Patents by Inventor Han S. Uhm

Han S. Uhm 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: 5949835
    Abstract: A steady-state source of neutrons is produced within an electrically grounded and temperature controlled chamber confining tritium or deuterium plasma at a predetermined density to effect implantation of ions in the surface of a palladium target rod coated with diffusion barrier material and immersed in such plasma. The rod is enriched with a high concentration of deuterium atoms after a prolonged plasma ion implantation. Collision of the deuterium atoms in the target by impinging ions of the plasma initiates fusion reactions causing emission of neutrons during negative voltage pulses applied to the rod through a high power modulator. The neutrons are so generated at a relatively high dose rate under optimized process conditions.
    Type: Grant
    Filed: July 1, 1991
    Date of Patent: September 7, 1999
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: Han S. Uhm, Woodrow W. Lee
  • Patent number: 5942206
    Abstract: Isotopic hydrogen enrichment in a soluble metal is achieved through temperature gradient effects by applying a heat source and a heat sink to two spaced regions of the metal within which isotopic hydrogen atoms are absorbed and enclosed by a diffusion-barrier material. The temperature gradient so created forces the atoms of hydrogen in the hot region to migrate into the cold region, resulting in higher isotopic hydrogen density in the cold region. Discharge of the absorbed isotopic hydrogen is prevented effectively by the diffusion-barrier material.
    Type: Grant
    Filed: August 23, 1991
    Date of Patent: August 24, 1999
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: Han S. Uhm, Woodrow W. Lee
  • Patent number: 5830328
    Abstract: The burning of material, including fuel and/or waste products, is performed ithin an incineration chamber heated above room-temperature while being supplied with high-power microwave radiation under conditions generating a plasma through which oxidation is enhanced to eliminate contaminants from the gaseous emission discharged from the incineration chamber.
    Type: Grant
    Filed: June 24, 1996
    Date of Patent: November 3, 1998
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventor: Han S. Uhm
  • Patent number: 5773934
    Abstract: Nonlinear current modulation of a relativistic electron beam is achieved by ts propagation without interruption through a resistive wall type of drift tube assembly within a klystron amplifier. Maximized beam current modulation is thereby attained for a beam propagation distance within a shortened drift tube.
    Type: Grant
    Filed: April 3, 1996
    Date of Patent: June 30, 1998
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventor: Han S. Uhm
  • Patent number: 5581154
    Abstract: Nonlinear current modulation of a relativistic electron beam is achieved by ts propagation without interruption through a resistive wall type of drift tube assembly within a klystron amplifier. Maximized beam current modulation is thereby attained for a beam propagation distance within a shortened drift tube.
    Type: Grant
    Filed: April 10, 1995
    Date of Patent: December 3, 1996
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventor: Han S. Uhm
  • Patent number: 5478532
    Abstract: A weakly ionized plasma is generated by continuous high-power microwave win a dielectric cavity positioned in a slow waveguide. Contaminated air under atmospheric pressure is exposed to the plasma within the waveguide cavity for a limited saturation time controlled by inflow at a regulated flow rate. During such limited saturation time, the contaminated air is purified by sequential ionization and recombination under an electron temperature resulting in a microwave discharge plasma dominated by atomic oxygen at a relatively high saturation density level together with atomic nitrogen at a relatively low density level.
    Type: Grant
    Filed: May 10, 1995
    Date of Patent: December 26, 1995
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventor: Han S. Uhm
  • Patent number: 5468356
    Abstract: A weakly ionized plasma is generated by continuous high-power microwave win a dielectric cavity positioned in a slow waveguide. Contaminated air under atmospheric pressure is exposed to the plasma within the waveguide cavity for a limited saturation time controlled by inflow at a regulated flow rate. During such limited saturation time, the contaminated air is purified by sequential ionization and recombination under an electron temperature resulting in a microwave discharge plasma dominated by atomic oxygen at a relatively high saturation density level together with atomic nitrogen at a relatively low density level.
