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A comparison is made between octrees, which are regular decompositions of volumes, and new, irregular decompositions called R-trees. This comparison is made within the context of the volume intersection problems that might be associated with an automatic inspection system. The results show that the irregular decomposition is independent of object position and can provide a more space efficient encoding for certain shapes. However, detecting intersections between R-trees requires an algorithm of greater complexity due to the irregularity of the decomposition. Algorithms are given for obtaining tree decompositions from a hierarchic relational model of a volume. Among these algorithms is a procedure for finding the minimal enclosing rectangular parallelepiped of a boundary representation, and a generalization of the point-in-polygon algorithm to boundaries on curved surfaces. Both of these algorithms have computation times that are proportional to the total number of components of the boundary's representation. / Master of Science

The N-heterocyclic carbene (NHCs) based pincer ligands field is still in its infancy after decades. They are known for their applications in organocatalysis, coordinating with transition metals and p-block elements, catalysis, and material chemistry. Among all NHCs, CCC-NHC-based on late-transition metal complexes were first developed by our group in 2005 with a unique metalation/transmetalation strategy. Our group also designed the chiral version of these CCC-NHC ligands to synthesize its metal complexes. However, their asymmetric catalytic applications were unknown. Wanting to expand on this work, we first successfully synthesized achiral CCC-NHC pincer complexes and their new catalytic application, as it is economically cheaper than directly working on developing a chiral version for catalysis. Then, different chiral CCC-NHC salts were synthesized based on different chiral arms and N-substituents on NHCs to modify their steric hindrance and electronic structure properties. These precursors were used for their enantioselective application in nucleophilic catalysis. In Chapter II, we will discuss the synthesis of the CCC-NHC pincer Ir (III) dimer complex and its first catalytic application in C−H functionalization of N-methylindoles with alpha-aryl-alpha-diazoacetates at the C-3. The best reaction conditions involve a combination of catalysts and substrates in a specific order. It resulted in the activation of the C-H bond with the formation of a new C-C bond to generate alpha-aryl-alpha-indolyl acetates with more than 99% conversion at room temperature without requiring any additives. The substrate scope and limitations of N-methyl indoles and diazoacetates were also explored. Chapter III will focus on a new modified synthetic route to synthesize and characterize chiral CCC-NHC chloride salts in a shorter synthetic route than the known one. The metalation/transmetalation of chiral CCC-NHC ligands with late transition metals and the initial attempt in asymmetric catalysis will be discussed in Chapter IV. Chapter, V, demonstrated nucleophilic catalysis of CCC-NHC precursors in benzoin condensation of aldehyde. The study started with the evaluation of fifteen different achiral bis-CCC-NHC salts based on triazole, imidazole, and benzimidazole. Further studies with chiral CCC-NHC salts also resulted in more than 99% conversion and 99% ee in benzoin products. The substrate scope of benzaldehyde with different substituents was also explored

This report presents a comprehensive investigation into the accuracy and stability of Finite Difference Methods (FDM) when applied to the acoustic wave equation. The analysis focuses on comparing the classical 2nd order FDM with highly-accurate computational stencil of order 2p = 2,4 and 6 with Summation-by-Parts (SBP) and Simultaneous Approximation Term (SAT) technique of the Finite Difference Method. The objective of the study is to investigate complex numerical techniques that contributes to highly-accurate and stable solutions to many hyperbolic PDEs.  The report starts by introducing the governing problem and studies its well-posedness to ensure stable and unique solutions of the governing equations. It continues with basic introduction to the classic spatial discretization of the FDM and introduces the SBP-SAT implementation of the method. The governing equations are rewritten as a semi-discrete problem, such that it can be written as a system of ordinary differential equations (ODEs) only dependent on the temporal evolution. This system can be solved with classic Runge-Kutta methods to ensure robust and accurate time-stepping schemes.  The results show that the implementation of the higher-order SBP-SAT Finite Difference Method provides highly accurate solutions of the acoustic wave equation compared to the classic FDM. The results also show that the method provides stable solutions with no visible oscillations (dispersion), which can be a challenge for higher order methods. Overall, this paper contributes with valuable insights into the analysis of accuracy and stability in finite difference methods for acoustic wave equation.

Opus 25 is a collection of compositions which I created between September 1995 and April 1997. Instrumentation varies; there are works for choirs, chamber ensembles, solo voice, solo harp, solo piano, and orchestra. All the works included in this collection have been performed at some point during this same period, and recordings of these performances can be found on the accompanying cassette.

