An aspect of the invention is an information terminal device includes a widget management unit for managing execution of a widget being a monofunctional program for performing display on the display part of a display device. A method of controlling a variable inlet guide vane arrangement for a compressor includes pivoting at least some of the plurality of vanes in an asymmetrical pattern around the circumference of the case. Alternatively, the flexible zipper is joined to the front wall along first and second zones of joinder disposed at different heights on the front wall, and is joined to the rear wall only in zones of joinder where the zipper is joined to both of the front and rear walls. The management device includes a management engine that is configured to retrieve management information from any of the plurality of managed devices through the backplane and display the management information that was retrieved on the display. Hence, strength of the frame is reinforced, vibration and noise are reduced during a fan wheel running and integral effect of heat dissipation is enhanced largely. The apparatus is configured in such a way that light whose center axis portion is optically hollow is supplied from the reference-light-side recording and reproducing lens 6 to the recording medium 1 during reproducing operation.