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Computer-aided design and manufacturing of tactile mapsChan, Chi-fung, 陳智鋒 January 2007 (has links)
published_or_final_version / abstract / Mechanical Engineering / Master / Master of Philosophy
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Incorporating GIS and CAD technologies in the modelling of three-dimensional urban landscape of Hong KongHo, Lee-kin, Joe., 何利堅. January 1999 (has links)
published_or_final_version / Geography and Geology / Master / Master of Philosophy
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Improving fit through the integration of anthropometric data into a computer aided design and manufacture based design processWilliams, Gavin L. January 2007 (has links)
For all types of clothing and body worn technologies it is important to consider how they integrate and interact with the complex shapes that form the unique profile of the human body. This interaction determines the fit of these products and it is often difficult to generate a fit that can simultaneously accommodate these complex shapes. Achieving the correct fit is determined by a number of different factors that must be combined appropriately to create the fit associated with a particular product. This is particularly applicable to Personal Protective Equipment (PPE) to ensure it provides protection while maintaining comfort, mobility and good interaction with the surrounding environment. Integrating suitable anthropometric data into the design and manufacture of this type of clothing plays a critical role in achieving a good fit. By using various processes of Computer Aided Design (CAD) and Computer Aided Manufacture (CAM), the detail contained within these data can be quickly and accurately transferred into physical tools. The aim of this study was to demonstrate and validate a method of enhancing the fit of PPE handwear. This has been achieved through an action research strategy using descriptive and practical research methods. The research tools primarily used are case studies, used to demonstrate how manually collected 2D anthropometric data can be used to generate computer models that represent these data in a 3D form. The products of the case studies are tools that have been introduced into the design and manufacture processes of commercial handwear manufacturing environments. The tools have successfully been used to produce gloves using two different manufacturing methods and been assessed to analyse their fit. An improvement in fit for the gloves has been quantified through user trials to determine the level of increased performance afforded to the wearer. The conclusions drawn from the case studies demonstrate that the integration of anthropometric data and CAD/CAM can greatly influence the fit of handwear and improve the iterative processes of its design. However, the data alone does not achieve this as the added integration of tacit knowledge related to glove design is needed to ensure the correct properties are included to the meet the needs of the target population. The methods developed in the case studies have the potential to be applied to other products where fit and interaction with the human body are important design considerations.
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Caracterização de blocos sinterizados à base de CoCrMo visando a obtenção de próteses odontológicas por fresagem CAD/CAM / Characterization of Co-Cr-Mo sintered blocks in order to obtain dental prostheses by prototyping CAD/CAMFreitas, Bruno Xavier de 19 December 2016 (has links)
Estudou-se a caracterização de blocos sinterizados à base de Co-Cr-Mo visando a obtenção de próteses odontológicas por fresagem CAD/CAM. O processo de sinterização foi estudado e ocorreu através do transporte difusional de massa e calor no estado sólido, denominado sinterização no estado sólido. Esse fenômeno produz uma forte união entre as partículas devido ao transporte de massa, em escala atômica, sob condições controladas de tempo, temperatura e atmosfera. Foram realizadas sinterizações interrompidas a 800, 1000, 1200 e 1300°C nos tempos de 15 minutos, 1 hora e 4 horas. A liga foi caracterizada nas condições recebida e sinterizadas em termos de composição química, propriedades mecânicas e caracterização microestrutural. Para isto, utilizou-se fluorescência de raios X, dilatometria, ensaios de Arquimedes, ensaios de dureza, ensaios de compressão, microscopia eletrônica de varredura (MEV), microscopia óptica e microanálise eletrônica dispersiva (EDS). Os resultados composicionais indicam que a liga se encontrava dentro da faixa de composição química estabelecida pelo manual do fabricante