125f. / Submitted by Suelen Reis (suziy.ellen@gmail.com) on 2013-04-16T18:59:20Z No. of bitstreams: 1 Pedro Jonas de Almeidaseg.pdf: 626207 bytes, checksum: b1c9c6b10c3fd4389fef3a65e82a8613 (MD5) / Approved for entry into archive by Rodrigo Meirelles(rodrigomei@ufba.br) on 2013-05-16T17:37:25Z (GMT) No. of bitstreams: 1 Pedro Jonas de Almeidaseg.pdf: 626207 bytes, checksum: b1c9c6b10c3fd4389fef3a65e82a8613 (MD5) / Made available in DSpace on 2013-05-16T17:37:25Z (GMT). No. of bitstreams: 1 Pedro Jonas de Almeidaseg.pdf: 626207 bytes, checksum: b1c9c6b10c3fd4389fef3a65e82a8613 (MD5) Previous issue date: 2007 / Ao deslocar a necessidade causal das coisas para o espírito, Hume dá uma nova definição de necessidade. Enquanto a tradição filosófica a definia como um liame objetivo e interno entre a causa e o efeito, Hume a define como um sentimento imediato de determinação na mente que nos leva a passar de uma idéia àquela que lhe é habitualmente associada. Este sentimento será transferido como uma força, como uma vivacidade que irá carregar a segunda idéia. Esta idéia assim avivada será chamada de crença no Tratado da Natureza Humana. A crença é uma maneira de conceber uma idéia, uma maneira mais vívida de concebê-la. Além disso, para que uma idéia ganhe vivacidade é preciso que haja uma relação de semelhança entre os casos observados ou associados na imaginação. Ora, em virtude da determinação imediata no espírito, a crença se dá mesmo quando não há uma semelhança completa entre os casos. Hume acrescenta, então, uma outra operação para regular esse mecanismo automático: a reflexão. Essa operação irá nos remeter à teoria das regras gerais, indispensável para uma compreensão adequada do projeto de Hume. No sistema moral do livro 3 será esta a operação responsável pela estabilização do juízo moral. A afetividade e a reflexão constituem, assim, a unidade do Tratado. Esses dois componentes da natureza humana se articulam ainda em uma teoria das paixões que, como diz Hume, é a pesquisa principal de sua filosofia desde o livro 1. A fantasia, por sua vez, irá aparecer no Tratado seja enquanto fator de desestabilização da crença, exigindo uma operação reflexiva ou corretiva do entendimento, seja enquanto fator criador de regras artificiais úteis à sociedade. Por isso, suas funções não possuem o mesmo valor e sentido. No livro1, ela ameaça de dentro a ciência, as inferências legítimas. Nos livros 2 e 3, ela possui uma positividade, subordinada apenas à utilidade de suas regras para a estabilidade social. Essa utilidade depende também de uma reflexão sobre as tendências dessas regras artificiais de promover a ordem e a estabilidade sociais. Hume se apresenta como o Newton das ciências morais. Seu empreendimento é científico nesse novo sentido de ciência experimental. Sua física do homem descreve este último como um animal governado por princípios gerais de associação de idéias e de paixões, assim como por instintos. / Salvador

Com esta pesquisa busquei constituir cenários para investigação para as aulas de matemática a partir da produção decorrente de pesquisas realizadas no Projeto de Iniciação Científica no Instituto Federal de Educação, Ciência e Tecnologia Catarinense - Campus Rio do Sul. Para atingir os objetivos propostos por esta pesquisa, elaborei uma possibilidade educacional através da investigação de situações-problema da vida real, o que possibilitou identificar e significar os conceitos matemáticos em análise. A pesquisa foi embasada na teoria da Transposição Didática, discutida por Chevallard, com o intuito de auxiliar no trabalho de adaptar e transformar os conhecimentos produzidos em projetos de Iniciação Científica para um conhecimento que possa ser desenvolvido e produzido em sala de aula. Para que a transposição viesse acontecer num viés reflexivo procurei discutir a Educação Matemática Crítica, segundo Skovsmose. Provocando assim, uma reflexão sobre os conteúdos matemáticos envolvidos e a realidade inerente ao contexto. Ao procurar interagir os pressupostos teóricos com a realidade, atingi o objetivo da pesquisa e denominei este trabalho de Transposição Didática Reflexiva, com o intuito de unir as duas teorias num processo em que o saber a ser ensinado seja adaptado de forma a provocar reflexões, instituindo um cenário para investigação que propicie a participação do aluno no processo, provoque discussões e tomada de decisão, de modo a instigar o sujeito a ser transformador de sua própria realidade. Adotei na pesquisa uma abordagem qualitativa e para a coleta de dados desenvolvi a possibilidade educacional com as primeiras séries do Ensino Médio, observando as atitudes e considerações dos alunos perante as atividades propostas. Também apresento um quadro de limitações que permearam a proposta e como produto final, apresento três propostas de roteiros de aprendizagem que visam subsidiar outros professores que desejem desenvolver possibilidades educacionais, num viés que possibilite a constituição de um cenário para investigação de modo a instigar a curiosidade, o espírito investigativo e a criticidade dos sujeitos envolvidos no processo pedagógico. / Through this work I aimed at building investigative sceneries for the mathematics lessons from the current researches development carried through the Scientific Initiation Project of the Catarinense Federal Institute of Education, Science and Technology - Campus of Rio do Sul. In order to reach the objectives set for this research, I developed an educational possibility through