Patents by Inventor Spyridon Papadimitriou

Spyridon Papadimitriou 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: 8818918
    Abstract: Computer-implemented methods, systems, and articles of manufacture for determining the importance of a data item. A method includes: (a) receiving a node graph; (b) approximating a number of neighbor nodes of a node; and (c) calculating a average shortest path length of the node to the remaining nodes using the approximation step, where this calculation demonstrates the importance of a data item represented by the node. Another method includes: (a) receiving a node graph; (b) building a decomposed line graph of the node graph; (c) calculating stationary probabilities of incident edges of a node graph node in the decomposed line graph, and (d) calculating a summation of the stationary probabilities of the incident edges associated with the node, where the summation demonstrates the importance of a data item represented by the node. Both methods have at least one step carried out using a computer device.
    Type: Grant
    Filed: April 28, 2011
    Date of Patent: August 26, 2014
    Assignee: International Business Machines Corporation
    Inventors: Ching-Yung Lin, Hanghang Tong, Jimeng Sun, Spyridon Papadimitriou, U Kang
  • Publication number: 20120278261
    Abstract: Computer-implemented methods, systems, and articles of manufacture for determining the importance of a data item. A method includes: (a) receiving a node graph; (b) approximating a number of neighbor nodes of a node; and (c) calculating a average shortest path length of the node to the remaining nodes using the approximation step, where this calculation demonstrates the importance of a data item represented by the node. Another method includes: (a) receiving a node graph; (b) building a decomposed line graph of the node graph; (c) calculating stationary probabilities of incident edges of a node graph node in the decomposed line graph, and (d) calculating a summation of the stationary probabilities of the incident edges associated with the node, where the summation demonstrates the importance of a data item represented by the node. Both methods have at least one step carried out using a computer device.
    Type: Application
    Filed: April 28, 2011
    Publication date: November 1, 2012
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Ching-Yung Lin, Hanghang Tong, Jimeng Sun, Spyridon Papadimitriou, U Kang
  • Patent number: 8086655
    Abstract: Techniques for perturbing an evolving data stream are provided. The evolving data stream is received. An online linear transformation is applied to received values of the evolving data stream generating a plurality of transform coefficients. A plurality of significant transform coefficients are selected from the plurality of transform coefficients. Noise is embedded into each of the plurality of significant transform coefficients, thereby perturbing the evolving data stream. A total noise variance does not exceed a defined noise variance threshold.
    Type: Grant
    Filed: September 14, 2007
    Date of Patent: December 27, 2011
    Assignee: International Business Machines Corporation
    Inventors: Philip Shi-Lung Yu, Spyridon Papadimitriou
  • Patent number: 7945570
    Abstract: A computer-implemented method, system, and a computer readable article of manufacture identify local patterns in at least one time series data stream. A data stream is received that comprises at least one set of time series data. The at least one set of time series data is formed into a set of multiple ordered levels of time series data. Multiple ordered levels of hierarchical approximation functions are generated directly from the multiple ordered levels of time series data. A set of approximating functions are created for each level. A current window with a current window length is selected from a set of varying window lengths. The set of approximating functions created at one level in the multiple ordered levels is passed to a subsequent level as a set of time series data. The multiple ordered levels of hierarchical approximation functions are stored into memory after being generated.
    Type: Grant
    Filed: August 31, 2009
    Date of Patent: May 17, 2011
    Assignee: International Business Machines Corporation
    Inventors: Spyridon Papadimitriou, Philip S. Yu
  • Publication number: 20110055379
    Abstract: System and method for modeling a content-based network. The method includes finding single mode clusters from among network (sender and recipient) and content dimensions represented as a tensor data structure. The method allows for derivation of useful cross-mode clusters (interpretable patterns) that reveal key relationships among user communities and keyword concepts for presentation to users in a meaningful and intuitive way. Additionally, the derivation of useful cross-mode clusters is facilitated by constructing a reduced low-dimensional representation of the content-based network. Moreover, the invention may be enhanced for modeling and analyzing the time evolution of social communication networks and the content related to such networks. To this end, a set of non-overlapping or possibly overlapping time-based windows is constructed and the analysis performed at each successive time interval.
    Type: Application
    Filed: September 2, 2009
    Publication date: March 3, 2011
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Ching-Yung Lin, Spyridon Papadimitriou, Jimeng Sun, Kun-Lung Wu
  • Patent number: 7853545
    Abstract: Disclosed is a method, information processing system, and computer readable medium for preserving privacy of nonstationary data streams. The method includes receiving at least one nonstationary data stream with time dependent data. Calculating, for a given instant of sub-space of time, A set of first-moment statistical values is calculated, for a given instant of sub-space of time, for the data. The first moment statistical values include a principal component for the sub-space of time. The data is perturbed with noise along the principal component in proportion to the first-moment of statistical values so that at least part of a set of second-moment statistical values for the data is perturbed by the noise only within a predetermined variance.
