Patents by Inventor Ryota Akiyama

Ryota Akiyama 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: 8021964
    Abstract: To provide a method of producing segmented chips preventing the chips from being damaged by the chip jumping or by the contact of the neighboring chips while the back surfaces thereof are being ground.
    Type: Grant
    Filed: June 18, 2007
    Date of Patent: September 20, 2011
    Assignee: 3M Innovative Properties Company
    Inventors: Ryota Akiyama, Kazuta Saito
  • Publication number: 20110151176
    Abstract: The present disclosure is to provide a method of manufacturing a wafer laminated body, a device for manufacturing a wafer laminated body, a wafer laminated body, a method of peeling a support body, and a method for manufacturing a wafer, all of which are capable of improving the grinding characteristic of the reverse surface of a wafer.
    Type: Application
    Filed: August 27, 2009
    Publication date: June 23, 2011
    Inventors: Ryota Akiyama, Shinya Nakajima, Kazuta Saito
  • Patent number: 7961871
    Abstract: A process, a device, and a computer-readable medium storing a program, for encryption. A conversion table having regions each of which stores 2i character codes associated with index values is provided, where i is a natural number predetermined for each region, the 2i character codes are defined in a predetermined character encoding scheme, and the index values have a minimum necessary bit length for uniquely identifying the 2i character codes within each region. First character codes constituting a plaintext are converted into index values by reference to respectively corresponding regions of the conversion table. Then, the index values are encrypted without changing the bit lengths, and the encrypted values are converted into second character codes associated with index values identical to the encrypted values by reference to the respectively corresponding regions of the conversion table, a sequence of the second character codes is outputted as an encrypted text.
    Type: Grant
    Filed: October 10, 2007
    Date of Patent: June 14, 2011
    Assignee: Fujitsu Broad Solution & Consulting Inc.
    Inventors: Shigeyuki Okubo, Ryota Akiyama
  • Publication number: 20100233867
    Abstract: To provide a method of producing segmented chips preventing the chips from being damaged by the chip jumping or by the contact of the neighboring chips while the back surfaces thereof are being ground.
    Type: Application
    Filed: June 18, 2007
    Publication date: September 16, 2010
    Inventors: Ryota Akiyama, Kazuta Saito
  • Patent number: 7555651
    Abstract: It is an object of the present invention to provide a time management apparatus and a time management method for reducing the opportunity for a third party to intentionally tamper with time. In order to achieve this object, the present invention is provided with time management apparatus including an external time fetching part for fetching an external time within a predetermined time span, a local clock part for outputting a self-advance time, and a time difference judgment part for calculating a difference between the external time fetched by the external time fetching part and the self-advance time output by the local clock part, setting the external time to the local clock part in a case where the difference is less than a predetermined value, and not setting the external time to the local clock part in a case where the difference is equal to or more than a predetermined value.
    Type: Grant
    Filed: February 22, 2005
    Date of Patent: June 30, 2009
    Assignee: Fujitsu Limited
    Inventors: Ryota Akiyama, Masamichi Ishibashi
  • Patent number: 7512801
    Abstract: The authentication system has a signing station and a certifying station. The signing station divides the data to be transmitted into a plurality of data, a hash unit creates a plurality of authenticators by applying a different one-way function to each of the data. In the certifying station, a separating unit divides the data into a plurality of data, a hash unit creates a plurality of authenticators by applying a different one-way function to each data, and a comparing unit compares the authenticators prepared anew with the authenticators separated from the received data and checks the authentication of the data from the comparison.
    Type: Grant
    Filed: September 24, 1999
    Date of Patent: March 31, 2009
    Assignee: Fujitsu Limited
    Inventors: Ryota Akiyama, Seigo Kotani, Takayuki Hasebe, Takaoki Sasaki
  • Patent number: 7421078
    Abstract: A valid medium issuing system reads a key Ka corresponding to an ID number from a key management book at a request from the script storage system to issue a script medium (MO), decrypts a valid medium certificate in a storage medium delivered from the factory using a key Ka, and generates a script medium (MO). The script medium (MO) is transmitted to the script storage system, and the script storage system records a script document on the script medium (MO). In this process, a decrypting process of a valid medium certificate is performed using the same key Ka, and after confirming the script of the storage medium, the script is recorded. With this configuration, a script document is recorded only for the script.
