The effect of anchor embedded length and impact load on the mechanical properties of adhesive concrete joint under different dynamic loading rate was studied [1]. Hopkinson pressure bar was used to apply dynamic load to specimens. Specimens with through hole and embedded anchor lengths of 2.5 cm and 5 cm were used in the study. The specimens were hit with strain wave induced using air pressure of 1 and 1.5 bar respectively. The result showed that as the embedded length decrease the maximum load of failure increase also as the pressure increase the specimen tend to absorb most of the wave in the adhesive joint. While as the load wave magnitude decrease the portion of the wave transmits to the concrete part of the specimen causing rupture or cracking of this part increase.

The effect of anchor embedded length and impact load on the mechanical properties of adhesive concrete joint under different dynamic loading rate was studied [1]. Hopkinson pressure bar was used to apply dynamic load to specimens. Specimens with through hole and embedded anchor lengths of 2.5 cm and 5 cm were used in the study. The specimens were hit with strain wave induced using air pressure of 1 and 1.5 bar respectively. The result showed that as the embedded length decrease the maximum load of failure increase also as the pressure increase the specimen tend to absorb most of the wave in the adhesive joint. While as the load wave magnitude decrease the portion of the wave transmits to the concrete part of the specimen causing rupture or cracking of this part increase.

The effect of anchor embedded length and impact load on the mechanical properties of adhesive concrete joint under different dynamic loading rate was studied [1]. Hopkinson pressure bar was used to apply dynamic load to specimens. Specimens with through hole and embedded anchor lengths of 2.5 cm and 5 cm were used in the study. The specimens were hit with strain wave induced using air pressure of 1 and 1.5 bar respectively. The result showed that as the embedded length decrease the maximum load of failure increase also as the pressure increase the specimen tend to absorb most of the wave in the adhesive joint. While as the load wave magnitude decrease the portion of the wave transmits to the concrete part of the specimen causing rupture or cracking of this part increase.

This paper introduces a new technique for deep drawing of elliptic cups through a conical die without blank holder or draw beads. In this technique an elliptical-cup is produced by pushing a circular blank using a flat-headed elliptic punch through a conical die with an elliptic aperture in a single stroke. A 3D parametric finite element (FE) model was built using the commercial FE package ANSYS/APDL. Effects of die and punch geometry including, half-cone angle, die fillet radius, die aperture length and punch fillet radius on limiting drawing ratio (LDR), drawing load and thickness strain of the cup have been investigated. A die with half cone angle of 18° has shown the best drawability for the new technique. Finite element model results showed good agreement with experimental results. A die with an aspect ratio of 2 has been used with punches having aspect ratios ranging from 2 to 2.25. Tensile tests were carried out to obtain the stress-strain behavior for the used material. A total of seven punches were used for forming sheet metal of brass (CuZn33) with initial thicknesses of 1.5, 1.9, 2.4 and 3.2 mm at different clearance ratios (c/t). The effects of blank thickness and clearance ratio on limiting drawing ratio, drawing load and thickness strain were experimentally investigated. An elliptic cup with a limiting drawing ratio (LDR) of 2.26 has been successfully achieved.

This paper introduces a new technique for deep drawing of elliptic cups through a conical die without blank holder or draw beads. In this technique an elliptical-cup is produced by pushing a circular blank using a flat-headed elliptic punch through a conical die with an elliptic aperture in a single stroke. A 3D parametric finite element (FE) model was built using the commercial FE package ANSYS/APDL. Effects of die and punch geometry including, half-cone angle, die fillet radius, die aperture length and punch fillet radius on limiting drawing ratio (LDR), drawing load and thickness strain of the cup have been investigated. A die with half cone angle of 18° has shown the best drawability for the new technique. Finite element model results showed good agreement with experimental results. A die with an aspect ratio of 2 has been used with punches having aspect ratios ranging from 2 to 2.25. Tensile tests were carried out to obtain the stress-strain behavior for the used material. A total of seven punches were used for forming sheet metal of brass (CuZn33) with initial thicknesses of 1.5, 1.9, 2.4 and 3.2 mm at different clearance ratios (c/t). The effects of blank thickness and clearance ratio on limiting drawing ratio, drawing load and thickness strain were experimentally investigated. An elliptic cup with a limiting drawing ratio (LDR) of 2.26 has been successfully achieved.

