M. T. Ahmadian

Learn More
A molecular structural mechanics method has been implemented to investigate the vibrational behavior of single-layered graphene sheets. By adopting this approach, mode shapes and natural frequencies are obtained. Vibrational analysis is performed with different chirality and boundary conditions. Numerical results from the atomistic modeling are employed to(More)
BACKGROUND AND AIMS OF THE STUDY Mechanical heart valves (MHV) are widely used to replace dysfunctional and failed heart valves. The bileaflet MHV design is very popular due to its superior hemodynamics. Since their introduction in 1977, the hemodynamics of bileaflet prostheses has been extensively studied. In this study the dynamic behaviour during the(More)
In this paper, homotopy perturbation and modified Lindstedt-Poincare methods are employed for nonlinear free vibrational analysis of simply supported and double-clamped beams subjected to axial loads. Mid-plane stretching effect has also been accounted in the model. Galerkin's decomposition technique is implemented to convert the dimensionless equation of(More)
Needle insertion simulation and planning systems (SPSs) will play an important role in diminishing inappropriate insertions into soft tissues and resultant complications. Difficulties in SPS development are due in large part to the computational requirements of the extensive calculations in finite element (FE) models of tissue. For clinical feasibility, the(More)
In this study, an accurate analytical solution for Duffing equations with cubic and quintic nonlinearities is obtainedusing theHomotopyAnalysisMethod (HAM) andHomotopy Pade technique. Novel and accurate analytical solutions for the frequency and displacement are derived. Comparison between the obtained results andnumerical solutions shows that only the(More)
In this study, free vibration analysis of a cross-ply laminated composite beam (LCB) on Pasternak foundation was investigated. Natural frequencies of beam on Pasternak foundation are computed using finite element method (FEM) on the basis of Timoshenko beam theory. Effect of both shear deformation and rotary inertia are implemented in the modeling of(More)
In this paper, a micromechanical model for connective soft tissues based on the available histological evidences is developed. The proposed model constituents i.e. collagen fibers and ground matrix are considered as hyperelastic materials. The matrix material is assumed to be isotropic Neo-Hookean while the collagen fibers are considered to be transversely(More)
Carbon nanoscroll (CNS) is a graphene sheet rolled into a spiral structure with great potential for different applications in nanotechnology. In this paper, an equivalent open shell model is presented to study the vibration behavior of a CNS with arbitrary boundary conditions. The equivalent parameters used for modeling the carbon nanotubes are implemented(More)