Submitted by Caroline Xavier (caroline.xavier@pucrs.br) on 2017-05-23T17:30:49Z No. of bitstreams: 1 DIS_MAURICIO_TOMAZONI_PEIXOTO_COMPLETO.pdf: 977170 bytes, checksum: 550fe78287feca797929ac42cf3a7c9c (MD5) / Made available in DSpace on 2017-05-23T17:30:49Z (GMT). No. of bitstreams: 1 DIS_MAURICIO_TOMAZONI_PEIXOTO_COMPLETO.pdf: 977170 bytes, checksum: 550fe78287feca797929ac42cf3a7c9c (MD5) Previous issue date: 2016-12-13 / Conselho Nacional de Pesquisa e Desenvolvimento Cient?fico e Tecnol?gico - CNPq / The increasing demand for aesthetic restorations, associated with the evolution of techniques and materials, allowed the preparation of prosthetic pieces of reduced thickness. The introduction of CAD / CAM technology has made accurate and fast restorations. However, the final color of the restoration remains the direct responsibility of the dentist, where a visual assessment of color can cause errors, while an instrumental color measurement has accurate readings. The objective of the study was to investigate the factors that may influence the final color and translucency of different veneers with different thicknesses made by CAD/CAM materials and different types of resin cements on a darkened substrate. The samples were made by copy biogeneric in the CEREC SW 4.2 system, after a sample calculation of the pilot project, 60 upper central incisors of the right side of color C3 of epoxy resin were selected in 12 groups of 5 elements, divided according to type of (Lava Ultimate HT and LT), facet thickness (0.3mm / 0.6mm / 1.0mm) and cement type (Relyx Ultimate and Relyx Veneer). After cementation, the samples were taken with the spectrophotometer at a value of ?E in 6 different times with a silicone guide on the tooth, which ensures that the color is uniform. The results showed a significant difference in the values of ?E in groups 1 and 4 (HT and LT of 0.3 mm) cemented with Relyx Ultimate, in groups 7 and 9 (HT of 0.3 mm and 1.0 mm), and in groups 10 And 12 (LT of 0.3mm and 1.0mm) cemented with Relyx Veneer. However, the results were not significant for the masking of the darkened substrate over time, however, significant differences in ?E values were. / A crescente demanda por restaura??es est?ticas, associada a evolu??o das t?cnicas e materiais, possibilitaram a confec??o de pe?as prot?ticas de espessuras reduzidas. A introdu??o da tecnologia CAD/CAM possibilitou a realiza??o de restaura??es precisas e exatas rapidamente. No entanto, a cor final da restaura??o continua sendo responsabilidade direta do dentista, onde uma avalia??o visual de cor pode ocasionar erros, enquanto uma medi??o de cor instrumental possui leituras precisas. O objetivo do estudo foi realizar uma investiga??o dos fatores que podem influenciar a cor final e translucidez de facetas com diferentes espessuras confeccionadas por materiais CAD/CAM e diferentes tipos de cimentos resinosos sobre um substrato escurecido. As amostras foram confeccionadas por c?pia biogen?rica no sistema CEREC SW 4.2, ap?s c?lculo amostral do projeto piloto, foram selecionados 60 incisivos centrais superiores do lado direito de cor C3 de resina ep?xi foram divididos em 12 grupos de 5 elementos, divididos de acordo com tipo de material (Lava Ultimate HT e LT), espessura da faceta (0,3mm/ 0,6mm/ 1,0mm) e tipo de cimento (Relyx Ultimate e Relyx Veneer). Ap?s a cimenta??o, realizou-se a tomada de cor das amostras com o espectrofot?metro pelo valor de ?E em 6 tempos distintos com uma guia de silicone sobre o dente, que garante que a tomada de cor seja uniforme. Os resultados mostraram diferen?a significativa nos valores de ?E nos grupos 1 e 4 (HT e LT de 0,3mm) cimentados com Relyx Ultimate, nos grupos 7 e 9 (HT de 0,3mm e 1,0mm), e nos grupos 10 e 12 (LT de 0,3mm e 1,0mm) cimentados com Relyx Veneer. Entretanto os resultados n?o foram significativos quanto ao mascaramento do substrato escurecido ao longo do tempo, entretanto, foram observadas diferen?as significativas nos valores de ?E ao longo do tempo em uma an?lise intra-grupos.