Opus 25 is a collection of compositions which I created between September 1995 and April 1997. Instrumentation varies; there are works for choirs, chamber ensembles, solo voice, solo harp, solo piano, and orchestra. All the works included in this collection have been performed at some point during this same period, and recordings of these performances can be found on the accompanying cassette. / Arts, Faculty of / Music, School of / Includes 1 sound cassette / Graduate

Résumé : En dépit des nombreuses recherches pour réduire le coût d'inspection des pièces à l'aide d'outils numériques, l'inspection de pièces souples demeure un défi. La raison est que les pièces souples peuvent prendre à l'état libre une forme substantiellement différente de leur géométrie nominale. Il en résulte que l'inspection de ce type de pièces nécessite des outils dédiés et coûteux, comme un gabarit d'inspection. Cette thèse détaille les défis associés au contrôle de ces pièces, pour proposer ensuite une méthode permettant l'inspection à l'état libre de pièces souples ayant une spécification limitant les forces de montage. L'approche proposée combine la méthode par éléments finis, les méthodes de traitement d'images ainsi que les démarches du domaine de l'optimisation. Essentiellement, la méthode proposée transpose (maps) le nuage de points représentant la pièce à l'état libre dans une configuration correspondant à sa géométrie installée sur son gabarit d'inspection. La méthode n'exige pas la conversion du nuage de points en modèle d'éléments finis, et veille à ce que les forces de montage ne dépassent pas leurs limites spécifiées, tout en tolérant des incertitudes dans la position des points de fixation simulant l'interface de montage. Ceci est accompli par le biais d'une optimisation par contrainte des déplacements des points de fixation. La contrainte de l'optimisation limite l'étendue des valeurs des forces de montage. La performance de la méthode d'inspection numérique proposée est évaluée à partir de cas d'études simulés, ainsi qu'à partir de deux pièces réelles du secteur de l'aéronautique. // Abstract : Despite extensive research to reduce the cost of inspection of parts using computational tools, inspection of compliant parts remains a challenge. The reason is that in a free-state, compliant parts can take on different shapes compared to their design model. It follows that the inspection of such parts requires dedicated and expensive inspectionfixtures. This thesis details the challenges associated with the inspection of these partsto then propose a fixetureless inspection method for compliant parts for which theirfunctional requirements mandate to limit the restraining forces imposed during assembly. The proposed approach combines the finite element method, image processing andoptimization techniques. Essentially, the proposed method maps the point cloud, representing the part in a free-state, to a configuration corresponding to its shape mounted onto its inspection fixture. The method does not necessitate the conversion of the point cloud into a finite element model, ensures that restraining forces do not exceed their specified limits, and accepts uncertainties in the position of features simulating the mounting interface. This is done through an constrained optimization on the displacements of the fixing points. The optimization constraint bounds the restraining forces values. The performance of the proposed computational inspection method is evaluated on simulated case studies, as well as on two aeronautics workpiece.

Cette thèse étudie l'option "zéro" dans l'analyse conjointe. Cette dernière s'assimile à un non choix des scénarios présentés lors d'enquêtes. Ce non choix est représenté par deux concepts distincts qui sont le refus et le conflit. Le premier concerne l'inappréciation des produits, alors que le second traite de l'incertitude dans les préférences et les choix. Une nouvelle modélisation économétrique de ce non choix est proposée dans ce travail, en supposant un mélange de spécification des comparaisons d'utilité et des seuils de réaction. Ce mélange permet de n'associer des utilités qu'aux produits, et de les comparer aux seuils de l'option "zéro". Ces comparaisons déterminent, ainsi, les situations de non choix, sans pour autant postuler une utilité au refus et au conflit.<br />Une étude sur le marché de la Vidéo à la Demande y est réalisée. Les résultats sont obtenus en utilisant l'approche bayésienne sur les modèles individuels et le maximum de vraisemblance sur le modèle agrégé. Les estimations sont cohérentes avec la réalité et la significativité des valeurs du refus et du conflit démontre leur importance dans la prise de décision.

