Abstract: A filter holder comprises: a plurality of filter frames disposed such that at least some thereof are adjacent to each other; and a folding member which supports filter frames, from among the plurality of filter frames, adjacent to each other so as to be rotatable with respect to each other. The folding member comprises: a folding part which has a predetermined thickness and is flexible so as to be foldable by means of rotation of the adjacent filter frames adjacent with respect to each other; and a plurality of edge parts which are connected to the respective sides of the folding part with the folding portion therebetween and rotate together with the adjacent filter frames, and wherein when viewed from a cross-section of the folding member, the edge parts may have a greater thickness than the folding part.

Abstract: The present invention relates to a method and system for providing language learning services. The method of providing language learning services, according to the present invention, the method may include: activating, in response to receiving an input for acquiring a learning target image through a user terminal, a camera of the user terminal; specifying at least a portion of an image taken by the camera as the learning target image; receiving language learning information for the learning target image from a server; providing the language learning information to the user terminal; and storing, based on a request for storing of the language learning information, the language learning information in association with the learning target image, such that the learning target image is used in conjunction with learning of the language learning information.

Abstract: An air filter comprises: a first filter frame in which a plurality of first chambers are formed; a second filter frame in which a plurality of second chambers are formed and which is arranged at the rear of the first filter frame; and a filter material which is accommodated in the plurality of first chambers and the plurality of second chambers to filter air, wherein the first filter frame and the second filter frame are arranged so that, when seen from the front, the center of each of the plurality of second chambers is out of line with the center of each of the plurality of first chambers, in the vertical direction.

Abstract: An apparatus and method for providing a multicast/broadcast service in a mobile communication system. Upon detecting an occurrence of a multicast data packet, an Internet Protocol (IP) terminal converts the multicast data packet into an alternative multicast data packet, and transmits the alternative multicast data packet to a femto Node B. Upon detecting an occurrence of a broadcast data packet, the IP terminal converts the broadcast data packet into an alternative broadcast data packet, and transmits the alternative broadcast data packet to the femto Node B.