Abstract: A computing method for privacy-preserving data analysis is provided, in which the computing method is performed by at least one processor and includes receiving a data analysis request including data-to-be-analyzed from a client, homomorphically encrypting the data-to-be-analyzed using an encryption engine, and uploading the homomorphically encrypted data-to-be-analyzed to a target path of a blockchain, and then, the method includes, based on the request to check analysis result, decrypting an analysis result of the homomorphically encrypted data stored in a designated path of the blockchain by using the encryption engine, and providing the decrypted analysis result to the client, in which the analysis result of the homomorphically encrypted data is data analyzed by a worker linked to the blockchain, and stored in a designated path in association with the target path of the blockchain.

Abstract: A computing method for privacy-preserving data analysis is provided, in which the computing method is performed by at least one processor and includes receiving a data analysis request including data-to-be-analyzed from a client, homomorphically encrypting the data-to-be-analyzed using an encryption engine, and uploading the homomorphically encrypted data-to-be-analyzed to a target path of a blockchain, and then, the method includes, based on the request to check analysis result, decrypting an analysis result of the homomorphically encrypted data stored in a designated path of the blockchain by using the encryption engine, and providing the decrypted analysis result to the client, in which the analysis result of the homomorphically encrypted data is data analyzed by a worker linked to the blockchain, and stored in a designated path in association with the target path of the blockchain.

Abstract: A method for managing states for a blockchain including a state database of a tree structure is provided, which includes: receiving a first transaction including a first state path and a first value from a client; generating a first set of state nodes for generating a state database of a current block, based on one or more state nodes included in a state database of a previous block existing on the first state path; setting a state of a specific state node of the generated first set of state nodes of the state database of the current block by using the first value; retrieving a first set of sibling state nodes for the one or more state nodes included in the state database of the previous block existing on the first state path; and associating the retrieved first set of sibling state nodes with the first set of state nodes of the state database of the current block.

Abstract: The present disclosure provides a method and a system for executing activity reward and advertisement transactions in an internet-based social networking service. The method includes transmitting, by a terminal of a first user, at least a portion of coins owned by the first user to a terminal of a second user in order to acquire a share of the second user; providing, by the terminal of the second user, the share to the first user according to a ratio of the funding amount transmitted by the first user with respect to a total funding amount received by the second user, and providing, by the terminal of the second user, at least a portion of activity reward given to the second user according to a share rate owned by the first user with respect to the second user.