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Showing 1 to 20 of 242 for “"Estabilidade"”.
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Análise de estabilidade em dinâmica industrial
The main objective of this work is to give a contribution to the study and analysis of the stability of systems described by models for "Industrial Dynamics”. To this end, the models are placed under a mathematical formulation suitable for the application of known results about stability; …
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Estabilidade local de painéis cilíndricos enrijecidos
Results from primary and secondary bifurcation loads and also results from a non-linear analysis of elastic local stability of stringer stiffened cylindrical shells under axial compression are presented. The effects due to stiffeners spacing and slenderness as well as modal interaction and inicial …
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Vibrações e estabilidade paramétrica de cascas axissimétricas
The general problem of Dynamics of Elastic Bodies is presented, and the problems of dynamic response and stability of rotating axisyrnmetric shells, under a non-rotating load, are studied. Using a Fourier series expansion for the circunferential variable it is shown that this load generates a …
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Estabilidade das grelhas de convés de navios
Based on the study of ultima loads for the ship hull girder, we establish the need of determining instability loads of deck grillages. After a review on existing methods anc. accurate theory, including torsional and shear effects, is developpedfor the response of a one dimensional structure element …
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Análise da estabilidade intacta de navios de apoio offshore sob perspectiva da segunda geração de critérios de estabilidade da IMO
One of the main topics of study related to the safety, comfort or operability of a floating structure is its intact stability. Currently, the rules in use are known as the first generation of stability criteria of the International Maritime Organization (IMO), which are mainly based on static …
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Estabilidade de Hipersuperfícies com Curvatura Média Hr+ Constante
Definimos a noção de r-estabilidade sobre hipersuperfícies fechadas com curvatura de ordem superior Hr+1 constante em um forma espacial Riemanniana. Com a hipótese de que uma tal hipersuperfície Mn esta contida ou em um hemisfério aberto de uma esfera Euclidiana ou no espaço Hiperbólico, …
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Avaliação da estabilidade física de emulsões contendo limoneno
In recent years the Ministry of Health has provided therapeutic and preventive options to users of SUS , among them the use of medicinal plants and her bal medicines. Natural vegetable oils have many advantages for therapeutic use , such as low toxicity , biodegradability , and are renewable for …
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Estudo da estabilidade de circuitos RC via otimização
Study of non-linear RC network stability. An RC network is considered assymptotically stable when the capacitar charges converge to equilibrium charges. The study is developed from the analysis of the behavior of resistive networks. It is assumed that all resistors have increasing characteristics …
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Sistemas de pagamentos e estabilidade financeira : o caso brasileiro
A ocorrência de alguns eventos na história recente mostrou ao mundo os riscos envolvidos nos processos de liquidação de transações financeiras e o potencial de que eventuais distúrbios nestes processos contaminem e desestabilizem os mercados financeiros e as economias em geral. Por serem utilizados …
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Adaptabilidade e estabilidade de produtividade em progênies de soja
… a mudança dos padrões de adaptabilidade e estabilidade no processo seletivo e propor um novo método de recomendação de genótipos baseado nas predições BLUP. Os dados de produtividade utilizados neste trabalho são oriundos de linhagens experimentais do Programa de Melhoramento da Qualidade …
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Análise modal assintótica da estabilidade de estruturas reticuladas espaciais
This work presents a solution, by the Finite Element Method, for non-linear asymptotic analysis of elastic stability for space frames under conservative loads. The general non-linear equilibrium and critical equilibrium equations are obtained through a Lagrangian formulation, by analysing the …
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Resposta dinâmica e estabilidade de tubos com escoamento interno
In this work, a finite element model is developed to analyze: linear and non-linear transient response and free vibrations problems and dynamic stability of pipes conveying fluid. Making use of an updated lagrangian formulation for the principle of virtual work the incremental equations of motion …
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Análise de estabilidade elástica pelo método dos elementos finitos
Study the elastic stability of structures, using the finite elements method. In the first part it is presented an overall view of the stability criteria, and the essential differences among them. Using the criteria of the stationary value of the potential energy we have modified the method of …
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Análise da estabilidade lateral em ambientes fluviais do semiárido paraibano.
In a environmental system the physical elements that compounds the landscape are interrelated as a organized whole, so that its organization is connected to the system stability, however its stability should not be understood as a state which the system remains static, but should be seen as …
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Um modelo matemático para estabilidade elástica de cascas cilíndricas enrijecidas
A mathematical model to investigate non-linear branching equilibrium paths of stringer stiffened cylindrical shells under axial compression is presented. This model is based on a general displacements solution of the dynamic non-linear differential equilibrium equations for an isotropic thin …
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Análise da estabilidade de métodos de integração passo a passo
ln this work the Galerkin's and Newmark's step-by-step integration methods are studied. Using the Equivalence Theorem, due to Lax and Richtmyer, convergence criteria are establishedd to this algorithms. Finally a comparison between these two methods, when applied to a single degree of freedom …
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Extração e estabilidade do corante azul de jenipapo (Genipa americana L.)
… temperatura na produção do corante, e estudar a estabilidade dos pigmentos obtidos por diferentes solventes. Para a obtenção do corante o experimento foi conduzido para três níveis de solvente (água, solução aquosa de etanol 50% e álcool etílico 95%); seis níveis de pH (4,0; 5,0; 6,0; 7,0; 8,0 e …
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Método da forma normal e suas aplicações em oscilações e estabilidade
An analytical-numerical method for the study of nonlinear systems of ordinary differential equations near an equilibrium point, especially 1n the case of a bifurcation. This method is called "Normal Form Method" (NFM) and it is based in the Normal Form Theory and Center Manifold Theory. We derive …
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Estabilidade de taludes de solos residuais de granito e de gnaisse
Part One is concerned with a methodology for the study of granitic-gnaissic residual slopes with an emphasis on its heterogeneities - with respect to stratigraphy, shear strength, permeability, infiltration - wich ultimately govern the potential sliding surfaces. The basic point is the …
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Estabilidade térmica da coercividade e viscosidade magnética no nano compósito FeCo/MnO
Nano estruturas magnéticas têm despertado bastante interesse recentemente devido µas propriedades diferenciadas em relação aos sistemas massivos. O sistema nanocomposito Fe40Co60=MnO produzido por mecano -síntese, e tratado termicamente (400oC) por diferentes tempos, foi o sistema investigado nesta …
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