Made available in DSpace on 2014-06-11T19:28:55Z (GMT). No. of bitstreams: 0 Previous issue date: 2003-02-18Bitstream added on 2014-06-13T19:16:52Z : No. of bitstreams: 1 pavan_s_me_arafo.pdf: 776969 bytes, checksum: 2a333e8745a98776862d0b115402f9c3 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O objetivo deste estudo foi avaliar o efeito de técnicas de desinfecção utilizando soluções de glutaraldeído 2%, hipoclorito de sódio 5%, clorexidina 5% e energia por microondas sobre a dureza e rugosidade de superfície dos materiais reembasadores macios Ufi Gel , Molloplast-B, Eversoft e Mucopren soft. Quarenta corpos-de-prova de cada material com dimensões de 36x7x6 mm foram processados em muflas plásticas para microondas e polimerizados de acordo com as recomendações dos fabricantes. As amostras foram divididas em grupos (n=10) e submetidas à desinfecção por 10 minutos nas soluções químicas e, em forno de microondas doméstico por período de 3 minutos à 500W. As leituras de dureza e rugosidade foram realizadas 24 horas após a confecção dos corpos de prova e após aplicação do 1° e 2° ciclo de desinfecção, respectivamente. As leituras de dureza foram realizadas sobre uma das faces do corpo de prova com auxílio de durômetro Shore A. Sobre a face oposta foram realizadas as leituras de rugosidade com rugosímetro Surf-Corder SE 1700. Os dados obtidos foram submetidos à análise de variância e teste de Tukey ao nível de significância de 1%. Conclui-se que a aplicação de dois ciclos de desinfecção não produziu alterações na dureza dos materiais utilizados. Porém, houve diminuição na rugosidade após o primeiro ciclo de desinfecção. A técnica de desinfecção com solução de glutaraldeído 2% promoveu os maiores valores de dureza nos materiais Molloplast-B, Mucopren soft e Ufi Gel. Já o material Eversoft não apresentou alteração nos valores de dureza e rugosidade de superfície em nenhuma das técnicas de desinfecção. / The aim of this study was to assess the effect of disinfections with 2% glutaraldehyde, 5% sodium hypoclorite, 5% chlorhexidine solution and microwave oven on hardness and roughness of soft denture liners Ufi Gel, Molloplast-B, Eversoft and Mucopren soft. Forty samples (36x7x6 mm) of each material were processed in special microwave flasks according to manufacturers' recommendation. Ten specimens of each material were immersed in each disinfectant solution for ten minutes or placed in a microwave oven for 3 minutes at 500W. The surface roughness and hardness values were recorded after 24 hours (control), and also at each two cycles of disinfection. Hardness readings were made on the sample surface with Shore A durometer according to the ASTM D-2240 specifications. The surface roughness was verified on the other surface using a Surf-Coder SE 1700 perfilometer. Data were submitted at analysis of variance and Tukey's test to 1% of level. The application of two disinfection cycles did not change the hardness values significantly. However, after the first cycle of disinfection, means of surface roughness were lower than those observed for the control. The glutaraldehyde solution promoted the highest values of hardness on Molloplast-B, Mucopren soft and Ufi Gel materials. The Eversoft did not show changes in hardness and surface roughness independent of disinfection technique.

