Patents by Inventor Yukio Ishigaki

Yukio Ishigaki 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: 6828799
    Abstract: A propagation delay time measuring method of measuring a propagation delay time of a test signal propagating along one of a first signal path serially connecting to the first signal path through which a semiconductor testing apparatus includes a driver and a comparator electrically connected to a device under test.
    Type: Grant
    Filed: August 22, 2003
    Date of Patent: December 7, 2004
    Assignee: Advantest Corporation
    Inventors: Koichi Higashide, Yukio Ishigaki
  • Publication number: 20040124852
    Abstract: A propagation delay time measuring method of measuring a propagation delay time of a test signal propagating along one of a first signal path and a second signal path serially connecting to the first signal path through which a semiconductor testing apparatus includes a driver and a comparator electrically connected to a device under test, the method includes: a first connecting step of connecting an end of the first path to the driver and the comparator; a first output step of outputting a test signal from the driver to the first path; a first reflect signal receiving step of receiving a test signal at the comparator, defined as a first reflect signal, reflected at another end of the first path; a first timing detecting step of detecting a timing, defined as a first timing; a second connecting step of connecting an end of the second path to another end of the first path; a second output step of outputting the test signal from the driver to the second path; a second reflect signal receiving step of receiving
    Type: Application
    Filed: August 22, 2003
    Publication date: July 1, 2004
    Inventors: Koichi Higashide, Yukio Ishigaki, Satoko Higashide
  • Patent number: 6688106
    Abstract: A waste-to-energy incineration system, in which the amount and heat value of exhaust gas largely changes in long and short periods, comprises an incinerator for burning waste, a boiler in the incinerator for generating steam with exhaust heat generated by the incinerator, a superheater for superheating steam generated in the boiler, a steam turbine driven by steam superheated by the superheater, a generator driven by the steam turbine, a fuel reformer for reforming source fuel, and a combustor burning fuel gas reformed by the fuel reformer and at least a part of exhaust gas led from the incinerator which is able to stably decompose generated dioxin in waste incineration exhaust gas.
    Type: Grant
    Filed: February 13, 2001
    Date of Patent: February 10, 2004
    Assignee: Hitachi, Ltd.
    Inventors: Tsutomu Okusawa, Kazuhito Koyama, Masahiko Yamagishi, Shigeo Hatamiya, Taiko Ajiro, Megumi Sunou, Yukio Ishigaki, Kenji Tokunaga
  • Patent number: 6442938
    Abstract: A waste-to-energy incineration system, in which the amount and the heat value of exhaust gas largely changes in long and a short periods, comprises an incinerator for burning waste, a boiler in the incinerator for generating steam with exhaust heat generated by the incinerator, a superheater for superheating steam generated in the boiler, a steam turbine driven by steam superheated by the superheater, a generator driven by the steam turbine, a fuel reformer for reforming source fuel, and a combustor burning fuel gas reformed by the fuel reformer and at least a part of exhaust gas led from the incinerator which is able to stably decompose generated dioxin in waste incineration exhaust gas.
    Type: Grant
    Filed: February 13, 2001
    Date of Patent: September 3, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Tsutomu Okusawa, Kazuhito Koyama, Masahiko Yamagishi, Shigeo Hatamiya, Taiko Ajiro, Megumi Sunou, Yukio Ishigaki, Kenji Tokunaga
  • Patent number: 6417682
    Abstract: A calibration method for calibrating a semiconductor testing apparatus before mounting semiconductor devices for performing a testing of electric characteristics thereof, the testing apparatus having a driver which generates and outputs a signal, and a socket with a plurality of terminals for receiving pins and transferring signals therethrough. The calibration method includes mounting a test board having a plurality of pins onto the socket and connecting each of the pins of the test board with a respective terminal of the socket, transferring the signal of the driver to the terminals of the test board, detecting the signal of the driver that has reached the test board, and setting an output timing of the signal of the driver based on the signal detected.
