Patents by Inventor Natsuko Mizutani

Natsuko Mizutani 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: 5748953
    Abstract: A neighboring plural-character occurrence bitmap of a practical capacity capable of eliminating noises by hashing is realized, and a high speed full text search is realized equivalently, by greatly reducing the number of documents to be searched even if a search term constituted by a combination of English characters and words is used. Text data is segmented into words, and n-character strings at every (m+l)-th character positions are extracted from each word. A neighboring plural-character occurrence bitmap is created which stores data representing a presence of each neighboring plural-character string at a certain entry thereof. N-character strings at every (m+l)-th character positions are extracted from a search term and the neighboring plural-character occurrence bitmap is searched by using a search control program.
    Type: Grant
    Filed: May 18, 1995
    Date of Patent: May 5, 1998
    Assignee: Hitachi, Ltd.
    Inventors: Natsuko Mizutani, Atsushi Hatakeyama, Hisamitsu Kawaguchi, Katsumi Tada, Kanji Kato, Satoshi Asakawa
  • Patent number: 5745745
    Abstract: A text search method for structured documents and apparatus wherein structured document database to be searched is created by adding logical structure length information to logical structure discriminating information on the basis of a structured document constituted by a plurality of logical structures and logical structure discriminator information, and in searching the structured document database in accordance with an entered search key constituted by a logical structure and a search character string, the search of a logical structure other than the entered logical structure is skipped based upon the data length information.
    Type: Grant
    Filed: June 27, 1995
    Date of Patent: April 28, 1998
    Assignee: Hitachi, Ltd.
    Inventors: Katsumi Tada, Atsushi Hatakeyama, Hisamitsu Kawaguchi, Natsuko Mizutani, Kanji Kato, Satoshi Asakawa