Abstract: The polycarbonate copolymer of the present invention comprises: a unit derived from at least one type of primary dihydroxyl compound; and a unit derived from at least two types of secondary dihydroxyl compounds, wherein the polycarbonate copolymer has a pencil hardness of H or greater, when a specimen is measured according to the pencil hardness test (ISO 15184), and a glass transition temperature (Tg) of about 90° C. to about 160° C., measured according to ISO 11357. The polycarbonate copolymer has excellent heat resistance, scratch resistance, moldability, light resistance, weather resistance, transparency, mechanical strength, and the like.

Abstract: An apparatus for detecting a mark by using image matching includes a damaged content obtaining unit configured to obtain damaged content generated based on original content including a plurality of cuts; a pre-processed content generating unit configured to generate pre-processed content by merging one or more images included in the damaged content or removing a partial region of one or more cuts included in the damaged content; a matchable content generating unit configured to generate matchable content, in which sizes or locations of one or more cuts included in the pre-processed content are adjusted by comparing one or more cuts included in the original image and the one or more cuts included in the pre-processed content; a matching unit configured to compare the original content with the matchable content, for each cut.

Abstract: Provided are a method for producing a polyamide including an amide-based molecular weight controller and a polyamide produced thereby, wherein the amide-based molecular weight controller may easily control the molecular weight of the polyamide to have a narrow molecular weight distribution so as to prevent an increase in the molecular weight due to a basic intermediate produced in anionic polymerization and a side reaction generated under a high-temperature polymerization condition.

Abstract: The polycarbonate copolymer of the present invention comprises: a unit derived from at least one type of primary dihydroxyl compound; and a unit derived from at least two types of secondary dihydroxyl compounds, wherein the polycarbonate copolymer has a pencil hardness of H or greater, when a specimen is measured according to the pencil hardness test (ISO 15184), and a glass transition temperature (Tg) of about 90° C. to about 160° C., measured according to ISO 11357. The polycarbonate copolymer has excellent heat resistance, scratch resistance, moldability, light resistance, weather resistance, transparency, mechanical strength, and the like.

Abstract: The present invention provides a method for producing a polyamide with controlled activator addition, and a polyamide produced thereby, the method allowing a polymerization conversion rate and a polydispersity index (PDI) to be enhanced by controlling the addition of an activator so as to prevent a gelation phenomenon that occurs during anionic polymerization.

Abstract: Provided is an apparatus for preventing a content leak, including: a view request receiving unit for receiving a content view request for view target content to obtain content viewer information; a marker form determining unit for determining a marker form regarding a location of the view target content where a marker for each character is added, according to the content viewer information; a marking method determining unit for determining a marking method regarding a type or order of markers added to the marker form; and a modified content generating unit for generating modified content by adding, to the view target content, one or more markers corresponding to the content viewer information, based on the marker form and the marking method.

Abstract: The present invention relates to a method for producing a polyamide by coordinated anionic ring-opening polymerization and a polyamide produced thereby, wherein metal alkoxide as an initiator and metal hydride as a catalyst are added to enable polymerization having a narrow molecular weight distribution and uniform molecular weight within a short polymerization reaction time at a low temperature, without a separate vacuum process, as compared with an existing polymerization method.

Abstract: The present invention relates to a lightweight sandwich steel sheet using polyamide, and more particularly, to a lightweight sandwich steel sheet using polyamide and a manufacturing method therefor, the steel sheet being usable at a wider temperature range than that of a conventional sandwich steel sheet and, particularly, having excellent adhesion at a low temperature and remarkably increasing stability and lightweight property.

Abstract: The present invention relates to a method for preparing a polyamide by anionic ring-opening copolymerization in consideration of the reactivity between a monomer and an alkali metal-based initiator. The present invention relates to a method for preparing a polyamide by anionic ring-opening copolymerization and a polyamide prepared thereby, in which, by adding a metal hydride, which is an alkali metal-based initiator, to a lactam having higher reactivity therewith, a production rate of an anion-initiated monomer is increased, thus enabling polymerization with a high conversion rate within a short polymerization reaction time to obtain a polymer having a uniform molecular weight. In the method for preparing the polyamide by anionic ring-opening copolymerization (AROP), a metal hydride is added as an alkali metal-based initiator in an amount of 0.