e pela norma ASTM 1537. As partículas analisadas na condição pré-sinterizada exibiram formato esférico, indicando uma provável utilização de pós atomizados. A estimativa do levantamento da distribuição do tamanho das partículas foi realizado utilizando o programa de computador ImageJ, e a distribuição foi caracterizada como assimétrica positiva. O material no estado recebido se apresentou monofásico. A fase presente encontrada foi ?Co com estrutura cristalina CFC. Em contrapartida, as amostras sinterizadas apresentaram porções de fase ?Co, com estrutura cristalina hexagonal, fase esta formada a partir da transformação ?Co <-> ?Co, na qual, a energia armazenada na forma de defeitos é a força motriz da transformação. E sugere que a transformação ocorreu durante resfriamento. A amostra sinterizada por quatro horas em 1200°C apresentou-se no estágio final de sinterização, dado que os poros encontrados tinham aspecto arredondado e com densificação maior que 90%. Os resultados de compressão indicam tensão média de ruptura de 2523 ± 168 MPa. / This work studied the characterization of Co-Cr-Mo sintered blocks in order to obtain dental prosthesis by prototyping CAD/CAM. The sintering process was studied through diffusional mass transport in solid state, termed solid state sintering. This phenomenon produces a strong bond between the particles due to mass transport, at the atomic scale, under controlled conditions of time, temperature and atmosphere. The interrupted sintering was performed at 800, 1000, 1200 and 1300 ° C in times to 15 minutes, 1 hour and 4 hours. The alloy was characterized in conditions as received and sintered in terms of chemical composition, mechanical properties and microstructural characterization. For this, we used X-ray fluorescence, dilatometry, Archimedes tests, hardness tests, compression tests, scanning electron microscopy (SEM), optical microscopy and dispersive electron microanalysis (EDS). The results indicate that the alloy was within the chemical composition range established by the manufacturer and ASTM 1537. The particles analyzed in the pre-sintered condition showed spherical shape, indicating a likely use of atomized powders. The estimate of the particle size distribution was performed using ImageJ software, and the distribution is characterized as positive asymmetric. The samples in the received state were monophasic. This phase was found ?Co with FCC crystal structure. On the order hand, the sintered samples showed ?Co phase portions with hexagonal crystal structure, phase formed from the transformation ?Co <-> ?Co, in which the energy stored in the form of defects is the driving force of transformation and suggests that transformation occurred during the cooling. Sample sintered during four hours at 1200°C was in the final stages of sintering, since the pores were found aspect rounded and densification above 90%. The compression results indicate rupture stress at 2523 ± 168 MPa.
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Effect of CAD/CAM abutment height and cement type on the retention of zirconia crowns / Efeito da altura do pilar CAD / CAM e tipo de cimento na retenção de coroas de zircôniaSilva, Camila Perfeito Evangelista da 07 May 2018 (has links)
Aim: To evaluate the effect of different Ti-base abutment heights and cement type on the pullout retention of zirconia-based restorations. Methods: Identical crowns were designed in a CAD software to fit two different Tibase abutment heights, as follows (n=10/group): (i) 4-mm-height Ti-base abutment (Tall), and (ii) 2.5-mm-height Ti-base abutment (Short). Four cement types were selected: (i) Temporary cement (Provisional); (ii) Glass-ionomer cement (Meron); (iii) self-adhesive resin cement (U200), and (iv) conventional resin cement (Ultimate) with universal adhesive for treatment of titanium and zirconia substrates. Pull-out testing was performed in a universal testing machine. Data were statistically evaluated through two-way analysis of variance following post-hoc comparisons by Tukey test. Results: Tall Ti-base abutments demonstrated similar retention to short abutments when data is collapsed over cement (p>0.74). Data evaluation as a function of cement type demonstrated the superiority of resin-based cements relative to provisional and glass-ionomer groups (p<0.01). Retentiveness data as a function of both factors demonstrated similar force to dislodgment between tall and short abutments for all within cement comparisons (p>0.42), except for U200 (p=0.032). Also, tall abutments cemented with Ultimate evidenced higher pull out values than U200 (p=0.043), and both were significantly more retentive than tall provisional and