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Caractérisation du refroidissement par jet liquide impactant une plaque métallique à haute température : Iinfluence de la composition du fluide sur le flux extrait / Characterization of a cooling fluid impinging a metal plate at high temperatures : Influence of fluid’s composition on the cooling fluxOuattara, Aboubacar 15 June 2009 (has links)
Dans le cadre de cette thèse, il s’agit de voir l’influence de la composition du fluide sur le flux extrait. En effet l’eau utilisée pour le refroidissement des bandes d’acier en sortie de laminoir est recyclée et est potentiellement polluée par des résidus d’huile provenant de la lubrification des cylindres de laminoir. Nous avons conçu un dispositif expérimental original qui consiste à chauffer sur sa face supérieure un disque en Nickel à des températures de l’ordre de 600°C grâce à un dispositif d’induction électromagnétique et ensuite à le refroidir par un jet impactant. La face non refroidie est accessible à une mesure par thermographie infrarouge. Ces conditions de mesures nous ont permis d’estimer le flux extrait sur la face supérieure (lieu du refroidissement) à partir des mesures de température par thermographie infrarouge sur la face inférieure à l’aide d’un modèle de conduction inverse spécifiquement développé. Les résultats ont permis de montrer que la présence d’huile, si elle dégrade le flux maximal extrait dans certaines zones, conduit à une cinétique globale du refroidissement supérieure à celle de l’eau pure. / In this work, we are interested in the influence of the fluid’s composition on the cooling flux. In fact water used for cooling is recycled and can be potentially polluted by residues oil from the lubrication of rolling cylinder. We have designed an original experimental device which consists of heating a Nickel disk on its upper face at temperatures of 600°C through electromagnetic induction and then cooling it by jet impingement. The reverse face is available by infrared thermography measurements. These conditions allowed us to estimate the heat flux on the upper face (the cooling area) by infrared thermography measurements with a specific inverse heat conduction model. The results showed that the presence of oil, if it degrades the maximum cooling flux in some areas, led to a better overall cooling than that obtained with pure water.
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Schulter-TEP-Wechsel-Operationen mit der reversen Schulterprothese / Revision shoulder arthroplasty to reverse total shoulder prosthesisWerner, Birgit Simone January 2008 (has links) (PDF)
Im Zeitraum von Juni 2001 bis Februar 2005 wurden an der Orthopädischen Klinik König-Ludwig-Haus insgesamt 47 Revisionsoperationen unter Verwendung der reversen Endoprothese nach Grammont durchgeführt. Dabei handelte es sich um 31 Wechseloperationen nach fehlgeschlagener Frakturprothese und 14 Revisionen nach osteosynthetischer Versorgung. Zum Zeitpunkt der Operation lag das mittlere Lebensalter bei 66,8 Jahren. In 27 Fällen war die dominante Seite betroffen. Die Anzahl der Voroperationen betrug im Durchschnitt 1,96 (1-8). Die klinische und radiologische Kontrolluntersuchung erfolgte im Mittel 20,9 Monate postoperativ. Die Ergebnisse wurden anhand des Constant-Score erhoben. Zum Zeitpunkt der Nachuntersuchung zeigten sich 38% (18 Fälle) der Patienten mit dem Ergebnis der Operation sehr zufrieden und 53% (25 Fälle) zufrieden, alle Patienten würden den Eingriff erneut durchführen lassen. Der alters- und geschlechtsadaptierte Constant-Score betrug präoperativ 19% und verbesserte sich postoperativ auf 66%. Es wurde in allen Fällen eine deutliche Schmerzreduktion erzielt. Der aktive Bewegungsumfang und damit die Funktionalität der Schulter konnte deutlich gesteigert werden. Zum Zeitpunkt der Nachuntersuchung fanden sich in der radiologischen Untersuchung keine gelockerten Implantate. In sieben Fällen (14,9%) traten revisionsbedürftige Komplikationen auf. Hinsichtlich der vorausgehenden Versorgung ließen sich nach fehlgeschlagener Osteosynthese tendenziell bessere Ergebnisse erzielen als bei Wechseloperationen nach Frakturprothese. / From 2001 to 2005, a total of 47 shoulder replacement revisions using the reverse prosthesis were performed. 31 were revisions of failed fracture arthroplasties. The average age at time of the operation was 66.8 years, the average follow-up 20.9 months. The preoperative age- and gender-related Constant Score was 19% and improved to 66% postoperatively. Pain was relieved in every patient. 38% were very satisfied and 53% satisfied with the surgical outcome. There were seven complications in total.
