Patents by Inventor Shifang Li

Shifang Li 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: 20170234199
    Abstract: An internal combustion engine fluidly coupled to an exhaust aftertreatment system includes a particulate filter device, a first selective catalytic reduction device disposed upstream relative to a second selective catalytic reduction device, and an injection system disposed to inject a reductant into the exhaust gas feedstream upstream relative to the first selective catalytic reduction device. A method for controlling the internal combustion engine includes monitoring engine operation, and determining an amount of particulate matter stored on the particulate filter based thereon. An amount of reductant stored on the second selective catalytic reduction device and operating conditions associated with the exhaust aftertreatment system are also determined.
    Type: Application
    Filed: February 11, 2016
    Publication date: August 17, 2017
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Min Sun, Shifang Li, Giuseppe Mazzara Bologna, Joshua Clifford Bedford
  • Patent number: 9709386
    Abstract: Disclosed are methods and apparatus for measuring a characteristics of a through-silicon via (TSV) structure. A beam profile reflectivity (BPR) tool is used to move to a first xy position having a TSV structure. The BPR tool is then used to obtain an optimum focus of at the first xy position by adjusting the z position to a first optimum z position for obtaining measurements at the first xy position. Via the BPR tool, reflectivity measurements for a plurality of angles of incidence are obtained at the first xy position. One or more film thicknesses for the TSV structure are determined based on the reflectivity measurements. A z position can also be recorded and used to determine a height of such TSV structure, as well as one or more adjacent xy positions.
    Type: Grant
    Filed: April 5, 2016
    Date of Patent: July 18, 2017
    Assignee: KLA-Tencor Corporation
    Inventors: Lena Nicolaides, Timothy Goodwin, Raul V. Tan, Shifang Li
  • Patent number: 9709543
    Abstract: An internal combustion engine is described in conjunction with a method for dynamically determining a mass flow rate of nitrogen oxides (NOx) for its exhaust gas feedstream. The method includes determining a present engine operating point and determining a reference NOx content for a reference engine operating point. A combustion chemical reaction rate is determined based upon the present engine operating point and the reference engine operating point. A NOx content in the exhaust gas feedstream is dynamically determined during operation of the internal combustion engine based upon the reference NOx content, the combustion chemical reaction rate and a combustion mixing rate constant.
    Type: Grant
    Filed: May 6, 2015
    Date of Patent: July 18, 2017
    Assignee: GM Global Technology Operations LLC
    Inventors: Min Sun, Shifang Li
  • Publication number: 20170167347
    Abstract: A system according to the present disclosure includes a model predictive control (MPC) module and an actuator module. The MPC module generates a set of possible target values for an actuator of an engine and predicts an operating parameter for the set of possible target values. The predicted operating parameter includes an emission level and/or an operating parameter of an exhaust system. The MPC module determines a cost for the set of possible target values and selects the set of possible target values from multiple sets of possible target values based on the cost. The MPC module determines whether the predicted operating parameter for the selected set satisfies a constraint and sets target values to the possible target values of the selected set when the predicted operating parameter satisfies the constraint. The actuator module controls an actuator of an engine based on at least one of the target values.
    Type: Application
    Filed: December 10, 2015
    Publication date: June 15, 2017
    Inventors: Min SUN, Shifang LI, Francesco CIANFLONE, Paolo NALBONE
  • Publication number: 20170168466
    Abstract: A system includes a target generating module, a model predictive control (MPC) module, and an actuator module. The target generating module generates a target value for an actuator of an engine. The MPC module generates a set of possible adjustments to the target value and predicts an operating parameter for the set of possible adjustments. The predicted operating parameter includes an emission level and/or an operating parameter of an exhaust system. The MPC module determines a cost for the set of possible adjustments and selects the set of possible adjustments from multiple sets of possible adjustments based on the cost. The MPC module determines whether the predicted operating parameter for the selected set satisfies a constraint and adjusts the target value using the possible adjustments of the selected set when the predicted operating parameter satisfies the constraint. The actuator module controls the actuator based on the target value as adjusted.
