Patents by Inventor Ryo HIROMASA

Ryo HIROMASA has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20240080185
    Abstract: A result confirmation unit (204) computes a state space probability that is a probability that a verification target device (300) has not correctly prepared a state space having a quantum state stored therein, a Pauli measurement probability that is a probability that the verification target device (300) has not correctly performed Pauli Z measurement and Pauli X measurement, and a magic state probability that is a probability that the verification target device (300) has not generated a magic state of CCZ. Then, using the state space probability, the Pauli measurement probability, and the magic state probability, the result confirmation unit (204) computes a degree of approximation between a quantum state and the magic state of CCZ at the verification target device (300) and measurement accuracies of the Pauli Z measurement and the Pauli X measurement on the quantum state at the verification target device (300).
    Type: Application
    Filed: October 31, 2023
    Publication date: March 7, 2024
    Applicants: Mitsubishi Electric Corporation, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Akihiro MIZUTANI, Ryo HIROMASA, Yusuke AIKAWA, Yuki TAKEUCHI, Seiichiro TANI
  • Publication number: 20230269068
    Abstract: A homomorphic inference device (500) divides a model ciphertext into a ciphertext for inference and a ciphertext for computation, generates a preliminary result ciphertext by a homomorphic operation algorithm without decrypting the ciphertext for computation and a data ciphertext, and generates an inference result ciphertext by a homomorphic operation algorithm, using the preliminary result ciphertext and the ciphertext for inference that have not been decrypted. A partial decryption device (600) generates a partial decryption result by performing partial decryption on the inference result ciphertext, using a model secret key. A final decryption device (700) decrypts an inference result from the partial decryption result, using a data secret key.
    Type: Application
    Filed: May 2, 2023
    Publication date: August 24, 2023
    Applicant: Mitsubishi Electric Corporation
    Inventor: Ryo HIROMASA
  • Publication number: 20230112699
    Abstract: An encryption apparatus (400) generates ciphertext data C of plaintext data x by [C=B·R+E+x·G], using a matrix B included in an encryption key PK used for homomorphic computation, a random-number matrix R, a random-number matrix E, and a tensor product G of a predetermined vector and a predetermined identity matrix. A circuit-confidentiality homomorphic computation apparatus (500) performs the homomorphic computation for the plaintext data x, using the encryption key PK and the ciphertext data C, and generates ciphertext data CX as a computation result of the homomorphic computation.
    Type: Application
    Filed: October 12, 2022
    Publication date: April 13, 2023
    Applicant: Mitsubishi Electric Corporation
    Inventor: Ryo HIROMASA
  • Patent number: 11522671
    Abstract: A range determination unit (412) takes as input an input ciphertext Ci resulting from encrypting input data, determines whether a value obtained from the input data is within a reference range, and generates a range ciphertext aj depending on a determined result. A result generation unit (413) performs a homomorphic operation on the range ciphertext aj generated by the range determination unit (412), so as to generate a result ciphertext D of a result of performing inference including a non-polynomial operation on the input data. An output unit (414) outputs the result ciphertext D.
    Type: Grant
    Filed: November 27, 2017
    Date of Patent: December 6, 2022
    Assignee: Mitsubishi Electric Corporation
    Inventor: Ryo Hiromasa
  • Patent number: 11374742
    Abstract: A key acquisition unit (411) acquires a decryption key ski in a pair of a conversion source and a public key pkj in a pair of a conversion target, out of a plurality of pairs of a decryption key and a public key. A conversion key generation unit (412) encrypts the decryption key ski acquired by the key acquisition unit (411) with the public key pkj, so as to generate a conversion key rki?j for converting a ciphertext encrypted with a public key pki in the pair of the conversion source into a converted ciphertext that can be decrypted with a decryption key skj in the pair of the conversion target. An output unit (413) outputs the conversion key rki?j generated by the conversion key generation unit (412).
