Patents by Inventor Xuan Bui

Xuan Bui 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: 7369342
    Abstract: Selection of servo signals for peak detection of timing based servo tracks of magnetic tape for lateral positioning of heads relative to the magnetic tape. Servo signals from magneto-resistive servo read head(s) reading a magnetic tape are digitized by analog to digital converter(s); digital peak measurement apparatus is configured to sense the digital converter(s), and provide positive peak values and negative peak values of the digitized servo signals; and control apparatus is configured to determine the greater of the provided positive peak values or negative peak values, and select servo signals having the greater values for a servo channel. Servo apparatus is configured to respond to the selected servo signals to control the lateral positioning of the servo read head(s).
    Type: Grant
    Filed: November 22, 2005
    Date of Patent: May 6, 2008
    Assignee: International Business Machines Corporation
    Inventors: Nhan Xuan Bui, Ernest Stewart Gale, Eiji Ogura, David Lee Swanson
  • Patent number: 7364106
    Abstract: Disclosed are a system, a method, and an article of manufacture to provide for the detection and compensation of tape breakage in a tape drive. The invention operates by simultaneously monitoring the tape reel rotation direction and the ratio of rotation between the tape reels. If the rotation direction is not the same for both reels, then tape breakage is indicated and reel rotation ceases. Tape breakage is also detected if the tape reel angular rotation ratio between the supply and take up reels is not within a specified tape reel ratio range. The tape reel angular rotation ratio is detected by simultaneously measuring the angular rotation of each tape reel in a specified time period and then calculating the ratio. The present invention detects the tape reel angular rotation ratio and if tape reel angular rotation ratio is outside of the specified tape reel ratio range, tape breakage is indicated and reel rotation ceases.
    Type: Grant
    Filed: February 13, 2007
    Date of Patent: April 29, 2008
    Assignee: International Business Machines Corporation
    Inventors: Nhan Xuan Bui, Junichi Fukuda, Randy Clark Inch, Eiji Ogura, Kazuhiro Tsuruta
  • Publication number: 20080074779
    Abstract: Multiple servo sensors are laterally displaced over a distance less than the transverse width of timing based servo track laterally extending transitions. The servo sensors are configured to sense the transitions, and servo detection logic detects the relative timings of the laterally extending transitions sensed by the laterally displaced servo sensors as the magnetic tape is moved in the longitudinal direction. Logic is configured to determine from the relative timings of the sensed transitions for at least one known set of laterally extending transitions having differing slants, the lateral position of a servo sensor by employing the relative timing detected from one servo sensor and the relative timing detected from another servo sensor, or determine the longitudinal velocity of the magnetic tape by determining the difference between the relative timing detected from one servo sensor and the relative timing detected from another servo sensor.
    Type: Application
    Filed: September 26, 2006
    Publication date: March 27, 2008
    Inventors: Allen Keith Bates, Nhan Xuan Bui, Mark Allan Taylor
  • Publication number: 20080055759
    Abstract: An apparatus, system, and method are disclosed for detecting a periodic sequence. A value detector module detects a plurality of values of a periodic sequence. In one embodiment, a transformation module transforms the plurality of values into transformed values. A confinement module confines the values to a limited set of confined values. A correlation module correlates the confined values with a plurality of instances of the periodic sequence. In addition, a selection module selects an instance of the periodic sequence with the highest correlation to the confined values as an observed periodic sequence.
    Type: Application
    Filed: August 31, 2006
    Publication date: March 6, 2008
    Inventors: Nhan Xuan Bui, Roy Daron Cideciyan, Robert Allen Hutchins, Thomas Mittelholzer, Kazuhiro Tsuruta
  • Publication number: 20070120304
    Abstract: A multi-axis chuck that rotates about at least two axes. Preferably, the axes are perpendicular. The multi-axis chuck includes a first portion, second portion, and third portion. Rear sides of the first portion and the second portion have a first mating portion that mates with a second mating portion provided on the second portion and the third portion, respectively. The mating portions enable the first portion and the second portion to be rotated about the axes. Preferably, the first portion rotates about a first axis independently of the second and third portions. Rotation of the second portion about a second axis preferably also rotates the first portion about the second axis. The multi-chuck is operatively connected to a motor, controller, and sensors. A user inputs a desired position into the controller that controls the motor. The motor rotates the multi-axis chuck to the desired position. The sensors are used to determine a position of the multi-axis chuck.