    Type: Application
    Filed: December 10, 2015
    Publication date: June 15, 2017
    Inventors: Min SUN, Shifang LI, Giuseppe Mazzara BOLOGNA, Francesco CIANFLONE, Paolo NALBONE
  • Patent number: 9658150
    Abstract: A system determines a value, such as a thickness, surface roughness, material concentration, and/or critical dimension, of a layer on a wafer based on normalized signals and reflected total intensities. A light source directs a beam at a surface of the wafer. A sensor receives the reflected beam and provides at least a pair of polarization channels. The signals from the polarization channels are received by a controller, which normalizes a difference between a pair of the signals to generate the normalized result. The value of the wafer is determined through analyzing the signal with a modeling of the system.
    Type: Grant
    Filed: January 7, 2016
    Date of Patent: May 23, 2017
    Assignee: KLA-Tencor Corporation
    Inventors: Shifang Li, Youxian Wen
  • Publication number: 20170138237
    Abstract: An exhaust system for a lean-burn internal combustion engine is described, and includes an injection system for injecting reductant into an exhaust gas feedstream upstream of a selective catalytic reduction device (SCR). A control method for controlling the injection system includes determining an upstream NOx gas concentration upstream of the SCR device, determining a measured downstream NOx gas concentration based upon a signal output from a sensor configured to monitor NOx gas concentration downstream of the SCR device, and determining an estimated downstream NOx gas concentration based upon an executable model. A first correlation between the upstream NOx gas concentration and the measured downstream NOx gas concentration is determined, and a second correlation between the upstream NOx gas concentration and the estimated downstream NOx gas concentration is determined. The reductant injection is controlled based upon the first and second correlations.
    Type: Application
    Filed: November 12, 2015
    Publication date: May 18, 2017
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Shifang Li, Min Sun, Kevin Andrew Gady, Raffaello Ardanese, Giuseppe Mazzara Bologna
  • Patent number: 9644543
    Abstract: An engine assembly includes an intake manifold and a manifold absolute pressure sensor configured to generate a current measured manifold absolute pressure (MAPM) signal for the intake manifold. The assembly includes a throttle valve adjustable to control airflow to the intake manifold and a throttle position sensor configured to generate a current measured throttle position (TPM) signal. A controller is operatively connected to the throttle valve and the manifold absolute pressure sensor and has a processor and tangible, non-transitory memory on which is recorded instructions for executing a method for determining a predicted manifold absolute pressure (MAPP). Execution of the instructions by the processor causes the controller to determine the predicted manifold absolute pressure (MAPP) based at least partially on a predicted throttle flow (TFP) and the current measured manifold absolute pressure (MAPM) signal.
    Type: Grant
    Filed: February 17, 2015
    Date of Patent: May 9, 2017
    Assignee: GM Global Technology Operations LLC
    Inventors: Yiran Hu, Ibrahim Haskara, Shifang Li, Sai S. V. Rajagopalan, Steven E Muldoon, Chen-Fang Chang
  • Patent number: 9640449
    Abstract: Photoreflectance spectroscopy is used to measure strain at or near the edge of a wafer in a production process. The strain measurement is used to anticipate defects and make prospective corrections in later stages of the production process. Strain measurements are used to associate various production steps with defects to enhance later production processes.
    Type: Grant
    Filed: April 16, 2015
    Date of Patent: May 2, 2017
    Assignee: KLA-Tencor Corporation
    Inventors: Timothy Goodwin, Lena Nicolaides, Mohan Mahadevan, Paul Horn, Shifang Li
  • Patent number: 9625937
    Abstract: A method for improving computation efficiency for diffraction signals in optical metrology is described. The method includes simulating a set of diffraction orders for a three-dimensional structure. The diffraction orders within the set of diffraction orders are then prioritized. The set of diffraction orders is truncated to provide a truncated set of diffraction orders based on the prioritizing. Finally, a simulated spectrum is provided based on the truncated set of diffraction orders.