    Type: Grant
    Filed: December 28, 2017
    Date of Patent: June 28, 2022
    Assignee: Mitsubishi Electric Corporation
    Inventors: Satoshi Yasuda, Yoshihiro Koseki, Yutaka Kawai, Ryo Hiromasa
  • Patent number: 11139952
    Abstract: An encryption device generates a ciphertext ct including an encryption element C in which a plaintext ? is set, an encryption element Cx in which an attribute x is set, and an encryption element F that is not to be decrypted with a decryption key skf corresponding to a policy f satisfied by the attribute x and in which the plaintext ? is set. A homomorphic computation device converts the ciphertext ct into a ciphertext ct˜ by converting, with the encryption element F, the encryption element C included in the ciphertext ct into an encryption element C˜ that can be decrypted with the decryption key skF corresponding to a policy set F acquired by a policy acquisition unit. The homomorphic computation device performs homomorphic computation g on the ciphertext ct˜ to generate a ciphertext ct*.
    Type: Grant
    Filed: January 18, 2017
    Date of Patent: October 5, 2021
    Assignee: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Ryo Hiromasa, Yutaka Kawai
  • Publication number: 20210211303
    Abstract: A key generation device (10) generates a pair of a secret key sk including an element s1 and a public key pk including an element a and an element t1. A signature device (20) generates a signature element z, which is an element of a signature ?, by computing a middle-product of a hash value c of a message ? and the element s1 of the secret key sk. A verification device (30) verifies the signature ? by computing a middle-product of the signature element z, which is an element of the signature ?, and the element a of the public key pk, and computing a middle-product of the hash value c, which is an element of the signature 6, and the element t1 of the public key pk.
    Type: Application
    Filed: March 23, 2021
    Publication date: July 8, 2021
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventor: Ryo HIROMASA
  • Publication number: 20200344049
    Abstract: A key acquisition unit (411) acquires a decryption key ski in a pair of a conversion source and a public key pkj in a pair of a conversion target, out of a plurality of pairs of a decryption key and a public key. A conversion key generation unit (412) encrypts the decryption key ski acquired by the key acquisition unit (411) with the public key pkj, so as to generate a conversion key rki?j for converting a ciphertext encrypted with a public key pki in the pair of the conversion source into a converted ciphertext that can be decrypted with a decryption key skj in the pair of the conversion target. An output unit (413) outputs the conversion key rki?j generated by the conversion key generation unit (412).
    Type: Application
    Filed: December 28, 2017
    Publication date: October 29, 2020
    Applicant: Mitsubishi Electric Corporation
    Inventors: Satoshi YASUDA, Yoshihiro KOSEKI, Yutaka KAWAI, Ryo HIROMASA
  • Publication number: 20200235908
    Abstract: A range determination unit (412) takes as input an input ciphertext Ci resulting from encrypting input data, determines whether a value obtained from the input data is within a reference range, and generates a range ciphertext aj depending on a determined result. A result generation unit (413) performs a homomorphic operation on the range ciphertext aj generated by the range determination unit (412), so as to generate a result ciphertext D of a result of performing inference including a non-polynomial operation on the input data. An output unit (414) outputs the result ciphertext D.
    Type: Application
    Filed: November 27, 2017
    Publication date: July 23, 2020
    Applicant: Mitsubishi Electric Corporation
    Inventor: Ryo HIROMASA
  • Publication number: 20200127810
    Abstract: An encryption device generates a ciphertext ct including an encryption element C in which a plaintext ? is set, an encryption element Cx in which an attribute x is set, and an encryption element F that is not to be decrypted with a decryption key skf corresponding to a policy f satisfied by the attribute x and in which the plaintext ? is set. A homomorphic computation device converts the ciphertext ct into a ciphertext ct˜ by converting, with the encryption element F, the encryption element C included in the ciphertext ct into an encryption element C˜ that can be decrypted with the decryption key skF corresponding to a policy set F acquired by a policy acquisition unit. The homomorphic computation device performs homomorphic computation g on the ciphertext ct˜ to generate a ciphertext ct*.
    Type: Application
    Filed: January 18, 2017
    Publication date: April 23, 2020
    Applicant: Mitsubishi Electric Corporation
    Inventors: Ryo HIROMASA, Yutaka KAWAI