A socket electrical connector adapted to receive a portion of a mating plug electrical connector. A plurality of connections is detected, and for each of the connections, a buffer occupancy level is determined. The list can be based upon the recency and frequency with which a user accesses items associated with the links. The sweeping switching frequency of the half bridge configured resonant inverter drives the HID lamp in a manner which effectuates arc stability and arc straightening. A wafer having a surface on which a pattern is formed which contains a pattern portion to be removed is soaked into a chemical liquid at an angle at which the surface faces downward.