A method of searching for work elements for processing in a computing system having a primary queue of work elements and at least one secondary queue of work elements. A delay circuit with a delay circuit input and a plurality of taps outputs respective, differently delayed versions of a signal from a delay circuit input. An impedance balancing circuit is provided for developing signals allowing identification of a lose electrode when the ECG system does not utilize a right leg electrode as a reference. A bottom surface is included having a number of sections which include a pivotal connection to one another and which are collapsible about the pivotal connection to an interior of the container. There is a pn junction between the bit lines and the chalcogenide glass. The second image may be produced by an electronic imager.