the investigation of real life problem-situations, which allowed me to identify and make sense of the analyzed mathematical concepts. The research was based on the Didactic Transposition theory - stated by Chevallard - aiming at getting support to the work in order to adapt and transform the knowledge produced with the projects of Scientific Initiation into a knowledge that can be developed and be produced into the classroom. So that the transposition happened into a reflective bias I tried to discuss the Critical Mathematical Education in accordance with Skovsmose, then bringing a reflection on the involved mathematical contents and the reality inherent to the context. When aiming at getting the interaction between the theoretical presuppositions and the reality, I reached the objective of this research and named this work as Reflective Didactic Transposition, intending to join the two theories into a process in which the knowledge to be taught be adapted to be reflectionsprovoking offering an investigation scenery that propitiates the participation of the student into the process and bringing discussions and decision taking, instigating the student - as an individual - to be the one who transforms his/her own reality. I used a qualitative approach in the research, and for the data collection I implemented the educational possibility at Junior High School classes, observing the attitudes and considerations of the students face the proposed activities as well. I also present a limitations figure that interfered with the proposal, and as the final result I present three learning approaches aimed at subsidizing other teachers who want to develop educational possibilities on a bias that turn into possible the constitution of a research scenery in order to instigate the curiosity, the investigative spirit and the critical view of the individuals involved in the pedagogical process.

Light reflection from the glass surface of a photovoltaic (PV) module is a significant source of energy loss for all types of PV devices. The reflection at the glass and air interface accounts for ~4% of the total energy. Single layer anti-reflection coatings with sufficiently low refractive index have been used, such as those using magnesium fluoride or porous silica, but these are only effective over a narrow range of wavelengths. Multilayer-antireflection coatings reduce the weighted average reflection over the wavelength range used by solar technologies more effectively by utilising interference effects. Multilayer stacks consisting of silica and zirconia layers deposited using reactive magnetron sputtering and single layer porous silica coatings were compared in terms of effectiveness and durability. Details of the stack design, sputter deposition process parameters, and the optical and micro-structural properties of the layers of the multilayer coating are provided and similar properties where applicable for the single layer coatings. Anti-reflection coatings on glass exposed to the outdoors must not degrade over the lifetime of the module. A comprehensive set of accelerated environmental durability tests has been carried out in accordance with IEC 61646 PV qualification tests. The durability tests confirmed no damage to the coatings or performance drop as a result of thermal cycling or damp heat. All attempts to perform pull tests on either coating resulted in either adhesive or substrate failure, with no damage to the coating itself. Scratch resistance, abrasion resistance, and adhesion tests have also been conducted. The optical performance of the coatings was monitored during these tests and the coatings were visually inspected for any sign of mechanical failure. These tests provide confidence that broadband anti-reflection coatings are highly durable and will maintain their performance over the lifetime of the solar module. Additionally heat treatment experiments demonstrated both coatings can withstand up to 600°C temperatures and can thereby withstand CdTe manufacturing processes allowing for pre-coated glass. Additionally experiments demonstrated that multi-layer coatings are resistant to acid attack. Thin film photovoltaic devices are multilayer opto-electrical structures in which light interference occurs. Light reflection at the interfaces and absorption within the window layers reduces transmission and, ultimately, the conversion efficiency of photovoltaic devices. Optical reflection losses can be reduced by adjusting the layer thicknesses to achieve destructive interference within the structure of the cell. The light transmission to the CdTe absorber of a CdS/CdTe cell on a fluorine doped tin oxide transparent conductor has been modelled using the transfer matrix method. The interference effect in the CdS layer and high resistance transparent buffer layers (SnO2 and ZnO) has been investigated. The modelling shows that due to relatively high absorption within the SnO2 layer, there are modest benefits to engineering anti-reflection interference in the stack. However, a ZnO buffer layer has limited absorption and interference can be exploited to provide useful anti-reflection effects. Additionally the light transmission to the perovskite absorber of a thin film solar cell using fluorine doped tin oxide (FTO) transparent conductor has been modelled. Alternative transparent conductor materials have also been investigated including aluminium doped zinc oxide (AZO) and indium tin oxide (ITO) and shown to be beneficial to transmission.