Made available in DSpace on 2014-06-11T19:28:56Z (GMT). No. of bitstreams: 0 Previous issue date: 2003-02-27Bitstream added on 2014-06-13T20:58:46Z : No. of bitstreams: 1 ticianeli_mg_me_arafo.pdf: 1350387 bytes, checksum: ea0f36454c6c9f5c29da9a1476668be1 (MD5) / Este estudo avaliou a eficiência de diferentes técnicas de acabamento e polimento sobre duas cerâmicas odontológicas (Duceram Plus e Duceram LFC), em relação à rugosidade média superficial (Ra). Foram preparados quarenta discos com 8 mm de diâmetro e 4 mm de espessura para cada uma das cerâmicas utilizadas, seguindo-se as recomendações do fabricante. Previamente ao glazeamento, todos os corpos-de-prova foram regularizados com o auxílio de lixas d'água de diferentes granulações (240,360 e 600, nesta ordem), recebendo, em seguida, uma camada de glaze. Os 40 corpos-de-prova de cada cerâmica foram divididos em 8 grupos com 5 representantes em cada um, recebendo diferentes tratamentos de superfície: T1- glaze; T2- desgaste com ponta diamantada fina e ultrafina; T3- T2 + sistema de acabamento e polimento dental Sof-Lex (3 M); T4- T3 + pasta diamantada; T5- T2 + kit de polimento Super-Snap (Shofu); T6- T5 + pasta diamantada; T7- T2 mais borrachas abrasivas Viking (KG Sorensen); T8- T7 + pasta diamantada. Foram realizadas cinco mensurações de rugosidade média (Ra, em æm) em cada corpo-de-prova, utilizando-se um rugosímetro ajustado com cut-off de 0,25 mm, extensão de tracejamento de 1,25 mm e velocidade de medição de 0,10 mm/s. Os resultados foram analisados estatisticamente pelos testes ANOVA e Tukey, com nível de significância de 5%. Os melhores tratamentos para ambas as cerâmicas avaliadas foram T3, T4, T5 e T6, apresentando semelhança estatística entre si; O glazeamento (T1) foi similar estatisticamente aos tratamentos T3, T4, T5 e T6 para a cerâmica Duceram LFC, em relação ao fator Ra; O tratamento T1 apresentou-se com diferença estatisticamente significante e mais rugoso que o tratamento T3, T4 e T6 para a cerâmica Duceram Plus, em relação ao fator Ra; As duas cerâmicas odontológicas avaliadas apresentaram... / This study assessed the efficacy of different current porcelain finishing and polishing procedures on two different dental ceramic (Duceram Plus and Duceram LFC) quantitatively with a profilometer. Forty disks (8 mm in diameter and 4 mm thick) were prepared for each dental ceramic according to the manufacturer's directions. Prior to glazing, all specimens' surfaces were abraded using a 240, 360 and 600-grit wet sandpaper. Then, all samples were glazed. The forty samples of each dental ceramic were divided into 8 groups of five specimens each, according to the surface treatment: T1- glaze; T2- abraded with fine and ultra fine diamond burs (KG Sorensen); T3- T2 following Sof-Lex (3M) polishing system; T4- T3 following diamond paste; T5- T2 following Super-Snap polishing kit (Shofu); T6- T5 following diamond paste; T7- Viking rubber wheels (KG Sorensen); T8- T7 following diamond paste. Five roughness measurements (Ra, æm) were performed on each disc using a profilometer with cut-off value of 0.25 mm and a tracing length of 1.25 mm and a speed of 0.1 mm per second. These values were tested using a two-way analysis of variance and Tukey test at 5% significance level. The result showed (to Ra factor) that T3, T4, T5 and T6 were the best surface treatment for both dental ceramic materials and were statistically equals; the glazed treatment (T1) was similar statistically to the polishing treatment T3, T4, T5 and T6 for Duceram LFC ceramic; the glazed treatment (T1) was different statistically and rougher than the polishing treatment T3, T4 e T6 for Duceram Plus ceramic; the two different dental ceramic had similar behavior when received the same surface treatment; and the diamond-abraded group (T2) had the rougher surface in both dental ceramic studied.

