Patents by Inventor Hiroto Takeshita

Hiroto Takeshita 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: 9336044
    Abstract: A parallel computer includes a plurality of calculation nodes and a management node. A calculation node includes a retention control unit that retains job information in a retention unit in association with an identification number, and the management node includes a retention control unit that retains the job information in a retention unit, retains, as a snapshot, job information of the same identification number in a case where the job information of the same identification number about a calculation node is detected in the retention unit. The retention unit of the calculation node includes a retention region enabling retention of job information corresponding to a plurality of periods, and the retention unit of the management node includes a retention region enabling retention of the job information corresponding to the plurality of periods with respect to each of the calculation nodes.
    Type: Grant
    Filed: February 27, 2013
    Date of Patent: May 10, 2016
    Assignee: FUJITSU LIMITED
    Inventor: Hiroto Takeshita
  • Patent number: 8785009
    Abstract: A magnetic recording medium includes a plurality of recording tracks magnetically continuous with respect to a recording direction and arranged intermittently in a track width direction, a plurality of recording dots intermittently formed in the recording tracks in the recording direction and a plurality of space dots alternately formed in the recording track with the recording dots in the recording direction and having a magnetic moment per unit area smaller than a magnetic moment per unit area of the recording dots.
    Type: Grant
    Filed: March 3, 2009
    Date of Patent: July 22, 2014
    Assignee: Fujitsu Limited
    Inventor: Hiroto Takeshita
  • Patent number: 8329249
    Abstract: Although dots and servo patterns are made of the same magnetic material, the dots have a relatively low coercive force so as to allow data deletion and rewrite by a magnetic head, while the servo patterns have a high coercive force compared with the coercive force of the dots. The coercive force of the servo patterns is strong enough so as to eliminate the influence of shape magnetic anisotropy.
    Type: Grant
    Filed: March 11, 2009
    Date of Patent: December 11, 2012
    Assignee: Fujitsu Limited
    Inventor: Hiroto Takeshita
  • Patent number: 8179637
    Abstract: A magnetic storage apparatus includes a magnetic storage medium including a recording layer, and a backing layer including a portion having a Curie temperature lower than that of the recording layer, a recording head that generates a magnetic field for recording from a side of the recording layer opposite to another side on which the backing layer is provided, and a heater unit heating at least a part of an area in proximity to a target area for recording by the recording head.
    Type: Grant
    Filed: June 10, 2009
    Date of Patent: May 15, 2012
    Assignee: Toshiba Storage Device Corporation
    Inventor: Hiroto Takeshita
  • Publication number: 20100097720
    Abstract: According to one embodiment, a magnetic recording/reproducing apparatus includes a magnetic head and a magnetic recording medium. The magnetic recording medium includes a recording layer formed of a hard magnetic layer and a soft magnetic layer. The hard magnetic layer has a bit width corresponding to a length of a bit island in a radial direction of the magnetic recording medium. The soft magnetic layer is arranged on the hard magnetic layer. The soft magnetic layer has a width smaller than the bit width and is arranged at a position displaced in a direction away from an off-track portion of the leading edge of the magnetic head skewed at an angle.
    Type: Application
    Filed: September 3, 2009
    Publication date: April 22, 2010
    Applicant: FUJITSU LIMITED
    Inventors: Nobutaka Ihara, Hiroto Takeshita, Yuji Ito
  • Publication number: 20100053811
    Abstract: A magnetic storage apparatus includes a magnetic storage medium including a recording layer, and a backing layer including a portion having a Curie temperature lower than that of the recording layer, a recording head that generates a magnetic field for recording from a side of the recording layer opposite to another side on which the backing layer is provided, and a heater unit heating at least a part of an area in proximity to a target area for recording by the recording head.
    Type: Application
    Filed: June 10, 2009
    Publication date: March 4, 2010
    Applicant: FUJITSU LIMITED
    Inventor: Hiroto Takeshita
  • Publication number: 20090311558
    Abstract: A magnetic recording medium that includes: a disc-shaped substrate; and plural magnetization retainers arranged on the disc-shaped substrate in plural circulations around a center of the substrate, each of the magnetization retainers having a length in a circumferential direction in such a manner that the length becomes longer as closer to outer circumference at least in a predetermined area, each retaining magnetization individually, each being formed of a magnetic material having axis of easy magnetization of magnetocrystalline anisotropy in a direction perpendicular to front and back surfaces of the substrate, each being filled with an ion that weakens the magnetocrystalline anisotropy of the magnetic material such that an amount of ion implantation becomes less as closer to the outer circumference in the predetermined area.
