Abstract: Disclosed is a method of monitoring a problem related to a railroad car by a railroad car monitoring apparatus, the method including: selecting a monitoring target of the railroad car; selecting a diagnosis reference related to the monitoring target; measuring travelling data related to the monitoring target while the railroad car travels; drawing a result value of the characteristic function according to the travelling data and comparing each of the travelling data with a reference value in a normal state and determining whether a defect is generated in the monitoring target.

Abstract: Disclosed is a method of monitoring a problem related to a railroad car by a railroad car monitoring apparatus, the method including: selecting a monitoring target of the railroad car; selecting a diagnosis reference related to the monitoring target; measuring travelling data related to the monitoring target while the railroad car travels; drawing a result value of the characteristic function according to the travelling data and comparing each of the travelling data with a reference value in a normal state and determining whether a defect is generated in the monitoring target.

Abstract: An apparatus for controlling a refrigerant level comprises a first detecting unit installed at a lower side of the inside of a refrigerant tank, for detecting whether a refrigerant stored at a lower side of the inside of the refrigerant is a liquefied refrigerant or a gaseous refrigerant, a second detecting unit installed at an upper side of the inside of the refrigerant tank, for detecting whether a refrigerant stored at an upper side of the inside of the refrigerant tank is a liquefied refrigerant and a gaseous refrigerant, and a control unit controlling intake and discharge of the liquefied refrigerant according to a value measured by the first detecting unit and the second detecting unit.

Abstract: A supply system for supplying a functional water to a process unit which treats a substrate using the functional water is provided. In the system, the functional water generated in the functional water generator is supplied to a distributor through a functional water supply pipe. Thereafter, the functional water is supplied to the process unit while the process unit performs a process, and the functional water is returned to the functional water generator through a functional water returning pipe while the process unit does not perform a process. A buffer tank is installed in the functional water supply pipe and the concentration of the functional water is measured in a circulation line connected with the buffer tank. When the measured concentration of the functional water goes out of a set concentration range, the functional water is returned to the functional water generator through functional water returning pipe.

Abstract: A second-refrigerant pump driving type air conditioner, including an indoor unit having an indoor heat exchanger that circulates a refrigerant containing no oil, a first circulator including a compressor that compresses and discharges a refrigerant containing oil, a first outdoor heat exchanger, a second outdoor heat exchanger, and an outdoor expander, and a second circulator including an intermediate heat exchanger connected to the indoor heat exchanger that circulates the refrigerant containing no oil and heat-exchanges the refrigerant of the first outdoor heat exchanger, a receiver, and a pump. A restriction of a length and a diameter of a connection pipe for connecting an outdoor unit and the indoor unit is decreased, and an oil shortage of the compressor is prevented.

Abstract: An air conditioning system comprises a first tank connected to an outlet side refrigerant line of an indoor unit, a second tank disposed to be lower than the first tank, middle tank installed between the first tank and the second tank, a heat source cycle for depressurizing and cooling the first refrigerant inside the first tank by circulating a second refrigerant and heating the first refrigerant of the second tank, a middle tank cooling unit for feed back connected to an inlet side refrigerant line of the second tank among refrigerant lines of the heat source cycle, a middle tank heating unit for feed back connected to a refrigerant line between the first tank and the second tank among refrigerant lines of the heat source cycle, and a controller for selectively circulating the second refrigerant of the heat source cycle to the middle tank cooling unit for feed back or the middle tank heating unit for feed back.

Abstract: A supply system for supplying a functional water to a process unit which treats a substrate using the functional water is provided. In the system, the functional water generated in the functional water generator is supplied to a distributor through a functional water supply pipe. Thereafter, the functional water is supplied to the process unit while the process unit performs a process, and the functional water is returned to the functional water generator through a functional water returning pipe while the process unit does not perform a process. A buffer tank is installed in the functional water supply pipe and the concentration of the functional water is measured in a circulation line connected with the buffer tank. When the measured concentration of the functional water goes out of a set concentration range, the functional water is returned to the functional water generator through functional water returning pipe.

Abstract: A second-refrigerant pump driving type air conditioner, including an indoor unit having an indoor heat exchanger that circulates a refrigerant containing no oil, a first circulator including a compressor that compresses and discharges a refrigerant containing oil, a first outdoor heat exchanger, a second outdoor heat exchanger, and an outdoor expander, and a second circulator including an intermediate heat exchanger connected to the indoor heat exchanger that circulates the refrigerant containing no oil and heat-exchanges the refrigerant of the first outdoor heat exchanger, a receiver, and a pump. A restriction of a length and a diameter of a connection pipe for connecting an outdoor unit and the indoor unit is decreased, and an oil shortage of the compressor is prevented.

Abstract: An air conditioning system comprises a first tank connected to an outlet side refrigerant line of an indoor unit, a second tank disposed to be lower than the first tank, middle tank installed between the first tank and the second tank, a heat source cycle for depressurizing and cooling the first refrigerant inside the first tank by circulating a second refrigerant and heating the first refrigerant of the second tank, a middle tank cooling unit for feed back connected to an inlet side refrigerant line of the second tank among refrigerant lines of the heat source cycle, a middle tank heating unit for feed back connected to a refrigerant line between the first tank and the second tank among refrigerant lines of the heat source cycle, and a controller for selectively circulating the second refrigerant of the heat source cycle to the middle tank cooling unit for feed back or the middle tank heating unit for feed back.

Abstract: An air conditioning system comprises an indoor unit in which a first refrigerant flows, a first tank connected to an outlet side refrigerant line of the indoor unit for sucking a first refrigerant, a second tank connected to an inlet side refrigerant line of the indoor unit and directly connected to the first tank at a position lower than the first tank for feeding back the first refrigerant stored in the first tank to the indoor unit, a connection line disposed between the first tank and the second tank, a pressure equalizing line disposed between the first tank and the second tank, a heat source cycle for cooling the first refrigerant inside the first tank by circulating a second refrigerant and heating the first refrigerant of the second tank, and a controller for controlling a plurality of switching valves installed at the connection line and the pressure equalizing line.

Abstract: Disclosed is an air conditioner. The air conditioner includes: at least one indoor unit; an outdoor unit communicating with the indoor unit and having at least one compressor and one outdoor heat exchanger; a fluid path opening/closing valve for opening or closing a fluid path through which a refrigerant can flow to the outdoor heat exchanger; and a control unit for controlling the compressor and the fluid path opening/closing valve to perform appropriate compression and condensation of the refrigerant according to the load amount of the indoor unit. Accordingly, as the air conditioner comprises the fluid path opening/closing valve and the branch fluid path opening/closing valve which are capable of opening or closing fluid paths and a control unit for controlling the valves, a high pressure of a cycle is appropriately maintained even during small-load operation and therefore reliability in operation can be increased.

Abstract: An apparatus for controlling a refrigerant level comprises a first detecting unit installed at a lower side of the inside of a refrigerant tank, for detecting whether a refrigerant stored at a lower side of the inside of the refrigerant is a liquefied refrigerant or a gaseous refrigerant, a second detecting unit installed at an upper side of the inside of the refrigerant tank, for detecting whether a refrigerant stored at an upper side of the inside of the refrigerant tank is a liquefied refrigerant and a gaseous refrigerant, and a control unit controlling intake and discharge of the liquefied refrigerant according to a value measured by the first detecting unit and the second detecting unit.