    Type: Application
    Filed: January 29, 2007
    Publication date: May 31, 2007
    Inventors: Xuan Bui, Michael Yang, Gilles Lefebvre
  • Patent number: 7177114
    Abstract: An apparatus, system, and method are disclosed for the velocity proportional clocking of time base servo tape storage devices. The apparatus, system, and method allow the velocity of time base servo tape storage devices to be adjusted and maintained by adjusting the frequency of a clock. In one embodiment, a velocity command is received and the clock signal frequency is varied in response to the command. A feedback control signal may then be produced to control the velocity of a time base servo device in response to the clock signal frequency, the feedback control signal being used to vary the velocity of a servo motor. In one embodiment, the velocity of the servo motor varies directly proportionate to the clock signal frequency.
    Type: Grant
    Filed: September 13, 2005
    Date of Patent: February 13, 2007
    Assignee: International Bussiness Machines Corporation
    Inventors: Nhan Xuan Bui, Robert Allen Hutchins, Eiji Ogura, Mark Allan Taylor, Kazuhiro Tsuruta
  • Patent number: 7175122
    Abstract: Disclosed are a system, a method, and an article of manufacture to provide for the detection and compensation of tape breakage in a tape drive. The invention operates by simultaneously monitoring the tape reel rotation direction and the ratio of rotation between the tape reels. If the rotation direction is not the same for both reels, then tape breakage is indicated and reel rotation ceases. Tape breakage is also detected if the tape reel angular rotation ratio between the supply and take up reels is not within a specified tape reel ratio range. The tape reel angular rotation ratio is detected by simultaneously measuring the angular rotation of each tape reel in a specified time period and then calculating the ratio. The present invention detects the tape reel angular rotation ratio and if tape reel angular rotation ratio is outside of the specified tape reel ratio range, tape breakage is indicated and reel rotation ceases.
    Type: Grant
    Filed: January 26, 2004
    Date of Patent: February 13, 2007
    Assignee: International Business Machines Corporation
    Inventors: Nhan Xuan Bui, Junichi Fukuda, Randy Clark Inch, Eiji Ogura, Kazuhiro Tsuruta
  • Patent number: 7102846
    Abstract: In a tape having separate servo bands of patterns positioned laterally across the tape, the patterns of a separate servo band have at least one differentiating characteristic with respect to patterns of another of the separate servo bands. The differentiating characteristic allows identification of the separate servo bands. For example, the patterns of a separate servo band have differing azimuthal orientations of detectable transitions with respect to another servo band, such as being laterally inverted. In another, variations in the width of gaps of patterns are made with respect to another servo band. In another, variations are made in the number of the detectable transitions of patterns with respect to the patterns of another servo band.
    Type: Grant
    Filed: August 29, 2005
    Date of Patent: September 5, 2006
    Assignee: International Business Machines Corporation
    Inventors: Nhan Xuan Bui, James Howard Eaton, Junichi Fukuda, Glen Alan Jaquette, Eiji Ogura, Mark Allan Taylor, Kazuhiro Tsuruta
  • Patent number: 7102847
    Abstract: In a tape having separate servo bands of patterns positioned laterally across the tape, the patterns of a separate servo band have at least one differentiating characteristic with respect to patterns of another of the separate servo bands. The differentiating characteristic allows identification of the separate servo bands. For example, the patterns of a separate servo band have differing azimuthal orientations of detectable transitions with respect to another servo band, such as being laterally inverted. In another, variations in the width of gaps of patterns are made with respect to another servo band. In another, variations are made in the number of the detectable transitions of patterns with respect to the patterns of another servo band.
    Type: Grant
    Filed: August 29, 2005
    Date of Patent: September 5, 2006
    Assignee: International Business Machines Corporation
    Inventors: Nhan Xuan Bui, James Howard Eaton, Junichi Fukuda, Glen Alan Jaquette, Eiji Ogura, Mark Allan Taylor, Kazuhiro Tsuruta
  • Publication number: 20060171857
    Abstract: A sample, or slide, retaining tray includes a reagent reservoir, or recess, and a reaction chamber. A slide, or other sample container, can be positioned on the sample retaining tray as desired, with a tissue specimen face down, between a platen on the tray and the slide. A reagent from the reservoir is rendered flowable, such as by heating, and flows from the reservoir into the reaction chamber. Optionally, reagents or other fluids can be provided from above, by dripping onto a drip surface of the sample retaining tray, or below via an inlet port in the platen.
