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Efeitos imediatos de um esforço submáximo sobre a velocidade de onda de pulso em pacientes com Síndrome de Marfan / Immediate effects of submaximal effort on pulse wave velocity in patients with Marfan syndromePeres, Paulo Alberto Tayar [UNIFESP] 26 May 2010 (has links) (PDF)
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Publico-068.pdf: 848593 bytes, checksum: faea7296d3b3e87c6a1212049c181df8 (MD5) / Introdução: A Síndrome de Marfan (SM) é uma doença de herança autossômica dominante decorrente de mutações no gene da fibrilina 1 no cromossomo 15, e pode apresentar manifestações esqueléticas, oculares, cardiovasculares entre outras. A velocidade de onda de pulso(VOP) é utilizada como um índice da elasticidade e rigidez arterial e está relacionada as propriedades elásticas da parede vascular. A pratica de exercício é limitada para esta população. Objetivo: Avaliar o efeito agudo de exercício submáximo em pacientes portadores de SM sem dilatação da aorta ou no máximo com dilatação leve deste vaso e o comportamento das variáveis fisiológicas. Casuística e Método: A VOP e variáveis fisiológicas foram avaliadas antes e após a realização de um esforço submáximo em 33 pacientes com SM e 18 controles. Resultados: A VOP no grupo com SM foi de 8,51±0,58 m/s no repouso e de 9,10±0,63 m/s ao final do exercício (p=0,002) e no grupo controle de 8,07±0,35 m/s no repouso e 8,98±0,56 m/s ao final (p=0,004). A análise comparativa da VOP entre os grupos controle e os pacientes com SM no repouso (p=0,519) e ao final do esforço (p=0,866) não se mostrou diferente. Os valores finais da freqüência cardíaca do grupo controle ficaram 10% acima dos indivíduos com SM (p = 0,01). A pressão arterial sistólica final foi superior no grupo controle (p=0,02). O lactato não se mostrou diferente e o tempo de exercício foi superior no grupo controle(p=0,01). Conclusão: O comportamento da distensibilidade aórtica foi semelhante, nos pacientes com SM sem ou com dilatação leve da aorta, ao grupo controle. Todavia as respostas cronotrópicas e pressóricas foram inferiores. / Purpose: Marfan syndrome is a dominant autosomal disease provoked by mutations of gene of fibrillin 1, chromosome 15, and may exhibit skeletal, ocular, cardiovascular and other manifestations. Pulse wave velocity (PWV) is used as a measure of arterial elasticity and rigidity and is related to the elastic properties of the vascular wall. As the practice of exercise is limited in this population, it was of our interest to analyze the acute effect of moderate to intensive exercise on patients with Marfan syndrome with either no dilatation of the aorta or a maximum of mild dilatation of this vessel. Methods: PWV and physiological variables were evaluated before and after the performance of sub-maximal exercise in 33 patients with Marfan syndrome and 18 controls. Results: PWV in the group with Marfan syndrome was 8.51±0.58 m/s at rest and 9.10±0.63 m/s at the end of the exercise (p=0.002); in the control group, PWV was 8.07±0.35 m/s at rest and 8.98±0.56 m/s at the end of exercise (p=0.004). The comparative analysis between groups regarding PWV at rest (p=0.519) and at the end of exercise (p=0.866) revealed no statistically significant differences. The final heart rate values in the control group were 10% higher than values in the group with Marfan syndrome (p = 0.01). Final systolic arterial pressure was higher in the control group (p=0.02). There was no difference in lactate between groups. Exercise time was greater in the control group (p=0.01). Conclusions: The behavior of aortic distensibility was similar in the patients with Marfan syndrome without or with mild dilatation of the aorta to that of the control group. The chronotropic and pressure responses were lower in patients than in control group. / TEDE / BV UNIFESP: Teses e dissertações
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Planification pour la gestion autonomique de l'élasticité d'applications dans le cloud / Model and mechanisms to support the elasticity of distributed applications in the cloudLetondeur, Loic 31 October 2014 (has links)