Submitted by Caroline Xavier (caroline.xavier@pucrs.br) on 2017-06-26T14:49:22Z No. of bitstreams: 1 DIS_JONAS_PEREIRA_ANDRADE_PARCIAL.pdf: 141765 bytes, checksum: 99338991681873f9d3d7028d9e7cdfa9 (MD5) / Made available in DSpace on 2017-06-26T14:49:22Z (GMT). No. of bitstreams: 1 DIS_JONAS_PEREIRA_ANDRADE_PARCIAL.pdf: 141765 bytes, checksum: 99338991681873f9d3d7028d9e7cdfa9 (MD5) Previous issue date: 2017-01-19 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The aim of the study was to evaluate, in vitro, the fracture resistance of occlusal veneers, made by CAD/CAM, with Lava Ultimate, e.max CAD and Vita Enamic materials in thicknesses of 0.6 mm and 1.5 mm. Seventy third human sound molars were randomly divided into seven groups (n = 10) according to the variables material and thickness, with the sound teeth as control. The root of the teeth was embedded into a self-cured acrylic resin and the teeth were prepared to simulate advanced erosion of the occlusal surface. The occlusal veneers were made using CAD-CAM technology, being luted to the preparation with adhesive systems and resin cements. After storage in distilled water at 37 ?C for 24 h, the samples were submitted to mechanical cyclic loading (1 million cycles at 100 N load). Subsequently, the sound teeth and the samples with the occlusal veneers were submitted to the fracture resistance test in a universal testing machine with crosshead speed of 1 mm/min. The failures were classified as reparable and irreparable. According to two-way ANOVA, the interaction between material and thickness was significant (p=0.013). The highest fracture resistance was obtained for the e.max CAD in the thickness of 1.5 mm (4995 N), being statistically superior to the other groups (p <0.05). The lowest fracture resistance was obtained for Vita Enamic at 0.6 mm thickness (2973 N), not being significantly different from e.max CAD 0.6 mm (3067 N), Lava Ultimate 0.6 mm (3384 N), Vita Enamic 1.5 mm (3540 N) and Lava Ultimate 1.5 mm (3584 N) (p>0.05). According to one- way ANOVA, the fracture resistance of the sound teeth (3991 N) did not differ significantly from the teeth with occlusal veneers (p> 0.05). The failures were predominantly repairable, except for sound teeth and Lava Ultimate 1.5 mm. The Lava Ultimate, e.max CAD and Vita Enamic occlusal veneers, in the thicknesses of 0.6 mm and 1.5 mm, showed fracture resistance exceeding the maximum masticatory forces. / O objetivo do estudo foi avaliar, in vitro, a resist?ncia ? fratura de facetas oclusais, confeccionadas por CAD/CAM, com os materiais Lava Ultimate, e.max CAD e Vita Enamic nas espessuras de 0,6 mm e 1,5 mm. Setenta terceiros molares humanos h?gidos foram aleatoriamente divididos em sete grupos (n=10) de acordo com as vari?veis material e espessura, tendo os dentes h?gidos como controle. A raiz dos dentes foi inserida em resina acr?lica quimicamente ativada e os dentes receberam um preparo para simular eros?o avan?ada da superf?cie oclusal. As restaura??es oclusais foram confeccionadas por meio da tecnologia CAD-CAM, sendo cimentadas ao preparo com sistemas adesivos e cimentos resinosos. Ap?s armazenagem em ?gua destilada a 37 ?C por 24 h, as amostras foram submetidas ? ciclagem mec?nica (1 milh?o de ciclos com carga de 100 N). Na sequ?ncia, os dentes h?gidos e as amostras com as facetas oclusais foram submetidas ao ensaio de resist?ncia ? fratura em m?quina de ensaio universal com velocidade de 1 mm/min. As falhas foram classificadas em repar?veis e irrepar?veis. De acordo com ANOVA de duas vias, a intera??o entre material e espessura foi significativa (p=0,013). A maior resist?ncia ? fratura foi obtida para o e.max CAD na espessura de 1,5 mm (4995 N), sendo estatisticamente superior aos demais grupos (p<0,05). A menor resist?ncia ? fratura foi obtida para o Vita Enamic na espessura de 0,6 mm (2973 N), n?o diferindo estatisticamente do e.max CAD 0,6 mm (3067 N), Lava Ultimate 0,6 mm (3384 N), Vita Enamic 1,5 mm (3540 N) e Lava Ultimate 1,5 mm (3584 N) (p>0,05). De acordo com ANOVA de uma via, a resist?ncia ? fratura dos dentes h?gidos (3991 N) n?o diferiu estatisticamente dos dentes com facetas oclusais (p>0,05). As falhas foram predominantemente do tipo repar?vel, com exce??o dos dentes h?gidos e Lava Ultimate 1,5 mm. As facetas oclusais em Lava Ultimate, e.max CAD e Vita Enamic, nas espessuras de 0,6 mm e 1,5 mm, demonstraram resist?ncia ? fratura que excede as for?as mastigat?rias m?ximas.