Fatigue behaviour of rubber is a very important characteristic due to its extensive use in many engineering applications. In most applications, rubber is commonly subjected to fluctuating loads, which often lead to failure due to the nucleation and growth of defects or cracks. Due to their viscoelastic behavior, rubbers have a high damping ability. Very often rubbers are subjected to different frequencies in the service, such as engine mounts. The effect of frequency on the fatigue lifetime needs deep investigations. In present work, the effect of frequency on the styrene butadiene (SBR) and nitrile-butadiene rubber (NBR) with 0,20,30,50 and 70 Phr of carbon black was investigated. It was found that the fatigue lifetime decreased with the increase of the frequency. Increasing carbon black (CB) contents in rubber improved the fatigue resistant and increased of the fatigue lifetime.

Thin-walled square columns are generally used as impact energy absorber in automotive structures due to their ease of fabrication and installation, high energy absorption capacity in terms of progressive plastic deformation and long stroke. However, the main drawback of standard square column is the high initial peak force. An external tapered plunger is proposed to overcome this shortcoming while at the same time, improving the impact performance. Static and dynamic axial crushing were performed by theoretical and finite element analysis to determine the initial peak force (IPF), crush force efficiency (CFE) and plastic specific energy absorption (SEA) of columns with external plunger of various taper angles. The simulations results were validated by experiments. It was found that the external plunger significantly enhanced the column impact performance and the deformation characteristics as well. Comparison with plain square column was carried out and it was found that the concentric plunger reduced the initial peak force and increased the crush force efficiency for both static and dynamic loading conditions.

In this research, slurry erosion-corrosion and slurry-erosion resistances of electroless Ni-P coatings have been investigated. These coatings were applied on AISI 5117 steel discs by electroless deposition process and then they were heat treated at 650 C for 1 h. Slurry erosion-corrosion and slurry-erosion resistances of deposits were measured by the whirling-arm tester. Also, microstructure of deposits before and after heat treatment was evaluated by X-ray diffraction (XRD) analysis. The results showed that the electroless Ni-P plating greatly increased the erosion and erosion-corrosion resistances for all impact angles. Moreover, the effectiveness of plating was the highest for an impact angle of 45o , where the erosion and erosion-corrosion resistances were increased by 60% and 70% respectively, compared with that of the substrate. The results showed also that the coated and blank specimens behaved as ductile materials under erosion and erosioncorrosion tests and the maximum weight loss occurred at an impact angle of 45o .

This paper proposes a robust H2 feedback controller design for damping power system oscillations over a wide range of operating conditions. Robust H2 control technique based power system controller is developed for both excitation system and speed governor control. The effectiveness of the proposed power system controller is validated by a simple power system composed of a synchronous generator connected to an infinite bus through a transmission line. A comparison between power system responses at variety of operating conditions using the proposed H2 controller and Linear Quadratic Regulator LQR control is obtained. The digital simulation results prove the powerful of the proposed power system controller based on H2theory in terms of fast power system mechanical oscillation damping over a wide range of operating conditions with system uncertainty and parameters change.

In this paper a system identification toolbox for MATLAB is introduced, including a user friendly graphical user interface. The toolbox is appropriate for the identification of systems in discrete-time linear parameter varying (LPV) form. Using LPVIOID1 it is possible to identify input-output models in open-loop and closed-loop settings based on experimental data. It comprises several recent LPV identification techniques. Furthermore, a novel method for identifying unstable plants in closed-loop is proposed. The toolbox is equipped with several tools for model validation. Examples for illustration are included.