Patents by Inventor Kazuhiko Ohmachi

Kazuhiko Ohmachi 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: 5317727
    Abstract: In a data base processing method including a central processing unit for analyzing a plurality of queries made from a plurality of users so as to determine an internal processing procedure with respect to a data base, and for performing the internal processing procedure; a secondary storage for storing data capable of being shared by each user; and, an input/output controlling processing unit including at least one cache storage, for controlling a transfer of a plurality of records which are required for input/output processing operations between the central processing unit and secondary storage.
    Type: Grant
    Filed: May 17, 1989
    Date of Patent: May 31, 1994
    Assignees: Hitachi Software Engineering Co., Ltd., Hitachi, Ltd.
    Inventors: Masashi Tsuchida, Kazuhiko Ohmachi, Toshio Honma, Yasuhiro Imai, Nobuo Kawamura
  • Patent number: 5091852
    Abstract: A method for processing a database for analyzing a query to the database from a user to determine an internal processing procedure therefor and executing it comprises the steps of preparing single or a plurality of internal processing procedures based on analysis result of the query including a variable inputted in a preprocess step and statistical information of a database system, selecting an optimum one of the internal processing procedures based on a value substituted for the variable of the query in a query execution stage and the statistical information of the database system, and executing the query in accordance with the selected internal processing procedure.
    Type: Grant
    Filed: January 25, 1989
    Date of Patent: February 25, 1992
    Assignee: Hitachi, Ltd.
    Inventors: Masashi Tsuchida, Kazuhiko Ohmachi
  • Patent number: 5023774
    Abstract: After passing through the process in which the number of one page I/O requests generated in a certain unit time period, the number of multiple pages I/O requests, and the number of pages required at each of the multiple pages I/O request are input, the quantity of the I/O requests generated in the above-described unit time period is calculated in accordance with the thus-input values. The unit (the number of pages) for a multiple pages I/O actually performed by one time operation of the I/O control device corresponding to the multiple pages I/O request from users is determined in accordance with the user's instruction or specific criterion for the system based on the result of the above-described calculation, the performance of the CPU, the performance of the I/O control device, the performance of the DASD (Direct Access Storage Decive), and to which DASD each of I/O requests corresponds.
    Type: Grant
    Filed: November 8, 1988
    Date of Patent: June 11, 1991
    Assignees: Hitachi Software Engineering Co., Ltd., Hitachi, Ltd.
    Inventors: Naohumi Sakai, Masashi Tsuchida, Kazuhiko Ohmachi, Yasuhiro Imai, Toshio Honma
  • Patent number: 4967341
    Abstract: A set of sorted columns of one table stored in a DB machine are binary-searched by a hardware in synchronism with data transfer when another table is read from a disk unit, to select a row to be joined. Where a key word sequence to be searched is stored in ascending or descending order, determination of a maximum address in an area in which key words smaller than a search key are stored and determination of a maximum address in an area in which the key words smaller than or equal to the search key are stored are parallelly executed to determine the store range in one searching.
    Type: Grant
    Filed: October 6, 1989
    Date of Patent: October 30, 1990
    Assignee: Hitachi, Ltd.
    Inventors: Akira Yamamoto, Tadashi Ohsone, Masashi Tsuchida, Hiroyuki Kitajima, Kazuhiro Satoh, Yoshiaki Yamashita, Nobuhiro Taniguchi, Kazuhiko Ohmachi, Shinichi Fukushima
  • Patent number: 4542458
    Abstract: A method of assinging software resources such as files and programs to memory devices is disclosed which uses first storage for storing therein the access frequency to a memory device for causing each type of service request to utilize each of software resources and second storage for storing therein the processing speed, allowable utilization and storage capacity of each of memory devices and in which the allocation of each of said software resources to the memory devices is determined on the basis of information stored in the first and second storages so that a total time taken to access the memory devices is minimized while being restricted by the allowable utilization and storage capacity of each memory device.
    Type: Grant
    Filed: May 18, 1983
    Date of Patent: September 17, 1985
    Assignee: Hitachi, Ltd.
    Inventors: Hiroyuki Kitajima, Kazuhiko Ohmachi, Mitsuru Doki, Junichi Kazama, Hidekazu Kanao
  • Patent number: 4495570
    Abstract: A distributed processing system having a plurality of processors and/or terminals at a plurality of locations is provided with a processing request allocator which includes a device for storing the waiting time at each processor or terminal for beginning the execution of a service request as well as a device for storing the delay in communication from each location of a processor or terminal to each other processor or terminal in the system. The processing request allocator has a device for calculating the sums of the waiting time and delay for each route through the system where a processing request from a first location is executed by a predetermined processor and the processing result is sent to a second location within the system, and a device is provided for determining the minimum value of these sums to identify the processor or terminal to which the service request is to be allocated.
    Type: Grant
    Filed: January 7, 1982
    Date of Patent: January 22, 1985
    Assignee: Hitachi, Ltd.
    Inventors: Hiroyuki Kitajima, Kazuhiko Ohmachi