    Type: Grant
    Filed: February 26, 2007
    Date of Patent: December 14, 2010
    Assignee: International Business Machines Corporation
    Inventors: Yuan-Chi Chang, Feifei Li, Spyridon Papadimitriou, George A. Mihaila, Ioana Stanoi, Jimeng Sun, Philip S. Yu
  • Patent number: 7840516
    Abstract: A method, information processing system, and computer readable medium are provided for preserving privacy of one-dimensional nonstationary data streams. The method includes receiving a one-dimensional nonstationary data stream. A set of first-moment statistical values are calculated, for a given instant of sub-space of time, for the data. The first moment statistical values include a principal component for the sub-space of time. The data is perturbed with noise along the principal component in proportion to the first-moment of statistical values so that at least part of a set of second-moment statistical values for the data is perturbed by the noise only within a predetermined variance.
    Type: Grant
    Filed: February 26, 2007
    Date of Patent: November 23, 2010
    Assignee: International Business Machines Corporation
    Inventors: Yuan-Chi Chang, Feifei Li, Spyridon Papadimitriou, George A. Mihaila, Ioana Stanoi, Jimeng Sun, Philip S. Yu
  • Patent number: 7730364
    Abstract: A system and method for using continuous failure predictions for proactive failure management in distributed cluster systems includes a sampling subsystem configured to continuously monitor and collect operation states of different system components. An analysis subsystem is configured to build classification models to perform on-line failure predictions. A failure prevention subsystem is configured to take preventive actions on failing components based on failure warnings generated by the analysis subsystem.
    Type: Grant
    Filed: April 5, 2007
    Date of Patent: June 1, 2010
    Assignee: International Business Machines Corporation
    Inventors: Shu-Ping Chang, Xiaohui Gu, Spyridon Papadimitriou, Philip Shi-lung Yu
  • Publication number: 20100063974
    Abstract: A computer-implemented method, system, and a computer readable article of manufacture identify local patterns in at least one time series data stream. A data stream is received that comprises at least one set of time series data. The at least one set of time series data is formed into a set of multiple ordered levels of time series data. Multiple ordered levels of hierarchical approximation functions are generated directly from the multiple ordered levels of time series data. A set of approximating functions are created for each level. A current window with a current window length is selected from a set of varying window lengths. The set of approximating functions created at one level in the multiple ordered levels is passed to a subsequent level as a set of time series data. The multiple ordered levels of hierarchical approximation functions are stored into memory after being generated.
    Type: Application
    Filed: August 31, 2009
    Publication date: March 11, 2010
    Applicant: International Business Machines
    Inventors: SPYRIDON PAPADIMITRIOU, Philip S. Yu
  • Publication number: 20090077148
    Abstract: Techniques for perturbing an evolving data stream are provided. The evolving data stream is received. An online linear transformation is applied to received values of the evolving data stream generating a plurality of transform coefficients. A plurality of significant transform coefficients are selected from the plurality of transform coefficients. Noise is embedded into each of the plurality of significant transform coefficients, thereby perturbing the evolving data stream. A total noise variance does not exceed a defined noise variance threshold.
    Type: Application
    Filed: September 14, 2007
    Publication date: March 19, 2009
    Inventors: Philip Shi-Lung Yu, Spyridon Papadimitriou
  • Patent number: 7505876
    Abstract: In an exemplary embodiment, some of the main aspects of the present invention are the following: (i) Data model: We introduce tensor streams to deal with large collections of multi-aspect streams; and (ii) Algorithmic framework: We propose window-based tensor analysis (WTA) to effectively extract core patterns from tensor streams. The tensor representation is related to data cube in On-Line Analytical Processing (OLAP). However, our present invention focuses on constructing simple summaries for each window, rather than merely organizing the data to produce simple aggregates along each aspect or combination of aspects.
