Patents by Inventor Yifan Zhao

Yifan Zhao 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).

  • Publication number: 20190080455
    Abstract: Embodiments of the present invention provide a method and a device for three-dimensional feature-embedded image object component-level semantic segmentation, the method includes: acquiring three-dimensional feature information of a target two-dimensional image; performing a component-level semantic segmentation on the target two-dimensional image according to the three-dimensional feature information of the target two-dimensional image and two-dimensional feature information of the target two-dimensional image. In the technical solution of the present application, not only the two-dimensional feature information of the image but also the three-dimensional feature information of the image are taken into consideration when performing the component-level semantic segmentation on the image, thereby improving the accuracy of the image component-level semantic segmentation.
    Type: Application
    Filed: January 15, 2018
    Publication date: March 14, 2019
    Inventors: XIAOWU CHEN, JIA LI, YAFEI SONG, YIFAN ZHAO, QINPING ZHAO
  • Patent number: 8687362
    Abstract: A portable briefcase office comprises of a computer unit, a storage unit, and a supplies and devices unit. It integrates a computer, printer, projector, storage space, battery, and other office supplies in one easily transported briefcase. It is not a case for devices, but a compact apparatus that incorporates these devices as it would appear in an entire office.
    Type: Grant
    Filed: May 2, 2012
    Date of Patent: April 1, 2014
    Inventor: Yifan Zhao
  • Publication number: 20130294021
    Abstract: A portable briefcase office comprises of a computer unit, a storage unit, and a supplies and devices unit. It integrates a computer, printer, projector, storage space, battery, and other office supplies in one easily transported briefcase. It is not a case for devices, but a compact apparatus that incorporates these devices as it would appear in an entire office.
    Type: Application
    Filed: May 2, 2012
    Publication date: November 7, 2013
    Inventor: Yifan Zhao
  • Patent number: 7190145
    Abstract: A method and apparatus for improving speed measurement quality in systems having multi-pole machines is taught. The method compensates for pole misalignment by computing speed based upon moving average techniques. In one embodiment, a moving average speed averaged over a complete interval of rotation is determined, based upon measurements of one or more magnetic pole position sensors for magnetic pole location. In another embodiment, a time interval between two poles is averaged over one or more rotational periods, and the average time interval is used to determine the moving average speed. Computation of the moving average speed reduces errors in speed measurements due to pole misalignment and may provide for smaller control adjustment times for controlling motor speed variability. In one embodiment, the speed measurement system includes a multi-pole rotor, and a controller having a capture timer and a buffer.
    Type: Grant
    Filed: December 30, 2002
    Date of Patent: March 13, 2007
    Assignee: Ballard Power Systems Corporation
    Inventors: Kerry E. Grand, Richard J. Hampo, Yifan Zhao
  • Patent number: 7024290
    Abstract: A system and method for actively damping driveline oscillations in a motor vehicle having a traction motor to drive a vehicle's drive wheels and an antilock brake system (ABS). A traction motor controller controls a torque output signal of the motor to effectively to dampen driveline oscillations during an ABS operation. A proportional, a proportional derivative, or a derivative controller may be used to generate the torque output signal based on at least one of motor speed, an average of the drive wheel speeds, a difference in the two speeds, a motor angular acceleration, an average wheel angular acceleration, and a difference in the angular accelerations. Motor speed signals and average drive wheel speed signals may be filtered to eliminate high frequency components of each speed signal. Additionally, amplitude of the torque output signal may be limited within a positive upper and a negative lower active motor damping limit.
    Type: Grant
    Filed: July 30, 2004
    Date of Patent: April 4, 2006
    Assignee: Ford Global Technologies, LLC
    Inventors: Yifan Zhao, Michael Schneider, Dale Crombez
  • Publication number: 20060025905
    Abstract: A system and method for actively damping driveline oscillations in a motor vehicle having a traction motor to drive a vehicle's drive wheels and an antilock brake system (ABS). A traction motor controller controls a torque output signal of the motor to effectively to dampen driveline oscillations during an ABS operation. A proportional, a proportional derivative, or a derivative controller may be used to generate the torque output signal based on at least one of motor speed, an average of the drive wheel speeds, a difference in the two speeds, a motor angular acceleration, an average wheel angular acceleration, and a difference in the angular accelerations. Motor speed signals and average drive wheel speed signals may be filtered to eliminate high frequency components of each speed signal. Additionally, amplitude of the torque output signal may be limited within a positive upper and a negative lower active motor damping limit.
