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M.Ing. / Please refer to full text to view abstract

M.Sc. / The technique known as "Rapid Prototyping" constitutes a technology that is already saving large corporations time and money in respect of prototyping. Currently, Rapid Prototyping machines are, however, still expensive to purchase and maintain. In order to allow more people to make use of Rapid Prototyping machines, certain businesses are specialising in rendering a Rapid Prototyping service. Rapid Prototyping service bureaux render such service by selling machine time. To allow people to make use of the service, designs are submitted across a distance by means of telemanufacturing. To enable a wide variety of users to avail themselves of this service, certain checks and balances must, however, be put into place. These checks and balances must test whether or not a valid job has been submitted, and if so, the submitter has to be assisted in deciding upon settings. In order to submit a job from anywhere in the world, the Internet is harnassed for telemanufacturing. Once remote submission has been made safe and convenient, more businesses and individuals could derive benefit from Rapid Prototyping. This dissertation has, therefore, been undertaken to identify the prerequisites for Rapid Prototyping. Once a job has been submitted, it has to be checked for errors and the user has to be advised on building types and recommendations. For this, an agent is used. In this way, problems are prevented, should faulty jobs be sent to a Rapid Prototyping machine. Once a job has been submitted, it is scheduled by a queue manager in order to maximise machine usage. Rapid Prototyping has the potential in future to become as commonplace as printers. In terms of this technology, a design would, therefore, be printed in three dimensions for instant verification by the user. The very advantage of being able to hold a new product in one's hands is self-evident. The technology that is being developed today will, therefore, be successfully used in future scenarios.

In the production of removable facial prosthetics, Computer-Aided Design and Manufacture (CAD/CAM) is being increasingly explored. This PhD thesis investigates the application of CAD/CAM in the design and production of components that retain the prostheses to the anatomy. Conventional methods of hand-crafting the retention elements are well established but little research has considered producing these elements using CAD/CAM. A fully digital prosthetic workflow has not yet been developed, and the efficacy of using CAD/CAM for retention mechanism design and fabrication remains unclear. This study firstly focuses on defining the requirements for designing extra-oral prosthesis retention mechanisms, by mapping the various stages of conventional practice and obtaining the opinions of practicing clinicians. Secondly, the qualitative findings are applied to develop a fully CAD/CAM process using existing technologies. Scanning, reverse engineering, design and fabrication technologies are trialled and samples of bar-clip mechanisms are produced. The final stage focuses on developing objective methods to evaluate aspects of bar-clip design previously limited to subjective evaluation, and to make an initial comparison of conventional and CAD/CAM bar-clip mechanisms. This focuses on measuring surface and dimensional quality, accuracy of fit and clip retention forces. This study provides an increased knowledge-base of current prosthetic practice; CAD/CAM prosthesis production and evaluation methods; and insight into the attitudes of clinicians towards the integration & implementation of CAD/CAM. The thesis demonstrates that CAD/CAM can be used to design, produce, and integrate bar-clip retention mechanisms in all aspects of the prosthesis production workflow. Digital measurement methods allow an objective evaluation of the important aspects of bar-clip mechanism design, identifying a number of inaccuracies/design flaws that current evaluation techniques fail to identify. The study concludes that the overall CAD/CAM workflow is not yet appropriate for clinical practice but there is potential in the newly developed processes and this drives future work.

Alloy is a lightweight formal modeling tool that generates instances of a software specification to check properties of the design. This work demonstrates the use of Alloy for the rapid development of autonomous vehicle driving protocols. We contribute two driving protocols: a Normal protocol that represents the unpredictable yet safe driving behavior of typical human drivers, and a Connected protocol that employs connected technology for cooperative autonomous driving. Using five properties that define safe and productive driving actions, we analyze the performance of our protocols in mixed traffic. Lightweight formal modeling is a valuable way to reason about driving protocols early in the development process because it can automate the checking of safety and productivity properties and prevent costly design flaws.

