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The main advantages of electric LDT's, (Light-duty Trucks), namely: lower running and maintenance costs, zero-emissions and eco-friendly image heavily outweigh their disadvantages, specifically their higher charging time compared to ICE (internal combustion engine) vehicle refuelling and their shorter range. These advantages make electric LDTs viable because they are compatible with the driving cycles of fleet customers. Noise generated by electric LDTs is expected to be low compared to ICEs; however, the interior and exterior noise has high-frequency noise components that are usually subjectively perceived as unpleasant or annoying. The tonal components present in electric vehicles are judged as unpleasant by the vehicle's occupants, and other noise components that are usually masked by the ICE are clearly perceived, as the overall noise is lower.

The success of business jets like the Citation X, the fastest civil aircraft in use after the Concorde, highlights the need for speed to improve business and globalization. Currently, developing a supersonic business jet has many technical and economical impediments. These obstacles include sonic boom, emissions and noise requirements problems that are easily meet or do not exist for subsonic aircraft. A baseline aircraft, defined by an optimization process, is the starting point for this study. However, this baseline aircraft does not meet the sonic boom, emissions and noise requirements, which are very strict. Companion studies to this one indicate that it may be possible to meet emissions and noise requirements, but it is clear that technology infusion is necessary for the future viability of this aircraft concept to succeed.

Fatigue has been one of the main causes of failure in automotive components since the industry's beginnings. As the fatigue phenomenon is very complex and has a high degree of variability designs have traditionally been over-engineered, resulting in an increase in weight and cost. This paper investigates the predictability of the fatigue failure process in MIG welded joints due to the variability of the welding production process and the consequent uncertainty of the notch factor of the critical zone located at the transition line between the weld bead and the work piece. The study focuses on exhaust systems for cars, but the procedure and concepts presented here can be applied to any type of welded element.