With the rise of the writing-to-learn (WTL) movement, studies on reflection and implementing reflective writing became key focal points in research on writing across the curriculum (WAC). Scholars from a wide range of disciplines have noted the benefits of implementing genres of writing that prompt students to look back and assess aspects of their own performance and understanding. Other inquiries examine if reflective writing impacts student performance, as well as analyze students' reflective processes and their perceptions of reflection. This investigation represents a continuation and expansion of these different research efforts on reflection across the curriculum. The goal of this work is to gain more knowledge about students' reflective processes and the language that they use to describe reflective thought and action by focusing on multiple, discipline-specific contexts. Through an exploratory study of four courses within two disciplines--English and History--at a large, public university, this work examines the reflective processes and perceptions of students and how their perceptions and processes align with their instructors' expectations. This study suggests that students and instructors in various disciplines have unique and sometimes divergent ways of using and talking about reflection, which presents implications for research on WAC and knowledge transfer. Aligning with the rich body of research in the field, this investigation uses reflection as both a subject of inquiry and a guiding action.

A two square mile (5.2 square kilometer) 3-D seismic reflection survey was completed in northeastern White County, Illinois for petroleum exploration in January of 2008. Well log data was made available from Royal Drilling and Producing, who contracted the seismic survey, and additional data was retrieved from the ILOIL database. Raster (TIFF format) images that were available for nearly every well location in the study area were calibrated for depth and stratigraphic tops picked. The purpose of this study is to analyze the Aux Vases formation using 3-D seismic reflection data and attribute analysis by comparing this data to well log information that is greatly available in the study area. Synthetic seismograms were calculated to calibrate seismic reflection data time to actual geological depth to a formation. The synthetic seismograms were calculated using wavelets extracted from the 3-D seismic data and edited, digital (LAS format) sonic and density logs measured in three wells. Geophysical log data from wells in the area were used to interpret formation top and bottoms. With the Aux Vases and Ste. Genevieve top information, an isopach was generated. Horizons were handpicked in all 318 seismic lines and isochron maps were generated to compare time thickness to actual thickness of the isopach maps. Attribute analysis was performed on horizon and volume cubes to interpret the Aux Vases formation in the study area. These attributes included instantaneous phase, instantaneous amplitude, and instantaneous frequency. Additionally, multiple spectral decomposition cubes (from four SEG-Y volumes) were generated for 520-580 ms intervals and interpreted at 550 ms. The combination of this data lead to identification of two larger stratigraphic bodies and several smaller ones in the study area. Thickness comparison between these attributes and isopach maps was completed and found similarities that can be used to determine potential thickness. A thickness estimate was completed at Well B using the frequency from spectral decomposition. A channel was mapped in the western edge of the survey using spectral decomposition and other attributes. Finally, a fault was identified in the southeastern portion of the survey area.