    Type: Grant
    Filed: January 7, 2007
    Date of Patent: March 17, 2009
    Assignee: International Business Machines Corporation
    Inventors: Spyridon Papadimitriou, Jimeng Sun, Philip S. Yu
  • Patent number: 7483934
    Abstract: An exemplary method for computing correlation anomaly scores, including, defining a first similarity matrix for a target run of data, the target run of data includes an N number of sensors, defining a second similarity matrix for a reference run of data, the target run of data includes the N number of sensors, developing a k-neighborhood graph Ni of the i-th node for the target run of data, wherein the k-neighborhood graph of the i-th node is defined as a graph comprising the i-th node and its k-nearest neighbors (NN), developing a k-neighborhood graph Ni of the i-th node for the reference run of data, defining a probability distribution p(j|i), wherein p(j|i) is the probability that the j-th node becomes one of the k-NN of the i-th node, coupling the probability between the i-th node and the neighbors of the i-th node, determining an anomaly score of the i-th node, and determining whether the target run of data has changed from the reference run of data responsive to determining the anomaly score of the i-th
    Type: Grant
    Filed: December 18, 2007
    Date of Patent: January 27, 2009
    Assignee: International Busniess Machines Corporation
    Inventors: Tsuyoshi Ide, Spyridon Papadimitriou
  • Publication number: 20080250265
    Abstract: A system and method for using continuous failure predictions for proactive failure management in distributed cluster systems includes a sampling subsystem configured to continuously monitor and collect operation states of different system components. An analysis subsystem is configured to build classification models to perform on-line failure predictions. A failure prevention subsystem is configured to take preventive actions on failing components based on failure warnings generated by the analysis subsystem.
    Type: Application
    Filed: April 5, 2007
    Publication date: October 9, 2008
    Inventors: SHU-PING CHANG, Xiaohui Gu, Spyridon Papadimitriou, Philip Shi-lung Yu
  • Publication number: 20080209568
    Abstract: Disclosed is a method, information processing system, and computer readable medium for preserving privacy of nonstationary data streams. The method includes receiving at least one nonstationary data stream with time dependent data. Calculating, for a given instant of sub-space of time, A set of first-moment statistical values is calculated, for a given instant of sub-space of time, for the data. The first moment statistical values include a principal component for the sub-space of time. The data is perturbed with noise along the principal component in proportion to the first-moment of statistical values so that at least part of a set of second-moment statistical values for the data is perturbed by the noise only within a predetermined variance.
    Type: Application
    Filed: February 26, 2007
    Publication date: August 28, 2008
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Yuan-Chi Chang, Feifei Li, Spyridon Papadimitriou, George A. Mihaila, Ioana Stanoi, Jimeng Sun, Philip S. Yu
  • Publication number: 20080205641
    Abstract: A method, information processing system, and computer readable medium are provided for preserving privacy of one-dimensional nonstationary data streams. The method includes receiving a one-dimensional nonstationary data stream. A set of first-moment statistical values are calculated, for a given instant of sub-space of time, for the data. The first moment statistical values include a principal component for the sub-space of time. The data is perturbed with noise along the principal component in proportion to the first-moment of statistical values so that at least part of a set of second-moment statistical values for the data is perturbed by the noise only within a predetermined variance.
    Type: Application
    Filed: February 26, 2007
    Publication date: August 28, 2008
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Yuan-Chi Chang, Feifei Li, Spyridon Papadimitriou, George A. Mihaila, Ioana Stanoi, Jimeng Sun, Philip S. Yu
  • Publication number: 20080168375
    Abstract: In an exemplary embodiment, some of the main aspects of the present invention are the following: (i) Data model: We introduce tensor streams to deal with large collections of multi-aspect streams; and (ii) Algorithmic framework: We propose window-based tensor analysis (WTA) to effectively extract core patterns from tensor streams. The tensor representation is related to data cube in On-Line Analytical Processing (OLAP). However, our present invention focuses on constructing simple summaries for each window, rather than merely organizing the data to produce simple aggregates along each aspect or combination of aspects.
    Type: Application
    Filed: January 7, 2007
    Publication date: July 10, 2008
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Spyridon Papadimitriou, Jimeng Sun, Philip S. Yu
  • Publication number: 20080071843
    Abstract: Systems and methods for reordering dimensions of a multiple-dimensional dataset includes ordering dimensions of multi-dimensional dataset such that original D dimensions of the data are reordered to obtain a smooth sequence representation which includes placement of the D dimensions with similar behavior at adjacent positions in an ordered sequence representation. The ordered sequence representation is segmented into groups of K<D dimensions for placement in a K-dimensional indexing structure.
    Type: Application
    Filed: September 14, 2006
    Publication date: March 20, 2008
    Inventors: Spyridon Papadimitriou, Zografoula Vagena, Michail Vlachos, Philip Shi-lung Yu
  • Publication number: 20070294247
    Abstract: A method, system, and computer readable medium for identifying local patterns in at least one time series data stream are disclosed. The method comprises generating multiple ordered levels of hierarchal approximation functions. The multiple ordered levels are generated directly from at least one given time series data stream including at least one set of time series data. The hierarchical approximation functions for each level of the multiple levels is based upon creating a set of approximating functions. The hierarchical approximation functions are also based upon selecting a current window with a current window length from a set of varying window lengths. The current window is selected for a current level of the multiple levels.
    Type: Application
    Filed: June 20, 2006
    Publication date: December 20, 2007
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Spyridon Papadimitriou, Philip S. Yu