abstract: CMOS technology is expected to enter the 10nm regime for future integrated circuits (IC). Such aggressive scaling leads to vastly increased variability, posing a grand challenge to robust IC design. Variations in CMOS are often divided into two types: intrinsic variations and process-induced variations. Intrinsic variations are limited by fundamental physics. They are inherent to CMOS structure, considered as one of the ultimate barriers to the continual scaling of CMOS devices. In this work the three primary intrinsic variations sources are studied, including random dopant fluctuation (RDF), line-edge roughness (LER) and oxide thickness fluctuation (OTF). The research is focused on the modeling and simulation of those variations and their scaling trends. Besides the three variations, a time dependent variation source, Random Telegraph Noise (RTN) is also studied. Different from the other three variations, RTN does not contribute much to the total variation amount, but aggregate the worst case of Vth variations in CMOS. In this work a TCAD based simulation study on RTN is presented, and a new SPICE based simulation method for RTN is proposed for time domain circuit analysis. Process-induced variations arise from the imperfection in silicon fabrication, and vary from foundries to foundries. In this work the layout dependent Vth shift due to Rapid-Thermal Annealing (RTA) are investigated. In this work, we develop joint thermal/TCAD simulation and compact modeling tools to analyze performance variability under various layout pattern densities and RTA conditions. Moreover, we propose a suite of compact models that bridge the underlying RTA process with device parameter change for efficient design optimization. / Dissertation/Thesis / Ph.D. Electrical Engineering 2011

Contact between rough surfaces occurs in numerous engineering systems and in many instances influences the macro behavior of the system. In many instances, the interaction between rough surfaces, affect the macro behavior of the system. Effective treatment of systems containing rough surface contact requires multiscale modeling and analysis approach. It is the goal of this research to develop simple methods for treating contact of rough surfaces so as to facilitate multiscale analysis of systems containing rough surface contact and friction. This dissertation considers a multi-scale approach that includes interaction at nano-scale, micron-scale and accounting for their cumulative effect as to what we normally perceive to be the influence of contact surfaces and friction. In linking each scale to a higher scale this study employs statistical means to obtain cumulative effect of smaller-scale features. A mixed interactive/optimization technique is used to derive, in approximate closed form, equations for the contact load and real area of contact dependence on approach and parameters of rough surfaces. The equations so derived relate the normal and tangential components of contact load to displacement and surface parameters for three types of contact. The nature of contact interaction that include elastic, elastic-plastic, visco-elastic, and visco-elasto-adhesive behavior are considered and equations relating the normal and tangential contact load to approach and relative sliding are obtained in approximate closed form. The approximate equations provide a tool for efficient calculation of contact force components, especially in surface optimization efforts where repetitive calculation of contact force components may be needed. The approximate equations also facilitate a multi-scale dynamic analysis wherein the effect of contact interaction can be readily included in a mechanical system model. Several dynamical problems involving mechanical systems with friction contact are presented and nonlinear dynamic analyses are employed to link the micron-scale properties of surface to the macro-scale properties of the mechanical system. These lead to, perhaps, the first derivation of contact frequency and damping in rough surface contact.

PURPOSE: To determine the potential discoloration of provisional materials by exposure to beverages and evaluate the efficacy of simulated tooth-brushing on stain removal and the effect on surface roughness. METHODS: Materials included: Jet Set-4 (Lang), Protemp Plus (3M ESPE), Luxatemp (DMG), Artbloc (Merz), Telio-CAD (Ivoclar), and Vita-CAD (Vita). Specimens (n=10/group) were immersed in: distilled water, coffee, red wine, tea, coke and cranberry juice. Color measurements were taken (Xritei5 spectrophotometer) at: baseline, 24 hours, 4 and 8 weeks. Specimens in coffee and red wine for 8 weeks were exposed to tooth-brushing for three minutes and color measurements were taken subsequently. Color differences (ΔE) after treatments were calculated using one-way ANOVA, MANOVA and post hoc Tukey test. Another group of specimens (n=10/group) were exposed to tooth-brushing under a 1.91N load using toothpaste slurry (Crest® Cavity Protection) for 20,000 cycles in two modes: soft and medium bristles (both Oral B Indicator®). Surface roughness was measured using a Mitutoyo SJ201 profilometer before and after brushing. Surface roughness Ra values were compared using one-way ANOVA and post hoc Tukey test. RESULTS: Coke and water had no significant discoloration effect (p>0.05). Red wine and coffee exhibited the highest discoloration effect. CAD-CAM blocks showed significantly lower color change, at all durations, and after brushing (p<0.001). Tooth-brushing had a significant effect (Ra) on Telio-CAD, Artbloc, Jet Set-4 and Vita-CAD. Protemp-Plus and Luxatemp groups showed no significant difference. CONCLUSIONS: Traditional materials showed less color stability when compared to CAD/CAM blocks. Tooth-brushing effect varies depending on bristle and material type.

