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Lashore, Michael. "Mathematical Model Validation of a Center of Gravity Measuring Platform Using Experimental Tests and FEA." DigitalCommons@CalPoly, 2015. https://digitalcommons.calpoly.edu/theses/1467.
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This thesis sets out to derive an analytical model for a center of gravity (CG) measuring platform and examines its validity through experimental testing and Finite Element Modeling. The method uses a two-stage platform tilting process to first locate the planar CG coordinates and then find the third CG coordinate normal to the platform. An uncertainty model of the measuring platform was also developed, both CG and uncertainty models were implemented in the form of a MATLAB code. A load cell sizing task was also added to the code to assist the Integration Engineers at Jet Propulsion Laboratory in selecting load cells to design their own version of the CG Platform. The constructed CG Platform for this project used an array of six strain gauges, four C2A-06-062LT-120 Tee Rosettes and two C2A-06-031WW-120 Stacked Rosettes. They were bonded onto the legs of three truss shaped bipods. Results from the Platform Tilting Tests could not be used to validate the CG model as the measured CG and weight values found from the experimental tests contained a considerable amount of error. The errors in the Platform Tilting Tests are believed to stem from the initial errors observed during the bipod rod and strain gauge calibration tests. As an alternative, an FE model of the CG measuring platform was created as another means of validation. The math model of the CG measuring platform was successfully validated by showing that there was less than a 0.01% different between the bipod loads predicted from the MATLAB code and the FE model. Using the FEM generated loads as inputs into the CG code to calculate a CG matched the initial point mass or CG created in the FE model within a 0.01% difference. To validate the CG model even further, another test should be performed using a CG Platform prototype instrumented with load cells to generate new experimental data and compare them with the results from the FE model.
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Longmire, Leala S. "Design, Optimization, and Validation of a Rear Subframe to allow for the Integration of an Electric Powertrain." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1594907186413918.
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Rydman, Joakim. "Validation of blast simulation models via drop-tower tests." Thesis, Umeå universitet, Institutionen för fysik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-149403.
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This study aims to validate a screw joint simulation model used by BAE Systems in LS-DYNA during blast simulations. It is important that the screw joint simulation model is physically correct, since the simulation results can influence major design decisions. The study provides a short overview on the subject of bolts and screws, material deformation and stress and strain in materials, of the finite element method (FEM) and on some specific numerical methods used in this study. BAE Systems started a validation project of the screw joint simulation model in 2015, but it was not finished due to other priorities. In this older project some drop-tower tests measuring the axial force in a screw joint were conducted. These old tests can now serve as validation data for the screw joint simulation model. The screw joint simulation model used by BAE Systems is dependent on a special kind of finite element formulation; a so called beam element. This study provides a finite element analysis on this simulation model, which is implemented through an established industry FEM solver called LS-DYNA. The validation of the screw joint simulation model is done against three drop-tower experiments performed at 900, 1000 and 1100mm drop height respectively. The drop-tower experiments were replicated in LS-DYNA, with a prescribed velocity on the falling parts rather than simulating a free fall and non-elastic impact. A comparison between the simulation model using beam elements, that is used by BAE Systems, and a similar simulation model using solid elements is presented as part of the validation. To make sure that the result of the study is confident, a local mesh convergence study and a study of the mass scaling numerical method in LS-DYNA is also presented. The results show that the screw joint simulation model using beam elements is valid according to the available experimental data. In one of the experiments, where the drop-test was performed twice, an average maximum force on the screw was measured to be 33.5+-4.8 kN. Simulations of the same case, under the same conditions, using beam elements resulted in a maximum force on the screw of 35.4 kN, well within the experimental result range. In the other two drop-tower experiments, the simulated results showed correlation considering the error sources in the simulation model and the statistical spread that is present in the experimental results. The simulation model using beam elements is also similar to the results using solid elements, which also indicates that the beam model is valid. All in all, it is shown that the beam model can be used to produce safe results that either overestimate or place the simulations of the axial force in the screw in the upper spread of the measurements.
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Sylliaasen, Scott J. "The Development and Validation of a Finite Element Model of a Canine Rib For Use With a Bone Remodeling Algorithm." DigitalCommons@CalPoly, 2010. https://digitalcommons.calpoly.edu/theses/415.
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Studies are currently being performed to determine the effects of bisphosphonate treatments on the structure and density of bone tissue. One of the pathways for gaining a better understanding of the effects of this and other treatments involves creating a computer simulation. Theory suggests that bone tissue structure and density are directly related to the manner in which the tissue is loaded. Remodeling is the process in which bone tissue is resorbed in areas of low stress distributions, and generated in areas of high stress distributions. Previous studies have utilized numerical methods and finite element methods to predict bone structure as a result of stress distributions within the tissues. The Finite Element method was chosen for this study. This study was done on a canine (beagle) rib. The goal of this study was to develop an FEA model of the rib that would be used in conjunction with a bone remodeling algorithm, to model the behavior of the bone tissue. Appropriate boundary conditions, loads, and loading cycles were determined from literature, and applied. Respiration was assumed as the dominating activity; therefore the muscles involved in respiration were the primary source of the rib loading. The model also included an integrated UMAT sub-routine, which utilized data from the FEA model to iterate bone tissue densities and structures. The model closely predicted the porosities of the bone tissue, when compared to actual tissue samples, as well as what literature describes.
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Walters, David Michael. "Design, Validation, and Optimization of a Rear Sub-frame with Electric Powertrain Integration." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1437665533.
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Procházka, Vojtěch. "Výpočtová analýza oka ramene nápravy osobního automobilu." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2021. http://www.nusl.cz/ntk/nusl-443750.
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This thesis is focused on behavior of control arm opening with bushing pressed in. The tested component is a part of control arm of a car. The parts were tested in tensile and compressive strength. Real experiments were measured by optical system Aramis during the testing to determine deformations of the part. These tests are also modeled by a finite element method using an Abaqus software. In GOM Correlate software is created full-field comparison of deformation results from Aramis and FEA. Based on this comparison computational model is calibrated. Sensitivity analysis is performed at the end of the thesis.
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Maranhão, César Miguel Ramos. "FEM analysis in machining and experimental validation." Master's thesis, Universidade de Aveiro, 2008. http://hdl.handle.net/10773/2460.
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Mestrado em Engenharia MecânicaA presente investigação contempla a simulação numérica e validação experimental de processos de maquinagem. O estudo consiste na simulação numérica da maquinagem de materiais de alto desempenho como a liga de alumínio 7075 e o aço inox AISI 316 com validação experimental. Diversas simulações e validações foram conduzidas de modo a cobrir uma gama de parâmetros de maquinagem. Forças de corte e de avanço, potência de maquinagem, máxima temperatura de corte e deformação plástica foram validadas com sucesso. Finalmente, foram modeladas outras grandezas nomeadamente tensões residuais no aço inoxidável. ABSTRACT: The present investigation contemplates numerical simulation and experimental validation of machining processes. The study consists in simulating the machining of high performance materials like aluminium alloy 7075 and stainless steel AISI 316 with experimental validation. Several simulations and validations were conducted in order to cover a wide range of machining parameters. Cutting and feed forces, cutting power, maximum cutting temperature and plastic strain were validated with success. Finally, residual stresses in stainless steel were also modelled.
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Moravej, Maryam. "Développement et validation des matériaux métalliques pour stents cardiovasculaires biodégradables par dépôt électrolytique." Thesis, Université Laval, 2011. http://www.theses.ulaval.ca/2011/27897/27897.pdf.
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Les stents coronariens métalliques dégradables émergent comme une alternative possible aux stents permanents fabriqués à partir de métaux résistants à la corrosion comme l'acier inoxydable 316L. Le fer pur est un candidat intéressant pour les stents dégradables en termes de propriétés mécaniques, de dégradation et de biocompatibilité. Ce projet est le premier à étudier la faisabilité d’utiliser l'électroformage pour produire le fer comme matériau structural dans les stents dégradables. Dans ce projet, un processus de dépôt électrolytique a d’abord été développé. Les couches de fer produites ont une microstructure fine, une limite élastique élevée ainsi qu’une résistance à la traction ayant des valeurs comparables à celles de l'acier inoxydable 316L. Un traitement thermique de recuit à 550 ˚C pendant 1 h a produit une recristallisation dans le fer et a amélioré sa ductilité de 8 à 18 %. Des tests de corrosion par polarisation potentiodynamique et par immersion statique et dynamique ont permis l’étude de la dégradation du fer électroformé en solution de Hank. Il a été montré que le fer électrodéposé se corrode plus rapidement que le fer Armco ® déjà implanté comme stents biodégradables. L'effet de la densité de courant en tant que paramètre de l'électroformage sur la microstructure et la dégradation de fer a aussi été étudié. L’étude de diffraction d'électrons rétrodiffusés (EBSD) a montré que différentes microstructures, y compris la taille des grains et la texture, peuvent être produites à différentes densités de courant de 1 à 10 A dm-2. Le plus haut taux de dégradation a été obtenu pour le fer fabriqué à 5 A dm-2, car celui-ci possède la plus petite taille de grains et ceux-ci sont équiaxes avec des orientations aléatoires qui présentent un plus grand volume de joints de grains entraînant un taux de dégradation plus rapide. Enfin, le procédé d’électroformage a été appliqué avec succès pour la fabrication de mini-tubes de fer. Les mini-tubes de fer ont été électroformés sur les échantillons cylindriques d’étain qui ont été décollés par fusion du substrat après le processus. Les mini-tubes ont ensuite été utilisés pour la fabrication de stents de fer par découpe au laser. Les stents de fer ont montré une taille moyenne des grains de 5 µm après recuit et décapage à l'acide. Cette taille du grain est plus fine que celle généralement obtenue pour des stents SS 316L et pourrait fournir des propriétés mécaniques élevées et une dégradation ciblée pour les stents de fer électroformés.Degradable metallic coronary stents have emerged as possible alternatives for permanent stents fabricated from corrosion-resistant metals such as 316L stainless steel (316L SS). Pure iron has shown to be an interesting candidate for degradable stents in terms of mechanical properties, degradation and biocompatibility. This project is the first to investigate the feasibility of using electroforming process for production of iron for degradable stents where the material is used for a load-bearing application. In this project, firstly, an electroforming process was developed. The produced iron foils showed a fine microstructure and high yield and tensile strength were also obtained comparable to those of 316L SS. Annealing at 550˚C for 1h induced recrystallization in iron and improved its ductility from 8 to 18%. The investigation of the degradation of electroformed iron in Hank’s solution using potentiodynamic polarization, static immersion and dynamic degradation tests showed that it corrodes faster than Armco® iron previously investigated for degradable stents. The effect of current density as an electroforming parameter on the microstructure and thereby the degradation of iron was also studied. Electron backscatter diffraction (EBSD) showed that different microstructures including grain size and texture were produced at different current densities from 1-10 A dm-2. The highest degradation rate was obtained for iron fabricated at 5 A dm-2 since it possesses small grain size and equiaxed grains with random orientations providing more grain boundary volume can be held responsible for its faster degradation rate compared to the other iron samples. Finally, the electroforming process was successfully applied for the fabrication of iron tubes. Iron tubes were electroformed on Sn cylinders which were separated from them by melting after the process. The tubes were then used for the fabrication of iron stents by laser-cutting. Iron stents fabricated from electroformed tubes demonstrated an average grain size of 5 µm after annealing and acid-pickling. This grain size is finer than what usually obtained for 316L SS stents and could potentially provide high mechanical properties and targeted degradation for electroformed iron stents.
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Caycho-Rodríguez, Tomás, José M. Tomás, Miguel Barboza-Palomino, José Ventura-León, Miguel Gallegos, Mario Reyes-Bossio, and Lindsey W. Vilca. "Assessment of Fear of COVID-19 in Older Adults: Validation of the Fear of COVID-19 Scale." Springer, 2021. http://hdl.handle.net/10757/655711.
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There is no information in Peru on the prevalence of mental health problems associated with COVID-19 in older adults. In this sense, the aim of the study was to gather evidence on the factor structure, criterion-related validity, and reliability of the Spanish version of the Fear of COVID-19 Scale (FCV-19S) in this population. The participants were 400 older adults (mean age = 68.04, SD = 6.41), who were administered the Fear of COVID-19 Scale, Revised Mental Health Inventory-5, Patient Health Questionnaire-2 items, and Generalized Anxiety Disorder Scale 2 items. Structural equation models were estimated, specifically confirmatory factor analysis (CFA), bifactor CFA, and structural models with latent variables (SEM). Internal consistency was estimated with composite reliability indexes (CRI) and omega coefficients. A bifactor model with both a general factor underlying all items plus a specific factor underlying items 1, 2, 4, and 5 representing the emotional response to COVID better represents the factor structure of the scale. This structure had adequate fit and good reliability, and additionally fear of COVID had a large effect on mental health. In general, women had more fear than men, having more information on COVID was associated to more fear, while having family or friends affected by COVID did not related to fear of the virus. The Spanish version of the Fear of COVID-19 Scale presents evidence of validity and reliability to assess fear of COVID-19 in the Peruvian older adult population.
