Patents by Inventor David R. Walker

David R. Walker 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: 11046925
    Abstract: Biogas production from the anaerobic digestion of juice in an ethanol production plant is maximized by mixing a juice containing thin stillage and/or water with a concentrated syrup prior to the anaerobic digestion. The juice then can be mixed with a biomass such as corn meal and enzymes to form a slurry suitable for fermentation. Sufficient syrup is mixed into the juice to provide a BOD concentration in the juice between 100,000 and 150,000 ppm. Enough biogas can be produced to supply enough energy to meet all of the boiler steam production/distillation energy/electrical generation demands for the ethanal production plant with some excess biogas left over for other uses.
    Type: Grant
    Filed: November 13, 2019
    Date of Patent: June 29, 2021
    Assignee: Dx Resources, LLC
    Inventor: David R. Walker
  • Patent number: 10698379
    Abstract: A device that provides for the non-invasive data monitoring of analog IO of a Programmable Logic Controller (PLC) system is described. The output is ultimately presented to a user audibly and/or visually on an interface in real-time and is measured directly from the IO channel. This type of device allows the accurate reading and analysis of errors and erroneous data within a device and transmission of said data to disparate secondary devices for use.
    Type: Grant
    Filed: September 24, 2018
    Date of Patent: June 30, 2020
    Assignee: FACTS Engineering, LLC
    Inventors: David R Walker, Thomas A Moulton, Goran Igic
  • Publication number: 20200148988
    Abstract: Biogas production from the anaerobic digestion of juice in an ethanol production plant is maximized by mixing a juice containing thin stillage and/or water with a concentrated syrup prior to the anaerobic digestion. The juice then can be mixed with a biomass such as corn meal and enzymes to form a slurry suitable for fermentation. Sufficient syrup is mixed into the juice to provide a BOD concentration in the juice between 100,000 and 150,000 ppm. Enough biogas can be produced to supply enough energy to meet all of the boiler steam production/distillation energy/electrical generation demands for the ethanal production plant with some excess biogas left over for other uses.
    Type: Application
    Filed: November 13, 2019
    Publication date: May 14, 2020
    Inventor: David R. Walker
  • Publication number: 20190025791
    Abstract: A device that provides for the non-invasive data monitoring of analog IO of a Programmable Logic Controller (PLC) system is described. The output is ultimately presented to a user audibly and/or visually on an interface in real-time and is measured directly from the IO channel. This type of device allows the accurate reading and analysis of errors and erroneous data within a device and transmission of said data to disparate secondary devices for use.
    Type: Application
    Filed: September 24, 2018
    Publication date: January 24, 2019
    Inventors: David R. Walker, Thomas A. Moulton, Goran Igic
  • Patent number: 10082782
    Abstract: A device that provides for the non-invasive data monitoring of analog IO of a Programmable Logic Controller (PLC) system. The output is ultimately displayed on an interface in real-time and is measured directly from the IO channel. This type of device allows the accurate reading and analysis of errors and erroneous data within a device and transmission of said data to disparate secondary devices for use.
    Type: Grant
    Filed: August 30, 2007
    Date of Patent: September 25, 2018
    Assignee: FACTS Engineering, LLC
    Inventors: David R. Walker, Goran Igic, Thomas A. Moulton, David A. White
  • Patent number: 9874698
    Abstract: A tunable PLC optical filter having sequentially connected thermally tunable Mach-Zehnder (MZ) interferometers is described. The cascade of MZ interferometers, each having a free spectral ranges matching ITU frequency grid spacing, are tuned so as to have a common passband centered on the frequency of the signal being selected, while having at least one of the stopbands centered on any other ITU frequency. Any other optical channel that may be present at any other ITU frequency is suppressed as a result. Another MZ interferometer in series with the cascade of interferometers including an asymmetric or variable coupler, is tuned to have low transmission at the center frequency of the selected optical channel.
    Type: Grant
    Filed: May 11, 2016
    Date of Patent: January 23, 2018
    Assignee: Lumentum Operations LLC
    Inventors: Barthelemy Fondeur, Jinxi Shen, Leonid Frenkel, Yimin Hua, David R. Walker, Yu Zhang, Vlatko Milinkovic
  • Publication number: 20170168241
    Abstract: A tunable PLC optical filter having sequentially connected thermally tunable Mach-Zehnder (MZ) interferometers is described. The cascade of MZ interferometers, each having a free spectral ranges matching ITU frequency grid spacing, are tuned so as to have a common passband centered on the frequency of the signal being selected, while having at least one of the stopbands centered on any other ITU frequency. Any other optical channel that may be present at any other ITU frequency is suppressed as a result. Another MZ interferometer in series with the cascade of interferometers including an asymmetric or variable coupler, is tuned to have low transmission at the center frequency of the selected optical channel.
