Abstract: The present disclosure relates to a novel citrate synthase variant, a microorganism comprising the variant, and a method for producing O-acetyl-L-homoserine and L-methionine using the microorganism.

Abstract: The present disclosure is directed to providing a toothed conveyor belt type oil recovery device including: a recovery conveyor which is rotates in such a way that a continuous track rotates, the recovery conveyor having multiple teeth made of a hydrophilic material on an outer surface, the recovery conveyor having one side positioned in water in which oil is spilled to recover the oil while feeding the oil into a space between the adjacent teeth by the rotation; and a separation unit which holds an oil separating liquid, and is positioned on the other side of the recovery conveyor to separate the oil from the teeth while the oil separating liquid is fed into the space between the adjacent teeth by capillary suction when the teeth move on to the oil separating liquid on the other side of the recovery conveyor by the rotation of the recovery conveyor.

Abstract: The present disclosure is directed to providing an oil-water separation filter structure including a base guide having a separated water outlet hole through which a fluid separated from a mixed fluid including an impurity exits, an oil-water separation filter disposed on the base guide to separate the impurity and the fluid included in the mixed liquid, and a top guide disposed on the oil-water separation filter, having at least one mixed fluid inlet hole through which the mixed fluid enters, and coupled to the base guide. According to the present disclosure, the oil-water separation filter structure includes a hydrophilic material to separate water and oil, and as opposed to the existing nonwoven fabric type filters, can be continuously used, thereby preventing environmental pollution problems.

Abstract: Provided is a toothed drum type oil recovery device, which includes: a recovery drum having a center coupled to a rotary shaft and having a plurality of tooth units formed around an outer circumference thereof, wherein one side of the recovery drum is disposed in the water to which oil is spilled so that the oil is recovered by the tooth unit at one side of the recovery drum according to the rotation; and a separation unit containing an oil separating liquid and disposed at the other side of the recovery drum, wherein when the tooth unit moves onto the oil separating liquid at the other side of the recovery drum according to the rotation of the recovery drum, the oil separating liquid is introduced into a space between the tooth units adjacent to each other by means of a capillary action to separate the oil from the tooth unit.

Abstract: The present disclosure is directed to providing impeller type oil transportation device including; a transport unit provided such that a mixed fluid including an oil is fed on one side; and an impeller provided in the transport unit, the impeller including a core connected to a rotation axis, and wings extending radially from the core and having hydrophilic teeth on an outer surface to transport the mixed fluid including the oil to the other side of the transport unit by rotation, wherein the impeller is provided in the transport unit such that parts of the wings are exposed above a surface of the mixed fluid, to separate the oil adhered to the teeth while the mixed fluid is fed into a space between the adjacent teeth by capillary flow when the wings exposed above the surface of the mixed fluid move on to the mixed fluid by the rotation.

Abstract: Disclosed is a method, system, and non-transitory computer-readable record medium for protecting content copyright in a chatroom. A content protection method includes adding, by at least one processor, a mark to content in a chatroom, the mark including chatroom information for identifying the chatroom in response to a user request from a user associated with the content in the chatroom, and executing, by the at least one processor, a function corresponding to the user request using the content to which the mark is added.

Abstract: Provided are a method, a system, and a non-transitory computer readable record medium for controlling joining a chatroom based on a location. The method may include identifying a first location of an electronic device at a first point in time; displaying a chatroom that uses a user location as a chatroom joining condition, and that allows a user of an electronic device to join based on the first location of the electronic device; and in response to a join request being input at a second point in time from the user to join the displayed chatroom, determining whether to allow the user to join the chatroom based on a second location of the electronic device at the second point in time at which the join request is input.

Abstract: The present disclosure is directed to providing impeller type oil transportation device including; a transport unit provided such that a mixed fluid including an oil is fed on one side; and an impeller provided in the transport unit, the impeller including a core connected to a rotation axis, and wings extending radially from the core and having hydrophilic teeth on an outer surface to transport the mixed fluid including the oil to the other side of the transport unit by rotation, wherein the impeller is provided in the transport unit such that parts of the wings are exposed above a surface of the mixed fluid, to separate the oil adhered to the teeth while the mixed fluid is fed into a space between the adjacent teeth by capillary flow when the wings exposed above the surface of the mixed fluid move on to the mixed fluid by the rotation.

Abstract: The present disclosure is directed to providing a toothed conveyor belt type oil recovery device including: a recovery conveyor which is rotates in such a way that a continuous track rotates, the recovery conveyor having multiple teeth made of a hydrophilic material on an outer surface, the recovery conveyor having one side positioned in water in which oil is spilled to recover the oil while feeding the oil into a space between the adjacent teeth by the rotation; and a separation unit which holds an oil separating liquid, and is positioned on the other side of the recovery conveyor to separate the oil from the teeth while the oil separating liquid is fed into the space between the adjacent teeth by capillary suction when the teeth move on to the oil separating liquid on the other side of the recovery conveyor by the rotation of the recovery conveyor.