    Type: Grant
    Filed: August 18, 2008
    Date of Patent: April 18, 2017
    Assignee: KLA-Tencor Corporation
    Inventors: Joerg Bischoff, Shifang Li, Weidong Yang, Hanyou Chu
  • Publication number: 20170082424
    Abstract: A system includes a first beam splitter, a second beam splitter, and a mirror. The second beam splitter can produce two lines of light, which are received by at least one sensor. The two lines of light have different focal heights on the wafer. A distance between the second beam splitter and the mirror can be configured to change a focal height on the wafer. A height of an illuminated region on a surface of the wafer relative to a normal surface of the wafer can be determined using the two lines of light.
    Type: Application
    Filed: September 19, 2016
    Publication date: March 23, 2017
    Inventor: Shifang Li
  • Publication number: 20170067732
    Abstract: A system that can be used for used for semiconductor height inspection and metrology includes a complementary plate that is used with a beam splitter to create desired astigmatism and to remove chromatic aberration. Simultaneous optimization of lateral resolution and sensitivity can be enabled. The complementary plate can be made of the same material and have the same thickness as the beam splitter.
    Type: Application
    Filed: September 2, 2016
    Publication date: March 9, 2017
    Inventor: Shifang Li
  • Publication number: 20170030243
    Abstract: A method for controlling a selective catalytic reduction device in an exhaust aftertreatment system of a vehicle includes monitoring vehicle connectivity information, and controlling ammonia storage in the selective catalytic reduction device based on the monitored vehicle connectivity information. Vehicle connectivity information is used to predict vehicle operating conditions along an estimated path of vehicle travel. The predicted vehicle operating conditions are used to predict profiles for vehicle exhaust gas parameters. Predicted profiles for exhaust gas parameters are used in determining ammonia storage setpoints for the selective catalytic reduction device. The ammonia storage setpoints are use in regulating an amount of ammonia producing dosing agent injected into the exhaust aftertreatment system, thereby controlling ammonia storage in the selective catalytic reduction device.
    Type: Application
    Filed: July 28, 2015
    Publication date: February 2, 2017
    Inventors: SHIFANG LI, MIN SUN
  • Publication number: 20160377412
    Abstract: Disclosed are apparatus and methods for determining height of a semiconductor structure. The system includes an illumination module for directing one or more source lines or points towards a specimen having multiple surfaces at different relative heights and a collection module for detecting light reflected from the surfaces. The collection module contains at least two detectors with one slit or pinhole in front of each detector that that are positioned to receive light reflected from one of the surfaces. A first detector receives reflected light from a slit or pinhole that is positioned before a focal point, and a second detector receive reflected light from a slit or pinhole that is positioned after the focal point so that the first and second detector receive light having different intensity values unless the surface is at an optimum focus. The system includes a processor system for determining a height based on the detected light received by the detectors from two of the surfaces.
    Type: Application
    Filed: June 24, 2016
    Publication date: December 29, 2016
    Applicant: KLA-Tencor Corporation
    Inventors: Shifang Li, Guoheng Zhao
  • Patent number: 9494488
    Abstract: A method to determine a rotational position of a phaser for variable phasing system including a low-resolution rotational position sensing system includes estimating a rotational position of the phaser based upon a time interval between occurrence of a measured position of the phaser and a present periodic timepoint, a commanded position of the phaser, said measured position of the phaser, and a time constant of the variable phasing system when the occurrence of the measured position of the phaser is subsequent to a preceding periodic timepoint occurring at a set time interval prior to the present periodic timepoint.
    Type: Grant
    Filed: July 22, 2014
    Date of Patent: November 15, 2016
    Assignee: GM Global Technology Operations LLC
    Inventors: Shifang Li, Jyh-Shin Chen
  • Publication number: 20160327534
    Abstract: An internal combustion engine is described in conjunction with a method for dynamically determining a mass flow rate of nitrogen oxides (NOx) for its exhaust gas feedstream. The method includes determining a present engine operating point and determining a reference NOx content for a reference engine operating point. A combustion chemical reaction rate is determined based upon the present engine operating point and the reference engine operating point. A NOx content in the exhaust gas feedstream is dynamically determined during operation of the internal combustion engine based upon the reference NOx content, the combustion chemical reaction rate and a combustion mixing rate constant.