本研究主要探討汽車零組件廠商之國際化發展歷程、國際化進入模式選擇以及廠商核心資源能力對其國際化策略之影響。首先藉由文獻探討瞭解企業國際化、核心能力、成長策略及策略九說等相關議題，接著透過實地訪談及次級資料蒐集對研究個案的國際化發展歷程作一回顧，最後分別由國際化理論、資源基礎說及策略九說的觀點對個案的國際化發展歷程及經營策略作歸納整理與分析，並提出本研究之結論。 台灣產業發展以製造業為主體，特別是資通訊產品、機械、自行車等產業在世界上均取得良好的成績。然而面對新興發展國家的急起直追，台灣製造業如何繼續維持本身的競爭優勢，從過去強調製造技術的專精，力求跨入設計、行銷等領域，走向微笑曲線的兩端，成為未來台灣廠商的新挑戰。以資訊產業為例，台灣廠商多專精於通用規格產品製造，藉由大量生產降低成本，常採取的成長策略為極力擴張產能，設法切入產業全球供應鏈成為其中一環。然而相對於資通訊、自行車產品，AM汽車零組件講究少量多樣，在產品生產與企業經營上亦有一定的困難度，台灣廠商如何能在AM車體碰撞零組件市場居世界領導地位，其經營歷程與成長策略究竟為何？立足於現今的基礎上，台灣汽車零組件產業下一階段的成長又應往那個方向進行？這是本研究想探討的議題。 目前台灣約供應全球85％-90％之汽車AM碰撞零組件，本研究選擇台灣AM碰撞件業者中規模最大，亦是全球領導廠商之東陽集團為研究個案，該公司在天下雜誌2007年國內製造業行業別（汽車及其零件）排名中名列第6，營收規模領先帝寶、堤維西等同業，年營收淨額新台幣165.8億元。研究結論簡述如下： 一、強大的模具開發能力、完善的集貨網路、少量多樣彈性生產的管理能力，是台灣AM碰撞件廠商國際化發展成功的重要因素。 二、AM汽車碰撞件廠商國際化發展過程中，應視本身資源能力及國際市場條件，彈性選擇最適的國際化發展模式。 三、AM碰撞件廠商可透過整併競爭對手、增加顧客價值、累積資源能力等方式提昇產業競爭地位，逐步取得市場主導權。 四、AM碰撞件業者可透過降低內部生產成本與外部資源取得成本，提高經營效率，增強市場競爭力。 五、台灣AM碰撞件廠商未來發展應掌握發展潛力雄厚的新興市場，並積極切入國際大車廠OEM零件供應鏈。 / Taiwanese companies produce 85%-90% of the After Market (AM) auto crash parts in the world. While most other countries’ auto parts export is substantially composed of OEM parts, Taiwan is one of the few countries which mainly exports AM auto parts in the world. With the limited market size in Taiwan, Taiwanese auto parts industry has to seek out the global market for potential markets. As a result, more than 80% of Taiwan-produced auto parts are exported each year, of which more than 80% are for AM use. The purpose of this research is to understand the internationalization of AM auto parts industry in Taiwan. The research consists of four aspects: (I) the characters of auto parts industry; (II) the internationalization of business; (III) the core competency of business; (IV) the business growth strategy. The research chose the leading AM auto parts manufacturer in Taiwan, the Tong Yang Group (TYG) as the study case. Through primary data collection such as in-depth interview and secondary data collection from other researches and publications, the research concludes as followed: 1.Mold development ability, broad sourcing network, and flexible production management are the key success factors of the internationalization of Taiwanese AM auto crash parts manufacturer. 2.During the process of internationalization, the most suitable entry model should be chosen based on the AM auto parts manufacturer’s own resources, capabilities and the market conditions. 3.AM crash parts manufacturer can raise their competitive advantage and gain market dominance by: Merger & Acquisition (M&A), increasing customer perceived value, and accumulating resources and capabilities. 4.AM crash parts manufacturer can strengthen competitiveness and increase efficiency by reduce both internal production costs and external sourcing costs. 5.Taiwanese AM auto parts manufacturers should grasp the emerging markets with great potential, and manage to penetrate the OEM parts supply chain of leading global auto manufacturers.

Advances in numerical optimization have raised the possibility that efficient and novel aircraft configurations may be ``discovered'' by an algorithm. To begin exploring this possibility, a fast and robust set of tools for aerodynamic shape optimization is developed. Parameterization and mesh-movement are integrated to accommodate large changes in the geometry. This integrated approach uses a coarse B-spline control grid to represent the geometry and move the computational mesh; consequently, the mesh-movement algorithm is two to three orders faster than a node-based linear elasticity approach, without compromising mesh quality. Aerodynamic analysis is performed using a flow solver for the Euler equations. The governing equations are discretized using summation-by-parts finite-difference operators and simultaneous approximation terms, which permit nonsmooth mesh continuity at block interfaces. The discretization results in a set of nonlinear algebraic equations, which are solved using an efficient parallel Newton-Krylov-Schur strategy. A gradient-based optimization algorithm is adopted. The gradient is evaluated using adjoint variables for the flow and mesh equations in a sequential approach. The flow adjoint equations are solved using a novel variant of the Krylov solver GCROT. This variant of GCROT is flexible to take advantage of non-stationary preconditioners and is shown to outperform restarted flexible GMRES. The aerodynamic optimizer is applied to several studies of induced-drag minimization. An elliptical lift distribution is recovered by varying spanwise twist, thereby validating the algorithm. Planform optimization based on the Euler equations produces a nonelliptical lift distribution, in contrast with the predictions of lifting-line theory. A study of spanwise vertical shape optimization confirms that a winglet-up configuration is more efficient than a winglet-down configuration. A split-tip geometry is used to explore nonlinear wake-wing interactions: the optimized split-tip demonstrates a significant reduction in induced drag relative to a single-tip wing. Finally, the optimal spanwise loading for a box-wing configuration is investigated.