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Simulating Realistic Ragdoll Behaviour In Physical Situations / Simulering av Realistiskt Ragdoll Beteende i Fysiska SituationerStenlund, Pontus January 2019 (has links)
When trying to make a game character come alive and add some sense of realism to a game, it can be done in multiple ways. Animating a 3D model is the commonly used one and it is usually done by hand. The artist moves the model's limbs bit by bit to make small animation clips that are then played in the game. This has a few drawbacks, it's time consuming and depending on what the character is doing in the game it won't always look accurate. Ragdolls can be used together with animations to help bring more realism to the model. Together with animation and colliders on the model limbs, it can simulate when the models limbs interact with objects on the screen. It can also simulate physical responses that happen. But some problems still remain that can't be solved by ragdolls and animation alone. One example is the foot position when a character walking up or down sloped terrain. The foot can clip through the terrain and destroy the sence realism, however ragdolls together with inverse kinematics can solve such problems.
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The Nash-Moser inverse function theorem and the isometric embedding problem in Riemannian geometry.January 1984 (has links)
Sung Wing-wah. / Bibliography: leaves 42-45 / Thesis (M.Ph.)--Chinese University of Hong Kong, 1984
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Numerical determination of potentials in conservative systems.January 1999 (has links)
Chan Yuet Tai. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (leaves 107-111). / Chapter 1 --- Introduction to Sturm-Liouville Problem --- p.1 / Chapter 1.1 --- What are inverse problems? --- p.1 / Chapter 1.2 --- Introductory background --- p.2 / Chapter 1.3 --- The Liouville transformation --- p.3 / Chapter 1.4 --- The Sturm-Liouville problem 一 A historical look --- p.4 / Chapter 1.5 --- Where Sturm-Liouville problems come from? --- p.6 / Chapter 1.6 --- Inverse problems of interest --- p.8 / Chapter 2 --- Reconstruction Method I --- p.10 / Chapter 2.1 --- Perturbative inversion --- p.10 / Chapter 2.1.1 --- Inversion problem via Fredholm integral equation --- p.10 / Chapter 2.1.2 --- Output least squares method for ill-posed integral equations --- p.15 / Chapter 2.1.3 --- Numerical experiments --- p.17 / Chapter 2.2 --- Total inversion --- p.38 / Chapter 2.3 --- Summary --- p.45 / Chapter 3 --- Reconstruction Method II --- p.46 / Chapter 3.1 --- Computation of q --- p.47 / Chapter 3.2 --- Computation of the Cauchy data --- p.48 / Chapter 3.2.1 --- Recovery of Cauchy data for K --- p.51 / Chapter 3.2.2 --- Numerical implementation for computation of the Cauchy data . --- p.51 / Chapter 3.3 --- Recovery of q from Cauchy data --- p.52 / Chapter 3.4 --- Iterative procedure --- p.53 / Chapter 3.5 --- Numerical experiments --- p.60 / Chapter 3.5.1 --- Eigenvalues without noised data --- p.64 / Chapter 3.5.2 --- Eigenvalues with noised data --- p.69 / Chapter 4 --- Appendices --- p.79 / Chapter A --- Tikhonov regularization --- p.79 / Chapter B --- Basic properties of the Sturm-Liouville operator --- p.80 / Chapter C --- Asymptotic formulas for the eigenvalues --- p.86 / Chapter C.1 --- Case 1: h ≠ ∞ and H ≠ ∞ --- p.87 / Chapter C.2 --- Case 2: h= ∞ and H ≠∞ --- p.90 / Chapter C.3 --- Case 3: h = ∞ and H = ∞ --- p.91 / Chapter D --- Completeness of the eigenvalues --- p.92 / Chapter E --- d'Alembert solution formula for the wave equation --- p.97 / Chapter E.1 --- "The homogeneous solution uH(x,t)" --- p.98 / Chapter E.2 --- "The particular solution up(x, t)" --- p.99 / Chapter E.3 --- "The standard d'Alembert solution u(x,t)" --- p.101 / Chapter E.4 --- Applications to our problem --- p.101 / Chapter F --- Runge-Kutta method for solving eigenvalue problems --- p.104 / Bibliography --- p.107
