the cracked brazilian disc (cbd) specimen is widely used in order to determine mode-i/ii and mixed-mode fracture toughness of a rock medium. in this study, the stress intensity factor (sif) on the crack-tip in this specimen is calculated for various geometrical crack conditions using the extended-finite element method (x-fem). this method is based upon the finite element method (fem). in this m...

the aim of this work is to investigate the variational discretization and mixed finite element methods for optimal control problem governed by semi linear parabolic equations with integral constraint. the state and co-state are approximated by the lowest order raviart-thomas mixed finite element spaces and the control is not discreted. optimal error estimates in l2 are established for the state...

although some piecemeal efforts have been made to investigate the validity and use of the iranian phd exam, no systematic project has been specifically carried out in this regard. the current study, hence, tried to attend to this void. as such, to ensure a balanced focus on test interpretation and test consequence, and to track evidence derived from a mixed–method study on the validity of irani...

in this paper, conjugate heat transfer of magneto hydrodynamic mixed convection of nanofluid about a vertical slender hollow cylinder embedded in a porous medium with high porosity have been numerically studied. the forchheimer’s modification of darcy’s law was used in representing the nanofluid motion inside the porous media. the governing boundary layer equations were transformed to non-dimen...

the paper is concerned with a methodology of optimal design of shells of minimum weight with strength, stability and strain constraints. stress and strain state of the shell is determined by galerkin method in the mixed finite element formulation within the geometrically nonlinear theory. the analysis of the effectiveness of different optimization algorithms to solve the set problem is given. t...

This paper proposes an automatic DJ mixing method that can automate the processes of real world DJs and describes a prototype for a fully automatic DJ mix-like playing system. Our goal is to achieve a fully automatic DJ mixing system that can preserve overall user comfort level during DJ mixing. In this paper, we assume that the difference between the original and adjusted songs is the main cau...

This paper compares six commonly used QT correction models and three available parameter estimation methods using five indices for QTc evaluation based on real and simulated electrocardiograph (ECG) datasets. The results show that the golden section approach always finds the correction factor making QTc interval uncorrelated to heart rate for all six formulas. However, the correction formulas d...

ZnFe2O4 mixed spinel ferrite nanoparticles obtained through a citrate-nitrate combustion method. Ignited products calcined at different temperatures in 600-900ºC range and effect of calcination treatment temperature investigated. Final Products characterized by X-ray Diffraction (XRD), Fourier-Transform Infrared spectroscopy (FTIR), and Field Emission Scanning Electron Microscopy (FESEM). The a...

work engagement literature has been dominated by quantitative research methods. this article aims to study work engagement antecedents using mixed-method sequential explanatory design. this design starts with the collection and analysis of quantitative data followed by the subsequent collection and analysis of qualitative data. the qualitative phase of the study was designed to incorporate the ...