Kan Yeuk Ming. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1994. / Chapter 1. --- INTRODUCTION --- p.1 / Chapter 1.1 --- Motivation --- p.1 / Chapter 1.2 --- Objectives --- p.2 / Chapter 1.3 --- Report Organization --- p.3 / Chapter 2. --- RETROSPECT OF NON-MANIFOLD SOLID MODELING --- p.5 / Chapter 2.1 --- Geometric Modeling --- p.5 / Chapter 2.2 --- Euclidean Space and Topological Space --- p.6 / Chapter 2.3 --- Domains of Solid and Non-Manifold Geometric Modeling --- p.8 / Chapter 2.3.1 --- r-set Domain --- p.8 / Chapter 2.3.2 --- Manifold Domain --- p.9 / Chapter 2.3.3 --- Adjacency Form of Topology --- p.11 / Chapter 2.3.4 --- Cell Complex --- p.13 / Chapter 2.4 --- Representation Schemes of Solid and Non-Manifold Geometric Modeling --- p.14 / Chapter 2.4.1 --- Spatial Decomposition --- p.14 / Chapter 2.4.2 --- Constructive Solid Geometry (CSG) --- p.15 / Chapter 2.4.3 --- Boundary Representations (B-rep) --- p.17 / Chapter 2.5 --- Summary --- p.20 / Chapter 3. --- BOOSTING UP THE SPEED OF BOOLEAN OPERATIONS --- p.21 / Chapter 3.1 --- Solid Modeling with Specialized Hardware --- p.22 / Chapter 3.1.1 --- Modeling with a 4x4 Determinant Processor --- p.22 / Chapter 3.1.2 --- Ray Casting Engine --- p.24 / Chapter 3.2 --- Solid Modeling with General Purposed Parallel Computer --- p.25 / Chapter 3.2.1 --- Modeling with Shared Memory Parallel Computer --- p.27 / Chapter 3.2.2 --- Modeling with SIMD Massively Parallel Computer --- p.27 / Chapter 3.2.3 --- Modeling with MIMD Distributed Memory Parallel Computer --- p.30 / Chapter 3.3 --- Summary --- p.33 / Chapter 4. --- OVERVIEW OF DECmpp 12000/Sx/8K --- p.34 / Chapter 4.1 --- System Architecture --- p.34 / Chapter 4.1.1 --- DECmpp Sx Front End --- p.34 / Chapter 4.1.2 --- DECmpp Sx Data Parallel Unit --- p.35 / Chapter 4.1.2.1 --- Array Control Unit --- p.35 / Chapter 4.1.2.2 --- Processor Element Array --- p.35 / Chapter 4.1.2.3 --- Processor Element Communication Mechanism --- p.36 / Chapter 4.2 --- DECmpp Sx Programming Language --- p.37 / Chapter 4.2.1 --- Variable Declarations --- p.37 / Chapter 4.2.2 --- Plural Pointers --- p.38 / Chapter 4.2.3 --- Processor Selection by Conditional Expressions --- p.39 / Chapter 4.2.4 --- Processor Element Communications --- p.39 / Chapter 4.3 --- Summary --- p.40 / Chapter 5. --- ARCHITECTURE OF THE NON-MANIFOLD GEOMETRIC MODELER --- p.41 / Chapter 6. --- SEQUENTIAL MODELER --- p.43 / Chapter 6.1 --- Sequential Half-Wedge structures (SHW) --- p.43 / Chapter 6.2 --- Incremental Topological Operators --- p.51 / Chapter 6.3 --- Sequential Boolean Operations --- p.58 / Chapter 6.3.1 --- Complementing the subtracted model --- p.59 / Chapter 6.3.2 --- Computing intersection of geometric entities --- p.59 / Chapter 6.3.3 --- Construction of sub-faces --- p.53 / Chapter 6.3.4 --- Extraction of resultant topological entities --- p.64 / Chapter 6.4 --- Summary --- p.67 / Chapter 7. --- PARALLEL MODELER --- p.68 / Chapter 7.1 --- Parallel Half-Wedge Structure (PHW) --- p.68 / Chapter 7.1.1 --- Pmodel structure --- p.69 / Chapter 7.1.1.1 --- Phwedge structure --- p.69 / Chapter 7.1.1.2 --- Psurface structure --- p.71 / Chapter 7.1.1.3 --- Pedge structure --- p.72 / Chapter 7.1.2 --- Pmav structure --- p.73 / Chapter 7.2 --- Parallel Boolean Operations --- p.74 / Chapter 7.2.1 --- Complementing the subtracted model --- p.75 / Chapter 7.2.2 --- Intersection computation --- p.79 / Chapter 7.2.2.1 --- Distributing geometric entities --- p.80 / Chapter 7.2.2.2 --- Vertex-Vertex intersection --- p.89 / Chapter 7.2.2.3 --- Vertex-Edge intersection --- p.89 / Chapter 7.2.2.4 --- Edge-Edge intersection --- p.89 / Chapter 7.2.2.5 --- Vertex-Face intersection --- p.90 / Chapter 7.2.2.6 --- Edge-Face intersection --- p.92 / Chapter 7.2.2.7 --- Face-Face intersection --- p.93 / Chapter 7.2.3 --- Constructing sub-faces --- p.98 / Chapter 7.2.4 --- Extraction and construction of resultant topological entities --- p.100 / Chapter 7.3 --- Summary --- p.106 / Chapter 8. --- THE PERFORMANCE OF PARALLEL HALF-WEDGE MODELER --- p.108 / Chapter 8.1 --- The performance of converting sequential to parallel structure --- p.111 / Chapter 8.2 --- The overall performance of parallel Boolean operations --- p.112 / Chapter 8.3 --- The percentage of execution time for individual stages of parallel Boolean operations --- p.119 / Chapter 8.4 --- The effect of inbalance loading to the performance of parallel Boolean operations --- p.121 / Chapter 8.5 --- Summary --- p.125 / Chapter 9. --- CONCLUSIONS AND SUGGESTIONS FOR FURTHER WORK --- p.126 / Chapter 9.1 --- Conclusions --- p.126 / Chapter 9.2 --- Suggestions for further work --- p.127 / APPENDIX / Chapter A. --- SEQUENTIAL HALF-WEDGE STRUCTURE --- p.A-1 / Chapter B. --- COMPUTATION SCHEME IN CHECKING A FACE LOCATING INSIDE THE FACES OF A SOLID --- p.A-3 / Chapter C. --- ALGORITHM IN FINDING A HALF-WEDGE WITH A DIRECTION CLOSEST FROM A REFERENCE HALF-WEDGE --- p.A-5 / Chapter D. --- PARALLEL HALF-WEDGE STRUCTURE --- p.A-7 / REFERENCES --- p.A-10