meron (p<0.001). No significant difference was observed between U200 and Ultimate cements for short abutments (p=0.758), and both presented statistically higher pullout values than provisional and glass-ionomer (p=0.001). Conclusions: While Ti-base abutment height have not influenced zirconia superstructure retentiveness, resin-based cements significantly evidenced higher retention than glass ionomer and temporary cements. / Objetivo: Avaliar o efeito de diferentes alturas de interface de Titânio (Ti) e diferentes tipos de cimento na retenção de coroas de zircônia. Métodos: Coroas idênticas foram projetadas em um software de CAD capaz de adaptar duas alturas diferentes do pilar de interface de Ti: cada grupo foi composto de 10 amostras conforme se segue: (i) interface de Ti de 4 mm de altura (alto) e (ii) interface de 2,5 mm de altura (curto). Foram selecionados quatro tipos de cimento: (i) cimento temporário (Provisional); (ii) Cimento de ionômero de vidro (Meron); (iii) cimento resinoso auto-adesivo (U200) e (iv) cimento resinoso convencional (Ultimate) com adesivo universal para tratamento de substratos de titânio e zircônia. O teste de tração foi realizado em uma máquina de ensaio universal. Os dados foram avaliados estatisticamente através de análise de variância a dois critérios, após comparações pós-hoc pelo teste de Tukey. Resultados: As interfaces de Ti demonstraram retenção semelhante aos pilares curtos quando os dados foram colapsados sobre o cimento (p> 0,74). A avaliação dos dados em função do tipo de cimento demonstrou a superioridade dos cimentos à base de resina em relação aos grupos de cimentos temporário e de ionômero de vidro (p <0,01). Os dados de retenção em função de ambos os fatores demonstraram força semelhante ao deslocamento, entre pilares altos e curtos, para todos dentro das comparações de cimento (p> 0,42), exceto para U200 (p = 0,032). Além disso, os pilares altos cimentados com Ultimate evidenciaram maiores valores de tração do que os cimentados com U200 (p = 0,043), e ambos foram significativamente mais retentivos do que o pilar alto cimentado com cimento Provisional e o Meron (p <0,001). Não foi observada diferença significativa entre os cimentos U200 e Ultimate para pilares curtos (p = 0,758) e ambos apresentaram valores de tração estatisticamente mais elevados que os cimentos de ionômero de vidro e cimento temporário (p = 0,001). Conclusões: Embora a altura da interface de Ti não tenha influenciado a retenção das coroas de zircônia, os cimentos resinosos resultaram em maior retenção do que o ionômero de vidro e cimentos temporários.
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The capability and accuracy of the CEREC CAD/CAM system to fabricate custom posts by direct scanning of simulated canal blocks in vitroBahabri, Rayan 28 September 2016 (has links)
Dentists have been using CAD/CAM technology to fabricate custom posts and cores. However, most of these cases used impression material as a way to indirectly scan the canal. The aim of this study was to evaluate the capability of CEREC CAM/CAM machine to directly scan simulated canal blocks without an impression and which of the following factors affected the accuracy of fit; taper, length and tip diameter. Material and methods: 32 epoxy resin blocks with post space simulator were made from metal post templates to resemble post space preparations. Three factors were considered in-group variations; length of the post, taper and diameter of the post’s tip. Eight groups of four specimens each were milled from acrylic blocks using the CEREC CAD/CAM system and one extra group of one specimen each was for cast post fabrication. Group A (Length = 8mm, taper = 4o, tip diameter = 0.8mm), Group B (Length = 8mm, taper = 4o, tip diameter = 1 mm), Grope C (Length = 8mm, taper = 6o, tip diameter = 0.8mm), Group D (Length = 8mm, taper = 6o, tip diameter = 1 mm), Group E (Length = 10 mm, taper = 4o, tip diameter = 0.8mm), Group F (Length = 10 mm, taper = 4o, tip diameter = 1 mm), Grope G (Length = 10mm, taper = 6o, tip diameter = 0.8mm), Group H (Length = 10mm, taper = 6o, tip diameter = 1mm). Each block, with its cemented post was sectioned in a coronal-apical direction. An image was recorded for each slice. Cement thicknesses were measured in four areas. The results showed that group E and D have the smallest cement thickness with 84 and 89 microns respectively. Both groups shared a tip diameter of 1mm. This result is within the clinically acceptable limit of the cement layer around the posts and is comparable to the cast group in our study. Tip diameter and length significantly affected the cement thickness in an inverse relationship.
