Product visualization in AR/VR applications requires a largely manual process of data preparation. Previous publications focus on error-free triangulation or transformation of product structure data and display attributes for AR/VR applications. This paper focuses on the preparation of the required geometry data. In this context, a significant reduction in effort can be achieved through automation. The steps of geometry preparation are identified and examined concerning their automation potential. In addition, possible couplings of sub-steps are discussed. Based on these explanations, a structure for the geometry preparation process is proposed. With this structured preparation process, it becomes possible to consider the available computing power of the target platform during the geometry preparation. The number of objects to be rendered, the tessellation quality, and the level of detail (LOD) can be controlled by the automated choice of transformation parameters. Through this approach, tedious preparation tasks and iterative performance optimization can be avoided in the future, which also simplifies the integration of AR/VR applications into product development and use. A software tool is presented in which partial steps of the automatic preparation are already implemented. After an analysis of the product structure of a CAD file, the transformation is executed for each component. Functions implemented so far allow, for example, the selection of assemblies and parts based on filter options, the transformation of geometries in batch mode, the removal of certain details, and the creation of UV maps. Flexibility, transformation quality, and timesavings are described and discussed.

La prise en compte des pertes fer dans les machines électriques est une étape cruciale lors du processus de conception. L'objectif de ce travail a donc été de valider l'implémentation d'un modèle de pertes fer tout en effectuant une modélisation précise des machines électriques étudiées. Le choix s'est porté sur l'utilisation de modèles de calcul des pertes en post-traitement d'un code par éléments finis. Ainsi, différents modèles analytiques ont été comparés en régime sinusoïdal et non sinusoïdal (sans cycles mineurs) en termes de précision, afin de choisir le plus adapté pour une implantation dans code_Carmel. Par ailleurs, nous avons montré que la prise en compte des cycles mineurs peut être améliorée en remplaçant le terme classique de Steinmetz par un modèle d'hystérésis ou par un modèle analytique adapté. L'implémentation et la précision du modèle analytique ont été évaluées d'abord sur des systèmes simples puis sur plusieurs machines tournantes. La comparaison des résultats simulés avec les mesures issues des essais à vide montre une bonne concordance et démontre la capacité du modèle à estimer les pertes fer avec une bonne précision pour une large gamme de machines électriques et pour les deux types d'alimentations utilisés (sinusoïdale et MLI).

This research utilizes CFD to analyze blood flow through pathways representative of central shunts, commonly used as part of the Fontan procedure to treat cyanotic heart disease. In the first part of this research, a parametric study of steady, Newtonian blood flow through parabolic pathways was performed to demonstrate the effect that flow pathway curvature has on wall shear stress distribution and flow energy losses. In the second part, blood flow through two shunts obtained via biplane angiograms is simulated. Pressure boundary conditions were obtained via catheterization. Results showed that wall shear stresses were of sufficient magnitude to initiate platelet activation, a precursor for thrombus formation. Steady results utilizing time-averaged boundary conditions showed excellent agreement with the time-averaged results obtained from pulsatile simulations. For the points of interest in this research, namely wall shear stress distribution and flow energy loss, the Newtonian viscosity model was found to yield acceptable results.