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Inverse problems: from conservative systems to open systems = 反問題 : 從守恆系統到開放系統. / 反問題 / Inverse problems: from conservative systems to open systems = Fan wen ti : cong shou heng xi tong dao kai fang xi tong. / Fan wen tiJanuary 1998 (has links)
Lee Wai Shing. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (leaves 129-130). / Text in English; abstract also in Chinese. / Lee Wai Shing. / Contents --- p.i / List of Figures --- p.v / Abstract --- p.vii / Acknowledgement --- p.ix / Chapter Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- What are inverse problems? --- p.1 / Chapter 1.2 --- Background of this research project --- p.2 / Chapter 1.3 --- Conservative systems and open systems -normal modes (NM's) vs quasi-normal modes (QNM's) --- p.3 / Chapter 1.4 --- Appetizer ´ؤ What our problems are like --- p.6 / Chapter 1.5 --- A brief overview of the following chapters --- p.7 / Chapter Chapter 2. --- Inversion of conservative systems- perturbative inversion --- p.9 / Chapter 2.1 --- Overview --- p.9 / Chapter 2.2 --- Way to introduce the additional information --- p.9 / Chapter 2.3 --- General Formalism --- p.11 / Chapter 2.4 --- Example --- p.15 / Chapter 2.5 --- Further examples --- p.19 / Chapter 2.6 --- Effects of noise --- p.23 / Chapter 2.7 --- Conclusion --- p.25 / Chapter Chapter 3. --- Inversion of conservative systems - total inversion --- p.26 / Chapter 3.1 --- Overview --- p.26 / Chapter 3.2 --- Asymptotic behaviour of the eigenfrequencies --- p.26 / Chapter 3.3 --- General formalism --- p.28 / Chapter 3.3.1 --- Evaluation of V(0) --- p.28 / Chapter 3.3.2 --- Squeezing the interval - evaluation of the potential at other positions --- p.32 / Chapter 3.4 --- Remarks --- p.36 / Chapter 3.5 --- Conclusion --- p.37 / Chapter Chapter 4. --- Theory of Quasi-normal Modes (QNM's) --- p.38 / Chapter 4.1 --- Overview --- p.38 / Chapter 4.2 --- What is a Quasi-normal Mode (QNM) system? --- p.38 / Chapter 4.3 --- Properties of QNM's in expectation --- p.40 / Chapter 4.4 --- General Formalism --- p.41 / Chapter 4.4.1 --- Construction of Green's function and the spectral represen- tation of the delta function --- p.42 / Chapter 4.4.2 --- The generalized norm --- p.45 / Chapter 4.4.3 --- Completeness of QNM's and its justification --- p.46 / Chapter 4.4.4 --- Different senses of completeness --- p.48 / Chapter 4.4.5 --- Eigenfunction expansions with QNM's 一 the two-component formalism --- p.49 / Chapter 4.4.6 --- Properties of the linear space Γ --- p.51 / Chapter 4.4.7 --- Klein-Gordon equation - The delta-potential system --- p.54 / Chapter 4.5 --- Studies of other QNM systems --- p.54 / Chapter 4.5.1 --- Wave equation - dielectric rod --- p.55 / Chapter 4.5.2 --- Wave equation ´ؤ string-mass system --- p.57 / Chapter 4.6 --- Summary --- p.58 / Chapter Chapter 5. --- Inversion of open systems- perturbative inversion --- p.59 / Chapter 5.1 --- Overview --- p.59 / Chapter 5.2 --- General Formalism --- p.59 / Chapter 5.3 --- Example 1. Klein-Gordon equation ´ؤ delta-potential system --- p.66 / Chapter 5.3.1 --- Model perturbations --- p.66 / Chapter 5.4 --- Example 2. Wave equation ´ؤ dielectric rod --- p.72 / Chapter 5.5 --- Example 3. Wave equation ´ؤ string-mass system --- p.76 / Chapter 5.5.1 --- Instability of the matrix [d] = [c]-1 upon truncation --- p.79 / Chapter 5.6 --- Large leakage regime and effects of noise --- p.81 / Chapter 5.7 --- Conclusion . . . --- p.84 / Chapter Chapter 6. --- Transition from open systems to conservative counterparts --- p.85 / Chapter 6.1 --- Overview --- p.85 / Chapter 6.2 --- Anticipations of what is going to happen --- p.86 / Chapter 6.3 --- Some computational experiments --- p.86 / Chapter 6.4 --- Reason of breakdown - An intrinsic error of physical systems --- p.87 / Chapter 6.4.1 --- Mathematical derivation of the breakdown behaviour --- p.90 / Chapter 6.4.2 --- Two verifications --- p.93 / Chapter 6.5 --- Another source of errors - An intrinsic error of practical computations --- p.95 / Chapter 6.5.1 --- Vindications --- p.96 / Chapter 6.5.2 --- Mathematical derivation of the breakdown --- p.98 / Chapter 6.6 --- Further sources of errors --- p.99 / Chapter 6.7 --- Dielectric rod --- p.100 / Chapter 6.8 --- String-mass system --- p.103 / Chapter 6.9 --- Conclusion --- p.105 / Chapter Chapter 7. --- A first step to Total Inversion of QNM systems? --- p.106 / Chapter 7.1 --- Overview --- p.106 / Chapter 7.2 --- Derivation for F(0) --- p.106 / Chapter 7.3 --- Example 一 delta potential system --- p.108 / Chapter Chapter 8. --- Conclusion --- p.111 / Chapter 8.1 --- A summary on what have been achieved --- p.111 / Chapter 8.2 --- Further directions to go --- p.111 / Appendix A. A note on notation --- p.113 / Appendix B. Asymptotic series of NM eigenvalues --- p.114 / Appendix C. Evaluation of functions related to RHS(x) --- p.117 / Appendix D. Asymptotic behaviour of the Green's function --- p.119 / Appendix E. Expansion coefficient an --- p.121 / Appendix F. Asymptotic behaviour of QNM eigenvalues --- p.123 / Appendix G. Properties of the inverse matrix [d] = [c]-1 --- p.125 / Appendix H. Matrix inverse through the LU decomposition method --- p.127 / Bibliography --- p.129
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Manipulation robotique à deux mains inspirée des aptitudes humaines / Dual-arm robotic manipulation inspired by human skillsTomic, Marija 04 July 2018 (has links)
Le nombre de robot humanoïde s’est accru ces dernières années pour pouvoir collaborer avec l’homme ou le remplacer dans des tâches fastidieuses. L’objectif de cette thèse est de transférer aux robots humanoïdes, des habilités ou compétences humaines, en particulier pour des mouvements impliquant une coordination entre les deux bras. Dans la première partie de la thèse, un processus de conversion d’un mouvement humain vers un mouvement de robot, dans un objectif d’imitation est proposé. Comme les humains possèdent beaucoup plus de degrés de liberté qu’un robot humanoïde, les mouvements identiques ne peuvent pas être produits, les caractéristiques(longueurs des corps) peuvent aussi être différentes. Notre processus de conversion prend en compte l’enregistrement des localisations de marqueurs attachés aux corps de l’humain et des articulations pour améliorer les processus d’imitation. La deuxième partie de la thèse vise à analyser les stratégies de génération du mouvement utilisées par l’homme. Les mouvements humains sont supposés optimaux et notre objectif