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Cabrera, Carlos Andres Cuenca. "Ductile failure prediction using phenomenological fracture model for steels: calibration, validation and application." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/3/3135/tde-27082018-075853/.
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The present thesis shows the analysis, calibration, and application of the stress modified criticai strain criterion to predict ductile failure for an A285 steel. To obtain the mechanical behavior of the material, experimental tests were carried out by implementation of 5 different types of geometries: smooth round bar, notched round bar (R=1 , 2, 3 mm), and, deep and shallow cracked SE(B) specimens. Then, for the calibration process of the mechanical properties finite element models were generated, using 30 solid elements with 8 nodes (C308), matching the geometry and the properties of the tested specimens. To calibrate the elastoplastic behavior was used the experimental and numerical response obtained from the smooth and notched round bar specimens; and, for the damage calibration was used the responses obtained from both deep and shallow crack SE(B) specimens. Once the mechanical properties were calibrated, then there were obtained the SMSC criterion factors represented by the equation ..... and, the damage condition which is represented by the displacement at failure (.......) and exponential factor (....). This calibrated model was able to recover the SE(B) experimental responses that validate the use of the characterized material in a complex structure. Then, the fully characterized material was applied in two pipelines which have externai initial circumferential elliptical crack; being the first one pipe with shallow crack and the second one with deep crack. Finally, both pipes were submitted to tension loads to predict the ductile damage behavior, obtaining the necessary load to the crack start growing, and the evolution of the failure.A presente dissertação apresenta o processo de análise, calibração e aplicação das propriedades mecânicas, incluindo o comportamento elastoplástico e de dano, para o aço A285, utilizando o critério \"Stress modified criticai strain\" (SMCS). Para obter o comportamento mecânico do material, testes experimentais foram realizados com a implementação de 5 tipos diferentes de geometrias: barra cilíndrica sem entalhe, barra cilíndrica com entalhe (R = 1, 2, 3 mm) e corpos de prova SE(B) com trinca inicial profunda e rasa. Para o processo de calibração das propriedades mecânicas foram gerados modelos de elementos finitos, utilizando elementos sólidos 30 com 8 nós (C3D8), que representam de forma adequada a geometria e as propriedades dos corpos de prova testados. Para calibrar o comportamento elastoplástico e iniciação do dano, utilizou-se a resposta experimental e numérica obtida para as amostras de barra cilíndrica com e sem entalhe; e, para a calibração da evolução do dano, foram utilizadas as respostas obtidas para os espécimes SEB de trincas profundas e rasa. Este modelo calibrado foi capaz de recuperar as respostas experimentais dos corpos de prova SE(B), o que valida o uso do material caracterizado em uma estrutura complexa. Uma vez calibradas as propriedades mecânicas, foram obtidos os fatores do critério SMSC representados pela equação ....... , e, a condição de dano que é representada pelo deslocamento na falha .... e o fator de amolecimento exponencial .... . Depois, o material totalmente caracterizado foi aplicado em dois dutos que possuem trinca elíptica circunferencial inicial externa; sendo o primeiro tubo com trinca superficial e o segundo com trinca profunda. Finalmente, ambos os tubos foram submetidos a cargas de tensão para prever o comportamento do dano dúctil, obtendo a carga necessária para o início do crescimento da trinca e a evolução da falha.
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Hoffstetter, Marc [Verfasser]. "Novel Designs for Middle Ear Implants : FEM based development and validation / Marc Hoffstetter." Aachen : Shaker, 2011. http://d-nb.info/1071529153/34.
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Vaglio-Gaudard, Claire. "Validation de données nucléaires du fer pour le calcul neutronique des réacteurs nucléaires." Grenoble INPG, 2010. http://www.theses.fr/2010INPG0028.
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Les données nucléaires du fer ont été complètement ré-évaluées dans la dernière bibliothèque européenne JEFF3. En dépit du fait que le fer soit largement utilisé dans l'industrie nucléaire, de larges incertitudes sont encore associées à ses données nucléaires, et en particulier à sa section inélastique qui est très importante pour le ralentissement des neutrons en physique des réacteurs. Un travail de validation des données nucléaires du 56Fe a été réalisé sur la bas de l'analyse d'expériences intégrales, principalement les expériences PERLE et Gaz des réacteurs expérimentaux de Cadarache. Le retour d1nterprétation de ces expériences a permis la mise en œuvre d'un processus de ré-estimation des données nucléaires du 56Fe. Les résultats ont mis en évidence que les données nucléaires du 56Fe dans la bibliothèque JEFF3. 1. 1 étaient connues avec précision. Il a alors été possible d'en déduire une nouvelle matrice de covariance a posteriori associée à JEFF3, avec des incertitudes réduitesIron nuclear data were completely re-evaluated in the latest JEFF3 European library. Despite the fact that iron is widely used in the nuclear industry, large uncertainties are still associated with its nuclear data, particularly its inelastic cross section which is very important in the neutron slowing down in reactor physics. A validation of 56Fe nuclear data was performed on the basis of the analysis of integral experiments, mainly the PERLE and gas experiments in experimental reactors in Cadarache. A process of re-estimating the 56Fe nuclear data was implemented on the basis of feedback from these two experiments. The results show that the 56Fe nuclear data in the JEFF3. 1. 1Iibrary are known with accuracy. A new a posteriori cova riance matrix and reduced uncertainties associated with JEFF3 can then be deduced
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Graham, Frank. "Development and validation of a bidirectionally coupled magnetoelastic FEM model for current driven magnetostrictive devices." College Park, Md.: University of Maryland, 2009. http://hdl.handle.net/1903/9354.
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Thesis (M.S.) -- University of Maryland, College Park, 2009.Thesis research directed by: Dept. of Aerospace Engineering. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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Portugal, André Fernandes Vaz. "Validation of a FEM-based tool and implementation of tyres' dry and wet braking prediction." Master's thesis, Universidade de Aveiro, 2016. http://hdl.handle.net/10773/22755.
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Mestrado em Engenharia MecânicaIn the present document, a new explicit FEM-based software developed to optimize tyre pattern geometry is presented. The new software calculates forces and displacements in tyre tread components after applying a load and a longitudinal shear displacement. To overcome long meshing and calculation times, simplifications are made. In this work, the usability of the simplifications is checked and the new software is adjusted and validated through the use of other FEM-based software in the market (Abaqus). To perform the validation, models are created, reproducing tyre tread blocks with different geometries, and the same simulation is reproduced in Abaqus. A set of simulations is run in both software. The results of the simulations are compared regarding the final shape, reaction forces and displacements in the nodes of the models. Finally, simple friction formulations are proposed and implemented in the new software, as well as a slip parameter and a water height level in the tyre footprint, in order to simulate braking performance in dry and wet surfaces. The results are then compared with experimental tests.
No presente documento, um novo software baseado no Método dos Elementos Finitos (MEF) explícito, desenvolvido para otimizar a geometria do padrão de pneus é apresentado. O novo software calcula forças e deslocamentos em componentes do piso dos pneus após a aplicação de uma carga e um deslocamento longitudinal. Para superar longos tempos de geração de malha e de cálculo, simplificações são feitas. Neste trabalho, a viabilidade para a utilização das simplificações é verificada e o novo software é ajustado e validado através da utilização de outro software baseado no MEF no mercado (Abaqus). Para executar a validação, modelos são criados, reproduzindo blocos do piso do pneu com diferentes geometrias, e a mesma simulação é reproduzida no Abaqus. Um conjunto de simulações é executado em ambos os softwares. Os resultados das simulações são comparados em relação à forma final, às forças de reação e deslocamentos nos nós dos modelos. Finalmente, simples formulações de fricção são propostas e implementadas no novo software, bem como um parametro de deslizamento e nível da altura da camada de água na pegada do pneu, a fim de simular o desempenho de travagem em piso seco e molhado. Os resultados são, então, comparados com testes experimentais.
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Sikora-Jasinska, Malgorzata. "Design, development and validation of iron-based composites for biodegradable implant applications." Doctoral thesis, Université Laval, 2018. http://hdl.handle.net/20.500.11794/31427.
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"Thèse en cotutelle : Doctorat en génie des matériaux et de la métallurgie, Université Laval, Québec, Canada, Philosophiæ doctor (Ph. D.) et Politecnico di Milano, Milano, Italie."Récemment, le Fe et ses alliages ont montré leur potentiel en tant que matériaux dégradables pour des applications biomédicales. Néanmoins, la vitesse de corrosion lente limite leurs performances dans certaines situations. Les matériaux composites à matrice de fer représentent une approche possible, non seulement pour améliorer leurs propriétés mécaniques, mais aussi pour accélérer et ajuster la vitesse de corrosion dans un environnement physiologique. Dans ce travail, des composites à base de Fe renforcés par des particules Mg2Si ont été proposés. Les poudres initiales ont été préparées par différentes combinaisons de procédés de mélange et de broyage, et finalement consolidées par laminage à chaud. L'influence de la microstructure sur les propriétés mécaniques et le comportement à la corrosion de Fe/Mg2Si a été étudiée. Les échantillons contenant des particules Mg2Si plus petites présentaient une distribution plus homogène du renforcement. Le rendement et l’état limite ultime à la traction ont augmenté par rapport à ceux du Fe pur. La présence des particules de renforcement a joué un rôle crucial dans la susceptibilité à l'attaque de corrosion localisée dans les composites à base de Fe. L'initiation de la corrosion et son développement ont été systématiquement suivis pour étudier le mécanisme de corrosion. L'importance des particules de Mg2Si dans le déclenchement des processus de corrosion a été expliquée. Des mesures électrochimiques et des tests d'immersion statique ont indiqué que l'ajout de Mg2Si pourrait augmenter le taux de corrosion du Fe. Il a été constaté que la taille et la distribution des particules de renfort jouaient un rôle crucial à l'uniformité de l'attaque de corrosion. Après, une série de tests d'immersion à différents intervalles d'exposition (20, 50 et 100 jours) à la solution modifiée de Hanks a été réalisée à fin d’évaluer le comportement de dégradation des composites Fe/Mg2Si et Fe pur préparés par différentes techniques de métallurgie des poudres. Les résultats ont révélé l’importance du Mg2Si dans la composition et la stabilité des films protecteurs formés lors des expériences de corrosion statique. Les composites Fe/Mg2Si présentaient des taux de dégradation plus élevés que le Fe pur à toutes les étapes du test d'immersion. Les taux de dégradation à des intervalles d'exposition distincts dépendaient fortement de la composition et de la stabilité des films protecteurs d'oxyde, d'hydroxyde, de carbonate et de phosphate formés sur les surfaces dégradées. La libération d'ions Fe dans la solution aux stades ultérieurs de l'expérience était limitée en raison de l'effet de barrière dû au dépôt insoluble. Cette étude fondamentale a servi de base aux processus de formation de film protecteur dans la solution de Hanks modifiée, permettant une identification détaillée de leurs caractéristiques.
Fe-based alloys have shown a potential as a degradable material for biomedical applications. Nevertheless, the slow corrosion rate limits their performance as a biodegradable implant. One approach to control and modify their corrosion properties is the reinforcement addition, to create metal matrix composites in which the second phase is aimed at tuning not only the mechanical properties but also the corrosion mode and rate in a physiological environment. This thesis presents an original and thorough contribution on a very pertinent topic, the design, development, and validation of a new Fe/Mg2Si composites prepared powder metallurgy. The initial powders were prepared by different combinations of mixing and high energy ball milling processes and finally consolidated by hot rolling. Mechanical properties, microstructural features, as well as the corrosion performance, were extensively investigated in relation to the reinforcement size and distribution. The composites made of small size reinforcement particles showed a general increase in tensile strength. For instance, high energy ball milled samples exhibited better tensile performances (YS = 523 MPa, UTS = 630 MPa) while having the lower ductility (around 4%). A fundamental understanding of corrosion initiation, protective film formation, and growth on Fe-based materials and leads to a design of smarter and surface responsive biomaterials with modulable degradation rates, at distinct stages of the corrosion process. Here, the corrosion performance of Fe/Mg2Si composites varied with the reinforcement size and distribution. The predominant localized pitting corrosion in Fe/Mg2Si prepared by mixing was replaced by a more uniform pattern found in samples produced by mechanical milling. Further, it was found that Mg2Si plays a significant role in the composition and stability of the protective films formed during the static corrosion experiments. Fe/Mg2Si showed a higher corrosion rate compared to that of pure Fe at all stages of the corrosion experiment (1, 10, 20, 50 and 100 days). Moreover, the final degradation products varied with the substrate chemical composition and microstructure. In case of pure Fe, low solubility (Fe3(PO4)2) covered the entire surface, while Fe/Mg2Si exhibited the presence of carbonates at the latest stages of the test. The details about the degradation behaviour during long-term exposure times to the physiological environment highlighted in this work add a new knowledge on corrosion mechanism of degradable implant materials. In particular, the ability to tune mechanical and corrosion behavior of the composites as a function of reinforcement properties and manufacturing method was experimentally verified, highlighting the microstructure-corrosion property relationship.