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Modelo superficie-trayectoria: un modelo geométrico para el diseño y la fabricación de objetos tridimensionalesMolina-Carmona, Rafael 29 July 2002 (has links)
No description available.
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Utiliza??o do laser de diodo como alternativa no tratamento de superf?cie em restaura??es CAD/CAMBettinelli, Juliana Doncatto 10 January 2017 (has links)
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Previous issue date: 2017-01-10 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Since the 1970s, the application of the CAD / CAM technique has been suggested in the dental clinic with the aim of simplifying, automating and guaranteeing quality levels with micrometric adaptations of our dental prostheses4,5. The objective of this study was to evaluate the viability of the diode laser as an alternative to hydrofluoric acid and aluminum oxide blasting compared to the machining process in the surface treatment of the following restorative materials: hybrid ceramics, nanoceramic resin, reinforced lithium silicate ceramics by zirconia, feldspathic ceramics, vitreous ceramics with crystalline structure of lithium disilicate, vitreous ceramics with crystalline structure of leucite. A specimen was prepared for each of the seven CAD / CAM restorative materials; And, this was divided into four parts. The dimensions of the specimens were 1cm in length and 1cm in width, in the thickness of 1mm, color A2. The surface area of the specimen was subdivided into quadrants; (A) was applied to the diode laser, (B) received the blasting of aluminum oxide, (C) received the application of hydrofluoric acid (5 or 10%) or cleaning with isopropyl alcohol (10%); As indicated by the manufacturer, (D) no conditioning was applied and the
surface passed through the machining process only. Images were taken at a 15,000- fold increase (SEM). For the surface roughness test, ten measurements were taken, with cut-off 0.25. Statistical data were submitted to ANOVA and Tukey's test. Knowing the need to seek new alternatives of a conditioning protocol on the surface of restorative materials in CAD / CAM, it was highly effective, fast, simplified and mainly safe. It can be stated that the use of the diode laser seems to be feasible for the surface treatment of ceramic with crystalline structure of lecithin Empress CAD and ceramic feldspathic Cerec Blocs CAD / CAM, as it produced changes in the surface of these ceramics studied. / Desde a d?cada de setenta, a aplica??o da t?cnica CAD/CAM vem sendo sugerida na cl?nica odontol?gica com o objetivo de simplificar, automatizar e garantir n?veis de qualidade com adapta??es microm?tricas das nossas pr?teses dent?rias4,5. O objetivo deste estudo foi avaliar a viabilidade do laser de diodo, como alternativa ao ?cido fluor?drico e jateamento com ?xido de alum?nio em compara??o ao processo de usinagem no tratamento superficial dos seguintes materiais restauradores: cer?mica h?brida, resina nanocer?mica, cer?mica de silicato de l?tio refor?ada por zirc?nia, cer?mica feldsp?tica, cer?mica v?trea com estrutura cristalina de dissilicato de l?tio, cer?mica v?trea com estrutura cristalina de leucita. Foi confeccionado um corpo de prova para cada um dos sete materiais restauradores em CAD/CAM; e, este foi dividido em quatro partes. As dimens?es dos corpos de prova foram de 1 cm de comprimento por 1cm de largura, na espessura de 1mm, cor A2. A ?rea de superf?cie do corpo-de-prova foi subdivida em quadrantes; de forma que em (A) foi aplicado o laser de diodo, (B) recebeu o jateamento de ?xido de alum?nio, (C) recebeu a aplica??o de ?cido fluor?drico (5 ou 10%) ou limpeza com ?lcool isoprop?lico (10%); conforme indica??o do fabricante, (D) n?o foi aplicado condicionamento e a superf?cie passou apenas pelo processo de usinagem. Foram realizadas imagens no aumento de 15.000 vezes (MEV). Para o teste de rugosidade
superficial, foram tomadas dez medidas, com cut-off (valor de corte) 0,25. Os dados estat?sticos obtidos foram submetidos ? ANOVA e ao teste de Tukey. Sabendo-se da necessidade de buscar novas alternativas de um protocolo de condicionamento na superf?cie dos materiais restauradores em CAD/CAM, que fosse altamente eficaz, r?pido, simplificado e principalmente seguro. Pode-se afirmar que a utiliza??o do laser de diodo parece ser vi?vel para o tratamento superficial da cer?mica v?trea com estrutura cristalina de leucita Empress CAD e cer?mica feldsp?tica Cerec Blocs CAD/CAM, pois produziu altera??es na superf?cie destas cer?micas estudadas.
