Abstract: A cooling system for a superconducting power apparatus including a reservoir tank for reserving a liquefied gas, a circulating pump, a heat exchanger for cooling the liquefied gas, and a circulation loop through which the liquefied gas is circulated, the superconducting power apparatus being cooled by circulating the liquefied gas in a subcooled state using the circulating pump. The cooling system further includes a pressurizing mechanism for pressurizing the liquefied gas in the reservoir tank with the same type of gas as the liquefied gas, wherein a liquid level in the reservoir tank for reserving the liquefied gas in a pressurized state is located above an outlet of a return piping of a circulating liquefied gas at least by a dissolving depth of the pressurizing gas+(plus) a liquid level movement correction amount.

Abstract: First and second switches, which are to be operated by a user, are provided on a pen-shaped housing. A first heat generating head for writing an image on a rewritable heat sensitive sheet is arranged at an end of a tapered end portion of the pen-shaped housing, and a second heat generating head, for generating heat at a temperature which is different from a temperature of heat generated from the writing head, is arranged at flat another end of the pen-shaped housing. The writing head generates heat only when the first switch is turned on, and the erasing head generates heat only when the second switch is turned on, so that the erasing head erases the image which have been written on the heat sensitive sheet from the sheet.

Abstract: A printer adapted to be optionally equipped with a sheet feeder, including a detector for detecting the installation of the sheet feeder, and a default-value setter for automatically setting a default value of a printing controller to a value for establishing a continous printing mode if the sheet feeder is installed, and for automatically setting the default value to a value for establishing a single-page printing mode if the sheet feeder is not installed. The printer further includes an operator-controlled default-value changeover device for changing the normally selected printing mode set by the default-value setter. In the continuous printing mode, cut sheets are continuously supplied one after another to the printer. In the single-page printing mode, the printing operation is stopped at the end of printing on each cut sheet.