I biomateriali in ferro puro e in leghe a base di ferro presentano una combinazione interessante di proprietà meccaniche, elettrochimiche e biologiche; per questo motivo, questa classe di materiali metallici possono trovare utilizzo in applicazioni di tipo impiantistico biomedicale. Malgrado ciò, nonostante le sue soddisfacenti proprietà meccaniche, questo elemento impiegato allo stato puro mostra un inconveniente rilevante - un basso tasso di degradazione. L’oggetto di questa tesi è lo studio di un nuovo gruppo di materiali biodegradabili compositi a matrice ferrosa (Fe/Mg2Si), in cui il Fe costituisce la matrice e il Mg2Si è impiegato come rinforzo; questi materiali sono stati sviluppati con tecniche di metallurgia delle polveri, e presentano un, alta resistenza meccanica come caratteristica principale. Le polveri che costituiscono i materiali di partenza sono stati preparati con diverse combinazioni di procedure oltre al semplice mescolamento e/o high energy ball milling (macinatura in mulino a sfere a alta energia). Tutte le formulazioni preparate sono state compattate attraverso laminazione a caldo. Le proprietà meccaniche, le caratteristiche microstrutturali, la composizione delle fasi e le prestazioni in termini di corrosione sono state studiate dettagliatamente, in relazione alla dimensione delle particelle di rinforzo e della loro distribuzione. Lavori precedenti hanno confermato l’efficacia dell’aggiunta di una seconda fase, soprattutto se finemente dispersa, per aumentare il tasso di degradazione di materiali metallici per applicazioni biomedicali a base Fe: gli esperimenti condotti in questo lavoro hanno confermato che i compositi Fe/Mg2Si hanno mostrato, rispetto al Fe puro che compone la matrice, non solo una resistenza meccanica più elevata, ma anche un tasso di degradazione più alto negli esperimenti di laboratorio in vitro. Infine, i materiali ottenuti tramite high energy ball milling, presentano una resistenza alla trazione migliore (carico di snervamento= 523 MPa, resistenza alla trazione = 630 MPa), ma contemporaneamente una ridotta duttilità (circa 4%). Una attenzione particolare è stata posta nello studio degli effetti della presenza di Mg2Si sui meccanismi di corrosione.Tutti i compositi studiati hanno mostrato un tasso di degradazione più elevato rispetto alla matrice fabbricata con la stessa procedura; inoltre, la formazione del film di prodotti di degradazione sulla superficie del materiale cambiava in maniera rilevante in funzione della composizione chimica del substrato e della sua microstruttura. Nel caso del Fe puro, cristalli isolati di vivianite (Fe3(PO4)2) erano presenti su tutta la superficie, mentre carbonati di Fe si formavano principalmente sulla superficie dei compositi, specialmente negli ultimi stadi del processo di degradazione.
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Raffai, Peter. "Vytvoření a validace výpočtového FEM modelu kliky dveří pro crashové výpočty." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2012. http://www.nusl.cz/ntk/nusl-230249.
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The aim of this master’s thesis was to create a component model of a door handle stiffener used by the Volkswagen concern, which can be used for crash computations. Also to tune its parameters the way, its behavior corresponds the most to the real part’s. In the theoretical part the current regulations of the Euro NCAP are presented, concerning the testing and evaluation of the passive safety of new vehicles. Attention is focused on the evaluation of the side impact barrier tests, where the effect of the door handle stiffener’s damage is reflected the most. Shown are the reasons for the effort to simulate the real behavior of the stiffener, the factors, which initialized the born of the studied problem. The practical part starts with the creation of the FEM mesh of the part based on its 3D CAD model, also describes the requirements for the mesh quality, as well as the used tools and methods. Further on investigated are the characters of real damages of the door handle area during side impacts, based on which the component tests are proposed for the validation of the simulation model. Experimental research consists of the stiffener’s testing for simple bend and twist loads, three specimens each. After the execution of the tests the results get compared with the corresponding simulations. Modifications are made on the model according to the acquired results: refinement of the FEM mesh, new material model usage with failure for shell elements and definition of real material characteristics for the used thermoplastics. The latest obtained simulation dependencies are compared with the measured values again, the results are evaluated at last.
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Wingo, Brooks C. "Development and validation of a scale to measure fear of physical response to exercise among overweight and obese adults." Thesis, Birmingham, Ala. : University of Alabama at Birmingham, 2010. https://www.mhsl.uab.edu/dt/2010p/wingo.pdf.
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Tomazin, kelly Jaqueline da Costa Galinari. "Adaptação transcultural e validação da escala childbirth fear prior to pregnancy (CFPP) para utilização no brasil." Botucatu, 2019. http://hdl.handle.net/11449/181891.
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Orientador: Milena Temer JamasResumo: Introdução: O enfermeiro tem reconhecimento mundial na mudança do modelo de assistência ao parto, resgatando o nascimento como um processo natural, no qual os sentimentos e preocupações da parturiente devem ser respeitados. Nesta perspectiva surge a preocupação com a formação acadêmica dos futuros enfermeiros. Entende-se que a forma como o profissional percebe o processo de nascimento pode influenciar a assistência. O medo e a interpretação desse período como sofrimento e dor podem estimular intervenções desnecessárias no intuito de abreviar vivências consideradas negativas. Considerando a inexistência de instrumento voltado para a população brasileira, capaz de avaliar o medo do parto antes da gestação, o objetivo do presente estudo foi realizar a adaptação transcultural e analisar as evidências de validade e confiabilidade da versão brasileira da Escala Childbirth Fear Prior to Pregnancy (CFPP). Método: Trata-se de estudo do tipo metodológico, aprovado pelo Comitê de Ética em Pesquisa da Faculdade de Medicina de Botucatu, parecer nº 2.428.902, com amostra de conveniência composta por 146 alunos de graduação de enfermagem. A adaptação transcultural da Versão Brasileira da escala seguiu as etapas amplamente utilizadas na literatura: Avaliação por comitê de especialistas e Pré-teste com avaliação da população alvo. Participaram do estudo 146 graduandos de enfermagem da Faculdade de Medicina de Botucatu – FMB e do Centro Universitário Católico Salesiano Auxilium – UniSALESIANO.... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Introduction: The nurse has a world acknowledgement on changing birth assistance, recovering birth as a natural process as well as feelings and concerns from parturient being respected. Thus, an interest has been raised on nursing academic graduation. In addition, the meaning as a professional caring about the birthing process can influence the service. Fear, and the interpretation of this period as suffer and pain might stimulate unnecessary interventions as an intention of shorten considerable negative experiences. Furthermore, considering nonexistent tool related to Brazilian population, capable of measuring fear before pregnancy, the main objective of this paper was to make a transcultural adaptation and to analyze the evidences of efficacy and reliability for the brazilian version of the Childbirth Fear Prior to Pregnancy (CFPP). Methodology: This study has a methodological manner, approved by the Ethics in Research committee of Medical Science College of Botucatu, under number 2.428.902, with a convenience sample made of 146 nursing graduating students. The Brazilian version for the transcultural adaptation has followed the steps mentioned in the literature. Evaluation by a specialist committee and pre-test with assessment of the target audience. Nevertheless, 146 of nursing graduation students from Medical Science College of Botucatu – FMB and from the Salesians Catholic University Center - UniSALESIANO took part in this study. Data was collected from February to Augus... (Complete abstract click electronic access below)
Mestre
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Ramalingam, Srinivasan. "SIMULATION AND EXPERIMENTAL VALIDATION OF AIRBORNE AND STRUCTURE-BORNE NOISE TRANSMISSION IN HVAC PLENUMS." UKnowledge, 2012. http://uknowledge.uky.edu/me_etds/6.
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This research demonstrates the usage of numerical acoustics to model sound and vibrational energy propagation in HVAC ducts and plenums. Noise and vibration in HVAC systems propagates along three primary paths that can be classified as airborne direct, airborne indirect and structure-borne. The airborne direct path was simulated using acoustic FEM with special boundary conditions to handle the diffuse acoustic field loading and the baffled termination. The insertion loss for a number of different plenum geometries was compared to published measurement results. Results were in good agreement both below and above the cutoff frequency. Additionally, the airborne indirect path, often termed breakout noise by the HVAC community, was assessed using Statistical Energy Analysis (SEA). This path was examined experimentally by placing a loudspeaker inside the air handler and measuring the sound power transmitted through the walls. SEA results compared favorably with the measured results in one-third octave bands even at low frequencies. Finally, the structure-borne path was considered by exciting the walls of the aforementioned air handler using an electromagnetic shaker. The panel vibration and the sound power radiated from the panels were measured. Results were compared with the SEA with good agreement provided that SEA loss factors were determined experimentally.
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Witherspoon, Luke. "In Silico Mining of a System Wide Transcriptional Profiling Database for Clinically Relevant Gene Modulation by FDA Approved or FDA Ready Agents; Validation of a Novel Translational Approach." Thèse, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/20118.
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It has been recognized that small molecules can affect a substantial proportion of the human transcriptome in ways that are currently unknown and difficult to predict. Working with the Broad Institute, using their Connectivity Map database, we have worked to identify compounds anticipated to modulate two diseases; myotonic dystrophy (DM1) and Duchenne muscular dystrophy (DMD). DM1 stems from an expanded CTG repeat found in the DMPK gene. The down regulation of DMPK mRNA represents a valid therapeutic avenue. DMD is characterized by degeneration of muscle, caused by mutations in the dystrophin gene. One therapeutic strategy for DMD is to increase the dystrophin homologue utrophin. We have identified a number of compounds capable of decreasing DMPK mRNA and others which increase utrophin mRNA and protein. We hope our success in compound identification not only leads to potential therapeutics for these diseases, but highlights the usefulness of using in silico screens.
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Bourgana, Mohamed Taoufik. "Modélisation et validation expérimentale d'un modèle vibroacoustique d'un silencieux d'une motoneige." Mémoire, Université de Sherbrooke, 2017. http://hdl.handle.net/11143/9862.
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Ce mémoire traite la modélisation et la validation expérimentale du bruit d’un silencieux de motoneige. La première phase du projet consiste à modéliser numériquement le système d’échappement avec les méthodes numériques suivantes : éléments finis et éléments finis de frontière, afin d’évaluer ses performances acoustiques : perte par transmission, bruit de bouche et bruit de paroi. Une deuxième phase du projet consiste à valider expérimentalement les performances acoustiques calculées numériquement. La dernière phase du projet se consacrera à une étude paramétrique expérimentale d’un silencieux sur banc moteur. En conclusion, les résultats des modèles numériques mis en œuvre concordent bien avec les résultats expérimentaux. Cependant, les aspects non linéaires rencontrés à la dernière phase du projet n’ont pas été étudiés davantage.
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Sverrisdóttir, Kristín. "Improvements and Validation of THUMS Upper Extremity : Refinements of the Elbow Joint for Improved Biofidelity." Thesis, KTH, Skolan för kemi, bioteknologi och hälsa (CBH), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-261099.