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Restaura??es endocrown produzidas em CAD/CAM : ensaio de carga m?xima de fratura e an?lise do padr?o de falhaOliveira, P?mella Tomazi Godoy de 25 January 2018 (has links)
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Previous issue date: 2018-01-25 / Conselho Nacional de Pesquisa e Desenvolvimento Cient?fico e Tecnol?gico - CNPq / Aims: to evaluate in vitro the fracture strength and failure pattern of endocrown restorations performed with Incoris TZI ceramics, Celta Duo and Empress CAD cemented on endodontically treated molars. Materials and methods: forty extracted sound molars were randomly distributed into 4 groups (n = 10). After being endodontically treated, they were restored with endocrowns carried out through the CEREC system with three different materials: Empress CAD (Ivoclar Vivadent), Celta Duo (Dentsply/Sirona) or Incoris TZI (Dentsply/Sirona). After, they were subjected to mechanical fatigue testing with vertical load application of 200N, totalling 500,000 cycles. Subsequently, the samples were submitted to the maximum fracture load under compressive force on the long axis of the tooth at cross-head speed of 1mm/min.. After the fracture strength testing the fracture patterns were evaluated being classified as repairable (cusps) or irreparable (pulp chamber floor rupture).
Results: Sound: 4306Na ? 716.5; Incoris TZI: 3770NAb ? 846; Empress CAD: 1994Nc ? 498.5; Celta Duo: 3298Nb ? 1121. The Incoris TZI and Celta Duo presented the same proportion of irreparable fractures, 60%. The Empress Cad presented the same proportion for the repairable and irreparable fractures (50%). Conclusion: The Incoris TZI presented higher fracture strength, followed by Celta Duo, but did not differ statistically. In turn, the Empress CAD differed statistically from the others presenting lower fracture strength. The Incoris TZI and Celta Duo presented the same prognosis of failures with predominance of irreparable failures. / Objetivos: avaliar in vitro a resist?ncia ? fratura e o padr?o de falha de restaura??es endocrown realizadas com as cer?micas inCoris TZI, Celtra Duo e Empress CAD cimentadas sobre molares tratados endodonticamente. Materiais e m?todos: quarenta dentes molares h?gidos extra?dos foram distribu?dos aleatoriamente em 4 grupos (n=10). Ap?s serem endodonticamente tratados, foram restaurados com endocrowns realizadas atrav?s do sistema CEREC/InLab (Sirona) com tr?s diferentes materiais: Empress CAD (Ivoclar Vivadent), Celtra Duo (Dentsply/Sirona) ou inCoris TZI (Dentsply/Sirona). Ap?s, foram submetidos ? fadiga mec?nica com aplica??o de carga vertical de 200N, totalizando 500.000 ciclos. Posteriormente, foi testada a carga m?xima de fratura com for?a compressiva no longo eixo do dente sob velocidade de 1mm/min.. Ap?s o ensaio foram avaliados os padr?es de fratura e classificados em repar?veis (c?spides) ou irrepar?veis (assoalho da c?mara pulpar).