    Type: Application
    Filed: February 3, 2006
    Publication date: August 3, 2006
    Inventors: Ronald Stead, Xuan Bui
  • Publication number: 20060169719
    Abstract: A manifold assembly that directs fluid to and from individually selectable sample receiving trays of a tissue processing system includes a manifold, fluid conduits machined in the manifold, and valves that may be selectively configured to provide a direct fluid path to or from a particular tray. The valves are controlled by a controller that positions each valve such that a desired path is created. Pressure is created in supply and/or drain bottles to supply or drain fluid from the trays supported by the manifold assembly. Independently operated heaters are provided on the manifold assembly to heat the trays to desired temperatures. Thermoelectric cooling elements may also provided to cool the heaters and/or trays.
    Type: Application
    Filed: February 6, 2006
    Publication date: August 3, 2006
    Inventor: Xuan Bui
  • Patent number: 7050409
    Abstract: A system and method providing a frame structure to received channel data sent over an air interface of a wireless communication system. The system and method may allow compensation for transmitting and receiving frequency variations, synchronization at the receiver, and provides a virtual signaling channel which may be used for system alarms and status. In one embodiment, the system uses bit stuffing, a frame preamble and a signaling preamble to transmit data at a high data rate in the ISM band.
    Type: Grant
    Filed: February 15, 2002
    Date of Patent: May 23, 2006
    Assignee: Wireless Facilities, Inc.
    Inventors: Cathal O'Scolai, Baya Hatim, Joseph J. Roy, Saeid Safavi, Ismail Lakkis, Hoang Xuan Bui, Deirdre O'Shea, Masood K. Tayebi
  • Patent number: 7006316
    Abstract: A method of estimating a writer/reader gap in a disk drive is disclosed. During a first revolution of the disk, a clock is synchronized to a first preamble and used to measure a write delay to write a second sync mark to the disk relative to a first sync mark. During a second revolution of the disk, the clock is again synchronized to the first preamble and used to measure a read delay required to detect the second sync mark relative to the first sync mark. The writer/reader gap is then estimated in response to the measured write delay and the measured read delay, for example, by computing a difference between the measured write delay and the measured read delay.
    Type: Grant
    Filed: August 16, 2004
    Date of Patent: February 28, 2006
    Assignee: Western Digital Technologies, Inc.
    Inventors: William A. Sargenti, Jr., Khoa Xuan Bui, Teik E E Yeo, Alvin W. Tan
  • Patent number: 7002763
    Abstract: In a tape having separate servo bands of patterns positioned laterally across the tape, the patterns of a separate servo band have at least one differentiating characteristic with respect to patterns of another of the separate servo bands. The differentiating characteristic allows identification of the separate servo bands. For example, the patterns of a separate servo band have differing azimuthal orientations of detectable transitions with respect to another servo band, such as being laterally inverted. In another, variations in the width of gaps of patterns are made with respect to another servo band. In another, variations are made in the number of the detectable transitions of patterns with respect to the patterns of another servo band.
    Type: Grant
    Filed: August 8, 2003
    Date of Patent: February 21, 2006
    Assignee: International Business Machines Corporation
    Inventors: Nhan Xuan Bui, James Howard Eaton, Junichi Fukuda, Glen Alan Jaquette, Eiji Ogura, Mark Allan Taylor, Kazuhiro Tsuruta
  • Patent number: 6940683
    Abstract: Disclosed are a system, a method, and article of manufacture to provide for filtering a servo signal in a tape drive using a matched filter that is optimized for the operating tape velocity of the tape drive. A servo controller for track following on a tape uses a digital filter implementation of the matched filter to produce a filtered servo signal. The digital filter is optimized for different tape velocities by selecting digital filter coefficients for the digital filter that depend upon the tape velocity presently in use. The filtered servo signal is used by the servo controller to provide improved track following in a tape drive.
    Type: Grant
    Filed: February 10, 2004
    Date of Patent: September 6, 2005
    Assignee: International Business Machines Corporation
    Inventors: David Berman, Nhan Xuan Bui, Michael Constantin Melas, Mark Allan Taylor
  • Patent number: 6940682
    Abstract: In a magnetic tape system, during lateral repositioning of a tape head between servo bands, the servo head is not on a servo band and is unable to provide servo position information. Hence, information about the lateral position may be lost. A control system selectively senses data read transducers of the tape head; and, upon detecting a servo signal of a servo band from a sensed data read transducer, determines the lateral position of the tape head with respect to the detected servo band based upon the position of the data read transducer that sensed the detected servo signal.
