Patents by Inventor David F. Johnston

David F. 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: 11303232
    Abstract: A control system for mechanical braking devices is provided. The control system is designed to selectively slow, stop, and lock in place rotating machinery that is turning at an RPM that may be much greater than zero while helping minimize shock load on the rotating machinery. A fan brake control system is provided which can include: a fan brake; a position sensor; a microcontroller; an actuator; an operator interface; and a fan motor interface.
    Type: Grant
    Filed: August 28, 2019
    Date of Patent: April 12, 2022
    Assignee: Babcock & Wilcox SPIG, Inc.
    Inventors: Brian A Lesniak, Michael M Mahler, Thomas R Hendrix, John W Stacks, III, David F Johnston
  • Publication number: 20200076334
    Abstract: A control system for mechanical braking devices is provided. The control system is designed to selectively slow, stop, and lock in place rotating machinery that is turning at an RPM that may be much greater than zero while helping minimize shock load on the rotating machinery. A fan brake control system is provided which can include: a fan brake; a position sensor; a microcontroller; an actuator; an operator interface; and a fan motor interface.
    Type: Application
    Filed: August 28, 2019
    Publication date: March 5, 2020
    Inventors: Brian A. Lesniak, Michael M. Mahler, Thomas R. Hendrix, John W. Stacks, David F. Johnston
  • Patent number: 8409327
    Abstract: An electrostatic filter assembly configured to be installed in equipment for removing particulate matter entrained within a gas stream. The filter assembly functions in the removal and collection of the particulate matter from the gas stream. The equipment for removing particulate matter includes a high voltage discharge electrode for imparting an electric charge to the particulate matter whereby an electrical field is produced at the filter assembly. The filter assembly includes a filter element and a supporting structure for the filter element. The supporting structure is configured to establish at the filter assembly, under the operating conditions of the equipment for removing particulate matter, an electrical field having an intensity that produces no more than a selected amount of degradation at the filter element during operation of the equipment for removing particulate matter. Also a method of manufacturing such an electrostatic filter assembly.
    Type: Grant
    Filed: June 4, 2010
    Date of Patent: April 2, 2013
    Assignee: General Electric Company
    Inventors: Robert Taylor, Karim Younsi, David F. Johnston, Yingneng Zhou, Yaru Najem Mendez Hernandez, Prabhakar Neti
  • Patent number: 8404020
    Abstract: A method for monitoring operation of a rapper in an electrostatic precipitator using a rapper control system is described. The method includes determining model electrical characteristics of the rapper. The model electrical characteristics of the rapper correspond to model mechanical operating characteristics of the rapper. The method also includes storing data corresponding to the model electrical characteristics and the model mechanical operating characteristics of the rapper, determining actual electrical characteristics of the rapper, and comparing the actual electrical characteristics of the rapper to the stored model electrical characteristics to determine actual mechanical operating characteristics of the rapper.
    Type: Grant
    Filed: September 3, 2008
    Date of Patent: March 26, 2013
    Assignee: Babcock & Wilcox Power Generation Group, Inc.
    Inventors: Terry Lewis Farmer, Vivek Badami, Charles Erklin Seeley, David F. Johnston, Michael M. Mahler, Timothy Gerald Lawrence
  • Publication number: 20110296989
    Abstract: An electrostatic filter assembly configured to be installed in equipment for removing particulate matter entrained within a gas stream. The filter assembly functions in the removal and collection of the particulate matter from the gas stream. The equipment for removing particulate matter includes a high voltage discharge electrode for imparting an electric charge to the particulate matter whereby an electrical field is produced at the filter assembly. The filter assembly includes a filter element and a supporting structure for the filter element. The supporting structure is configured to establish at the filter assembly, under the operating conditions of the equipment for removing particulate matter, an electrical field having an intensity that produces no more than a selected amount of degradation at the filter element during operation of the equipment for removing particulate matter. Also a method of manufacturing such an electrostatic filter assembly.
    Type: Application
    Filed: June 4, 2010
    Publication date: December 8, 2011
    Applicant: BHA Group, Inc.
