Database storage of hierarchically structured messages is facilitated based on structural semantic reflection of the message and automatic reconciliation of the messages. The home appliance includes a cabinet having a chamber in which an object is received or retrieved, a door to open or close the chamber, and a handle assembly to be rotated relative to the door during opening or closing of the door, wherein rotation of the handle assembly causes the door to be rotated about a door rotating axis. The common pixel cell components may be shared by a number of pixels in the array, and may include several components that are associated with the storage and readout of a signal from the pixel cells. Upon activation, the VCS server can support voice over IP communication and connect an incoming call to a telephone via PSTN or a PBX network. Toner levels of toner cartridges arranged in the developing units are detected by rotating the cylinder a predetermined angle to stop the cylinder and measuring a flow-down time of a toner, which flows down inside of the toner cartridge, using an optical sensor. A shock wave generation apparatus comprises: a shock wave focusing device which has a concave surface ; an optical fiber which is inserted into the shock wave focusing device ; a tubular catheter which guides the optical fiber; an enclosure which constitutes a space to be filled with liquid at the tip of the optical fiber ; and the liquid which is filled into the enclosure.