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Introduction One out of five reported motor vehicle collision injuries occur to the upper extremities. Certain parts of The Total HUman Model for Safety (THUMS) lack validation against experimental data, including the elbow. The aim of this project is to refine and validate the elbow joint of THUMS, with focus on anatomical response of the elbow during axial impact applied to the wrist. Methods Internal contacts in the elbow were modified and new contacts assigned between bones and ligaments of the elbow. The posterior part of the radial- and ulnar collateral ligaments, and joint capsule was implemented to the model. Elasticmodulus of the cortical bones of the elbow was increased as well as the shell thickness of the humeral cortical bone. The updated model was validated against an experiment where an axial load was applied to the wrist of a female cadaver. The experimental resultant force in the wrist was then compared with the wrist force obtained from the simulations. Results The correlation between the experimental and simulation resultant wrist force for the updated model resulted in a CORA score of 0.882. This gave a 6.7% higher CORA score compared with the original model. Hourglass energy was reduced from 63.52% of internal energy to 0.78%. Energy ratio and contact energies indicated that the simulation was stable. Discussion Movement of elbow bones was assessed to be more anatomically correct, by accounting for the posterior ligament and elbow capsule support. The contact peak force in the humerus was lower and occurred earlier in the simulation in the updated model compared to the original. This is believed to be due to the reduced gap between the elbow bones after increasing the shell thickness of the humeral cortical bone. The model setup resembled the experiment in a good manner. Conclusion The upper extremity of THUMS was refined for improved biofidelity, with focus on the anatomical response of the elbow joint under an axial impact. However, further model improvements are suggested as well as extended validated against other experimental impact results.Introduktion En av fem rapporterade krockskador med motorfordon förekommer i de övre extremiteterna. Vissa strukturer hos Total HUman Model for Safety (THUMS) saknar validering gentemot experimentell data, där armbågen är ett av dem. Syftet med detta projekt är att förfina och validera armbågsleden hos THUMS, med fokus på dess anatomiska respons under axiellt islag applicerad på handleden. Metod Interna kontakter i armbågen modifierades och nya kontakter tilldelades mellan ben och ligament. De posteriora delarna av kollateral ligament hos radius och ulna implementerades i modellen, så även armbågens ledkapseln. Elasticitetsmodulen hos de kortikala benen i armbågen höjdes och skalets tjocklek idet humerala kortikala benet utökades. Den uppdaterade modellen validerades mot ett experiment där en axiell belastning hade applicerats mot en kvinnlig kadavers handled. Den resulterande kraften i handleden från experimentet jämfördes sedan med erhållen kraft i handleden från simuleringarna. Resultat Korrelationen mellan den experimentella kraften och simulerade kraften hos den uppdaterade modellen resulterade i ett CORA-poäng på 0,882. Detta är en ökning med 6,7% jämfört med den ursprungliga modellen. Hourglassenergin reducerades från 63,52% av inre energi till 0,78%. Energiförhållandet och kontaktenergier indikerade stabil simulering. Diskussion Rörelsen av armbågens ben bedömdes vara mer anatomiskt korrekt, med hänsyn till stödet från de posteriora ligamentet och armbågens ledkapsel. Den maximala islagskraften i humerus minskade och uppträdde tidigare i simuleringen hos den uppdaterade modellen jämfört med originalet. Detta tros bero på reducerat avstånd mellan armbågens ben genom ökandet av skaltjockleken hos det humeralakortikala benet. Modelluppställningen motsvarade experimentets uppställning. Konklusion De övre extremiteterna av THUMS förfinades i syfte att förbättra biofideliteten. Fokus låg på armbågens anatomiska respons under ett axielltislag. Både ytterligare förbättringar av modellen och utökad validering mot andra experimentella islag rekommenderas.
Technology
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Mayorca, María Angélica. "Development and Validation of a Numerical Tool for theAeromechanical Design of Turbomachinery." Licentiate thesis, KTH, Energy Technology, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-11992.
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In aeromechanical design one of the major rules is to operate under High Cyclic Fatigue (HCF) margins and away from flutter. The level of dynamic excitations and risk of HCF can be estimated by performing forced response analyses from blade row interaction forces or Low Engine Order (LEO) excitation mechanisms. On the other hand, flutter stability prediction can be assessed by calculation of aerodynamic damping forces due to blade motion. In order to include these analyses as regular practices in an industrial aeromechanical design process, interaction between the fields of fluid and structural dynamics must be established in a rather simple yet accurate manner. Effects such as aerodynamic and structural mistuning should also be taken into account where parametric and probabilistic studies take an important role.
The present work presents the development and validation of a numerical tool for aeromechanical design. The tool aims to integrate in a standard and simple manner regular aeromechanical analysis such as forced response analysis and aerodynamic damping analysis of bladed disks.
Mistuning influence on forced response and aerodynamic damping is assessed by implementing existing model order reduction techniques in order to decrease the computational effort and assess results in an industrially applicable time frame. The synthesis program solves the interaction of structure and fluid from existing Finite Element Modeling (FEM) and Computational Fluid Dynamics (CFD) solvers inputs by including a mapping program which establishes the fluid and structure mesh compatibility. Blade row interaction harmonic forces and/or blade motion aerodynamic damping forces are inputs from unsteady fluid dynamic solvers whereas the geometry, mass and stiffness matrices of a blade alone or bladed disk sector are inputs from finite element solvers. Structural and aerodynamic damping is also considered.
Structural mistuning is assessed by importing different sectors and any combinations of the full disk model can be achieved by using Reduced Order Model (ROM) techniques. Aerodynamic mistuning data can also be imported and its effects on the forced response and stability assessed. The tool is developed in such a way to allow iterative analysis in a simple manner, being possible to realize aerodynamically and structurally coupled analyses of industrial bladed disks. A new method for performing aerodynamic coupled forced response and stability analyses considering the interaction of different mode families has also been implemented. The method is based on the determination of the aerodynamic matrices by means of least square approximations and is here referred as the Multimode Least Square (MLS) method.
The present work includes the program description and its applicability is assessed on a high pressure ratio transonic compressor blade and on a simple blisk.
Turbopower
AROMA
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Quenneville, Isabelle. "Adaptation québécoise-française et validation de l'index of dental anxiety and fear (échelle de peur et d'anxiété des traitements dentaires)." Thesis, Université Laval, 2013. http://www.theses.ulaval.ca/2013/30187/30187.pdf.
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Il existe actuellement peu de tests validés de façon convaincante de langue québécoise-française pour mesurer l’anxiété liée aux soins dentaires chez l’adulte. On retrouve par ailleurs un tel test validé en langue anglaise, l’IDAF-4C+ (Annexe IV), dont les détails ont été publiés en 2010 [1]. L’objectif de la présente étude était de traduire l’IDAF-4C+ en langue québécoise-française utilisée au Canada, de l’adapter et de le valider. Un groupe d’experts a été consulté afin de discuter de la traduction. La clarté des questions a été vérifiée auprès de patients. La consistance interne et la stabilité temporelle ont été établies par analyse statistique. Finalement, on a démontré la validité du test à l’aide d’une corrélation positive entre l’Échelle de Peur et d’Anxiété des Traitements Dentaires (EPATD) et des tests d’anxiété générale et situationnelle bien établis dans le domaine de la psychologie (Annexes VII). La validité transculturelle des tests utilisés a été démontrée. Des tests physiologiques ont également été utilisés pour valider les résultats.
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Mayorca, María Angélica. "Development and Validation of a Numerical Tool for the Aeromechanical Design of Turbomachinery." Licentiate thesis, KTH, Kraft- och värmeteknologi, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-11992.
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In aeromechanical design one of the major rules is to operate under High Cyclic Fatigue (HCF) margins and away from flutter. The level of dynamic excitations and risk of HCF can be estimated by performing forced response analyses from blade row interaction forces or Low Engine Order (LEO) excitation mechanisms. On the other hand, flutter stability prediction can be assessed by calculation of aerodynamic damping forces due to blade motion. In order to include these analyses as regular practices in an industrial aeromechanical design process, interaction between the fields of fluid and structural dynamics must be established in a rather simple yet accurate manner. Effects such as aerodynamic and structural mistuning should also be taken into account where parametric and probabilistic studies take an important role. The present work presents the development and validation of a numerical tool for aeromechanical design. The tool aims to integrate in a standard and simple manner regular aeromechanical analysis such as forced response analysis and aerodynamic damping analysis of bladed disks. Mistuning influence on forced response and aerodynamic damping is assessed by implementing existing model order reduction techniques in order to decrease the computational effort and assess results in an industrially applicable time frame. The synthesis program solves the interaction of structure and fluid from existing Finite Element Modeling (FEM) and Computational Fluid Dynamics (CFD) solvers inputs by including a mapping program which establishes the fluid and structure mesh compatibility. Blade row interaction harmonic forces and/or blade motion aerodynamic damping forces are inputs from unsteady fluid dynamic solvers whereas the geometry, mass and stiffness matrices of a blade alone or bladed disk sector are inputs from finite element solvers. Structural and aerodynamic damping is also considered. Structural mistuning is assessed by importing different sectors and any combinations of the full disk model can be achieved by using Reduced Order Model (ROM) techniques. Aerodynamic mistuning data can also be imported and its effects on the forced response and stability assessed. The tool is developed in such a way to allow iterative analysis in a simple manner, being possible to realize aerodynamically and structurally coupled analyses of industrial bladed disks. A new method for performing aerodynamic coupled forced response and stability analyses considering the interaction of different mode families has also been implemented. The method is based on the determination of the aerodynamic matrices by means of least square approximations and is here referred as the Multimode Least Square (MLS) method. The present work includes the program description and its applicability is assessed on a high pressure ratio transonic compressor blade and on a simple blisk.QC 20110324
Turbopower
AROMA
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Steinmetz, Sarah. "Design, Implementation, and Validation of an Experimental Setup for Closed-Loop Functional Electrical Stimulation Applications." Honors in the Major Thesis, University of Central Florida, 2007. http://digital.library.ucf.edu/cdm/ref/collection/ETH/id/1192.
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This item is only available in print in the UCF Libraries. If this is your Honors Thesis, you can help us make it available online for use by researchers around the world by following the instructions on the distribution consent form at http://library.ucf.edu/Systems/DigitalInitiatives/DigitalCollections/InternetDistributionConsentAgreementForm.pdf You may also contact the project coordinator, Kerri Bottorff, at kerri.bottorff@ucf.edu for more information.Bachelors
Engineering and Computer Science
Mechanical Engineering
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Mbemba, François. "Mise au point et validation d'une méthodologie d'enquêtes : Alimentaires à l'usage du Congo." Nancy 1, 1986. http://www.theses.fr/1986NAN10080.
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L'étude de la consommation alimentaire et des facteurs qui la conditionnent fournit des données fondamentales pour comprendre comment s'effectue la couverture des besoins des groupes d'individus. Les enquêtes alimentaires permettent la connaissance qualitative et quantitative de la consommation soit d'une population importante ou d'un groupe restreint, soit d'un individu. Cette thèse présente l'étude d'une méthodologie d'enquêtes alimentaires qui sera appliquée au Congo. Élaboration d'une table de composition des aliments, du Congo, par compilation des tables à partir de celles de la Fao à l'usage de l'Afrique de Renaud et de Souci. Enquête de consommation alimentaire sur des congolais en séjour d'études en France, Enquêtes exploitées par la technique que nous avons mise au point
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Suzanne, Mathieu. "Conditions d'utilisation de modèles numériques pour l'évaluation de scénarios de départ de feu dans un cadre d'investigation post-incendie." Phd thesis, INSA de Rouen, 2009. http://tel.archives-ouvertes.fr/tel-00557898.
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Devant le besoin de nouveaux outils d'aide à l'investigation post-incendie, cette thèse se propose d'évaluer le recours à des modèles numériques pour apprécier un scénario proposé par un expert. Pour cela, les conditions d'utilisation de la version 4 de Fire Dynamics Simulator (FDS) ont été déterminées dans une optique de reconstitution de sinistres. Une méthode a ensuite été développée afin de confronter les résultats des simulations aux observations faites lors de l'investigation : cette méthode se base sur l'utilisation de multiples points de comparaison qui sont des effets thermiques ou mécaniques remarquables sur un matériau. Les résultats obtenus ont ensuite été utilisés pour la simulation de deux cas réels. Le premier s'attache à comparer, à des simulations, des mesures de propagation de flammes à la surface d'un matelas dans deux configurations différentes. Cela est réalisé afin d'évaluer le modèle de combustion solide de FDS dans différentes conditions de ventilation. La seconde application est la reconstitution d'un incendie ayant fait une victime dans un appartement. Ce second cas a été choisi dans le but d'évaluer les méthodes de simulation et d'utilisation des points de comparaison établies dans les premiers chapitres.
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Naab-Levy, Adam O. "Enhanced Distance Measuring Equipment Data Broadcast Design, Analysis, Implementation, and Flight-Test Validation." Ohio University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1449158180.
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Oyarzun, Laura Cristina Verfasser], Georgios [Akademischer Betreuer] Sakas, Dieter W. [Akademischer Betreuer] [Fellner, and Reto [Akademischer Betreuer] Bale. "Graph-matching and FEM-based Registration of Computed Tomographies for Outcome Validation of Liver Interventions / Cristina Oyarzun Laura. Betreuer: Georgios Sakas ; Dieter W. Fellner ; Reto Bale." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2016. http://d-nb.info/111204499X/34.