於參數化和特徵模型的變形中保持幾何特徵是CAD建模中一項新的挑戰。這篇論文提出了一個以限制為基礎去進行變形的系統。此系統結合了自由曲面和特徵模型建模的好處，而且容許更自由的工程設計。 / 本方法可分為三個主要步驟。以常用的變形技術去改變一個模型的形狀，包括自由變形及軸向變形，然後參數特徵會根據用戶的要求去分拆為一系列基本的限制，最後目標特徵將會以逐步增量的優化技術去重建。 / 這篇論文提出了一個逐步增量的方法為優化中提供導引。這個優化是於維持所有提供的限制下盡量減少變形後模型的改變。另外，於一組的限制中以一個基准為參考，能使本系統更有效的運行。最後，我們也會展示一些使用本系統以限制為基礎去進行變形的結果。 / To retain geometric features in the deformation of a parametric and feature-based model is a new challenge for CAD modeling. This thesis presents a constraints based deformation framework. This framework combines the advantage of free-form modeling with feature based modeling, and allows engineering design to be performed in a free-form manner. / The proposed method can be divided into three major steps. An object is deformed by common deformation techniques such as FFD and axial deformation. Parametric features are divided into systems of primitive constraints based on user specification. The targeting features are reconstructed by the use of incremental optimization technique. / An incremental constrained deformation is introduced. It is used to provide hints for the optimization. The optimization is to minimize the changes in the deformed model subjected to all the provided constraints. For a structural constraint specified with a group of constraints, it would be better to use a reference datum for all its component constraints. We show numerous results of constraints retained models using our framework. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Tang, Wing Shing. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 84-86). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts also in Chinese. / Chapter 1 --- INTRODUCTION --- p.3 / Chapter 1.1 --- Aims and Objectives --- p.4 / Chapter 1.2 --- Report Organization --- p.5 / Chapter 2 --- BACKGROUND AND LITERATURE REVIEW --- p.7 / Chapter 2.1 --- Mesh Editing Techniques --- p.7 / Chapter 2.1.1 --- Mesh Deformation Techniques --- p.7 / Chapter 2.1.2 --- Detail Preserving Techniques --- p.9 / Chapter 2.2 --- Optimization Techniques --- p.11 / Chapter 2.2.1 --- Optimization Techniques --- p.11 / Chapter 2.2.2 --- Linear Programming --- p.12 / Chapter 2.2.2.1 --- Simplex Method --- p.12 / Chapter 2.2.2.2 --- Interior Point Method --- p.12 / Chapter 2.2.2.2.1 --- Primal-Dual Interior Point Method --- p.13 / Chapter 2.2.3 --- Nonlinear Programming --- p.14 / Chapter 2.2.3.1 --- Sequential Quadratic Programming --- p.14 / Chapter 2.2.3.2 --- Reduced Gradient Methods --- p.14 / Chapter 2.2.3.3 --- Interior Point Methods --- p.15 / Chapter 2.2.4 --- Optimization Solver --- p.15 / Chapter 2.2.4.1 --- KNITRO --- p.16 / Chapter 3 --- SPECIFICATION OF CONSTRAINTS --- p.18 / Chapter 3.1 --- Constraints --- p.18 / Chapter 3.1.1 --- Constraints with Reference Points --- p.22 / Chapter 3.1.2 --- Constraints with Reference Variables --- p.24 / Chapter 3.1.3 --- Reference Vector Constraints --- p.26 / Chapter 3.1.4 --- Constraints with Reference Datum --- p.27 / Chapter 3.1.4.1 --- Planer Constraint with References --- p.28 / Chapter 3.1.4.2 --- Collinear Constraint with References --- p.29 / Chapter 3.1.4.3 --- Circular Constraint with References --- p.30 / Chapter 3.2 --- Redundant Constraints --- p.31 / Chapter 4 --- CONSTRAINED OPTIMZATION --- p.32 / Chapter 4.1 --- Objective Function --- p.32 / Chapter 4.2 --- Incremental Constrained Deformation --- p.39 / Chapter 4.3 --- The Scaling Problem --- p.43 / Chapter 5 --- CASE STUDIES --- p.44 / Chapter 5.1 --- Maintain Individual Engineering Features --- p.44 / Chapter 5.2 --- Maintain Pattern between Engineering Features --- p.49 / Chapter 5.3 --- Maintain Relationship between Engineering Features --- p.51 / Chapter 5.4 --- Implementation Issue --- p.66 / Chapter 6 --- TESTS AND RESULTS --- p.68 / Chapter 6.1 --- Constraints with References --- p.68 / Chapter 6.2 --- Level Of Detail --- p.71 / Chapter 6.3 --- Incremental Method --- p.73 / Chapter 6.4 --- Comparison --- p.76 / Chapter 7 --- FURTHER WORK AND CONCLUSIONS --- p.81 / Chapter 7.1 --- Recommendation for Further Work --- p.81 / Chapter 7.2 --- Conclusions --- p.82 / REFERENCES --- p.84

