One of the major challenges facing our water utilities is the high level of Non-Revenue Water (NRW) in the distribution networks. This paper assessed the performance of current management practices by Syarikat Air Melaka Berhad (SAMB) to deal with NRW. Information and NRW management data (from 2012 to 2013) were gathered and analysed. Statistical methods were used to evaluate the effects of pipe length and number of connections of the distribution network to the leakage level; and to determine the causes of leakage (water loss). In 2014, Melaka’s NRW percentage was 21.4% as compared to the national average of 35.6%, which is the second lowest rate among the states in Malaysia. Results of the study revealed significant positive relationships between average MNF (L/s) with number of connections and pipe length, with the prediction model of average MNF (L/s)=-4.42+1.088*10-2(NC)+1.07*10-4(PL), R2= 73.19%. The results also indicated that in a compact and urbanized city like Melaka, number of connections in the network appears to be most influential to the average MNF (water loss) (shown by a strong positive relationship, r = 0.847) as compared to the less compact zone (such as Perak) where pipe length appears to be more influential.

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Public knowledge, awareness and behaviour on climate change are crucial to prevent climate change. This study investigates the level of knowledge, awareness and behaviour of Malaysian society on the impact of climate change (Case study in Klang Valley). Adopting a descriptive survey research design, a self-designed questionnaire entitled "Climate Change Awareness” was conducted on a sample of 467 respondents from three (3) main groups (university students, public and government servants). Cronbach's alpha (α) for this study is 0.749, indicating an acceptable level of internal reliability of the scale with this specific sample. The finding indicates that most of the respondents have an average level of knowledge (41.22%) from different levels of education. The level of awareness and behaviour among the respondents was also very weak and fragile. Approximately 55.3% of respondents are not aware of the impact of climate change on the environment, economy and human health. Although the government has promoted its initiatives and policy regarding climate change, it cannot be presumed that the society is having a high level of knowledge awareness and behaviour about climate change. In addition, this study also measured the effectiveness of the national policy on climate change in Malaysian society. This study offers the decision makers some fundamental insights regarding public knowledge, awareness and behaviour towards climate change that could potentially assist in promoting responsive policies and strategies to reduce the impact of climate change.

Fermentation is commonly used to produce food materials (beverages, dairy products), renewable fuels (hydrogen, ethanol), pharmaceuticals (antibiotics) and industrial chemicals (acetate, butyrate). In industrial fermentation, a specialised, pure microbial culture is normally used to generate specific products. This requires expensive, sterile production conditions with high-quality raw materials. In contrast, Mixed Culture Fermentation (MCF) uses environmentally ubiquitous organisms to produce a mixture of products depending on the environmental conditions. As they are sourced from the environment, mixed cultures do not require expensive culture maintenance. In addition, they are capable of dealing with a mixture of substrates of variable composition and non-sterile feeds. This has the potential to reduce costs, increase reactor loading rates, and allow for continuous reactors, as opposed to batch operation. MCF is a preferable, flexible process in that can continuously manipulate product mixtures by changing operational condition. The key limitation to industrial implementation of MCF is the difficulty in predicting product formation based on operational conditions. This is due to a lack of understanding of how operational factors affect the various pathways, and hence the product spectrum, with pH being the most commonly manipulated process variable. This thesis attempts to further analyse the link between operational conditions, microbial community, and product spectrum. Two experiments were done, the first focusing on mode of pH manipulation in a continuous reactor, and the second focusing on batch operation at different pH levels, and with different inoculums. The continuous study varied pH from 4 to 8, with one experiment varying the pH from 4 to 8 progressively (progressive), and the other resetting pH back to 5.5 as an intermediate point (reset). The reset regime resulted in a highly dynamic community, shifting from Clostridia at low pH to Klebsiella, and a more dynamic product spectrum, with specifically ethanol being produced at high pH. The progressive regime resulted in relatively flat microbial community, with less dynamic product spectrum. Kinetic experiments done on the same reactors, varying also hydrogen partial pressure through nitrogen sparge rate, and using a membrane inlet mass spectrometer (MIMS) as measurement technique emphasised a number of time constants, including direct chemical response to pH change (1000 d -1 ), liquid and gas response to changes in gas flow and to pH change, likely related to mass transfer characteristics (100 d -1 ), and biological responses, mainly measured as ethanol (1 d -1 ). Changes in microbial community are even slower than this. The second batch indicated that the major factor ii influencing rate and spectrum response was the inoculation pH, with biomass inoculated at pH4 being very slow in batch (1 d -1 ), and producing mainly ethanol, and biomass inoculated at higher pH levels being pH 6 (3 d -1 ) and 8 (10 d -1 ) being progressively faster. T...