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Casting as a manufacturing process to make complex shapes of metal materials in mass production may experience many different defects such as porosity and incomplete filling. How to improve the casting quality becomes important. Gating/riser system design is critical to improving casting quality. The objective of the research presented in this thesis is to optimize gating/riser systems based on CAD and simulation technology with the goal of improving casting quality such as reducing incomplete filling area, decreasing large porosity and increasing yield. Therefore in the thesis, an optimization framework is presented based on CAD and simulation technology. Given a CAD model of part design and after converted to a casting model, it is the first step to evaluate castability of the casting design. Then the runner and risers are represented parametrically, and CAD models generated by varying parameters can be used in the simulation. After analyzing simulation results, the gating/riser system design is optimized to improve casting quality. In the thesis, one engine block is used to verify the effectiveness of the optimization method. Compared with the initial design, it is found that the optimized casting design can decrease porosity around 18% while the yield increases 16%.

O trabalho tem por objetivo definir um modelo de dados adequado à representação de sólidos e implementar um núcleo de modelagem geométrica para validar este modelo. Foi adotada a abordagem semântica Abstração de Dados para a representação formal do modelo geométrico. Os objetos são modelados utilizando operações de combinação e transformação geométrica. Foram adotadas as formas de representação interna por OCTREE, que define explicitamente as porções do espaço ocupadas pelos objetos, e por uma árvore CSG que mantém a descrição estruturada dos objetos segundo o processo construtivo. São apresentados os algoritmos para as operações de manipulação (combinação e transformação geométrica) e de exibição através de vistas ortográficas e de seções planas, bem como operações de consulta às propriedades dos objetos. / The goal of this work is to define a data model suitable for representing solids and to implement a solids modelling kernel. It, was used the Data Abstraction semantic model for representing the geometric model. The objects are modeled through set operations and geometric transformations. It was used two schemas of solids representations: OCTREE, which explicitly define the space occupied by objects, and CSG that is used to keep a structural description of objects according to the construction process. The algorithms for solids manipulation (set operations and geometric transformations) and the display generation through orthographic views and plane sections are presented as well as query operations over the objects properties.

<p>Trots att människor intresserat sig för moral och etik sedan antikens Grekland så verkar vi inte kommit närmare konsensus i en enda fråga. Förklaringen till detta kan vara att moral är subjektivt. En teori som stödjer detta subjektiva synsätt är CAD-teorin (Community, Autonomy & Divinity). Den säger att vissa känslor är kopplade till olika typer av moraliska brott, och att vi använder moralen som ett sätt att förklara dessa känslor. Enligt teorin så finns det tre stycken moraliska ”system”. Dessa är: individens etik, samhällets etik och den gudomliga etiken. CAD-teorin antar att tre stycken emotioner uppstår i oss när någon annan utför ett moraliskt brott mot något av dessa tre system. Dessa tre känslor är ilska, förakt och äckel. I ett försök att replikera tidigare studier så fick deltagarna i en enkät avgöra vilken känsla ett antal situationer gav upphov till, och sedan klassificera vilken typ av moraliskt brott som begåtts i dem. Dessutom undersöktes om CAD-teorin är tillämpbar på situationer som baserats på det som inom spelteorin kallas för utbyte och koordination. Hypotesen där var att ilska skulle uppstå när endast deltagaren höll överenskommelsen, samt att skam och skuld skulle uppstå när deltagaren bröt mot den. Resultaten stämde med hypoteserna i sammanlagt 24 av 39 fall. Kulturella, samt vissa språkliga, faktorer kan ha varit det som påverkade resultaten mest.</p>

<p>This report summarize a simple and efficient way to convert 2D into 3D designs. It explains the benefits of a 3D design compared with 2D, and how those benefits may be used.</p><p>It will also give the reader a presentation of the company Clean Air Technologies, which for the most part constructs cleaning facilities for power plants. How to create 3D-libraries for some of those facilities will be introduced in this composition.</p><p>The collaboration with Clean Air Technologies has resulted in several 3D animated movies and rendered images. This has increased the quality of the companies offer presentations, which has made it easier for the prospective customer to get an improved overall image of the power plant design.</p>