    Type: Grant
    Filed: May 19, 1999
    Date of Patent: July 9, 2002
    Assignee: Advantest Corporation
    Inventors: Toshikazu Suzuki, Hiroyuki Nagai, Noriyoshi Kozuka, Yukio Ishigaki, Shigeru Matsumura, Takashi Sekizuka, Hiroyuki Shiotsuka, Hiroyuki Hama, Eiichi Sekine
  • Patent number: 6369601
    Abstract: A propagation delay time measuring method is provided that is capable of easily and accurately measuring propagation delay times Tb and Tc of a drive signal path BL1 connected between a driver DR1 and an I/O pin of an IC under test 119 and a response signal path BL2 connected between a comparator CP2 and the I/O pin of the IC under test, respectively, in a short time, wherein the drive signal path and the response signal path are formed to have the same length, a pulse is supplied to the drive signal path from the driver, and a timing when the pulse is outputted from the response signal path is detected, thereby to measure a total propagation delay time given to the pulse when the pulse has propagated through the drive signal path and the response signal path based on the detected timing, and a time duration equal to 1/2 of the measured propagation delay time is calculated and determined to be a propagation delay time of each of the drive signal path and the response signal path.
    Type: Grant
    Filed: October 7, 1999
    Date of Patent: April 9, 2002
    Assignee: Advantest Corporation
    Inventor: Yukio Ishigaki
  • Publication number: 20010032468
    Abstract: A waste-to-energy incineration system, in which the amount and the heat value of exhaust gas largely changes in a long and a short periods, comprises an incinerator for burning waste, a boiler in the incinerator for generating steam with exhaust heat generated by the incinerator, a superheater for superheating steam generated in the boiler, a steam turbine driven by steam superheated by the superheater, a generator driven by the steam turbine, a fuel reformer for reforming source fuel, and a combustor burning fuel gas reformed by the fuel reformer and at least a part of exhaust gas led from the incinerator which are able to stably decompose generated dioxin, whereby it becomes possible to stably and almost completely decompose dioxin in waste incineration exhaust gas.
    Type: Application
    Filed: February 13, 2001
    Publication date: October 25, 2001
    Applicant: Hitachi, Ltd.
    Inventors: Tsutomu Okusawa, Kazuhito Koyama, Masahiko Yamagishi, Shigeo Hatamiya, Taiko Ajiro, Megumi Sunou, Yukio Ishigaki, Kenji Tokunaga
  • Publication number: 20010032451
    Abstract: A waste-to-energy incineration system, in which the amount and the heat value of exhaust gas largely changes in a long and a short periods, comprises an incinerator for burning waste, a boiler in the incinerator for generating steam with exhaust heat generated by the incinerator, a superheater for superheating steam generated in the boiler, a steam turbine driven by steam superheated by the superheater, a generator driven by the steam turbine, a fuel reformer for reforming source fuel, and a combustor burning fuel gas reformed by the fuel reformer and at least a part of exhaust gas led from the incinerator which are able to stably decompose generated dioxin, whereby it becomes possible to stably and almost completely decompose dioxin in waste incineration exhaust gas.
    Type: Application
    Filed: February 13, 2001
    Publication date: October 25, 2001
    Applicant: Hitachi, Ltd.
    Inventors: Tsutomu Okusawa, Kazuhito Koyama, Masahiko Yamagishi, Shigeo Hatamiya, Taiko Ajiro, Megumi Sunou, Yukio Ishigaki, Kenji Tokunaga
  • Patent number: 6282902
    Abstract: A waste-to-energy incineration system, in which the amount and heat value of exhaust gas largely changes in long and short periods, comprises an incinerator for burning waste, a boiler in the incinerator for generating steam with exhaust heat generated by the incinerator, a superheater for superheating steam generated in the boiler, a steam turbine driven by steam superheated by the superheater, a generator driven by the steam turbine, a fuel reformer for reforming source fuel, and a combustor burning fuel gas reformed by the fuel reformer and at least a part of exhaust gas led from the incinerator which is able to stably decompose generated dioxin in waste incineration exhaust gas.
    Type: Grant
    Filed: June 30, 1999
    Date of Patent: September 4, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Tsutomu Okusawa, Kazuhito Koyama, Masahiko Yamagishi, Shigeo Hatamiya, Taiko Ajiro, Megumi Sunou, Yukio Ishigaki, Kenji Tokunaga
  • Patent number: 6058856
    Abstract: A waste-to-energy incineration system, in which the amount and the heat value of exhaust gas changes during operation, includes an incinerator for burning waste, a boiler in the incinerator for generating steam with exhaust heat generated by the incinerator, and a superheater for superheating steam generated in the boiler. A steam turbine is provided which is driven by steam superheated by the superheater and a generator is driven by the steam turbine. A fuel reformer is provided for reforming source fuel. A combustor burning fuel gas reformed by the fuel reformer and at least a part of exhaust gas fed from the incinerator is provided which decomposes generated dioxin in waste incineration exhaust gas.