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Sakji, Mohamed Seddik. "Modélisation probabiliste et validation expérimentale du transfert thermique et du comportement thermomécanique avec endommagement d'une plaque multicouche carton-plâtre-carton soumise au feu." Marne-la-Vallée, 2006. http://www.theses.fr/2006MARN0286.
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Ditzel, Kropiwiec Cássio. "Framework for distributed firewall administration in a multi-constraint security policies context." Paris 6, 2009. http://www.theses.fr/2009PA066162.
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Ce travail présente une nouvelle approche pour représenter ces règles de sécurité d’un réseau global. Le framework proposé définit un langage de règles de haut niveau, qui permet les spécifications de ces règles selon des modèles de sécurité obligatoires, discrétionnaires et de propriétés. Ce Framework est capable de gérer simultanément les trois dimensions et décrit de manière cohérente les autorisations résultantes sous la forme d’une représentation abstraite, indépendante de la façon dont elles seront mises en place, et sans violer l’objectif de sécurité globale. Le Framework inclue aussi un mécanisme responsable pour la traduction de la représentation abstraite des autorisations en scripts/règles de configuration de bas-niveau pour des pare-feu de différents modèles et fabricants, permettant son utilisation pour la configuration de réseaux hétérogènes. Chaque dimension peut être définie par des personnes ayant différents rôles, permettant une coopération pour la définition d’une politique globale. Le Framework est formalisé avec Z afin de démontrer sa complétude et sa rigueur. Une étude d’extensibilité est présentée pour expliquer le comportement du Framework pour des réseaux plus larges.
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Briones, Maria. "Validating the Accuracy of Neatwork, a Rural Gravity Fed Water Distribution System Design Program, Using Field Data in the Comarca Ngöbe-Bugle, Panama." Scholar Commons, 2018. https://scholarcommons.usf.edu/etd/7268.
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Despite the sustainable development goals to increase access to improved water there are still 884 million people in the world without access to an improved water source (WHO, 2017). One method to improve access to water in rural, mountainous areas, is through construction of gravity fed water distribution systems. These systems should be designed based upon fundamental principles of hydraulics. One method of doing so in a time efficient manner with minimal engineering knowledge is to utilize a downloadable computer program such as Neatwork, which aids in design of rural, gravity fed water distribution systems and has been used by volunteers in Peace Corps Panama for years. It was the goal of this research to validate the results of the Neatwork program by comparing the flow results produced in the simulation program with flow results measured at tap stands of a rural gravity fed water distribution system in the community of Alto Nube, Comarca Ngöbe Bugle, Panama.
The author measured flow under default Neatwork conditions of 40% faucets open in the system (in the field an equivalent of 8 taps) to have an initial basis as to whether the Neatwork program and field conditions yielded corresponding flows. The second objective would be to vary the number of taps open if the default condition did not produce comparable results between the field and the simulation, to pinpoint if under a certain condition of open faucets in the system the two methods would agree. The author did this by measuring flow at varying combinations from 10-100% of the open taps in the system (2-20 taps). Lastly the author observed the flow differences in the Neatwork program against the field flows, when the elevation of water in the water reservoir is set to the Neatwork default, where elevation of water is the tank outlet (at the bottom of the tank) versus when the elevation is established at the overflow at the tank (at the top of the tank) for the case of two taps open.
The author used paired t-tests to test for statistical difference between Neatwork and field produced flows. She found that for the default condition of 40% taps open and all other combinations executed between 30-80% taps open, the field and Neatwork flows did not produce statistically similar results and, in fact, had the tendency to overestimate flows. The author also found that the change in water elevation in the storage tank from outlet to overflow increased the flow at the two taps measured by 0.140 l/s and 0.145 l/s and in this case, did not change whether the flows at these taps were within desired range (0.1 -0.3 l/s). Changing the elevation of the water level in the tank in the Neatwork program to correspond to a “full” tank condition is not recommended, as assuming an empty tank will account for seasonal changes or other imperfections in topographical surveying that could reduce available head at each tap. The author also found that the orifice coefficients, θ, of 0.62 and 0.68, did not demonstrate more or less accurate results that coincided with field measurements, but rather showed the tendency of particular faucets to prefer one coefficient over the other, regardless of combination of other taps open in the system.
This study demonstrates a consistent overestimation in flow using the computer program Neatwork. Further analysis on comparisons made show that between field and flow results across each individual faucet, variations between Neatwork and the field were a result of variables dependent upon the tap, such as flow reducers or errors in surveying. Flow reducers are installed before taps to distribute flow equally amongst homes over varying distances and elevations and are fabricated using different diameter orifices depending on the location of the tap. While Neatwork allows the user to simulate the effect of these flow reducers on tap flow, it may not account for the imperfect orifices made by the simple methods used in the field to make such flow reducers.
The author recommends further investigation to be done on the results of field flow versus Neatwork simulated flow using other methods of flow reducer fabrication which produce varying degrees of accuracy in orifice sizing. The author also recommends executing these field measurements over a greater sample size of faucets and more randomized combination of open/closed taps to verify the results of this research. More work should be done to come up with a practical solution for poor and rural communities to fabricate and/or obtain more precisely sized flow reducers. A full sensitivity analysis of the input variables into the Neatwork program should be performed to understand the sensitivity of varying each input.
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Lhuillier-Marchand, Alexis. "Propagation des feux de végétation : expérimentations à l’échelle du laboratoire et validation d’un propagateur." Thesis, Université de Lorraine, 2016. http://www.theses.fr/2016LORR0131/document.
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Ce travail est consacré à l’étude expérimentale et numérique de la propagation des feux de végétation à l’échelle du laboratoire. Une méthode de suivi de front de flamme par caméras visibles a été développée pour reconstruire et mesurer les propriétés du front au cours du temps. Les données recueillies comprennent la vitesse de propagation (Rate Of Spread), l’épaisseur du front, les longueurs du contour du front, les profils de hauteur et la puissance du feu. Une campagne expérimentale de 105 expériences de propagation sur de la frisure de bois a été réalisée sur la plateforme PROMETHEI (Plateforme de Recherche Opérationnelle en Métrologie Thermique dédiée aux Essais Incendies) du laboratoire LEMTA. Elle contient notamment une étude de l’effet de la largeur et de la charge sur la dynamique de propagation (sur la vitesse et l’épaisseur). Une base de données (en libre accès sur internet) dédiée aux feux de végétation a été créée et fournit les positions du front de flamme (avant et arrière) pour 85 expériences. Un modèle de propagation Petit Monde à réseau de cellules hexagonales a été également développé en parallèle. Plusieurs approches sont proposées pour déterminer l’évolution de l’état des cellules : la première modélise le transfert radiatif alors que la deuxième se base sur une fonction de distribution identifiée. Un algorithme d’optimisation par essaims particulaires (PSO) est employé pour estimer les différents paramètres du modèle à l’aide des résultats expérimentaux. Le modèle Petit Monde est ensuite comparé à des expériences de propagation comprenant des coupures de combustible ou des rétrécissements/élargissements de la largeur du litThis work is devoted to the experimental and numerical study of wildland fire spread at laboratory scale. A tracking fire front method using visible cameras was used in order to follow the fire front positions during the propagation and to evaluate some fire front properties. The data include the Rate Of Spread (ROS), the fire front width, the length of fire, the profile of flames and the Heat Release Rate. An experimental campaign of 105 fire spread tests with wood shaving as fuel was conducted on the PROMETHEI plateform (Plateforme de Recherche Opérationnelle en Métrologie Thermique dédiée aux Essais Incendies) of the laboratory LEMTA. This campaign was essentially focused on the effect of the fuel bed width and the fuel loading on the fire dynamics (particularly on the ROS and fire width). An open-source data base provides the positions of the front and backing fire as a function of time. A fire spread model based on the small world concept with a hexagonal cell network was developed. Two approaches were studied: the first one is based on a radiative transfer model for the definition of the cell states and the other one is based on an estimated distribution function. A particle swarm optimization (PSO) algorithm was used for the identification of the different parameters of the model using the experimental results. Then, the model was compared to other experiments included fuel breaks or narrowing/widening of the fuel bed width
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Figueiredo, Ester Ribeiro de. "Avaliação da aplicação e normas vigentes de validação de bioensaios para pesquisa clínica." reponame:Repositório Institucional da FIOCRUZ, 2014. https://www.arca.fiocruz.br/handle/icict/13169.
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Previous issue date: 2014Fundação Oswaldo Cruz. Instituto de Tecnologia em Fármacos/Farmanguinhos. Rio de Janeiro, RJ, Brasil.
As vacinas são produtos imunobiológicos reconhecidamente seguros, eficazes e com grande participação no controle e/ou erradicação de doenças imunopreveníveis, comprovando uma grande relação custo-benefício. Atualmente, Bio-Manguinhos é o principal fornecedor de vacinas para o Ministério da Saúde e para suprir as demandas do Programa Nacional de Imunização utiliza como uma das estratégias de fornecimento, acordos de transferência de tecnologia com empresas mundiais, como a GlaxoSmithKline e a Sanofi Pasteur, com o objetivo de suprir demandas epidemiológicas brasileiras e adquirir desenvolvimento tecnológico para a instituição, o que caracteriza um processo inovador de grande relevância. Os produtos gerados através deste processo precisam ser submetidos a testes de Controle de Qualidade e pesquisa clínica para comprovar a qualidade e a confirmação terapêutica, através de metodologias analíticas e bioanalíticas (bioensaios) validadas. Este trabalho tem como objetivo avaliar a aplicabilidade da RDC 27 da ANVISA e analisar os demais documentos de validação de bioensaios preconizados pela OMS, FDA, USP e EMEA. Para isto, foi realizada uma análise desses documentos para a verificação de diferenças, semelhanças e aplicação. Um estudo de caso foi realizado através da validação do teste de neutralização por redução de placa de lise para sarampo em placas de 96 poços (MICRO-PRNT) que é considerado pela literatura o método mais sensível e específico para a qualificação e quantificação de anticorpos neutralizantes produzidos após a vacinação. Porém, A validação foi desenhada de maneira mais direcionada as características particulares da metodologia, utilizando parâmetros e critérios de aceitação pertinentes, e as diretrizes aplicáveis dos órgãos citados acima. A validação proposta neste estudo apresentou resultados satisfatórios onde todos os parâmetros estabelecidos foram validados. Pode-se concluir que a RDC 27 é direcionada a bioensaios com característica cromatográfica e que os documentos dos demais órgãos também não apresentam uma aplicabilidade total. Na realidade é necessário que a ANVISA elabore um guia ou legislação de validação de metodologia que atenda as particularidades dos bioensaios utilizados nas pesquisas clínicas de vacinas para comprovação de imunogenicidade.
Vaccines are immunobiological products and are known to be safe, effective and with great participation in the control and / or eradication of immunopreventable diseases, proving that is an excelent cost benefit relation. Currently, Bio-Manguinhos is the main provider of vaccines for the Ministry of Health and to meet the demands of the National Immunization Program and uses as a strategy of supply, technology transfer agreements with global companies such as GlaxoSmithKline and Sanofi Pasteur, aiming to meet brazilian epidemiological demands and acquire technological development for the institution, configuring an innovative process of great relevance. The products generated through this process need to undergo Quality Control testing and clinical research to demonstrate the quality and therapeutic effectiveness through analytical and bioanalytical methods (bioassays) validated. This study aims to evaluate the applicability of the RDC 27 ANVISA and analyze other documents validation of bioassays recommended by WHO, FDA, USP and EMEA. For this, an analysis of these documents for verification of differences, similarities and application was done. A case study was performed through validation by reduction neutralization test for lysis plate for measles in 96-well plates (MICRO-PRNT) which is considered by the literature the most sensitive and specific method for qualification and quantification of neutralizing antibodies produced after vaccination. However, validation was designed in a more direct way to particular characteristics of the methodology, using parameters and acceptance criteria that are relevant and also applicable directives of the organs mentioned above. The validation proposed in this study showed satisfactory results where all parameters set were validated. It can be concluded that the RDC 27 is directed to bioassays with chromatographic characteristics and also that the documents of the other organs did not show an overall applicability. In reality, it is necessary that ANVISA prepares a guide or legislation of methodology validation that meets the particularities of bioassays used in clinical research of vaccines to prove the immunogenicity and also be useful for other bioassays with biological targets.
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Fratila, Mircea. "CONTRIBUTION A LA PRISE EN COMPTE DES PERTES FER DANS LA MODELISATION DES MACHINES ELECTRIQUES PAR ELEMENTS FINIS." Phd thesis, Université des Sciences et Technologie de Lille - Lille I, 2012. http://tel.archives-ouvertes.fr/tel-00836872.
