Patents by Inventor David Hu

David Hu 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: 7427863
    Abstract: Method and system for calculating resistivity of an earth formation. At least some of the illustrative embodiments are methods comprising transmitting a current from a first current source, receiving at least part of the current at a first current return, said first current disposed remotely from the first current source, and measuring a first voltage at a monitor electrode, said monitor electrode disposed more remotely from below the first current source than said first current return.
    Type: Grant
    Filed: July 13, 2006
    Date of Patent: September 23, 2008
    Assignee: Halliburton Energy Services, Inc.
    Inventors: Michael S. Bittar, Guoyu (David) Hu, James Buchanan
  • Patent number: 7392579
    Abstract: A slider mounted CPP GMR or TMR read head sensor is protected from electrostatic discharge (ESD) damage and from noise and cross-talk from an adjacent write head by means of a balanced resistive/capacitative shunt. The shunt includes highly resistive interconnections between upper and lower shields of the read head and a grounded slider substrate and a low resistance interconnection between the lower pole piece of the write head and the substrate. The capacitances between the pole piece and the upper shield, the upper shield and the lower shield and the lower shield and the substrate are made equal by either forming the shields and pole piece with equal surface areas and separating them with dielectrics of equal thicknesses, or by keeping the ratio of area to insulator thicknesses equal.
    Type: Grant
    Filed: March 7, 2005
    Date of Patent: July 1, 2008
    Assignees: Headway Technologies, Inc., SAE Magnetics (HK) Ltd.
    Inventors: Eric Cheuk Wing Leung, Anthony Wai Yuen Lai, Pak Kin Wong, David Hu, Moris Dovek, Rod Lee
  • Patent number: 7385789
    Abstract: In order to obtain improved magnetic track density, it is desirable to bring the read and write elements as close to the recording surface as possible, short of actually touching it. This has been achieved by utilizing a magnetostrictive actuator, comprising single or multiple pairs of magnetostrictive elements and their associated conductor coils. A magnetic field is generated by passing electrical current through the conductor coils. This field will saturate the actuator and cause the magnetostrictive elements to contract or expand, thus moving the read/write element whenever so desired.
    Type: Grant
    Filed: April 30, 2004
    Date of Patent: June 10, 2008
    Assignee: Headway Technologies, Inc.
    Inventors: David Hu, Moris Dovek, Kowang Liu
  • Publication number: 20070087431
    Abstract: A cassette for preparing a sample is disclosed herein. The cassette includes a housing, which encloses the structures and the processes used to prepare the sample.
    Type: Application
    Filed: October 17, 2006
    Publication date: April 19, 2007
    Inventors: Jesus Ching, David Hu, Steve Yu, Phillip Lee
  • Publication number: 20070047124
    Abstract: A method for operating a head testing apparatus (spin stand) using a mounted hard disk that has had its servo track information pre-written in an external servo-writing apparatus rather than in the testing apparatus itself. This insures more accurate servo-track writing and renders the testing operation more efficient. The problem of repeatable runout (RRO) associated with the transfer of a disk written in one machine to another is eliminated by forming a corrected position error signal (PES) by subtracting the average offset of one or more servo sector locations previously calculated using limited bandwidth operation of the servomechanism, from the position error signal generated during full bandwidth servo operation of the apparatus.
    Type: Application
    Filed: September 1, 2005
    Publication date: March 1, 2007
    Inventors: Lou Shrinkle, David Hu, Peter Crill, Matthew Yee
  • Publication number: 20070016912
    Abstract: A plurality of batch lists are maintained by a channel in order to improve the efficiency of the channel in performing messaging between a sender and a receiver. For example, a Next Batch list is used to prefetch messages to be sent to the receiver from the sender; a Current Batch list includes the messages currently being transmitted to the receiver or waiting confirmation; and an Acknowledged Batch List includes the messages confirmed by the receiver. This allows the functions of prefetching messages, sending messages and deleting confirmed messages to be performed in parallel.
    Type: Application
    Filed: July 14, 2006
    Publication date: January 18, 2007
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Shawfu Chen, Robert Dryfoos, Allan Feldman, David Hu, Jason Keenaghan, Peter Lewis, Peter Sutton, Alice Williams-Obleton, Mei-Hui Wang
  • Patent number: 7154150
    Abstract: An ESD device and method using parasitic bipolar transistors that are silicided. The first embodiment is a parasitic Bipolar Junction Transistor comprised of n+/n?/p?/n?/n+ regions. The emitter is formed of the second N+ region and the second N? well. The parasitic base is formed by the p? substrate or well. The collector is formed of the first well and the first n+ region. The benefit of the first embodiment is the trigger voltage is lower because the junction between the n? well (emitter) and P? substrate (base) and the junction between P? substrate (base) and the n? well have lower cross over concentrations. The second embodiment is similar to the first embodiment with the addition of the first gate. The first gate is preferably connected to the first n+ region and the Vpad. The third embodiment contains the same elements as the second embodiment with the addition of a third n+ region. The third n+ region is preferably shorted (or connected) to the first p+ region and the second n+ region.