    Inventors: Robert Taylor, Karim Younsi, David F. Johnston, Yingneng Zhou, Yar+e,acu u+ee Najem M+e,acu e+ee ndez Hern+e,acu a+ee ndez, Prabhakar Neti
  • Patent number: 7809574
    Abstract: One aspect of the invention involves word recognition that uses scrollable choice lists in which choices are listed in character-order. Another aspect relates to a scrollable, visually-displayed word recognition choice list, where the recognition candidates on the choice list are each associated with a choice-selecting symbol the user can use to select a desired recognition candidate by pressing an associated button, and where the same choice-selecting symbol is used for different choices displayed on the display at different times as a result of scrolling. Another aspect of the invention relates to providing a choice list of best scoring characters for a particular character position in the spelling of a filter that is used to filter word recognition. Another aspect of the invention relates to a choice list used in word recognition in which the choice list can be scrolled horizontally.
    Type: Grant
    Filed: September 24, 2004
    Date of Patent: October 5, 2010
    Assignee: Voice Signal Technologies Inc.
    Inventors: Daniel L. Roth, Jordan R. Cohen, David F. Johnston, Edward W. Porter
  • Patent number: 7716058
    Abstract: Large vocabulary speech recognition can automatically turn recognition off in one or more ways. A user command can turn on recognition that is automatically turned off after the next end of utterance. A plurality of buttons can each be associated with a different speech mode and the touch of a given button can turn on, and then automatically turn off, the given button's associated speech recognition mode. These selectable modes can include large vocabulary and alphabetic entry modes, or continuous and discrete modes. A first user input can start recognition that allows a sequence of vocabulary words to be recognized and a second user input can start recognition that turns off after one word has been recognized. A first user input can start recognition that allows a sequence of utterances to be recognized and a second user input can start recognition that allows only a single utterance to be recognized.
    Type: Grant
    Filed: September 24, 2004
    Date of Patent: May 11, 2010
    Assignee: Voice Signal Technologies, Inc.
    Inventors: Daniel L. Roth, Jordan R. Cohen, David F. Johnston
  • Publication number: 20100057269
    Abstract: A method for monitoring operation of a rapper in an electrostatic precipitator using a rapper control system is described. The method includes determining model electrical characteristics of the rapper. The model electrical characteristics of the rapper correspond to model mechanical operating characteristics of the rapper. The method also includes storing data corresponding to the model electrical characteristics and the model mechanical operating characteristics of the rapper, determining actual electrical characteristics of the rapper, and comparing the actual electrical characteristics of the rapper to the stored model electrical characteristics to determine actual mechanical operating characteristics of the rapper.
    Type: Application
    Filed: September 3, 2008
    Publication date: March 4, 2010
    Inventors: Terry Lewis Farmer, Vivek Badami, Charles Erklin Seeley, David F. Johnston, Michael M. Mahler, Timothy Gerald Lawrence
  • Patent number: 7634403
    Abstract: Word recognition enables a user to have a selected transformation performed on a given word produced by word recognition. In one aspect of the invention, a selectable transformation changes the given word to a differently spelled word having the same word root. In another, a selectable transformation changes a given word to one or more of its homonyms. In yet another, a selectable transformation changes the given word between a representation that spells the word with letters and one that does not. In one aspect of the invention a user can select to display a choice list of transformed words corresponding to a given recognized word and then select to have one of the listed transformed words replace the given word. In another aspect of the invention word recognition favors recognition of words corresponding to a user selected part of speech.
    Type: Grant
    Filed: September 24, 2004
    Date of Patent: December 15, 2009
    Assignee: Voice Signal Technologies, Inc.
    Inventors: Daniel L. Roth, Jordan R. Cohen, David F. Johnston
  • Patent number: 7577569
    Abstract: Text-to-speech (TTS) generation is used in conjunction with large vocabulary speech recognition to say words selected by the speech recognition. The software for performing the large vocabulary speech recognition can share speech modeling data with the TTS software. TTS or recorded audio can be used to automatically say both recognized text and the names of recognized commands after their recognition. The TTS can automatically repeats text recognized by the speech recognition after each of a succession of end of utterance detections. A user can move a cursor back or forward in recognized text, and the TTS can speak one or more words at the cursor location after each such move. The speech recognition can be used to produces a choice list of possible recognition candidates and the TTS can be used to provide spoken output of one or more of the candidates on the choice list.
    Type: Grant
    Filed: September 24, 2004
    Date of Patent: August 18, 2009
    Assignee: Voice Signal Technologies, Inc.
