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Showing 1 to 20 of 44 for “"Ritz-Method"”.
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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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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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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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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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Free vibration and stability of complete orthotropic circular toroidal shells
… shells using the differential quadrature method. Numerical results are determined using the method for shells with small bend to cross-section radius ratios, and compared with finite element results. Thirdly, theory is developed using the Rayleigh-Ritz method for the free vibration …
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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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An integral equation approach to vibrating plates
… modes are especially important. Many approximate methods have been devised to determine these natural frequencies. In this dissertation a method of frequency determination is suggested through an integral equation approach. The plate vibration problem is formulated as a problem in the solution of …
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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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Vibrações livres de viga de seção transversal variável
… heigh varying according to a polynbmial law. Ritz method is used for the determinátion of the natural frequencies, dueto its rapid convergence. The method of treatment of the problem, permits a determination of any of the natural frequencies using automatic programming because it does not …
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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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ΕΦΑΡΜΟΓΗ ΑΜΕΣΩΝ ΜΕΘΟΔΩΝ ΤΗΣ ΣΥΝΑΡΤΗΣΙΑΚΗΣ ΑΝΑΛΥΣΕΩΣ ΣΤΟΝ ΥΠΟΛΟΓΙΣΜΟ ΑΝΤΙΣΤΑΣΕΩΝ, ΑΥΤΕΠΑΓΩΓΩΝ ΚΑΙ ΧΩΡΗΤΙΚΟΤΗΤΩΝ
… DEALT WITH THE APPLICATION OF DIRECT VARIATIONAL METHODS (E.G. RAYLEIGH-RITZ METHOD, GALERKIN METHOD, KANTOROVICH METHOD) FOR THE CALCULATION OF RESISTANCE, INDUCTANCE AND CAPACITANCE. THE ESTIMATION OF INTERNAL INDUCTANCE OF HIGHLY PERMEABLE CONDUCTORS (M>>M) WITH VAROUS CROSS-SECTIONS IS ONE OF …
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Modal Analysis of Axisymmetric Structures using Zernike Polynomials and Machine Learning
… thesis focuses on advancing vibration analysis 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 …
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Structural acoustic analysis of shape memory alloy hybrid composite panels
… materials. This study utilizes the Rayleigh-Ritz method and finite panel acoustic radiation theory to investigate the use of SMA hybrid composite materials for adaptive structural acoustic control by active structural tuning. Analytical models are formulated considering classical laminated …
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Random vibrations of mistuned periodic structures
… have been designed to withstand. The Rayleigh-Ritz method, as employed earlier, for dynamic analysis for two-span beams could predict only the lower modes of vibration at prohibitive computational expense. A semi-analytical method which predicts even the higher modes at significantly reduced …
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Buckling and postbuckling behavior of prolate spheroidal shells under uniform external pressure
The Rayleigh-Ritz method is used to determine both the buckling and postbuckling behavior of completely, enclosed prolate spheroidal shells under uniform external pressure. It is assumed that the shells are isotropic and elastic, and have a uniformly thin wall. It is further assumed that the …
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Analysis of Pressurized Arch-Shells
… A numerical investigation based on the Rayleigh-Ritz method is utilized to determine the behavior of arch-shells under various types of loading. The types of loading include a uniformly distributed vertical load representing snow, a wind load, and a horizontal side load distributed along the arc …
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Macro Fiber Composite Actuated Unmanned Air Vehicles: Design, Development, and Testing
… fiberglass unimorph was modeled by the Rayleigh-Ritz method and quantified by experimentation. Wind tunnel tests were performed to compare conventional trailing edge control surface effectiveness to an MFC actuated wing section. The continuous surface of the MFC actuated composite airfoil …
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Vibration of a nonlinear shear deformable beam by numerical simulation
… harmonic excitation is investigated by the method of numerical simulation. Rotatory and axial inertia are included in the model. The beam is simply supported with supports a fixed distance apart. The nonlinear partial differential equations of motion are discretized in space by the …
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Vibration and Buckling Analysis of Unitized Structure Using Meshfree Method and Kriging Model
The Element Free Galerkin (EFG) method, which is based on the Moving Least Squares (MLS) approximation, is developed here for vibration, buckling and static analysis of homogenous and FGM plate with curvilinear stiffeners. Numerical results for different stiffeners configurations and boundary …
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