Abstract: Austenitic stainless steel types AISI304 and AISI316 are material characterised by their high ductility and toughness. In this paper, the deformation characteristics of AISI316 and AISI304 stainless steel are investigated in a temperature range of 850-1050 °C and strain rate range of 0.001-0.1 s-1 using dilatometer hot compression tests. The tests aimed at producing hot processing map and TEM images of the alloys. Based on the deformation results, an empirical model is used to predict the behaviour of both alloys in terms of the stress/strain characteristics and the recrystallization dynamics. The developed model is considered to be a very good tool which can be used to predict the materials characteristics under predefined deformation conditions.

Abstract: Composites of Poly (vinyl alcohol) (PVA)/Chitosan (CS) have been synthesized and characterized successfully. Mechanical and degradation properties of composites also have been modified. PVA/CS composites prepared with different concentration ratio of PVA/CS (90%PVA/10%chitosan, 80%PVA/20%chitosan, 70%PVA/30%chitosan, 60%PVA/ 40%chitosan and 50%PVA/50%chitosan). FTIR shows the changed in intensity and bonding as well as shifting in peaks with increasing of CS, and sorbitol. SEM micrographs of composites surface showed that CS partially miscible with high ratio of PVA. Mechanical properties were characterized and the result indicates that tensile strength and modulus of elasticity increased with increasing CS ratio which associated with decreasing in elongation and flexibility of films. By adding sorbitol, the elongation at break has been improved. Weathering of composites showed high degradation rate with higher CS concentration. Degradation of composites has been affected by the addition of sorbitol. A numerical study was conducted for the PVA/CS, the study gives a closed results compared with the experimental values.

Abstract: This research is concerned with the study of the performance of a position control model used to determine the stroke of the pneumatic actuator driven by (ON/OFF) solenoids valve interfacing with linear position sensor. The proposed model involves two solenoids directional control valves, double acting pneumatic cylinder and electrical control subsystem conducted to proportional position controller unit. To achieve the position control system and to stop the rod of the cylinder at the set point it is required to implement a mathematical calculations as well as an experimental work to realize the best behavior of the system. A laboratory test rig has been set up including the required electrical and pneumatic apparatus for obtaining the practical results and to accomplish the suggested position control system. Simulation was carried out using MATLAB/SIMULINK and a comparison between the experimental and theoretical results was done to investigate the best behavior of the suggested model. The complete verification of the obtained results show that the ability to employ the proposed model with high efficiency.

Abstract: Malacca in Malaysia is a famous tourist attraction state that provided service of trishaw in all area at center of Malacca. It can see that some of the trishaw rider is very old enough to rider the trishaw. Additional, the trishaw rider sometime exhausted to cycle the trishaw because passenger is too heavy. The idea is to develop an automatic speed control for electric trishaw by applying closed loop speed control based on PID control. In a typical electric drive controller, there are usually several nested control loops for the control of torque, current, speed and position each of which may use a separate Proportional, Integral and Derivative (PID) controller [1]. Therefore, the PID controller will be implemented to an electric trishaw to solve the problem to improve the performance of the system. Desired speed will be based on paddle rotation speed which cycle by trishaw rider. DC motor has been installed at electric trishaw to drive the trishaw based on desired speed. DC motors are most suitable for wide range speed control application and are therefore used in many adjustable speed drives application [2]. Another reason using DC motor for electric trishaw is because it can provide the robust speed control and stability [3].

Abstract: This paper presents the development of a cutting force model for end milling process under various cutting conditions and the tool wear is measured by Scanning Electron Microscope (SEM).This novel approach combines the concept of experimental design and finite element modeling of the cutting process which allows for a fairly accurate prediction of cutting forces with a significantly lower computational cost. The milling experiments are performed by CNC milling machine with tungsten carbide tools. The test sample made of titanium alloy Ti-6Al-4V is prepared for testing. The cutting conditions are selected based on the toughness of the work piece with in the tool manufacturer’s recommended range for the work piece and tool geometry configuration. The cutting forces are measured by using dynamometer and compared the simulated results. In this modeling, the cutting tool and work piece are defined as per Taguchi design of experiments (DOE). In cutting approach, Deform 3D v 6.1 software is used to simulate the milling process.

Abstract: Thermal oxidation (TO) is one of the most important techniques in the field of surface modification to enhance the required properties of engineering materials. In the present study, the influence of TO process on the corrosion behavior of a commercial pure titanium (CP-Ti) was investigated. The oxidation process was conducted at different temperatures, i.e., at 500 and 800 oC for 8 h, in a muffle furnace with a controlled environment at atmospheric pressure. The characterization of modified surface layers was examined. It is found that TO process promotes the formation of adherent surface oxidized layers on the CP-Ti samples without spallation. The superior electrochemical performance is found in oxidized CP-Ti samples compared to untreated samples.

Abstract: A highly requirement of analyzing a biological sample at a so-called single cell level has encouraged for the development of innovative and versatile microdevices. Up to now, microfluidic devices have become as emerging technologies that can support an investigation and analysis of a living cell. For many cutting-edge single cell studies, trapping of individual cells at specific locations in the developed microfluidic device is truly essential prior to characterization or quantification of cells biophysical properties. In this paper, microfluidic devices capable of trapping a single cell are designed simply through a concept of hydrodynamic manipulation. The microfluidic devices are designed with a series of trap and bypass microchannel structures for trapping individual cells without the need for microwell, robotic equipment, external electric force or surface modification. Two designs of microchannel: 1) Loop-type and 2) T-type are proposed. In order to investigate the single cell trapping capability, a finite element model of the proposed design have been developed using ABAQUS-FEATM software in which the fluid velocity can be analyzed. Based on the simulation, the geometrical parameters which affect the single cell trapping are appropriately selected. After adapting the trap and bypass microchannel structures via simulations, a single cell can be trapped at a desired location efficiently. It is shown that the simulation results are in a good agreement with the previously reported experimental studies.

Abstract: A mathematical formulation of data-driven stochastic subspace identification (SSI) has been summarized and a code has been implemented for the modal parameter estimation of the ship structure. The implemented code has been verified and validated through the benchmark test of a rectangular plate, where the results have been compared with those of the commercial software. Then the code has been used to estimate the modal parameters of an oil tanker. The results show that the code operates well its function and provides stable solution by appropriately selecting key parameters related to the stability of the solution in data-driven SSI.

Abstract: The pool boiling phenomenon is used for the cooling of walls in several areas such as refrigeration and electrical energy production, in order to cope with the problems of thermal dissipation that limit significantly the current densities of operation. To quantify the thermal exchanges in pool boiling, we realized in one hand an experimental study of liquid nitrogen in steady and transient state regimes. This investigation has been realized on a brass ribbon in a horizontal position subjected to different heat flux densities. The results obtained allow to contribute to a better understanding of heat transfer in a nucleate boiling system and to highlight the nucleation phenomenon. On the other hand, a first numerical attempt is carried out to investigate the natural convection area in pool boiling. The heat equation is solved by the Finite-Differences method in order to model the temperature distribution of the ribbon, than the numerical results are compared with experimental data.