Esta investigación examinó el uso de rúbricas de ensamblaje, describiendo su evolución a partir de rúbricas de piezas, y estudió cómo afectan a la autoevaluación de los estudiantes. También se valoró la evaluación de los estudiantes por los instructores, encontrando que, mientras que las rúbricas de ensamblaje fueron parcialmente comprendidas y utilizadas de manera eficiente por los estudiantes, éstas fueron usadas con más éxito por los instructores. En esta investigación se han abordado estrategias diseñadas para mejorar la comunicación de la intención de diseño en modelos CAD, acrecentando así su calidad, con directrices dirigidas a evaluar su eficiencia. Es evidente que se necesitan métricas dirigidas hacia la instrucción de la intención de diseño, ya que la intención de diseño transferida a través de modelos CAD puede realizarse en tres etapas con criterios contradictorios que deben ser equilibrados para llegar a la mejor estrategia de modelado. La investigación ha incluido el desarrollo de un método de validación que demuestra que las rúbricas son dispositivos útiles para garantizar una comunicación consistente de la intención de diseño, y son fundamentales no sólo para evaluar, sino también para comunicar las expectativas del instructor. En esta investigación se examinó cómo definir claramente las cualidades de la intención de diseño para permitir una más fácil evaluación de un ensamblaje CAD. Para todas las dimensiones de la rúbrica, se encontró más concordancia y correlación entre instructores que entre instructores y estudiantes. Existe una correlación moderada/fuerte entre los instructores para las dimensiones de la validez, completitud, concisión y claridad, mientras que existe una ligera correlación para las dimensiones de consistencia e intención del diseño. En segundo lugar, las rúbricas también pueden ser descritas como estáticas o dinámicas. Las rúbricas estáticas, existen sólo en papel, no proporcionan retroalimentación inmediata al educando. Las rúbricas dinámicas realizan cálculos que proporcionan observaciones de evaluación inmediatas al usuario. Además, pueden adaptarse a situaciones específicas dependiendo de la capacidad del usuario. Las rúbricas electrónicas son ideales para rúbricas dinámicas, y permiten el uso y desarrollo de rúbricas adaptativas y adaptables, como se describe a continuación. En tercer lugar, las rúbricas deben ser adaptables lo que debería hacerlas fácilmente comprensibles y fáciles de usar, y adaptativas. Las rúbricas de evaluación se usan cuando un experto determina el progreso pedagógico de un educando, mientras que las rúbricas formativas son empleadas por los propios estudiantes, para trazar su progreso e identificar las deficiencias escolares para las que necesitan apoyo. Las rúbricas se deben refinar y mejorar de forma continuada, en un proceso iterativo y colaborativo, hasta que se alcance un acuerdo satisfactorio, tanto entre evaluadores como entre evaluadores y alumnos. Por ello, se desarrollaron mapas de aserciones que ilustran el modo en que la estrategia de expansión-contracción adapta las rúbricas al progreso del aprendiz de CAD, a la vez que ayudan a comprender las diferentes dimensiones de la rúbrica. Basándose en los experimentos con las rúbricas de ensamblajes, es evidente que las pequeñas diferencias entre los instructores sugieren que la rúbrica de ensamblajes propuesta es lo suficientemente sofisticada como para proporcionar una evaluación acumulativa imparcial del desempeño del alumno. En consecuencia, se puede afirmar con confianza que los evaluadores pueden usarse indistintamente sin sacrificar la precisión. Sin embargo, la rúbrica de ensamblaje posee una eficacia finita para producir una autoevaluación formativa de las habilidades de ensamblaje CAD para nuevos alumnos. / This research examined the use of assembly rubrics, described how they evolved from parts rubrics, and studied how they affect student self-evaluation. Instructor assessment of students was also evaluated, finding that while the assembly rubrics were partially understood and effectively used by the students, they were more successfully utilized by the instructors. Strategies designed to improve design intent communication in CAD models, in order to enhance their quality, with guidelines targeted to evaluate efficiency, have been addressed with this research. It is apparent that metrics directed toward the instruction of design intent are needed, since design intent transferred through CAD models can be performed at three stages with competing tradeoffs that must be balanced to arrive at the best modeling strategy. Research included the development of a validation approach that reflects that rubrics are valuable devices to expedite consistent design intent communication, and are vital not only for evaluation, but also for the communication of instructor expectations. This research examined how to clearly define qualities of design intent to enable easier CAD assembly assessment. It has been found that there is more inter-rater agreement and correlation between instructors than between instructors and students, for all rubric dimensions. There is strong to moderate correlation between instructors for the dimensions of validity, completeness, conciseness, and clarity, while slight correlation exists for the dimensions of consistency and design intent. Secondly, rubrics can also be described as being either static or dynamic. Static rubrics, existing in paper form only, do not provide immediate feedback to the learner. Dynamic rubrics perform calculations that provide immediate evaluative