Patents by Inventor David H. Johnston

David H. Johnston 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: 11372123
    Abstract: Provided is a method for determining convergence in full wavefield inversion (FWI) of 4D seismic (time-lapse seismic: 3D seismic surveys acquired at different times with the first survey termed as the baseline and subsequent surveys termed as monitors). FWI applied to field seismic data includes iteratively solving for subsurface property models and model difference between monitor and baseline. Iteration occurs until the model difference is sufficiently converged. Rather than determining convergence by examining an entire subsurface region of the models and/or the model difference, subparts of the subsurface region models and/or the model difference are examined in order to determine convergence. For example, different regions behave differently, include the target reservoir region (where hydrocarbon is present) and the background region that is outside the target reservoir region.
    Type: Grant
    Filed: September 29, 2020
    Date of Patent: June 28, 2022
    Assignee: ExxonMobil Upstream Research Company
    Inventors: Ganglin Chen, Musa Maharramov, David H. Johnston, Partha Routh
  • Publication number: 20210103064
    Abstract: Provided is a method for determining convergence in full wavefield inversion (FWI) of 4D seismic (time-lapse seismic: 3D seismic surveys acquired at different times with the first survey termed as the baseline and subsequent surveys termed as monitors). FWI applied to field seismic data includes iteratively solving for subsurface property models and model difference between monitor and baseline. Iteration occurs until the model difference is sufficiently converged. Rather than determining convergence by examining an entire subsurface region of the models and/or the model difference, subparts of the subsurface region models and/or the model difference are examined in order to determine convergence. For example, different regions behave differently, include the target reservoir region (where hydrocarbon is present) and the background region that is outside the target reservoir region.
    Type: Application
    Filed: September 29, 2020
    Publication date: April 8, 2021
    Inventors: Ganglin Chen, Musa Maharramov, David H. Johnston, Partha Routh
  • Publication number: 20130254944
    Abstract: Soybean plants, germplasm, and seed comprising a mutant acetolactate synthase gene conferring improved herbicide tolerance, molecular markers useful for identifying and, optionally, selecting soybean plants displaying tolerance, improved tolerance, or susceptibility to a herbicide, and methods of their use are provided. Also provided are isolated polynucleotides, probes, kits, systems, and the like, useful for carrying out the methods described herein.
    Type: Application
    Filed: March 12, 2013
    Publication date: September 26, 2013
    Applicants: E.I. DU PONT DE NEMOURS AND COMPANY, PIONEER HI BRED INTERNATIONAL INC
    Inventors: JULIAN M. CHAKY, DAVID H. JOHNSTON, SCOTT A. SEBASTIAN, JOSHUA M. SHENDELMAN, STEPHEN D. STRACHAN, MARK VOGT, KAY L. WALTER, JOHN B. WOODWARD
  • Patent number: 7183502
    Abstract: An extendable channel unit such as molding unit (21) has a pair of telescopically arranged relatively extendable conduits (55, 75) with a conductor (22) interconnected in conductive relation between the conduits, with an intermediate section (137) of the conductor effective to accommodate the relative extension of the conduits. The intermediate section may include a sinuous configuration (133) or expandable coils (139). The channel unit may be installed along a wall (145) or other surface for decoratively covering the installation of the conductor for connection with an operated device (153). The channel unit may be installed into an extendable ramp (163) when installed along a floor, such as within a doorway (171). Two joints (308, 310) provide freedom of rotation about the conductor axis on opposed sides of an angled joint (312) that provides freedom of rotation about an axis disposed at a 45° angle to the axis of the conductor.
    Type: Grant
    Filed: April 24, 2006
    Date of Patent: February 27, 2007
    Inventors: David H. Johnston, Richard A. Clark
  • Patent number: 7034221
    Abstract: An extendable channel unit such as molding unit (21) has a pair of telescopically arranged relatively extendable conduits (55, 75) with a conductor (22) interconnected in conductive relation between the conduits, with an intermediate section (137) of the conductor effective to accommodate the relative extension of the conduits. The intermediate section may include a sinuous configuration (133) or expandable coils (139). The channel unit may be installed along a wall (145) or other surface for decoratively covering the installation of the conductor for connection with an operated device (153). The channel unit may be installed into a ramp (163) when installed along a floor, such as within a doorway (171).
    Type: Grant
    Filed: April 30, 2004
    Date of Patent: April 25, 2006
    Inventors: David H. Johnston, Richard A. Clark
  • Patent number: 6757217
    Abstract: Near-offset and far-offset seismic data volumes are time-aligned by first selecting a plurality of time shifts. The near-offset and far-offset seismic data volumes are cross-correlated at the plurality of time shifts. An initial time-shift volume and a maximum correlation volume are created from the maximal cross-correlations at the plurality of time shifts. Areas of high time shift from the initial time-shift volume and areas of low cross-correlation from the maximum correlation volume are determined. The determined areas of high time shift and low cross-correlation are filtered from the initial time-shift volume, generating a filtered time-shift volume. The filtered time-shift volume is applied to the far-offset seismic volume to generate a time-aligned far-offset volume.
