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Hybrid electric vehicles (HEVs) are considered as the most commercial prospects new energy vehicles. Most HEVs have adopted Atkinson cycle engine as the main drive power. Atkinson cycle engine uses late intake valve closing (LIVC) to reduce pumping losses and compression work in part load operation. It can transform more heat energy to mechanical energy, improve engine thermal efficiency and decrease fuel consumption. In this paper, the investigations of Atkinson cycle converted from conventional Otto cycle gasoline engine have been carried out. First of all, high geometry compression ratio (CR) has been optimized through piston redesign from 10.5 to 13 in order to overcome the intrinsic drawback of Atkinson cycle in that combustion performance deteriorates due to the decline in the effective CR. Then, both intake and exhaust cam profile have been redesigned to meet the requirements of Atkinson cycle engine.

A current trend by automotive manufacturers involves using tires with a lower aspect ratio, while increasing the rim diameter to effectively maintain the same final drive ratio. The use of larger 16- and 17-inch rims in the design of automobiles is dramatically increasing, especially from American and European automotive manufacturers. This trend is responsible for increased vehicle life cycle costs, increased vehicle fuel consumption and increasing waste and consumption of precious resources, all while reducing commonly monitored sustainable fleet deliverables. A measurable burden for a fleet based organization is the additional cost associated with purchasing lower profile tires for larger diameter rims. The use of a lower aspect ratio tire will increase the total output of waste which reduces sustainable goals. In order for a manufacturer to maintain the same final drive ratio with lower aspect ratio tires, it is necessary to use a physically larger rim.

A current trend by automotive manufacturers involves the use of Oil Life Monitoring Systems (OLMS) to determine the drain interval of the engine oil. The premise of the OLMS system is to extend the oil drain interval by monitoring engine parameters and reduce the number of oil changes during the vehicle's lifecycle. The OLMS uses an engine oil sensor or various engine sensors and an advanced algorithm to predict when the engine oil has reached the end of its lifecycle. The OLMS effectively supports customer demands for lower operating costs and government fleet requirements to reduce the consumption of petroleum derived products and hazardous waste. This research analyzed the correlation between various external influences that alter the output of the OLMS. The external influences include monitoring of the vehicle operating conditions in densely populated metropolitan statistical areas versus more rural areas.