Patents by Inventor Dong Kyu Choi

Dong Kyu Choi 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: 20160215929
    Abstract: A liquefied gas treatment method for a vessel is performed by a liquefied gas treatment system for the vessel including a cargo tank storing LNG, and a main engine and a sub engine using the LNG stored in the cargo tank as fuel. The liquefied gas treatment system includes a compressor line configured to compress BOG generated in the cargo tank by a compressor and supply the compressed BOG to the engines as fuel, and a pump line configured to compress the LNG stored in the cargo tank by a pump and supply the compressed LNG to the engines as fuel. In a laden condition in which an amount of the LNG stored in the cargo tank is larger than in a ballast condition, the BOG generated in the cargo tank is supplied as fuel to at least one of the engines through the compressor line.
    Type: Application
    Filed: April 5, 2016
    Publication date: July 28, 2016
    Inventors: Joon Chae LEE, Soon Been KWON, Dong Kyu CHOI, Young Sik MOON, Dong Chan KIM, Jeheon JUNG, Nam Soo KIM
  • Publication number: 20160114876
    Abstract: In a BOG treatment system, boil-off gas (BOG) discharged from a storage tank is compressed, most of the BOG is used as the fuel of vessel engines, and a remaining part of the BOG is liquefied by cold energy of BOG newly discharged from the storage tank and is returned to the storage tank, thereby efficiently utilizing the BOG. The BOG treatment system for a vessel includes a compressor compressing the BOG discharged from the storage tank; a medium pressure gas engine receiving at least a part of the BOG compressed by the compressor, as fuel; a heat exchanger exchanging heat between the remaining part of the BOG, which is not supplied to the medium pressure gas engine as fuel, and the BOG, which is discharged from the storage tank and is not compressed; and an expander decompressing the remaining part of the BOG cooled by the heat exchanger.
    Type: Application
    Filed: June 26, 2014
    Publication date: April 28, 2016
    Inventors: Joon Chae LEE, Dong Kyu CHOI, Young Sik MOON, Seung Kyo JUNG, Je Heon JUNG
  • Publication number: 20160079679
    Abstract: Disclosed are a non-feeding re-radiating repeater and a method for manufacturing the same. The repeater includes: a dielectric substrate having a flat plate shape or a curved shape; and one or more unit cells formed on the dielectric substrate, in which each of the unit cells includes an arrangement of a plurality of conductor patterns. When electromagnetic waves incident from a first direction, the unit cells may re-radiate the electromagnetic waves in a second direction which is different from the first direction.
    Type: Application
    Filed: September 15, 2015
    Publication date: March 17, 2016
    Inventors: Hyun-Jin KIM, Byung-Chul KIM, Young-Ju LEE, Jung-Yub LEE, Dong-Kyu CHOI
  • Patent number: 9239186
    Abstract: Provided is a method for operating a fuel supply system for a marine structure. The fuel supply system includes a BOG compression unit configured to receive and compress BOG generated in a storage tank, a reliquefaction apparatus configured to receive and liquefy the BOG compressed by the BOG compression unit, a high-pressure pump configured to compress the liquefied BOG generated by the reliquefaction apparatus, and a high-pressure gasifier configured to gasify the liquefied BOG compressed by the high-pressure pump. The fuel supply system includes a recondenser installed at an upstream side of the high-pressure pump, and the recondenser recondenses a portion or all of the generated BOG by using liquefied gas supplied from the storage tank. During a ballast voyage process, all of the BOG is supplied to and recondensed by the recondenser, and an operation of the reliquefaction apparatus is interrupted.
    Type: Grant
    Filed: December 20, 2011
    Date of Patent: January 19, 2016
    Assignee: DAEWOO SHIPBUILDING & MARINE ENGINEERING CO., LTD.