A motivação para o presente trabalho foi o desejo de investigar métodos e ferramentas que fossem capazes de auxiliar engenheiros a desenvolver melhores projetos de sistemas de automação. Investigaram-se então quais seriam as contribuições da engenharia de software e da engenharia de controle para alcançar esse objetivo: a primeira destacou-se pelos métodos e ferramentas aplicáveis às fases de levantamento de requisitos e análise, em que os sistemas podem ser expressos através da UML; a segunda contribuiu com blocos funcionais, especialmente os orientados a eventos da norma IEC 61499, e ferramentas para implementação e testes. Diversos autores sugerem a unificação entre as técnicas de orientação a objetos expressas através da UML e o projeto de sistemas por meio de blocos funcionais orientados a eventos da norma IEC 61499, para que os engenheiros de cada uma das áreas citadas continuassem trabalhando com técnicas e ferramentas próprias no desenvolvimento de sistemas de automação, mas de maneira colaborativa. Nesta pesquisa estudou-se a maneira pela qual vêm sendo feitos os mapeamentos entre a UML e a norma IEC 61499 do ponto de vista teórico, embora com intenção de implementação de ferramentas para ajudar nessa conversão. Estudaram-se também as ferramentas criadas para automatizar essa transformação e para auxiliar no projeto de sistemas de automação distribuídos, principalmente segundo a visão da norma IEC 61499. A partir daí, pôde-se oferecer as seguintes contribuições: quanto aos métodos, sugerir um novo método de mapeamento UML-IEC 61499 simplificado, com o uso, em UML, de um vocabulário menos atrelado à norma IEC 61499 (ao contrário do que acontecia com os métodos estudados); e sugerir a expressão de requisitos temporais quanto aos sistemas de automação (também considerados no contexto da conversão UML-IEC61499); quanto às ferramentas, comparar o modelo lógico da IEC 61499 com o da tecnologia LonWorks; e, a partir daí, demonstrar a viabilidade de criação de uma ferramenta para implementar sistemas de automação LonWorks expressados primeiramente em abstrações da IEC 61499 (obtidas a partir das ferramentas vistas anteriormente). Concluiu-se que é possível, teoricamente, criar uma ferramenta para cobrir todo o ciclo de vida de desenvolvimento de um sistema de automação distribuído, com a implementação deste sendo feita em uma tecnologia de controle de grande aceitação no mercado. Apesar disso, identificou-se ainda que há várias oportunidades de estudo em continuidade a essa pesquisa, como aprofundamento da expressão dos requisitos de QoS e implementação da ferramenta idealizada. / The main motivation of this research was to investigate tools and methods which could help engineers to develop better automation system projects. So, with this aim, the contributions of both software engineering and control engineering areas were investigated: the first offered methods and tools to be used in the requisite elicitation and system analysis project phases, in which the system could be designed in terms of UML models; the latter contributed mainly through implementation and test tools, related to the usage of function blocks, especially the IEC 61499 standard eventoriented ones. Many authors suggest the unification between object-orientation techniques expressed through UML and project methods done with the IEC 61499 event-driven function blocks, so that software engineers and control engineers could keep working with their own area techniques and tools, in the context of an automation system design, but in a collaborative sense. In this work, the mapping between UML and IEC 61499 standard concepts was investigated from a theoretical point of view, even though the intention behind that was to find or generate tools which could automate this kind of conversion. Additionally, other tools related to help engineers in the development of automation systems (particularly those which used IEC 61499 standard abstractions) were also analyzed. After all that, some contributions to this area could be proposed: as for the methods, a new simplified UML-IEC61499 mapping, whose main features are the usage, in UML, of a less IEC 61499-constrained vocabulary (opposite to what happened in the other studied techniques), and the way of expressing automation systems temporal requisites (still related to the UML-IEC61499 conversion context); as for the tools, a comparison between IEC 61499 and the LonWorks technology logical models, which led to the conclusion that it would be possible to implement LonWorks automation systems whose models were expressed at first through IEC 61499 abstractions (mainly those resultant from the usage of UML-IEC61499 conversion tools). The conclusion of this work is that with the development of all these tools and techniques it would be possible to aid engineers through all automation system development phases, and the implementation of such systems could be done with a broadly-accepted control system technology. It was also identified that many other study opportunities were raised by this research, such as discovering ways of expressing other QoS requisites in automation system models, and trying to implement more complete engineering project tools.