    Type: Application
    Filed: July 30, 2004
    Publication date: February 2, 2006
    Inventors: Yifan Zhao, Michael Schneider, Dale Crombez
  • Patent number: 6700342
    Abstract: A control system for a permanent magnet motor having low-resolution speed measurement is taught. The control system is comprised of a speed regulator, voltage regulator and current regulator. The speed regulator uses a speed command and a measured speed for calculating a desired motor voltage; the voltage regulator uses a voltage command and an applied motor voltage for calculating a motor current command; and the current regulator uses a current command and a motor phase current for calculating a desired motor voltage for use by said voltage regulator; thereby providing a low resolution speed measurement to be used in a high performance application.
    Type: Grant
    Filed: July 29, 2002
    Date of Patent: March 2, 2004
    Assignee: Ballard Power Systems Corporation
    Inventors: Richard J. Hampo, Yifan Zhao
  • Publication number: 20030164692
    Abstract: A method and apparatus for improving the speed measurement quality in systems having multi-pole machines is taught. The method compensates for pole misalignment by moving average techniques.
    Type: Application
    Filed: December 30, 2002
    Publication date: September 4, 2003
    Applicant: Ballard Power Systems Corporation
    Inventors: Kerry E. Grand, Richard J. Hampo, Yifan Zhao
  • Publication number: 20030030395
    Abstract: A control system for a permanent magnet motor having low-resolution speed measurement is taught. The control system is comprised of a speed regulator, voltage regulator and current regulator. The speed regulator uses a speed command and a measured speed for calculating a desired motor voltage; the voltage regulator uses a voltage command and an applied motor voltage for calculating a motor current command; and the current regulator uses a current command and a motor phase current for calculating a desired motor voltage for use by said voltage regulator; thereby providing a low resolution speed measurement to be used in a high performance application.
    Type: Application
    Filed: July 29, 2002
    Publication date: February 13, 2003
    Applicant: Ballard Power Systems Corporation
    Inventors: Richard J. Hampo, Yifan Zhao
  • Patent number: 6366049
    Abstract: A speed controller circuit for a motor including a ramp function generator having a first input connected to a source of a speed demand signal and a second input connected to a ramp step signal. The ramp function generator develops a frequency ramp that has a slope is initiated by the speed demand signal which is adjusted in response to the ramp step signal. The ramp function generator also provides a frequency signal wherein the ramp function increases or decreases the frequency according to the speed demand. A V/F circuit to the ramp function generator and a space vector modulation circuit are connected to the V/F circuit. The output of the space vector modulation circuit is applied through power switching devices to the motor for speed control. A PI controller circuit is connected to a motor current feedback signal and to a maximum current signal, which provides the current limit of the control system.
    Type: Grant
    Filed: May 10, 2000
    Date of Patent: April 2, 2002
    Assignee: Ecostar Electric Drive Systems L.L.C.
    Inventors: Li Chen, Richard Joseph Hampo, Yifan Zhao
  • Patent number: 6058031
    Abstract: A high power motor drive converter includes: a five level hybrid NPC output power conversion stage including three NPC phase bridges having switches and coupled in a wye configuration through a converter neutral point, each NPC phase bridge receiving power on a respective direct current bus; three isolated split series-connected DC capacitor banks each coupled in parallel to a respective one of the three NPC phase bridges; and a controller for selecting switch positions with active control of neutral voltages. The controller is adapted to select switch positions using feedforward sine-triangle modulation with third harmonic injection, zero sequence injection, and/or discontinuous modulation injection.
    Type: Grant
    Filed: June 30, 1998
    Date of Patent: May 2, 2000
    Assignee: General Electric Company
    Inventors: James Patrick Lyons, Vlatko Vlatkovic, Paul Martin Espelage, Albert Andreas Maria Esser, Yifan Zhao, Fei Fred Wang, Sr.