The corner point singularity of surface cracks by finite element method (FEM) has become a numerical concern decades ago. The literature showed that the stress intensity factors (SIFs) at the corner points were often excluded. Further, most SIFs were reported for larger ratios of the crack depth over cylinder diameter. This paper presents the SIFs (Modes I, II and III) of a semi-elliptical surface crack at a solid round bar under torsion. The tetrahedral and hexahedral elements were used in the finite element modelling. The effects of the loading mode and the crack aspect ratio on the corner point singularity were discussed. The tetrahedral meshing was generally observed to be more suitable for modelling relatively small surface cracks, particularly in respect to the corner point singularity. For all loading modes, the SIFs away from the corner points of using the tetrahedral meshing were found to have fairly good agreement with those by dual boundary element method (DBEM).

The forming steps by permanent deformation controlled by the tools generate a distribution of stresses inside the material which directly depends on the work hardening properties of the latter. The change in boundary conditions following the removal of the tools imposes the material to redistribute the stresses in the sections in a manner compatible with the new boundary conditions. This new distribution necessarily operates by local elastic deformations that result globally in a general change of shape called springback. This geometrical deviation can be minimized by the meticulous focus of the tools, but it cannot generally be completely annihilated due to the influence of several parameters. For this reason, the study of the influence of the different technological factors and physico-metallurgical parameters on the springback for the different metals is very important to design and properly realize forming tools. The main objective of this work is to find solutions to problems encountered in sheet metal forming such as the problem of springback. Our work has two essential purposes: the first is summarized in an experimental study based on theoretical analyses. To this end, much effort is made to add a new design of parts for a U-type stretch-bending device and adapt it to a tensile testing machine. This design has the advantage of modifying and assembling all parameters affecting springback at the same time and also of carrying out several forming processes on the same device. The second goal is the experimental and numerical prediction of springback, and the study of the effect of various stretch-bending process parameters such as punch velocity, the orientation of the sheet (anisotropy), hold time and punch-die clearance on springback behavior under heat treatment of aluminum alloy sheets with three different rolling directions (0°,45°,90°). A finite element (FE) model of stretch-bending has been established by utilizing ABAQUS/CAE software. From this analysis, it can be concluded that the springback is affected by the anisotropy of the sheet and the heat treatment in the stretch-bending process. The obtained experimental results were compared with the numerical simulations found in good agreement.

The current study links the information contents of the three main financial statements in a balanced panel data model to empirically examine the effect of cash flows per share and capital structure on shareholder value. The results of the study are based on a sample of 270 firm-year observations from the Jordanian commercial banks and insurance companies that listed on Amman Stock Exchange (ASE) from 2011 to 2019. Based on the Fixed Effect Model (FEM) with Driscoll-Kraay standard errors, the empirical results show that cash flows from operating activities per share had a positive and significant relationship with shareholder value, whereas both the cash flows from investing and financing activities per share had negative but insignificant relationship with shareholders’ value. Results also show that capital structure had a negative but insignificant relationship with shareholder value. Finally, the results indicate that dividend per share had a positive and significant relationship with shareholder value. Accordingly, decision-makers should direct cash to efficient investment projects in order for cash outflows from investing activities to create value to shareholders and to generate positive cash flows from financing activities. Similarly, an appropriate capital structure should be selected to create value for shareholders.

In this study, a 3D finite element model of an intact mandible was used for the simulation of the movement of the lower jaw and analysis of the effects of TemporoMandibular Joint (TMJ) prosthesis replacement on the jaw movement. Seven bundles of muscle fibers were inserted in their appropriate positions following anatomical data. Digastric, geniohyoid and lateral pterygoid muscles were considered for opening the mouth while medial pterygoid, superficial masseter, deep masseter and temporalis muscles were used for closing the mouth. Then, the TMJ was replaced by two different types of TMJ prostheses in the same way as in a surgery operation. One of the prostheses was designed based on anatomical shape of the ramus and condyle of the mandible while the other one was taken similar to the commercial TMJ prostheses. Eventually, all three models underwent an opening jaw simulation and produced an identical range of motion while were mismatched in other parameters. The results show that since the anatomical TMJ prosthesis resembles the shape and structure of an intact mandible; therefore, it is more capable of simulating the motion of mandible compared to the commercial TMJ prosthesis. Furthermore, better contact between the anatomical TMJ prosthesis and the mandible leads to lower stress distribution in comparison with the commercial TMJ implant. Finally, as the amount of muscle forces and strain in anatomical TMJ prosthesis replacement are less than the commercial one, the patient needs to make less effort to move the mandible and open the mouth.

In the present world stiffeners are widely used to fulfill the requirement of high stiffness. Stiffened plates are used in most of the mechanical structures. In this paper free vibration analysis of eccentric and concentric stiffened isotropic plate with central stiffener and double stiffener has been studied and effect of various parameters such as boundary conditions, aspect ratio on non-dimensional frequency parameter of plate are investigated. Comparison of non-dimensional frequency parameter for eccentric and concentric isotropic stiffened plate with effect of number of stiffener at different mode shapes, aspect ratios and boundary conditions is studied using ANSYS parametric design language (APDL) code. A ten nodded element (SOLID 187) from ANSYS element library is used for the discretization of proposed stiffened isotropic plate. Convergence study of developed model with respect to the number of modes has been done and results are compared from the related available published literature. Non dimensional frequencies are higher for fully clamped boundary condition for eccentric and concentric stiffened isotropic plate in comparison to other boundary condition. It is also seen that non dimensional frequencies are increases in a moderate value for eccentric and concentric isotopic plate with double stiffener in comparison to the central stiffener.

Cutouts are commonly used as access port for mechanical and electrical structures. Most of the structures generally work under severe dynamic loading and different constrained conditions during their service life. This may lead to vibration of the structure. Therefore, it is necessary to predict the vibration responses of laminated composite plates with cutouts precisely with less computational cost and good accuracy of these complex structures. A suitable finite element model is proposed and developed based on first order shear deformation theory using ANSYS parametric design language (APDL) code. The model has been discretized using an appropriate eight nodded element (SHELL 281) from the ANSYS element library. The free vibrations are computed using Block-Lanczos algorithm. The convergence study has been done of the developed model and compared with those available published literature. Effects of different geometric parameters (aspect ratio, thickness ratio, boundary conditions, number of layers, angle of lamina geometry of cutout, cutout side to plate side ratio and distance between cutouts) and material properties on the free vibration responses are discussed in detail. The frequency increases with increase in the number of layers, modulus ratio of plate and angle of lamina. The frequency decreases with increase in aspect ratio, thickness ratio, size of cutout and distance between cutouts. The boundary conditions of the plate play an important role in the free vibrations of the plate with cutouts. The Non-dimensional frequencies are higher for fully clamped boundary condition in comparison to other boundary conditions.

This piece of work aims at the modeling and using the finite element method approach (FEM) to analyze the fatigue behavior of bolted beam to column end-plate connection in the structural steel framework subjected to static loading. A detailed three dimensional (3D) simulation model of the bolted beam to column end-plate connection is constructed in PRO-E wildfire and it is analyzed in the ANSYS workbench to obtain its behavior. The bolted end-plate connection is chosen as an important type of beam to column joint. The end-plate connection is chosen for its complexity in the analysis and behavior due to the number of connection components and their inheritable behavior. The solid elements, bonded contact and the bolt pretension are included to obtain the behavior of the structure. The FEA results of the structure with or without bolt pretension are compared with the available literature. At last the fatigue behavior of connections under over tensioning is presented in this work.