    Type: Application
    Filed: March 20, 2009
    Publication date: December 17, 2009
    Applicant: FUJITSU LIMITED
    Inventor: Hiroto Takeshita
  • Publication number: 20090305082
    Abstract: Although dots and servo patterns are made of the same magnetic material, the dots have a relatively low coercive force so as to allow data deletion and rewrite by a magnetic head, whilst the servo patterns have a high coercive force compared with the coercive force of the dots. The coercive force of the servo patterns is strong enough so as to eliminate the influence of shape magnetic anisotropy.
    Type: Application
    Filed: March 11, 2009
    Publication date: December 10, 2009
    Applicant: FUJITSU LIMITED
    Inventor: Hiroto Takeshita
  • Publication number: 20090296279
    Abstract: A magnetic recording medium including: a substrate; plural information recording members that are formed of a hard magnetic material on the substrate, in each of which magnetization in a direction crossing the substrate is generated and, when the information recording members pass in a predetermined traveling direction in a magnetic field for information recording, the magnetization is directed to a direction corresponding to a direction of the magnetic field and information is recorded; and a high-permeability film that is placed on an edge on a front side of the information recording members in the traveling direction and has a magnetic permeability higher than a magnetic permeability of the information recording members.
    Type: Application
    Filed: March 13, 2009
    Publication date: December 3, 2009
    Applicant: FUJITSU LIMITED
    Inventors: Nobutaka Ihara, Hiroto Takeshita, Yuji Ito
  • Publication number: 20090257148
    Abstract: There is provided a magnetic recording medium which contains a substrate in the shape of a disk, and a plural of recording bit formed on the substrate, wherein a bottom face of the recording bit is disposed so as to face the substrate, a top face of the recording bit is disposed so as to correspond to the bottom face of the recording bit, and Twb is larger than Twt, where Twb indicates a width of the bottom face with respect to a radius direction of the magnetic recording medium, and Twt indicates a width of the top face with respect to the radius direction.
    Type: Application
    Filed: December 17, 2008
    Publication date: October 15, 2009
    Applicant: FUJITSU LIMITED
    Inventors: Nobutaka Ihara, Hiroto Takeshita
  • Publication number: 20090225473
    Abstract: A magnetic recording medium includes a plurality of recording tracks magnetically continuous with respect to a recording direction and arranged intermittently in a track width direction, a plurality of recording dots intermittently formed in the recording tracks in the recording direction and a plurality of space dots alternately formed in the recording track with the recording dots in the recording direction and having a magnetic moment per unit area smaller than a magnetic moment per unit area of the recording dots.
    Type: Application
    Filed: March 3, 2009
    Publication date: September 10, 2009
    Applicant: FUJITSU LIMITED
    Inventor: Hiroto TAKESHITA
  • Patent number: 7402348
    Abstract: A magnetic recording layer is formed on an auxiliary magnetic layer in a perpendicular magnetic recording medium. The auxiliary magnetic layer has the axis of easy magnetization in the vertical direction perpendicular to the surface of a substrate. The perpendicular magnetic recording medium reliably allows establishment of the magnetization in the auxiliary magnetic layer in the vertical direction. When a magnetic flux flows along the vertical direction perpendicular to the surface of the magnetic recording layer, the magnetic flux flows across the magnetic recording layer in the vertical direction. The magnetization is thus reliably established in the magnetic recording layer in the vertical direction. The magnetic field of a stronger intensity is thus leaked out of the magnetic recording layer in the vertical direction.
    Type: Grant
    Filed: March 23, 2005
    Date of Patent: July 22, 2008
    Assignee: Fujitsu Limited
    Inventors: Hiroto Takeshita, Maki Maeda, Takuya Uzumaki
  • Publication number: 20070223139
    Abstract: The method of the present invention is capable of highly precisely producing a magnetic head. The method comprises the steps of: forming a pole end part of a magnetic layer, which becomes a magnetic pole and which is formed on a surface of a work piece on which the magnetic head will be formed, into a prescribed shape; coating at least a top part of the magnetic layer with a stopper layer; coating a surface of the work piece, on which the stopper layer has been formed, with an insulating layer, whose polishing rate is higher than that of the stopper layer; polishing the surface of the work piece until the stopper layer, which coats the top part of the magnetic layer, is exposed from the insulating layer; and removing the stopper layer, which has been exposed in a surface of the magnetic layer.
    Type: Application
    Filed: August 23, 2006
    Publication date: September 27, 2007
    Inventors: Masanori Tachibana, Hiroto Takeshita
  • Patent number: 7258893
    Abstract: A method of fabricating a magnetic recording medium is disclosed, including a monomolecular film formation step of forming a monomolecular film on a substrate and a magnetic film formation step of forming on the monomolecular film a magnetic film for recording magnetic information. In the monomolecular film formation step, it is preferable to form a perylene-based organic monomolecular film.