    Type: Grant
    Filed: September 10, 2003
    Date of Patent: September 6, 2005
    Assignee: International Business Machines Corporation
    Inventors: Nhan Xuan Bui, Robert Allen Hutchins, Glen Alan Jaquette, Larry Leeroy Tretter, Eiji Ogura, Kazuhiro Tsuruta
  • Patent number: 6937413
    Abstract: In magnetic tape having separate longitudinal servo bands of servo information with superimposed data information, the separate servo bands have selected different superimposed data information, to identify the separate servo bands for independent addressability. The servo information comprises non-parallel laterally extending transitions to indicate lateral positioning, and the selected different superimposed data information may comprise a lack thereof in portion(s) of the servo bands. Where the superimposed data information is longitudinal position information of the tape, the selected different superimposed data information may comprise different longitudinal position information of one or more servo band(s). The selected different superimposed data information may comprise a band identifier in the superimposed data information of one or more of the servo bands.
    Type: Grant
    Filed: August 8, 2003
    Date of Patent: August 30, 2005
    Assignee: International Business Machines Corporation
    Inventors: Nhan Xuan Bui, James Howard Eaton, Junichi Fukuda, Glen Alan Jaquette, Eiji Ogura, Mark Allan Taylor, Kazuhiro Tsuruta
  • Publication number: 20050161873
    Abstract: A multi-axis chuck that rotates about at least two axes. Preferably, the axes are perpendicular. The multi-axis chuck includes a first portion, second portion, and third portion. Rear sides of the first portion and the second portion have a first mating portion that mates with a second mating portion provided on the second portion and the third portion, respectively. The mating portions enable the first portion and the second portion to be rotated about the axes. Preferably, the first portion rotates about a first axis independently of the second and third portions. Rotation of the second portion about a second axis preferably also rotates the first portion about the second axis. The multi-chuck is operatively connected to a motor, controller, and sensors. A user inputs a desired position into the controller that controls the motor. The motor rotates the multi-axis chuck to the desired position. The sensors are used to determine a position of the multi-axis chuck.
    Type: Application
    Filed: January 22, 2004
    Publication date: July 28, 2005
    Inventors: Xuan Bui, Michael Yang, Gilles Lefebvre
  • Patent number: 6721126
    Abstract: A method and position control for a servo system for positioning a head laterally with respect to defined servo tracks. The servo system comprises a servo sensor and detector for sensing lateral position of the head and a compound actuator having a fine actuator portion and a coarse actuator portion. The position control provides position indications for the coarse actuator portion, which may comprise a table relating predetermined nominal lateral position indications to the defined servo tracks. The position control positions the coarse actuator portion at an estimated position with respect to the defined servo tracks, and responds to the servo sensor to determine which servo track is closest to the estimated position. The position control sets the coarse actuator portion position indication to the predetermined nominal lateral position indication of the closest defined servo track, e.g., by looking it up in the table. This thereby corrects the indication of the position of the coarse actuator portion.
    Type: Grant
    Filed: August 16, 2000
    Date of Patent: April 13, 2004
    Assignee: International Business Machines Corporation
    Inventors: Nhan Xuan Bui, John Alexander Koski, Akimitsu Sasaki, Kazuhiro Tsuruta
  • Patent number: 6710954
    Abstract: In a tape drive system performing read/write operations on a tape by inserting a tape cartridge into a tape drive, the tape cartridge having a tape on which servo and data tracks are arranged longitudinally and a predetermined servo pattern is recorded on each of the servo tracks, a method and system for re-setting coefficients of a low-pass filter for servo control of the tape drive, each time the tape cartridge is inserted into the tape drive so that a servo system of the tape drive is stabilized. More specifically, the servo pattern is read from the tape in the cartridge inserted into the tape drive, frequency analysis for the read servo pattern is performed, a singularity that exceeds a predetermined spectrum range is detected from frequency components obtained by the frequency analysis, and the coefficients of the low-pass filter are set so as to cancel a power spectrum of the singularity.
    Type: Grant
    Filed: August 16, 2001
    Date of Patent: March 23, 2004
    Assignee: International Business Machines Corporation
    Inventors: Nhan Xuan Bui, Tomoaki Kimura, Akimitsu Sasaki