Abstract: Disclosed is a method for authenticating a management entity by an aid entity to maintain human rights of a management object when the management entity applies to the aid entity a help of a protective management action for the management object which is difficult or impossible to do an independent living by himself/herself, the method comprising: an authentication module preparation step of registering original biometric information acquired from a biometric sensor in an authentication module of the management entity registered in an authentication server; a help application step of transmitting help application information of a protective management action for the management object to a reception server of the aid entity from a management terminal of the management entity; a biometric information input step of acquiring instantaneous biometric information from the biometric sensor and inputting the acquired instantaneous biometric information to the authentication module; a module determination processing s

Abstract: Provided is an apparatus for preventing a content leak, including: a view request receiving unit for receiving a content view request for view target content to obtain content viewer information; a marker form determining unit for determining a marker form regarding a location of the view target content where a marker for each character is added, according to the content viewer information; a marking method determining unit for determining a marking method regarding a type or order of markers added to the marker form; and a modified content generating unit for generating modified content by adding, to the view target content, one or more markers corresponding to the content viewer information, based on the marker form and the marking method.

Abstract: An apparatus for detecting a mark by using image matching includes a damaged content obtaining unit configured to obtain damaged content generated based on original content including a plurality of cuts; a pre-processed content generating unit configured to generate pre-processed content by merging one or more images included in the damaged content or removing a partial region of one or more cuts included in the damaged content; a matchable content generating unit configured to generate matchable content, in which sizes or locations of one or more cuts included in the pre-processed content are adjusted by comparing one or more cuts included in the original image and the one or more cuts included in the pre-processed content; a matching unit configured to compare the original content with the matchable content, for each cut.

Abstract: Provided are a method for preparing a polyamide by using a molecular weight controller having a double active group in anionic ring-opening copolymerization of a polyamide, thereby enabling molecular weight to be controlled through the addition reaction of the molecular weight controller, and a polyamide prepared thereby.

Abstract: Provided are a method for producing a polyamide including an amide-based molecular weight controller and a polyamide produced thereby, wherein the amide-based molecular weight controller may easily control the molecular weight of the polyamide to have a narrow molecular weight distribution so as to prevent an increase in the molecular weight due to a basic intermediate produced in anionic polymerization and a side reaction generated under a high-temperature polymerization condition.

Abstract: The present invention relates to a lightweight sandwich steel sheet using polyamide, and more particularly, to a lightweight sandwich steel sheet using polyamide and a manufacturing method therefor, the steel sheet being usable at a wider temperature range than that of a conventional sandwich steel sheet and, particularly, having excellent adhesion at a low temperature and remarkably increasing stability and lightweight property.

Abstract: Provided are a method for producing a polyamide using an end-capping agent and a polyamide produced thereby, wherein the method is an eco-friendly process method without using a solvent as a catalyst and may prepare, by using an end-capping agent for suppressing side reaction, a polymer having a uniform molecular weight and a high conversion rate at a low temperature within a short polymerization time in comparison with a conventional polymerization method.

Abstract: The present invention relates to an electronic approval method using biometric authentication, comprising: a biometric certificate storage step in which biometric certificates issued, encrypted and hashed by a biometric authentication server are stored and activated in biometric recognition modules of a manager and approvers; an approver list registration step in which the manager logs in to an approval server and then an approver list is registered in the approval server; an approver's approval step in which for the approval of each of the approvers to the approval server, biometric information of the approvers is input into the biometric recognition modules, the biometric certificate is transmitted to the biometric authentication server accordingly, the biometric certificate is hashed to be verified whether original or not and is decrypted to be verified by the content, and then a biometric authentication result is transmitted to the approval server; an approver's approval server log-in step in which for th

Abstract: The present invention relates to a method for producing a polyamide by coordinated anionic ring-opening polymerization and a polyamide produced thereby, wherein metal alkoxide as an initiator and metal hydride as a catalyst are added to enable polymerization having a narrow molecular weight distribution and uniform molecular weight within a short polymerization reaction time at a low temperature, without a separate vacuum process, as compared with an existing polymerization method.

Abstract: The present invention provides a method for producing a polyamide with controlled activator addition, and a polyamide produced thereby, the method allowing a polymerization conversion rate and a polydispersity index (PDI) to be enhanced by controlling the addition of an activator so as to prevent a gelation phenomenon that occurs during anionic polymerization.

Abstract: Provided is a method for preparing a polyamide by an anionic polymerization reaction, wherein lactam, and based on 100 parts by weight of the entire lactam, 0.01 parts by weight to 20 parts by weight of an alkali metal as an initiator, 0.3 parts by weight to 10 parts by weight of a molecular weight controller, and 0.002 parts by weight to 1.0 part by weight of carbon dioxide as an activator may be included.