Patents by Inventor Chengjun Julian Chen

Chengjun Julian Chen 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: 9890314
    Abstract: The present invention generally relates to solar water heaters, in particular to solar water heaters using glass vacuum tubes as both solar energy collector and thermal energy storage device, without a hot water storage tank. To improve the efficiency of thermal energy storage, a novel medium for thermal energy storage is disclosed, which utilizes the heat of solution of aluminum sulphate, comprising water and 40% to 47% of Al2(SO4)3. The working temperature range of such energy storage medium is between 50° C. and 100° C. The energy storage medium is contained in plastic capsules, submerged in water and placed in glass vacuum tubes.
    Type: Grant
    Filed: November 24, 2014
    Date of Patent: February 13, 2018
    Assignee: The Trustees of Columbia University in the City of New York
    Inventor: Chengjun Julian Chen
  • Publication number: 20160146509
    Abstract: The present invention generally relates to solar water heaters, in particular to solar water heaters using glass vacuum tubes as both solar energy collector and thermal energy storage device, without a hot water storage tank. To improve the efficiency of thermal energy storage, a novel medium for thermal energy storage is disclosed, which utilizes the heat of solution of aluminum sulphate, comprising water and 40% to 47% of Al2(SO4)3. The working temperature range of such energy storage medium is between 50° C. and 100° C. The energy storage medium is contained in plastic capsules, submerged in water and placed in glass vacuum tubes.
    Type: Application
    Filed: November 24, 2014
    Publication date: May 26, 2016
    Inventor: Chengjun Julian Chen
  • Publication number: 20150262587
    Abstract: A pitch-synchronous method and system for speech coding using timbre vectors is disclosed. On the encoder side, speech signal is segmented into pitch-synchronous frames without overlap, then converted into a pitch-synchronous amplitude spectrum using FFT. Using Laguerre functions, the amplitude spectrum is transformed into a timbre vector. Using vector quantization, each timbre vector is converted to a timbre index based on a timbre codebook. The intensity and pitch are also converted into indices respectively using scalar quantization. Those indices are transmitted as encoded speech. On the decoder side, by looking up the same codebooks, pitch, intensity and the timbre vector are recovered. Using Laguerre functions, the amplitude spectrum is recovered. Using Kramers-Kronig relations, the phase spectrum is recovered. Using FFT, the elementary waves are regenerated, and superposed to become the speech signal.
    Type: Application
    Filed: January 26, 2015
    Publication date: September 17, 2015
    Inventor: Chengjun Julian Chen
  • Patent number: 9135923
    Abstract: A pitch-synchronous method and system for speech coding using timbre vectors is disclosed. On the encoder side, speech signal is segmented into pitch-synchronous frames without overlap, then converted into a pitch-synchronous amplitude spectrum using FFT. Using Laguerre functions, the amplitude spectrum is transformed into a timbre vector. Using vector quantization, each timbre vector is converted to a timbre index based on a timbre codebook. The intensity and pitch are also converted into indices respectively using scalar quantization. Those indices are transmitted as encoded speech. On the decoder side, by looking up the same codebooks, pitch, intensity and the timbre vector are recovered. Using Laguerre functions, the amplitude spectrum is recovered. Using Kramers-Kronig relations, the phase spectrum is recovered. Using FFT, the elementary waves are regenerated, and superposed to become the speech signal.
    Type: Grant
    Filed: January 26, 2015
    Date of Patent: September 15, 2015
    Inventor: Chengjun Julian Chen
  • Patent number: 8942977
    Abstract: The present invention defines a pitch-synchronous parametrical representation of speech signals as the basis of speech recognition, and discloses methods of generating the said pitch-synchronous parametrical representation from speech signals. The speech signal is first going through a pitch-marks picking program to identify the pitch periods. The speech signal is then segmented into pitch-synchronous frames. An ends-matching program equalizes the values at the two ends of the waveform in each frame. Using Fourier analysis, the speech signal in each frame is converted into a pitch-synchronous amplitude spectrum. Using Laguerre functions, the said amplitude spectrum is converted into a unit vector, referred to as the timbre vector. By using a database of correlated phonemes and timbre vectors, the most likely phoneme sequence of an input speech signal can be decoded in the acoustic stage of a speech recognition system.
