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In this paper, the mathematical model of free convection boundary layer flow of horizontal circular cylinder immersed in Ag/Water nanofluid and Al2O3-Ag/Water hybrid nanofluid are considered. The governing non-linear partial differential equations are first transformed to a more convenient way before being solved numerically using the Keller-box method. The numerical values for the reduced Nusselt number and the reduced skin friction coefficient are obtained and illustrated graphically as well as temperature profiles and velocity profiles. Effects of the Prandtl number, Eckert number and nanoparticle volume fraction are analyzed and discussed. It is found that the Nusselt number for Al2O3-Ag/Water hybrid nanofluid is comparable with Ag/Water nanofluid with a reduction in skin friction coefficient. The preliminary results reports here are important as a reference in exploring the potential of hybrid nanofluid to reduce the production cost compared to the used of metal nanofluid.

Eco-friendly car is expected to be the next driving market force for global transportation and technology due to its paramount importance towards the sustainability of the environment and society. However, the actual sales of eco-friendly car are not that convincing and it is even decreasing because the consumer is still uncertain to consider eco-friendly as one of the criteria for them to buy their cars. This situation is worsen by the lack of information and awareness regarding sustainability transportation initiatives. Due to the uncertainty and vague understanding of the consumer about this problem, this paper attempts to investigate the current preference of consumer to buy their cars, and whether they really need to buy the eco-friendly car by using the Fuzzy Analytic Hierarchy Process (FAHP) which implements the Intuitive Vectorial Centroid (IVC). Based on FAHP, the imprecise or fuzzy judgment from the decision maker can be incorporated, to anticipate a better decision for eco-friendly car selection. The outcome of FAHP is compared with crisp Analytic Hierarchy Process (AHP), and the findings shows that FAHP can provide an accurate and consistent result with AHP, although it deals with fuzzy judgment inputs from multiple decision makers.

As the global community is moving towards the usage of a cleaner technology, automotive industry has designed the car to become more environmentally friendly, or eco-friendly. Malaysia aims to produce 200,000 electric vehicles (EV) by the year 2020 but this effort might be halted due to the fact that electric vehicle’s sales is not promising for the time being. This research attempts to investigate the current preference of Malaysian to buy their car, and whether they really prefer to buy the eco-friendly car. An Analytic Hierarchy Process (AHP) model for Malaysian eco-friendly car selection is developed by this research which involves aggregated group judgment from 22 respondents. The result indicates that safety is the highest priority for the Malaysian to buy cars, followed by fuel economy, services, performance, affordable price, emission and design. Two of the criteria which are closely related with eco-friendly factor which are fuel economy is ranked at second whereas emission is ranked at sixth. This concludes that Malaysian still consider eco-friendly factor, which also justify the selection of AHP model for the best eco-friendly car to be Nissan Leaf (2016), followed by Hyundai Ionic HEV (2017), Mercedez Benz C350e (2016), Perodua Myvi 1.3 Ezi (2017), and Toyota Prius 1.8 VVT-i Active (TRK) Auto.