This paper presents the comparative study of design efficiency of two different brands of products, performing the same function using the Design for Manufacturing and Assembly (DFMA) method. The study aims to compare the products on the relative design efficiency. The DFMA method was used as it is a well-established technique for improving the efficiency of the product leading to minimizing production costs. It also shortens product development time by reducing the number of components in a product. The study used two different brands of dry iron as a case study. The result shows that the percentage of the design efficiency of dry iron A is 8.82%, whereas it is 10.34% of dry iron B. Thus, the dry iron B is much better as compared to A in term of its assembly operation and design efficiency. Therefore, the dry iron B is greener than dry iron A. Furthermore, a redesign of dry iron B was proposed and analyzed for the internal validation. The DFMA analysis result shows that the percentage of design efficiency of a new conceptual design of dry iron B increased to 18.08%. The application of the DFMA method to enhance the eco-friendliness of a product has been proven to be highly useful in design work.

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The nozzle of a 3D printer extrudes molten filament onto the print surface. The detachable and adjustable nozzle of a 3D printer allows for the printing of lines of varying thickness. This study intends to investigate the effect of nozzle diameter on the tensile and flexural properties of printed specimens. The tensile and flexural specimens were prepared according to ASTM D638 Type 1 and ISO 178, respectively. After specimens were printed with nozzles having diameters of 0.3, 0.4, 0.5, 0.6, and 0.8 mm, tensile and flexural tests were conducted using an Instron 5585 machine. Each specimen was printed with 0.2 mm layer thickness, a line pattern, and 100 percent infill. Tensile and flexural behaviors of PLA specimens were comparable, according to the findings. Tensile and flexural strengths increase as nozzle diameter increases, but they are only effective up to a certain diameter. At a nozzle diameter of 0.6 mm, the maximum tensile strength was 33.32 MPa, and at a nozzle diameter of 0.5 mm, the maximum flexural strength was 76.76 MPa. The flexural strength decreases when using nozzles with diameters of 0.6 and 0.8 mm, and the tensile strength decreases when using a nozzle with a larger diameter (0.8 mm). Because the diameter of the nozzle has a significant impact on the mechanical properties of a part, it is crucial to choose the correct nozzle diameter for optimal mechanical properties.

Abstract. Tremendous studied had been conducted on small hydropower system based on run-of-river schemes as an alternative renewable energy. Small hydropower system can be classified based on electricity generated between 1MW to 10MW. This system is normally being applied in rural area for providing the consumer electricity demand. Basically the researches to date are more focusing on the large scale of hydropower rather than the small scale hydropower technology. Therefore, this study is aimed to focus on predicting the available power generated by the small hydropower system specifically for the river stream in peninsular Malaysia. The water flow rate is measured by using ultrasonic level sensor located at the intake of the small hydropower system. The water flow rate is important data to be used in predicting the power output of the power house. The result shows that, the power outputs are depending on the fluctuation of water flow rate and the electricity being generated is more than 1MW. This finding can be used as the benchmark for daily and monthly monitoring process of the system efficiency or target output.

This paper aims in identifying effect of constraint point against critical area of 1300 cc national car steering knuckle using finite element method. The material of this steering knuckle is cast iron ASTM A536. The steering knuckle is modeled using a computer aided design software and the dimensions is assigned according to 3D scanning files. Meanwhile, steering knuckle is simulate using commercial finite element software where the load is assigned based on three conditions of constraints. The three conditions are fixed at hub, fixed hub and brake clamp and fixed at hub, brake clamp and steering arm of steering knuckle. Result shows that the positions of constraint points are significantly effect on stress value of steering knuckle. By acknowledging the presence or absent the effect of constraint on steering knuckle will aid in detecting critical area on this steering knuckle. Thus, approach could be conducted to optimize and enhance the life cycle of a steering knuckle. The data will be further utilized in testing the steering knuckle under variable amplitude strain signal.