In 2011 and 2012 a Vibroseis™ seismic reflection survey, consisting of one westeast and one north-south seismic reflection profile, was conducted near the community of Aden (Hamilton County), Illinois, for hydrocarbon exploration purposes. Previous interpretations of the west-east seismic line (Ranaweera, 2015), as well as drill cuttings (Cantrell, 2011) from a nearby well (Webb #1), indicated the existence of a mud-mound within the Ullin Limestone. This thesis studied the shape and dimensions, as well as the seismic velocity properties, of the Aden mud-mound by re-processing and interpreting the Aden seismic reflection data. The interpretation process was aided by constructing two-dimensional synthetic seismograms from well log data from the nearby Broughton and Johnsonville oil fields, which are known locations of Waulsortian mud-mounds similar to the one inferred to exist at Aden. The results of this investigation indicate that the Aden mudmound has a longitudinal extent of approximately 0.6 miles (0.97 km) wide across the west-east ADEN #1 profile. From north-to-south on the ADEN #2 profile, the feature is approximately 0.7 miles (1.13 km) long. The geologic feature is located within the Ullin Limestone (Lower Mississippian) and is only manifested by the draping of younger strata overlying the mud-mound as observed on the seismic reflection images. Results from the 2D synthetic seismograms indicate that the seismic reflections generated across the known mud-mounds at Broughton and Johnsonville are similar to the seismic reflections seen at the location of the interpreted mud-mound on the Aden seismic reflection data. The presence of the Aden mud-mound is inferred by the draping of overlying strata above the mud-mound. This is interpreted to be caused by the increase in stratigraphic relief at the top of the Ullin, which becomes thicker at the mud-mound locations. Geologic and well log data from drill holes at Aden revealed that the interpreted Aden mud-mound formed in the Harrodsburg Member of the Ullin Limestone. The Harrodsburg is approximately 90 feet (27 meters) thick at Aden but becomes thicker at the location Webb #1 (up to 152 feet) where the mud-mound is located, indicating that the Aden mud-mound is at least 152 feet thick, when measured from the base of the Harrodsburg Member. A study of Root-Mean-Squared (RMS) and interval velocities, derived from sonic and pseudo-sonic log data from wells from the Aden, Broughton, and Johnsonville locations, indicated that RMS and interval velocities from the upper member (Harrodsburg Member) of the Ullin Limestone are higher than RMS and interval velocities present in the lower member (Ramp Creek Member) of the Ullin. Stacking velocities derived from the Aden seismic reflection data matched the RMS velocity values derived from sonic log data from drill holes at Aden with percent differences of less than 5%. This study indicates that stacking velocities at this location are accurate enough (within approximately 5%) to perform velocity studies when well log data from drill holes are not available. Additionally, there were no significant variations in stacking velocity profiles in the Ullin Limestone atthe Aden mud-mound location when compared to stacking velocity profiles derived at CMP locations away from the mud-mound. Likewise, there were no significant variations between RMS and Interval velocity profiles of the Ullin Limestone, derived from wells that were drilled into mud-mound locations at Aden, Broughton, and Johnsonville, and RMS and interval velocity profiles derived from wells that were drilled away from the mud-mound locations. The conclusion of this study is that RMS and interval velocity profiles, as well as stacking velocity profiles from seismic reflection data, are not good indicators for pinpointing the existence and location of carbonate mud-mounds. The best method to identify such carbonate structures is by interpreting their structure observed on seismic reflection records, including the draping effect on shallow reflections above the mudmound as observed in the recorded seismic reflection data, and by analyzing drill cuttings if available.

Made available in DSpace on 2014-06-11T19:25:27Z (GMT). No. of bitstreams: 0 Previous issue date: 2004-05-03Bitstream added on 2014-06-13T18:53:28Z : No. of bitstreams: 1 marinho_br_me_assis.pdf: 371222 bytes, checksum: 584fa3c529b03ffe81253fe15993665d (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O objetivo desta pesquisa é viabilizar a produção de outros modos de pensar a educação de professores de línguas estrangeiras. Buscamos construir contextos não convencionais de pesquisa nos quais os profissionais possam refletir acerca de sua experiência de ensino/aprendizagem de línguas. Para tanto, nos baseamos metodologicamente na Pesquisa Educacional com Base nas Artes (Eisner, 1991)cujo recurso principal é um espetáculo teatral, denominado Parâmetros em Análise. Tal espetáculo foi construído a partir de temas inspirados nos Parâmetros Curriculares Nacionais. Foram apresentados dez espetáculos em diversas instituições das redes de ensino oficial e particulares do Estado de São Paulo. No palco do espetáculo, foram representadas, artisticamente, cenas do dia-a-dia e do fazer pedagógico dos professores de línguas estrangeiras, assim como, os seus conflitos e dilemas profissionais. Após o espetáculo ocorreu uma reflexão crítica compartilhada entre a platéia composta por professores, educadores de professores e alunos de Letras. O espetáculo e a reflexão compõem aquilo que Foucault (Deleuze, 1988) conceitua como sendo um dispositivo. Para o filósofo, dispositivos são máquinas de fazer ver e falar. Eles formam uma espécie de instrumento teórico com o qual contamos para visualizar as práticas sociais que se dão na escola. As reflexões realizadas pelos professores indicam um desencontro entre aquilo que professores e alunos estão atualizando nas suas práticas e, aquilo que propõem certas pesquisas, políticas educacionais e o funcionamento da estrutura institucional da escola. / The objective of this paper is to make the production of other ways of thinking over education of foreign language teachers possible. We intend to construct non-conventional contexts of research, in which the professionals can think over their language learning/teaching experiences. For that, we are based methodologically on the Educational Research based on Arts (Eisner, 1991) whose chief resource is the dramatic performance, called Patterns in Analysis. Such performance was built from themes inspired in the Parâmetros Curriculares Nacionais. Ten performances were acted in several public and private institutions of education in the State of São Paulo. On the stage, everyday scenes and the pedagogical work of foreign language teachers were acted artistically, such as, their conflicts and professional dilemmas. After the performance, a critical reflection shared by the audience composed by teachers, teachers' professors and students took place. The performance and the reflection compose what Foucault (Deleuze, 1988) considers as a device. To the philosopher, devices are machines of making see and speak. They constitute a theoretical instrument that we use to analyze the social experiences that happen at schools. The reflections arisen by the teachers indicate a discordance from what teachers and students have been passing through a process of modification in their experiences and, from what some researches, educational policies and the operation of the institutional structure of the school propose.