    Type: Grant
    Filed: August 29, 2002
    Date of Patent: June 29, 2004
    Assignee: ExxonMobil Upstream Research Company
    Inventors: John E. Eastwood, Brian P. West, Michael D. Gross, Dwight C. Dawson, David H. Johnston
  • Patent number: 6662112
    Abstract: AVO anomalies are classified in near-offset and far-offset seismic data volumes, by first calculating a plurality of initial AVO seismic attributes representative of the offset seismic data volumes. A probabilistic neural network is constructed from the calculated initial AVO seismic attributes. AVO anomaly classifications are calculated in a portion of the offset seismic data volumes. The preceding steps are repeated until the calculated AVO anomaly classifications in the portion of the offset seismic data volumes are satisfactory. AVO anomaly classifications are calculated throughout the offset seismic data volumes using the constructed probabilistic neural network.
    Type: Grant
    Filed: August 29, 2002
    Date of Patent: December 9, 2003
    Assignee: ExxonMobil Upstream Research Company
    Inventors: John E. Eastwood, Brian P. West, Michael D. Gross, Dwight C. Dawson, David H. Johnston
  • Publication number: 20030043693
    Abstract: Near-offset and far-offset seismic data volumes are time-aligned by first selecting a plurality of time shifts. The near-offset and far-offset seismic data volumes are cross-correlated at the plurality of time shifts. An initial time-shift volume and a maximum correlation volume are created from the maximal cross-correlations at the plurality of time shifts. Areas of high time shift from the initial time-shift volume and areas of low cross-correlation from the maximum correlation volume are determined. The determined areas of high time shift and low cross-correlation are filtered from the initial time-shift volume, generating a filtered time-shift volume. The filtered time-shift volume is applied to the far-offset seismic volume to generate a time-aligned far-offset volume.
    Type: Application
    Filed: August 29, 2002
    Publication date: March 6, 2003
    Inventors: John E. Eastwood, Brian P. West, Michael D. Gross, Dwight C. Dawson, David H. Johnston
  • Publication number: 20030046006
    Abstract: AVO anomalies are classified in near-offset and far-offset seismic data volumes, by first calculating a plurality of initial AVO seismic attributes representative of the offset seismic data volumes. A probabilistic neural network is constructed from the calculated initial AVO seismic attributes. AVO anomaly classifications are calculated in a portion of the offset seismic data volumes. The preceding steps are repeated until the calculated AVO anomaly classifications in the portion of the offset seismic data volumes are satisfactory. AVO anomaly classifications are calculated throughout the offset seismic data volumes using the constructed probabilistic neural network.
    Type: Application
    Filed: August 29, 2002
    Publication date: March 6, 2003
    Applicant: EXXONMOBIL UPSTREAM RESEARCH COMPANY
    Inventors: John E. Eastwood, Brian P. West, Michael D. Gross, Dwight C. Dawson, David H. Johnston
  • Patent number: 4224381
    Abstract: A new and improved magnetic recording disk can be prepared by interposing between an aluminum substrate disk and a recording alloy layer a support layer located on the substrate disk and a shield layer located between the support layer and the recording layer. The support layer is a hard, semi-crystalline nickel alloy layer having magnetic properties which is of such a character that if it is contacted by a recording head during the use of the disk it will tend to form a powder which will not interfere with subsequent use of the disk or recording head. The shield layer is of a nonmagnetic metal and serves to reflect signals from the recording head so that they do not reach the support layer.
    Type: Grant
    Filed: October 19, 1978
    Date of Patent: September 23, 1980
    Assignee: Poly Disc Systems, Inc.
    Inventors: Pravin K. Patel, David H. Johnston, John Makaeff, deceased
  • Patent number: 4124736
    Abstract: It is known to manufacture a recording member having a substrate supporting a magnetic recording alloy on a surface and to locate a protective covering on the surface of the alloy remote from the substrate. An improved protective covering for use in this combination comprises a barrier layer located on the surface of the recording alloy and an oxide layer located on the surface of the barrier layer remote from the recording alloy. The barrier layer preferably consists of a nonmagnetic material. The oxide layer is also nonmagnetic and is sufficiently thick to protect the magnetic alloy layer against surface abrasion. The barrier layer isolates the oxide layer from the magnetic recording layer so as to preserve the character and uniformity of the magnetic recording layer as the oxide layer is created.
    Type: Grant
    Filed: October 29, 1974
    Date of Patent: November 7, 1978
    Assignee: Poly-Disc Systems, Inc.
    Inventors: Pravin K. Patel, David H. Johnston, John Makaeff