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Byung Ki
Byung Ki Ahn, Seongnam KR
| Patent application number | Description | Published |
|---|---|---|
| 20100086450 | METHOD AND APPARATUS FOR PREPARING CATALYST SLURRY FOR FUEL CELLS - The present invention relates to a method and apparatus for preparing a catalyst slurry for fuel cells, in which nano-sized catalyst particles are dispersed uniformly at a high concentration and the adsorption force between the catalyst and ionomer is maximized. The resulting catalyst slurry is suitable for the manufacture of a membrane-electrode assembly (MEA) of a polymer electrolyte (or proton exchange) membrane fuel cell (PEMFC). | 04-08-2010 |
| 20110086292 | JOINING DEVICE FOR FUEL CELL STACK AND FUEL CELL STACK PROVIDED WITH THE SAME - The present invention features a fuel cell stack that preferably includes an electricity generating assembly having a plurality of unit cells that are suitably disposed one after another; a pair of end plates pressedly disposed respectively at upper and lower ends of the electricity generating assembly; and a joining device suitably engaging the end plates by a rope, where pressure is applied to the electricity generating assembly by means of tension of the rope, and the length and tension of the rope is suitably controlled. | 04-14-2011 |
| 20110129737 | COMPOSITE SEPARATOR FOR POLYMER ELECTROLYTE MEMBRANE FUEL CELL AND METHOD FOR MANUFACTURING THE SAME - The present invention provides a composite separator for a polymer electrolyte membrane fuel cell (PEMFC) and a method for manufacturing the same, in which a graphite foil prepared by compressing expanded graphite is stacked on a carbon fiber-reinforced composite prepreg or a mixed solution prepared by mixing graphite flake and powder with a resin solvent is applied to the cured composite prepreg such that a graphite layer is integrally molded on the outermost end of the separator. | 06-02-2011 |
Byung Ki Ahn, Seongnam Gyeonggi-Do KR
| Patent application number | Description | Published |
|---|---|---|
| 20110122991 | PINHOLE DETECTION SYSTEM OF FUEL CELL - The present invention features a pinhole detection system of a fuel cell that preferably includes a stage on which a fuel cell element unit is disposed to be detected, a drive portion that is configured to move the stage so as to rotate the fuel cell element unit, a X-ray source that is disposed at one side of the stage to apply X-ray to the fuel cell element unit that rotates, an image detector that detects X-ray penetrating the fuel cell element unit, and a computer tomography that reconstructs tormogram that is detected by the image detector to a three dimension. Preferably, the fuel cell element unit is rotated on the stage, X-ray is applied to the rotating unit to gain the tomogram thereof, and the tomogram is reconstructed to be a three-dimensional image through a computerized tomography (CT scanning) such that the pinhole formed within the unit can be effectively detected. | 05-26-2011 |
Byung Ki Han, Suwon-Si KR
| Patent application number | Description | Published |
|---|---|---|
| 20100317312 | APPARATUS AND METHOD FOR COMPENSATING FOR DC-OFFSET IN DIRECT CONVERSION RECEIVER OF WIRELESS COMMUNICATIONS SYSTEM - An apparatus and method of compensating for a direct voltage offset in a direct conversion receiver of a wireless communications system is provided. The apparatus includes a voltage control oscillator for generating a local oscillation signal having the same frequency as an input signal, a frequency converter for combining the input signal with the local oscillation signal, a first compensator for determining a first direct voltage offset generated due to a leaked local oscillation signal flowed into the frequency converter, for feeding back a magnitude of the determined first direct voltage offset to the frequency converter and for compensating for the first direct voltage offset, and a first register for storing a magnitude of direct voltage offset for a first variable gain amplifier, wherein the first variable gain amplifier is positioned in a rear end of the frequency converter, connected to the first register, and performs a modem associated offset compensation using a magnitude of direct voltage offset stored in the first register. | 12-16-2010 |
Byung Ki Moon, Seoul KR
