Novel ester compounds and the use of these esters as a fragrance chemicals, suitable for use in creating fragrance, and scents in items such as perfumes, colognes and personal care products are disclosed. The idle temperature setpoint and the driving temperature setpoint are derived individually of and separately from each other, and are based on different criteria. The control unit includes a phase detection device to detect whether a phase of the AC voltage is positive or negative, and to output a detection signal that is based on whether the phase is positive or negative, and a logic unit to generate the switch control signal based on load control signals and the detection signal. When performance of the streaming application indicates a virtual machine is no longer needed, the virtual machine is maintained and placed in a ready state so it can be quickly used as needed in the future without the overhead of deploying a new virtual machine. However, since the USB power and wall adapter power are current limited, if the load requires higher current than the current limited USB or adapter, then the entire system is powered at voltage of the battery.