Patents by Inventor O Sam Nakagawa

O Sam Nakagawa 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: 6990593
    Abstract: A system and method for Quality of Service (QoS) based server cluster power management is disclosed. The method of the present invention includes: grouping activities within a server cluster into predefined sets; assigning a priority level to each set; identifying a server hosting a set of lower-priority activities within the cluster; receiving a power interruption signal; and diverting power reserves of the server to another server in the cluster, in response to the power interruption signal. The system of the present invention includes: servers, hosting a plurality of activity sets each having an associated QoS level; power reserves coupled to the servers; a switch matrix coupled to direct the power reserves between the servers; and a power manager, coupled to the switch matrix, for commanding the switch matrix to divert power from servers hosting low QoS activity sets to servers hosting high-priority activity sets, in response to a power interruption.
    Type: Grant
    Filed: July 31, 2001
    Date of Patent: January 24, 2006
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventor: O Sam Nakagawa
  • Publication number: 20030037150
    Abstract: A system and method for Quality of Service (QoS) based server cluster power management is disclosed. The method of the present invention includes: grouping activities within a server cluster into predefined sets; assigning a priority level to each set; identifying a server hosting a set of lower-priority activities within the cluster; receiving a power interruption signal; and diverting power reserves of the server to another server in the cluster, in response to the power interruption signal. The system of the present invention includes: servers, hosting a plurality of activity sets each having an associated QoS level; power reserves coupled to the servers; a switch matrix coupled to direct the power reserves between the servers; and a power manager, coupled to the switch matrix, for commanding the switch matrix to divert power from servers hosting low QoS activity sets to servers hosting high-priority activity sets, in response to a power interruption.
    Type: Application
    Filed: July 31, 2001
    Publication date: February 20, 2003
    Inventor: O. Sam Nakagawa
  • Patent number: 6018623
    Abstract: A method and system of determining circuit performance-related characteristics, particularly delay and crosstalk, of interconnects includes defining a number of process variables which exhibit Gaussian distributions with respect to geometrical variances. A table of statistically based worst-case values representative of capacitances and resistances associated with different selections of the process variables is generated. In the preferred embodiment, the statistically based worst-case values are 3-sigma values. Also generated is a table of capacitance derivatives with respect to interconnect geometries. When a particular interconnect layout having selected process parameters is designated, the tables of 3-sigma values and derivatives are accessed to generate a resistance-capacitance (RC) net representative of the interconnect layout. The resistance and capacitance are correlated for each RC net and are partially determined by a randomized selection of values for geometries of the interconnect layout.
    Type: Grant
    Filed: October 10, 1997
    Date of Patent: January 25, 2000
    Assignee: Hewlett-Packard Company
    Inventors: Norman H. Chang, Valery Kanevsky, O. Sam Nakagawa, Soo-Young Oh