Wireless communication today is a modern way to transport data from one location to another. One of the drawbacks of this feature is that a signal jammer can disrupt communications between the receiver and transmitter since the radio waves travel in the open air. This drawback can be exploited in both military and civilian applications. This thesis will aim on how to locate this kind of transmitting signal jammer over an open field using an Unmanned Aerial Vehicle (UAV) that searches the designated area with the assumption of line of sight between the UAV and the transmitting jammer. Two different methods will be investigated with different techniques, antennas and flight patterns. / Trådlös kommunikation idag är den moderna tidens sätt att transportera data från en plats till en annan. En nackdel med det är att en störsändare kan förhindra kommunikation mellan den sändande och mottagande antennen. Denna nackdel kan utnyttjas både inom militära och civila tillämpningar. Detta examensarbete undersöker två metoder för att lokalisera en störsändare över ett öppet fält med hjälp av en drönare, då fri sikt råder mellan drönare och störsändare. Dessa två olika metoder är baserade på olika tekniker, antenner och flygmönster.

Com esta pesquisa busquei constituir cenários para investigação para as aulas de matemática a partir da produção decorrente de pesquisas realizadas no Projeto de Iniciação Científica no Instituto Federal de Educação, Ciência e Tecnologia Catarinense - Campus Rio do Sul. Para atingir os objetivos propostos por esta pesquisa, elaborei uma possibilidade educacional através da investigação de situações-problema da vida real, o que possibilitou identificar e significar os conceitos matemáticos em análise. A pesquisa foi embasada na teoria da Transposição Didática, discutida por Chevallard, com o intuito de auxiliar no trabalho de adaptar e transformar os conhecimentos produzidos em projetos de Iniciação Científica para um conhecimento que possa ser desenvolvido e produzido em sala de aula. Para que a transposição viesse acontecer num viés reflexivo procurei discutir a Educação Matemática Crítica, segundo Skovsmose. Provocando assim, uma reflexão sobre os conteúdos matemáticos envolvidos e a realidade inerente ao contexto. Ao procurar interagir os pressupostos teóricos com a realidade, atingi o objetivo da pesquisa e denominei este trabalho de Transposição Didática Reflexiva, com o intuito de unir as duas teorias num processo em que o saber a ser ensinado seja adaptado de forma a provocar reflexões, instituindo um cenário para investigação que propicie a participação do aluno no processo, provoque discussões e tomada de decisão, de modo a instigar o sujeito a ser transformador de sua própria realidade. Adotei na pesquisa uma abordagem qualitativa e para a coleta de dados desenvolvi a possibilidade educacional com as primeiras séries do Ensino Médio, observando as atitudes e considerações dos alunos perante as atividades propostas. Também apresento um quadro de limitações que permearam a proposta e como produto final, apresento três propostas de roteiros de aprendizagem que visam subsidiar outros professores que desejem desenvolver possibilidades educacionais, num viés que possibilite a constituição de um cenário para investigação de modo a instigar a curiosidade, o espírito investigativo e a criticidade dos sujeitos envolvidos no processo pedagógico. / Through this work I aimed at building investigative sceneries for the mathematics lessons from the current researches development carried through the Scientific Initiation Project of the Catarinense Federal Institute of Education, Science and Technology - Campus of Rio do Sul. In order to reach the objectives set for this research, I developed an educational possibility through the investigation of real life problem-situations, which allowed me to identify and make sense of the analyzed mathematical concepts. The research was based on the Didactic Transposition theory - stated by Chevallard - aiming at getting support to the work in order to adapt and transform the knowledge produced with the projects of Scientific Initiation into a knowledge that can be developed and be produced into the classroom. So that the transposition happened into a reflective bias I tried to discuss the Critical Mathematical Education in accordance with Skovsmose, then bringing a reflection on the involved mathematical contents and the reality inherent to the context. When aiming at getting the interaction between the theoretical presuppositions and the reality, I reached the objective of this research and named this work as Reflective Didactic Transposition, intending to join the two theories into a process in which the knowledge to be taught be adapted to be reflectionsprovoking offering an investigation scenery that propitiates the participation of the student into the process and bringing discussions and decision taking, instigating the student - as an individual - to be the one who transforms his/her own reality. I used a qualitative approach in the research, and for the data collection I implemented the educational possibility at Junior High School classes, observing the attitudes and considerations of the students face the proposed activities as well. I also present a limitations figure that interfered with the proposal, and as the final result I present three learning approaches aimed at subsidizing other teachers who want to develop educational possibilities on a bias that turn into possible the constitution of a research scenery in order to instigate the curiosity, the investigative spirit and the critical view of the individuals involved in the pedagogical process.

