Patents by Inventor David A. J. Pearce

David A. J. Pearce 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: 8068748
    Abstract: A method and system to sense an amount of material such as toner in a container held in a horizontal position within a machine, such as a printing machine. A level sensor senses an amount of material within a dispensing unit which causes the level sensor to issue a signal. The dispensing unit is external to the container. The container holding the material is rotated, and a rotation direction reversed to a direction normally used to dispense the material. The reverse rotation direction moves the material to a closed end of the container. The container is then moved in a forward direction following the rotation of the container in the reverse direction. The forward rotation moves the material to the open end of the container, and the material further moves into the dispensing unit. A signal is generated when a sufficient amount of material has been moved into the dispensing unit.
    Type: Grant
    Filed: April 16, 2008
    Date of Patent: November 29, 2011
    Assignee: Xerox Corporation
    Inventors: David J. Pearce, Martin R. Walsh
  • Patent number: 8046219
    Abstract: A system, method, and apparatus for separating speech signal from a noisy acoustic environment. The separation process may include directional filtering, blind source separation, and dual input spectral subtraction noise suppressor. The input channels may include two omnidirectional microphones whose output is processed using phase delay filtering to form speech and noise beamforms. Further, the beamforms may be frequency corrected. The omnidirectional microphones generate one channel that is substantially only noise, and another channel that is a combination of noise and speech. A blind source separation algorithm augments the directional separation through statistical techniques. The noise signal and speech signal are then used to set process characteristics at a dual input noise spectral subtraction suppressor (DINS) to efficiently reduce or eliminate the noise component. In this way, the noise is effectively removed from the combination signal to generate a good qualify speech signal.
    Type: Grant
    Filed: October 18, 2007
    Date of Patent: October 25, 2011
    Assignee: Motorola Mobility, Inc.
    Inventors: Robert A. Zurek, Jeffrey M. Axelrod, Joel A. Clark, Holly L. Francois, Scott K. Isabelle, David J. Pearce, James A. Rex
  • Publication number: 20090263146
    Abstract: A method and system to sense an amount of material such as toner in a container held in a horizontal position within a machine, such as a printing machine. A level sensor senses an amount of material within a dispensing unit which causes the level sensor to issue a signal. The dispensing unit is external to the container. The container holding the material is rotated, and a rotation direction reversed to a direction normally used to dispense the material. The reverse rotation direction moves the material to a closed end of the container. The container is then moved in a forward direction following the rotation of the container in the reverse direction. The forward rotation moves the material to the open end of the container, and the material further moves into the dispensing unit. A signal is generated when a sufficient amount of material has been moved into the dispensing unit.
    Type: Application
    Filed: April 16, 2008
    Publication date: October 22, 2009
    Applicant: XEROX CORPORATION
    Inventors: David J. Pearce, Martin R. Walsh
  • Publication number: 20090106021
    Abstract: A system, method, and apparatus for separating speech signal from a noisy acoustic environment. The separation process may include directional filtering, blind source separation, and dual input spectral subtraction noise suppressor. The input channels may include two omnidirectional microphones whose output is processed using phase delay filtering to form speech and noise beamforms. Further, the beamforms may be frequency corrected. The omnidirectional microphones generate one channel that is substantially only noise, and another channel that is a combination of noise and speech. A blind source separation algorithm augments the directional separation through statistical techniques. The noise signal and speech signal are then used to set process characteristics at a dual input noise spectral subtraction suppressor (DINS) to efficiently reduce or eliminate the noise component. In this way, the noise is effectively removed from the combination signal to generate a good qualify speech signal.
    Type: Application
    Filed: October 18, 2007
    Publication date: April 23, 2009
    Applicant: Motorola, Inc.
    Inventors: Robert A. ZUREK, Jeffrey M. AXELROD, Joel A. CLARK, Holly L. FRANCOIS, Scott K. ISABELLE, David J. PEARCE, James A. REX
  • Patent number: 5754551
    Abstract: A method of connecting a new end station to a ring communication system for connecting a number of end stations is constituted by the steps of: i) sensing an attempt by the new end station to attach to the ring; ii) determining whether there is a single end station only existing on the ring; and, iiia) if it is determined that there is more than one end station on the ring, allowing the new end station to attach to the ring and maintaining the ring communication configuration; or b) if it is determined that there is a single end station only on the ring, breaking the ring configuration and setting up two separate communication paths between the new end station and the existing end station.
    Type: Grant
    Filed: July 7, 1995
    Date of Patent: May 19, 1998
    Assignee: Madge Networks Limited
    Inventors: Philip G. Claridge, David A. J. Pearce
  • Patent number: 5515404
    Abstract: A jitter generating device for use in a data communication system. The device has a repeating unit with an input and an output connected in use to receive data from the data communication system and to repeat the data onto the data communication system respectively. A clock signal generator generates a clock signal which is fed to the repeating unit to control the rate at which data is output onto the data communication system. A clock phase (jitter) modulating unit modulates the phase of the clock signal output by the clock signal generator.
    Type: Grant
    Filed: June 23, 1994
    Date of Patent: May 7, 1996
    Assignee: Madge Networks Limited
    Inventor: David A. J. Pearce
  • Patent number: 5436624
    Abstract: A communication system comprises a signal carrying medium (8) coupled to a series of end station ports (2-5). The end station ports (2-5) enable respective end stations (21) to transmit signals onto and receive signals from the medium (8). A controller (7) is provided to control the connection of the end stations (21) to the medium (8) via the ports (2-5). Monitors (9-12) are connected to the controller (7) to monitor characteristics of signals generated by the end stations (21) coupled to the ports. The monitors (9-12) are connected in parallel to the medium (8) and supply information relating to the monitored signals to the controller (7) in use. This system allows faulty end stations to be identified and removed from the system.
    Type: Grant
    Filed: January 21, 1993
    Date of Patent: July 25, 1995
    Assignee: Madge Network Limited
    Inventors: David A. J. Pearce, Mark K. Loney