Le Cloud Computing permet une optimisation des coûts de déploiement et de maintenance des applications. Grâce au cloud, celles-ci peuvent être déployées et reconfigurées en l'espace de quelques minutes. La nécessité pour une application d'être en permanence à la juste taille afin que celle-ci maintienne continuellement une qualité de service suffisante sans pour autant utiliser trop de ressources, requiert de mettre en place l'élasticité des applications dans le cloud. Cependant, l'état de l'art montre que les solutions actuelles de gestion de l'élasticité sont restreintes à des applications multi-tiers tout en limitant fortement les scénarios possibles. Le cloud est effectivement un paradigme jeune et les différents acteurs du marché ont rapidement cherché à offrir l'élasticité. Si cette élasticité présente l'avantage indéniable d'apporter une mise place rapide et simple de l'élasticité, celle-ci n'obéit pas aux besoins de nombreux utilisateurs.Afin de repousser les limites actuelles de l'élasticité, les travaux présentés dans ce manuscrit proposent un outil de spécification de l'élasticité nommé Vulcan. A la fois simple et complet, Vulcan montre qu'il n'existe pas de corrélation entre la complétude de la solution et la complexité de son utilisation. Basé sur une approche autonomique, Vulcan apporte les contributions suivantes : - un modèle d'applications élastiques : celui-ci permet de décrire selon un mode dit "par intention", la façon dont l'application doit évoluer au cours des reconfigurations induites par l'élasticité. Le formalisme de ce modèle est à la base de la simplicité recherchée quant à l'utilisation de la solution.- un algorithme de planification : cet algorithme permet la résolution des différents paramètres lors de l'élasticité tout en offrant une compréhension simple à l'utilisateur de Vulcan.- un prototype qui met en oeuvre l'ensemble des concepts mis en avant dans ce document.Reposant sur des principes à la fois novateurs mais également issus de solutions éprouvées, des expérimentations ont démontré tant les capacités d'intégration de Vulcan vis-à-vis de l'existant, que la viabilité des concepts proposés ou le potentiel de l'approche. Il en ressort une solution générique, sans restriction quant aux applications gérées et qui repousse les limites actuelles en matière d'élasticité. / Cloud computing permits cost optimization of both deployment and maintenance applications. Thanks to the cloud, applications can be deployed and reconfigured in a few minutes. Each application can thus be continuously maintained at a fair size, so that it can continuously maintain a sufficient quality of service without using too many resources. This adaptation is achieved thanks to the feature named « elasticity ». However, the state of the art shows that current solutions for the management of elasticity are restricted to multi-tier applications and do not manage all possible scenarios. The cloud is actually a young paradigm and the various market providers manage to offer elasticity. If the provided elasticity has the undeniable advantage of being a fast and easy mean to manage basic cases, it does not address the needs of many users.To tackle the current limits of elasticity, the work presented in this manuscript propose a tool for the specification of elasticity that is named Vulcan. Besides being simple and complete, Vulcan shows that there is no correlation between the completeness of a solution for the management of elasticity and the complexity of its use. Based on an autonomous approach, Vulcan brings the following contributions :- a model for elastic applications : it is used to describe how an application should evolve over the reconfigurations induced during elasticity. This description is done at a high level said « by intension » thanks to an innovative formalism. The proposed formalism is at the basis of the Vulcan simplicity of use.- a scheduling algorithm : this algorithm resolves various parameters during elasticity while providing to the user of Vulcan an easy comprehension. - a prototype that implements all of the concepts described in this manuscript.Making use of both innovative concepts and principles from proven solutions, Vulcan has shown its capabilities to push the current limits of elasticity.