    Inventors: Seung Kyo Jung, Je Heon Jung, Jung Han Lee, Hyun Jun Shin, Sung Jun Lee, Dong Kyu Choi
  • Publication number: 20150368617
    Abstract: The present application discloses a method of promoting differentiation and expansion of endothelial cells (EC) and cardiomyocytes from a pluripotent cell, which includes contacting the pluripotent cell with a Rho-associated protein kinase (ROCK) suppressor.
    Type: Application
    Filed: May 7, 2014
    Publication date: December 24, 2015
    Applicant: Korea Advanced Institute of Science and Technology (KAIST)
    Inventors: Gou Young KOH, Hyung Joon Joo, Dong Kyu Choi, Jin-Sung Park, Sung Woo Cho
  • Patent number: 9168993
    Abstract: A vessel includes a cargo tank storing LNG, a main engine and a sub engine using the LNG stored in the cargo tank as fuel, and a liquefied gas treatment system which includes: a main BOG supply line configured to compress the BOG generated in the cargo tank by a compressor and supply the compressed BOG to the main engine as fuel; a sub BOG supply line configured to compress BOG generated in the cargo tank by a compressor and supply the compressed BOG to the sub engine as fuel; a main LNG supply line configured to compress the LNG stored in the cargo tank by a pump and supply the compressed LNG to the main engine as fuel; and a sub LNG supply line configured to compress the LNG stored in the cargo tank by a pump and supply the compressed LNG to the sub engine as fuel.
    Type: Grant
    Filed: April 21, 2015
    Date of Patent: October 27, 2015
    Assignee: DAEWOO SHIPBUILDING & MARINE ENGINEERING CO., LTD.
    Inventors: Joon Chae Lee, Dong Kyu Choi, Young Sik Moon, Jeheon Jung
  • Publication number: 20150300301
    Abstract: Provided is a liquefied gas treatment system for a vessel, which includes a cargo tank storing liquefied natural gas (LNG), and an engine using the LNG as fuel. The liquefied gas treatment system includes: a compressor line configured to compress boil-off gas (BOG) generated in the cargo tank by a compressor and supply the compressed BOG to the engine as fuel; a high pressure pump line configured to compress the LNG stored in the cargo tank by a pump and supply the compressed LNG to the engine as fuel; and a heat exchanger configured to liquefy a part of BOG, which is compressed by the compressor, by exchanging heat with BOG that is discharged from the cargo tank and transferred to the compressor.
    Type: Application
    Filed: October 24, 2013
    Publication date: October 22, 2015
    Inventors: Joon Chae LEE, Soon Been KWON, Nam Soo KIM, Dong Kyu CHOI, Jeheon JUNG, Young Sik MOON, Dong Chan KIM
  • Publication number: 20150285189
    Abstract: A hybrid fuel supply system for an engine of a vessel is provided. The hybrid fuel supply system for the engine of the vessel includes: a compression device configured to compress boil-off gas (BOG) generated from liquefied natural gas (LNG) stored in an LNG cargo tank; a high pressure pump configured to compress LNG supplied from the LNG cargo tank; a vaporizer configured to vaporize the LNG compressed by the high pressure pump; and a dual fuel (DF) engine to which the BOG compressed through the compression device is supplied as fuel. The engine of the vessel uses high pressure gas compressed at 150 to 400 bar as fuel and is driven by at least one of the BOG compressed in the compression device and the LNG compressed in the high pressure pump.
    Type: Application
    Filed: October 24, 2013
    Publication date: October 8, 2015
    Inventors: Joon Chae Lee, Dong Kyu Choi, Young Sik Moon, Seung Kyo Jung, Jeheon Jung, Nam Soo Kim
  • Publication number: 20150226379
    Abstract: A liquefied gas treatment method for a vessel is performed by a liquefied gas treatment system for the vessel including a cargo tank storing LNG, and a main engine and a sub engine using the LNG stored in the cargo tank as fuel. The liquefied gas treatment system includes a compressor line configured to compress BOG generated in the cargo tank by a compressor and supply the compressed BOG to the engines as fuel, and a pump line configured to compress the LNG stored in the cargo tank by a pump and supply the compressed LNG to the engines as fuel. In a laden condition in which an amount of the LNG stored in the cargo tank is larger than in a ballast condition, the BOG generated in the cargo tank is supplied as fuel to at least one of the engines through the compressor line.
