Plastic injection moulding is one of the most important polymer processing operations in the plastic industry today. However, lack of skill in mould making and injection moulding machine control will lead to defective plastic product. Warpage is one type of defect that usually appears in products with thickness less than 1 mm.This project is going to fabricate a mould that produced a thin plate with dimension 120 mm × 50 mm × 1 mm. The thin plate will be used for warpage testing. In mould fabrication, the mould base that purchase will be machined and assembled. After that, the mould is fixed on the injection moulding machine. The machine setting should be made to produce the product. Then, the product will be used for testing on the effective factors in warpage problem by applying the experimental design of Taguchi method.From the results, it shows that the most effective factor on the warpage is melt temperature. The filling time only slightly influenced on the warpage. The optimum parameters that can minimize the warpage defect are melt temperature (240 • C), filling time (0.5 s), packing pressure (90%) and packing time (0.6 s).

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Construction projects are always problematic and difficult to manage in certain stages. Management in construction industry has been characterized as being weak, insufficient, nebulous, backward and slow to react against changing conditions. This study aims to identify risk and cost managed in the change management of the construction projects. Quantitative study is organized and questionnaire as an instrument is used to collect the information from the construction experts in Klang Valley, Malaysia. Random sampling techniques is used to collect the data, 105 questionnaires are distributed and 90 ones are returned. The correlation analysis shows significant relationship between cost, risk and change management. The reliability test indicates satisfactory result to continue the questionnaire where Cronbach coefficient alpha value exceeds the level of 0.70. The study finds that design changes, client and contractor related changes are mostly occurred in change management of construction projects. Tendering on the basis of an incomplete design, which then changes during the course of the construction has been found as the key reason of the changes. Through a paper based exercise, site memorandums (SM), quoted rates (QR), variation orders (VO) and monthly payment certificates (MPC) are the activities managed by the engineers. Proper planning is the most leading change management in the risk management. Implementation of risk management was found the applied risk management in practice to hindrances. Since this is very vast debated subject, the study has recommended further investigation to include consultant firms for better understanding of the design changes leading to the cost and risk associated.

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