    Type: Grant
    Filed: August 26, 2004
    Date of Patent: December 26, 2006
    Assignee: Nano Silicon Pte. Ltd.
    Inventors: David Hu, Jun Cai
  • Publication number: 20060255811
    Abstract: A multi-mode oil base mud imager for use in non-conductive drilling fluid includes at least one current source—a current return pair, and one or more monitor electrodes not located between the current source and the current return of the current source—current return pair. Where more than one current source—current return pair is included, the tool is capable of multiple depths of investigation into surrounding formation. This data can be used as a gauge to establish the reliability of the data and to determine the resistance of the invaded zone around the borehole, as well as standoff distance of the tool from the borehole wall.
    Type: Application
    Filed: July 13, 2006
    Publication date: November 16, 2006
    Applicant: Halliburton Energy Services, Inc.
    Inventors: Michael Bittar, Guoyu (David) Hu, James Buchanan
  • Publication number: 20060198057
    Abstract: A slider mounted CPP GMR or TMR read head sensor is protected from electrostatic discharge (ESD) damage and from noise and cross-talk from an adjacent write head by means of a balanced resistive/capacitative shunt. The shunt includes highly resistive interconnections between upper and lower shields of the read head and a grounded slider substrate and a low resistance interconnection between the lower pole piece of the write head and the substrate. The capacitances between the pole piece and the upper shield, the upper shield and the lower shield and the lower shield and the substrate are made equal by either forming the shields and pole piece with equal surface areas and separating them with dielectrics of equal thicknesses, or by keeping the ratio of area to insulator thicknesses equal.
    Type: Application
    Filed: March 7, 2005
    Publication date: September 7, 2006
    Inventors: Eric Leung, Anthony Lai, Pak Wong, David Hu, Moris Dovek, Rod Lee
  • Patent number: 7098664
    Abstract: A multi-mode oil base mud imager for use in non-conductive drilling fluid includes at least one current source—a current return pair, and one or more monitor electrodes not located between the current source and the current return of the current source-current return pair. Where more than one current source-current return pair is included, the tool is capable of multiple depths of investigation into surrounding formation. This data can be used as a gauge to establish the reliability of the data and to determine the resistance of the invaded zone around the borehole, as well as standoff distance of the tool from the borehole wall.
    Type: Grant
    Filed: December 22, 2003
    Date of Patent: August 29, 2006
    Assignee: Halliburton Energy Services, Inc.
    Inventors: Michael S. Bittar, Guoyu (David) Hu, James Buchanan
  • Patent number: 7046010
    Abstract: A multi-mode resistivity tool measures at multiple depths into the near-borehole formation. By use of a four mode tool, measuring to four depths at the formation, a more accurate invasion zone resistivity measurement may be made than previously known. The tool itself is shown as including six concentric electrodes, although not every electrode is necessary for every mode.
    Type: Grant
    Filed: December 22, 2003
    Date of Patent: May 16, 2006
    Assignee: Halliburton Energy Services, Inc.
    Inventors: Guoyu (David) Hu, Michael S. Bittar
  • Patent number: 7042670
    Abstract: A system and method for adjusting the flying height of a magnetic head above a magnetic storage medium, such as a disk, is disclosed. A charging electrical pad may be coupled to the slider separate from the magnetic head to allow a charging electrical conductor to apply an electrical charge to the slider. By acting as a quasi-parallel capacitor, the amount of spacing in the head-disk interface may be increased or decreased based on the amount of voltage applied. The slider may be electrically isolated from the suspension. A feedback control system may monitor and control the head-disk spacing by measuring temperature or other environmental conditions surrounding the slider and disk.
    Type: Grant
    Filed: July 11, 2003
    Date of Patent: May 9, 2006
    Assignee: SAE Magnetics (H.K.) Ltd.
    Inventors: Zhu Feng, Ellis Cha, David Hu, Yen Fu
  • Patent number: 6977838
    Abstract: A method and system for providing a magnetic memory are disclosed. The method and system include providing a plurality of magnetic memory cells and at least one programmable current source. Each of the plurality of magnetic memory cells includes a first magnetic element. The programmable current source(s) are for programming a portion of the plurality of magnetic memory cells. Each of the programmable current source(s) includes a controller and a current source coupled to the controller. The controller is for determining a current provided by the current source and includes at least a second magnetic element. The second magnetic element(s) are substantially the same as the first magnetic element. The controller determines the current provided by the current source based on the at least the second magnetic element.
    Type: Grant
    Filed: February 17, 2004
    Date of Patent: December 20, 2005
    Assignees: Applied Spintronics Technology, Inc., Headway Technologies
    Inventors: David Tsang, Xizeng Shi, Po-Kang Wang, Hsu Kai (Karl) Yang, David Hu
  • Publication number: 20050243473
    Abstract: In order to obtain improved magnetic track density, it is desirable to bring the read and write elements as close to the recording surface as possible, short of actually touching it. This has been achieved by utilizing a magnetostrictive actuator, comprising single or multiple pairs of magnetostrictive elements and their associated conductor coils. A magnetic field is generated by passing electrical current through the conductor coils. This field will saturate the actuator and cause the magnetostrictive elements to contract or expand, thus moving the read/write element whenever so desired.