A motivação para o presente trabalho foi o desejo de investigar métodos e ferramentas que fossem capazes de auxiliar engenheiros a desenvolver melhores projetos de sistemas de automação. Investigaram-se então quais seriam as contribuições da engenharia de software e da engenharia de controle para alcançar esse objetivo: a primeira destacou-se pelos métodos e ferramentas aplicáveis às fases de levantamento de requisitos e análise, em que os sistemas podem ser expressos através da UML; a segunda contribuiu com blocos funcionais, especialmente os orientados a eventos da norma IEC 61499, e ferramentas para implementação e testes. Diversos autores sugerem a unificação entre as técnicas de orientação a objetos expressas através da UML e o projeto de sistemas por meio de blocos funcionais orientados a eventos da norma IEC 61499, para que os engenheiros de cada uma das áreas citadas continuassem trabalhando com técnicas e ferramentas próprias no desenvolvimento de sistemas de automação, mas de maneira colaborativa. Nesta pesquisa estudou-se a maneira pela qual vêm sendo feitos os mapeamentos entre a UML e a norma IEC 61499 do ponto de vista teórico, embora com intenção de implementação de ferramentas para ajudar nessa conversão. Estudaram-se também as ferramentas criadas para automatizar essa transformação e para auxiliar no projeto de sistemas de automação distribuídos, principalmente segundo a visão da norma IEC 61499. A partir daí, pôde-se oferecer as seguintes contribuições: quanto aos métodos, sugerir um novo método de mapeamento UML-IEC 61499 simplificado, com o uso, em UML, de um vocabulário menos atrelado à norma IEC 61499 (ao contrário do que acontecia com os métodos estudados); e sugerir a expressão de requisitos temporais quanto aos sistemas de automação (também considerados no contexto da conversão UML-IEC61499); quanto às ferramentas, comparar o modelo lógico da IEC 61499 com o da tecnologia LonWorks; e, a partir daí, demonstrar a viabilidade de criação de uma ferramenta para implementar sistemas de automação LonWorks expressados primeiramente em abstrações da IEC 61499 (obtidas a partir das ferramentas vistas anteriormente). Concluiu-se que é possível, teoricamente, criar uma ferramenta para cobrir todo o ciclo de vida de desenvolvimento de um sistema de automação distribuído, com a implementação deste sendo feita em uma tecnologia de controle de grande aceitação no mercado. Apesar disso, identificou-se ainda que há várias oportunidades de estudo em continuidade a essa pesquisa, como aprofundamento da expressão dos requisitos de QoS e implementação da ferramenta idealizada. / The main motivation of this research was to investigate tools and methods which could help engineers to develop better automation system projects. So, with this aim, the contributions of both software engineering and control engineering areas were investigated: the first offered methods and tools to be used in the requisite elicitation and system analysis project phases, in which the system could be designed in terms of UML models; the latter contributed mainly through implementation and test tools, related to the usage of function blocks, especially the IEC 61499 standard eventoriented ones. Many authors suggest the unification between object-orientation techniques expressed through UML and project methods done with the IEC 61499 event-driven function blocks, so that software engineers and control engineers could keep working with their own area techniques and tools, in the context of an automation system design, but in a collaborative sense. In this work, the mapping between UML and IEC 61499 standard concepts was investigated from a theoretical point of view, even though the intention behind that was to find or generate tools which could automate this kind of conversion. Additionally, other tools related to help engineers in the development of automation systems (particularly those which used IEC 61499 standard abstractions) were also analyzed. After all that, some contributions to this area could be proposed: as for the methods, a new simplified UML-IEC61499 mapping, whose main features are the usage, in UML, of a less IEC 61499-constrained vocabulary (opposite to what happened in the other studied techniques), and the way of expressing automation systems temporal requisites (still related to the UML-IEC61499 conversion context); as for the tools, a comparison between IEC 61499 and the LonWorks technology logical models, which led to the conclusion that it would be possible to implement LonWorks automation systems whose models were expressed at first through IEC 61499 abstractions (mainly those resultant from the usage of UML-IEC61499 conversion tools). The conclusion of this work is that with the development of all these tools and techniques it would be possible to aid engineers through all automation system development phases, and the implementation of such systems could be done with a broadly-accepted control system technology. It was also identified that many other study opportunities were raised by this research, such as discovering ways of expressing other QoS requisites in automation system models, and trying to implement more complete engineering project tools.

This thesis is an investigation of the fabrication and assembly methodologies employed in the development of a proof-of-principle prototype electric guitar composed of laminated copolyester. The objective of the project was to develop the processes and procedures to create an optimized physical and visual bond between layers to minimize vibratory dissipation, thus maximizing sustain. A high speed CNC router, abrasive waterjet, laser engraver-cutter, as well as various manual fabrication and assembly methods were investigated in the construction of the guitar prototypes. The lamination processes explored include low-temperature, heat-assisted pressure bonding, solvent and chemical welding, and contact adhesives. The project concluded with the completion of a working guitar comprised of a laminated copolyester body and a traditional bolton wooden neck.

