The rapid development around the Malacca city has a huge impact on the environment. Among the effects that can be seen is water pollution along the Malacca River. To overcome the problem, Hydro Quality Monitoring System (HydroQS) has been built and is a co-developed product between Universiti Teknikal Malaysia Melaka (UTeM) and Perbadanan Pembangunan Sungai dan Pantai Melaka (PPSPM). This device acts as one of the solutions to continuous monitoring the river water quality in real time values such as pH, Dissolved Oxygen (DO), Total Dissolved Solid (TDS), Turbidity and Temperature via Arduino interface. Prior to conduct field test, the HydroQS will perform floating and sensors functionality test at laboratory environment. As a results, the HydroQS capable to float and the sensors able to capture the water quality data.

Engine coolant plays an important role in maintaining optimal engine performance, where it has good effectiveness and can prevent corrosion in the engine cooling system (radiator). This study aims to determine the effect of the use of coolant variations (engine coolant) on the effectiveness of engine cooling (radiator) and to determine the effects of the coolants on the corrosion rate. To achieve this, coolant variations were used in the forms of mineral water, radiator coolant (prestone), and power coolant (TOP 1), which were applied at engine speeds of 1000, 1500, and 2000 rpm. Temperature data collection at the coolant inlet and outlet was carried out every 10 min at different rpm. The corrosion rate test used the AA 3102 series aluminum radiator material, which was tested using the potentiodynamic polarization method. The results showed that the best coolant effectiveness value was found for the power coolant (TOP1). This is influenced by the ethylene glycol contained within it, which helps to accelerate the decrease in temperature in the engine. The lowest corrosion rate was found for the power coolant (TOP1), with a corrosion rate value of 0.0074480 mm/year. This is because the power coolant (TOP1) contains organic carboxylate rust inhibitors, which can inhibit corrosion.

This research investigates the influence of layer thickness, laser power, and sintering orientation on the mechanical properties of aged Polyamide-12 (PA-12) FS3300PA using the Selective Laser Sintering (SLS) 3D printing method. Specimens were sintered with three different layer thicknesses, laser powers, and sintering orientations using SLS. The study also aimed to examine the resulting powder morphology, mechanical properties, and tensile fracture behaviors of the aged (more than eight continuously sintering cycles) and virgin FS3300PA powders. The specimens divided into ten groups: nine groups of aged powder and one group of virgin powder as a benchmark. The nine groups of aged powder were sintered with three different layer thicknesses (0.07 mm, 0.12 mm, and 0.15 mm), laser powers (65 W, 70 W, and 75 W), and orientations (YZY 0°, YZY 90°, and XYY 0°). The selections of these laser power and layer thickness values for the sintering setting are due to machine and material parameter limitation. The results from these parameters then compared with those of the virgin powder, which sintered using the parameters provided by the manufacturer, in terms of powder morphology, mechanical properties, and tensile fracture behaviours. Observation made using scanning electron microscope (SEM) revealed that there were not many changes in shape, size, and distribution between the virgin and aged powder, but slightly larger sizes and the presence of cracks found in the aged powder. The tensile strength, elongation at break value, and Young’s modulus all shared a similar trend, increasing with higher laser power but decreasing with increased layer thickness. Regarding the fracture morphologies, the number of pores and dimples decreased with increased laser power but increased with thicker layer thickness. There was also the occurrence of un-molten powder, especially in specimens sintered at the YZY 90° orientation with lower laser power and thicker layer thickness.