Rainfall can affect influent flow rate and compositions of wastewater, and thus further affect wastewater treatment performance and the effluent quality. This study aims to study the influence of rainfall on the environmental impacts of centralized wastewater treatment plants. The correlations between rainfall, and influent flow rate and compositions of wastewater in wet and dry seasons with two sewer systems, i.e. combined and separate sewer systems, were primarily established. Environmental impacts were assessed with life cycle assessment (LCA) to understand the temporal environmental burdens in wet and dry seasons. Functional units as per m 3 treated wastewater (FU1) and as per kg PO 4 3 -eq. removed (FU2), respectively, were used to evaluate impacts of wastewater treatment to the environment. Strong correlation between rainfall and the influent flow rate was found in the wastewater treatment plants with either a combined sewer system (with Pearson correlation coefficient r at 0.66) or a separate sewer system (with r at 0.84), where r represents the strength of the association between two variables. The rainfall effect is more obvious on the eutrophication potential and global warming potential than on other environmental indicators while sewer system, i.e. combined or separate, seems not important in the two cases studied. Both wastewater treatment plants (WWTPs) show a lower environmental burden in the wet season than in the dry season partially due to the dilution of wastewater by using FU1. The WWTP receiving high strength wastewater, however, demonstrates higher environmental impacts in the wet season by using FU2 than FU1, due to the less efficient treatment caused by heavy rainfall. Meanwhile, it is found that environmental impacts from the WWTP receiving low strength wastewater have no difference when using either FU1 or FU2. The results indicate that the environmental burdens particularly eutrophication and global warming caused by WWTPs are dependent on the correlations of rainfall intensity with wastewater quantity and quality instead of combined or separate sewer system. This could be used to guide a stricter control of eutrophication in a more sensitive season in more vulnerable receiving waters.

Although nutrient removal and recovery from municipal wastewater are desirable to protect phosphorus resource and water-bodies from eutrophication, it is unclear how much environmental and economic benefits and burdens it might cause. This study evaluated the environmental and economic life cycle performance of three different upgraded Processes A, B and C with commercially available technologies for nutrient removal and phosphorus recovery based on an existing Malaysian wastewater treatment plant with a sequencing batch reactor technology and diluted municipal wastewater. It is found that the integration of nutrient removal, phosphorus recovery and electricity generation in all upgraded processes reduced eutrophication potential by 62-76%, and global warming potential by 7-22%, which, however, were gained at the cost of increases in human toxicity, acidification, abiotic depletion (fossil fuel) and freshwater ecotoxicity potentials by an average of 23%. New technologies for nutrient removal and phosphorus recovery are thus needed to achieve holistic rather than some environmental benefits at the expense of others. In addition, the study on two different functional units (FU), i.e. per m 3 treated wastewater and per kg struvite recovered, shows that FU affected environmental assessment results, but the upgraded Process C had the least overall environmental burden with either of FUs, suggesting the necessity to use different functional units when comparing and selecting different technologies with two functions such as wastewater treatment and struvite production to confirm the best process configuration. The total life cycle costs of Processes A, B and C were 10.7%, 29.8% and 28.1%, respectively, higher than the existing process due to increased capital and operating costs. Therefore, a tradeoff between environmental benefits and cost has to be balanced for technology selection or new integrated technologies have to be developed to achieve environmentally sustainable wastewater treatment economically.

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Student-centered learning (SCL) is one of the teaching methods commonly used nowadays as it encourages the active participation and engagement of students in the classroom, especially for the engineering theoretical subject. This study is aimed to examine the factors of students’ involvement and participation towards the SCL Teaching Method in terms of the activities, benefits, problems, and limitations of student involvement. The quantitative data are obtained from the responses of students that enroll in an engineering theoretical subject in the Universiti Teknologi MARA (UiTM) Pahang Civil Engineering Diploma Program. These questionnaires were being classified into five major factors that are the formation of group studies for SCL activities, activities conducted for SCL teaching method, benefits that they gain from SCL method, problems that they encounter during SCL, and suggestions for student improvement towards the activity SCL session. The collected data were analyzed quantitatively by using the percentage and mean method in SPSS computer software. The Relative Importance Index (RII) system was used to quantify the relative importance of involvement factors. This study revealed three main factors affecting the participation and engagement of students in the classroom. This study has an important contribution to help academicians to improve and enhance their teaching method to achieve the objective of the SCL method in the future.

Abstract. Small and Medium Enterprises (SMEs) in Malaysia have gained a prominent role as the significant contributor to the economic growth. However, the world nowadays is heading towards economic downturn. The stability of macroeconomic variables promotes profitability of SMEs which propels them to a stage where they can access financing for sustaining growth. Therefore, it is apparent that the behaviour of the macroeconomic variables plays a major part in determining the nation's backbone in surviving the economic downturn. The objective of this study is to evaluate the impact of macroeconomic variables on the profitability of SMEs in Malaysia using multiple regression analysis. The findings revealed that the exchange rate has a small positive impact on SME GDP growth rate (10.81%), the interest rate has a strong positive impact (60.74%), while the inflation rate has a strong negative impact (-53.89%). Therefore, it can be concluded that the interest rate and inflation rate have significant impacts on the profitability of SMEs in Malaysia.