Korea Kumho Petrochemical Co., Ltd.

Cplabs, Inc.

Seung Hwa Lee

Do Sung Kim

Joon Sun Uhr

Dong Hwan Kim

Gwanghoon Kwag

Young Chan Jang

Gwang Hoon Kwag

Seung Hwon Lee

Shin Han

A Ju Kim

Hyung Kyu Choi

Pil Sung Kim

Sung Hoon Han

Sanghyeon Park

Joonsun Uhr

Jeong Hyuk Lee

Sam Min Kim

Pilsung Kim

Jeonghyuk Lee

A method for providing oracle service of a blockchain network by using zero-knowledge proof includes steps of: (a) in response to feeder terminals registering data feeder transactions, including commitments generated with a commitment key and off-chain data, encrypted data generated by encrypting the off-chain data with a public key and data validation values proving with feeder zero-knowledge proof keys that the commitments are identical to the off-chain data, onto the blockchain network, the aggregator terminal acquiring at least one data feeder transaction therefrom; (b) the aggregator terminal verifying data validation values with its corresponding feeder zero-knowledge proof key, decrypting encrypted data with a private key, generating on-chain data from the decrypted data using a calculator and calculation validation values proving with an aggregator zero-knowledge proof key that the on-chain data is generated from the decrypted data, and registering the on-chain data and the calculation validation values onto the blockchain network.

Method for providing oracle service of blockchain network by using zero-knowledge proof and aggregator terminal using the same

A method for providing a user identity based on zero-knowledge proof over a blockchain network by using a user certificate is provided. The method includes steps of: an address abstraction smart contract (a) instructing the user terminal which made a user identity generating request to generate the user identity corresponding to the user certificate issued from a certification authority and generate a user identity proof by using user identity verifying parameters, the user identity, the user certificate and a certification authority public key, to thereby prove that the user identity is generated from the user certificate issued by the certification authority; and (b) upon receiving a user identity registering request from the user terminal, (i) verifying the user identity proof by using the user identity verifying parameters, the user identity, the certification authority public key and the user identity proof and (ii) registering the user identity upon successful verification.

Method for providing user identity based on zero-knowledge proof over blockchain network by using user certificate and blockchain system using the same

Disclosed is a novel high 1,4-cis polybutadiene-polyurethane copolymer and a preparation method thereof. The present invention provides a high 1,4-cis polybutadiene-polyurethane copolymer represented by the following formula 1 and having an average molecular weight of at least 100,000, and a method for preparing the high 1,4-cis polybutadiene-polyurethane copolymer that includes polymerizing 1,3-butadiene or butadiene derivatives with a catalyst comprising a rare earth compound, a halogen-containing compound and an organoaluminum compound in the presence of a non-polar solvent, to prepare a polybutadiene having a high 1,4-cis content of at least 95%; and then introducing a polyurethane group to the polybutadiene. The high 1,4-cis polybutadiene-polyurethane copolymer thus obtained exhibits low cold flow and high affinity to silica or carbon black in admixture as well as excellent in elasticity and abrasion resistance:  where l, m, n and o represent the number of repeating unit, 1 is 94 to 99%, m is 0 to 5%, n is 0 to 5%, l+m+n=100%, l/(m+n) is 15 to 100, o is 1 to 100%; and A and Y are C-Calkyl or aryl, respectively.

High 1,4-cis polybutadiene-polyurethane copolymer and preparation method thereof

The present invention relates to a method for preparing neodymium-carbon-nanotube and a process for preparing 1,4-cis-polybutadiene utilizing the same and more particularly, neodymium-carbon-nanotube. Neodymium is introduced by coordination with carboxylic acid, which is formed on the surface of carbon nanotube. In 1,3-butadiene polymerization with the neodymium-catalyst comprising the neodymium-carbon nanotube, a particular halogen compound, and a particular organometallic compound in an appropriate ratio, high 1,4-cis polybutadiene having molecular weight of 10,000 to 2,000,000 is produced, which exhibits excellent mechanical properties such as elasticity and durability.

Neodymium-carbon nanotube and method of preparing high 1,4-cis-polybutadiene using the same

This invention relates to a polymer film for smart window which can optionally modulate the intensity of light passing through a window on the part of users and more particularly, to the polymer film for smart window, prepared in a manner such that a polyalkylacrylate dispersion polymer containing dispersed dichroic particles, so synthesized via reaction between nickel picolinate and polyiodide, are dispersed in a polymethylphenyl-dimethylsiloxane copolymer as a film medium polymer, using dichlorodimethylsilane and dichloromethylphenylsilane as starting monomers where their molar ratios can be modulated. As such, the film medium polymer, so prepared by modulating its molecular weight distribution and dispersion degree of polymer, has an excellent combination of properties such as (1) the compatibility of the polymer to a dispersion polymer can be enhanced, (2) the dichroic particles can be homogeneously dispersed with the size of less than visible light wavelength, and (3) the permeability of light is modulated from the arrangement of particles induced by electric field, thus increasing the transparency of film itself.

Polymer film for smart window

Dichronic particles are developed for a window which varies the degree of light transmission at a user's desire, wherein the particles are obtained by reacting metal complexes of a transition metal (Co, Ni, Cu) and picolinic acid with polyiodine, dispersing into the particles an acrylate based polymer resin containing a plasticizer and injecting the particles between two conductive sheets of glass to be used for a window which varies the degree of light transmission in presence of electric field, to thereby improve stability to long exposure, color fastness, anti-clusteration, rapid changes in the degree of light transmission in the cases of absence and presence of electric field or power.

Particles of a window for varying the degree of light transmission in presence of electric field and uses thereof

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Seoul, South Korea

Seung Hwa Lee