    Inventors: Daniel L. Roth, Jordan R. Cohen, David F. Johnston, Manfred G. Grabherr, Edward W. Porter
  • Patent number: 7562556
    Abstract: An apparatus for cleaning a continuous emissions monitor system that is in fluid communication with a flue stack conducting exhaust gas from a combustion source. The apparatus comprises a housing and a probe mounted in the housing. The probe is tubular and in fluid communication with the flue stack to acquire a sample of gas from the flue stack. The probe tends to have deposits from the exhaust gas accumulate on the inner walls of the probe. A device imparts cleaning energy to the probe for dislodging accumulated deposits from the inner walls of the probe.
    Type: Grant
    Filed: October 2, 2006
    Date of Patent: July 21, 2009
    Assignee: General Electric Company
    Inventors: David F. Johnston, Jennifer Lynn Molaison, Terry Farmer, William Eberhardt, Mark Holt
  • Patent number: 7526431
    Abstract: Alphabetic filtering of the speech recognition of words uses a key press to indicate a desired character in an alphabetic filter string, where each key press represents two or more letters. The key presses can be disambiguated by recognizing a key-disambiguation utterance in association with a given key press. A user can select a desired recognition candidate from a choice list produced by such filtered word recognition. Ambiguous alphabetic filtering can be performed iteratively in response to the addition of successive ambiguous key presses. A user can select to re-recognize the utterance using filtering based on ambiguous key input after seeing the results of recognition without such filtering. Unambiguous alphabetic filtering can be performed by using multiple presses of an ambiguous key to disambiguate which letter is intended. A user can select between entering text by either large vocabulary speech recognition or by spelling text by pressing phone keys.
    Type: Grant
    Filed: September 24, 2004
    Date of Patent: April 28, 2009
    Assignee: Voice Signal Technologies, Inc.
    Inventors: Daniel L. Roth, Jordan R. Cohen, David F. Johnston
  • Patent number: 7505911
    Abstract: A handheld device with both large-vocabulary speech recognition and audio recoding allows users to switch between at least two of the following three modes: (1) recording audio without corresponding speech recognition; (2) recording with speech recognition; and (3) speech recognition without audio recording. A handheld device with both large-vocabulary speech recognition and audio recoding enables a user to select a portion of previously recorded sound and have speech recognition performed upon it. A system enables a user to search for a text label associated with portions of unrecognized recorded sound by uttering the label's words. A large-vocabulary system allows users to switch between playing back recorded audio and speech recognition with a single input, with successive audio playbacks automatically starting slightly before the end of prior playback. And a cell phone that allows both large-vocabulary speech recognition and audio recording and playback.
    Type: Grant
    Filed: December 5, 2004
    Date of Patent: March 17, 2009
    Inventors: Daniel L. Roth, Jordan R. Cohen, David F. Johnston, Edward W. Porter
  • Publication number: 20080078260
    Abstract: An apparatus for cleaning a continuous emissions monitor system that is in fluid communication with a flue stack conducting exhaust gas from a combustion source. The apparatus comprises a housing and a probe mounted in the housing. The probe is tubular and in fluid communication with the flue stack to acquire a sample of gas from the flue stack. The probe tends to have deposits from the exhaust gas accumulate on the inner walls of the probe. A device imparts cleaning energy to the probe for dislodging accumulated deposits from the inner walls of the probe.
    Type: Application
    Filed: October 2, 2006
    Publication date: April 3, 2008
    Inventors: David F. Johnston, Jennifer Lynn Molaison, Terry Farmer, William Eberhardt, Mark Holt
  • Patent number: 7313526
    Abstract: The present invention relates to speech recognition using selectable recognition modes. This includes innovations such as: large vocabulary speech recognition programming that supplies recognized words to external program as they are recognized, and allows a user to select between large vocabulary recognition of an utterance with and without language context from the prior utterance independently of state of the external program; allowing a user to select between continuous and discrete speech recognition that use substantially the same vocabulary; allowing a user to select between continuous and discrete large-vocabulary speech recognition modes; allowing a user to select between at least two different alphabetic entry speech recognition modes; and allowing a user to select from among four or more of the following recognitions modes when creating text: a large-vocabulary mode, an alphabetic entry mode, a number entry mode, and a punctuation entry mode.
    Type: Grant
    Filed: September 24, 2004
    Date of Patent: December 25, 2007
    Assignee: Voice Signal Technologies, Inc.