    Type: Grant
    Filed: November 7, 2003
    Date of Patent: August 21, 2007
    Assignee: Fujitsu Limited
    Inventors: Hiroto Takeshita, Takuya Uzumaki
  • Patent number: 7147940
    Abstract: The present invention provides a perpendicular magnetic recording medium that reduces medium noise and achieves thermal stability of recording magnetization. This perpendicular magnetic recording medium has a substrate and a recording layer formed by single-layered magnetic nanoparticles that are aligned at uniform intervals. An auxiliary magnetic film that is thinner than the recording layer is interposed between the substrate and the recording layer. The magnetization of the magnetic nanoparticles is secured by the exchange interaction effect of the auxiliary magnetic film.
    Type: Grant
    Filed: January 17, 2003
    Date of Patent: December 12, 2006
    Assignee: Fujitsu Limited
    Inventors: Maki Maeda, Hiroto Takeshita, Takuya Uzumaki
  • Publication number: 20050249982
    Abstract: A magnetic recording layer is formed on an auxiliary magnetic layer in a perpendicular magnetic recording medium. The auxiliary magnetic layer has the axis of easy magnetization in the vertical direction perpendicular to the surface of a substrate. The perpendicular magnetic recording medium reliably allows establishment of the magnetization in the auxiliary magnetic layer in the vertical direction. When a magnetic flux flows along the vertical direction perpendicular to the surface of the magnetic recording layer, the magnetic flux flows across the magnetic recording layer in the vertical direction. The magnetization is thus reliably established in the magnetic recording layer in the vertical direction. The magnetic field of a stronger intensity is thus leaked out of the magnetic recording layer in the vertical direction.
    Type: Application
    Filed: March 23, 2005
    Publication date: November 10, 2005
    Inventors: Hiroto Takeshita, Maki Maeda, Takuya Uzumaki
  • Publication number: 20050196649
    Abstract: A perpendicular magnetic recording medium includes a magnetic orientation controller layer serving as a layer for controlling crystalline orientation in an upper layer. A non-magnetic orientation controller layer extends on the surface of the magnetic orientation controller layer The non-magnetic orientation controller layer serves as a layer for controlling crystalline orientation in an upper layer. A magnetic recording layer extends on the surface of the non-magnetic orientation controller layer. The perpendicular magnetic recording medium allows a reliable establishment of a uniform crystalline orientation in the magnetic recording layer based on the influences from the magnetic and non-magnetic orientation controller layers. A reliable establishment of a uniform crystalline orientation can be achieved without an increase in the thickness of the non-magnetic orientation controller layer.
    Type: Application
    Filed: March 28, 2005
    Publication date: September 8, 2005
    Inventors: Ryosaku Inamura, Hiroto Takeshita, Toshio Sugimoto, Kazumasa Shimoda, Takenori Oshima, Maki Maeda, Takuya Uzumaki, Atsushi Tanaka
  • Patent number: 6835444
    Abstract: A magnetic recording medium is provided. The magnetic recording medium comprises an in-plane magnetic film used for recording, and a perpendicular magnetic film formed on the in-plane magnetic film. The in-plane magnetic film has a magnetization easy axis in an in-plane direction. The perpendicular magnetic film has a magnetization easy axis oriented in a direction perpendicular to the magnetization easy axis of the in-plane magnetic film. A tBr (a product of a thickness and a residual magnetization) of the perpendicular magnetic film is set so as not to exceed one-fifth of a tBr of the in-plane magnetic film at the maximum.
    Type: Grant
    Filed: October 12, 2001
    Date of Patent: December 28, 2004
    Assignee: Fujitsu Limited
    Inventors: Maki Maeda, Hiroto Takeshita, Takuya Uzumaki, Atsushi Tanaka
  • Patent number: 6809893
    Abstract: A storage system has a storage medium, a head, and a control unit for carrying out refresh processing. A refresh operation extracts data that needs to be refreshed by measuring the read-out output level of target data. Then, data requiring refresh is re-recorded to the storage medium by the head. Because an actual data level is observed, it is possible to accurately detect refresh target data, and because there is no need for a reference area, it is possible to prevent a reduction in storage capacity.
    Type: Grant
    Filed: January 26, 2001
    Date of Patent: October 26, 2004
    Assignee: Fujitsu Limited
    Inventors: Takuya Uzumaki, Kazumasa Shimoda, Hiroto Takeshita, Atsushi Tanaka
  • Patent number: 6773782
    Abstract: The surface of a disk medium includes a substrate whose surface includes grooves and lands. A non-magnetic underlayer and a magnetic recording layer are formed on the substrate. Smoothing non-magnetic film fills the grooves, which are covered with the non-magnetic underlayer and the magnetic recording layer, so that the height of the magnetic recording layer above the grooves may reach the same level as the height of the magnetic recording layer above the lands.
    Type: Grant
    Filed: November 21, 2001
    Date of Patent: August 10, 2004
    Assignee: Fujitsu Limited
    Inventors: Hiroto Takeshita, Wataru Yamagishi