Abstract: An input apparatus of a mobile terminal and its display method are disclosed. The input apparatus of the mobile terminal according to an embodiment includes a keypad having a plurality of keys and generating key signals corresponding to a selection of the keys; a plurality of light emitting elements positioned at the plurality of keys, respectively, for illuminating the keys; a key sensor for sensing the key signals from the keypad; a storage unit for storing the key signals; and a controller for displaying, on the keypad, information corresponding to the key signals by selectively controlling the plurality of light emitting elements based on the key signals.

Abstract: An input apparatus of a mobile terminal and its display method are disclosed. The input apparatus of the mobile terminal according to an embodiment includes a keypad having a plurality of keys and generating key signals corresponding to a selection of the keys; a plurality of light emitting elements positioned at the plurality of keys, respectively, for illuminating the keys; a key sensor for sensing the key signals from the keypad; a storage unit for storing the key signals; and a controller for displaying, on the keypad, information corresponding to the key signals by selectively controlling the plurality of light emitting elements based on the key signals.

Abstract: Disclosed is a multi-density polyester fiber panel, which includes a polyester binder fiber, containing low melting point polyester with a melting point of 100° C. to 160° C., and a high melting point polyester matrix fiber. The multi-density polyester fiber panel includes an interior part, and surface parts layered on both sides of the interior part. At this time, each of the surface parts contains polyester matrix fiber having 2 to 4 times larger monofilament fineness than polyester matrix fiber contained in the interior part, and has a different density from the interior part. Therefore, the multi-density polyester fiber panel, which has a noise-absorbing ability improved by about 20% or more without the reduction of bending strength, in comparison with a conventional polyester fiber panel, can be efficiently used as a substitute of a glass wool panel with relatively high strength and density.

Abstract: Disclosed is a method of producing a polyester fire-retardant core matrix for a prefabricated panel. The method includes adding a fire-retardant agent to a polyester floss to allow the fire-retardant agent to permeate into the polyester floss, rolling the polyester floss, drenched by the fire-retardant agent, using a roller to promote permeation of the fire-retardant agent into the polyester floss, drawing the excess fire-retardant agent from the polyester floss using a perforated roller, of which an air suction force is easily controlled, drying the semi-dried polyester floss using a microwave generating unit, and foaming the dried polyester floss using a heater. The polyester fire-retardant core matrix has advantages of excellent fire-retardancy, high strength, and low absorptivity.

Abstract: Disclosed is a polyester flame-retardant core for prefabricated panels, which is remarkably improved in compression strength and bending strength through a foaming process of a flame-retardant material treated to polyester floss. Further, a method of manufacturing the polyester flame-retardant core, including treating polyester floss with a foamable flame-retardant material to allow the foamable flame-retardant material to be stuck between fibers of the polyester floss, followed by drying, and foaming the foamable flame-retardant material stuck between the fibers of the polyester floss by heating. The thus obtained flame-retardant core can exhibit superior compression strength and bending strength, even with a low density. Hence, the flame-retardant core can be economically manufactured and easily handled and constructed, and can improve in heat-insulating properties or weather resistance, on account of foaming properties thereof.