    Type: Grant
    Filed: August 23, 1991
    Date of Patent: November 21, 1995
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventor: Han S. Uhm
  • Patent number: 5434583
    Abstract: Signal antennae are mounted on the casing wall between forward nose and r tail ends of an aerospace launched vehicle for radio communication through a radiation conducting sheath of plasma formed thereon by atmospheric ionization during descent of the vehicle along a non-gliding reentry path. The reentry path is maintained by vehicle guidance at a steep angle in response to data transmitted to the antennae through the radiation conducting sheath having a plasma content minimized by cooling which is thereby maintained in complete surrounding relation to the vehicle and modulated to enhance data transmission during the entire duration of vehicle descent.
    Type: Grant
    Filed: May 23, 1994
    Date of Patent: July 18, 1995
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: Philip W. Hesse, Han S. Uhm, Joon Choe
  • Patent number: 5410575
    Abstract: Fast neutrons from a moving source are thermalized by travel through water to a soil embedded body of nitrogen-rich material causing emission of gamma rays therefrom. Emitted gamma rays are detected at a location adjacent the neutron source for measurement of radiation energy from which location of nitrogen-rich materials in the soil is mapped, based on a predetermined signature energy level of the measured radiation.
    Type: Grant
    Filed: January 27, 1993
    Date of Patent: April 25, 1995
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventor: Han S. Uhm
  • Patent number: 5386177
    Abstract: A body of dense plasma is established within a short drift tube of a klysn amplifier between input and output resonator cavities thereof to support current modulation of microwave energy by interaction with an electron beam propagated through the drift tube. The plasma is confined to a column radially spaced from the electron beam for two-stream interaction enabling enhancement of current modulation under simultaneous high-power and high frequency operation.
    Type: Grant
    Filed: May 20, 1993
    Date of Patent: January 31, 1995
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventor: Han S. Uhm
  • Patent number: 5283530
    Abstract: A bore formed within a body of material storing a magnetic field at a sattion level, establishes a linear path along which an electron beam is focussed after the bore is ionized to form a plasma channel therein. The driving current of the beam is sharply decreased to cause simultaneous decay of the stored magnetic field from a saturation level inducing an electric field concentrated in the plasma channel to accelerate travel of trailing electrons in the beam with a high accelerating gradient.
    Type: Grant
    Filed: September 12, 1991
    Date of Patent: February 1, 1994
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventor: Han S. Uhm
  • Patent number: 5142250
    Abstract: Conversion of electron beam energy into high power microwave energy is efted within the cavity of a Klystron device to which the electron beam is accelerated from a continuous supply source through an ion focussing channel. Ion focussing is achieved by establishment of a preionized background plasma within the channel to modulate the current of the electron beam in response to wake field effects and cause bunching of the electron beam during propagation to the Klystron device.
    Type: Grant
    Filed: January 14, 1992
    Date of Patent: August 25, 1992
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: Han S. Uhm, Khanh T. Nguyen
  • Patent number: 5051659
    Abstract: Annular arrangements of thermionic filaments adjacent opposite axial ends a chamber within which argon gas at low presure is confined, generate steady state plasma with uniformity by low energy emission of gas ionizing electrons from the filaments. The ionizing electrons and plasma generated are axially confined between grids at the axial ends of the chamber and radially confined by a low intensity magnetic field generated by an external magnetic coil.
    Type: Grant
    Filed: January 30, 1991
    Date of Patent: September 24, 1991
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: Han S. Uhm, Joel D. Miller, Ralph F. Schneider, Daniel J. Weidman
  • Patent number: H2102
    Abstract: Contaminants within the gaseous emission discharged from an incinerator are eliminated during passage in parallel through reactor chambers by chemical reaction induced during exposure to plasma generated within said chambers. The plasma is generated by corona-discharge breakdown of electric fields established about electrodes within the reactor chambers upon supply thereto of electrical pulse voltage exceeding a critical field breakdown value inversely proportional to a high chamber temperature of the gaseous emission under atmospheric pressure within the reactor chambers.
    Type: Grant
    Filed: May 29, 1998
    Date of Patent: May 4, 2004
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventor: Han S. Uhm