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Estimativa econométrica das elasticidades renda e preço da demanda por gás natural para o setor industrial brasileiro / Econometric Forecasts: A Study on Long-Term Price and Income Elasticity for Natural Gas in the Brazilian Industrial SectorRenata Fonseca Cabral 11 June 2013 (has links)
Este trabalho tem como objetivo estimar a elasticidade renda e preço da demanda por gás natural no Brasil para o setor industrial brasileiro. O segmento de consumo industrial representa cerca de dois terços do consumo de gás natural no país, destacando sua importância estratégica na elaboração de política energética relacionada ao gás. Este trabalho apresenta também o incremento nas trocas internacionais de gás natural e a perspectiva de aumento do uso desse energético no Brasil e no mundo. Alguns desafios ainda se colocam para a efetiva globalização dessa indústria, como: a necessidade de realização de investimentos em infraestrutura de produção, transporte e distribuição; o aprimoramento do acesso às principais reservas do hidrocarboneto; e as incertezas com relação à evolução da demanda. Utiliza-se o estudo estatístico econométrico para estimar as elasticidades preço e renda, ou seja, para investigar como a demanda industrial brasileira reage frente a um aumento ou diminuição de preço do gás e das variações na renda disponíveis no Brasil. Como proxy da renda industrial utilizam-se os dados do PIB industrial brasileiro. Após identificar que as séries estudadas eram não estacionárias, optou-se pela utilização do conceito de cointegração. Os resultados obtidos por meio do referido modelo mostraram que a demanda estudada é muito mais sensível a variações do preço do gás natural do que a variações na renda. Desse modo, constatou-se que, no Brasil, preços mais competitivos obtêm melhores resultados para o crescimento da demanda por gás natural do que aumentos da renda. / The purpose of the present study is to estimate the elasticity, mainly in terms of price and income, of the demand for gas natural in the Brazilian industrial sector. The industry represents around two-thirds of the natural gas consumption in the country, highlighting strategic importance in creating energy policy related to natural gas. This paper also presents the evolution in international trade of natural gas and the perspectives of increased in the use of this energy source in Brazil and worldwide. Some challenges still lay ahead for effective intensification of the gas industry in the country, such as: the increase of investments in infrastructure for production, transport and distribution; the development to the access to major hydrocarbon reserves; the improvements to deal with uncertainties regarding the evolution of demand. Econometric tools are used to estimate price and income elasticity for the Brazilian industrial sector, in other words, to investigate how the natural gas demand reacts to an increase / decrease in the price of gas and in the available income. The industrial GDP is used as a proxy for income. After determining that the series under study were non-stationary, the co-integration approach was chosen and Vector Error Correction Model (VEC Model) was applied. The obtained results show that the price elasticity in the industrial sector in Brazil is significantly higher than income elasticity.
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Elasticidade de substituição: contribuição à análise de competitividade da indústria brasileira de celulose. / Elasticity of substitution: a contribution to the competitivity analysis of the Brazilian pulp industry.Giácoma Frasson Manhães 07 April 2011 (has links)
O setor brasileiro de celulose é um importante pilar da economia nacional. Só em 2010 a exportação de celulose trouxe para o País US$ 4,7 bilhões. Dada a sua importância, este setor já foi alvo de vários estudos de competitividade. No entanto, a mudança no cenário concorrencial global, marcada pela entrada de novos agentes, requer uma avaliação da posição competitiva do Brasil frente aos concorrentes emergentes. Neste contexto, este trabalho teve como objetivo identificar os novos players, descrever a dinâmica concorrencial nos principais mercados, propor ferramentas adequadas para avaliar os resultados dos países exportadores de celulose de fibra curta, e explicar as razões de liderança entre os países exportadores. A fim de mensurar os resultados dos países fornecedores, foi empregada uma função de subcusto translog restrita para obtenção da elasticidade de substituição entre as polpas de fibra curta dos principais países exportadores. Para essa análise foram considerados, separadamente, os mercados americano e chinês. Os resultados obtidos foram analisados levando-se em conta aspectos técnicos da polpas de fibra curta, com foco na morfologia das fibras, e também o histórico de formação dos setores de celulose no Brasil, na Indonésia (fornecedor emergente, principal fornecedor de celulose de fibra curta para a China) e no Canadá (fornecedor tradicional de celulose, principal concorrente do Brasil nos Estados Unidos). Foram também avaliadas as barreiras de mercado à polpa indonésia a partir do testemunho de funcionários e dirigentes de fábricas de papel na América do Norte, Europa e Ásia. As observações feitas sobre a organização setorial e tecnológica dos concorrentes foram comparadas aos modelos correntes de catch up tecnológico a fim de se identificar comportamentos que contribuam para a extensão da teoria nesta área. Os resultados do trabalho indicam que a competitividade