o bjectives: headgears are among the effective orthodontic appliances to achieve treatment goals. unilateral molar distal movement is sometimes needed during an orthodontic treat- ment, which can be achieved by an asymmetric headgear. different unilateral headgears have been introduced. the main goal of this study was to analyze the force system of uni- lateral expanded outer bow asymmetric hea...

introduction: the fracture strength of endodontically treated teeth compared to vital ones has long been a source of controversy. it is not clear how root canal therapy affects the stress distribution in teeth. the purpose of this study was to evaluate the changes in stress distribution after root canal therapy in a human maxillary canine by finite element analysis (fem). materials and methods:...

This paper presents a simple method based on strain energy density criterion to study the crack initiation angle by finite element method under biaxial loading condition. The crack surface relative displacement method is used to eliminate the calculation of the stress intensity factors which are normally required. The analysis is performed using higher order four node quadrilateral element. The...

in this paper, a positive definite semi-discrete mixed finite element method was presented for two-dimensional parabolic equations. in the new positive definite systems, the gradient equation and flux equations were separated from their scalar unknown equations.  also, the existence and uniqueness of the semi-discrete mixed finite element solutions were proven. error estimates were also obtaine...

The Layerwise Shell Theory is used to model discretely stiffened laminated composite plates and cylindrical shells for stress, vibration, pre-buckling and post-buckling analyses. The layerwise theory reduces a 3-D problem to a 2-D problem by expanding the 3-D displacement field as a function of a surface-wise 2-D displacement field and a 1-D interpolation polynomial through the shell thickness....

In this paper, the finite element analysis of two-dimensional linear viscoelastic problems is performed using quadrilateral complex Fourier elements and, the results are compared with those obtained by quadrilateral classic Lagrange elements. Complex Fourier shape functions contain a shape parameter which is a constant unknown parameter adopted to enhance approximation’s accuracy. Since the iso...

three dimensioned finite element analysis were conducted on concrete block paving. in order to verify the calculated results, an experimental case study was analyzed. good agreement was observed between the measured and the calculated results. based on the finite element analysis results and available failure models, comprehensive design charts were developed for port and industrial pavement wh...

in this paper the critical strain energy release rate for t300/913 carbon-epoxy laminated composites has been studied using ansys finite element software based on virtual crack closure technique ( vcct ). compact tension ( ct ) specimen has been used for numerical analyses and the geometrical dimensions have been extracted from the existing references. the results obtained from the finite eleme...

analysis of the stresses, displacements, and horizontal strains of the ground subsidence due to underground excavation in rocks can be accomplished by means of a hybridized higher order indirect boundary element/finite difference (be/fd) formulation. a semi-infinite displacement discontinuity field is discretized (numerically) using the cubic displacement discontinuity elements (i.e. each highe...