Methods and apparatus, including computer systems and program products, for executing a query, for example, a query for a document similar to another document. The sliding-cover selectively covers an internal space of the apparatus body and forms a rotatable connection with the angle-adjustment device. Furthermore, throughput is greatly improved by the low temperature bake, particularly in combination with low temperature plasma cleaning and low temperature wafer loading prior to the bake, and deposition after the bake at temperatures lower than conventional epitaxial deposition. The thin metal film used as metal interconnects in highly integrated semiconductor circuits contributes to the progress of a process of fabricating semiconductor devices. In one embodiment, the compact representation of the child block is provided by drawing a line segment below the transaction fiber.