    Type: Application
    Filed: April 21, 2015
    Publication date: August 13, 2015
    Inventors: Joon Chae LEE, Soon Been KWON, Dong Kyu CHOI, Young Sik MOON, Dong Chan KIM, Jeheon JUNG, Nam Soo KIM
  • Patent number: 9086188
    Abstract: Disclosed is a system for reducing a heating value of natural gas. The system includes a heat exchanger to liquefy a portion of components having high heating values, a gas-liquid separator to separate the liquefied component, and a nitrogen adding mechanism to add nitrogen to remaining non-liquefied components. The system includes an additional heat exchanger to cool and liquefy the remaining non-liquefied components after the gas-liquid separator separates the liquefied component from the natural gas. The heat exchangers employ cold heat generated upon regasification of LNG. The system can reduce the heating value of natural gas composed of a variety of hydrocarbon components according to requirements of a place of demand by separating the component with the higher heating value from the natural gas to allow the separated component to be used as fuel, thereby reducing an overall size and operating costs of the system.
    Type: Grant
    Filed: July 21, 2008
    Date of Patent: July 21, 2015
    Assignee: DAEWOO SHIPBUILDING & MARINE ENGINEERING CO., LTD.
    Inventors: Jung Han Lee, Young Sik Moon, Dong Kyu Choi, Young Soo Kim, Jong Hyun Park
  • Patent number: 9067661
    Abstract: A ship includes: a high-pressure injection engine using fuel gas as fuel to obtain a propulsion power of the ship; a generator engine using fuel gas as fuel to generate electricity; a motor generating a power by using the electricity generated from the generator engine; a propulsion propelling the ship; a main clutch connecting the high-pressure injection engine to the propulsion; an auxiliary clutch connecting the gear box to the propulsion; and a gear box disposed in a front side of the propulsion and power-connected to the main clutch and the auxiliary clutch. The high-pressure injection engine and the motor are selectively power-connected to the propulsion to obtain the propulsion power of the ship.
    Type: Grant
    Filed: May 30, 2014
    Date of Patent: June 30, 2015
    Assignee: DAEWOO SHIPBUILDING & MARINE ENGINEERING CO., LTD.
    Inventors: Jin Kwang Lee, Dong Kyu Choi, Jung Han Lee
  • Patent number: 8959930
    Abstract: Disclosed are a method and an apparatus for treating boil-off gas generated in an LNG storage tank of an LNG carrier for transporting LNG in a cryogenic liquid state, the LNG carrier having a boil-off gas reliquefaction plant, wherein an amount of boil-off gas corresponding to a treatment capacity of the reliquefaction plant among the total amount of boil-off gas generated during the voyage of the LNG carrier is discharged from the LNG storage tank and reliquefied by the reliquefaction plant. The boil-off gas treating method and apparatus can maintain an amount of boil-off gas discharged from an LNG storage tank at a constant level by storing in the LNG storage tank, instead of discharging and burning, surplus boil-off gas which has not been returned to the LNG storage tank through the reliquefaction plant among the total amount of boil-off gas generated in the LNG storage tank, and can prevent waste of boil-off gas and save energy by allowing an internal pressure of the LNG storage tank to be increased.
    Type: Grant
    Filed: September 20, 2007
    Date of Patent: February 24, 2015
    Assignee: Daewoo Shipbuilding & Marine Engineering Co., Ltd.