    Type: Application
    Filed: April 30, 2004
    Publication date: November 3, 2005
    Inventors: David Hu, Moris Dovek, Kowang Liu
  • Publication number: 20050180053
    Abstract: This structure and method for minimizing EME (Electromagnetic Emission) and the crosstalk between the signal lines which are used to write and read the tracks of magnetic disk drives. These signal lines are located on magnetic trace suspension assemblies which move above the magnetic disk drives. The structure and method utilize well-placed single and multiple crossovers on either or both of the lines used to read and write the tracks on magnetic disks. In addition, the structure and method utilize the parasitic capacitances between the write and read lines to couple beneficial voltages which cancel the unwanted crosstalk noise.
    Type: Application
    Filed: February 18, 2004
    Publication date: August 18, 2005
    Inventors: Moris Dovek, David Hu
  • Publication number: 20050134279
    Abstract: A multi-mode resistivity tool measures at multiple depths into the near-borehole formation. By use of a four mode tool, measuring to four depths at the formation, a more accurate invasion zone resistivity measurement may be made than previously known. The tool itself is shown as including six concentric electrodes, although not every electrode is necessary for every mode.
    Type: Application
    Filed: December 22, 2003
    Publication date: June 23, 2005
    Applicant: Halliburton Energy Services, Inc.
    Inventors: Guoyu (David) Hu, Michael Bittar
  • Publication number: 20050134280
    Abstract: A multi-mode oil base mud imager for use in non-conductive drilling fluid includes at least one current source—a current return pair, and one or more monitor electrodes not located between the current source and the current return of the current source—current return pair. Where more than one current source—current return pair is included, the tool is capable of multiple depths of investigation into surrounding formation. This data can be used as a gauge to establish the reliability of the data and to determine the resistance of the invaded zone around the borehole, as well as standoff distance of the tool from the borehole wall.
    Type: Application
    Filed: December 22, 2003
    Publication date: June 23, 2005
    Applicant: Halliburton Energy Services, Inc.
    Inventors: Michael Bittar, Guoyu (David) Hu, James Buchanan
  • Publication number: 20050036252
    Abstract: An ESD device and method using parasitic bipolar transistors that are silicided. The first embodiment is a parasitic Bipolar Junction Transistor comprised of n+/n?/p?/n?/n+ regions. The emitter is formed of the second N+ region and the second N? well. The parasitic base is formed by the p? substrate or well. The collector is formed of the first well and the first n+ region. The benefit of the first embodiment is the trigger voltage is lower because the junction between the n? well (emitter) and P? substrate (base) and the junction between P? substrate (base) and the n? well have lower cross over concentrations. The second embodiment is similar to the first embodiment with the addition of the first gate. The first gate is preferably connected to the first n+ region and the Vpad. The third embodiment contains the same elements as the second embodiment with the addition of a third n+ region. The third n+ region is preferably shorted (or connected) to the first p+ region and the second n+ region.
    Type: Application
    Filed: August 26, 2004
    Publication date: February 17, 2005
    Inventors: David Hu, Jun Cai
  • Publication number: 20050021348
    Abstract: Systems and techniques to allow a user to design and manage business solutions. The business solution management system (150) comprises a portal layer (112), an application layer (104) and a data repository (106). The portal layer (112) comprises at least first and second agents (204, 208). The application layer (104) comprises at least first and second software applications (220, 224). The first and second agents (204, 208) provide user interfaces to the first and second software applications (220, 224). The first software application (220) is operable to allow a user to design a business solution with user parameters and user-selectable, pre-defined business process objects and pre-defined technology objects. The second software application (224) is operable to allow a user to manage the business solution. The data repository (106) comprises the pre-defined business objects (316) and pre-defined technology objects (314).
    Type: Application
    Filed: July 21, 2003
    Publication date: January 27, 2005
    Inventors: Claribel Chan, David Hu, Tim Landvoigt, Charles Nelson, James Tarver
  • Publication number: 20050007687
    Abstract: A system and method for adjusting the flying height of a magnetic head above a magnetic storage medium, such as a disk, is disclosed. A charging electrical pad may be coupled to the slider separate from the magnetic head to allow a charging electrical conductor to apply an electrical charge to the slider. By acting as a quasi-parallel capacitor, the amount of spacing in the head-disk interface may be increased or decreased based on the amount of voltage applied. The slider may be electrically isolated from the suspension. A feedback control system may monitor and control the head-disk spacing by measuring temperature or other environmental conditions surrounding the slider and disk.
    Type: Application
    Filed: July 11, 2003
    Publication date: January 13, 2005
    Inventors: Zhu Feng, Ellis Cha, David Hu, Yen Fu