Patents by Inventor Keun Chang

Keun Chang 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: 20050271526
    Abstract: A driving unit and control method for a reciprocating compressor for controlling a frequency of input power so that an operational frequency of the compressor follows a resonant frequency, which varies depending on a variation of the load applied to the compressor. The reciprocating compressor includes an inverter to adjust the frequency of the input power, so that the frequency of the input power is set at a value corresponding to the resonant frequency by the inverter. The resonant frequency is set in a range of 60% to 90% of the normal power frequency. The compressor further includes a controller to control the frequency of the input power so that the operational frequency of the compressor follows the resonant frequency, which varies depending on the operation of the compressor.
    Type: Application
    Filed: April 20, 2005
    Publication date: December 8, 2005
    Applicant: Samsung Electronics Co., Ltd.
    Inventors: Keun Chang, Phil Chang
  • Patent number: 6596521
    Abstract: The present invention provides a method for manufacturing organic acid by high-efficiency fermentation, which comprises the steps of continuous culture of organic acid bacteria and collection of organic acid produced from the culture employing a cell-recycle multiple-stage continuous fermentor with serially connected fermentors, each of which comprises a fermentor containing a ferment container, temperature controller, stirrer, and pH controller; pumps for efflux-circulation of media from the fermentor; and, cell separator for separation and circulation of media from the pumps. According to the present method, the high-concentration lactic acid of 90 g/L can be produced with the high productivity of 50 g/L/h, which can reduce the facility cost and production cost in the bulk manufacturing process.
    Type: Grant
    Filed: April 13, 2000
    Date of Patent: July 22, 2003
    Assignee: Korea Advanced Institute of Science and Technology
    Inventors: Ho Nam Chang, Yong Keun Chang, Sun Hoon Kwon, Woo Gi Lee, Pyung Cheon Lee, Ik Keun Yoo, Seong Jin Lim
  • Patent number: 6480307
    Abstract: A plane light source unit for backlighting and a method for manufacturing holographic light-guides used for the same is disclosed. The holographic light-guide has a first holographic layer on the bottom surface. The first holographic layer has patterns formed with a plurality of holograms, the area density of the pattern being low toward the tubular light source and increasing with an increase in distance from the tubular light source, thereby uniformly illuminating the LCD panel. The holographic light-guide also has a second holographic layer on the top surface, the second holographic layer adjusting scattering pattern of the beam emerged from the light-guide plate.
    Type: Grant
    Filed: June 30, 2000
    Date of Patent: November 12, 2002
    Inventor: Keun-Chang Yang
  • Patent number: 6348414
    Abstract: There is provided a method for forming fine metal patterns of semiconductor devices using damascene technique. In the method, a glue layer and a diffusion barrier film are formed on a lower layer, in turn. An insulating film is then deposited on the barrier film and etched to form contact holes or via holes. A metal film is then deposited within the hole to form a fine metal pattern. Therefore, the method can increase the width of the metal film of the fine pattern, thereby enhancing the operation speed of the device. The method can also easily control the processes by separating the etching process of the metal film from those of the glue layer and the barrier film.
    Type: Grant
    Filed: December 21, 1999
    Date of Patent: February 19, 2002
    Assignee: Hyundai Electronics Industries Co., Ltd.
    Inventors: Hee-Yong Yun, Sung-Keun Chang
  • Publication number: 20010046716
    Abstract: A method for manufacturing a semiconductor device includes the steps of: a) preparing an active matrix provided with at least one transistor, a plurality of conductive plugs electrically connected to the transistors and an insulating layer formed around the conductive plugs; b) forming a conductive layer on top of the active matrix; c) patterning the conductive layer a predetermined configuration, thereby obtaining a number of bottom electrodes; d) forming a first BST layer; and e) forming a second BST layer.
    Type: Application
    Filed: December 20, 2000
    Publication date: November 29, 2001
    Inventors: You-Sung Kim, Min Huh, Sung-Keun Chang
  • Patent number: 6238625
    Abstract: The present invention relates to a sealed high-density on-line measuring device for spectrophotometer whose cuvette holder is linked to a reactor, which comprises a base; a fixed plate for light passage, which is vertically placed on the base; a moving plate for light radiation, which is vertically placed on the base at an opposite side to the fixed plate so that it can slide on the base horizontally; inlet and outlet for sample passage, each of which is positioned at outer side of the moving plate; a metal ring linking the fixed plate and the moving plate; and, upper and lower shielders each of whose ends is in contact with the fixed plate and moving plate, respectively, to give a sealed space. In accordance with the scaled on-line measuring device of the invention, high concentrations of samples in solutions can be measured without dilution, by way of employing a newly designed cuvette holder in a spectrophotometer fitted to a reactor.
    Type: Grant
    Filed: December 18, 1998
    Date of Patent: May 29, 2001
    Assignee: Korea Advanced Institute of Science and Technology
    Inventors: Yong Keun Chang, Jong Dae Lee, Yong Ho Jung
  • Patent number: 6204046
    Abstract: The present invention relates to Gordona sp. CYKS1 (KCTC 0431BP) capable of selective removal of organically bound sulfurs from carbonaceous fossil fuel such as petroleum and coal by cleaving bonds between carbon and sulfur atoms in the said sulfur-containing organic compounds, and a method for biological desulfurization using this strain at the room temperature and atmospheric pressure. Since Gordona sp. CYKS1 (KCTC 0431BP) utilizes various organic sulfur compounds in fossil fuel besides dibenzothiophene as a sole sulfur source, the method for biological desulfurization employing the Gordona strain has advantages over the conventional chemical methods as followings: The desulfurization can be carried out at a mild condition; the cost for installation and operation of equipments can be reduced; and, the desulfurization of highly complex organic sulfur compounds can be realized.
    Type: Grant
    Filed: March 3, 1999
    Date of Patent: March 20, 2001
    Assignee: Korea Advanced Institute of Science and Technology
    Inventors: Yong Keun Chang, Ho Nam Chang, Sung-Keun Rhee, Je Hwan Chang, Jung Hyun Sung
  • Patent number: 6197570
    Abstract: The present invention relates to Nocardia sp. CYKS2 (KCTC 0432 Br) capable of selective removal of organically bound sulfurs from carbonaceous fossil fuel such as petroleum and coal by cleaving bonds between carbon and sulfur atoms in the said sulfur-containing organic compounds, and a method for biological desulfurization using this strain at the room temperature and atmospheric pressure. Since Nocardia sp. CYKS2 (KCTC 0432 Bp) utilizes various organic sulfur compounds in fossil fuel besides dibenzothiophene as a sole sulfur source, the method for biological desulfurization employing the Nocardia strain has advantages over the conventional chemical methods as followings: The desulfurization can be carried out at a mild condition; the cost for installation and operation of equipments can be reduced; and, the desulfurization of highly complex organic sulfur compounds can be realized.
    Type: Grant
    Filed: March 2, 1999
    Date of Patent: March 6, 2001
    Assignee: Korea Advanced Institute of Science and Technology
    Inventors: Yong Keun Chang, Ho Nam Chang, Sung-Keun Rhee, Je Hwan Chang, Jung Hyun Sung