Um dos problemas técnicos que ocorrem nos revestimentos cerâmicos é a possibilidade de duas peças serem da mesma cor sob a luz do dia, mas de cores diferentes sob outra iluminação. Tal fenômeno é chamado metamerismo. O presente trabalho teve como objetivo realizar um estudo sobre a influência de variáveis do processo de fabricação de revestimentos cerâmicos na ocorrência do fenômeno de metamerismo, tendo como objeto de estudo uma peça monoporosa de esmalte branco-brilhante, e um porcelanato mate. Para tanto, avaliou-se o efeito da variação de iluminante, correlacionado com as seguintes características dos revestimentos cerâmicos investigados: i) tipologia de esmalte; ii) base, engobe esmaltes; iii) variação de camada; iv) utilização de quartzo, caulim e zirconita; v) variação de corantes. Os resultados mostraram que esmaltes, como o branco-brilhante, se destacam no aparecimento da característica metamérica, tanto mais quanto mais espessa a camada. Já, quando se aumenta a camada do mate, este fenômeno ameniza. A zirconita, por ser um opacificante, ameniza a reflexão da luz, gerando uma diminuição do metamerismo. O quartzo promove o metamerismo, já que influencia no aparecimento do brilho. Quanto aos corantes, pigmentos que amenizam o reflexo da luz, como o preto e cinza, possuem um valor metamérico baixo, já pigmentos que tendem ao reflexo maior da luz, promovem o metamerismo. Com base nisso, o suporte do porcelanato esmaltado que se apresenta em uma base cinza, possui um valor metamérico menor que a base da monoporosa, que possui uma cor bege. Ficou evidenciada a influência das curvas espectrais e do reflexo no aparecimento do metamerismo, podendo ser um ponto crucial para que empresas trabalhem em cima deste problema, a fim de ser um diferencial para seus clientes no mercado competitivo como o de hoje. / One of several problems that occur in ceramic tiles, is the possibility that two objects are the same color in the light of day, but of different colors in a different light. This phenomenon, in which two colors are similar under a light source but different under another, is called metamerism. Seeking a study on this phenomenon was analyzed the influence of some variables on the metamerism in a white enamel-bright monoporosity, and a matte porcelain. Some of the variables selected for the study of the influence of the media, and enamel on engobe metamerism, the addition of opacifier material, in suspension and bright enamels in different percentages, the analysis with the addition of pure colors and mixtures of the same in glazes; variations in the enamel layer, among other factors. Before, it was noticed that the enamel provide a high spectral curve, ie, materials that reflect the highly light, tend to influence the onset of this phenomenon. Thus, materials that influence the formation of brightness as quartz help this phenomenon to emerge since opacifying materials that have the feature to break it brightness, ie, which have lower spectral curves, decreases the appearance of this phenomenon. In the matter of color is the same as explained above, ie, pigments that mitigate the reflection of light as the black and gray, have a low value metameric because colors tend to reflect more light, raise this value. On this basis, the support of porcelain enamel that comes in on a gray metameric has a value less than the base of monoporosity, which has a beige color. Having knowledge of these factors, it is clear the influence of spectral curves and reflex formed by these variables in the emergence of this phenomenon and may be a crucial point for companies to work upon this problem, in order to be a differentiator for its customers in competitive market which is today.