Computational Fluid Dynamic (CFD) was used to simulate the injection molding process of a tray. The study focuses on pressure distribution and velocity drop during the injection process. CFD simulation software ANSYS FLUENT 14 was utilized in this study. The melt front pressure in the mold cavity shows that it was affected by the shape of mold cavity and filling stage. The melt front pressure will decrease as the flow move further than the sprue but it will increase rapidly when the mold was about to be fully filled. The slight pressure drop was detected when the molten flow meets the rib of the tray. The velocity of higher injection pressure was greater than the lower injection pressure but the velocity rapidly dropped when the melt front fully filled the cavity. The current predicted flow profile was validated by the experimental results, which demonstrates the excellent capability of the simulation tool in solving injection-molding problems.

TiCN and TiAlN coated twist drills were subjected to drilling tests to investigate the failure mechanisms during drilling operation. The drilling tests were performed on a carbon steel plate with a thickness of 25 mm and the depth of drill was set at 20 mm. The drill performance parameters were set at a spindle rotation of 1,600 rpm and feed rate of 20 mm/min. Each sample was then subjected to Scanning Electron Microscopy examination to investigate the wear mechanisms operated during drilling. Microstructural examination showed that the abrasion, adhesion and thermal wear mechanisms are operated during drilling process.

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3-D packaging is a technology that offers high density packaging and high performance. It enables chips to be stack in a single package and widely adopted in multi-media products. Thermosetting material is used for their encapsulation, is flowed through their thin space and wide filling area during package encapsulation process has become vital concern i.e. void formation. In this paper, such issue has been numerical studied due to the effect of transfer speed of the plunger head during encapsulation process. There are five transfer speeds of 1.6, 2.0, 3.4, 6.8, 9.04 mm/s have been chosen in order to investigate the quality of air entrapped (hereafter namely as void), where it degraded the package’s reliability. It is found that the longest transfer speed delivered to the best encapsulation process, which had lowest volume of air trap or void formation in the package.Keywords: Encapsulation, Transfer speed, Vent arrangement, Void Formation

This paper reviews the working principles and numerical approach for the synthetic jet cooling in the previous studies. It is essential to reviews relevant previous research within the study scope in order to further enhance the improvement of synthetic jet technology. Furthermore, numerical approach can cut the cost and save time compared to experimental works. Numerical simulation is crucial to expedite the synthetic jet product enhancement as it opens up big potential in electronic device application. Studies carried out by many scholars within the scope of this publication have demonstrated that resonance frequency enhances the performance of synthetic jet. Reynold numbers vary with frequency, and greater Reynold numbers produced higher heat transfer coefficients. The majority of researchers have also chosen the cylindrical cavity type because it offers superior velocity output, which improves cooling performance. According to previous studies, a smaller diameter leads to a higher velocity output and a higher Reynold number

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This paper presents the development of microcontroller based potentiometric transduction circuit for a continuous fluid level sensor. The purpose system involved the integration between hardware and software subsystem. For hardware subsystem, the design of potentiometric circuit was tested with theoretical computation, simulation on Proteus VSM software and breadboard circuit. This finding was then used to develop interface for the analog-to-digital converter. For software subsystem, the water level indicator system has been developed using ATMEGA2560 by converting the output from potentiometric circuit into water level with a look-up table. It computes the digital data conversion into desired reading and displays data through the second hardware subsystem which is liquid crystal display. A potentiometric indicator for a continuous fluid level sensor to detect level of water ponding on the flat roof was developed. It was comprised of a potentiometric transduction stage and follower stage. From the experiment, it was shown that the potentiometric circuit designed was able to report changes in the water in a different level. The integration of the continuous fluid level sensor with the potentiometric indicator system will have a significant impact on the practice of sensor integration.