The client-server architecture of STAR-CCM+ allows multiple users to collaborate on a simulation set-up. The effectiveness of collaboration with this architecture is tested and evaluated on five models. The testing of these models is a start to finish set-up of an entire simulation excluding computational time for generating mesh and solving the solution. The different models have distinct differences which test every operation that would be used in a general CFD simulation. These tests focus on reducing the time spent preparing the geometry to be meshed, including setting up for a conformal mesh between multiple regions in conjugate heat transfer models. Results from these five tests show a maximum speed up of 36%.

The application of Computer Simulation and Animation (CSA) in the instruction of engineering dynamics has shown a significant growth in the recent years. The two foremost methods to evaluate the effectiveness of CSA tools, including student feedback and surveys and measuring student change in performance, suggest that CSA modules improve student learning in engineering dynamics. However, neither method fully demonstrates the quality of students’ cognitive changes. This study examined the quality of effects of application of CSA modules on student learning and problem solving in particle dynamics. It also compared CSA modules with textbook-style problem-solving regarding the changes they cause in students’ cognitive process. A qualitative methodology was adopted to design and implement a study to explore the changes in participants’ learning and problem-solving behavior caused by using a CSA module. Collected data were coded and analyzed using the categories of cognitive process based on the Revised Bloom’s Taxonomy. An analysis of the results revealed that the most significant effects were observed in understanding, analyzing, and evaluating. The high frequency of “inference” behavior after working with modules indicated a significant increase in participants’ understanding activity after working with computer modules. Comparing behavior changes of computer-simulation group students with those who worked with a textbook-style example demonstrated that the CSA modules ignited more analytical behavior among students than did textbook-style examples. This study illustrated that improvement in learning due to the application of CSA is not limited to conceptual understanding; CSA modules enhance students’ skills in applying, organizing, and evaluating as well. The interactive characteristics of CSA play a major role in stimulating students’ analytical reasoning and critical thinking in engineering dynamics.

Myocardial infarction (i.e., a heart attack) is the most common heart disease in the United States. Mitral valve regurgitation, or the backflow of blood into the atrium from the left ventricle, is one of the complications associated with myocardial infarction. In this dissertation, a validated model of a sheep heart that has suffered myocardial infarction has been employed to study mitral valve regurgitation. The model was rebuilt with the knowledge of geometrical changes captured with MRI technique and is assigned with anisotropic, inhomogeneous, nearly incompressible and highly non-linear material properties. Patch augmentation was performed on its anterior leaflet, using a simplified approach, and its posterior leaflet, using a more realistic approach. In this finite element simulation, we virtually installed an elliptical patch within the central portion of the posterior leaflet. To the best of the author’s knowledge, this type of simulation has not been performed previously. In another simulation, the effect of patch within the anterior leaflet was simulated. The results from the two different surgical simulations show that patch implantation helps the free edges of the leaflets come close to one another, which leads to improved coaptation. Additionally, the changes in chordal force distributions are also reported. Finally, this study answers a few questions regarding mitral valve patch augmentation surgeries and emphasizes the importance of further investigations on the influence of patch positioning and material properties on key outcomes. The ultimate goal is to use the proposed techniques to assess human models that are patient-specific.

Scale modeling has been commonly used for architectural acoustics but use in other noise control areas is nominal. Acoustic scale modeling theory is first reviewed and then feasibility for small-scale applications, such as is common in the electronics industry, is investigated. Three application cases are used to examine the viability. In the first example, a scale model is used to determine the insertion loss of a rectangular barrier. In the second example, the transmission loss through parallel tubes drilled through a cylinder is measured and results are compared to a 2.85 times scale model with good agreement. The third example is a rectangular cuboid with a smaller cylindrical well bored into it. A point source is placed above the cuboid. The transfer function was measured between positions on the top of the cylinder and inside of the cylindrical well. Treatments were then applied sequentially including a cylindrical barrier around the well, a membrane cover over the opening, and a layer of sound absorption over the well. Results are compared between the full scale and a 5.7 times scale model and correlation between the two is satisfactory.