Patents by Inventor K. Choi

K. 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).

  • Patent number: 5343746
    Abstract: A humidity sensing apparatus is operated by an AC power supply. The humidity sensing apparatus comprises a humidity sensing section including a humidity sensor and a divider resistor connected in parallel to the humidity sensor; a humidity sensor operating section for supplying the humidity sensor with an AC voltage within predetermined voltage levels; and, a humidity signal converting section including diodes, condensers and resistors. The humidity signal converting section converts the AC humidity signal output from the humidity sensing section into a corresponding DC humidity signal by selecting the time constants of the pair of condenser-resistor circuits and then supplies the peripheral digital circuits with the converted signals.
    Type: Grant
    Filed: February 22, 1993
    Date of Patent: September 6, 1994
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Jin K. Choi
  • Patent number: 5336673
    Abstract: The present invention relates to novel cephalosporins of the formula (I); ##STR1## wherein, R.sub.1 represents a C.sub.1 .about.C.sub.4 alkyl group or ##STR2## wherein, R.sub.2 and R.sub.3, independently, represent hydrogen or a C.sub.1 .about.C.sub.3 alkyl group and R.sub.4 represents hydrogen or a C.sub.1 .about.C.sub.4 alkyl group;R.sub.1a represents hydrogen or an amino-protecting group;Q represents CH or N; andthe formula ##STR3## represents a saturated or unsaturated heterocyclic group which contains 1 to 4 nitrogen atoms of which one is substituted with an amino group to form quaternary ammonium, and oxygen or sulfur, or a fused heterocyclic group thereof formed together with a substituted or unsubstituted benzene or an optional heterocyclic group, or a pharmaceutically acceptable salt thereof, to processes for preparing the same and to a pharmaceutical composition containing the same as an active ingredient.
    Type: Grant
    Filed: February 26, 1992
    Date of Patent: August 9, 1994
    Assignee: Dae Woong Pharmaceutical Co., Ltd.
    Inventors: Chi J. Moon, Sae C. Park, Myoung G. Kim, Sea H. Oh, Seong S. Yim, Nam J. Park, Young K. Choi, Moo J. Sung
  • Patent number: 5334746
    Abstract: A process for the preparation of .alpha.-L-aspartyl-L-phenylalanine methyl ester in high yield, which comprises the steps of esterifying L-phenylalanine with methanol while undergoing continuous evaporation to remove the water formed during esterification, coupling the produced L-phenylalanine methyl ester with N-formyl-L-aspartic anhydride, deformylating the produced N-formyl-L-aspartyl-L-phenylalanine methyl ester, crystallizing the formed .alpha.-L-aspartyl-L-phenylalanine methyl ester as .alpha.-L-aspartyl-L-phenylalanine methyl ester hydrochloric acid salt, recovering the first .alpha.-L-aspartyl-L-phenylalanine methyl ester hydrochloric acid salt, esterifying .alpha.-L-aspartyl-L-phenylalanine in the filtrate to produce the second .alpha.-L-aspartyl-L-phenylalanine methyl ester, and combining the first and second .alpha.-L-aspartyl-L-phenylalanine methyl ester product.
    Type: Grant
    Filed: December 6, 1993
    Date of Patent: August 2, 1994
    Assignee: Miwon Co., Ltd.
    Inventors: Kyung S. Choi, Dae K. Joo, Min S. Han, E Nam Hwang, Hong K. Choi
  • Patent number: 5317304
    Abstract: An anti-theft device and method includes a motion sensor for detecting motion and generating signals. The present invention also includes an anti-tamper mechanism for sounding an alarm when the apparatus is tampered with. The motion sensor and anti-tamper sensor are coupled to a computer which is in stand-by mode most of the time to conserve energy. When signals are sent to the computer, its software interprets the signals and generates an alarm when the computer determines that at least one of a plurality of predetermined motion values are met. The predetermined motion values include frequency of motion, duration of motion and intensity of motion. The alarm is sounded in increments of varying duration according to the interpretation of the signals by the software, thus providing warning signals and full alarms.
    Type: Grant
    Filed: October 23, 1991
    Date of Patent: May 31, 1994
    Assignee: Sonicpro International, Inc.
