Patents by Inventor Takaharu Nagumo

Takaharu Nagumo 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: 5467292
    Abstract: A logical operation method for evaluating a train of output data to be obtained when a plurality of input patterns are successively applied to a memory element whose output value depends upon a sequence of input values. For each of the plurality of patterns in time series, the method decides whether or not the pertinent pattern is a holding pattern which means that the output value of the memory element depends upon a preceding pattern. Subsequently, the method evaluates a first train of data which consists of flags each indicating whether or not the respective pattern is the holding pattern, and a second train of data which consist of a predetermined logical values for the holding patterns and output logical values of the memory element for the non-holding patterns. Finally, the method subjects the first and second trains of data to operations in parallel by the use of a parallel arithmetic unit, thereby obtaining the train of output data of the memory element in parallel.
    Type: Grant
    Filed: June 9, 1992
    Date of Patent: November 14, 1995
    Assignee: Hitachi, Ltd.
    Inventors: Hiroo Watai, Takao Nishida, Takaharu Nagumo, Masahiko Nagai
  • Patent number: 5184308
    Abstract: A logic circuit to be an object for fault simulation is logically modified into a logic circuit configuration using logic gates of a predetermined basic gate form. Pin management data indicative of a correspondence of pins of the logic gates to a position of fault assumption of each of the pins prior to logic modification is formed. Logic simulation is then performed by injecting a fault logic value into the position of fault assumption of each of the pins of the gate of the logic circuit subsequent to the logic modification corresponding to each of the pins prior to the logic modification with reference to the pin management data, thereby implementing a fault simulation for detecting the fault of the logic circuit.
    Type: Grant
    Filed: October 1, 1990
    Date of Patent: February 2, 1993
    Assignee: Hitachi, Ltd.
    Inventors: Masahiko Nagai, Hiroo Watai, Takaharu Nagumo, Kaoru Moriwaki