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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).
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Lindqvist, Petter. "Validering av solida temperaturer i FDS genom jämförelse mot FE-beräkningar." Thesis, Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-79973.
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FDS (Fire Dynamics Simulator) använder en version av Navier-Stokes ekvationerna för att göra noggranna beräkningar av värme- och gastransport genom brandbelastade utrymmen. Utvecklarna av programmet arbetar kontinuerligt med att validera det allteftersom nya funktioner tillförs för att öka noggrannheten och bredda tillämpningsområdena. Väldigt lite av detta arbete fokuserar dock på FDS:s konduktionsmodell, den endimensionella Crank-Nicolson metoden. Det här examensarbetet ämnar därför undersöka noggrannheten i FDS:s konduktionsmodell genom jämförelse mot beräkningar med FEM (Finita elementmetoden). En FDS-modell skapades för att tillåta undersökning av en vägg och dess randvillkor med så liten påverkan från andra faktorer som möjligt. Detta för att skapa en kontrollerad omgivning som enkelt kunde replikeras i efterföljande FE-beräkningar av det konduktiva värmeflödet genom den solida obstruktionen. Tre väggar (10 cm betong, 20 cm betong och 1 mm stål) vardera med tre randvillkor (Exposed, Void och Insulated) utsattes för tre temperaturer (100 °C, 500 °C och 1000 °C) vilket ger 27 FDS simuleringar. Den adiabatiska yttemperaturen mättes i varje simulering och användes som indata till motsvarande FE-beräkningar. Resultatet påvisade inga signifikanta motsägelser vad gäller randvillkoren, med tillräcklig tid för termisk penetrering påverkade de den resulterande temperaturen som väntat. Undantaget var en mindre avvikelse i stålväggarna som utsattes för 100 °C och 500 °C med randvillkoren Exposed och Void där FDS aningen underskattade temperaturen relativt FE-beräkningarna. Gastemperaturerna i gridcellerna närmast väggen visade sig vara opålitliga. De tenderade att genomgå substantiella fluktuationer, troligen som ett resultat av hur FDS hanterar diskretiseringen av icke-solida volymer för Navier-Stokes beräkningarna. Dessa fluktuationer påverkade dock inte de resulterande solida temperaturerna eftersom medelgastemperaturen var korrekt. FDS påvisades även ha en tendens att aningen överskatta yttemperaturen under de första minuterna av simuleringarna relativt FE-beräkningarna. Temperaturerna från de två beräkningsmetoderna konvergerade dock efter några få minuter i samtliga tester. Dessa avvikelser ansågs ha för liten påverkan på de solida temperaturerna för att påvisa onoggrannhet i FDS. Därmed drogs slutsatsen att FDS:s beräkningar av temperaturer i solida material är tillräckligt noggranna inom dessa avgränsningar.FDS (Fire Dynamics Simulator) uses a version of the Navier-Stokes equations to make accurate calculations of heat and gas flow through enclosures exposed to fire. The developers of FDS have, and continue to, validate it as new features get added in an attempt to increase its accuracy and broaden its potential applications. However, little of this effort is focused on FDS’ conductive heat transfer model, based on the one-dimensional Crank-Nicolson method. Thus, this study aims to test the accuracy of FDS’ conduction model by comparing it to calculations using FEM (Finite Element Method). FDS simulations were created so as to facilitate the study of a wall and its boundary conditions with as little interference from other factors as possible. This to create a controlled environment which easily could be replicated in the subsequent FE-calculations of the conductive heat flow through the solid obstructions. Three different walls (10 cm concrete, 20 cm concrete and 1 mm steel), each with the three different boundary conditions for the rear surface (Exposed, Void and Insulated), were exposed to three different temperatures (100 °C, 500 °C and 1000 °C) for a total of 27 FDS simulations. The adiabatic surface temperature was measured in each simulation in FDS and used as input for the corresponding FE-calculations. The results showed no clear inconsistencies in the boundary conditions, given enough time for thermal penetration they affected the resulting temperatures as expected. Save a slight deviation in the steel walls exposed to 100 °C and 500 °C with boundary conditions Exposed and Void where FDS slightly underestimated the temperature relative to the FE-calculations. The gas temperatures in the grid cells closest to the wall were found to be unreliable as they tended to undergo substantial fluctuations, likely as a result of how FDS handles the discretization of non-solid space for the Navier-Stokes calculations. These fluctuations were however not found to affect the solid temperatures as the mean gas temperature was accurate. FDS was also found to have a tendency to slightly overestimate the surface temperature in the first few minutes of the simulations relative to the FE-calculations. Though the resulting temperatures from the two methods converged after a few minutes at most in all tests. These deviations were considered to have too minor an impact on the solid temperature to justify claims of inaccuracy in FDS. Thus, the general conclusion of this study is that FDS’ predictions of solid phase temperatures are sufficiently accurate within these delimitations.
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El, Makssoud Hassan. "Modélisation et Identification des Muscles Squelettiquessous Stimulation Electrique Fonctionnelle." Phd thesis, Université Montpellier II - Sciences et Techniques du Languedoc, 2005. http://tel.archives-ouvertes.fr/tel-00138186.
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Byström, Alexandra. "Compartment Fire Temperature Calculations and Measurements." Doctoral thesis, Luleå tekniska universitet, Byggkonstruktion och brand, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-59927.
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This thesis is devoted to heat transfer and fire dynamics in enclosures. It consists of a main part which summarizes and discusses the theory of heat transfer, conservation of energy, fire dynamics and specific fire scenarios that have been studied. In the second part of this thesis, the reader will find an Appendix containing seven scientific publications in this field. In particular, one- and two-zone compartment fire models have been studied. A new way of calculating fire temperatures of pre- and post-flashover compartment fires is presented. Three levels of solution techniques are presented including closed form analytical expressions, spread-sheet calculations and solutions involving general finite element temperature calculations. Validations with experiments have shown good accuracy of the calculation models and that the thermal properties of the surrounding structures have a great impact on the fire temperature development. In addition, the importance of the choice of measurement techniques in fire engineering has been studied. Based on the conclusions from these studies, the best techniques have been used in further experimental studies of different fire scenarios.Denna avhandling behandlar problem kopplade till värmeöverföring och branddynamik i slutna utrymmen med tonvikt på värmeöverföring mellan gaser och utsatta konstruktioner. Avhandlingen består av en huvuddel och ett appendix innehållande sju vetenskapliga artiklar. I huvuddelen sammanfattas och diskuteras grundläggande teorier och principer inom värmeöverföring och branddynamik samt studier av ett antal specialfall av brandscenarion som baseras på dessa teorier. I de avslutande bilagorna (Artiklar A1-A3 och Artiklar B1-B2) finns sju vetenskapliga artiklar som grundligare beskriver de ovan nämnda specialfallen. Huvudfokus i avhandlingen ligger på temperaturutveckling vid brand i slutna utrymmen. I avhandlingen studeras i synnerhet en- och två-zonsmodeller för brand i slutna utrymmen, och en ny metod för att beräkna brandgastemperaturer före och efter övertändning i rumsbränder är framtagen. Validering av dessa modeller med experiment visar att deras noggrannhet är bra. Modellerna visar också att de termiska egenskaperna hos de omgivande ytorna har stor inverkan på brandtemperatursutvecklingen. I tillägg studeras i denna avhandling betydelsen av val av mätmetoder i brandtekniska tillämpningar. På grundval av slutsatserna från dessa studier har de främsta mätteknikerna använts i ytterligare experimentella studier av olika brandscenarier.
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Pongpairote, Asia Nichackarn, and Mariam Bayat. "Arm Injury Prediction withTHUMS SAFER : Improvements of the THUMS SAFER upperextremity." Thesis, KTH, Lättkonstruktioner, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-290154.
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Globally, approximately 1.2 million people die each year due to trac accidents. Upperextremity injuries account for 18% to 25% of all car accident injuries. In order to beable to analyze these crash-related injuries, Human body models(HBMs) are used as acomplement to FE simulations. An example of a HBM is the THUMS SAFER that isbased on a 50 percentile American male. The aim of this study was to improve the upperextremity of the THUMS SAFER with respect to Autoliv's requirements to better predictfractures. In addition, this was validated against the Forman experiment(Forman, et al.,The journal of trauma and acute care surgery, vol. 77, 2014) where human cadavers ofthe upper extremity were axially impacted to replicate a car collision. This was done bygenerating the upper extremity geometry with segmentation of medical images of a righthuman hand in combination with the complete STL-geometry of the forearm from thePiper project. The STL-geometry of the segmented human hand and Piper forearm wasintegrated and a complete STL-geometry of the upper extremity was obtained. Basedon the complete STL-geometry, the FE-arm HEX 4.0 was built with modelling of bones,ligaments, soft tissue and skin with corresponding material choice in accordance withAutoliv's requirements.The model HEX 4.0 was improved considering an increased mesh density from an averageof 94% to 98%. HEX 4.0 was also validated against the data from the Forman experimentfor experiments 5, 6 and 15. It showed a good correlation with the acceleration curvesbetween the simulated and experimental values for the three experiments. The reactionforce in the elbow was compared for experiment 15, where the simulated value 5.7 kNdivided by a factor of 1.4 from 4 kN for the experiment. Furthermore, the rst principalstrains that occurred in HEX 4.0 were analysed by 17 ms were the highest accelerationwas achieved for experiments 5 and 6. Both experiments were shown to be close to thefailure threshold of bones. However, the highest value 5=9.8E-03 occurred in the radiusfor experiment 5, while 6=9.3E-03 in a ligament for experiment 6. In addition, thefailure threshold for experiment 15 exceeded 5 ms in lunate, schapoid and triquetrum.This indication of fractures is in good agreement with the experimental results where thecorresponding bones resulted in fractures in experiment 15. HEX 4.0 was an improvedupper extremity of the THUMS SAFER considering an increased mesh density. It isalso capable of indicating fractures and corresponding positions in the form of analyzesof occurring stresses and strains. Nevertheless, improvements and further validation ofHEX 4.0 has been proposed in the future work section.Globalt, dör varje ar ungefär 1.2 miljoner personer på grund av trafikolyckor. Övre extremit skador utgör 18% till 25% av alla skador inom bilolyckor. För att kunna analysera dessa krockrelaterade skador används humanmodeller (HBM) som komplement för FE-simuleringar. Ett exempel på en HBM är THUMS SAFER som är baserad på en 50 percentile amerikans man. Målet med denna studie är att förbättra uppre extremiten av THUMS SAFER med avseende på Autolivs krav för att bättre kunna förutspå frakturer Dessutom validerades detta mot Forman experiment (Forman, et al., The journal of trauma and acute care surgery, vol. 77, 2014) där övre extremitet av människokadaver blev axiellt påverkade för att replikera en bil kollsion. Detta gjordes genom att generera STL-geometrin av den övre extremitet med segmentering av medicinska bilder av en höger människohand i kombination med färdig STL-geometri av underarmen från Piperprojektet STL-geometrin av den segmenterande människohanden och Piper underarmen integrerades och en komplett STL-geometri av övre extremiteten erhölls. Baserad på den kompletta STL-geometrin byggdes FE-armen HEX 4.0 med modellering av ben, ligament, mjukvävnad samt hud med motsvarande materialval i enighet med Autolivs krav. Modellen HEX 4.0 förbättrades i form av en ökad mesh densitet från medelvärdet 94% till 98%. Den validerades även gentemot data från Forman experimentet för experiment5, 6 och 15. Det påvisade en god korrelation på accelerations kurvorna mellan de simulerade och experimentella värdena för de tre experimenten. Reaktionskraften i armbågen jämfördes för experiment 15 där den simulerade värdet 5.7 kN skiljde sig med en faktor 1.4 från 4 kN för experimentet. Ytterligare analyserades första huvudtöjningarna som uppkom i HEX 4.0 vid 17 ms, då den högsta accelerationen uppnåddes för experiment 5 och 6. Det visades att båda experimenten låg nära failure tröskeln av ben, däremot uppkom den högsta värdet 5=9.8E-03 i radius för experiment 5, medan 6=9.3E-03 i ett ligament för experiment 6. Dessutom överskred failure tröskeln för experiment 15 efter 5 ms i lunate, schapoid och triquetrum. Denna indikation av frakturer stämmer väl medexperiment resultaten där motsvarande benen resulterande i frakturer i experiment 15.HEX 4.0 är en förbättrad övre extremitet av THUMS SAFER i form av förbättrad mesh densitet. Den är även kapabel att indikera frakturer och motsvarande position i form av analyser på förekommande spänningar och töjningar. Förbättringar och ytterligare validering av HEX 4.0 föreslås för framtida arbete.
