Patents by Inventor Ikuo Yamaguchi

Ikuo Yamaguchi 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).

  • Patent number: 9003202
    Abstract: A technique for improving data security is provided. To be specific, in a memory system including an information processing apparatus and a semiconductor memory device, the semiconductor memory device has an interface section that transmits, to the information processing apparatus, data read out from a memory core according to a plurality of communication protocols having different signal transmission/reception methods. Based on a switch command inputted from the information processing apparatus, a communication protocol selection section inputs, to the interface section, a selection signal for selecting a particular communication protocol from the plurality of communication protocols.
    Type: Grant
    Filed: April 5, 2010
    Date of Patent: April 7, 2015
    Assignee: MegaChips Corporation
    Inventors: Takahiko Sugahara, Tetsuo Furuichi, Ikuo Yamaguchi, Takashi Oshikiri
  • Patent number: 8826042
    Abstract: A technique allowing an improvement in the confidentiality of information stored in a memory device. A memory controller includes a key generation part that newly generates key information for use in encryption and decryption of information at every predetermined timing, and a data conversion circuit that encrypts information to be outputted to a memory device based on the information and decrypts encrypted information inputted from the memory device based on the key information. In the data conversion circuit, each time the key generation part generates new key information, key information is updated so as to set the new key information as the key information.
    Type: Grant
    Filed: April 5, 2010
    Date of Patent: September 2, 2014
    Assignee: MegaChips Corporation
    Inventors: Takahiko Sugahara, Tetsuo Furuichi, Ikuo Yamaguchi, Takashi Oshikiri
  • Patent number: 8140862
    Abstract: A memory device includes a storage unit having a decryption key storage section that stores key information for decryption and a data storage section that stores to-be-read data requested from the exterior, and a decryption control unit capable of decrypting an externally input encrypted read instruction and address based on the key information stored in the decryption key storage section, and causing data corresponding to the decrypted read instruction and address to be output from the data storage section. The decryption key storage section is composed of arrays of a flash memory.
    Type: Grant
    Filed: April 26, 2007
    Date of Patent: March 20, 2012
    Assignee: MegaChips Corporation
    Inventor: Ikuo Yamaguchi
  • Publication number: 20120023338
    Abstract: A technique for improving data security is provided. To be specific, in a memory system including an information processing apparatus and a semiconductor memory device, the semiconductor memory device has an interface section that transmits, to the information processing apparatus, data read out from a memory core according to a plurality of communication protocols having different signal transmission/reception methods. Based on a switch command inputted from the information processing apparatus, a communication protocol selection section inputs, to the interface section, a selection signal for selecting a particular communication protocol from the plurality of communication protocols.
    Type: Application
    Filed: April 5, 2010
    Publication date: January 26, 2012
    Applicant: MegaChips Corporation
    Inventors: Takahiko Sugahara, Tetsuo Furuichi, Ikuo Yamaguchi, Takashi Oshikiri
  • Publication number: 20120008772
    Abstract: A technique allowing an improvement in the confidentiality of information stored in a memory device. A memory controller includes a key generation part that newly generates key information for use in encryption and decryption of information at every predetermined timing, and a data conversion circuit that encrypts information to be outputted to a memory device based on the information and decrypts encrypted information inputted from the memory device based on the key information. In the data conversion circuit, each time the key generation part generates new key information, key information is updated so as to set the new key information as the key information.
    Type: Application
    Filed: April 5, 2010
    Publication date: January 12, 2012
    Applicant: MEGACHIPS CORPORATION
    Inventors: Takahiko Sugahara, Tetsuo Furuichi, Ikuo Yamaguchi, Takashi Oshikiri
  • Patent number: 7827417
    Abstract: A storage device includes a storage unit that stores key information. The storage device also includes an input/output unit that inputs a converted command. Further, the storage device includes an extractor that extracts attached information from the converted command inputted, reads out, from an address according to the attached information, the key information from the storage unit, and performs an inverse data conversion corresponding to a data conversion on the converted command, using the key information, to extract command information and address information. In addition, the storage device includes an output controller that, only when the command information is equivalent to predetermined information, reads out and outputs storage data from an address of the storage unit through the input/output unit, the address of the storage data indicated by the address information extracted by the extractor.
    Type: Grant
    Filed: October 28, 2005
    Date of Patent: November 2, 2010
    Inventor: Ikuo Yamaguchi
  • Patent number: 7770027
    Abstract: A semiconductor memory includes a memory control section and a memory core section. A command judgment circuit in the memory control section changes the operating mode of the semiconductor memory in response to a command sent from a controller of an information processing apparatus. In a first mode, a decryption process is performed in a command decryption circuit, and data outputted from the memory core section is not scrambled. In a second mode, the decryption process is not performed in the command decryption circuit, and the command outputted from the memory core section is scrambled.
    Type: Grant
    Filed: August 15, 2005
    Date of Patent: August 3, 2010
    Assignees: Nintendo Co., Ltd., MegaChips Corporation
    Inventors: Ryuji Umezu, Ikuo Yamaguchi
  • Patent number: 7696375
    Abstract: This invention provides a method for producing a lactic acid ester that can minimize input energy at the time of production, that can reduce chemical costs, and that can minimize equipment costs. This method comprises steps of: performing an esterification reaction in a reaction solution containing ammonium lactate obtained via fermentation and alcohol with an ammonia concentration of 1.0% by weight or lower; and recovering the lactic acid ester synthesized in the above step.