| Patent application number | Description | Published |
|---|---|---|
| 20100074076 | WOBBLE SIGNAL DETECTOR INCLUDING THE SIGNAL PROCESSOR, OPTICAL DISK APPARATUS INCLUDING THE WOBBLE SIGNAL DETECTOR AND READ-WRITE OPTICAL DISK DRIVE INCLUDING THE WOBBLE SIGNAL DETECTOR - A signal processor includes an operational amplifier performing an operation on first and second signals, and amplifying a signal resulting from the operation based on an amplification control signal to remove an offset voltage, a buffer buffering an output signal of the operational amplifier and outputting a result of the buffering as differential signals, an automatic gain amplifier automatic gain amplifying the differential signals output from the buffer and outputting an automatic gain amplified signal as a single ended signal, a level shifter level shifting a level of the single ended signal including the offset voltage and outputting a level shifted signal as level shifted differential signals, and an offset voltage compensation unit converting a difference between the level shifted differential signals to a digital signal, detecting the offset voltage based on the digital signal, and outputting the amplification control signal to compensate for the detected offset voltage. | 03-25-2010 |
Byung Ki Park, Daejeon KR
| Patent application number | Description | Published |
|---|---|---|
| 20090186225 | Flaky Alpha-Alumina Crystal and a Method of Its Preparation - The present invention relates to a flaky α-alumina crystal and a preparation method thereof. More particularly, the present invention relates to a flaky α-alumina crystal comprising aluminum oxide and zinc oxide, which is prepared by hydrolyzing an aluminum precursor solution containing a water-soluble flux and a zinc precursor solution to obtain a gel mixture and aging, drying, calcining and crystallizing it under a specific reaction condition, and a preparation method thereof. Since the flaky α-alumina crystal of the present invention has a thickness of less than 0.5 μm, an average particle diameter of at least 15 μm and an aspect ratio of at least 50, it is useful as high-quality pearlescent pigment material and filler for ceramic materials. | 07-23-2009 |
| 20090320719 | PEARLESCENT PIGMENTS WITH LARGE ASPECT RATIO AND A METHOD OF THEIR PREPARATION - The present invention relates to a pearlescent pigment with large aspect ratio and a method of their preparation, and particularly to pearlescent pigments prepared by coating a metal or metal precursor on the flaky alpha-alumina crystals obtained by using an aluminum precursor aqueous solution and a zinc precursor aqueous solution as main ingredients. The crystals herein has an average particle thickness of 0.5 μm or less, an average particle diameter of 15 μm or higher and a large aspect ratio of 50 or higher, thereby being superior in gloss. The crystals show metal colors and interference colors of silver, gold, red, purple, blue and green. | 12-31-2009 |
| 20100015445 | FLAKY ALPHA-ALUMINA CRYSTALS WITH LARGE ASPECT RATIO AND A PREPARATION METHOD OF THE SAME - The present invention relates to flaky alpha-alumina crystals with large aspect ratio and its preparation method, and particularly to flaky alpha-alumina crystals comprising aluminum oxide, zinc oxide and tin oxide, which are prepared by obtaining a mixed gel which are prepared by obtaining a mixed gel by means of hydrolysis of an aqueous aluminum precursor solution comprising aqueous flux, aqueous zinc precursor solution and tin precursor aqueous solution, followed by aging, drying and crystallization processes. The crystals herein have an average particle thickness of 0.5 um or less, an average particle diameter of 30 μm or higher and an aspect ratio of 100 or higher, thus being useful as a substrate of high quality pearlescent pigments, an abrasive, ceramic material and a filling material. | 01-21-2010 |
Byung Ki Son, Ulsan-City KR
| Patent application number | Description | Published |
|---|---|---|
| 20100109222 | CLAMP DEVICE - A clamp device for clamping a panel regardless of the panel's shape may include an air conduit, an air supplying unit that is communicated with the air conduit for selectively supplying air thereto and a tube that is connected with the air conduit to communicate therewith and expanded outwardly. | 05-06-2010 |