No description available.

Surface roughness is an important parameter in the automotive Industry. This thesis is a study conducted in collaboration with QSO Interferometer systems AB (QSAB), Halmstad. The study is focused on the existing surface roughness parameters used in the automotive industry and the relationship to the CWS parameters of QISAB. The study also investigates the scope of CWS instrument developed by QISAB as a next-generation automated surface testing inline instrument. The initial study which has been conducted had 5 stages, those are the history of roughness measurement, the basic CWS parameters, the currently used surface testing instruments in the automobile industry, the use of surface metrology in the manufacturing industry and the basic principle and theory of the CWS. As the final stage to achieve the aim of the thesis a quantitative study has been conducted to compare the existing parameters with CWS parameters. The three type of comparison were done on a test piece having different range of surface roughness after different stages of grinding. These three comparisons that had been done were CWS v/s White light interferometer v/s visual inspection. The results from those quantitative analysis did support the results from the qualitative analysis.

Submitted by Suelen Reis (suziy.ellen@gmail.com) on 2013-05-08T16:09:26Z No. of bitstreams: 1 Maria Caroline_dissertacao.pdf: 3000863 bytes, checksum: 39550ba0de49ddaa7a9d9df1eda48983 (MD5) / Rejected by Alda Lima da Silva(sivalda@ufba.br), reason: Documento de Física on 2013-05-08T18:28:33Z (GMT) / Submitted by Suelen Reis (suziy.ellen@gmail.com) on 2013-05-09T16:49:27Z No. of bitstreams: 1 Maria Caroline_dissertacao.pdf: 3000863 bytes, checksum: 39550ba0de49ddaa7a9d9df1eda48983 (MD5) / Approved for entry into archive by Rodrigo Meirelles(rodrigomei@ufba.br) on 2013-05-09T17:10:10Z (GMT) No. of bitstreams: 1 Maria Caroline_dissertacao.pdf: 3000863 bytes, checksum: 39550ba0de49ddaa7a9d9df1eda48983 (MD5) / Made available in DSpace on 2013-05-09T17:10:10Z (GMT). No. of bitstreams: 1 Maria Caroline_dissertacao.pdf: 3000863 bytes, checksum: 39550ba0de49ddaa7a9d9df1eda48983 (MD5) Previous issue date: 2009 / Nos últimos anos, buscando melhorar os diagnósticos em imagens biomédicas, foram desenvolvidos diversos métodos de filtragem das imagens de forma a facilitar a detecção de padrões estruturais associados aos tumores. Por outro lado, a geometria fractal pode ser aplicada para descrever a hierarquia das irregularidades dos fenômenos naturais. As propriedades de um fractal podem ser caracterizadas por um conjunto de expoentes que descrevem um padrão no comportamento das flutuações. Esse conjunto de expoentes representa uma descrição mais completa da medida fractal e é definida como multifractal. Os parâmetros obtidos através da caracterização multifractal contêm informações que podem relacionar as propriedades observadas em diferentesescalas com os diferentes padrões de ocupação das células no tecido. Tais parâmetros oferecem, portanto, um aprofundamento na compreensão da dinâmica de formação de tais padrões. O objetivo geral desta dissertação é avaliar o formalismo multifractal como uma ferramenta útil para a caracterização de padrões espaciais de tumores hepáticos e até onde nos sabemos trata-se de um trabalho original no tema. Nele discutimos um refinamento sobre os métodos de caracterização de tumores embasados na teoria fractal de forma a considerar o espectro de dimensões fractais mediante uma análise multifractal. As imagens de tumores utilizadas foram consideradas como superfícies multi-afins. Foi feito um estudo de casos a partir de três amostras de exames médicos tomográficos com o objetivo de se testar o método na obtenção do grau de heterogeneidade das imagens. O método de cálculo do espectro multifractal foi validado de maneira a avaliar o efeito das diferentes resoluções nas imagens e os diferentes valores dos expoentes de rugosidade para o caso de superfícies monofractais. As características multifractais foram analisadas por duas abordagens. Primeiro em relação às imagens lesadas pelo tumor e segundo, pela comparação desses resultados com as imagens não atingidas pela lesão. Com esta análise pôde-se verificar que nos casos analisados as imagens apresentam um comportamento multifractal, o que indica um padrão de heterogeneidade maior do que se supunham os métodos fractais. / Salvador

