http://belgelik.isikun.edu.tr/xmlui/handleiubelgelik/2389 JAEM 2011, Vol 1, No 2 koleksiyonunu içerir. 2026-04-09T07:48:58Z http://belgelik.isikun.edu.tr/xmlui/handleiubelgelik/2434 Integrating analytical aeroelastic instability analysis into design optimization of aircraft wing structures Nikbay, Melike; Acar, Pınar Two analytical flutter solution approaches have been developed to optimize two and three dimensional aircraft wing structures with design criteria based on aeroelastic instabilities. The first approach uses open loop structural dynamics and stability analysis for a two dimensional wing model in order to obtain the critical speeds of flutter, divergence and control reversal for optimization process. The second approach involves a flutter solution for three dimensional wing structures by using assumed mode technique and is applied to aeroelastic optimization based on flutter criterion efficiently. This flutter solution employs energy equations and Theodorsen function for aerodynamic load calculation and is fully-parametric in terms of design variables which are taper ratio, sweep angle, elasticity and shear modulus. Since bending and torsional natural frequencies are required for flutter solution, a free vibration analysis of aircraft wing is developed analytically as well. The analytical results obtained for flutter solution of AGARD 445.6 wing model for Mach number of 0.9011 are found to be compliant with the experimental results from literature. Next, the three dimensional flutter code is coupled with optimization framework to perform flutter based optimization of AGARD 445.6 to maximize the flutter speed. 2011-09-01T00:00:00Z http://belgelik.isikun.edu.tr/xmlui/handleiubelgelik/2433 Asymptotic results for an inventory model of type (s, S) with a generalized beta interference of chance Khaniyev, Tahir; Aksop, Cihan In this study, asymptotic expansion for ergodic distribution of an inventory control model of type (s, S) with generalized beta interference of chance is obtained, when S ? s ? ?. Moreover, weak convergence theorem is proved for ergodic distribution. Finally, the accuracy of the asymptotic expansion is examined with Monte Carlo simulation method. 2011-10-19T00:00:00Z http://belgelik.isikun.edu.tr/xmlui/handleiubelgelik/2432 Distributional derivatives on a regular open surface with physical applications Polat, Burak The spatial derivatives of Schwartz-Sobolev distributions which display singularities of arbitrary order on an arbitrary regular open surface are investigated. The contributions of the present investigation to literature are i) an approach alternative to the derivation of the distributional derivatives of multilayers by Estrada and Kanwal; ii) an extension of the available results for closed surfaces to open surfaces featuring boundary distributions of arbitrary order. The end results are applied in the distributional investigation of Maxwell equations in presence of single and double layer sources located on a regular open surface. 2011-05-03T00:00:00Z http://belgelik.isikun.edu.tr/xmlui/handleiubelgelik/2431 Energy preserving methods for volterra lattice equation Karasözen, Bülent; Erdem, Özge We investigate linear energy preserving methods for the Volterra lattice equation as non-canonical Hamiltonian system. The averaged vector field method was applied to the Volterra lattice equation in bi-Hamiltonian form with quadratic and cubic Poisson brackets. Numerical results confirm the excellent long time preservation of the Hamiltonians and the polynomial integrals. 2011-09-11T00:00:00Z