    Type: Grant
    Filed: June 27, 2006
    Date of Patent: April 13, 2010
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Shigeru Kuromiya, Osamu Saotome, Ikuo Yamaguchi, Kazunori Habu
  • Publication number: 20090104675
    Abstract: Lactic acid with high optical purity that has not previously been achieved is produced. It has been found that the optical purity of lactic acid is reduced as the racemization reaction of lactic acid proceeds when lactic acid coexists with glycerol. By reducing the amount of glycerol prior to concentrating lactic acid by heating, the optical purity of lactic acid after concentration by heating can be maintained at a high level.
    Type: Application
    Filed: November 20, 2008
    Publication date: April 23, 2009
    Inventors: Ikuo Yamaguchi, Osamu Saotome, Shigeru Kuromiya, Tohru Ohnishi, Noriko Yasutani, Satoshi Saitoh, Makoto Mouri, Mitsuru Nakano, Arimitsu Usuki, Nobuhiro Ishida, Kenro Tokuhiro, Eiji Nagamori, Haruo Takahashi
  • Publication number: 20090105501
    Abstract: This invention provides a method for producing a lactic acid ester that can minimize input energy at the time of production, that can reduce chemical costs, and that can minimize equipment costs. This method comprises steps of: performing an esterification reaction in a reaction solution containing ammonium lactate obtained via fermentation and alcohol with an ammonia concentration of 1.0% by weight or lower; and recovering the lactic acid ester synthesized in the above step.
    Type: Application
    Filed: June 27, 2006
    Publication date: April 23, 2009
    Inventors: Shigeru Kuromiya, Osamu Saotome, Ikuo Yamaguchi, Kazunori Habu
  • Publication number: 20070266242
    Abstract: A memory device includes a storage unit having a decryption key storage section that stores key information for decryption and a data storage section that stores to-be-read data requested from the exterior, and a decryption control unit capable of decrypting an externally input encrypted read instruction and address based on the key information stored in the decryption key storage section, and causing data corresponding to the decrypted read instruction and address to be output from the data storage section. The decryption key storage section is composed of arrays of a flash memory.
    Type: Application
    Filed: April 26, 2007
    Publication date: November 15, 2007
    Applicant: MegaChips Corporation
    Inventor: Ikuo YAMAGUCHI
  • Publication number: 20070161098
    Abstract: Lactic acid with high optical purity that has not previously been achieved is produced. It has been found that the optical purity of lactic acid is reduced as the racemization reaction of lactic acid proceeds when lactic acid coexists with glycerol. By reducing the amount of glycerol prior to concentrating lactic acid by heating, the optical purity of lactic acid after concentration by heating can be maintained at a high level.
    Type: Application
    Filed: September 7, 2005
    Publication date: July 12, 2007
    Inventors: Ikuo Yamaguchi, Osamu Saotome, Shigeru Kuromiya, Tohru Ohnishi, Noriko Yasutani, Satoshi Saitoh, Makoto Mouri, Mitsuru Nakano, Arimitsu Usuki, Nobuhiro Ishida, Kenro Tokuhiro, Eiji Nagamori, Haruo Takahashi
  • Publication number: 20060123247
    Abstract: After a parameter is extracted from an input command inputted from an input/output unit and key information corresponding to the parameter is read out from a storage unit, an inverse command converter performs inverse data conversions on the command and address information according to the key information. The input command has been converted a plurality of times, and it is impossible to predict key information necessary for inverse data conversion from the parameter included in the input command. Besides, output data is also converted by a data converter. Accordingly, it is difficult to analyze the contents of communications over the input/output unit from observation.
    Type: Application
    Filed: October 28, 2005
    Publication date: June 8, 2006
    Inventor: Ikuo Yamaguchi
  • Publication number: 20060107072
    Abstract: A semiconductor memory includes a memory control section and a memory core section. A command judgment circuit in the memory control section changes the operating mode of the semiconductor memory in response to a command sent from a controller of an information processing apparatus. In a first mode, a decryption process is performed in a command decryption circuit, and data outputted from the memory core section is not scrambled. In a second mode, the decryption process is not performed in the command decryption circuit, and the command outputted from the memory core section is scrambled.
    Type: Application
    Filed: August 15, 2005
    Publication date: May 18, 2006
    Inventors: Ryuji Umezu, Ikuo Yamaguchi
  • Patent number: 4620450
    Abstract: When tightening a screw member with a nut runner, the turning angle of the screw member and the tightening torque of the same are detected. The ratio of increase in torque to increase in the tightening turning angle, that is, the torque increasing rate is calculated. Tightening of the screw member is terminated when the force imparted to the screw member exceeds the elastic limit of the screw member and reaches a predetermined tightening point in the plastic range. The total tightening turning angle and the final tightening torque are detected upon termination of the tightening. The elastic tightening turning angle portion of the total tightening turning angle is calculated on the basis of the final tightening torque and the torque increasing rate in the elastic range, and the plastic tightening turning angle portion of the total tightening turning angle portion is calculated by subtracting the elastic tightening turning angle portion from the total tightening turning angle.
    Type: Grant
    Filed: August 5, 1985
    Date of Patent: November 4, 1986
    Assignee: Mazda Motor Corporation
    Inventor: Ikuo Yamaguchi