    Inventor: Alexander K. Choi
  • Patent number: 5315608
    Abstract: An eye-safe short pulse room-temperature solid state laser emitting at about 2.1 microns is optically pumped by diode lasers emitting at about 1.9 microns Absorption spectra of Ho ions in YAG (Yttrium Aluminum Garnet) and YLF (Yttrium Lithium Fluoride) host crystals are described. Optical pumping is performed by high-power diode lasers emitting at about 1.91 microns consisting of a GaInAsSb/AlGaAsSb quantum-well active region and AlGaAsSb cladding layers grown on GaSb substrates.
    Type: Grant
    Filed: July 17, 1992
    Date of Patent: May 24, 1994
    Assignee: Massachusetts Institute of Technology
    Inventors: Hong K. Choi, Stephen J. Eglash, Tso Y. Fan, C. David Nabors
  • Patent number: 5254829
    Abstract: A water-cooled plasma torch specially designed to drill into a refractory material is used in a method for opening a tap hole closed by a plug in a wall of a furnace. This method which is particularly well adapted for robotization, includes the step of melting and breaking up the plug closing the tap hole by means of a jet of swirling gas of high speed and high temperature, generated by the plasma torch. The main advantage of this method is that the stream of plasma gas leaving the torch has a well defined outline ensuring precise and reproducible tapping of the plug and, as a result, efficient closing of the tap hole with a new plug after the furnace has been emptied.
    Type: Grant
    Filed: December 5, 1990
    Date of Patent: October 19, 1993
    Assignee: Hydro Quebec
    Inventors: Michel G. Drouet, Jean Meunier, Hyun K. Choi
  • Patent number: 5251225
    Abstract: A GaInAsSb quantum-well laser for highly efficient conversion of input energy to output infrared light is described. The laser consists of an MBE grown active region formed of a plurality of GaInAsSb quantum-well layers separated by AlGaAsSb barrier layers. The active region is sandwiched between AlGaAsSb cladding layers in which the Al content is greater than the Al content in the barrier layers.
    Type: Grant
    Filed: May 8, 1992
    Date of Patent: October 5, 1993
    Assignee: Massachusetts Institute of Technology
    Inventors: Stephen J. Eglash, Hong K. Choi
  • Patent number: 5242944
    Abstract: The present invention provides novel phenylacetamide derivatives having the following formula ##STR1## wherein: X is a hydrogen, halogen, hydroxy, nitro, amino, R.sup.1, NR.sup.1 R.sup.2, NHR.sup.1 or OR.sup.1 wherein R.sup.1 and R.sup.2 are an optionally substituted C.sub.1-8 alkyl, cycloalkyl or benzyl group, respectively; Y, which may be the same or different when p is greater than 1, is a hydrogen, halogen, methylenedioxy, hydroxy, trifluoromethyl, R.sup.3 or OR.sup.3 wherein R.sup.3 is an optionally substituted C.sub.1-8 alkyl or benzyl group;n is an integer from 1 to 6; andp is an integer from 1 to 5; and pharmaceutically acceptable salts thereof which have powerful analgesic and anti-inflammatory activities.The invention also provides processes for preparing these compounds and pharmaceutical compositions containing them as an active ingredient.
    Type: Grant
    Filed: April 13, 1992
    Date of Patent: September 7, 1993
    Assignee: Korea Research Institute of Chemical Technology
    Inventors: No S. Park, Deok C. Ha, Joong K. Choi, Hyun S. Kim, Mi S. Hong, Hee J. Lim, Kwang S. Lee
  • Patent number: 5216684
    Abstract: A strained quantum-well diode laser with an AlInGaAs active layer and AlGaAs cladding and/or confining layers on a GaAs substrate is provided. AlInGaAs/AlGaAs lasers can be configured in laser geometries including ridge, waveguide, buried heterostructure, oxide-defined, proton-defined, narrow-stripe, broad-stripe, coupled-stripe and linear arrays using any epitaxial growth technique. Broad-stripe devices were fabricated in graded-index separate confinement heterostructures, grown by organometallic vapor phase epitaxy on GaAs substrates, containing a single Al.sub.y In.sub.x Ga.sub.l-x-y As quantum well with x between 0.14 and 0.12 and y between 0.05 and 0.17. With increasing Al content, emission wavelengths from 890 to 785 nm were obtained. Threshold current densities, J.sub.th 's, less than 200 A cm.sup.-2 and differential quantum efficiencies in the range 71 to 88 percent were observed.
