Aims: To examine the viability of Soybean Oil as a feedstock for Biodiesel production by carrying out its characterization and examining its thermodynamic properties to see if they are within ASTM limits. Study Design: Place and Duration of Study-The production was conducted in the Department of Mechanical Engineering of the University while the characterization of the Biodiesel was conducted at the Postgraduate Research Laboratory. Samples of Glycine ma (L.) merril were obtained from a local market in the Akure town of Ondo State, Nigeria in October of 2014.  Methodology: Oil Extraction-The oil was extracted using soxhlet extractor, but before extraction the soybeans were crushed in a blender to increase the area exposed to the petroleum ether solvent. The extraction flask was dried in an oven at 105°C and the weight was measured after cooling. 2.5 g of soybean was poured into the flask and leached for 5 hours after which extraction flask was removed from the mantle heater after all the petroleum ether was removed with rotary evaporator and the oil was oven dried at 105°C for one hour to remove any water present. The flask was finally cooled to room temperature in a desiccators and the weight of the flask and dried oil was again measured. Transesterification and Glycerine Analysis Process: 50 mg of the extracted oil was esterified 5 times at 95°C with 3.5 ml of the 0.5 M KOH of dried methanol. The mixture was neutralized using 0.7M HCL. 3 ml of 14% boron triflouride in methanol was added and the mixture was heated for 5 minutes at 90°C to achieve completed methylation process. The fatty acid methyl esters were thrice extracted from the mixture with redistilled methanol. The content was concentrated to 1mL for gas chromatography analysis and 1 µL was injected into the port of the Gas Chromatograph analyzer. Results: most of the pertinent parameters for the determination of validity were found to be within ASTM limits, namely: Flash Point (135°c / 130°c min); Kinematic Viscosity (4.80 / between 1.9 - 6); Cetane number (55 / 47 min); Copper Strip Corrosion (1 / 3 max); %Carbon Residue (0.12 / 0.050); %Sulphated Ash (0.044 / 0.020). Conclusion: Given the obviously good numbers associated with the study relative to ASTM standards, Soybean is a viable source of Biodiesel. However, further study could explore the use of Soybean chaff and other waste matter obtainable from it rather than the entire crop.

Aircraft arrival at airports is limited by the physical configuration and layout of the terminal maneuvering area (TMA), which might result in a bottleneck. In a bottleneck situation, navigation is made difficult because arriving aircraft will need special considerations to manage congestion and guarantee safety. In addition, the operating cost of airline operators increases with higher fuel consumption encountered in the extra airborne time. Likewise, passengers incur more travel time with the additional arrival delays. Traditional arrival adopts conventional standard arrival route (STAR), with trajectories that are rigidly coordinated by air traffic controller (ATC). However, a more flexible approach to general navigation has also been introduced, namely the area navigation (RNAV), which makes provision for flexibility in aircraft path selection. This flexibility is enabled by abstract navigational elements, namely waypoints that are unlike conventional navigational aids (NAVAIDs). We look at a modeling framework that juxtaposes the key elements of the traditional STAR (procedure-based) navigation and RNAV (performance-based) navigation. We adopt the cellular automata (CA) framework that has the capability to model the dynamic interaction between aircraft, inherent environmental uncertainties, and arrival route as defined by waypoints. To this end, we develop a modeling environment that enables a fair comparison between these two approaches under similar conditions to determine their respective viability. The effect of the number of waypoints in the TMA under different traffic conditions is illustrated using the relationship between TMA occupancy, traffic flow, and the landing rate. Results show that RNAV navigation exhibits more sensitivity to waypoint distribution within the TMA in terms of throughput, compared to STAR navigation. STAR navigation, on the other hand, demonstrates inherent latency that allows for higher capacities, albeit at the risk of initiating abrupt jamming when a high number of waypoints are active. Consequently, we are able to establish guidelines that justify the adoption RNAV over STAR and vice versa. Furthermore, we also identify performance disparities between them, and where each approach is desirable.

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The widespread adoption of Unmanned Aerial Vehicles (UAVs) can be traced to its flexibility and wide adaptability to various operating conditions and applications, comparably low cost of construction and maintenance and environmental friendliness as they can be easily configured for electric power. The use of electric power also favours its low noise applications such as surveillance. A major issue associated with surveillance, as addressed in this study is the compromise between Range and Endurance operation modes. The Range mode relates to being able to cover longer distances while the Endurance mode relates to spending longer times in the atmosphere for a fixed charge. Trying to balance the interplay of these parameters gave rise to a multi-objective optimization where the objectives are somewhat conflicting. This resulted in a set of Pareto solutions which are a set of design parameters (primarily angle of attack) that satisfy the joint requirements of the performance parameters of Range and Endurance. This study first considered a baseline aerodynamic design using traditional design methods. Design of Experiment techniques were then used to select the most favourable design points. This model was then used to build an input framework for Genetic Optimization algorithm deployed in the Global Optimization Toolbox of MATLAB. The result of this research shows that most of the region associated with medium angle of attack (AOA) setting (7 degrees) jointly satisfies good Range and Endurance performances with an average lift-to-drag ratio of 20 in the flight configuration considered. The implication of this result is that low velocity drag encountered in surveillance that requires a high AOA is largely reduced with the medium setting, albeit stabilized with other structural and aerodynamic settings, namely an aspect ratio of 13 and a taper ratio of 0.6.