    Inventors: Jung Han Lee, Jin Yul Yu, Dong Kyu Choi, Hyun Ki Park, Hyun Jin Kim
  • Patent number: 8943841
    Abstract: Disclosed is a liquefied natural gas storage apparatus. The apparatus includes a heat insulated tank and liquefied natural gas contained in the tank. The tank has heat insulation sufficient to maintain liquefied natural gas therein such that most of the liquefied natural gas stays in liquid. The contained liquefied natural gas has a vapor pressure from about 0.3 bar to about 2 bar. The apparatus further includes a safety valve configured to release a part of liquefied natural gas contained in the tank when a vapor pressure of liquefied natural gas within the tank becomes higher than a cut off pressure. The cut off pressure is from about 0.3 bar to about 2 bar.
    Type: Grant
    Filed: April 23, 2009
    Date of Patent: February 3, 2015
    Assignee: Daewoo Shipbuilding & Marine Engineering Co., Ltd.
    Inventors: Jung Han Lee, Jung Ho Choi, Sung Kon Han, Dong Kyu Choi, Young Sik Moon
  • Publication number: 20140290279
    Abstract: A liquefied gas treatment system includes: a first stream of boil-off gas, which is generated from the liquefied natural gas in the cargo tank and is discharged from the cargo tank; a second stream of the boil-off gas, which is supplied as fuel to the engine in the first stream; and a third stream of the boil-off gas, which is not supplied to the engine in the first stream. The first stream is compressed in a compressor and is then branched into the second stream and the third stream. The third stream is liquefied by exchanging heat with the first stream in a heat exchanger, so that the boil-off gas is treated without employing a reliquefaction apparatus using a separate refrigerant.
    Type: Application
    Filed: October 24, 2013
    Publication date: October 2, 2014
    Applicant: DAEWOO SHIPBUILDING & MARINE ENGINEERING CO., LTD
    Inventors: Joon Chae Lee, Dong Kyu Choi, Young Sik Moon, Seung Kyo Jung, Jeheon Jung, Nam Soo Kim
  • Publication number: 20140260255
    Abstract: A ship includes: a high-pressure injection engine using fuel gas as fuel to obtain a propulsion power of the ship; a generator engine using fuel gas as fuel to generate electricity; a motor generating a power by using the electricity generated from the generator engine; a propulsion propelling the ship; a main clutch connecting the high-pressure injection engine to the propulsion; an auxiliary clutch connecting the gear box to the propulsion; and a gear box disposed in a front side of the propulsion and power-connected to the main clutch and the auxiliary clutch. The high-pressure injection engine and the motor are selectively power-connected to the propulsion to obtain the propulsion power of the ship.
    Type: Application
    Filed: May 30, 2014
    Publication date: September 18, 2014
    Applicant: DAEWOO SHIPBUILDING & MARINE ENGINEERING CO., LTD.
    Inventors: Jin Kwang Lee, Dong Kyu Choi, Jung Han Lee
  • Patent number: 8834218
    Abstract: Disclosed herein is a floating structure with a fuel gas tank storing a gaseous fuel used as fuel in a dual fuel propulsion system disposed under a cargo space. According to the present invention, there is provided a floating structure with a fuel gas tank storing a gaseous fuel used as fuel and used while floating at sea, including: a fuel gas tank disposed in the hull of the floating structure; and a cargo space disposed on the top of the fuel gas tank on the upper deck of the floating structure.
    Type: Grant
    Filed: October 5, 2010
    Date of Patent: September 16, 2014
    Assignee: Daewoo Shipbuilding & Marine Engineering Co., Ltd.
    Inventors: Sung Jun Lee, Yoon Chul Byun, Dong Kyu Choi
  • Patent number: 8820096
    Abstract: Disclosed is a liquefied natural gas storage apparatus. The apparatus includes a heat insulated tank and liquefied natural gas contained in the tank. The tank has heat insulation sufficient to maintain liquefied natural gas therein such that most of the liquefied natural gas stays in liquid. The contained liquefied natural gas has a vapor pressure from about 0.3 bar to about 2 bar. The apparatus further includes a safety valve configured to release a part of liquefied natural gas contained in the tank when a vapor pressure of liquefied natural gas within the tank becomes higher than a cut-off pressure. The cut-off pressure is from about 0.3 bar to about 2 bar.