    Type: Grant
    Filed: September 7, 1990
    Date of Patent: June 1, 1993
    Assignee: Massachusetts Institute of Technology
    Inventors: Christine A. Wang, James N. Walpole, Hong K. Choi, Joseph P. Donnelly
  • Patent number: 5215218
    Abstract: The present invention relates to an improved toothpaste dispensing apparatus which includes a housing having a grasping assembly for holding the toothpaste container, a guide and brace assembly for supporting the toothpaste container and a nozzle assembly including a capping mechanism for dispensing the toothpaste. A drive assembly is mounted within the housing and drives a carriage assembly for squeezing the toothpaste container. A control system is also included for activating the drive assembly and for automatic reversal of the drive assembly.
    Type: Grant
    Filed: September 5, 1991
    Date of Patent: June 1, 1993
    Inventor: Min K. Choi
  • Patent number: 5193088
    Abstract: A high speed ATM cell synchronizing switching apparatus is disclosed, and the apparatus includes: a plurality of ATM cell inputting circuits 1 for receiving optical ATM signals; a routing control circuit 2 for receiving address information; a cell gate circuit 3 for transmitting the inputted cells synchronously; a switching information tabling circuit 4 for switching the switching information; and a switching matrix circuit 5 for receiving and outputting the switching control information and the cell data information.
    Type: Grant
    Filed: June 24, 1991
    Date of Patent: March 9, 1993
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Jun K. Choi, Mun K. Choi, Kyung S. Kim, Tae S. Jeong, Young S. Shin
  • Patent number: 5128766
    Abstract: A multiple television screen processing circuit having the teletext function. The circuit comprises a TV video signal generator for producing a TV video signal; a PIP signal generator for producing a PIP signal, an ON screen display signal generator for producing an ON screen display signal, and a teletext signal generator for producing a teletext signal, each of them being controlled by a microcomputer; a selection controller for combing logically said selection-controlling signals; a signal selector for selecting and outputting, under the control of the selection-controlling signals and the output signal of the selection controller, the TV video signal, the PIP signal, the ON screen display video signal or the teletext signal; an amplifier for amplifing the output signal of the signal selector; and a Braun tube for displaying the output signal of the amplifier.
    Type: Grant
    Filed: November 27, 1990
    Date of Patent: July 7, 1992
    Assignee: Goldstar Co., Ltd.
    Inventor: Suk K. Choi
  • Patent number: 5050773
    Abstract: The present invention relates to a toothpaste dispensing apparatus which includes a housing having an adaptable nozzle at the top of the housing and two adaptable grasping assemblies located within the housing for holding the toothpaste container. A drive assembly is mounted within the housing and drives a carriage for squeezing along the length of the toothpaste container. A control system is also included for activating the drive assembly and for automatic reversal of the drive assembly.
    Type: Grant
    Filed: February 12, 1990
    Date of Patent: September 24, 1991
    Inventor: Min K. Choi
  • Patent number: 5017754
    Abstract: Disclosed is a plasma reactor for use to treat ores or other material at a very high temperature in order to physically or chemically transform the same. The reactor comprises a vertical, electrically insulated sleeve disposed at the upper end with a hollow torch of a conventional structure, for use to generate a plasma column. A gas is tangentially injected into the torch to create a vortex inside the same. The material to be treated is dropped, in powder form, vertically downward inside the sleeve from the upper end thereof, beside the hollow torch, so as to form a substantially uniform cylindrical curtain of particles falling down into the sleeve. The particles that are centrifugally projected against the internal wall of the sleeve by the vortex escaping from the hollow torch, entirely cover the internal wall of the sleeve and shield, while simultaneously being treated by heat generated by the plasma arc column.
    Type: Grant
    Filed: August 29, 1989
    Date of Patent: May 21, 1991
    Assignee: Hydro Quebec
    Inventors: Michel G. Drouet, Hyun K. Choi
  • Patent number: 4859278
    Abstract: This invention relates to a method of fabricating high resistive loads utilizing a single level polycide process in very large scale integrated circuits. By etching away a top silicide layer which exposes an underlying polysilicon layer and then implanting with a heavy dose of boron, a high resistive load on the integrated circuit is formed. Very often the highly resistive polysilicon load is implemented as a second polysilicon layer, which increases the process complexity vastly. This invention discloses the use of only one polycide layer to implement both the low resistive gate and interconnect and the high resistive polysilicon load needed to implement certain circuit functions.