est de trouver un critère à minimiser pendant les manipulations. Nous faisons l’hypothèse que ce critère est une combinaison de critères classiquement utilisés en robotique et nous recherchons les poids de chaque critère qui représente au mieux le mouvement humain. De cette façon, une approche de commande cinématique optimale peut ensuite être utilisée pour générer des mouvements du robot humanoïde. / The number of humanoid robots has increased in recent years to be able to collaborate with humans or replace them in tedious tasks. The objective of this thesis is to transfer to humanoid robots, skills or human competences, in particular for movements involving coordination between the two arms. In the first part of the thesis, a process of conversion from a human movement to a robot movement, with the aim of imitation is proposed. Since humans have much more freedom than a humanoid robot, identical movements cannot be produced, the characteristics (body lengths) canal so be different. Our conversion process takes into account the recording of marker locations attached to human bodies and joints to improve the imitation processes. The second part of the thesis aims at analyzing the strategies used by humans to generate movement. Human movements are assumed to be optimal and our goal is to find criteria minimized during manipulations. We hypothesize that this criterion is a combination of classical criteria used in robotics and we look for the weights of each criterion that best represents human movement. In this way, an optimal kinematic control approach can then be used to generate movements of the humanoid robot.
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Theoretical investigation of non-invasive methods to identify origins of cardiac arrhythmiasPerez Alday, Erick Andres January 2016 (has links)
Cardiac disease is one of the leading causes of death in the world, with an increase in cardiac arrhythmias in recent years. In addition, myocardial ischemia, which arises from the lack of blood in the cardiac tissue, can lead to cardiac arrhythmias and even sudden cardiac death. Cardiac arrhythmias, such as atrial fibrillation, are characterised by abnormal wave excitation and repolarization patterns in the myocardial tissue. These abnormal patterns are usually diagnosed through non-invasive electrical measurements on the surface of the body, i.e., the electrocardiogram (ECG). However, the most common lead configuration of the ECG, the 12-lead ECG, has its limitations in providing sufficient information to identify and locate the origin of cardiac arrhythmias. Therefore, there is an increasing need to develop novel methods to diagnose and find the origin of arrhythmic excitation, which will increase the efficacy of the treatment and diagnosis of cardiac arrhythmias. The objective of this research was to develop a family of multi-scale computational models of the human heart and thorax to simulate and investigate the effect of arrhythmic electrical activity in the heart on the electric and magnetic activities on the surface of the body. Based on these simulations, new theoretical algorithms were developed to non-invasively diagnose the origins of cardiac arrhythmias, such as the location of ectopic activities in the atria or ischemic regions within the ventricles, which are challenging to the clinician. These non-invasive diagnose methods were based on the implementation of multi-lead ECG systems, magnetocardiograms (MCGs) and electrocardiographic imaging.