Diversas substâncias químicas têm sido utilizadas no processo de desinfecção e higiene de dispositivos de resina acrílica, no entanto, muitas destas substâncias são utilizadas de forma empírica. Sendo assim, o objetivo do presente estudo foi avaliar a influência da imersão em vinagre, hipoclorito de sódio e peróxido de hidrogênio na rugosidade e na dureza de uma resina acrílica de termoativação Meliodent® Heat Cure (Heraeus Kultzer, Alemanha). Foram confeccionados 130 corpos de prova de resina acrílica e estes foram aleatoriamente divididos em 13 grupos (n=10). O grupo controle permaneceu a seco, sem imersão. Os grupos teste foram submetidos à imersão em vinagre, hipoclorito de sódio 1%, peróxido de hidrogênio 10V e água destilada por diferentes tempos (30h, 150h ou 300h). As soluções foram protegidas da luz e trocadas a cada período de 24 horas. Após o período de imersão foram avaliadas a microdureza Knoop e a rugosidade Ra da resina acrílica. A microdureza Knoop dos corpos foi obtida com o microdurômetro automático HMV-2 (Shimadzu, Japão) sendo utilizada a medida de cinco mensurações em cada corpo de prova com uma carga de 25g por 10 segundos. A rugosidade Ra foi determinada pela media de cinco leituras realizadas em cada corpo de prova, utilizando-se um Rugosímetro SJ-201 (Mitutoyo, Japão). Os resultados mostraram que houve diferença estatisticamente significativa na microdureza da resina acrílica de termopolimerização após a imersão durante 30h, 150h e 300 h em vinagre, hipoclorito de sódio 1%, peróxido de hidrogênio 10V e água destilada, quando comparado com o grupo controle, que permaneceu a seco. Os resultados da rugosidade não mostraram diferença estatisticamente significativa após a imersão durante 30h, 150h e 300h em vinagre e água destilada quando comparados com o grupo controle, sem imersão. Com base no desenho experimental e nos resultados do presente estudo é possível concluir que o vinagre pode se tornar uma opção para desinfecção caseira de dispositivos de resina acrílica. / Several substances have been used for the disinfection and hygiene of acrylic resin devices, however, many of these substances are used empirically. Thus, the aim of this study was to evaluate the influence of immersion in vinegar, sodium hypochlorite and hydrogen peroxide on the surface roughness and hardness of thermo-cured acrylic resin Meliodent® Heat Cure (Heraeus Kultzer, Germany). 130 specimens of acrylic resin were produced and randomly divided into 13 groups (n = 10). The control group remained dry without immersion. The test groups were immersed in vinegar, 1% sodium hypochlorite, hydrogen peroxide 10V and distilled water during different times (30h, 150h and 300h). The solutions were protected from light and changed every 24 hours. After the immersion period, Knoop hardness and surface roughness of the acrylic resin were evaluated. The Knoop hardness of the specimens were obtained through an automatic microhardness tester HMV-2 (Shimadzu, Japan) with five measurements on each specimen with a load of 25g for 10 seconds. The roughness was determined by five readings on each specimen using a Surface Roughness Tester SJ-201 (Mitutoyo, Japan). The results showed a statistically significant difference in microhardness after immersion for 30h, 150h and 300h in vinegar, 1% sodium hypochlorite, hydrogen peroxide and distilled water 10V, compared with the control group. The results of roughness showed no statistically significant difference after immersion for 30h, 150h and 300h in vinegar and distilled water when compared with the control group. Based on the experimental design and results of this study it can be concluded that vinegar can eventually become an option for homemade disinfecting apparatus of acrylic resin.