The automotive engineering process is characterized by a long and complex design process which starts with the first sketches in the preliminary design phase and proceeds to the final detailed CAD and physical models. In this process, every design phase includes different process steps and tasks which are closely interconnected with each other. Therefore the different design stages demand capable Computer Aided Design (CAD) systems which are able to handle the different kinds of design information created and manipulated in the process. Currently in automotive practice, parametric and associative (PA) CAD systems are widely applied in the product development process. Such systems allow design knowledge to be embedded in CAD models by means of rules and formulae. In addition, CAD parts and assemblies can be generated faster and easier by modification of design parameters and therefore there is a possibility to create different CAD model variants which are based on the same CAD model. The four key element of the following work are (a) to identify the problems during the design process with parametric and associative (PA) methods during a three year of study and also the analysis of the literature survey. Furthermore (b) in this study the author will develop and implement a newly developed PA design approach (PARAMASS) in a ―real‖ industrial context. Beside this the following work will (c) discuss the issues which are important during the implementation of the developed PA approach in an industrial surrounding. The last key element (d) is to develop an evaluation approach for the PARAMASS approach during the application in an industrial context. In this case the author will be able to do action research in the industry and get first hand information during the accomplishment of these key elements. This thesis presents the results of a research programme carried out using the design research methodology of Blessing and Chakrabarti, aimed at understanding the difficulties and challenges faced by designers in using PA CAD systems and then developing and evaluating an integrated approach to the creation of PA CAD models in an automotive power train design context. Firstly, this thesis presents a review of the state of the art in PA design methods and approaches and also reviews previous research on the development of methodologies for the construction of PA CAD models. It then presents results of a descriptive study of the use of PA CAD tools and methods in vehicle power train design in an automotive original equipment manufacturer and in companies in its supply chain using questionnaires, interviews, tests and other field studies with a number of practising engineers. This study identified a number of issues faced by designers in the use of PA CAD tools and allowed the requirements for improved methods for the use of PA CAD tools to be formulated and indicators identified for their evaluation. Based on the results of the descriptive study a new integrated parametric associative (PA) approach for the design process of power train components was created in a prescriptive study stage. The approach, called PARAMASS, allows designers to construct and modify models in a methodical way based on three main phases: a specification phase to prepare the relevant parameters and associative relationships, a structuring phase that allows part and assembly structures to be created and a modification phase in which the created parametric and associative information can be modified and changed. The method makes extensive use of predefined structures matrix approaches adapted from the Design Structure Matrix. The prescriptive study phase of the research was followed by a second descriptive study to evaluate and investigate in both a qualitative and quantitative way the changes achieved by the PARAMASS approach. The qualitative evaluation was based on the Goal Question Metric approach and showed that there are advantages related to the reusability aspects like learning, application and acceptance of the developed integrated approach. The quantitative evaluation was based on the Use Case approach and demonstrated good advantages in applying the developed approach, but dependent on the complexity of the created parts and assemblies.

