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Yayın 3-D Vibration analysis of microstretch plates(Springer, 2008) İnan, Esin; Kiriş, AhmetIn the present work, rectangular plates with various boundary conditions are Studied, which are modeled by the rnicrostretch theory. Wave propagation problem is investigated and new waves are observed which do not appear in the classical theory of elasticity. Ritz method is used for this investigation. Triplicate Chebyshev series, multiplied by boundary functions, are used as admissible functions and the frequency equations of the micro-stretch plate are obtained by the use of Chebyshev-Ritz method. The additional frequencies due to the microstructure of the plate are observed among the values of the frequencies obtained from the classical theory of elasticity. We observed that these additional frequencies disappear while the all microstretch constants are taken as zero.Yayın Thermo-microstretch elastic bodies and plane waves(IOP PUBLISHING LTD, 2011) İnan, Esin; Kırış, AhmetIn the present work, vibration problems of rectangular plates are considered for the determination of upper bounds to the unknown microstretch material properties. The frequencies are obtained by extending the Ritz method to this case. The analysis shows that some additional frequencies characterizing the microstretch effects appear among the classical frequencies. Furthermore, by the increasing values of the microstretch constants, the additional frequencies disappear and only the classical frequencies remain in the spectrum. Considering this phenomenon, an optimization problem is established for the identification of the upper bounds of microstretch elastic constants. In the second part of the work, thermal effects are considered and several theories are discussed. Finally, propagation of the plane waves is investigated.Yayın Estimation of microstretch elastic moduli by the use of vibrational data(Springer, 2007) Kırış, Ahmet; İnan, EsinIn the present work, a nonlinear wave theory is used for the estimation of the material properties of a "microstretch" medium. For this purpose a thin plate is considered and triplicate Chebyshev polynomial series are used as admissible functions to ensure the satisfaction of geometric boundary conditions of the plate. The Ritz technique is applied to derive the frequency equation of the microstretch plate and an optimization procedure is performed by minimising the least square "distance" between computed natural frequencies from the energy method and measured natural frequencies. To realize the optimization procedure, a genetic algorithm is used to estimate the elastic moduli of microstretch medium.Yayın 3-D Vibration analysis of the rectangular micro damaged plates(Springer, 2008) Kiriş, Ahmet; İnan, EsinIn the present work, damaged plates are modeled by the micro-elongation theory which neglects the micropolar effects in Eringen's microstretch theory. The wave propagation problem is Studied and a new wave which does not appear in the classical theory of elasticity is observed. The Ritz method is extended to the microelongation theory and triplicate Chebyshev series multiplied by a boundary function are used as admissible functions to approximate plate deflection, and the frequency equations of the microelongated plate are obtained by using Chebyshev-Ritz method. The additional frequencies due to the microstructure of the plate are observed among the values of the classical frequencies. We examined the relation between these additional frequencies and the material constants of the microelongated medium and observed that these additional frequencies disappear while the all microelongational constants are taken as zero.Yayın A hollow cylinder problem in microstretch theory(Springer-Verlag, 2011) İnan, Esin; Kırış, AhmetA hollow cylinder micro-damaged tube under pressure problem is discussed. Micro damage is modeled with Eringen's microstretch theory and the displacement and its comparison with classical result are given.