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Bayat, Mariam, and Nichakarn Pongpairote. "Arm Injury Prediction with THUMS SAFER: Improvements of the THUMS SAFER upper extremity." Thesis, KTH, Hållfasthetslära, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-284465.
Full textAbstract:
Globally, approximately 1.2 million people die each year due to traffic accidents. Upper extremity injuries account for 18% to 25% of all car accident injuries. In order to be able to analyze these crash-related injuries, Human body models(HBMs) are used as a complement to FE simulations. An example of a HBM is the THUMS SAFER that is based on a 50 percentile American male. The aim of this study was to improve the upper extremity of the THUMS SAFER with respect to Autoliv's requirements to better predict fractures. In addition, this was validated against the Forman experiment(Forman, et al., The journal of trauma and acute care surgery, vol. 77, 2014) where human cadavers of the upper extremity were axially impacted to replicate a car collision. This was done by generating the upper extremity geometry with segmentation of medical images of a right human hand in combination with the complete STL-geometry of the forearm from the Piper project. The STL-geometry of the segmented human hand and Piper forearm was integrated and a complete STL-geometry of the upper extremity was obtained. Based on the complete STL-geometry, the FE-arm HEX 4.0 was built with modelling of bones, ligaments, soft tissue and skin with corresponding material choice in accordance with Autoliv's requirements. The model HEX 4.0 was improved considering an increased mesh density from an average of 94% to 98%. HEX 4.0 was also validated against the data from the Forman experiment for experiments 5, 6 and 15. It showed a good correlation with the acceleration curves between the simulated and experimental values for the three experiments. The reaction force in the elbow was compared for experiment 15, where the simulated value 5.7 kN divided by a factor of 1.4 from 4 kN for the experiment. Furthermore, the fi rst principal strains that occurred in HEX 4.0 were analysed by 17 ms were the highest acceleration was achieved for experiments 5 and 6. Both experiments were shown to be close to the failure threshold of bones. However, the highest value e5=9.8E-03 occurred in the radius for experiment 5, while e6=9.3E-03 in a ligament for experiment 6. In addition, the failure threshold for experiment 15 exceeded 5 ms in lunate, schapoid and triquetrum. This indication of fractures is in good agreement with the experimental results where the corresponding bones resulted in fractures in experiment 15. HEX 4.0 was an improved upper extremity of the THUMS SAFER considering an increased mesh density. It is also capable of indicating fractures and corresponding positions in the form of analyzes of occurring stresses and strains. Nevertheless, improvements and further validation of HEX 4.0 has been proposed in the future work section.Globalt, dör varje år ungefär 1.2 miljoner personer på grund av trafi kolyckor. Skador på övre extremitet utgör 18% till 25% av alla skador inom bilolyckor. För att kunna analysera dessa krockrelaterade skador används humanmodeller(HBM) som komplement för FE-simuleringar. Ett exempel på en HBM är THUMS SAFER som är baserad på en "50 percentile" amerikans man. Målet med denna studie är att förbättra över extremiten av THUMS SAFER med avseende på Autolivs krav för att bättre kunna förutspå frakturer. Dessutom validerades detta mot Forman experiment(Forman, et al., The journal of trauma and acute care surgery, vol. 77, 2014) där övre extremitet av människokadaver blev axiellt påverkade för att replikera en bilkollsion. Detta gjordes genom att generera STL-geometrin av en övre extremitet med segmentering av medicinska bilder av en höger människohand i kombination med färdig STL-geometri av underarmen från Piper projektet. STL-geometrin av den segmenterande människohanden och Piper underarmen integrerades och en komplett STL-geometri av övre extremiteten erhölls. Baserad på den kompletta STL-geometrin byggdes FE-armen HEX 4.0 med modellering av ben, ligament, mjukvävnad samt hud med motsvarande materialval i enighet med Autolivs krav. Modellen HEX 4.0 förbättrades i form av en ökad mesh densitet från medelvärdet 94% till 98%. Den validerades även gentemot data från Forman experimentet för experiment 5, 6 och 15. Det påvisade en god korrelation på accelerations kurvorna mellan de simulerade och experimentella värdena för de tre experimenten. Reaktionskraften i armbågen jämfördes för experiment 15 där den simulerade värdet 5.7 kN skiljde sig med en faktor 1.4 från 4 kN för experimentet. Ytterligare analyserades första huvudtöjningarna som uppkom i HEX 4.0 vid 17 ms, då den högsta accelerationen uppnådes för experiment 5 och 6. Det visades att båda experimenten låg nära gränsen för benfraktur, däremot uppkom det högsta värdet e5=9.8E-03 i radius för experiment 5, samt e6=9.3E-03 i ett ligament för experiment 6. Dessutom överskred gränsen för benfrakturer för experiment 15 efter 5 ms i lunate, schapoid och triquetrum. Denna indikation av frakturer stämmer väl med resultatet av experimentet där motsvarande benen resulterades i frakturer i experiment 15. HEX 4.0 är en förbättrad övre extremitet av THUMS SAFER i form av förbättrad meshdensitet. Den är även kapabel att indikera frakturer och motsvarande position i form av analyser på förekommande spänningar och töjningar. Förbättringar och ytterligare validering av HEX 4.0 föreslås för framtida arbete.
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Colombiano, Jérémy. "Approche multi-échelle pour la caractérisation de la réaction au feu sur un matériau bois. Développement d'une méthodologie pour l'ingénierie de la sécurité incendie. Validation of a Pyrolysis Model of Wood Thermal Decomposition under Cone Calorimeter." Thesis, Chasseneuil-du-Poitou, Ecole nationale supérieure de mécanique et d'aérotechnique, 2020. http://www.theses.fr/2020ESMA0017.
Full textAbstract:
De plus en plus, les études de sécurité incendie reposent sur l’ingénierie de la sécurité incendie. Il s’agit notamment à l’aide de codes de calcul, de réaliser des simulations numériques visant à définir les règles de sécurité à appliquer. Ainsi, des nombreuses études ont permis d’améliorer les codes de calcul et de définir les bases et guides techniques à respecter pour la réalisation de ces études. Toutefois, si cela est vrai pour le domaine de la résistance au feu, de l’évacuation ou du désenfumage, ce n’est pas encore le cas dans le domaine de la réaction au feu. Cette dernière représente la manière dont le matériau va se comporter comme combustible et elle caractérise l’aptitude de ce matériau à s’enflammer et à contribuer à un incendie.Dans ce contexte, l’objectif de ces travaux de thèse est d’étudier et de prédire la cinétique de décomposition thermique, la combustion et la propagation de flamme d’un matériau bois. Pour cela, la méthode de travail retenue est multi-échelle, à la fois expérimentale et numérique. Cette approche permet dans un premier temps de simplifier les phénomènes dans le but de déterminer les propriétés du matériau, puis d’ajouter de la complexité à échelle croissante, afin d’identifier les processus pilotant la propagation de flamme et de définir les bases pour une étude d’ingénierie. Au total, 4 échelles de travail ont été étudiées :- A petite échelle, concernant uniquement la phase solide. Elle permet d’extraire certaines propriétés du matériau en travaillant sur des échantillons de l’ordre du milligramme. Les propriétés extraites sont les propriétés thermiques et cinétiques, indispensables pour caractériser l’échauffement et la décomposition thermique du matériau à échelle plus grande.- A moyenne échelle, incluant l’influence de la phase gazeuse avec notamment le développement de la flamme à la surface de l’échantillon. Les échantillons sont de l’ordre de la centaine de gramme avec une épaisseur identique à l’application finale du produit. L’objectif est dans un premier temps d’identifier les paramètres de combustion du matériau, tels que la chaleur de combustion, le taux de formation de suie, de monoxyde de carbone, etc. Dans un second temps, il a s’agit de valider numériquement l’ensemble des propriétés ainsi extraites (propriétés thermiques, cinétiques et de combustion) par comparaison avec les données expérimentales (taux de dégagement de chaleur, perte de masse, températures, etc.).- A échelle intermédiaire, utilisant des échantillons de l’ordre du kilogramme. Elle tient compte de la propagation de flamme à la surface de l’échantillon. De ce fait, les processus pilotant cette propagation sont étudiés. Cette échelle permet d’évaluer l’aptitude du code à prédire la cinétique de propagation de flamme. Deux modes de propagation sont investigués : contre-courant et co-courant. Cette échelle permet également d’établir certaines bases pour la réalisation d’étude d’ingénierie de réaction au feu.- A échelle finale, couplant les deux modes de propagation étudiés. L’objectif est alors de valider les observations faites à l’échelle précédente et d’étayer les bases pour une étude d’ingénierieIncreasingly, fire safety relies on fire safety engineering. This involves, in particular, using calculation codes, performing numerical simulations aimed at defining the safety rules to be applied. Thus, numerous studies have made it possible to improve the calculation codes and define the bases and technical guides to be respected for carrying out these studies. However, while this is true in the field of fire resistance, evacuation or smoke control, it is not yet the case in the field of reaction to fire. The latter represents how the material will behave as a fuel and it characterizes the ability of that material to ignite and contribute to a fire.In this context, the objective of this thesis work is to study and predict the kinetics of thermal decomposition, combustion and flame propagation of wood material. For this, the working method adopted is multi-scale, both experimental and digital. This approach allows initially to simplify the phenomena in order to determine the properties of the material, then to add complexity on an increasing scale, in order to identify the processes controlling the propagation of flame and to define the bases for an engineering study. In total, 4 working scales were studied:- At a small scale, which concerns only the solid phase. It permits to extract some properties of the material by working on samples of the order of a milligram. The properties extracted are the thermal and kinetic properties, essential to characterize the heating and thermal decomposition of the material on a larger scale.- At medium scale, including the influence of the gas phase within particularly the development of the flame on the surface of the sample. The samples are of the order of a hundred grams with a thickness identical to the final application of the product. The objective is first to identify the combustion parameters of the material, such as the heat of combustion, the rate of formation of soot, carbon monoxide, etc. Secondly, it concerns the numerical validation of all the properties extracted (thermal, kinetic and combustion properties) by comparison with the experimental data (rate of heat release, loss of mass, temperatures, etc. ).- At the intermediate scale, using samples of the order of one kilogram. It takes into account the propagation of flame on the surface of the sample. Therefore, the processes driving this propagation are studied. This scale is used to assess the ability of the code to predict the kinetics of flame propagation. Two modes of propagation are investigated: counter-current and co-current. This scale also makes it possible to establish certain bases for carrying out a reaction to fire engineering study.- At final scale, two studied modes of propagation are coupled. The objective is then to validate the observations made at the previous scale and to support the basis for an engineering study
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Mekki, Ahmed. "Contribution à la Spécification et à la Vérification des Exigences Temporelles : Proposition d’une extension des SRS d’ERTMS niveau 2." Thesis, Ecole centrale de Lille, 2012. http://www.theses.fr/2012ECLI0006/document.
Full textAbstract:
Les travaux développés dans cette thèse visent à assister le processus d’ingénierie des exigences temporelles pour les systèmes complexes à contraintes de temps. Nos contributions portent sur trois volets : la spécification des exigences, la modélisation du comportement et la vérification. Pour le volet spécification, une nouvelle classification des exigences temporelles les plus communément utilisées a été proposée. Ensuite, afin de cadrer l’utilisateur durant l’expression des exigences, une grammaire de spécification à base de motifs prédéfinis en langage naturel est développée. Les exigences générées sont syntaxiquement précises et correctes quand elles sont prises individuellement, néanmoins cela ne garantie pas la cohérence de l’ensemble des exigences exprimées. Ainsi, nous avons développé des mécanismes capables de détecter certains types d’incohérences entre les exigences temporelles. Pour le volet modélisation du comportement, nous avons proposé un algorithme de transformation des state-machine avec des annotations temporelles en des automates temporisés. L’idée étant de manipuler une notation assez intuitive et de générer automatiquement des modèles formels qui se prêtent à la vérification. Finalement, pour le volet vérification, nous avons adopté une technique de vérification à base d’observateurs et qui repose sur le model-checking. Concrètement, nous avons élaboré une base de patterns d’observation (ou observateurs) ; chacun des patterns développés est relatif à un type d’exigence temporelle dans la nouvelle classification. Ainsi, la vérification est réduite à une analyse d’accessibilité des états correspondants à la violation de l’exigence associéeThe work developed in this thesis aims to assist the engineering process of temporal requirements for time-constrained complex systems. Our contributions concern three phases: the specification, the behaviour modelling and the verification. For the specification of temporal requirements, a new temporal properties typology taking into account all the common requirements one may meet when dealing with requirements specification, is introduced. Then, to facilitate the expression, we have proposed a structured English grammar. Nevertheless, even if each requirement taken individually is correct, we have no guarantee that a set of temporal properties one may express is consistent. Here we have proposed an algorithm based on graph theory techniques to check the consistency of temporal requirements sets. For the behaviour modelling, we have proposed an algorithm for transforming UML State Machine with time annotations into Timed Automata (TA). The idea is to allow the user manipulating a quite intuitive notation (UML SM diagramsduring the modelling phase and thereby, automatically generate formal models (TA) that could be used directly by the verification process. Finally, for the verification phase, we have adopted an observer-based technique. Actually, we have developed a repository of observation patterns where each pattern is relative to a particular temporal requirement class in our classification. Thereby, the verification process is reduced to a reachability analysis of the observers’ KO states relatives to the requirements’ violation
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Laplanche, Karine. "Etude du comportement au feu des assemblages de structures bois : approche expérimentale et modélisation." Phd thesis, Université Blaise Pascal - Clermont-Ferrand II, 2006. http://tel.archives-ouvertes.fr/tel-00693999.
