Abstract: The present disclosure relates to an organic electroluminescent compound and an organic electroluminescent device comprising the same. By comprising the compound according to the present disclosure, it is possible to produce an organic electroluminescent device having improved driving voltage, power efficiency, and/or lifetime properties compared to the conventional organic electroluminescent devices.

Abstract: The present invention relates to a multi-component host material and an organic electroluminescent device comprising the same. By comprising a specific combination of the multi-component host compounds, the organic electroluminescent device according to the present invention can provide high luminous efficiency and excellent lifespan characteristics.

Abstract: Provided is a thermoelectric cooling device comprising: a thermoelectric module; a heat sink having a body, which has on one side a contact surface coming into contact with a heating side of the thermoelectric module, and a plurality of heat dissipation fins, and emitting the heat transferred from the heating side of the thermoelectric module; a heat pipe coupled to a mounting groove which is formed on the contact surface of the heat sink, and for transferring heat by means of a working fluid stored therein; and a cooling fan for forming the airflow to the heat sink, wherein the heat pipe comprises a plurality of corner-extension heat pipes extending to a corner area of the heat sink from the central part of the heat sink on which the thermoelectric module is installed, and the shape of the mounting groove corresponds to the shape of the corner-extension heat pipes.

Abstract: An air purifying unit in which leakage of air flowing between a filter and a blowing fan is significantly reduced, and an air cleaning/ventilation device including the same, are provided. In addition, there are an air cleaning/ventilation device detachably installed in a window, used as a ventilation device, and used as an indoor air cleaning device.

Abstract: An air purifying unit in which leakage of air flowing between a filter and a blowing fan is significantly reduced, and an air cleaning/ventilation device including the same, are provided. In addition, there are an air cleaning/ventilation device detachably installed in a window, used as a ventilation device, and used as an indoor air cleaning device.

Abstract: A heat exchanger washing device includes a wash water storage chamber to store wash water in a case, a wash water injection chamber to jet the wash water stored in the wash water storage chamber to a heat exchanger, and a bypass path unit to guide the wash water jetted from the wash water injection chamber to a side surface of the heat exchanger after bypassing an upper surface of the heat exchanger.

Abstract: A water level sensor is closely adhered to a storage tank, and a heat exchanger sterilizing and humidifying apparatus allows the water level sensor to be mounted at the outside of the storage tank, thus having a simple configuration. The water level sensor may include a holder, a cap connected to the holder so as to reciprocate within the holder, a case connected to the cap so as to reciprocate within the holder, a sensor part attached to the case to sense the water level in the storage tank, and a spring located between the holder and the cap, wherein the sensor part mounted at the outside of the storage tank and attached to the case by restoring force of the spring when the storage tank contacts the case may be closely adhered to the storage tank and thus may sense a level of water stored in the storage tank.

Abstract: A water level sensor is closely adhered to a storage tank, and a heat exchanger sterilizing and humidifying apparatus allows the water level sensor to be mounted at the outside of the storage tank, thus having a simple configuration. The water level sensor may include a holder, a cap connected to the holder so as to reciprocate within the holder, a case connected to the cap so as to reciprocate within the holder, a sensor part attached to the case to sense the water level in the storage tank, and a spring located between the holder and the cap, wherein the sensor part mounted at the outside of the storage tank and attached to the case by restoring force of the spring when the storage tank contacts the case may be closely adhered to the storage tank and thus may sense a level of water stored in the storage tank.

Abstract: A water level sensor is closely adhered to a storage tank, and a heat exchanger sterilizing and humidifying apparatus allows the water level sensor to be mounted at the outside of the storage tank, thus having a simple configuration. The water level sensor may include a holder, a cap connected to the holder so as to reciprocate within the holder, a case connected to the cap so as to reciprocate within the holder, a sensor part attached to the case to sense the water level in the storage tank, and a spring located between the holder and the cap, wherein the sensor part mounted at the outside of the storage tank and attached to the case by restoring force of the spring when the storage tank contacts the case may be closely adhered to the storage tank and thus may sense a level of water stored in the storage tank.

Abstract: A heat exchanger washing device includes a wash water storage chamber to store wash water in a case, a wash water injection chamber to jet the wash water stored in the wash water storage chamber to a heat exchanger, and a bypass path unit to guide the wash water jetted from the wash water injection chamber to a side surface of the heat exchanger after bypassing an upper surface of the heat exchanger.

Abstract: A water level sensor is closely adhered to a storage tank, and a heat exchanger sterilizing and humidifying apparatus allows the water level sensor to be mounted at the outside of the storage tank, thus having a simple configuration. The water level sensor may include a holder, a cap connected to the holder so as to reciprocate within the holder, a case connected to the cap so as to reciprocate within the holder, a sensor part attached to the case to sense the water level in the storage tank, and a spring located between the holder and the cap, wherein the sensor part mounted at the outside of the storage tank and attached to the case by restoring force of the spring when the storage tank contacts the case may be closely adhered to the storage tank and thus may sense a level of water stored in the storage tank.

Abstract: A method for fabricating a semiconductor device includes forming a hard mask pattern over a substrate, forming a protection layer by transforming a portion of a sidewall of the hard mask pattern, forming a trench by etching the substrate using the hard mask pattern and the protection layer as an etch barrier, forming an isolation layer by filling the trench with an insulation material, removing the hard mask pattern, and performing a cleaning process. By forming the protection layer, it is possible to prevent the isolation layer from being lost during the removing of the hard mask pattern and the cleaning process and thus prevent generation of a moat.

Abstract: A method for fabricating a semiconductor device includes forming a hard mask pattern over a substrate, forming a protection layer by transforming a portion of a sidewall of the hard mask pattern, forming a trench by etching the substrate using the hard mask pattern and the protection layer as an etch barrier, forming an isolation layer by filling the trench with an insulation material, removing the hard mask pattern, and performing a cleaning process. By forming the protection layer, it is possible to prevent the isolation layer from being lost during the removing of the hard mask pattern and the cleaning process and thus prevent generation of a moat.