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Some observations on numerical solutions of linear inverse problems.January 2004 (has links)
Hung Kin Ting. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 126-129). / Abstracts in English and Chinese. / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Inverse Problems --- p.1 / Chapter 1.2 --- Applications of Inverse Problems --- p.2 / Chapter 1.3 --- Least-squares Solutions --- p.4 / Chapter 1.4 --- Discrete Systems --- p.4 / Chapter 1.5 --- "Discretization, Regularization and Regularization Pa- rameters" --- p.5 / Chapter 1.6 --- Outline of the Thesis --- p.6 / Chapter 2 --- Some Basic Concepts and Mathematical Tools --- p.8 / Chapter 2.1 --- Singular Value Decomposition (SVD) --- p.8 / Chapter 2.2 --- Generalized Singular Value Decomposition (GSVD) --- p.13 / Chapter 2.3 --- White Noises --- p.16 / Chapter 3 --- Regularized Solutions --- p.18 / Chapter 3.1 --- Derivation of Regularized Solutions --- p.18 / Chapter 3.2 --- Discrete Picard Condition --- p.20 / Chapter 3.3 --- Relationship between Discrete Picard Condition and Regularized Solution --- p.21 / Chapter 3.4 --- Checking for the Discrete Picard Condition --- p.22 / Chapter 4 --- Different Discretization Approaches --- p.23 / Chapter 4.1 --- Problem 1 - Volterra Integral Equation of the First Kind --- p.25 / Chapter 4.2 --- Examples of Problem 1 --- p.30 / Chapter 4.3 --- Problem 2 - Fredholm Integral Equation of the First Kind --- p.49 / Chapter 4.4 --- Examples of Problem 2 --- p.53 / Chapter 4.5 --- Conclusion --- p.57 / Chapter 5 --- Effect of Different Kinds of Observation Data and Differential Operators on Accuracy --- p.59 / Chapter 5.1 --- Pointwise Observation Data --- p.60 / Chapter 5.2 --- Pointwise Observation Data of Heat Fluxes at the Boundary --- p.69 / Chapter 5.3 --- Observation Data with Heat Fluxes --- p.80 / Chapter 5.4 --- Conclusion --- p.89 / Chapter 6 --- L-curve --- p.90 / Chapter 6.1 --- Properties of L-curve --- p.93 / Chapter 6.2 --- L-curve in Log-Log Scale --- p.100 / Chapter 6.3 --- Disadvantages of the L-curve Method --- p.100 / Chapter 7 --- Algorithms of Finding the Corner of L-curve --- p.105 / Chapter 7.1 --- Cubic Spline Curve Fitting --- p.105 / Chapter 7.2 --- Conic Section Fitting --- p.106 / Chapter 7.3 --- Triangle Method --- p.109 / Chapter 8 --- Implementation of the L-curve Method --- p.111 / Chapter 8.1 --- Our Algorithm --- p.111 / Chapter 8.2 --- Numerical Experiments --- p.112 / Chapter 8.3 --- Conclusion --- p.124 / Bibliography --- p.126
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Resultados matemáticos sobre o método de espalhamento inverso. / Mathematical results about the method of inverse scattering.Helena Maria Avila de Castro 26 April 1984 (has links)
Neste trabalho são apresentados alguns resultados matemáticos relevantes para a aplicação do método de espalhamento inverso à resolução de uma classe de equações de evolução não-lineares. É demonstrada a propriedade isoespectral para certas famílias de operadores lineares não auto-adjuntos. Esta propriedade tem um papel central na aplicação do método acima a equações de evolução não-lineares de interesse físico, tais como a equação de sine-Gordon e a equação de Schrödinger não-linear. É feito também, uma teoria de espalhamento inverso rigorosa para sistemas do tipo Zakharov-Shabat, o que inclui uma análise qualitativa do espectro de operadores deste tipo. / This Thesis presents some mathematical results relevant in applications of the inverse scattering transform to the solution of a class of non-linear evolution equations. First, it is shown that certain families of non-selfadjoint linear operators have the isospectral property, which is fundamental for the above applications. These families include various operators related to no-linear equations of great physical interest, such as the sine-Gordon and the non-linear Schrödinger equations. In the sequel, a rigorous inverse scattering theory, including a qualitative spectral analysis, is developed for systems of Zakharov-Shabat type.
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