    Type: Application
    Filed: May 11, 2016
    Publication date: June 15, 2017
    Inventors: Barthelemy FONDEUR, Jinxi SHEN, Leonid FRENKEL, Yimin HUA, David R. WALKER, Yu ZHANG, Vlatko MILINKOVIC
  • Publication number: 20160062208
    Abstract: A tunable PLC optical filter having sequentially connected thermally tunable Mach-Zehnder (MZ) interferometers is described. The cascade of MZ interferometers, each having a free spectral ranges matching ITU frequency grid spacing, are tuned so as to have a common passband centered on the frequency of the signal being selected, while having at least one of the stopbands centered on any other ITU frequency. Any other optical channel that may be present at any other ITU frequency is suppressed as a result. Another MZ interferometer in series with the cascade of interferometers including an asymmetric or variable coupler, is tuned to have low transmission at the center frequency of the selected optical channel.
    Type: Application
    Filed: November 12, 2015
    Publication date: March 3, 2016
    Inventors: Barthelemy FONDEUR, Jinxi SHEN, Leonid FRENKEL, Yimin HUA, David R. WALKER, Yu ZHANG, Vlatko MILINKOVIC
  • Publication number: 20140293393
    Abstract: A tunable PLC optical filter having sequentially connected thermally tunable Mach-Zehnder (MZ) interferometers is described. The cascade of MZ interferometers, each having a free spectral ranges matching ITU frequency grid spacing, are tuned so as to have a common passband centered on the frequency of the signal being selected, while having at least one of the stopbands centered on any other ITU frequency. Any other optical channel that may be present at any other ITU frequency is suppressed as a result. Another MZ interferometer in series with the cascade of interferometers including an asymmetric or variable coupler, is tuned to have low transmission at the center frequency of the selected optical channel.
    Type: Application
    Filed: March 28, 2013
    Publication date: October 2, 2014
    Inventors: Barthelemy FONDEUR, Jinxi SHEN, Leonid FRENKEL, Yimin HUA, David R. WALKER, Yu ZHANG, Vlatko MILINKOVIC
  • Patent number: 8731400
    Abstract: A tunable optical filter is configured to take point measurements at a few optical frequencies per frequency channel of a DWDM optical network. The measurement frequencies are shifted by pre-determined amounts relative to the optical frequency channel being characterized. Since the spectral shape of the tunable optical filter is known, the center optical frequency, the modulation bandwidth, and the total optical power of the channel can be obtained from as few as three optical measurements. The center optical frequency and the total optical power can be continuously monitored by providing a tunable filter stage coupled to an interleaver stage, and computing a ratio and a weighted sum the optical signals at the two outputs of the interleaver stage.
    Type: Grant
    Filed: April 9, 2012
    Date of Patent: May 20, 2014
    Assignee: JDS Uniphase Corporation
    Inventors: Jinxi Shen, David R. Walker, Leonid Frenkel, Yu Zhang, Barthelemy Fondeur, Vlatko Milinkovic, Yimin Hua
  • Patent number: 8674714
    Abstract: A system and method of probing work pieces is described. A first and second arm each having a pivot point and a guide end are pivotally coupled together at the respective pivot points. A probe tip holder is coupled to at least one of the first arm or the second arm. A guide means guides movement of the guide ends of the pivotally coupled arms, such that movement of the guide end of the first arm and the second arm move the probe tip holder in a plane parallel to the work piece surface.
    Type: Grant
    Filed: June 27, 2008
    Date of Patent: March 18, 2014
    Assignee: PPI Systems, Inc.
    Inventors: Anton Theodore Kitai, Paul Andrew Labelle, Robert Glenn Parker, David R. Walker
  • Publication number: 20130266313
    Abstract: A tunable optical filter is configured to take point measurements at a few optical frequencies per frequency channel of a DWDM optical network. The measurement frequencies are shifted by pre-determined amounts relative to the optical frequency channel being characterized. Since the spectral shape of the tunable optical filter is known, the center optical frequency, the modulation bandwidth, and the total optical power of the channel can be obtained from as few as three optical measurements. The center optical frequency and the total optical power can be continuously monitored by providing a tunable filter stage coupled to an interleaver stage, and computing a ratio and a weighted sum the optical signals at the two outputs of the interleaver stage.
