1. Introduction: In the present paper, electromechanical FINITE ELEMENT modeling of a smart adaptive composite beam is presented. The model is formulated based on linear electromechanics and electro kinematics assumptions. The proposed model is a three layers piezoelectric composite beam that acts as a transverse actuator. The elastic material of the core is isotropic whereas the outer piezoelectric layers are orthotropic. The accuracy of analytic and numerical models is demonstrated by examining the simulation of the two principles of mechanical and electrical energy conservation in a FINITE ELEMENT program and also comparing its results with the ANSYS numerical model. In the numerical simulation of the FINITE ELEMENT model, there are three mesh including 10, 50, and 100 ELEMENTs. The parametric simulation consists of three mechanical, electrical, and electromechanical static loading sets. By comparing the results of modeling in the FINITE ELEMENT programming and ANSYS, and verifying the principle of electromechanical energy conservation, it can be concluded that the proposed FINITE ELEMENT model is efficient and accurate. . .

Changes of up to 80°C has been reported for oral cavity temperature. This could well effecti on the nature of restorations for example failure of bonding of adhesive restorations. It is advocated that using opaque layer in porcelane to restorations could reduce this problem. This experimental study was designed to evaluate the effect mentioned using FINITElement analysis method.Results showed that cooling has a more destructive effect than warming process restorations with the presence of opaque having a FINITElement analysis effect on restorations.

In recent decades, the use of an efficient and cost-effective method to provide soil stability has been a major challenge for civil engineers. With the increasing urban population, the need for underground spaces increases, and deep excavation is an inevitable affair in civil projects. Deep tunnels and large buildings require deep excavations, which must use some techniques to stabilize it. Soil-nailing (reinforcing soil at the site) due to the fast build, is a good way to provide stability. It can also be described as a top-down construction technique for the improvement of the behavioral properties of the in-situ soil mass. The soil-nailed system is formed by inserting relatively slender reinforcing bars into the slope. Depending upon the project cost, site accessibility, availability of working space, and the soil and groundwater conditions, soil-nails can be inserted into the ground. Soil-nail is generally known as conventional and injectable nails but nails with screw plates or "helical soil-nails" are also important due to the faster build and no need for groutings. Helical soil-nails are a new alternative to the conventional soil nails or tie-backs for stabilization of slopes, excavations, and embankments due to ease of installation, minimal site disturbance, and immediate loading capability. Helical soil-nails are installed by application of torque without a drill hole and derive its capacity from one or more helical plates attached to the nail. The shear strength-displacement behavior at the interface is an important parameter in the design of various geotechnical engineering projects, for example, soil-nails, retaining walls, shallow foundations, pile foundations, etc. In soil-nailing, the behavior of the interface between the soil and nail estimated by the pull-out test. The behavior of interface is governed by numerous factors, such as stress conditions, soil properties, method of installation, and soil-nail interface boundary conditions. The pull-out resistance is measured as the most important factor in the design of the nailing system, by the pull-out test. This study, because of limited learning of helical soil nail, aimed to investigate the pull-out resistance by a 3D FINITE ELEMENT modeling with Abaqus software and compare its results with laboratory data. A review of the literature for the screw soil-nails, as well as a comparison of its performance with conventional soil nails, are discussed and numerical results of a series of pull-out tests on a screw soil-nail are presented. And a review of the overburden pressure and plate number and plate distance effect is followed. The results show that in helical soil-nail pull-out a high overburden pressure effect can be seen. A linear relationship between peak pull-out force and overburden pressure is observed for different methods of calculating the helical soil-nail capacity that it is indicating that it follow the Mohr-Coulomb failure criteria. Rupture surfaces occur at distances farther than the nail surface, and three times the diameter can be considered the optimal distance of the plates. Using fewer plate distances does not increase resistance, also using more plates with fewer distances does not increase resistance. A comparison of modeling and laboratory results indicates that modeling of the pull-out test can model the behavior of helical soil-nail and verify its performance in a field soil slope.

