Patents by Inventor Liukang Xu
Liukang Xu 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).
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Patent number: 11460480Abstract: Systems and methods for measuring turbulent gas flux using high-speed vertical wind speed measurements (e.g., on the order of 5-10 Hz or more frequently) and low-speed gas content measurements (e.g., on the order of 5 Hz or less frequently), without the need for the sophisticated and expensive high-speed hardware to separate gas samples (e.g., into accumulation bags) according to updrafts and downdrafts. A time series of high-speed vertical wind speed data is used as a guide to distinguish between updrafts and downdrafts. When vertical wind speed is upward (updraft), the low-speed gas content is recorded into a data structure in one location, or marked with one flag. When vertical wind speed is downward (downdraft), the low-speed gas content is recorded into a different location, or marked with a different flag. Eddy Accumulation or Relaxed Eddy Accumulation computations can be performed using the stored gas content data to determine gas flux.Type: GrantFiled: August 8, 2018Date of Patent: October 4, 2022Assignee: Li-Cor, Inc.Inventors: George G. Burba, Dayle McDermitt, Xiaomao Lin, Liukang Xu, Dave Johnson
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Publication number: 20180372770Abstract: Systems and methods for measuring turbulent gas flux using high-speed vertical wind speed measurements (e.g., on the order of 5-10 Hz or more frequently) and low-speed gas content measurements (e.g., on the order of 5 Hz or less frequently), without the need for the sophisticated and expensive high-speed hardware to separate gas samples (e.g., into accumulation bags) according to updrafts and downdrafts. A time series of high-speed vertical wind speed data is used as a guide to distinguish between updrafts and downdrafts. When vertical wind speed is upward (updraft), the low-speed gas content is recorded into a data structure in one location, or marked with one flag. When vertical wind speed is downward (downdraft), the low-speed gas content is recorded into a different location, or marked with a different flag. Eddy Accumulation or Relaxed Eddy Accumulation computations can be performed using the stored gas content data to determine gas flux.Type: ApplicationFiled: August 8, 2018Publication date: December 27, 2018Inventors: George G. Burba, Dayle McDermitt, Xiaomao Lin, Liukang Xu, Dave Johnson
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Patent number: 10060942Abstract: Systems and methods for measuring turbulent gas flux using high-speed vertical wind speed measurements (e.g., on the order of 5-10 Hz or more frequently) and low-speed gas content measurements (e.g., on the order of 5 Hz or less frequently), without the need for the sophisticated and expensive high-speed hardware to separate gas samples (e.g., into accumulation bags) according to updrafts and downdrafts. A time series of high-speed vertical wind speed data is used as a guide to distinguish between updrafts and downdrafts. When vertical wind speed is upward (updraft), the low-speed gas content is recorded into a data structure in one location, or marked with one flag. When vertical wind speed is downward (downdraft), the low-speed gas content is recorded into a different location, or marked with a different flag. Eddy Accumulation or Relaxed Eddy Accumulation computations can be performed using the stored gas content data to determine gas flux.Type: GrantFiled: April 6, 2012Date of Patent: August 28, 2018Assignee: Li-Cor, Inc.Inventors: George G. Burba, Dayle McDermitt, Xiaomao Lin, Liukang Xu, Dave Johnson
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Publication number: 20130268208Abstract: Systems and methods for measuring turbulent gas flux using high-speed vertical wind speed measurements (e.g., on the order of 5-10 Hz or more frequently) and low-speed gas content measurements (e.g., on the order of 5 Hz or less frequently), without the need for the sophisticated and expensive high-speed hardware to separate gas samples (e.g., into accumulation bags) according to updrafts and downdrafts. A time series of high-speed vertical wind speed data is used as a guide to distinguish between updrafts and downdrafts. When vertical wind speed is upward (updraft), the low-speed gas content is recorded into a data structure in one location, or marked with one flag. When vertical wind speed is downward (downdraft), the low-speed gas content is recorded into a different location, or marked with a different flag. Eddy Accumulation or Relaxed Eddy Accumulation computations can be performed using the stored gas content data to determine gas flux.Type: ApplicationFiled: April 6, 2012Publication date: October 10, 2013Applicant: LI-COR, Inc.Inventors: George G. Burba, Dayle McDermitt, Xiaomao Lin, Liukang Xu, Dave Johnson
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Patent number: 8433525Abstract: A system and method to obtain correct gas density and flux measurements using (i) gas analyzer (open-path, or closed-path gas analyzers with short intake tube, or any combination of the two); (ii) fast temperature or sensible heat flux measurement device (such as, fine-wire thermocouple, sonic anemometer, or any other device providing fast accurate gas temperature measurements); (iii) fast air water content or latent heat flux measurement device (such as, hygrometer, NDIR analyzer, any other device providing fast accurate gas water content measurements); (iv) vertical wind or sampling device (such as sonic anemometer, scintillometer, or fast solenoid valve, etc.) and (v) algorithms in accordance with the present invention to compute the corrected gas flux, compensated for T-P effects. In case when water factor in T-P effects is negligible, the fast air water content or latent heat flux measurement device (item iii in last paragraph) can be excluded.Type: GrantFiled: April 12, 2011Date of Patent: April 30, 2013Assignee: LI-COR, Inc.Inventors: George Burba, Dayle McDermitt, Anatoly Komissarov, Tyler G. Anderson, Liukang Xu, Bradley A. Riensche