    Type: Grant
    Filed: July 26, 2007
    Date of Patent: September 2, 2014
    Assignee: Daewoo Shipbuilding & Marine Engineering Co., Ltd.
    Inventors: Jung Han Lee, Jung Ho Choi, Sung Kon Han, Dong Kyu Choi, Young Sik Moon
  • Publication number: 20140075943
    Abstract: Provided is a method for operating a fuel supply system for a marine structure. The fuel supply system includes a BOG compression unit configured to receive and compress BOG generated in a storage tank, a reliquefaction apparatus configured to receive and liquefy the BOG compressed by the BOG compression unit, a high-pressure pump configured to compress the liquefied BOG generated by the reliquefaction apparatus, and a high-pressure gasifier configured to gasify the liquefied BOG compressed by the high-pressure pump. The fuel supply system includes a recondenser installed at an upstream side of the high-pressure pump, and the recondenser recondenses a portion or all of the generated BOG by using liquefied gas supplied from the storage tank. During a ballast voyage process, all of the BOG is supplied to and recondensed by the recondenser, and an operation of the reliquefaction apparatus is interrupted.
    Type: Application
    Filed: December 20, 2011
    Publication date: March 20, 2014
    Applicant: DAEWOO SHIPBUILDING & MARINE ENGINEERING CO., LTD.
    Inventors: Seung Kyo Jung, Je Heon Jung, Jung Han Lee, Sung Jun Lee, Hyun Jun Shin, Dong Kyu Choi
  • Publication number: 20140069118
    Abstract: Provided is a fuel supply system for a marine structure using a high-pressure natural gas injection engine. The fuel supply system includes: a boil-off gas (BOG) compression unit configured to receive and compress BOG generated in a storage tank storing a liquefied gas; a reliquefaction apparatus configured to receive and liquefy the BOG compressed by the BOG compression unit; a buffer tank configured to receive the liquefied BOG from the reliquefaction apparatus and separate the reliquefied BOG into a gaseous component and a liquid component; a high-pressure pump configured to receive the liquid component from the buffer tank and compress the liquid component; and a high-pressure gasifier configured to gasify the liquid component compressed by the high-pressure pump and supply the gasified liquid component to the high-pressure natural gas injection engine.
    Type: Application
    Filed: December 20, 2011
    Publication date: March 13, 2014
    Applicant: DAEWOO SHIPBUILDING & MARINE ENGINEERING CO., LTD.
    Inventors: Seung Kyo Jung, Jung Han Lee, Je Heon Jung, Sung Jun Lee, Hyun Jun Shin, Dong Kyu Choi
  • Publication number: 20140069117
    Abstract: Provided is a nonflammable mixed refrigerant for use in a reliquefaction apparatus of a fuel supply system that compresses BOG generated in an LNG storage tank to a medium pressure, reliquefies the compressed BOG, compresses the reliquefied BOG to a high pressure, gasifies the compressed requefied BOG, and supplies the gasified BOG to a high-pressure natural gas injection engine. A nonflammable mixed refrigerant for use in a fuel supply system for a high-pressure natural gas injection engine is provided. The nonflammable mixed refrigerant cools the BOG by heat exchange with the BOG in the reliquefaction apparatus. The nonflammable mixed refrigerant comprises a mixture of nonflammable refrigerants with different boiling points, and the boiling point of each of the nonflammable refrigerant ranges between a room temperature and a liquefaction temperature of natural gas.
    Type: Application
    Filed: December 20, 2011
    Publication date: March 13, 2014
    Applicant: DAEWOO SHIPBUILDING & MARINE ENGINEERING CO., LTD.
    Inventors: Seung Kyo Jung, Je Heon Jung, Dong Kyu Choi, Jung Han Lee, Young Sik Moon, Jin Yeol Yu