brasileira no setor de celulose se apoia na produtividade florestal, resultado da acumulação de competências tecnológicas relacionadas ao eucalipto. Isso garante a competitividade brasileira frente aos concorrentes tradicionais. Frente à polpa indonésia, que vem acumulando competências tecnológicas relacionadas à acácia, a polpa brasileira é competitiva hoje. A manutenção da competitividade da polpa brasileira frente à indonésia no futuro dependerá da intensidade de investimentos em inovação feitos por ambos os países. / Pulp industry is a mainstay of Brazilian economy. In 2010, Brazilian pulp exports totaled US$ 4.7 billion. Given its importance, this industry has been the focus of several studies on competitiveness. However, the change in the competitive global scenario, marked by the entry of new players, requires an assessment of Brazil\'s competitive position towards emerging competitors. In this context, this work aimed to identify new players, to describe the dynamics of competition in key markets, to propose appropriate tools to assess the performance of hardwood pulp exporting countries, and explain the reasons for leadership among the exporting countries. In order to measure the supplier countries results, a restricted translog subcost function was applied to obtain the elasticity of substitution between hardwood pulp from the main exporters. This analysis was performed for both the U.S. and Chinese markets. Results were evaluated considering technical features of hardwood pulp, especially fiber morphology, and also a historic appraisal of pulp industry establishment in Brazil, Indonesia (emerging supplier, main hardwood pulp supplier to China) and in Canada (traditional pulp supplier, Brazil\'s main competitor in the U.S.). Market barriers to the entry of Indonesian pulp were also assessed based on the personal testimony of employees and executives of paper mills in North America, Europe and Asia. Observations on the competitors industry and technology setup were compared to current models of technological catch up in order to identify behaviors or patterns that contribute to the extension of the theory in this area. The results of this study indicate that the competitiveness of the Brazilian pulp industry is based on forest productivity, which result from the accumulation of technological capabilities related to eucalyptus. This ensures Brazilian competitiveness against traditional competitors. Compared to the Indonesian pulp industry, which has been accumulating technological capabilities related to acacia, the Brazilian pulp is currently competitive. Maintaining the competitiveness of Brazilian pulp against the Indonesian in the future will depend on the intensity of innovation investments made by both countries.
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Elasticidades-preço e renda da demanda domiciliar de eletricidade: estimação econométrica com dados da POF 2008/2009Dias, Tuanne Ferreira 24 April 2015 (has links)
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Previous issue date: 2015-04-24 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O presente estudo tem como objetivo obter estimativas de elasticidades-preço, renda e relativas a outras variáveis para a demanda domiciliar de eletricidade segundo 20 grupos da população brasileira em 2008/2009. Os grupos são definidos segundo classes socioeconômicas e regiões macroeconômicas. Tal objetivo é motivado pelo fato de haver poucos estudos na literatura para a demanda domiciliar de eletricidade usando microdados de forma tão pouco desagregada. Para tanto, são usados microdados domiciliares da POF de 2008/2009 do IBGE. A POF 2002/2003 também é usada com o objetivo de comparação entre os dados na análise descritiva, mas não de estimação. Sendo a POF uma amostra de dados complexos, para obter resultados coerentes, considera-se o plano amostral nas estimações e também os pesos de expansão, o que leva ao uso de mínimos quadrados ponderados. Os resultados sugerem que as regiões mais sensíveis ao aumento do preço da energia são Centro-Oeste e Sul e as menos sensíveis Norte e Nordeste, ou seja, o consumo para essas últimas regiões pouco se alterariam com o aumento do preço. Já um aumento na renda domiciliar, as regiões Norte, Nordeste e Sudeste aumentariam mais o consumo de energia elétrica do que as regiões Centro-Oeste e Sul. / This study develops estimates of price and income elasticities, and with regard to other variables, for household electricity demand across 20 groups of the Brazilian population in 2008/2009. The groups are set according to socioeconomic classes and macroeconomic regions. The motivation is the fact that there are few studies in the literature for household electricity demand using microdata so as little broken. Thus, we used household microdata from IBGE’s survey of family budgets POF 2008/2009. The POF 2002/2003 are also used for comparison purposes within the descriptive data analysis, but are not used for estimation. As the POF a complex data survey, in order to obtain consistent results the sampling plan is considered in the estimates including the expansion weights, which led to the use of weighted least squares. The results suggest that regions which are most sensitive to rising energy prices are the Midwest and South, while the North and Northeast are less sensitive, ie the consumption for the latter regions would change little with the price increase. Yet an increase in household income, the North, Northeast and Southeast further increase the power consumption than the Midwest and South.