    Type: Grant
    Filed: July 30, 2002
    Date of Patent: September 2, 2008
    Assignee: Fujitsu Limited
    Inventor: Ryota Akiyama
  • Publication number: 20080144809
    Abstract: A process, a device, and a computer-readable medium storing a program, for encryption. A conversion table having regions each of which stores 2i character codes associated with index values is provided, where i is a natural number predetermined for each region, the 2i character codes are defined in a predetermined character encoding scheme, and the index values have a minimum necessary bit length for uniquely identifying the 2i character codes within each region. First character codes constituting a plaintext are converted into index values by reference to respectively corresponding regions of the conversion table. Then, the index values are encrypted without changing the bit lengths, and the encrypted values are converted into second character codes associated with index values identical to the encrypted values by reference to the respectively corresponding regions of the conversion table, a sequence of the second character codes is outputted as an encrypted text.
    Type: Application
    Filed: October 10, 2007
    Publication date: June 19, 2008
    Applicant: FUJITSU BROAD SOLUTION & CONSULTING INC.
    Inventors: Shigeyuki Okubo, Ryota Akiyama
  • Publication number: 20080022116
    Abstract: A time stamp apparatus that carries out e-signature including local time based on the local time output from an internal clock, includes an authentication time requesting unit that requests a time publishing apparatus for publishing an authentication time synchronous with standard time to publish the authentication time, an authentication time acquiring unit that acquires the authentication time published by the time publishing apparatus, a delay time calculating unit that calculates delay time included in the authentication time based on response time during which the authentication time requesting unit requests the publication and the authentication time acquiring unit acquires the authentication time, and a time correcting unit that corrects the local time using the authentication time based on the delay time calculated by the delay time calculating unit.
    Type: Application
    Filed: August 23, 2007
    Publication date: January 24, 2008
    Applicant: Fujitsu Limited
    Inventor: Ryota Akiyama
  • Publication number: 20070300065
    Abstract: A time stamp apparatus that carries out e-signature including local time based on the local time output from an internal clock, includes a radio wave time acquiring unit that receives a radio wave including standard time so as to acquire the standard time as radio wave time, an authentication time acquiring unit that acquires authentication time from a time publishing apparatus for publishing the authentication time synchronous with the standard time, and a time correcting unit that corrects the local time using the authentication time based on a difference between the radio wave time and the local time.
    Type: Application
    Filed: August 23, 2007
    Publication date: December 27, 2007
    Applicant: Fujitsu Limited
    Inventor: Ryota Akiyama
  • Patent number: 7257393
    Abstract: A local time is modified according to a radio wave time received from a time calibration signal transmitting station, as well as corrected according to an authentic time that is received from a time server when the difference between the local time and the radio wave time is less than a predetermined value as well as when the difference is equal to or greater than the predetermined value for a predetermined number of successive times. The local time is corrected while taking into consideration a delay period included in receiving the authentic time.
    Type: Grant
    Filed: July 7, 2005
    Date of Patent: August 14, 2007
    Assignees: Fujitsu Limited, Citizen Holdings Co., Ltd.
    Inventors: Ryota Akiyama, Takeaki Kawashima
  • Publication number: 20070064946
    Abstract: A computer-readable recording medium recording a character code encryption program capable of encrypting character codes without changing the data length. When plaintext is input, a plaintext encoder converts character codes included in the plaintext to corresponding numerical values. Then, an encryptor successively acquires the numerical values of the individual character codes, obtained by the plaintext encoder, to encrypt the first numerical value into an encrypted value with an identical number of bits, by using an initial value set in a register, and then to encrypt the rest of the input numerical values by alternately repeating updating of the register value by using at least part of the encrypted value and encryption of the numerical value by using the updated register value. A character code generator converts the individual encrypted values obtained by the encryptor to corresponding character codes, thereby generating ciphertext.
    Type: Application
    Filed: December 1, 2005
    Publication date: March 22, 2007
    Applicant: FUJITSU BROAD SOLUTION & CONSULTING INC.
    Inventors: Shigeyuki Ohkubo, Ryota Akiyama, Toshihiro Suzuki, Yuji Miyamoto, Takaoki Sasaki
  • Patent number: 7154824
    Abstract: A storage apparatus, capable of record or reproduce of an optical information recording medium in which ROM information is recorded with phase pits and RAM information is recorded on top of a recording region of the phase pits, has a main controller that, when the output of the recording information detection system—a system for detecting reflected light of a laser beam from the optical information recording medium and generating signals corresponding to ROM and RAM information—simultaneously contains ROM and RAM signals corresponding to ROM and RAM information, performs negative feedback control of a semiconductor laser emission using ROM signal in the output of the recording information detection system and performs control so as to obtain read-out and played-back ROM signal from the output of an optical intensity detection system for detecting the intensity of the laser light.
