27 research outputs found

    Synthesis Of Fatty Acid Methyl Esters (FAME) From Palm Oil Via Non-Catalytic Supercritical Fluid Reaction

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    Palm oil is abundantly available in Malaysia and has been shown to be a promising feedstock in fatty acid methyl esters (FAME) or biodiesel production compared to other vegetable oils. In the present study, palm oil was utilized as the source of triglycerides in supercritical fluid reactions. The solvents that were investigated in this study were methanol, methyl acetate and dimethyl carbonate. An experimental system was successfully designed and fabricated for supercritical fluid (SCF) reaction. The non-catalytic SCF reactions were carried out with reaction temperature varying from 300°C to 400°C, molar ratio of solvent to oil from 10 to 50 mol/mol and reaction time of 5 to 60 minutes

    Oil Palm Biomass As A Sustainable Energy Source: A Malaysian Case Study.

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    The latest scientific data confirmed that the earth's climate is rapidly changing. Therefore, it has been widely accepted worldwide that global warming is by far the greatest threat and challenge in the new millennium. The main factor that causes global warming is the release of greenhouse gases to the environment

    The predominant learning approaches of medical students

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    Background By identifying medical students’ learning approaches and the factors that influence students’ learning approaches, medical schools and health care institutions are better equipped to intervene and optimize their learning experience. The aims of our study is to determine the predominant learning approach amongst medical students on a clinical posting in a hospital in Singapore and to examine the demographic factors that affect their learning approach. Methods The Approaches and Study Skills Inventory for Students (ASSIST) questionnaire was administered to 250 medical students from various medical schools on clinical attachment to the Obstetrics and Gynaecology (O&G) department of KK Women’s and Children’s Hospital (KKH) Singapore between March 2013 and May 2015 to determine students’ predominant learning approaches. Multinomial logistic regression was used to examine the association between demographic factors (age, gender and highest education qualification) and predominant learning approach. A cut-off of p \u3c 0.05 was used for statistical significance. Results Amongst 238 students with one predominant learning approach, 96 (40.3%) and 121 students (50.8%) adopted the deep and strategic approach respectively, whilst only 21 (8.8%) adopted the surface approach. Male students appeared less likely to adopt the strategic learning approach than female students (p value = 0.06). Predominant learning approaches were not influenced by demographic characteristics such as age, gender and highest educational qualifications. Conclusions This study provided insight into the learning approaches of a heterogeneous group of medical students in Singapore. While it is encouraging that the majority of students predominantly utilised the deep and strategic learning approach, there was a significant proportion of students who utilised the surface approach. Interventions can be explored to promote deeper learning amongst these students

    The LHCb upgrade I

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    The LHCb upgrade represents a major change of the experiment. The detectors have been almost completely renewed to allow running at an instantaneous luminosity five times larger than that of the previous running periods. Readout of all detectors into an all-software trigger is central to the new design, facilitating the reconstruction of events at the maximum LHC interaction rate, and their selection in real time. The experiment's tracking system has been completely upgraded with a new pixel vertex detector, a silicon tracker upstream of the dipole magnet and three scintillating fibre tracking stations downstream of the magnet. The whole photon detection system of the RICH detectors has been renewed and the readout electronics of the calorimeter and muon systems have been fully overhauled. The first stage of the all-software trigger is implemented on a GPU farm. The output of the trigger provides a combination of totally reconstructed physics objects, such as tracks and vertices, ready for final analysis, and of entire events which need further offline reprocessing. This scheme required a complete revision of the computing model and rewriting of the experiment's software

    Valorization of palm oil mill effluent via enhanced oil recovery as an alternative feedstock for biodiesel production

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    Residual oil from palm oil mill effluent (POME) can be valorized into value-added products like biofuel. However, the complex structure in POME limits the full recovery of intracellular lipids. To address this challenge, low-frequency ultrasonication was used as a pre-treatment prior to oil recovery to improve the yield by liberating the entrapped oil via the cell disruption technique. This study focused on optimizing the ultrasound conditions (i.e., ultrasonication amplitude, ultrasonication duration, and probe immersion depth) to maximize the improvement of oil recovery yield using response surface methodology. The optimized conditions were 30.074% ultrasonication amplitude, 0.167 min ultrasonication duration, and 2 cm probe immersion depth. This resulted in an additional 42.50% improvement in oil recovery yield over non-ultrasonicated POME, which is in close agreement with the model prediction. Additionally, a cost–benefit analysis was incorporated to determine the feasibility of ultrasonication for enhancing oil recovery. The study also explored the synthesis of biodiesel from POME-recovered oil and characterized the fuel attributes according to American Society for Testing and Materials- and European Standards-prescribed procedures. The attributes of biodiesel produced from POME-recovered oil are comparable to those of palm-based biodiesel in Malaysia, demonstrating its potential as an alternative source for biodiesel production. HIGHLIGHTS An optimized study for ultrasound-enhanced oil recovery from palm oil mill effluent (POME) using response surface methodology was conducted.; Cost–benefit analysis revealed that ultrasound pre-treatment is a viable process.; POME-recovered oil was used for biodiesel production via a two-step esterification and transesterification process.; Biodiesel produced from POME-recovered oil met the fuel characteristics requirement of local and international standards.