Kinetic energy storage via flywheels is an emerging avenue for hybrid vehicle research, offering both high energy and power density compared to more established electric and hydraulic alternatives. However, connecting the high speed flywheel to the relatively low speed drivetrain of the vehicle is a persistent challenge, requiring a transmission with high variability and efficiency. A proposed solution drawing inspiration from the electrical domain is the Switch-Mode Continuously Variable Transmission (SM CVT), which uses a high speed clutch to transfer energy to a torsion spring in discrete pulses with a variable duty cycle. The greatest limitation to the performance of this system is the speed and efficiency of commercial clutch technology. It is the goal of this thesis to develop a novel clutch which meets the actuation speed, controllability, and efficiency requirements of the SM CVT, with potential for reapplication in other rotary mechanical systems with switching functionality. The performance demands of the clutch were derived via a theoretical design case based on the performance requirements of a typical passenger vehicle, indicating the need for a sub-millisecond engagement and disengagement cycle. This is not met by any conventional clutch. Several concepts were considered across the fluid, electromagnetic and mechanical energy domains. A final concept was chosen which employs a friction disk style architecture, with normal force produced by compressing springs via an axial cam mounted to the flywheel. To control duty cycle, the cam was designed with a radially varying profile such that increasing radial position results in proportionally increasing ratio of high dwell to low dwell. Three synchronized followers are then translated radially on the cam by a control linkage. Analysis of the follower train dynamics and system stiffness were carried out to inform the design of a scaled benchtop prototype. Experimental testing was carried out to characterize the performance of the prototype. It was found that the intended functionality of the design was achieved, with discrete energy transfer accomplished via pulsing of the clutch. However, maximum efficiency was only 33% and torque capacity was only 65% of the intended 70Nm. Significant opportunity exists for improvement of the clutch performance in future research.

BACKGROUND: Delirium is an “acute change in cognition” prevalent in the elderly population (9). It is a clinical diagnosis which results from complex relationships between patient vulnerability and precipitating medical factors (2,9). Delirium has a complex relationship with dementia and often these two cognitive impairments occur together. While delirium occurrence is exceptionally high in dementia patients, it’s recognition by physicians is unfortunately low (10). Delirium prevalence in dementia patients can be as high as 80% and failure to recognize occurs in as many as 75% of cases (10). Recognition of delirium is important due to its association with poor outcomes and potential for prevention by avoiding precipitating causes. Common poor outcomes associated with delirium include, prolonged cognitive and physical impairment, longer hospital stays, institutionalization and death. With the increasing aging population and the rising cost of healthcare in the United States more attention has been focused on better detection of costly conditions including delirium. Efforts have been made to develop tools for universal screening to aid in the recognition of delirium; however, these are not widely used outside of research. One of the challenges in recognizing delirium is that providers lack knowledge of the patient’s baseline cognitive status, making it difficult to determine whether an acute change has occurred. Caregivers are an untapped resource, holding this key piece of information, in the early recognition of delirium. SPECIFIC AIMS: The goal of this study is to build an argument for the implementation of a training program which would teach caregivers to complete the Family Confusion Assessment method (FAM-CAM) interviews on their loved ones at home in an effort to aid in the early recognition of delirium. This will be accomplished through the followings specific aims. Aim 1: Complete a comprehensive literature review to assess the need for family based screening for delirium. An attempt will be made to identify a gap in the literature for efficient and effective delirium screening and utilization of family caregivers. Aim 2: Data collected in a completed prospective observational study “Family Member Identification