observations to the user. Besides, they can be independently adapted to specific situations depending on the capability of the user. Electronic rubrics are ideally suited for dynamic rubrics, and permit the use and development of both adaptable and adaptive rubrics, as described next. Thirdly, rubrics need to be adaptable which should make them easily understood and user-friendly, and adaptive (rubric can change itself, depending on the usage pattern). Evaluative rubrics are used when an expert determines the pedagogical progress of a learner, while formative rubrics are employed by the learners themselves, in order to chart their progress and identify scholastic deficiencies that are in need of remediation. Rubrics must be continually refined and improved, in an iterative, collaborative process, until satisfactory agreement is attained, both between raters, but also between raters and learners. Thus, assertions maps were developed, illustrating how the expand-contract strategy adapts the rubrics to CAD trainee progress, while assisting the understanding of the different rubric dimensions. Based on the assembly rubric experiments, it is apparent that the small differences between instructors suggests that the proposed assemblies rubric is sufficiently sophisticated to furnish an unbiased accumulative assessment of student performance. Accordingly, it can be confidently stated that raters can be used interchangeably without sacrificing accuracy. However, the assembly rubric possesses finite efficacy to produce formative self-evaluation of CAD assembly skills for new learners. / Aquesta investigació examinà l'ús de rúbriques de acoblament, descrivint la seua evolució a partir de rúbriques de peces, i estudià cóm afecten a la autoavaluació dels estudiants. També es va valorar la avaluació dels estudiants per els instructors, trobant que, mentre que les rúbriques de acoblament van ser parcialment compreses i fetes servir de manera eficient per els estudiants, van ser usades amb mes èxit per els instructors. En aquesta investigació s'han abordat estrategues dissenyades per a millorar la comunicació de la intenció de disseny en models CAD, creixentat així la seua qualitat, amb directrius dirigides a avaluar la seua eficiència. Es evident que es necessiten mètriques dirigides cap a la instrucció de la intenció de disseny, ja que la intenció de disseny transferida a través de models CAD pot realitzar-se en tres etapes amb criteris contradictoris que deuen ser equilibrats per a arribar a la millor estratègia de modelatge. La investigació ha inclòs el desenvolupament de un mètode de validació que demostra que las rúbriques son dispositius útils per a garantir una comunicació consistent de la intenció de disseny, i son fonamentals no només per a avaluar, però també per a comunicar les expectatives de l'instructor. En aquesta investigació s'examinà com definir clarament les qualitats de la intenció de disseny per a permetre una mes fàcil avaluació de un acoblament CAD. Per a totes les dimensions de la rúbrica, es va trobar mes concordança i correlació entre instructors que no pas entre instructors i estudiants. Existeix una correlació moderada/fort entre els instructors per a les dimensions de la validesa, completesa, concisió i claredat, mentre que existeix una lleugera correlació per a les dimensions de consistència i intenció del disseny. En segon lloc, les rúbriques també poden ser descrites com estàtiques o dinàmiques. Les rúbriques estàtiques, existeixen sòls en paper, no proporcionen retroalimentació immediata a l'educand. Les rúbriques dinàmiques realitzen càlculs que proporcionen observacions de avaluació immediates al usuari. A mes, poden adaptar-se a situacions específiques dependent de la capacitat de l'usuari. Les rúbriques electròniques son ideals per a rúbriques dinàmiques, i permeten l'ús i desenvolupament de rúbriques adaptatives i adaptables, como es descriu a continuació. En tercer lloc, les rúbriques deuen ser adaptables, el que deuria ferles fàcilment comprensibles i fàcils d'usar, i adaptatives. Les rúbriques d'avaluació se usen quant un expert determina el progrés pedagògic de un educand, mentre que les rúbriques formatives son fetes servir per els propis estudiants, per a traçar el seu progrés i identificar les deficiències escolars para a les que necessiten suport. Les rúbriques es deuen refinar i millorar de forma continuada, en un procés iteratiu i col·laboratori, fins que se arriba a un acord satisfactori, tant entre avaluadors como entre avaluadors i alumnes. Por això, es desenvoluparen mapes de assercions que il·lustren el mode en que la estratègia de expansió-contracció adapta les rúbriques al progres del aprenent de CAD, a la vegada que ajuden a comprendre les diferents dimensions de la rúbrica. Basant-se en els experiments amb les rúbriques de acoblaments, es evident que les xicotetes diferencies entre els instructors suggereixen que la rúbrica de acoblaments proposta es lo suficientment sofisticada com per a proporcionar una avaluació acumulativa imparcial del acompliment de l'alumne. En conseqüència, es pot afirmar amb confiança que els avaluadors poden usar-se indistintament sense sacrificar la precisió. No obstant, la rúbrica de acoblaments posseeix una eficàcia finita per a produir una autoavaluació formativa de les habilitats de acoblament CAD per a nous alumnes. / Otey, JM. (2017). A Contribution to Conveying Quality Criteria in Mechanical CAD Models and Assemblies through Rubrics and Comprehensive Design Intent Quantification [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/94627 / TESIS