    Type: Grant
    Filed: July 7, 2004
    Date of Patent: December 26, 2006
    Assignee: Fujitsu Limited
    Inventors: Nobuhide Aoyama, Ryota Akiyama, Yasuaki Morimoto, Tetsuo Hosokawa
  • Publication number: 20060194573
    Abstract: A local time is modified according to a radio wave time received from a time calibration signal transmitting station, as well as corrected according to an authentic time that is received from a time server when the difference between the local time and the radio wave time is less than a predetermined value as well as when the difference is equal to or greater than the predetermined value for a predetermined number of successive times. The local time is corrected while taking into consideration a delay period included in receiving the authentic time.
    Type: Application
    Filed: July 7, 2005
    Publication date: August 31, 2006
    Inventors: Ryota Akiyama, Takeaki Kawashima
  • Publication number: 20060195697
    Abstract: A power supply controller controls power supply to each unit included in a time-stamping device. The power supply controller determines which unit is to be supplied with power according to the length of the period when the time-stamping device is not used. However, the power supply controller continuously supplies power to an authentication key storing unit that stores an authentication key for receiving an authentic time from a time server to prevent falsification of the local time of the time-stamping device.
    Type: Application
    Filed: July 11, 2005
    Publication date: August 31, 2006
    Inventors: Ryota Akiyama, Takeaki Kawashima
  • Patent number: 7013392
    Abstract: A file processing unit comprises a first signature information producing unit that produces first signature information in accordance with a predetermined rule utilizing the data of a file designated by a file close request issued in an application used in a computer system, and a signature information storage control unit that stores the first signature information, correlated with the file designated by the file close request, in a storage unit.
    Type: Grant
    Filed: April 27, 2000
    Date of Patent: March 14, 2006
    Assignee: Fujitsu Limited
    Inventors: Takaoki Sasaki, Takeshi Hatano, Ryota Akiyama, Seigo Kotani, Takayuki Hasebe
  • Patent number: 7010127
    Abstract: A cryptographic communication method is provided in which a cryptographic communication is performed by an easy operation even if both enciphered data and unenciphered data are mixed to be handled. In the transmission side, a communication key is used for enciphering data to be transmitted, and in the reception side the same communication key as in the transmission side is used for decoding received data. In the transmission side, an individual key that is different from the communication key is used for enciphering the data to be transmitted, the enciphered data are decoded by using the individual key first, and then the decoded data are enciphered by using the communication key so that the enciphered file can be transmitted.
    Type: Grant
    Filed: December 20, 2000
    Date of Patent: March 7, 2006
    Assignee: Fujitsu Limited
    Inventors: Seigo Kotani, Takaoki Sasaki, Yusuke Yamanaka, Takayuki Hasebe, Ryota Akiyama
  • Patent number: 7000114
    Abstract: In a signature creating apparatus, a clock generates a time stamp and in which time can be set only by a computer installed in a certificate authority center. Further, connecting sections connects an apparatus ID for specifying an apparatus and the time stamp and personal identification information for identifying an implementor to a plain-text so as to create data for the signature. A signature creating circuit encrypts the data for the signature using a signature creating key or the like and generates the signature. A connecting section connects the signature to the data for the signature and transmits the data as data after signature.
    Type: Grant
    Filed: April 14, 2000
    Date of Patent: February 14, 2006
    Assignee: Fujitsu Limited
    Inventors: Takayuki Hasebe, Seigo Kotani, Ryota Akiyama, Takaoki Sasaki
  • Patent number: RE39802
    Abstract: A storage medium stores encrypted electronic data, a medium personal number which is unique for each storage medium and encrypted permission information. At least the medium personal number is written onto the storage medium in an un-rewritable form which a user computer cannot rewrite.
    Type: Grant
    Filed: December 30, 1999
    Date of Patent: August 28, 2007
    Assignee: Fujitsu Limited
    Inventors: Takayuki Hasebe, Ryota Akiyama, Makoto Yoshioka
  • Patent number: RE40547
    Abstract: This invention provides an input switchover means for switching input routes according to the type of medium or communications, a software management means for decoding encrypted software information and for managing monetary charges according to the usage amounts of this software, an information conversion section for converting decoded data outputted from the previously mentioned software management means to visible or audible data, and an output route switchover means for outputting to the previously mentioned software management means encrypted software data, and for outputting to the previously mentioned information conversion section non-encrypted software information.
    Type: Grant
    Filed: September 5, 2000
    Date of Patent: October 21, 2008
    Assignee: Fujitsu Limited
    Inventors: Ryota Akiyama, Makoto Yoshioka