Full textAbstract:
Cette étude consiste en l'élaboration d'un modèle éléments finis tridimensionnel décrivant le comportement des assemblages brochés et boulonnés des structures bois sous actions thermiques. Ce modèle intègre les champs de températures dans un modèle mécanique non linéaire. La validation du modèle réalisé à l'aide d'essais est faite en trois étapes : la validation mécanique à froid, celle thermique et celle thermomécanique. Après validation, le comportement des assemblages brochés unitaires est modélisé pour différentes durées d'exposition au feu. Enfin, la modélisation d'assemblages multiples met en évidence la caractérisation du nombre effectif en fonction des champs thermiques.
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Mohamed, Drissi. "Un modèle de propagation de feux de végétation à grande échelle." Phd thesis, Université de Provence - Aix-Marseille I, 2013. http://tel.archives-ouvertes.fr/tel-00931806.
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Le présent travail est consacré au développement et à la validation d'un modèle hybride de propagation d'un incendie de végétation à grande échelle prenant en compte les hétérogénéités locales liées à la végétation, à la topographie du terrain et aux conditions météorologiques. Dans un premier temps, on présente différentes méthodes permettant de générer un réseau amorphe, représentatif d'une distribution réaliste de la végétation. Le modèle hybride est un modèle de réseau où les phénomènes qui se produisent à l'échelle macroscopique sont traités de façon déterministe, comme le préchauffage du site végétal provenant du rayonnement de la flamme et des braises et de la convection par les gaz chauds, mais aussi son refroidissement radiatif et son inflammation pilotée. Le rayonnement thermique provenant de la flamme est calculé en combinant le modèle de flamme solide à la méthode de Monte Carlo et en considérant son atténuation par la couche d'air atmosphérique entre la flamme et la végétation réceptive. Le modèle est ensuite appliqué à des configurations simples de propagation sur un terrain plat ou incliné, en présence ou non d'un vent constant. Les résultats obtenus sont en bon accord avec les données de la littérature. Une étude de sensibilité a été également menée permettant d'identifier les paramètres les plus influents du modèle, en termes de vitesse de propagation du feu, et de les hiérarchiser. La phase de validation a portée sur l'analyse comparative des contours de feux calculés par le modèle avec ceux mesurés lors d'un brûlage dirigé réalisé en Australie et d'un feu réel qui a lieu en Corse en 2009, montrant un très bon accord en termes de vitesse de propagation, de contours de feu et de surface brûlée.
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Hart, M. J. Alexandra. "Action in Chronic Fatigue Syndrome: an Enactive Psycho-phenomenological and Semiotic Analysis of Thirty New Zealand Women's Experiences of Suffering and Recovery." Thesis, University of Canterbury. Social and Political Sciences, 2010. http://hdl.handle.net/10092/5294.
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This research into Chronic Fatigue Syndrome (CFS) presents the results of 60 first-person psycho-phenomenological interviews with 30 New Zealand women. The participants were recruited from the Canterbury and Wellington regions, 10 had recovered. Taking a non-dual, non-reductive embodied approach, the phenomenological data was analysed semiotically, using a graph-theoretical cluster analysis to elucidate the large number of resulting categories, and interpreted through the enactive approach to cognitive science.
The initial result of the analysis is a comprehensive exploration of the experience of CFS which develops subject-specific categories of experience and explores the relation of the illness to universal categories of experience, including self, ‘energy’, action, and being-able-to-do.
Transformations of the self surrounding being-able-to-do and not-being-able-to-do were shown to elucidate the illness process.
It is proposed that the concept ‘energy’ in the participants’ discourse is equivalent to the Mahayana Buddhist concept of ‘contact’. This characterises CFS as a breakdown of contact. Narrative content from the recovered interviewees reflects a reestablishment of contact.
The hypothesis that CFS is a disorder of action is investigated in detail.
A general model for the phenomenology and functional architecture of action is proposed. This model is a recursive loop involving felt meaning, contact, action, and perception and appears to be phenomenologically supported.
It is proposed that the CFS illness process is a dynamical decompensation of the subject’s action loop caused by a breakdown in the process of contact.
On this basis, a new interpretation of neurological findings in relation to CFS becomes possible. A neurological phenomenon that correlates with the illness and involves a brain region that has a similar structure to the action model’s recursive loop is identified in previous research results and compared with the action model and the results of this research. This correspondence may identify the brain regions involved in the illness process, which may provide an objective diagnostic test for the condition and approaches to treatment.
The implications of this model for cognitive science and CFS should be investigated through neurophenomenological research since the model stands to shed considerable light on the nature of consciousness, contact and agency.
Phenomenologically based treatments are proposed, along with suggestions for future research on CFS. The research may clarify the diagnostic criteria for CFS and guide management and treatment programmes, particularly multidimensional and interdisciplinary approaches.
Category theory is proposed as a foundation for a mathematisation of phenomenology.
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Jeyasingh, Vinoj Meshach Aaron. "Analytical modeling of metallic honeycomb for energy absorption and validation with FEA." Diss., 2005. http://hdl.handle.net/10057/732.
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Honeycomb materials possess high energy absorption characteristics and are useful for the impact protection of structural members. Various honeycomb configurations are being developed for a variety of applications. Analytical models are now available to determine the energy absorption characteristics of the regular hexagonal type of honeycomb. However, the development a parameterized analytical model that can determine the energy absorption characteristics of various honeycomb shapes is needed. In this research, a parameterized analytical model is developed for the typical honeycomb shape, and is validated using experimental and finite element analysis. Honeycomb materials exhibit strain-rate effects at impact velocities. They can have higher energy absorption during dynamic crush than during quasi-static crush. In order to determine the energy absorption of honeycomb material at higher velocity, the characterization of it must be made using high-impact testing machines, which are expensive and time-consuming. Therefore, development of an analytical model that can predict energy absorption at higher velocities is needed. Also, strain-rate coefficients must be determined for each particular type of honeycomb since the strain rate depends on the geometrical properties of the honeycomb. Therefore, strain-rate coefficients were developed for each honeycomb model in this research. The energy absorption of honeycombs at higher impact velocities was also determined using the low-velocity test, which will be useful when only low-velocity machines are available for testing honeycombs. Finally, a performance analysis was carried out using response surface methods to maximize energy absorption of the honeycomb.Thesis (Ph.D.)--Wichita State University, College of Engineering, Dept. of Mechanical Engineering
"May 2005."
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Yi-TingLi and 李羿霆. "Design and Validation of Brushless Doubly-fed Generators for Wind Turbines." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/88319119933967017423.
Full textAbstract:
碩士國立成功大學
系統及船舶機電工程學系碩博士班
101
This thesis proposes a design process for brushless doubly-fed induction machine (BDFIM) applied to wind turbines. The specification of the wind turbine generator is determined for Taiwan’s low wind conditions. An accurate magnetic circuit model (MCM) is constructed for BDFIM. The model can rapidly calculate the dimension of BDFIM by taking saturation into account and calculate the machine parameters without time-consuming finite element analysis (FEA). By combining the MCM and an equivalent circuit model (ECM), the BDFIM can be properly designed. A scaled-down prototype is realized and tested to verify the models accuracy and validate the feasibility of the BDFIM design approach. According to the experimental and FEA simulation results, the design process can achieve the prescribed specifications. The developed model can be farther used for design of BDFIM for any wind conditions.
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Chi-ju, Hwa, and 華紀如. "Validation of Persuasive Effects of Fear Appeals Based on the Ordered Protection Motivation Model." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/42793606969714277955.
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碩士大同工學院
事業經營研究所
86
Marketing communications are designed to influence attitude and behavior. The fear appeal, a message that attempts to influence behavior through the threat of some danger, is one such type of marketing communication. The power of such appeals seems obvious; all that should be required to influence an individual''s behavior is to make that person aware of the danger or dangerous behavior. Marketers have attempted to take advantage of this relationship by using the threat of danger to evoke the emotional response of fear and thus influence behavior.To date, research has not given marketers much help in understanding the effect of fear on behavior. Research to provide communication guidelineshas produced conflicting results. Past research efforts have been unable to provide sound theory for the process of influencing behavior through fear.Then, Tanner et al. (1991) suggested that fear arousal in response to a threat message would be necessary for changes in attitude and behavior.Besides, Bandura (1977) in related work on self-efficacy, theorized that effective coping defenses prohibit fear arousal. Self-efficacy is the perception of one''s ability to perform a specific behavior. In addition, Rogers (1983) supported the effects of self-efficacy information in influencing behaviors. Therefore, in this study, using the two variables to provide effective suggestions that can be used by health care practitioners to promote responsible sexual practices.The study involved the topic of sexually transmitted diseases (STDs).The experimental treatments were administered in a 2X2X2X2 between-subjects factorial experimental design as follows: 1. Severity of threat (low/high). 2. Self-efficacy (low/high). 3. Perceived social costs (low/high). 4. Gender (male/female) The different degrees of threat and self-efficacy were selected by pretest.Subjects were 240 students of Tatung Institute of Technology, approximately equal in number by gender. According to the experiment results, we obtained the following conclusions: 1. Faced with high threat ad, subjects have higher fear emotional response, better attitude toward the ad, and higher behavior intentions than low threat ad. 2. Fear emotional response can affect behavioral intentions positively. 3. Subjects with high self-efficacy, have better attitude toward the ad and higher behavioral intentions than those with self-efficacy. 4. When subjects'' perceived social costs are high, they may be reluctant to use the recommended behavior. Consequently, lower attitude toward the ad and behavioral intentions will be occur. 5. In the topic of sexually transmitted diseases (STD), since females are physically unable to be solely responsible for adopting the recommended behavior (i.e., using condoms), they have less control over implementation.Therefore, females have worse attitude toward the ad and lower behavioral intentions than males.
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Oyarzun, Laura Cristina. "Graph-matching and FEM-based Registration of Computed Tomographies for Outcome Validation of Liver Interventions." Phd thesis, 2016. http://tuprints.ulb.tu-darmstadt.de/5270/1/disstemplate.pdf.
Full textAbstract:
Liver cancer is one of the leading causes of death worldwide. One of the reasons for that is the high tumor recurrence rate. The only way to reduce the recurrence rate is to ensure that all carcinogenic cells are destroyed after intervention. Unfortunately, the information available to assess the outcome of an intervention is limited. In the clinical routine, a pair of pre- and post-operatively gathered computed tomographies (CT) of the abdomen are typically compared to decide whether the patient needs further treatment. However, the post-operative liver will be deformed due to breathing and intervention which will complicate the comparison task by simple inspection of both images.
The results presented in this thesis will support the physician during the outcome validation process after minimally invasive interventions and open liver surgeries. Therefore, the physician is provided with qualitative measures and visualizations that support him in the decision making task. The basis of a reliable outcome validation is an accurate non-rigid registration method.
This thesis proposes to combine internal correspondences at vessel ramifications and landmarks at the surface of the organ to increase the accuracy of the registration results. The internal correspondences are the result of a novel efficient and fully automatic graph matching method. Landmarks at the surface of the liver are given by a method that detects the organs that are adjacent to it at each surface point. Both types of landmarks are incorporated in a FEM-based registration. The registration method has been tested in 25 pairs of pre- and post-operative clinical CT images achieving an average accuracy of 1.22 mm and a positive predictive value of 0.95.
In consequence of the accuracy obtained with the proposed methods the physician is able to determine with certainty if the outcome of the intervention was satisfactory. Hence, he can without delay decide to re-treat the patient if needed to remove the remnant tumor. This fast response could at the end reduce the tumor recurrence rate.