    Type: Application
    Filed: May 6, 2015
    Publication date: November 10, 2016
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Min Sun, Shifang Li
  • Patent number: 9482164
    Abstract: A system includes a turbocharged engine, sensors, and a controller. The engine includes an engine intake manifold, air intake manifold, a compressor, a first aftercooler device, a throttle that admits cooled compressed air to the engine intake manifold, and cylinders. The sensors determine engine status signals and include a first manifold pressure (MAP) sensor positioned with respect to the first aftercooler device, a second MAP sensor positioned with respect to the engine intake manifold, a mass airflow (MAF) sensor positioned in the air intake manifold, a first manifold temperature (MAT) sensor positioned in the engine intake manifold, and a second MAT sensor positioned between the first aftercooler device and the throttle. The controller executes a method to calculate a cylinder air charge using an oxygen level of post-combustion gasses and the engine status signals, and controls an operation of the engine using the calculated air charge via engine control signals.
    Type: Grant
    Filed: March 30, 2015
    Date of Patent: November 1, 2016
    Assignee: GM Global Technology Operations LLC
    Inventors: Hossein Javaherian, Shifang Li, Yiran Hu, Jun-Mo Kang, Chen-Fang Chang
  • Publication number: 20160290256
    Abstract: A system includes a turbocharged engine, sensors, and a controller. The engine includes an engine intake manifold, air intake manifold, a compressor, a first aftercooler device, a throttle that admits cooled compressed air to the engine intake manifold, and cylinders. The sensors determine engine status signals and include a first manifold pressure (MAP) sensor positioned with respect to the first aftercooler device, a second MAP sensor positioned with respect to the engine intake manifold, a mass airflow (MAF) sensor positioned in the air intake manifold, a first manifold temperature (MAT) sensor positioned in the engine intake manifold, and a second MAT sensor positioned between the first aftercooler device and the throttle. The controller executes a method to calculate a cylinder air charge using an oxygen level of post-combustion gasses and the engine status signals, and controls an operation of the engine using the calculated air charge via engine control signals.
    Type: Application
    Filed: March 30, 2015
    Publication date: October 6, 2016
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Hossein Javaherian, Shifang Li, Yiran Hu, Jun-Mo Kang, Chen-Fang Chang
  • Publication number: 20160275671
    Abstract: Systems and methods for enhancing inspection sensitivity to detect defects in wafers using an inspection tool are disclosed. A plurality of light emitting diodes illuminate at least a portion of a wafer and capture a set of grayscale images. A residual signal is determined in each image of the grayscale image set and the residual signal is subtracted from each image of the grayscale image set. Defects are identified based on the subtracted grayscale image set. Models of the inspection tool and wafer may be built and refined in some embodiments of the disclosed systems and methods.
    Type: Application
    Filed: March 11, 2016
    Publication date: September 22, 2016
    Inventors: Shifang Li, Youxian Wen, Sven Schwitalla, Prashant Aji, Lena Nicolaides
  • Publication number: 20160237940
    Abstract: An engine system includes a mass air flow sensor and a manifold absolute pressure sensor configured to provide a real-time MAP signal during an event. The mass air flow sensor is configured to generate a set of mass air flow readings based on an airflow through the mass air flow sensor during the event. The set of mass air flow readings have a maximum value and a minimum value. A controller is configured to execute a method for detecting reversion in the air flow. If the rate of change in the real-time MAP signal is less than the predetermined transient threshold value (T0), the method includes setting a delta factor (D) as the difference between the maximum value and the minimum value. Reversion is detected based at least partially on a magnitude of the delta factor (D).
    Type: Application
    Filed: February 17, 2015
    Publication date: August 18, 2016
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Yiran Hu, Shifang Li, Chen-Fang Chang