摘要:
The present invention relates to a method of preparing a microcapsule with a double-layered structure which comprises the steps of performing an interfacial polymerization of an amine-aldehyde prepolymer on droplets containing an inorganic metal precursor selected from carboxylate and alkoxide compounds, and hydrolyzing the including inorganic precursors for formation of inorganic inner layer. The method of the present invention can prepare a microcapsule with a double-layered structure of an inorganic inner layer and a polymer outer layer, which is effective for eluting and substituting a core material inside the capsule.
摘要:
A home domain building method and system that allow devices to join a home domain using smart cards. In the method, a master device reads device information from a smart card having a device ID and a device key as the device information of a guest device authenticated as a legal device and transmits a challenge request signal to the guest device, the guest device randomly generates a challenge value in response to the challenge request signal, the master device encrypts the challenge value using the device key of the guest device and transmits the encrypted challenge value to the guest device, the guest device decrypts the encrypted challenge value, and if the decrypted challenge value is the same as the challenge value generated in response to the challenge request signal, the guest device allows the master device to join the guest device in the home domain.
摘要:
A method of packaging broadcast contents are provided. The method includes: extracting a copy control bit from input broadcast contents and determining whether the broadcast contents will be stored after being encrypted based on the extracted copy control bit; creating usage rule information which includes an encryption method of the broadcast contents if it is determined that the broadcast contents will be stored after being encrypted; extracting the copy control bit from each new broadcast content sequentially input and detecting broadcast contents which include copy control bits indicating that the broadcast contents will be stored without being encrypted; and encrypting the input broadcast contents through the broadcast contents before the detected broadcast contents using the encryption method and packaging and storing the encrypted broadcast contents and the usage rule information. Therefore, the unauthorized copying of broadcast contents transmitted through a digital broadcast receiver can be prevented.
摘要:
A method and apparatus for encrypting or decrypting digital content are provided. In the method, a binding range is selected from a plurality of binding ranges of content use based on license information of the content, and the content is encrypted based on the selected binding range so that the content can be used only within the selected binding range. Accordingly, it is possible to limit content use to a plurality of binding ranges of use of the content, using license information of the content.
摘要:
A scrambling apparatus and method are provided for increasing randomness without damaging compression efficiency of total video data by selectively and randomly performing conversion when converting motion vector codes of compressed video data into other motion vector codes indicating other motion vector values, and more particularly, by performing conditional conversion only if a predetermined condition is satisfied when selective conversion of motion vector codes is performed. The scrambling apparatus includes a conversion motion vector code table generator generating a conversion motion vector code table comprising motion vector codes obtained by converting motion vector codes corresponding to motion vector values of input video data in a standard motion vector code table; and a conversion controller randomly determining whether a certain motion vector value is encoded using the conversion motion vector code table or the standard motion vector code table.
摘要:
A method and apparatus are provided for simply and securely limiting a number of times that contents can be accessed using a hash chain. The apparatus limiting a number of times contents are accessed by a user terminal includes a hash chain generator receiving information indicating selected contents by the user terminal and information indicating how many times (n) the user terminal has authority to access the selected contents and generating a hash chain including n hash values derived from a seed value, and a contents access manager deleting the hash values one by one from the hash chain whenever the user terminal accesses the selected contents such that the number of times the contents can be accessed by the user terminal is decreased by the number of deleted hash values.
摘要:
The present invention relates to aromatic polyether resins crosslinked with amic acid or imide side chain, and more particularly, to the aromatic polyether resin crosslinked by amic acid or imide side chain, which is produced by heat curing of amic acid, wherein introduction of imide groups to the basic backbone provides excellent chemical resistance as well as heat resistance and improves surface roughness when coated as a thin film so that it can be suitable for films and flexible display plate substrate.
摘要:
A method of measuring round trip time (RTT) includes: chain-hashing at least one random number to create a plurality of hash values; (b) transmitting one of the created hash values to a device and starting to measure RTT of the device; and (c) receiving from the device a response to the transmitted hash value and ending the RTT measurement, thereby performing a more effective proximity check than a conventional proximity check requiring encryptions and decryptions of several tens of times through several thousands of times.
摘要:
A method of receiving a session key in a home network and a method of reproducing content using the same. The method of receiving a session key from a home server in a home network, includes: (a) whenever one of members of the home network changes, receiving and storing the session key and a session version indicating a session key generation sequence; (b) receiving a license necessary for reproducing predetermined content; and (c) determining a session key necessary for reproducing the predetermined content based on an encoding session version (ESV), which is a session version extracted from the license, and the stored session version. A home server transmits a session key and a session version to a user device whenever a subscriber to a home network changes, and the user device determines a session key using the session version, thereby performing a variety of domain administration by freely transmitting content between user devices.
摘要:
The present invention relates to a process of preparing polycarbonates and more particularly, to the process of preparing polycarbonates through a melt polymerization reaction of dihydroxyaryl compounds with diarylcarbonate, wherein said melt polymerization is performed in the presence of a mixed catalyst composed of an oxygen (O) or sulfur (S) containing compound having lone-pair electrons and an alkali metal or alkaline earth metal salt in an appropriate ratio at a reduced temperature by accelerating a reaction rate to obtain high quality polycarbonates with higher than 15,000 g/mole of a viscosity average molecular weight and improved color.