Background and Aim: The movement of molars has been evaluated in many studies to correct Cl II malocclusion by non-compliance appliances but the results are controversial. The aim of this study was to compare the upper first and second molars' movement in cervical headgear (HG) and pendulum appliance (PEND) by FINITE ELEMENT method.Materials & Methods: For modeling process, one of the best dry skulls was CT scanned (l mm slices). Modeling was done according to the mechanical properties of cortical and trabecular bone of maxilla and PDM and teeth and transferred to computer by scanner. ELEMENTing, meshing and loading was done. The magnitude of force for both appliances was 250 gr and line of force for HG was 20 degree above the occlusal plane action and for PEND was along the midlingual surface of upper first molar crown. Tooth movement analysis was performed by the software named Ansys 5.71.Results: The amount of dislocation of the 1st molar cusps tip (mesiobuccal, mesiopalatal, distobuccal, distopalatal) at presence of second molar in bucco-lingual dimension showed distal-in rotation in HG and mesial-in rotation for pendulum. In mesio-distal dimension, the four cusps of 1st molar moved distally in HG and palatal cusps moved more in PEND. In vertical dimension, 1st molar showed extrusion in HG and intrusion in PEND for distal cusps.Conclusion: The presence of second molar had impact on the quality of upper first molar in both appliances and it moved in a distal direction, extruded and buccal drifted in both of them. Therefore, with regard to the cooperation of the patients, pendulum appliance is recommended to correct Cl II malocclusion instead of cervical headgear.

Owing to the significant changes in tyre geometry especially for truck tyres with complex patterns and high thickness at tread area, the effect of heat transfer in circumferential direction on temperature field development during tyre curing should be taken into account. This work is basedon the development of a three dimensional nonlinear FINITE ELEMENT model for simulation of tyre curing process of in mould. The heat conduction equation was solved by the use of a standard Galerkin technique in a Cartesian coordinate system. Transient temperature field was modelled using the implicit-  q method. The Kamal and Sourour empirical cure reaction kinetic equation was also used to calculate the state and rate of cure as a function of time. Based on the developed model, an interactive computer program was written in Visual Basic. This program was used to simulate the curing process of a 12-24 truck tyre in mould. Results of our simulations showed that distributions of both temperature and state of cure in circumferential direction cannot be ignored. The applicability of the model was also verified by comparison between the temperature profiles at two points inside the tyre with experimental data. It has been shown that there is a very good agreement between the model predictions and actual data.

Background: Since three decade ago, the application of the concept of FINITE ELEMENT analysis (EEA) have received a keen interest among dental investigators. In practice the FEA provides detailed stress information regarding to a non-homogenious body such as craniofocal skeletal growth, tooth post ceramo-metal crowns and etc. The aim of this study was the determination of the influence of stress distribution at the cement interface of metal ceramic restoration-dentin. Materials and Methods: An idealized metal-ceramic crown model was developed. The model was divided into very small segments. Various loading conditions was applied to the model. A super sap software was used for analyzing the stress distribution. Results & Conclusion: The results of this study suggest that the higher shear stress was developed in the cervical region by two dimensional methods.

Background and Aim: Considering the importance of the design of framework in the stress distribution and probability of creating initial cracks in connectors region, proper design of framework is considered as a requirement. For this purpose, in order to examine the stress distribution in two designs of straight and curved framework, comparison was made using FEM method.Materials and Methods: Research using a descriptive method of FEM was performed. A laboratory prototype was produced and was scanned in a digital form, using CMM equipment by the laboratory and a super spot from the geometry of the part was created. The super spot was transformed to a 3D solid model by utilizing Catia software. The above model was divided into a high number small ELEMENTs, using Meshing method, by Abaqus software to analyze the FINITE ELEMENTs. Afterwards, by Boundary Condition definition, the part was ready to be analyzed. The mechanical properties of Zirconia was entered into the software in the form of a table. Reviewing stress distribution in the bridge specially with the stress on connectors region was performed. Three vertical loading models for each part were applied in central and distal Fosa and analyzed separately.Results: In this study, the findings were described in the form of Von mises stress in Mpa scale. The stress in the Curved model was more than the Straight model. As a result, the stress distribution is more desirable.Conclusion: According to the results of this study, the straight model showed a more desirable stress distribution compared with the curved model. However, it should be noted that these results were obtained in F.E. environment.