    Type: Grant
    Filed: March 17, 2014
    Date of Patent: January 27, 2015
    Inventor: Chengjun Julian Chen
  • Patent number: 8886539
    Abstract: The present invention discloses a parametrical representation of prosody based on polynomial expansion coefficients of the pitch contour near the center of each syllable. The said syllable pitch expansion coefficients are generated from a recorded speech database, read from a number of sentences by a reference speaker. By correlating the stress level and context information of each syllable in the text with the polynomial expansion coefficients of the corresponding spoken syllable, a correlation database is formed. To generate prosody for an input text, stress level and context information of each syllable in the text is identified. The prosody is generated by using the said correlation database to find the best set of pitch parameters for each syllable. By adding to global pitch contours and using interpolation formulas, complete pitch contour for the input text is generated. Duration and intensity profile are generated using a similar procedure.
    Type: Grant
    Filed: March 17, 2014
    Date of Patent: November 11, 2014
    Inventor: Chengjun Julian Chen
  • Publication number: 20140200889
    Abstract: The present invention defines a pitch-synchronous parametrical representation of speech signals as the basis of speech recognition, and discloses methods of generating the said pitch-synchronous parametrical representation from speech signals. The speech signal is first going through a pitch-marks picking program to identify the pitch periods. The speech signal is then segmented into pitch-synchronous frames. An ends-matching program equalizes the values at the two ends of the waveform in each frame. Using Fourier analysis, the speech signal in each frame is converted into a pitch-synchronous amplitude spectrum. Using Laguerre functions, the said amplitude spectrum is converted into a unit vector, referred to as the timbre vector. By using a database of correlated phonemes and timbre vectors, the most likely phoneme sequence of an input speech signal can be decoded in the acoustic stage of a speech recognition system.
    Type: Application
    Filed: March 17, 2014
    Publication date: July 17, 2014
    Inventor: Chengjun Julian Chen
  • Publication number: 20140195242
    Abstract: The present invention discloses a parametrical representation of prosody based on polynomial expansion coefficients of the pitch contour near the center of each syllable. The said syllable pitch expansion coefficients are generated from a recorded speech database, read from a number of sentences by a reference speaker. By correlating the stress level and context information of each syllable in the text with the polynomial expansion coefficients of the corresponding spoken syllable, a correlation database is formed. To generate prosody for an input text, stress level and context information of each syllable in the text is identified. The prosody is generated by using the said correlation database to find the best set of pitch parameters for each syllable. By adding to global pitch contours and using interpolation formulas, complete pitch contour for the input text is generated. Duration and intensity profile are generated using a similar procedure.
    Type: Application
    Filed: March 17, 2014
    Publication date: July 10, 2014
    Inventor: Chengjun Julian Chen
  • Patent number: 8744854
    Abstract: The present invention is a method and system to convert speech signal into a parametric representation in terms of timbre vectors, and to recover the speech signal thereof. The speech signal is first segmented into non-overlapping frames using the glottal closure instant information, each frame is converted into an amplitude spectrum using a Fourier analyzer, and then using Laguerre functions to generate a set of coefficients which constitute a timbre vector. A sequence of timbre vectors can be subject to a variety of manipulations. The new timbre vectors are converted back into voice signals by first transforming into amplitude spectra using Laguerre functions, then generating phase spectra from the amplitude spectra using Kramers-Knonig relations. A Fourier transformer converts the amplitude spectra and phase spectra into elementary waveforms, then superposed to become the output voice. The method and system can be used for voice transformation, speech synthesis, and automatic speech recognition.
    Type: Grant
    Filed: September 24, 2012
    Date of Patent: June 3, 2014
    Inventor: Chengjun Julian Chen
  • Publication number: 20140142946
    Abstract: The present invention is a method and system to convert speech signal into a parametric representation in terms of timbre vectors, and to recover the speech signal thereof. The speech signal is first segmented into non-overlapping frames using the glottal closure instant information, each frame is converted into an amplitude spectrum using a Fourier analyzer, and then using Laguerre functions to generate a set of coefficients which constitute a timbre vector. A sequence of timbre vectors can be subject to a variety of manipulations. The new timbre vectors are converted back into voice signals by first transforming into amplitude spectra using Laguerre functions, then generating phase spectra from the amplitude spectra using Kramers-Knonig relations. A Fourier transformer converts the amplitude spectra and phase spectra into elementary waveforms, then superposed to become the output voice. The method and system can be used for voice transformation, speech synthesis, and automatic speech recognition.