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Publication number: 20110270534Abstract: Disclosed embodiments of the present invention provide means to obtain correct gas density and flux measurements using (i) gas analyzer (open-path, or closed-path gas analyzers with short intake tube, for example 1 m long, or any combination of the two); (ii) fast temperature or sensible heat flux measurement device (such as, fine-wire thermocouple, sonic anemometer, or any other device providing fast accurate gas temperature measurements); (iii) fast air water content or latent heat flux measurement device (such as, hygrometer, NDIR analyzer, any other device providing fast accurate gas water content measurements); (iv) vertical wind or sampling device (such as sonic anemometer, scintillometer, or fast solenoid valve, etc.) and (v) algorithms in accordance with the present invention to compute the corrected gas flux, compensated for T-P effects.Type: ApplicationFiled: April 12, 2011Publication date: November 3, 2011Applicant: LI-COR, Inc.Inventors: George Burba, Dayle McDermitt, Anatoly Komissarov, Tyler G. Anderson, Liukang Xu, Bradley A. Riensche
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Patent number: 7953558Abstract: Disclosed embodiments of the present invention provide means to obtain correct gas density and flux measurements using (i) gas analyzer (open-path, or closed-path gas analyzers with short intake tube, for example 1 m long, or any combination of the two); (ii) fast temperature or sensible heat flux measurement device (such as, fine-wire thermocouple, sonic anemometer, or any other device providing fast accurate gas temperature measurements); (iii) fast air water content or latent heat flux measurement device (such as, hygrometer, NDIR analyzer, any other device providing fast accurate gas water content measurements); (iv) vertical wind or sampling device (such as sonic anemometer, scintillometer, or fast solenoid valve, etc.) and (v) algorithms in accordance with the present invention to compute the corrected gas flux, compensated for T-P effects.Type: GrantFiled: September 3, 2009Date of Patent: May 31, 2011Assignee: Li-Cor, Inc.Inventors: George Burba, Dayle McDermitt, Anatoly Komissarov, Tyler G. Anderson, Liukang Xu, Bradley A. Riensche
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Publication number: 20110061442Abstract: A method and apparatus are provided for maintaining pressure inside a closed chamber equal to the changing outside pressure, detecting leaks in the plumbing (i.e., air handling system) of a trace gas flux measurement system, and estimating the kinetic volume, e.g., of such a system.Type: ApplicationFiled: November 19, 2010Publication date: March 17, 2011Applicant: LI-COR, Inc.Inventors: Michael D. Furtaw, Dayle K. McDermitt, Liukang Xu
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Publication number: 20110054803Abstract: Disclosed embodiments of the present invention provide means to obtain correct gas density and flux measurements using (i) gas analyzer (open-path, or closed-path gas analyzers with short intake tube, for example 1 m long, or any combination of the two); (ii) fast temperature or sensible heat flux measurement device (such as, fine-wire thermocouple, sonic anemometer, or any other device providing fast accurate gas temperature measurements); (iii) fast air water content or latent heat flux measurement device (such as, hygrometer, NDIR analyzer, any other device providing fast accurate gas water content measurements); (iv) vertical wind or sampling device (such as sonic anemometer, scintillometer, or fast solenoid valve, etc.) and (v) algorithms in accordance with the present invention to compute the corrected gas flux, compensated for T-P effects.Type: ApplicationFiled: September 3, 2009Publication date: March 3, 2011Applicant: LI-COR, Inc.Inventors: George Burba, Dayle McDermitt, Anatoly Komissarov, Tyler G. Anderson, Liukang Xu, Bradley A. Riensche
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Patent number: 7856899Abstract: A method and apparatus are provided for maintaining pressure inside a closed chamber equal to the changing outside pressure, detecting leaks in the plumbing (i.e., air handling system) of a trace gas flux measurement system, and estimating the kinetic volume, e.g., of such a system.Type: GrantFiled: February 13, 2009Date of Patent: December 28, 2010Assignee: LI-COR, Inc.Inventors: Michael D. Furtaw, Dayle K. McDermitt, Liukang Xu
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Patent number: 7748253Abstract: A method and apparatus are provided for maintaining pressure inside a closed chamber equal to the changing outside pressure, detecting leaks in the plumbing (i.e., air handling system) of a trace gas flux measurement system, and estimating the kinetic volume, e.g., of such a system.Type: GrantFiled: February 22, 2005Date of Patent: July 6, 2010Assignee: LI-COR, Inc.Inventors: Michael D. Furtaw, Liukang Xu
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Publication number: 20090139307Abstract: A method and apparatus are provided for maintaining pressure inside a closed chamber equal to the changing outside pressure, detecting leaks in the plumbing (i.e., air handling system) of a trace gas flux measurement system, and estimating the kinetic volume, e.g., of such a system.Type: ApplicationFiled: February 13, 2009Publication date: June 4, 2009Applicant: LI-COR, Inc.Inventors: Michael D. Furtaw, Dayle K. McDermitt, Liukang Xu
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Publication number: 20060117840Abstract: A method and apparatus are provided for maintaining pressure inside a closed chamber equal to the changing outside pressure, detecting leaks in the plumbing (i.e., air handling system) of a trace gas flux measurement system, and estimating the kinetic volume, e.g., of such a system.Type: ApplicationFiled: February 22, 2005Publication date: June 8, 2006Inventors: Michael Furtaw, Dayle McDermitt, Liukang Xu