Abstract: Methods, computer devices, and non-transitory computer-readable record media for displaying a message thread on a chatroom cover screen may be provided. A chatroom cover display method may include receiving a message thread including messages exchanged through a chatroom in response to an access request for the chatroom, and displaying a cover screen of the chatroom in response to the access request and displaying the message thread on the cover screen.

Abstract: Provided is a method and system for providing an answer message to a query message. An answer message providing method may include managing a plurality of chatrooms of an instant messaging service; receiving a query message in a preset form from a first user of a first chatroom among the plurality of chatrooms; forwarding the query message to second users through the instant messaging service; receiving an answer message to the query message from at least one of the second users; and providing the received answer message to be displayed through the first chatroom.

Abstract: Disclosed is a method, system, and non-transitory computer-readable record medium for creating a chatroom according to a condition. The chatroom creation method may include providing an instant messaging service; registering a chatroom creation condition related to a specific account of the instant messaging service; retrieving at least one account of accounts of the instant messaging service that meets the chatroom creation condition; and automatically creating a chatroom of the specific account joined by the retrieved accounts.

Abstract: Provided is a toothed drum type oil recovery device, which includes: a recovery drum having a center coupled to a rotary shaft and having a plurality of tooth units formed around an outer circumference thereof, wherein one side of the recovery drum is disposed in the water to which oil is spilled so that the oil is recovered by the tooth unit at one side of the recovery drum according to the rotation; and a separation unit containing an oil separating liquid and disposed at the other side of the recovery drum, wherein when the tooth unit moves onto the oil separating liquid at the other side of the recovery drum according to the rotation of the recovery drum, the oil separating liquid is introduced into a space between the tooth units adjacent to each other by means of a capillary action to separate the oil from the tooth unit.

Abstract: Provided is a method and system for providing an answer message to a query message. An answer message providing method may include managing a plurality of chatrooms of an instant messaging service; receiving a query message in a preset form from a first user of a first chatroom among the plurality of chatrooms; forwarding the query message to second users through the instant messaging service; receiving an answer message to the query message from at least one of the second users; and providing the received answer message to be displayed through the first chatroom.

Abstract: Disclosed is a method, system, and non-transitory computer-readable record medium for creating a chatroom according to a condition. The chatroom creation method may include providing an instant messaging service; registering a chatroom creation condition related to a specific account of the instant messaging service; retrieving at least one account of accounts of the instant messaging service that meets the chatroom creation condition; and automatically creating a chatroom of the specific account joined by the retrieved accounts.

Abstract: Disclosed is a method, system, and non-transitory computer-readable record medium for protecting content copyright in a chatroom. A content protection method includes adding, by at least one processor, a mark to content in a chatroom, the mark including chatroom information for identifying the chatroom in response to a user request from a user associated with the content in the chatroom, and executing, by the at least one processor, a function corresponding to the user request using the content to which the mark is added.

Abstract: Disclosed is a method, system, and non-transitory computer-readable record medium for protecting content copyright in a chatroom. A content protection method includes adding, by at least one processor, a mark to content in a chatroom, the mark including chatroom information for identifying the chatroom in response to a user request from a user associated with the content in the chatroom, and executing, by the at least one processor, a function corresponding to the user request using the content to which the mark is added.

Abstract: The present disclosure is directed to providing an oil-water separation filter structure including a base guide having a separated water outlet hole through which a fluid separated from a mixed fluid including an impurity exits, an oil-water separation filter disposed on the base guide to separate the impurity and the fluid included in the mixed liquid, and a top guide disposed on the oil-water separation filter, having at least one mixed fluid inlet hole through which the mixed fluid enters, and coupled to the base guide. According to the present disclosure, the oil-water separation filter structure includes a hydrophilic material to separate water and oil, and as opposed to the existing nonwoven fabric type filters, can be continuously used, thereby preventing environmental pollution problems.

Abstract: Disclosed is a hydrophilic material oil fence having a double-porous mesh. The hydrophilic material oil fence having the double-porous mesh includes a floating body floating on a water surface, and a skirt coupled to an upper portion and a lower portion of the floating body and made of a hydrophilic material through which a hydrophilic fluid selectively passes. A mesh hole size of a partial region of the skirt and a mesh hole size of the other region of the skirt are different.

Abstract: Provided is a method and system for providing an answer message to a query message. An answer message providing method may include managing a plurality of chatrooms of an instant messaging service; receiving a query message in a preset form from a first user of a first chatroom among the plurality of chatrooms; forwarding the query message to second users through the instant messaging service; receiving an answer message to the query message from at least one of the second users; and providing the received answer message to be displayed through the first chatroom.