of Delirium in the Emergency Department” will be analyzed to assess family caregivers’ role in recognition of delirium, and family caregivers’ receptiveness and interest in a training program. METHODS: The information in this thesis used to build the argument for FAM-CAM training was found through a comprehensive review of published literature on delirium. Resources were found mainly through Pub Med and the Hospital Elder Life Program’s Delirium Bibliography. The study; “Family Member Identification of Delirium in the Emergency Department” enrolled 63 patients for CAM only and 108 Dyads for CAM and FAM-CAM with a total N of 171. RESULTS: Results showed that in 60% of cases of delirium that were recognized by physicians, a caregiver was present and provided information on the patient. Without being made aware of potential benefits of FAM-CAM training, 34% of caregivers reported that training on the instrument would be helpful, and 46% showed interest in participating in the training. Concurrent with current research a high percentage of patients with history of dementia were found to be delirious, further exemplifying the link of risk between these two conditions and identifying caregivers of dementia patients as a good population to implement FAM-CAM training. DISCUSSION: This literature review and accompanying study data suggests that, if implemented, FAM-CAM training could lead to potential future benefits including, reduced delirium associated healthcare cost, improved patient outcomes, and an improved experience for caregivers.

OBJECTIVE: The purpose of this study is to evaluate the experimental properties of zirconia-based ceramics. METHODS: Zirconia bars were veneered to 2mm total thickness. Veneering-method groups included: 1.Hand-layered feldsparthic porcelain (VM=VitaVM9,Vident) and fluorapatite glass-ceramic (CR=IPSe.maxCeram,IvoclarVivadent); 2.Pressed feldspathic porcelain (PM=VitaPM9,Vident) and fluorapatite glass-ceramic (ZP=IPSe.maxZirPress,IvoclarVivadent); 3.CAD/CAM milled feldspathic ceramic (TF=VitablocsTriluxeForte,Vident) and lithium-disilicate glass-ceramic (CAD=IPSe.maxCAD,IvoclarVivadent). CAD/CAM veneers were either cemented with resin cements (P=Panavia21,KurarayDental), (R=RelyXUltimate,3M ESPE), (M=MultilinkAutomix,IvoclarVivadent) or fused with fusion glass-ceramic (C=CrystalConnect,IvoclarVivadent). A Three-point-bending test was performed. For group VM,PM,TF-M,TF-C,CAD-M,CAD-C, ten more bars were prepared and aged with cyclic loading and thermocycling before testing. Zirconia bars (PrettauZirconia,Zirkonzahn;inCorisTZI,Sirona;ZirluxFC,PentronCeramics) specimens were prepared and polished. The specimens were divided into 3 groups: control, self-glaze fired, and glazed groups. A Three-point bending test was performed. Veneered zirconia crowns were made. Feldspathic porcelain was applied to zirconia coping. Bevel cut on porcelain was made to simulate porcelain chipping. The crowns were then divided into 4 different groups according to repair materials including: 1.Conventional-resin composite (TetricEvoCeram,IvoclarVivadent) 2.Flowable-resin composite (G-aenialUniversalFlo,GCamerica) 3.Cemented CAD/CAM milled feldspathic ceramic (VitaTriluxForte,Vident) 4.Cemented CAD/CAM milled lithium-disilicate glass-ceramic (IPSe.maxCAD,IvoclarVivadent). Each crown underwent thermocycling. The test was performed by loading force on the center of repaired part to record load-to-failure. RESULTS: There were significant differences in the failure loads of non-aged bilayered veneer-zirconia bars. Aging experiment revealed a significant difference in failure load between non-aged and aged bars in groups VM and PM, but not in the groups with CAD/CAM milled veneers. There was significant influence of surface treatments on flexural strength of zirconia specimens. Post-hoc test showed that glazed group had significant lower flexural strength than other groups. Crowns repaired with CAD/CAM ceramics showed significant higher failure load than resin composite. Repairing with lithium-disilicate glass ceramic yielded the highest load-to-failure of the specimens. CONCLUSIONS: - Veneer materials, veneering methods, and cement materials have a significant effect on the failure load of bilayered veneer- zirconia. CAD/CAM veneer-zirconia is not susceptible to aging performed in this study. - Glazing decreased the flexural strength of high translucent zirconia. - Veneered zirconia crowns repaired with CAD/CAM ceramic materials have significantly higher load-to-failure than veneered crowns repaired with resin composite. / 2018-09-28T00:00:00Z

