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Showing 1 to 20 of 108 for “"Ritz"”.
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Reconciliation of a Rayleigh-Ritz beam model with experimental data
In order to perform structural optimization and/or modification on a structure, an analytical model which sufficiently describes the behavior of the structure must be developed. Analytical models can be generated for almost any structure, but such a model will generally not effectively predict the …
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Analysis of a circular arch by the Rayleigh-Ritz method
The Rayleigh-Ritz method is a convenient tool for the analysis of deflections in structures subjected to external forces. Bending moment relations can be developed and reliable values obtained for bending moments. In this thesis the Rayleigh-Ritz method is used for the analysis of a single-span, …
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A utilização de vetores de Lanczos-Ritz na condensação dinâmica de estruturas
… the substructure representation by its Lanczos-Ritz vectors were implemented. A correction in the substructure base of transformation through an iterative process was proposed in order to obtain a correct modal representation of inertia forces.
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Aplicacion del metodo de Ritz a funcionales relajados en mecanica de los solidos
… these functionals. The classical theory of the Ritz Method is developed, but when dealing with convergende of the aproximated solutions and performance of the Ritz coefficients, the theory of operators in Hilbert spaces is introduced; this makes it possible to have the problem in an elegant, …
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Free Vibrations and Static Deformations of Composite Laminates and Sandwich Plates using Ritz Method
In this study, Ritz method has been employed to analyze the following problems: free vibrations of plates with curvilinear stiffeners, the lowest 100 frequencies of thick isotropic plates, free vibrations of thick quadrilateral laminates and free vibrations and static deformations of rectangular …
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Integração direta da resposta em regime permanente pelo Método de Ritz-Wilson com mudança de base
… cycle of the excitation. The superposition of Ritz-Wilson vectors is used for the transient response solution. Basis change approaches are also presented to allow the application of the Ritz-Wilson method in the solution of dynamic response due to generic load cases. The final purpose of this …
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Análise estática não-linear geométrica de estruturas pelo método de superposição modal com base Lanczos-Ritz
The purpose of this work is to present the method of linear buckling mode superposition as a procedure for geometric nonlinear static analysis of slender structures, and to examine, as an alternative to a modal basis, the use of a coordinates transformation constitutes by vectors produced in a …
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Aplicação do método de Ritz extendido na análise de vibrações e estabilidade dinâmica de placas circulares
… transverse vibration. It was used the Ritz method to form a minimizing sequence for the energy functional. Initially a review of the basic principles of the variational calculus is presented. Then, the problem of axisylmmetric, transverse vibrations of a circular plate with torsional …
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Nonlinear free vibration of beams by one-dimensional and elasticity solutions
… free–free beam is studied based on the Ritz method. The equation of motion is derived depending on Hamilton's principle. A validation of the Ritz method formulation has been conducted by comparison with the Euler–Bernoulli beam theory. The impact of three-dimensional beam length has been …
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Global/local analysis of laminated panels with cutouts and cracks
… the first step a global approach, the Rayleigh-Ritz method, is used to calculate the response of the structure. Displacement based Ritz functions for the plate without the cutout are augmented with a perturbation function. which is accurate for uniform thickness isotropic plates only, to account …
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Modal Analysis of Axisymmetric Structures using Zernike Polynomials and Machine Learning
… methods for stiffened circular plates. The Ritz method, utilizing Zernike and Legendre polynomials as trial functions, is implemented to enable free-vibration analysis without the meshing constraints typically associated with traditional finite element methods. This approach allows arbitrary …
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Free vibration and stability of complete orthotropic circular toroidal shells
… Thirdly, theory is developed using the Rayleigh-Ritz method for the free vibration analysis of toroidal shells having large bend to cross-section radius ratios. A parametric study of such shells including orthotropic and ring-stiffened isotropic ones is conducted using the finite element method. …
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Flexural-Torsional Coupled Vibration of Rotating Beams Using Orthogonal Polynomials
… vibration of rotating beams using the Rayleigh-Ritz method with orthogonal polynomials as basis functions is studied. The present work starts from a review of the development and analysis of four basic types of beam theories: the Euler-Bernoulli, Rayleigh, Shear and Timoshenko and goes over to a …
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Συμπεριφορά πλακών συνθέτων υλικών υπό συνθήκες κρούσης χαμηλής ταχύτητας
… δίνει εκτιμήσεις για την ακρίβεια της μεθόδου Ritz με τη χρήση των αποδεκτών συναρτήσεων p-Ritz. Η μέθοδος Ritz επιτρέπει την πλήρη μοντελοποίηση του πολύστρωτου λαμβάνοντας υπόψη και τους καμπτικούς όρους σύζευξης κάτι που μέχρι στιγμής δεν έχει παρουσιαστεί στη βιβλιογραφία. Κατά τη δεύτερη …
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An integral equation approach to vibrating plates
… with results obtained from the Rayleigh-Ritz method. Finally, the fundamental frequency is determined for the circular, stepped cantilever plate and the clamped elliptical plate. For the stepped plate fundamental frequency curves are drawn for various positions and magnitudes of the step. …
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Estudo teórico da estabilidade lateral de hastes submetidas a uma protensão externa
… Criteria of Stability", via the Rayleigh-Ritz Method. An analysis of bifurcation taking into account the non-linear terms, for one of the considered cases is made, as well as a discussion on stability by means of the parameters of the characteristic equation obtained from the eigenvalue …
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Thermal Analysis and Response of Grid-Stiffened Composite Panels
… a linear undeformed prebuckling state. Rayleigh-Ritz Method, which utilizes minimization of the total energy of a structure to determine the buckling loads, is used to govern the buckling analysis of composite laminates forming the panel. Lagrange Multiplier Method is used along with the …
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Finite element analysis of geodesically stiffened cylindrical composite shells using a layerwise theory
… and adapted to circular cylindrical shells. The Ritz variational method is used to develop an analytical approach for studying the buckling of simply supported geodesically stiffened shells with discrete stiffeners. This method utilizes a Lagrange multiplier technique to attach the stiffeners to …
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