    Type: Application
    Filed: September 24, 2012
    Publication date: May 22, 2014
    Inventor: Chengjun Julian Chen
  • Patent number: 8719030
    Abstract: The present invention is a method and system to convert speech signal into a parametric representation in terms of timbre vectors, and to recover the speech signal thereof. The speech signal is first segmented into non-overlapping frames using the glottal closure instant information, each frame is converted into an amplitude spectrum using a Fourier analyzer, and then using Laguerre functions to generate a set of coefficients which constitute a timbre vector. A sequence of timbre vectors can be subject to a variety of manipulations. The new timbre vectors are converted back into voice signals by first transforming into amplitude spectra using Laguerre functions, then generating phase spectra from the amplitude spectra using Kramers-Knonig relations. A Fourier transformer converts the amplitude spectra and phase spectra into elementary acoustic waves, then superposed to become the output voice. The method and system can be used for voice transformation, speech synthesis, and automatic speech recognition.
    Type: Grant
    Filed: December 3, 2012
    Date of Patent: May 6, 2014
    Inventor: Chengjun Julian Chen
  • Publication number: 20140088968
    Abstract: The present invention is a method and system to convert speech signal into a parametric representation in terms of timbre vectors, and to recover the speech signal thereof. The speech signal is first segmented into non-overlapping frames using the glottal closure instant information, each frame is converted into an amplitude spectrum using a Fourier analyzer, and then using Laguerre functions to generate a set of coefficients which constitute a timbre vector. A sequence of timbre vectors can be subject to a variety of manipulations. The new timbre vectors are converted back into voice signals by first transforming into amplitude spectra using Laguerre functions, then generating phase spectra from the amplitude spectra using Kramers-Knonig relations. A Fourier transformer converts the amplitude spectra and phase spectra into elementary waveforms, then superposed to become the output voice. The method and system can be used for voice transformation, speech synthesis, and automatic speech recognition.
    Type: Application
    Filed: December 3, 2012
    Publication date: March 27, 2014
    Inventor: Chengjun Julian Chen
  • Publication number: 20140088958
    Abstract: The present invention is a method and system to convert speech signal into a parametric representation in terms of timbre vectors, and to recover the speech signal thereof. The speech signal is first segmented into non-overlapping frames using the glottal closure instant information, each frame is converted into an amplitude spectrum using a Fourier analyzer, and then using Laguerre functions to generate a set of coefficients which constitute a timbre vector. A sequence of timbre vectors can be subject to a variety of manipulations. The new timbre vectors are converted back into voice signals by first transforming into amplitude spectra using Laguerre functions, then generating phase spectra from the amplitude spectra using Kramers-Knonig relations. A Fourier transformer converts the amplitude spectra and phase spectra into elementary acoustic waves, then superposed to become the output voice. The method and system can be used for voice transformation, speech synthesis, and automatic speech recognition.
    Type: Application
    Filed: December 3, 2012
    Publication date: March 27, 2014
    Inventor: Chengjun Julian Chen
  • Publication number: 20120132195
    Abstract: A solar water heater including a heat separator containing either a single partition wall that connects in parallel colder water entering all-glass evacuated tubes with hotter water exiting the same all-glass evacuated tubes, or a number of partition walls that connect in series colder water entering each all-glass evacuated tube with hotter water exiting each all-glass evacuated tube. As water in the evacuated tubes is heated by solar radiation, a hydrodynamic head is created which forces the hot water in the evacuated tubes to flow automatically into the hot water compartment(s) of the heat separator(s) and subsequently through an insulated pipe to a water tank without requiring a pump. The cool water in the water tank flows automatically through an insulated pipe back into the cool water compartment(s) of the heat separator(s) in order to preserve flow continuity.
    Type: Application
    Filed: December 22, 2011
    Publication date: May 31, 2012
    Inventors: Chengjun Julian Chen, Clark Theodore Gordon
  • Patent number: 8181474
    Abstract: A solar-powered air conditioning system including an energy-storage medium made of a mixture of 5%-20% glycerin, 2.5%-10% alcohol and water in a thermally insulated container is disclosed. While frozen, the said energy storage medium becomes slurry of thin sheets of ice dispersed in liquid, which will not damage the container and the heat-exchange pipes. The system uses a solar photovoltaic panel to directly drive a vapor-compression refrigeration unit to freeze the said energy storage medium. A ventilation system forces air through a heat-exchange coil in the said energy-storage medium, to generate chilled air to cool the space. In the absence of sunlight, the energy-storage medium can keep frozen for days. With or without sunlight, the flowing air chilled by the frozen energy-storage medium continues to cool the room or the entire building.