    Inventors: Daniel L. Roth, Jordan R. Cohen, David F. Johnston, Manfred G. Grabherr
  • Patent number: 7225130
    Abstract: The present invention relates to: speech recognition using selectable recognition modes; using choice lists in large-vocabulary speech recognition; enabling users to select word transformations; speech recognition that automatically turns recognition off in one or more specified ways; phone key control of large-vocabulary speech recognition; speech recognition using phone key alphabetic filtering and spelling: speech recognition that enables a user to perform re-utterance recognition; the combination of speech recognition and text-to-speech (TTS) generation; the combination of speech recognition with handwriting and/or character recognition; and the combination of large-vocabulary speech recognition with audio recording and playback.
    Type: Grant
    Filed: September 6, 2002
    Date of Patent: May 29, 2007
    Assignee: Voice Signal Technologies, Inc.
    Inventors: Daniel L. Roth, Jordan R. Cohen, David F. Johnston, Manfred G. Grabherr
  • Patent number: 6839251
    Abstract: An apparatus and method for controlling voltage applied to an electrostatic precipitator is disclosed. This apparatus includes a pulsating, direct current, voltage mechanism that is operable to receive power from a single phase, alternating current voltage source, and a spiral wound filter capacitor, wherein the pulsating, direct current, voltage mechanism is electrically connected in parallel to the spiral wound filter capacitor and the spiral wound filter capacitor is electrically connected in parallel to the electrostatic precipitator. Optionally, a resistor is present to lower the transient voltage rating of the spiral wound filter capacitor. A switching mechanism may be utilized to apply differing amounts of capacitance and inductance in order to apply a range of voltage waveforms to the electrostatic precipitator to potentially maximize particulate collection efficiency for the electrostatic precipitator.
    Type: Grant
    Filed: August 21, 2003
    Date of Patent: January 4, 2005
    Assignee: BHA Group Holdings, Inc.
    Inventors: David F. Johnston, Michael M. Mahler, Terry L. Farmer, Robert Edgar Hummell, III
  • Publication number: 20040267528
    Abstract: The present invention relates to: speech recognition using selectable recognition modes; using choice lists in large-vocabulary speech recognition; enabling users to select word transformations; speech recognition that automatically turns recognition off in one or more specified ways; phone key control of large-vocabulary speech recognition; speech recognition using phone key alphabetic filtering and spelling: speech recognition that enables a user to perform re-utterance recognition; the combination of speech recognition and text-to-speech (TTS) generation; the combination of speech recognition with handwriting and/or character recognition; and the combination of large-vocabulary speech recognition with audio recording and playback.
    Type: Application
    Filed: September 6, 2002
    Publication date: December 30, 2004
    Inventors: Daniel L. Roth, Jordan R. Cohen, David F. Johnston, Manfred G. Grabherr
  • Publication number: 20040049388
    Abstract: The present invention relates to: speech recognition using selectable recognition modes; using choice lists in large-vocabulary speech recognition; enabling users to select word transformations; speech recognition that automatically turns recognition off in one or more specified ways; phone key control of large-vocabulary speech recognition; speech recognition using phone key alphabetic filtering and spelling: speech recognition that enables a user to perform re-utterance recognition; the combination of speech recognition and text-to-speech (TTS) generation; the combination of speech recognition with handwriting and/or character recognition; and the combination of large-vocabulary speech recognition with audio recording and playback.
    Type: Application
    Filed: September 6, 2002
    Publication date: March 11, 2004
    Inventors: Daniel L. Roth, Jordan R. Cohen, David F. Johnston, Manfred G. Grabherr
  • Publication number: 20040037096
    Abstract: An apparatus and method for controlling voltage applied to an electrostatic precipitator is disclosed. This apparatus includes a pulsating, direct current, voltage mechanism that is operable to receive power from a single phase, alternating current voltage source, and a spiral wound filter capacitor, wherein the pulsating, direct current, voltage mechanism is electrically connected in parallel to the spiral wound filter capacitor and the spiral wound filter capacitor is electrically connected in parallel to the electrostatic precipitator. Optionally, a resistor is present to lower the transient voltage rating of the spiral wound filter capacitor. A switching mechanism may be utilized to apply differing amounts of capacitance and inductance in order to apply a range of voltage waveforms to the electrostatic precipitator to potentially maximize particulate collection efficiency for the electrostatic precipitator.
    Type: Application
    Filed: August 21, 2003
    Publication date: February 26, 2004
    Inventors: David F. Johnston, Michael M. Mahler, Terry L. Farmer, Robert Edgar Hummell