Teams of design engineers are increasingly working as members of virtual teams, or teams whose members are distributed geographically and communicate mostly through electronic means. In addition, emerging multi-user (MU) applications engage complementary teams in synchronous design activities. These new MU tools are changing the way engineers work together. Together, these factors have created a new and interesting environment in which engineering design teams must function. The work presented here lays out two major themes that teams and their managers can effectively apply to organizing and managing MU teams: 1) teams can maximize their potential productivity by determining the optimal number of teammates for a given modeling effort and by implementing a profile and team formation system based on the principle of optimizing complementary team member characteristics; and 2) to minimize process losses, teams can implement effective strategies for working in a MU and/or virtual setting and they can use novel new MU tools that address portions of the product development process that have previously not been addressed with such tools. It is my hope that these contributions can enable greater effectiveness and productivity among virtual engineering design teams as they strive to remedy many of the most pressing and dire issues facing humanity. By improving the way we work together, we can increase our ability to bless all of God's children.

The popularity of field-programmable gate arrays (FPGA) has grown in recent years due to their potential performance advantages over sequential software, and as a prototyping platform for application-specific integrated circuits (ASIC). Vendors such as Xilinx offer automated tool suites that can be used to program FPGAs based on a RTL description. These tool suites are sufficient forgeneral users, but they usually don't provide the opportunity to integrate custom computer-aideddesign (CAD) tools into the regular design flow. Xilinx first offered this capability in their ISE tool suite with the Xilinx Design Language (XDL). Using XDL, a Xilinx design could be extracted from the regular CAD flow, run through an external tool, and injected back into the flow. Research tools targeting commercial FPGAs have most commonly been based on XDL. Vivado (Xilinx's newest tool suite) no longer supports XDL, preventing similar tools from being created for next-generation devices. Instead, Vivado includes a Tcl interface that exposes Xilinx's internal design and device data structures. Considerable challenges still remain to users attempting to leverage this Tcl interface to develop external CAD tools. This thesis presents the Vivado Design Interface (VDI), a set of file formats and Tcl functions that address the challenges of exporting and importing designs to and from Vivado. To demonstrate its use, VDI has been integrated with RapidSmith2, an external FPGA CAD framework. To the best of our knowledge this work is the first successful attempt to provide an opensource tool-flow that can export designs from Vivado, manipulate them with external CAD tools, and re-import an equivalent representation back into Vivado.

OBJECTIVES: Evaluate the mechanical properties of commercial digital denture base materials. Materials: The materials used were Lucitone 199 denture base disc (Dentsply Sirona), AvaDent denture base puck (AvaDent), KeyMill denture base disc (Keystone), Lucitone digital print denture base resin (Dentsply Sirona), Formlabs denture base resin (Formlabs), and Dentca denture base resin II (Dentca). METHODS: For each material, 60 bar-shaped specimens were prepared for flexural testing, which were divided into 5 groups including control, fatigue, thermocycling, and repairing using 2 types of materials. 24 square-shaped specimens were included in the bond testing, bonded to tooth and composite resin. Additionally, 48 square-shaped specimens were fabricated for the color stability testing, against UV light and staining and washing solutions. The flexural strength and modulus were calculated through 3-point bend test. Bond strength was determined using shear bond test. Color coordinates were recorded in the CIE L*a*b* system using an X-Rite Ci7600 spectrophotometer. Color differences relative to the baseline (∆E^*) were obtained. Data were analyzed using one-way ANOVA followed by Tukey’s HSD test (α=0.05). RESULTS: Milled materials showed higher flexural strength than printed materials. Fatigue and thermocycling led to a decrease in the flexural strength of both group materials. Repaired groups showed flexural strength of about 30.67% and 32.80% of its original strength, in milled and printed materials respectively. However, the flexural strength of the printed materials was affected by the type of the repair material, composite resin gave higher values compared with acrylic. Printed materials exhibited superior bond strength to tooth and composite resin than milled materials. The color change under UV light was clinically acceptable. The color change after immersion in staining and washing solutions in milled groups was less noticeable than in the printed group. Thermocycling treatment made the color change more noticeable in both milled and printed groups. CONCLUSION: Milled denture materials exhibited higher flexural properties than printed denture materials. Printed materials exhibited higher shear bond to tooth and composite resin. The color stability of milled materials with staining and washing solutions treatment was better than the printed groups, whereas the color stability of milled and printed materials exposed to UV light was clinically acceptable. / 2023-08-03T00:00:00Z

The master’s thesis is aimed at creation of project documentation used in power engineering, specifically the creation of schemes in the field of secondary technology. It deals with the basics of marking used by distribution system operators in the Czech Republic, the levels of documentation necessary for the construction or reconstruction of the electrical equipment itself. The aim of this master’s thesis is to design the switchboard with two design solutions using two different types of software. Used software will be Autocad LT as a representative of the CAD system and Ruplan EVU as CAE software. Based on the experience gained in designing and pre-defined aspects, at the end of thesis determine software that is more suited to designing.