Submitted by Sueli Souza Leite null (leitess@bol.com.br) on 2016-04-12T20:03:45Z No. of bitstreams: 1 1000.pdf: 2835888 bytes, checksum: 43aa2f9aeb4c2f1b54f42d927c0da040 (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-04-15T14:06:36Z (GMT) No. of bitstreams: 1 leite_ss_me_bauru.pdf: 2835888 bytes, checksum: 43aa2f9aeb4c2f1b54f42d927c0da040 (MD5) / Made available in DSpace on 2016-04-15T14:06:36Z (GMT). No. of bitstreams: 1 leite_ss_me_bauru.pdf: 2835888 bytes, checksum: 43aa2f9aeb4c2f1b54f42d927c0da040 (MD5) Previous issue date: 2016-02-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O lixamento da madeira envolve inúmeras variáveis as quais influenciam na qualidade superficial da peça produzida, tornando-se por isso, um processo complexo. Atua de forma imprescindível nas indústrias, principalmente fabricantes de móveis, painéis, molduras, esquadrias e dentre outras. Entretanto, é tratado de forma empírica, prejudicando a qualidade do produto e elevando os custos de produção, visto que é, um dos processamentos mais caros na indústria de madeira. Sabido disto, este trabalho, teve por objetivo combinar um conjunto de fatores para padronizar o processo de lixamento. Para isto, seguiu o planejamento experimental de Taguchi, método baseado em conceitos estatísticos, responsável por diagnosticar o conjunto de fatores que propiciam o alcance da qualidade do produto final. A experimentação realizou-se em relação a uma matriz ortogonal L8, criando assim, oito condições diferentes de lixamento, repetindo-as três vezes cada, totalizando em 24 ensaios. Variou os níveis dos seguintes fatores: granulometria, grão abrasivo, sentido do lixamento e espécie da madeira, com o intuito de analisar o comportamento dos parâmetros: emissão sonora, potência, rugosidade, taxa de remoção e temperatura no decorrer do processo. Por meio da análise de variância (ANOVA), concluiu-se que o comportamento dos parâmetros foram influênciados pelos fatores estipulados, os quais interferiram na qualidade superficial da madeira. / The sanding of wood involves numerous variables which influence the surface quality of the produced piece, becoming therefore a complex process. It is a crucial process in industries, particularly manufacturers such as furniture, panels, moldings, frames and others. However, the process is trated empirically, decreasing the product quality and increasing production costs, since it is one of the most expensive processes in the wood industry. According to this, this paper, aimed to standardize a set of factors to achieve the best surface finish of the wood. For this, the following experimental design Taguchi method based on statistical concepts, responsible for diagnosing the set of factors that promote the achievement of the quality of the final product. The experiment was performed in relation to a matrix L8 orthogonal matrix, creating eight different conditions sanding, repeating three times each, totaling in 24 trials. Varied levels of the following factors: particle size, abrasive grain, sense of sanding and timber species, in order to analyze the parameters of behavior, noise emission, power, roughness, temperature and removal rate in the process. Through analysis of variance (ANOVA), it was concluded that the behavior parameters were influenced by prescribed factors which interfere in the surface quality of the wood.