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<strong>Rock Anisotropy and Nonlinear Elasticity: Implications for Crustal Stress Measurements </strong>Wenjing Wang (16379094) 15 June 2023 (has links)
<p>Crustal stress measurements play a crucial role in understanding how the subsurface deforms. As one of the most popular methods for stress characterization in deep wellbores, borehole breakout analysis examines the shape of drilling-induced compressive failures to determine stress directions and magnitudes, assuming that the rock formation is both isotropic and linearly elastic. To ensure accurate stress interpretations, the dissertation investigates the validity of underlying presumptions from two perspectives: (1) the effect of rock anisotropy (i.e., elastic anisotropy, and strength anisotropy) on wellbore failure patterns; and (2) the characterization of rock nonlinear elastic mechanical behaviors. </p>
<p>The developed computer program, <em><strong>EASAfail</strong></em>, has broad applicability in calculating wellbore failure patterns for a wide range of scenarios. It takes into account factors such as elastic stiffness matrices of the rock, stress tensors in the surrounding environment, and the presence of weak planes. The program's generality allows it to handle various rock types with different degrees of symmetry in their elastic properties, as well as weak planes that are weaker than the intact rock matrix. By analyzing these factors, the program reveals that the patterns of wellbore failure in elastic and strength anisotropic rock formations are highly influenced by the sliding of weak planes. Complications from two modes of borehole failure, either in the intact rock matrix or in the weak planes, can cause the breakout azimuth to deviate from the direction of the minimum horizontal stress. </p>
<p>In addition to hypothetical scenarios generated from numerical models, a case study from the field is presented to underscore the impact of foliations on the anomalous rotations of breakout azimuths. The wellbore was located in Northeastern Alberta, Canada, transecting both the sedimentary column and crystalline basement. Breakout rotations identified from caliper and image logs were highly likely caused by the slippage along foliations, supported by the close correlation between breakout azimuths and dip directions of foliations as well as polarization directions analyzed from dipole sonic logs. Stress magnitudes constrained from Monte Carlo simulations further reveal a lower stress field when rock anisotropy is taken into account, compared to what is inferred conventionally. </p>
<p>The characterization of rock nonlinear elasticity involves the utilization of the third-order elastic (TOE) model. To measure the TOE moduli in a static manner, test-specific protocols were proposed based on the nonlinear stress-strain behaviors of the rock. By arranging the stress-strain responses obtained from hydrostatic, uniaxial, and triaxial compressive tests into a linear system of equations, it becomes possible to invert the equations for the TOE moduli. These analytical equations were validated through calculations from finite element models. </p>
<p>By employing the established protocols, the TOE moduli were derived for four different rock types with varying pore structures when subjected to hydrostatic and uniaxial compressions. The TOE model successfully captured the nonlinear stress-strain responses exhibited by Indiana limestone, Vif-type Fontainebleau sandstone, and Snake River Plain basalt. However, it was found to be inadequate for Franc-type Fontainebleau sandstone, which displayed noticeable hysteresis and experienced significant strains. Future geomechanical applications will undoubtedly gain advantages from utilizing the inverted TOE moduli obtained through static measurements, as they allow for the examination of the impacts of nonlinear elasticity in rocks. </p>
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Experimentální stanovení faktorů ovlivňujících statický modul pružnosti betonu s využitím nedestruktivních zkušebních metod / Experimental determination of factors affecting the static modulus of elasticity of concrete using non-destructive testing methodsKocáb, Dalibor Unknown Date (has links)
The Ph.D. thesis deals with one of the most important characteristics of hardened concrete; i.e. the modulus of elasticity. The thesis aims to describe and evaluate the important factors that affect the final value of concrete modulus of elasticity, especially those that can be influenced during construction. Another aim is to find ways to determine the static modulus of elasticity of concrete by non-destructive means (primarily ultrasonic pulse method, resonance method and use of electronic rebound hammers), thus to determine the possibility of creating calibration curve for NDT determination of the modulus of elasticity.
