Patents by Inventor Qing-San Xiang

Qing-San Xiang 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: 20070098298
    Abstract: Methods, apparatus, computer-readable media and signals for imaging are disclosed. A method includes performing a phasor iteration process to identify a phase error phasor associated with: a first input image data set representing a first image of an object having at least a first component and a second component, and a second input image data set representing a second image of the object. The method further includes generating a first output image data set representing an image of the first component of the object, in response to the first and second input image data sets and the phase error phasor. The first and second components of the object may include first and second chemical components.
    Type: Application
    Filed: November 2, 2006
    Publication date: May 3, 2007
    Inventor: Qing-San Xiang
  • Publication number: 20060124036
    Abstract: A novel concept of ergodynamic desktops with slowly varying configurations for ergonomic purposes is provided. Very slow motions are incorporated into the design of desktops, usually used by computer users. The introduced motion is at such a slow pace that it is hardly noticeable, similar to the adiabatic motions of hour or minute hands on a clock. Users of the desktops are therefore induced to adjust their body posture accordingly in a gradual and healthy manner, while still continuing to perform their normal activities without interruption. These desktop designs allow a natural and effortless combination of normal life and exercise. When used in a working environment, they will be useful to improve the health and to enhance the efficiency of workers.
    Type: Application
    Filed: October 28, 2005
    Publication date: June 15, 2006
    Inventors: Bing Xu, Qing-san Xiang
  • Patent number: 6150815
    Abstract: A method of correcting for magnetic field inhomogeneity caused by various factors, such as implanted metal and air/tissue interfaces, in magnetic resonance imaging (MRI) is provided. Geometric distortion due to inhomogeneity in a static magnetic field B.sub.0 is corrected for by addition of a compensation gradient. The compensation gradient is applied in the slice selection direction Z, has a timing substantially identical to the standard frequency encoding gradient G.sub.x, and has an amplitude identical to the slice selection gradient G.sub.z that is applied during the initial RF excitation. Inhomogeneity in an RF field B.sub.1 is compensated for by utilizing an RF coil that is large enough in size as compared with a metal implant to make the volumetric percentage of the metal in the coil insignificant. Inhomogeneity in a gradient field G=(G.sub.x, G.sub.y, G.sub.z) is corrected for by a treatment of the most significant error factor G.sub.z that causes slice thickness error.
    Type: Grant
    Filed: April 9, 1998
    Date of Patent: November 21, 2000
    Assignee: The University of British Columbia
    Inventors: Dennis Lyle Janzen, Douglas George Connell, Alexander Lloyd MacKay, Qing-San Xiang
  • Patent number: 6091243
    Abstract: A method acquires three complex images, wherein their respective phase differences between water and fat components are .alpha..sub.0, .alpha..sub.0 +.alpha., and .alpha..sub.0 +2.alpha., respectively. The method obtains from these three complex images two possible solution sets for water and fat images. For pixels with both water and fat components, one correct solution set is selected using a binary choice based on the relative Larmor frequencies of water and fat. If a pixel contains only one component, a known statistical bias is applied to identify the component and, thus, the pixel. To correct misidentified pixels, various filters may be applied to all the pixels. The water and fat solutions obtained from the three complex images are used to produce separate images of water and fat. Second pass solutions of water and fat with improved signal-to-noise ratio can be obtained by either averaging or a least square error method.
    Type: Grant
    Filed: November 13, 1998
    Date of Patent: July 18, 2000
    Assignee: The University of British Columbia
    Inventors: Qing-San Xiang, Li An
  • Patent number: 5994902
    Abstract: Chemical shift imaging with spectrum modeling (CSISM) models the general chemical shift spectrum as a system with N distinct peaks with known resonant frequencies and unknown amplitudes. Based on the N peak spectrum model, a set of nonlinear complex equations is set up that contains N+1 unknowns of two kdnds: the magnitudes of the N peaks, and a phasor map caused by main magnetic field inhomogeneity. Using these equations, the timing parameters for shifting the 180.degree. RF refocusing pulses for acquiring spin-echo images are optimally chosen. Corresponding timing parameters for other pulse sequences can also be optimized similarly. Using the chosen timing parameters, a plurality of images are acquired. Next, acquired image data are automatically processed to solve the complex linear equations. First, the phasor map is found by fitting various phasor map values over a small number of pixels, or "seeds", that are picked sparsely in a field of view.
    Type: Grant
    Filed: April 9, 1998
    Date of Patent: November 30, 1999
    Assignee: The University of British Columbia
    Inventors: Qing-San Xiang, Li An
  • Patent number: 5363043
    Abstract: A method for producing dynamic images from a ghosted MR image is disclosed. The method includes acquiring an image data set including a time averaged image component and a ghost component and processing these components to produce a dynamic image. A motion monitoring system is not required as in conventional cine magnetic resonance imaging.
    Type: Grant
    Filed: February 9, 1993
    Date of Patent: November 8, 1994
    Assignee: Sunnybrook Health Science Center
    Inventors: Qing-San Xiang, Ross M. Henkelman
  • Patent number: 5363044
    Abstract: A method for manipulating motion ghosts is disclosed. The method includes acquiring two image data sets, each including a time averaged image component and a ghost component and processing these components to separate the ghosts from the desired image and further using the ghost information to produce a dynamic image. Motion monitoring systems are not required. Improved scan times and noise control are allowed over previous methods.
    Type: Grant
    Filed: February 9, 1993
    Date of Patent: November 8, 1994
    Assignee: Sunnybrook Health Science Center
    Inventors: Qing-San Xiang, Ross M. Henkelman
  • Patent number: 5233302
    Abstract: An NMR imaging system performs a scan to acquire three sets of data which are Fourier transformed to produce three image data arrays. A corrected image data array is calculated from corresponding elements in the three acquired image data arrays. Image artifacts which cause ghosts in the reconstructed image are masked from the corrected image data by the calculations.
    Type: Grant
    Filed: June 21, 1991
    Date of Patent: August 3, 1993
    Assignee: General Electric Company
    Inventors: Qing-San Xiang, Ross M. Henkelman