    Type: Grant
    Filed: April 1, 1998
    Date of Patent: May 9, 2000
    Assignee: Hitachi, Ltd.
    Inventors: Tsutomu Okusawa, Kazuhito Koyama, Masahiko Yamagishi, Shigeo Hatamiya, Taiko Ajiro, Megumi Sunou, Yukio Ishigaki, Kenji Tokunaga
  • Patent number: 6014863
    Abstract: A waste-to-energy incineration system, in which the amount and heat value of exhaust gas largely changes in long and short periods, comprises an incinerator for burning waste, a boiler in the incinerator for generating steam with exhaust heat generated by the incinerator, a superheater for superheating steam generated in the boiler, a steam turbine driven by steam superheated by the superheater, a generator driven by the steam turbine, a fuel reformer for reforming source fuel, and a combustor burning fuel gas reformed by the fuel reformer and at least a part of exhaust gas led from the incinerator which is able to stably decompose generated dioxin in waste incineration exhaust gas.
    Type: Grant
    Filed: October 28, 1997
    Date of Patent: January 18, 2000
    Assignee: Hitachi, Ltd.
    Inventors: Tsutomu Okusawa, Kazuhito Koyama, Masahiko Yamagishi, Shigeo Hatamiya, Taiko Ajiro, Megumi Sunou, Yukio Ishigaki
  • Patent number: 5532638
    Abstract: In a superconducting energy storage apparatus including an AC-DC converter unit, a superconducting coil, a quench protection unit and a mechanical type persistent current switch, a self-firing type thyristor switch is connected in parallel to the mechanical type persistent current switch to be first operated in the event of an occurrence of trouble in an associated electric power system, and a control unit generates an ON instruction signal for turning on the persistent current switch so as to immediately establish a persistent current mode.
    Type: Grant
    Filed: September 20, 1993
    Date of Patent: July 2, 1996
    Assignees: Hitachi, Ltd., Chubu Electric Power Co., Inc.
    Inventors: Morihiro Kubo, Yukio Ishigaki, Takeshi Itoh, Hirokazu Misawa
  • Patent number: 5218505
    Abstract: A superconducting coil system includes an excitation power source, a superconducting coil, a DC circuit breaker connected in series between the excitation power source and the superconducting coil to disconnect them when quenching occurs, a protective resistor connected in a parallel manner to the superconducting coil for dissipating the energy accumulated in the superconducting coil when the quenching occurs, and a switch provided as a bypass of the DC circuit breaker, the switch being closed during the normal operation to pass the energy from the excitation power source to the superconducting coil through a resistor and being opened when the quenching occurs.
    Type: Grant
    Filed: July 6, 1990
    Date of Patent: June 8, 1993
    Assignees: Hitachi, Ltd., Hitachi Engineering Service Co., Ltd.
    Inventors: Morihiro Kubo, Yukio Ishigaki
  • Patent number: 4920095
    Abstract: A superconducting energy storage device for storing electric power in superconducting magnets in the form of magnetic energy. The superconducting magnets are include a superconducting toroidal magnet and a superconducting solenoid magnet arranged to be inscribed in the inside of the superconducting toroidal magnet, the magnets being connected electrically in series to each other. Further, the superconducting magnets include a plurality of units, each of which is formed as a combination of the aforementioned toroidal and solenoid superconducting magnets, the units being piled up in the axial direction of the superconducting solenoid magnet. In the thus arranged device, electromagnetic force generated in the superconducting magnets can be supported without the necessity of firm bed rock, thereby eliminating the limitation in conditions of location of the energy storage device. Further, the plurality of energy storage units can be arranged effectively so that space can be saved.
    Type: Grant
    Filed: July 25, 1988
    Date of Patent: April 24, 1990
    Assignee: Hitachi, Ltd.
    Inventors: Yukio Ishigaki, Tadasi Sonobe