    Role of energy policy in renewable energy accomplishment: The case of second-generation bioethanol

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    Renewable energy has been in the limelight ever since the price of crude petroleum oil increases to the unprecedented height of US$96 per barrel recently. This is due to the diminishing oil reserves in the world and political instabilities in some oil-exporting countries. The advantages of renewable energy compared to fossil fuels are enormous in terms of environment and availability. Biofuels like bioethanol and biodiesel are currently being produced from agricultural products such as sugarcane and rapeseed oil, respectively. Collectively, these biofuels from food sources are known as first-generation biofuels. Although first-generation biofuels have the potential to replace fossil fuels as the main source of energy supply, its production is surrounded by certain issues like tropical forests' destruction. Instead, second-generation bioethanol, which utilizes non-edible sources such as lignocellulose biomass to produce ethanol, has been shown to be more suitable as the source of renewable energy. However, there are challenges and obstacles such as cost, technology and environmental issues that need to be overcome. Hence, the introduction of energy policy is crucial in promoting and implementing second-generation bioethanol effectively and subsequently become a major source of renewable energy.

    A comparative study on the energy policies in Japan and Malaysia in fulfilling their nations' obligations towards the Kyoto Protocol

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    Global warming and the associated changes in the world climate pattern have been accepted world wide as the gravest threat to humanity in the 20th century. To mitigate the impacts of global warming, the Kyoto Protocol was established in 1997 with the objective of reducing global greenhouse gases (GHGs) emission, in particular carbon dioxide (CO2), by 5.2% below 1990 levels. Developed nations that ratified the Protocol are committed to GHG reduction targets while developing nations are encouraged to reduce GHG emissions on a voluntary basis. Since most of the GHGs emissions come from the energy sector, energy policy plays an important role in fulfilling the Kyoto Protocol obligations. This year marks the beginning of the commitment period for the 2012 Kyoto Protocol. In this case, it would be worthwhile to compare the energy policies in Malaysia and Japan as these nations move towards fulfilling their obligations towards the Kyoto Protocol; bearing in mind that both countries ratified the Protocol, but that Japan commits a reduction target of 6% while Malaysia bears no obligation. Based on the comparison, recommendations were made on how a developing nation like Malaysia could adopt the policies implemented in Japan to suit local conditions and contribute significantly to GHG reduction.Energy policy Greenhouse gases Energy efficiency

    Banana biomass as potential renewable energy resource: A Malaysian case study

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    The world has been relying on fossil fuels as its primary source of energy. This unsustainable energy source is not going to last long and thus, gradual shift towards green renewable energy should be practiced. In Malaysia, even though fossil fuel dominates the energy production, renewable energies such as hydropower and biomass are gaining popularity due to the implementation of energy policies and greater understanding on the importance of green energy. Malaysia has been well endowed with natural resources in areas such as agriculture and forestry. Thus, with the availability of feedstock, biomass energy is practical to be conducted and oil palm topped the ranking as biomass source here because of its high production. However, new sources should be sought after as to avoid the over dependency on a single source. Hence, other agriculture biomass should be considered such as banana plant biomass. This paper will discuss on its potential as a new biomass source in Malaysia. Banana plant is chosen as the subject due to its availability, high growth rates, carbon neutrality and the fact that it bears fruit only once a lifetime. Conversion of the biomass to energy can be done via combustion, supercritical water gasification and digestion to produce thermal energy and biogas. The theoretical potential power generation calculated reached maximum of 950 MW meeting more than half of the renewable energy requirement in the Fifth Fuel Policy (Eighth Malaysia Plan 2001-2005). Thus, banana biomass is feasible as a source of renewable energy in Malaysia and also other similar tropical countries in the world.Banana Biomass Energy

    Identification and Robust Tracking Control of a Single-phase Rotary Motor with Halbach Permanent Magnet Array Design

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    The single-phase electromagnetic motor with the circular permanent magnet Halbach array design, has advantage of large force constant compared with its 3-phase counterpart, if the rotation is within 60 degrees range from its neutral position. However, to authors' best knowledge, no existing literature mentions on tracking control application using such a single phase rotary motor, probably due to its angular dependent force sensitivity. This paper first models a typical two-pole single phase rotary motor with Halbach circular array, with consideration of back-EMF, friction torque and position dependent characteristic. Followed by this, a dual-relay configuration is applied to closed-loop identification of model-parameters by limit cycle experiments. Later, a composite controller, composes of a model-based controller, a time-delay controller and a sliding mode controller, is capable to achieve the high-speed tracking of reference trajectory with presentation of model uncertainty and disturbances. Simulation based on the actual design parameters shows the practical appeal of the proposed approach
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