The transportation of heavy machine parts and equipment within and outside the workshop has been a source of concern and needs urgent attention because of the hazard it exhibits. This negative effect on the health of engineers, led to the invention of the floor jib crane but research shows that contemporary designs of floor jib crane fail over time when these static load is left on it for a prolonged period of time. This project is centered on the design and fabrication of a mobile floor crane equipped with a facility to lock the load at any level as a special feature, to tackle the issue of failure due to static load. The mobile crane is designed to bear a maximum load of about 1000 kg, with a counter weight of 2.6 KN which gave the crane a 3.034 factor of safety. The materials employed are; sheet metals, angular iron, bolts, nuts, metal rollers etc. The fabrication processes involved drawing, marking out, cutting, filling, welding and assembling. For permanent joints, the arc welding process was employed. As indicated earlier, the mobile floor crane gains its significance in the transportation of heavy machine parts within and outside the workshop. It can also be used to load and unload machine parts on trucks.

Queuing is an unavoidable condition faced in our day to day life. In a given organisation where service is being provided, a queue or waiting line is formed whenever an existing request of customers surpasses the present capability of servers to function. In this research, an estimation of passenger queuing time at the ticket window section of the Abuja (Idu) Railway station, Nigeria was carried out. The study design used in this research is the cross section descriptive observational study design, major data for the study was obtained by observation, using two digital stop watch to determine the number of servers, average arrival rate and average service rate of passengers with respect to the various train departure time without distracting employees of the railway station. Multi server approach with its queuing mathematical model was embedded using MS excel spreadsheet to develop a queue excel template which was used to analyse and calculate the system performance measures (the average time a passenger is expected to spend in the ticketing section Original Research Article

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Overtime, reduction in the amount of heat generated in engineering systems in operations have been of great concern and have continuously been under study. It is in line with the above that this research work developed a mathematical model of an evaporative cooling pad using sintered Nigerian clay. A physical model of the evaporative cooling phenomenon was developed followed by the derivation of the governing equations describing the energy and mass transfer for the clay model from the laws of conservation of continuum mechanics. A set of reasonable and appropriate assumptions were imposed upon the physical model. Constitutive relationships were also developed for further analysis of the developed equations. The finite element model of numerical methods was used to analyse the energy transfer governing equations which resulted in the determination of the temperature of the exposed boundary surface at any given time, t 2 after the commencement of the evaporative cooling processes. In this paper, it was found out that surface temperature differences could be as much as 6˚C in the first cycle of evaporative cooling with the potential of further reduction. Further, an equation for the prediction of the effectiveness of an evaporative cooling system using clay modeled cooling pads was developed. The findings in this research work can be applied in the design, construction and maintenance of evaporative coolers used to dissipate waste heat when a large amount of natural water is not readily available or if for environmental and safety reasons the large water body can no longer absorb waste heat.

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