Resultados: H?gidos: 4306Na ? 716,5; inCoris TZI: 3770Nab ? 846; Empress CAD:1994Nc ? 498,5; Celtra Duo: 3298Nb ? 1121. O grupo inCoris TZI e Celtra Duo apresentaram a mesma propor??o de fraturas irrepar?veis, 60%. O grupo Empress Cad apresentou a mesma propor??o para as fraturas repar?veis e irrepar?veis (50%). Conclus?o: O grupo inCoris TZI apresentou maior resist?ncia ? fratura, seguido do grupo Celtra Duo, mas n?o diferiram estatisticamente. Por sua vez, a cer?mica Empress CAD diferiu estatisticamente das demais apresentando menor valor de resist?ncia ? fratura. O grupo Incoris TZI e Celtra Duo apresentaram o mesmo progn?stico de falhas com predomin?ncia de falhas irrepar?veis.
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Avalia??o da libera??o de bisfenol A em blocos de materiais dent?rios para CAD/CAMCarvalho, Ligia Maria Nogarett Pibernat de 25 April 2017 (has links)
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Previous issue date: 2017-04-25 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The aim of the present study was to asses the present of Bisphenol A in dental material used on CAD/CAM block.For this In Vitro study, blocks for CAD-CAM, Lava Ultimate, Enamic and Mark II in standardized fragments containeing Bisphenol A were evaluated. Ten fragments of each block were made: n = 30, immersed in deionized water on group 1 and artificial saliva Kin Hidrat on group 2 in a light protected bottle.Stored in a culture stove for 24 hours, all samples were put in 1,5ml bottles containing 1,0ml of artificial saliva (KIN HIDRAT, PharmaKIN, S?o Paulo, Brazil ) on group 1 and deionized water on group 2, and then freezed in -80?C for 24 hours. After the 24 hour period, the samples were submitted to High Efficiency Chromatography on Toxicology and Pharmacology Institute of PUCRS as
methodology described on this study.After cromatographic analysis of groups 1 and
2, the non-release of Bisphenol A was observed in all groups of samples tested. All
groups and samples presented peak release of unidentified substance of different
molecular weight and different breaking time than the Bisphenol A standard.
Additional researches using other analysis methods are needed to examine the
cumulative estrogenic effects of Bisphenol A dental materials for CAD CAM and
composite resins. / O objetivo geral deste estudo foi avaliar o componente Bisfenol A presente em blocos de materiais dent?rios utilizados no sistema CAD/CAM quanto a libera??o ou n?o de Bisfenol A. Foram avaliados para a realiza??o deste estudo in vitro, blocos para CAD/CAM, Lava Ultimate, Enamic e Mark II, em fragmentos padronizados, cuja matriz de resina composta continha Bisfenol A. Foram confeccionados 10 fragmentos de cada um dos blocos: n = 30, imerso em ?gua deionizada no grupo 1 e saliva artificial KinHidrat no grupo 2 em frasco protegido da luz. Armazenadas em estufa por 24hs,todas as amostras, ap?s o periodo de 24hs, foram armazenadas em recipientes de 1,5ml contendo 1,0 ml de saliva artificial (KIN HIDRAT,PharmaKIN,
S?o Paulo, Brasil ) no grupo 1 e ?gua deionizada no grupo 2 e ap?s congeladas ? - 80?C por 24hs. Decorrido o per?odo de 24h, as amostras foram submetidas a cromatografia de alta efici?ncia (HPLC) no Instituto de Toxicologia e Farmacologia da PUCRS com metodologia descrita no estudo.Ap?s an?lise cromatogr?fica dos
grupos 1 e 2 observou- se a n?o libera??o de Bisfenol A em nenhum dos grupos de amostras testadas.Todos os grupos e amostras apresentaram pico de libera??o de subst?ncia n?o identificada de diferente peso molecular e diferente tempo de quebra do padr?o de Bisfenol A. Pesquisas adicionais, empregando outros m?todos de an?lise s?o necess?rias para examinar os efeitos estrog?nicos cumulativos do Bisfenol A de materiais dent?rios para CAD/CAM e resinas compostas.
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