Abstract: The present invention relates to a sleep-inducing system using carbon dioxide. The sleep-inducing system includes a mixed gas generation unit which generates a mixed gas of which a carbon dioxide concentration is within a preset range by mixing provided carbon dioxide and air, an emission unit which sprays the mixed gas from a position spaced apart from a user's face, a concentration sensing sensor which measures the carbon dioxide concentration of the sprayed mixed gas, and a control unit which controls the carbon dioxide concentration of the mixed gas generated by the mixed gas generation unit to be within the preset range on the basis of the measured carbon dioxide concentration.

Abstract: The present invention relates to a sleep-inducing system using carbon dioxide. The sleep-inducing system includes a mixed gas generation unit which generates a mixed gas of which a carbon dioxide concentration is within a preset range by mixing provided carbon dioxide and air, an emission unit which sprays the mixed gas from a position spaced apart from a user's face, a concentration sensing sensor which measures the carbon dioxide concentration of the sprayed mixed gas, and a control unit which controls the carbon dioxide concentration of the mixed gas generated by the mixed gas generation unit to be within the preset range on the basis of the measured carbon dioxide concentration.

Abstract: Disclosed herein is an air duct structure for a vehicle. The air duct structure comprises an air conditioning unit to condition air supplied from an outside to a preset temperature and to supply the conditioned air to an interior of the vehicle through connection holes, an integral side duct assembly comprising a suction part tightly installed to the connection holes of the air conditioning unit and left and right side ducts integrally formed with left and right sides of the suction part, and a central duct tightly installed to an upper side of the suction part to supply the air to a central region of the interior of the vehicle. With this structure, the number of components constituting the air duct structure is minimized, reducing the number of fastening operations while enhancing productivity. In addition, this structure prevents air leakage between the components.