    Type: Grant
    Filed: June 8, 2009
    Date of Patent: May 22, 2012
    Inventor: Chengjun Julian Chen
  • Patent number: 7698825
    Abstract: The most accurate method of finding the true north is through astronomical observations, for example, by observing the position of the sun. However, the procedure is complicated. The instantaneous position of the sun must be calculated from astronomical data for each instance of observation, and the operator must wait for the predetermined time to come. Elaborate manual adjustments are required. The present invention discloses an automatic solar compass comprising a cylindrical omni-directional lens, a detection means, and a servomechanism. It is as easy to use as the magnetic compass, but much more accurate and reliable than the magnetic compass.
    Type: Grant
    Filed: August 17, 2007
    Date of Patent: April 20, 2010
    Assignee: The Trustees of Columbia University in the City of New York
    Inventor: Chengjun Julian Chen
  • Publication number: 20090301119
    Abstract: A solar-powered air conditioning system comprising an energy-storage medium made of a mixture of 5%-20% glycerin, 2.5%-10% alcohol and water in a thermally insulated container is disclosed. While frozen, the said energy storage medium becomes slurry of thin sheets of ice dispersed in liquid, which will not damage the container and the heat-exchange pipes. The system uses a solar photovoltaic panel to directly drive a vapor-compression refrigeration unit to freeze the said energy storage medium. A ventilation system forces air through a heat-exchange coil in the said energy-storage medium, to generate chilled air to cool the space. In the absence of sunlight, the energy-storage medium can keep frozen for days. With or without sunlight, the flowing air chilled by the frozen energy-storage medium continues to cool the room or the entire building.
    Type: Application
    Filed: June 8, 2009
    Publication date: December 10, 2009
    Inventor: Chengjun Julian Chen
  • Publication number: 20090301118
    Abstract: A solar-powered air conditioning system comprising an energy-storage medium of 5%-10% glycerin and 90%-95% water in a thermally insulated container, a solar photovoltaic panel, a vapor-compression refrigeration unit driven by a DC motor powered directly by the solar photovoltaic panel, a heat-exchange coil to cool a stream of air by the energy-storage medium, and a ventilation apparatus to circulate the cooled air. In the presence of sunlight, the electrical current generated by the solar panels drives the vapor-compression refrigeration unit to freeze the mixture of glycerin and water. In the absence of sunlight, the frozen mixture of glycerin and water keeps temperature low. The flowing air cooled by heat-exchange coils through the energy-storage medium circulates in the room or the entire building to keep the space cool.
    Type: Application
    Filed: June 6, 2008
    Publication date: December 10, 2009
    Inventor: Chengjun Julian Chen
  • Publication number: 20090183853
    Abstract: A solar-powered cooling and heating system comprising one or more vertical water containers of special design as the thermal storage device (the structured water wall), a compressor driven by a DC motor powered directly by solar photovoltaic panel(s) for cooling, and a south-faced window for direct solar heating. The solar photovoltaic panel(s) is placed on an awning above the south-facing window; the said awning is designed to allow full sunlight in the winter but no direct sunlight in the summer through the window. The thermal inertia of the structured water wall allows optimum heating and cooling day and night for all seasons of a year. It allows an automatic self-adjustment utilizing the natural annual and diurnal cycles to achieve maximum comfort and efficiency.
    Type: Application
    Filed: January 22, 2008
    Publication date: July 23, 2009
    Inventor: Chengjun Julian Chen
  • Patent number: 7555840
    Abstract: Sundials and solar compasses including are disclosed. Some embodiments include an omni-directional lens, which can focus a sun beam into a sharp spot with a long depth of field. By projecting the spot onto a cylindrical panel, both the day of the year and the time of the day can be read off simultaneously with very high accuracy. Because of the simultaneous displaying of time and date, no equation-of-time correction is required. If the time is known, the true north can be determined with high accuracy, and the device becomes a reliable and easy-to-use solar compass.
    Type: Grant
    Filed: August 17, 2007
    Date of Patent: July 7, 2009
    Assignee: The Trustees of Columbia University in the City of New York
    Inventor: Chengjun Julian Chen