Introdução: As alterações anatômicas do fêmur proximal ou do acetábulo, como as decorrentes das sequelas da epifisiólise do fêmur proximal, da displasia do quadril da doença de Legg-Perthes-Calvé, podem levar ao desenvolvimento da artrose do quadril. No entanto, em torno de 80% dos indivíduos que desenvolvem essa doença têm uma anatomia óssea considerada normal. Ainda assim, surgiu a hipótese que alterações sutis do fêmur proximal ou do acetábulo, denominadas, respectivamente, cam e pincer, poderiam gerar um contato anormal entre essas estruturas ósseas, desencadear lesão condral e, como consequência, a artrose do quadril. Esse mecanismo foi denominado impacto fêmoro-acetabular. No entanto, a comprovação da relação entre o impacto e a artrose do quadril depende da uniformização dos critérios diagnósticos do cam e do pincer, ainda escassa e variável na literatura. Dessa forma, será possível a definição da prevalência e história natura do impacto fêmoro-acetabular e da sua relação com a artrose do quadril. Objetivo: Avaliar a prevalência do impacto fêmoro-acetabular tipo cam e tipo pincer em uma amostra de indivíduos assintomáticos. Pacientes e Métodos: Foram estudados 106 indivíduos assintomáticos (65 homens e 41 mulheres), com idade entre 20 e 40 anos. A condição determinante para a inclusão no estudo foi à ausência de história de dor no quadril ao longo da vida. Foram obtidas radiografias em ântero-posterior e Dünn 45°. A presença de cam foi determinada por um ângulo alfa, arbitrado, de 55° e a presença de pincer, quando observado o sinal da parede posterior e/ou o sinal de crossover. Resultados: Foi observada prevalência de cam de 29%; o sinal do crossover e da parede posterior ocorreram, respectivamente, em 20% e 29% dos indivíduos estudados. Pelo menos uma das imagens de impacto fêmoro-acetabular estava presente em 65% dos indivíduos da amostra. Conclusão: A prevalência encontrada das imagens de impacto fêmoro-acetabular (65%) está acima daquelas relatadas na literatura. É necessária a ampliação do estudo para confirmar os resultados encontrados e a realização de estudos prospectivos bem controlados para avaliar o papel do cam e do pincer no desenvolvimento da artrose do quadril. / Background: Anatomical abnormalities of the proximal femur or the acetabulum, such as those resulting from the consequences of slipped epiphyses of the proximal femur, the hip dysplasia of Legg-Calve-Perthes disease, could lead to the development of hip osteoarthrosis. Nevertheless, around 80% of individuals who develop this condition have a bone anatomy considered normal. Still, the hypothesis arose that subtle alterations of the proximal femur or the acetabulum, called, respectively, cam and pincer, could generate an abnormal contact between these bony structures, triggering chondral lesion and as a consequence, arthritis of the hip. This mechanism has been named femoroacetabular impingement. Nevertheless, evidence of the relationship between the impact and osteoarthritis of the hip depends on the standardization of diagnostic criteria of cam and pincer, still scarce and variable in the literature. Thus it will be possible to define the prevalence and natural history of femoroacetabular impingement and its relationship with hip osteoarthrosis. Aim: To determine the prevalence of cam-type and pincer-type femoroacetabular impingements in asymptomatic subjects. Patients and Methods: Were studied 106 asymptomatic subjects (65 males and 41 females) aged between 20 and 40 years. The determining condition for inclusion in the study was the absence of history of hip pain throughout life. Radiographs were obtained in anteroposterior pelvic view and Dunn 45° view. The presence of cam was determined by an angle alpha, arbitrated, 55 ° and the presence of pincer when the observed the posterior wall and / or crossover signs. Results: A prevalence of 29% of cam, and 20% and 29% of crossover sign and posterior wall sign respectively was found. At least, one of those radiographic signs of femoroacetabular impingement was found in 65% (68) of the cases. Conclusion: In conclusion, the prevalence of images of femoroacetabular impingement (65%) is above those reported in the literature. Increase of the study is necessary to verify the results found, and the performance of well-controlled prospective studies to evaluate the role of the cam and pincer in the development of osteoarthritis of the hip.

Estágio realizado na Lismolde 2, Ld.ª e orientado pelo Eng.º Marco Ruivo / Tese de mestrado integrado. Engenharia Mecânica. Faculdade de Engenharia. Universidade do Porto. 2008