    Type: Grant
    Filed: August 11, 1988
    Date of Patent: August 22, 1989
    Assignee: Xerox Corporation
    Inventor: Francis K. Choi
  • Patent number: 4832699
    Abstract: Filament nylon 6 and 66 fabrics are dyed in a multi-step continuous aqueous dyeing process. Uniformly dyed fabrics having a high degree of fiber bundle penetration result.
    Type: Grant
    Filed: December 17, 1987
    Date of Patent: May 23, 1989
    Assignee: Burlington Industries, Inc.
    Inventors: M. K. Choi, Ernest J. Russell
  • Patent number: 4812140
    Abstract: High-tenacity nylon fabrics are dyed in a multi-step continuous aqueous dyeing process. Uniformly dyed fabrics having a high degree of fiber bundle penetration result.
    Type: Grant
    Filed: July 15, 1987
    Date of Patent: March 14, 1989
    Assignee: Burlington Industries, Inc.
    Inventors: Ernest J. Russell, M. K. Choi
  • Patent number: 4809867
    Abstract: A door opening/closing device for use in electronic appliances such as a VCR, a TV set and audio products, which can easily open the door of an electronic appliance simply by pushing a locking-loosening button. The device comprises a door to open and close the front opening of the front panel of an electronic appliance and a rack gear formed in the inner side of the door, a pinion gear engaged with the rack gear and provided with a pair of integrated interlocking gears, a pair of driving gears engaged with the interlocking gears and provided with a spiral spring wound onto its axis, a locker for locking a catching projection of the door, a locking-loosening interlocking lever supported by a horizontal axis with its lower part coming into contact with the interlocking part of the door and a locking-loosening button for opening the door by pushing it.
    Type: Grant
    Filed: December 21, 1987
    Date of Patent: March 7, 1989
    Assignee: Goldstar Co., Ltd.
    Inventor: Dong K. Choi
  • Patent number: 4774205
    Abstract: Monolithic integration of Si MOSFETs and gallium arsenide MESFETs on a silicon substrate is described herein. Except for contact openings and final metallization, the Si MOSFETs are first fabricated on selected areas of a silicon wafer. CVD or sputtering is employed to cover the wafer with successive layers of SiO.sub.2 and Si.sub.3 N.sub.4 to protect the MOSFET structure during gallium arsenide epitaxy and subsequent MESFET processing. Gallium arsenide layers are then grown by MBE or MOCVD or VPE over the entire wafer. The gallium arsenide grown on the bare silicon is single crystal material while that on the nitride is polycrystalline. The polycrystalline gallium arsenide is etched away and MESFETs are fabricated in the single crystal regions by conventional processes. Next, the contact openings for the Si MOSFETs are etched through the Si.sub.3 N.sub.4 /SiO.sub.2 layers and final metallization is performed to complete the MOSFET fabrication.
    Type: Grant
    Filed: June 13, 1986
    Date of Patent: September 27, 1988
    Assignee: Massachusetts Institute of Technology
    Inventors: Hong K. Choi, Bor-Yeu Tsaur, George W. Turner
  • Patent number: 4602822
    Abstract: Disclosed is an apparatus for varying eccentrically or centrically the shaft of the bicycle wheel in order that the bicycle can run up and down like horseback riding beside regular level riding. The apparatus has an eccentric hub including a shaft housing formed integrally in eccentric position between two hub discs having an opening and a shaft penetrated through said shaft housing, two circular supporting plates coupled rigidly each other by three connecting rods to reserve revolvably said eccentric hub therebetween, each which has a hub disc housing formed in its eccentric position said hub disc housing has a relatively large hole on its centric portion to exposure the shaft and also a plurality of openings corresponding to different eccentric positions on its circumference of circle, and a resettable spring loaded rod for locking the eccentric hub between the hub disc housings of the circular supporting plates by passing through the openings in alignment with each other.
    Type: Grant
    Filed: September 7, 1984
    Date of Patent: July 29, 1986
    Inventors: Joo H. Kim, Rack K. Choi