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Showing 1 to 20 of 28 for “"Rayleigh-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 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
… coupled 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 …
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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
… the "Dynamic 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 …
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Thermal Analysis and Response of Grid-Stiffened Composite Panels
… assuming 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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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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Structural acoustic analysis of shape memory alloy hybrid composite panels
… composite 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 …
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Random vibrations of mistuned periodic structures
… 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 …
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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 …
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Macro Fiber Composite Actuated Unmanned Air Vehicles: Design, Development, and Testing
… on 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 …
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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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An investigation of the effects of curvatures on natural vibration characteristics of curved beams and plates
… are mostly investigated through the numerical method. In the numerical model, the curved beam or plate is easily simulated by assembled elements. Although the approximate solution can be obtained, numerical results are inadequate to demonstrate the effect of the curvature on the whole system. …
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Natural frequencies and an atlas of mode shapes for generally-laminated, thick, skew, trapezoidal plates
… as aircraft components, and thus, an accurate method of predicting response is required. Even laminated structures that are considered thin can be significantly affected by transverse shear effects, and as a result, transverse shear should not be neglected. The free vibration response of …
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Three-Dimensional Analysis of Geosynthetic Reinforcement Used in Column-Supported Embankments
… the total and differential settlements. Current methods of analysis for this material are extremely simplified, and do not thoroughly model the behavior of the system. Therefore, a more comprehensive analysis needs to be conducted that will better predict the true effect of the geosynthetic layer …
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Optimization parameters for a membrane polygonal body of revolution with zero meridional stress and its application to parachutes
… that the performance index is optimized. Several methods are utilized to solve for the optimum conditions, and an application of these solutions to a parachute design is shown. The results are presented in parametric form with pressure distributions, structural flexibility, and skirt closure angle …
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A Study of Distributed Active Vibration Absorbers (DAVA)
… of a multi-DAVA system was developed using the Rayleigh-Ritz method coupled to a hierarchical finite element set (p-method). The numerical model was validated and used to optimize DAVA configurations using lightweight treatments (< 10 % the weight of the base plate weight). The optimizations …
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Analysis and Compensation of Imperfection Effects in Piezoelectric Vibratory Gyroscopes
… were studied. Hamilton's principle and the Rayleigh-Ritz method provided an effective approach for modeling the coupled electromechanical dynamics of piezoelectric resonators. This method produced accurate results when applied to an imperfect piezoelectric vibrating cylinder gyroscope. The …
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Global/local analysis of laminated panels with cutouts and cracks
… of a simple and accurate global/local method for calculating the static response of simply-supported, laminated composite panels, with cutouts and cracks. The approach primarily involves two steps. In the first step a global approach, the Rayleigh-Ritz method, is used to calculate the …
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