    Type: Application
    Filed: April 9, 2012
    Publication date: October 10, 2013
    Inventors: Jinxi Shen, David R. Walker, Leonid Frenkel, Yu Zhang, Barthelemy Fondeur, Vlatko Milinkovic, Yimin Hua
  • Publication number: 20100271058
    Abstract: A system and method of probing work pieces is described. A first and second arm each having a pivot point and a guide end are pivotally coupled together at the respective pivot points. A probe tip holder is coupled to at least one of the first arm or the second arm. A guide means guides movement of the guide ends of the pivotally coupled arms, such that movement of the guide end of the first arm and the second arm move the probe tip holder in a plane parallel to the work piece surface.
    Type: Application
    Filed: June 27, 2008
    Publication date: October 28, 2010
    Applicant: PPI Systems, Inc.
    Inventors: Anton Theodore Kitai, Paul Andrew Labelle, Robert Glenn Parker, David R. Walker
  • Publication number: 20100216667
    Abstract: Disclosed is a system or matrix approach for determining compatibility of a pharmaceutically active substance, such as small molecule drug candidate, therapeutic proteins, peptides, vaccines or RNAi, with materials used in the research and development of pharmaceuticals, including plastics, polymers, resins, rubbers, elastomers, glass and steel.
    Type: Application
    Filed: December 17, 2009
    Publication date: August 26, 2010
    Inventors: Brian K. Meyer, Leonardo R. Allain, David Geer, Rajiv Mahajan, David R. Walker, Marc J. Kirchmeier
  • Publication number: 20090064026
    Abstract: A device that provides for the non-invasive data monitoring of analog IO of a Programmable Logic Controller (PLC) system. The output is ultimately displayed on an interface in real-time and is measured directly from the IO channel. This type of device allows the accurate reading and analysis of errors and erroneous data within a device and transmission of said data to disparate secondary devices for use.
    Type: Application
    Filed: August 30, 2007
    Publication date: March 5, 2009
    Inventors: David R. Walker, Goran Igic, Thomas A. Moulton, David A. White
  • Patent number: 6639004
    Abstract: An odor sorbing packaging material is prepared by applying to at least one surface of a flexible substrate an odor absorbing coating containing an effective concentration of activated carbon. The packaging material may be converted into packages, bags, pouches, liner members, wrappers or the like for packaging products and other materials that generate objectionable odors.
    Type: Grant
    Filed: July 12, 2001
    Date of Patent: October 28, 2003
    Assignee: Mead Westvaco Corporation
    Inventors: Ladislav Falat, James R. Miller, Mark E. Schiek, David R. Walker
  • Patent number: 6556744
    Abstract: The effects of dispersion of light on a link having an optical transmission fibre characterised by positive dispersion and large positive relative dispersion slope can be reduced by employing a sufficient length of dispersion compensating fibre (“DCF”) so that dispersion slope on the link is substantially nulled and the net dispersion of the link is made negative. Optical signals launched on the link with a positive chirp will be compensated for by the net negative dispersion.
    Type: Grant
    Filed: October 12, 2001
    Date of Patent: April 29, 2003
    Assignee: Nortel Networks Limited
    Inventors: Robert K. Brimacombe, David R. Walker
  • Publication number: 20020141961
    Abstract: An odor sorbing packaging material is prepared by applying to at least one surface of a flexible substrate an odor absorbing coating containing an effective concentration of activated carbon. The packaging material may be converted into packages, bags, pouches, liner members, wrappers or the like for packaging products and other materials that generate objectionable odors.
    Type: Application
    Filed: July 12, 2001
    Publication date: October 3, 2002
    Inventors: Ladislav Falat, James R. Miller, Mark E. Schiek, David R. Walker
  • Patent number: 6457348
    Abstract: A high-pressure high-velocity target inserter for use in steam cleaning. The target inserter uses an actuator connected to a tube assembly, which connects to a test line. The target inserter uses packing to prevent high-pressure steam from being released through the target inserter when the target rod is inserted and withdrawn from the line. In the preferred embodiment, the target rod passes through a remotely operated actuator controlled valve and a remotely controlled actuator controller, such that the operator is kept a safe distance away from the inserter when the access valve to the line is open.
    Type: Grant
    Filed: March 20, 2001
    Date of Patent: October 1, 2002
    Assignee: Onyx Industrial Services, Inc.
    Inventor: David R. Walker
  • Publication number: 20020134141
    Abstract: A high-pressure high-velocity target inserter for use in steam cleaning. The target inserter uses an actuator connected to a tube assembly, which connects to a test line. The target inserter uses packing to prevent high-pressure steam from being released through the target inserter when the target rod is inserted and withdrawn from the line. In the preferred embodiment, the target rod passes through a remotely operated actuator controlled valve and a remotely controlled actuator controller, such that the operator is kept a safe distance away from the inserter when the access valve to the line is open.
    Type: Application
    Filed: March 20, 2001
    Publication date: September 26, 2002
    Inventor: David R. Walker