The present invention utilizes a comprehensive object oriented software architecture that is flexibly extendible to accommodate numerous features and activities associated software distribution including software development, management, marketing, selling and delivery. It includes a plurality of light source units emitting the illumination light and arranged in a direction so that a direction in which intensity of light emitted from at least one of the light source units closest to a center of the arrangement thereof is to be highest makes a non-perpendicular angle with the direction of arrangement. The interior surface of the cushion can be configured to effectively match the acoustical impedance at the output face of the speaker to the acoustical impedance at the entrance of the listener’s ear. A resistance memory bridge is in contact with an edge surface of the first and second electrodes. 0, a Qm\xd7fo value of not less than 50000 and an absolute value of a temperature coefficient \u03c4f of resonance frequency fo of not more than 30 ppm\xb0 C. A second variable characterizing the energy released during the combustion is ascertained from the first variable.