3D imagination of human's organs has become feasible by digital image processing techniques and algorithms via CT or MRI images in recent years. In this study, a new method for reverse engineering and biomodelling of hard tissues by CATIA cloud points' concept has been considered. Comparing with the current softwares (e.g. BioBuild or Mimics) has shown the new method's easiness of implementing and modelling, final model's high accuracy, easiness of data exchanging with the rapid prototyping systems and reduction of need for having anatomical background for interpreting the CT or MRI images. تفاصيل المقالة

Wide range of planar structures in new technologies has attracted special consideration. In this research vibration behavior of plates with non-linear edges is investigated by means of finite difference (FD) method. For this issue, classical and analytical solutions for plates with linear edges were analyzed and mutual equations, needed for numerical calculation were extracted. By expanding the current equations to the non-linear edged plates (e.g. elliptical plates), natural frequencies of this special structure were analyzed numerically and computer simulation with ANSYS software. According to the un-existence of classical or analytical solution for this special configuration, closeness of numerical analysis and computer simulation confirms the accuracy of selected method in this study. تفاصيل المقالة

Now a days, structures with planar geometry such as Sheet metals, have attracted special consideration among advanced techno logia, and hence investing vibration behavior of sheet metal is of prim important . In particular regarding dynamical investigations, if the natural frequencies get ignored, the resonance phenomena can exert noun computing damages to the structure and systems. In this research for investigating the plates' vibration behavior, finite difference method with error orders of and is implemented. At first, the classical and analytical solutions are reviewed and then relevant equations, needed for numerical analysis, are extracted for those mentioned error orders. Finally the obtained natural frequencies for both modes are compared non-dimensionally. In this research , finite difference method using error order , is being applied for the first time, however the results of various references and simulation with ANSYS software are used to verify the outcome and accuracy of the proposed method. تفاصيل المقالة

Structures with planar geometries and analyzing their vibration behavior have attracted special and deep consideration these days. In this research for investigating the orthotropic plates' vibration behavior, finite difference method with error orders of and are implemented. At first, the classical and analytical solutions are surveyed and then relevant equations, needed for numerical analysis, are extracted for those mentioned error orders. Finally the obtained natural frequencies for both modes are compared non-dimensionally. Also simulation with ANSYS software is performed for validation of the results and confirmation of the proposed method's accuracy. تفاصيل المقالة