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PROHIBICE DROG V PODMÍNKÁCH VZÁJEMNÉ SUBSTITUCE NÁVYKOVÝCH LÁTEK V ČESKÉ REPUBLICE / Prohibition of drugs in condition of their mutual substitution with other addictive substances in the Czech RepublicVilimovský, Petr January 2010 (has links)
This thesis analyzes regulation, prescription and prohibition of drugs in condition of their mutual substitution with other addictive substances in the Czech Republic; thesis investigates prices' and cross-prices' elasticities of substances and their markets. Comparison is made between regulated legal markets of alcoholic beverages and cigarettes, non-prohibitively regulated markets of pharmaceuticals and prohibited markets of illegal drugs. The thesis concludes that the demand for drugs is not price elastic. The demand for drugs is price inelastic but not perfectly price inelastic, as can be deduced based on the concept of A Theory of Rational Addiction developed by Gary S. Becker. The price of drugs, therefore, to some extent affects consumption. This opens the room to influence demand through pricing mechanism. The thesis also verifies The Theory of Economic Regulation developed by George J. Stigler and confirms that due to some substitution relationships between addictive substances it is possible speculate about the interests of producers of alcoholic beverages, cigarettes and pharmaceuticals for prohibition of drugs. Interests of producers of alcoholic beverages and cigarettes confirm their mutually complementary linkages.
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所得彈性、價格彈性與貸款成數對中國大陸房地產市場影響之探討 / The effects of income elasticity, price elasticity, and the percentage of loans to mainland China's real estate market周紹軒, Chou, Shao Hsuan Unknown Date (has links)
本研究對中國大陸房地產市場設立需求及供給函數,並使用中國大陸2001 到2009 年的省級資料進行研究分析,以探討中國大陸房地產市場的所得彈性、價格彈性與貸款成數對中國大陸房地產市場供給與需求的影響。
經由實證估計出來的所得彈性值域為1.77 ~ 3.00,價格彈性值域為0.08 ~ -0.80。相較於過往的文獻與研究,估計到的彈性較高,顯現出即便中國大陸房價持續飆漲,民眾仍肯購置房產,且房價飆漲對於房地產市場的需求量影響有限,乃因民眾對於未來的經濟情勢持樂觀的態度。
而貸款成數方面,在貸放資金大增的環境下,對於中國大陸的房地產需求及供給市場大抵而言有顯著影響,而貸款成數的增加也使得房地產需求及供給量跟隨增加。 / The research constructed the demand and supply function for the market of China's real estate, and used the provincial data in China from 2001 to 2009 to analysis. Based on the information, we discussed the income elasticity and the price elasticity, and furthermore the impacts of the percentage of loans on the China's real estate market.
According to the empirical estimate, the range of income elasticity was from 1.77 to 3.00, and for the price elasticity, it was from 0.08 to -0.80. Compare with those previous studies, the higher level of elasticity represented that although the real estate price continued soaring in China, people were still willing to purchase. Moreover, the soaring price had a limited influence in the demand of real estate market, and the main reason was that people were all optimistic about the future.
To the percentage of loans, in this environment of the sharp increase in money lending, we found that it affect the demand and the supply market of real estate significantly, and with the relaxation of credit control, it led the demand and the supply of real estate to increase.
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Mixed Velocity-Displacement Formulation for Modeling of Complex Behavior of PolymerPham, Vu Thu 17 February 2012 (has links) (PDF)
This work concerns the simulation of viscoelastic behavior of polymer at different states. Viscoelastic modeling of polymer was performed from the solid state to the liquid state via a multiphase approach which is largely used to deal with the fluid structure interaction. To ensure the appreciation of the FSI, viscoelasticity is considered in two parts: an elastic one and viscous other where the main idea is to use a mixed formulation in three fields (u, v, p) (displacement, velocity, pressure), with u and v, represented the primary variables of a strain and a strain rate formulation. We are led to the Navier-Stokes compressible problem with extra-stress, which is solved by using the Mixed Finite Element. The present work contributes some stabilization elements to the numerical simulation of multiphase problem by the monolithic approach.Comparison between the literature and experiments was performed through the validation of an elastic case and the viscoelastic Kelvin-Voigt model in the context of Lagrangian framework as well as Eulerian framework. The extension of the methodology to a visco-hyper-elastic is given through the modeling and validation on material point on the finite elements library CimLib®. Finally, a stabilization scheme of the EVSS type is adopted for viscoelastic Kelvin-Voigt model, hyper-elastic Neo-Hookean model, and also visco-hyper-elastic model which proposed an open door in computational modeling, not only with viscoelasticity but also complex dynamic application.
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