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The current study is presented into the investigation of the application of ultrasonic vibration on the lower punch during compaction process of powder metallurgy material. The lower punch is specifically designed of ultrasonic horn which has been tuned at frequency of 20 kHz and vibrates in longitudinal mode. Finite Element modeling was used to assist the design process of the lower punch or horn. The horn was fabricated using high grade aluminium alloy and mounted onto the ultrasonic system test rig and subsequently tested prior the experimental process begins. Various static and ultrasonic compaction procedures have been carried out to confirm the capability of the tool to operate. The compaction force was reduced significantly at the onset of ultrasonic vibration applied compared to without ultrasonic.

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This paper reports on the development of predicted mathematical model for cutting force (Fc) during side milling of medium density fiberboard (MDF) using uncoated carbide insert. Box-Behnken design (BBD) of experiment, coupled with response surface method (RSM) were employed to establish the cutting force model. Evaluation on the effects and interactions of the machining variables on the cutting force were carried out. The machining variables involved include spindle speed, feed rate, routing width and were denoted by A, B and C respectively. Statistical analysis conducted on the experimental results indicated that the mathematical model for cutting force was adequate within the limits of factors being investigated. After eliminating the insignificant factors or model terms in the reduced model, it was found that factors A, B, C, B2 (second order of B), C2 (second order of C), were the most significant factors affecting the cutting force. BC (interaction of B and C) and AC (interaction of A and C) are the subsequent significant factors. Three-dimensional plots displaying the interactions between these significant factors were presented. The reduced model was then verified experimentally and statistically using ANOVA. It was evident that Box-Behnken design proved to be an efficient tool in identifying and constructing maps of interactions between the significant factors. Experimental results showed that lower cutting force can be obtained by employing higher cutting speed, low feed rate and lower routing width when side milling MDF using uncoated carbide insert.

Implementation of computer simulation analysis of proposed Temephos submerged dispensers designated as “Floater 1” and “Floater 2” presented in this study contributes to a body of research on the types of interventions used to prevent mosquito-borne diseases. Floaters 1 and 2 are known as cage and cylindrical design, respectively. Modal analysis conducted on both design enabled the authors to further understand and visualize the deformation and stress distribution which correspond to natural frequency of each design. Obtained natural frequency of these dispensers could avoid destructive frequencies caused by external loads acting on both designs. Furthermore, costs related to destructive testing and manufacturing defects would literally be avoided. Hence, a more robust and affordable mosquito control product will potentially be materialized. Combined usage of these submerged dispensers made of polylactic acid (PLA), an environmentally friendly plastic printed via 3D printing with reused or recycled plastic material will gain a widespread use and contribute to the environmental sustainability.