<p>This report is about the issue with decreasing production rate mainly caused by failuresrelated to the multiswitch. The multiswitch is a machine at Gefleortens Mejeriföreningwhich has the function of distributing milk cartons from one incoming track into fiveoutgoing tracks. Milk cartons who gets stuck and there by causes the production to stop,is the mainly problem with this construction</p><p>The purpose with this report is to understand the causing factors and make suggestions which can help solving these factors. By analyzing the machine during production, having contact with different suppliers, searching internet for information, 3d-cad drawings and the complementary with personal experiences, this machine has  been evaluated and as a result of this new problem has come to be known.</p><p>The discovered problems was analyzed and resulted in new suggestions for alternative options. Later the most functional results was chosen and put as a suggestion for the new model.</p><p>A new machine built with the suggestions from this report assures to be well adapted to the environment at Gefleortens Mejeriföreing and the problems it causes.</p>

We contribute a quantitative and systematic model to capture etch non-uniformity in deep reactive ion etch of microelectromechanical systems (MEMS) devices. Deep reactive ion etch is commonly used in MEMS fabrication where high-aspect ratio features are to be produced in silicon. It is typical for many supposedly identical devices, perhaps of diameter 10 mm, to be etched simultaneously into one silicon wafer of diameter 150 mm. Etch non-uniformity depends on uneven distributions of ion and neutral species at the wafer level, and on local consumption of those species at the device, or die, level. An ion–neutral synergism model is constructed from data obtained from etching several layouts of differing pattern opening densities. Such a model is used to predict wafer-level variation with an r.m.s. error below 3%. This model is combined with a die-level model, which we have reported previously, on a MEMS layout. The two-level model is shown to enable prediction of both within-die and wafer-scale etch rate variation for arbitrary wafer loadings. / Singapore-MIT Alliance (SMA)

The current well planning practice is usually done section by section with limited help of some knowledge-based tools. This thesis presents an integrated approach and a software prototype developed for well planning. It considers the geological input, i.e. pore pressure, over burden etc., to generate a step by step interactive drilling plan. The implemented well planning stages include the casing setting depth, casing and hole size determination, casing selection and then drill string design and modeling. The system is integrated with a Computer Aided Design (CAD) system for generating three-dimensional parametric model. The conceptual design and CAD modeling system are integrated in such a way that any changes in the design will be reflected to the CAD model. Such intelligent CAD design practice is new in the drilling industry. An Operational Parameters module is also attached with the system to predict the drilling coefficients by using offset well data and determine the optimum weight on bit, and the drill string rotation that minimizes drilling cost per foot for a single bit run. Based on this approach, an integrated well planning system can be fully developed and it will be very useful for the decision making of drilling companies.

Trots att människor intresserat sig för moral och etik sedan antikens Grekland så verkar vi inte kommit närmare konsensus i en enda fråga. Förklaringen till detta kan vara att moral är subjektivt. En teori som stödjer detta subjektiva synsätt är CAD-teorin (Community, Autonomy &amp; Divinity). Den säger att vissa känslor är kopplade till olika typer av moraliska brott, och att vi använder moralen som ett sätt att förklara dessa känslor. Enligt teorin så finns det tre stycken moraliska ”system”. Dessa är: individens etik, samhällets etik och den gudomliga etiken. CAD-teorin antar att tre stycken emotioner uppstår i oss när någon annan utför ett moraliskt brott mot något av dessa tre system. Dessa tre känslor är ilska, förakt och äckel. I ett försök att replikera tidigare studier så fick deltagarna i en enkät avgöra vilken känsla ett antal situationer gav upphov till, och sedan klassificera vilken typ av moraliskt brott som begåtts i dem. Dessutom undersöktes om CAD-teorin är tillämpbar på situationer som baserats på det som inom spelteorin kallas för utbyte och koordination. Hypotesen där var att ilska skulle uppstå när endast deltagaren höll överenskommelsen, samt att skam och skuld skulle uppstå när deltagaren bröt mot den. Resultaten stämde med hypoteserna i sammanlagt 24 av 39 fall. Kulturella, samt vissa språkliga, faktorer kan ha varit det som påverkade resultaten mest.