of inhomogeneity are included in the modelling of the CSDR. The two following studies are focused on the consistent modelling of a lifted H₂/N₂ turbulent jet flame issuing into a vitiated coflow. Two approaches are followed to model the PDF. In the first, a presumed β-distribution is assumed, whereas in the second, the Presumed Mapping Function (PMF) approach is employed. Fully consistent CV and CSDR closures based on the β-PDF and the PMF-PDF are employed. The homogeneous versions of the CSDR closures are also considered in order to assess the effect of the spurious sources which stem from the inconsistent modelling of mixing. The flame response is analysed over a narrow range of coflow temperatures (Tc). The stabilisation mechanism is determined from the analysis of the transport budgets in mixture fraction and physical spaces, and the history of radical build-up ahead of the stabilisation height. The β-PDF realisations indicate that the flame is stabilised by autoignition irrespective of the value of Tc. On the other hand, the PMF realisations reveal that the stabilisation mechanism is susceptible to Tc. Autoignition remains the controlling stabilisation mechanism for sufficiently high Tc. However, as Tc is decreased, stabilisation is achieved by means of premixed flame propagation. The analysis of the spurious sources reveals that their effect is small but non-negligible, most notably within the flame zone. Further, the assessment of several H₂ oxidation mechanisms show that the flame is very sensitive to chemical kinetics. In the last study, a DCMC method is proposed for the treatment of fluctuations in non-premixed and partially premixed turbulent combustion. The classical CMC theory is extended by introducing a normalised Progress Variable (PV) as a second conditioning variable beside the mixture fraction. The unburnt and burnt states involved in the normalisation of the PV are specified such that they are mixture fraction-dependent. A transport equation for the normalised PV is first obtained. The doubly-conditional species, enthalpy and temperature transport equations are then derived using the decomposition approach and the primary closure hypothesis is applied. Submodels for the doubly-conditioned unclosed terms which arise from the derivation of DCMC are proposed. As a preliminary analysis, the governing equations are simplified for homogeneous turbulence and a parametric assessment is performed by varying the strain rate levels in mixture fraction and PV spaces.
10

Conditional Moment Closure Methods for Turbulent Combustion Modelling

El Sayed, Ahmad 18 March 2013 (has links)
This thesis describes the application of the first-order Conditional Moment Closure (CMC) to the autoignition of high-pressure fuel jets, and to piloted and lifted turbulent jet flames using classical and advanced CMC submodels. A Doubly-Conditional Moment Closure (DCMC) formulation is further proposed. In the first study, CMC is applied to investigate the impact of C₂H₆, H₂ and N₂ additives on the autoignition of high-pressure CH₄ jets injected into lower pressure heated air. A wide range of pre-combustion air temperatures is considered and detailed chemical kinetics are employed. It is demonstrated that the addition of C₂H₆ and H₂ does not change the main CH₄ oxidisation pathways. The decomposition of these additives provides additional ignition-promoting radicals, and therefore leads to shorter ignition delays. N₂ additives do not alter the CH₄ oxidisation pathways, however, they reduce the amount of CH₄ available for reaction, causing delayed ignition. It is further shown that ignition always occurs in lean mixtures and at low scalar dissipation rates. The second study is concerned with the modelling of a piloted CH₄/air turbulent jet flame. A detailed assessment of several Probability Density Function (PDF), Conditional Scalar Dissipation Rate (CSDR) and Conditional Velocity (CV) submodels is first performed. The results of two β-PDF-based implementations are then presented. The two realisations differ by the modelling of the CSDR. Homogeneous (inconsistent) and inhomogeneous (consistent) closures are considered. It is shown that the levels of all reactive scalars, including minor intermediates and radicals, are better predicted when the effects of inhomogeneity are included in the modelling of the CSDR. The two following studies are focused on the consistent modelling of a lifted H₂/N₂ turbulent jet flame issuing into a vitiated coflow. Two approaches are followed to model the PDF. In the first, a presumed β-distribution is assumed, whereas in the second, the Presumed Mapping Function (PMF) approach is employed. Fully consistent CV and CSDR closures based on the β-PDF and the PMF-PDF are employed. The homogeneous versions of the CSDR closures are also considered in order to assess the effect of the spurious sources which stem from the inconsistent modelling of mixing. The flame response is analysed over a narrow range of coflow temperatures (Tc). The stabilisation mechanism is determined from the analysis of the transport budgets in mixture fraction and physical spaces, and the history of radical build-up ahead of the stabilisation height. The β-PDF realisations indicate that the flame is stabilised by autoignition irrespective of the value of Tc. On the other hand, the PMF realisations reveal that the stabilisation mechanism is susceptible to Tc. Autoignition remains the controlling stabilisation mechanism for sufficiently high Tc. However, as Tc is decreased, stabilisation is achieved by means of premixed flame propagation. The analysis of the spurious sources reveals that their effect is small but non-negligible, most notably within the flame zone. Further, the assessment of several H₂ oxidation mechanisms show that the flame is very sensitive to chemical kinetics. In the last study, a DCMC method is proposed for the treatment of fluctuations in non-premixed and partially premixed turbulent combustion. The classical CMC theory is extended by introducing a normalised Progress Variable (PV) as a second conditioning variable beside the mixture fraction. The unburnt and burnt states involved in the normalisation of the PV are specified such that they are mixture fraction-dependent. A transport equation for the normalised PV is first obtained. The doubly-conditional species, enthalpy and temperature transport equations are then derived using the decomposition approach and the primary closure hypothesis is applied. Submodels for the doubly-conditioned unclosed terms which arise from the derivation of DCMC are proposed. As a preliminary analysis, the governing equations are simplified for homogeneous turbulence and a parametric assessment is performed by varying the strain rate levels in mixture fraction and PV spaces.

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