Patents by Inventor Ryohei Fujimaki

Ryohei Fujimaki 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: 9269118
    Abstract: An abnormality score calculating means calculates abnormality scores which are information indicating abnormality of medical data, based on specificity of the medical data. An abnormality score vector generating means creates at least one or more abnormality score vectors which are information obtained by integrating the abnormality scores. Further, a side effect detecting means which decides a likelihood of a side effect indicated by the abnormality score vector, based on a predetermined rule, and detects an abnormality score vector the likelihood of which is set in advance and which satisfies conditions as information indicating the side effect.
    Type: Grant
    Filed: June 23, 2011
    Date of Patent: February 23, 2016
    Assignee: NEC CORPORATION
    Inventors: Ryohei Fujimaki, Satoshi Morinaga
  • Patent number: 9208436
    Abstract: The model selection device comprises a model optimization unit which optimizes a model for a mixed distribution, wherein related to an information criterion of complete data, with respect to a hidden variable post-event distribution of the complete data, the model optimization unit optimizes an expected information criterion of the complete data for a pair of a model and a parameter of a component which satisfies a predetermined condition.
    Type: Grant
    Filed: March 3, 2011
    Date of Patent: December 8, 2015
    Assignee: NEC CORPORATION
    Inventor: Ryohei Fujimaki
  • Patent number: 9043261
    Abstract: To provide a latent variable model estimation apparatus capable of implementing the model selection at high speed even if the number of model candidates increases exponentially as the latent state number and the kind of the observation probability increase. A variational probability calculating unit 71 calculates a variational probability by maximizing a reference value that is defined as a lower bound of an approximation amount, in which Laplace approximation of a marginalized log likelihood function is performed with respect to an estimator for a complete variable. A model estimation unit 72 estimates an optimum latent variable model by estimating the kind and a parameter of the observation probability with respect to each latent state. A convergence determination unit 73 determines whether a reference value, which is used by the variational probability calculating unit 71 to calculate the variational probability, converges.
    Type: Grant
    Filed: September 13, 2012
    Date of Patent: May 26, 2015
    Assignee: NEC CORPORATION
    Inventors: Ryohei Fujimaki, Satoshi Morinaga
  • Patent number: 9043645
    Abstract: A malfunction analysis apparatus (100) is provided with a malfunction-analysis processor (107), an attribute-extraction processor (108), and an outputter (105). The malfunction-analysis processor (107) obtains a malfunction-contribution degree, which indicates a degree that individual malfunctions (to be called malfunctioning elements, hereafter) contribute to the malfunctioning of the object being analyzed, on the basis of the relative relationship between the data to be analyzed that has, as elements thereof, values generated on the basis of a plurality of indicator values of the object being analyzed, and representative values for the plurality of indicators corresponding to each of the plurality of malfunctions. Then, the malfunctioning elements being generated is specified, on the basis of the obtained malfunction-contribution degree.
    Type: Grant
    Filed: April 26, 2011
    Date of Patent: May 26, 2015
    Assignee: NEC CORPORATION
    Inventors: Ryohei Fujimaki, Hidenori Tsukahara
  • Publication number: 20150120254
    Abstract: A model estimation device includes: a data input unit 101; a state number setting unit; an initialization unit; a latent variable variational probability computation unit which computes a variational probability of a latent variable so as to maximize a lower bound of a model posterior probability limited in degree of freedom; a component optimization unit which estimates an optimal type of each component and a parameter thereof so as to maximize the lower bound of the model posterior probability limited in degree of freedom and separated for each component of a latent variable model; a free parameter selection variable computation unit which computes the free parameter selection variable; an optimality determination unit which determines whether or not to continue the maximization of the lower bound of the model posterior probability; and a result output unit.
    Type: Application
    Filed: October 29, 2013
    Publication date: April 30, 2015
    Applicant: NEC Corporation
    Inventors: Yusuke MURAOKA, Ryohei FUJIMAKI
  • Publication number: 20150120638
    Abstract: A model estimation device includes: a data input unit; a state number setting unit; an initialization unit which sets initial values of a variational probability of a latent variable, a parameter, and the type of each component; a latent variable variational probability computation unit which computes the variational probability of the latent variable so as to maximize a lower bound of a marginal model posterior probability; a component optimization unit which estimates an optimal type of each component and a parameter thereof so as to maximize the lower bound of the marginal model posterior probability separated for each component of the latent variable model; an optimality determination unit which determines whether or not to continue the maximization of the lower bound of the marginal model posterior probability; and a result output unit which outputs a result.
    Type: Application
    Filed: October 29, 2013
    Publication date: April 30, 2015
    Applicant: NEC Corporation
    Inventors: Yusuke MURAOKA, Ryohei FUJIMAKI
  • Publication number: 20150088804
    Abstract: A hierarchical latent structure setting unit 81 sets a hierarchical latent structure that is a structure in which latent variables are represented by a tree structure and components representing probability models are located at nodes of a lowest level of the tree structure. A variational probability computation unit 82 computes a variational probability of a path latent variable that is a latent variable included in a path linking a root node to a target node in the hierarchical latent structure. A component optimization unit 83 optimizes each of the components for the computed variational probability. A gating function optimization unit 84 optimizes a gating function model that is a model for determining a branch direction according to the multivariate data in a node of the hierarchical latent structure, on the basis of the variational probability of the latent variable in the node.
    Type: Application
    Filed: December 8, 2014
    Publication date: March 26, 2015
    Inventors: Riki ETO, Ryohei FUJIMAKI, Satoshi MORINAGA
  • Publication number: 20150088789
    Abstract: A hierarchical latent structure setting unit 81 sets a hierarchical latent structure that is a structure in which latent variables are represented by a tree structure and components representing probability models are located at nodes of a lowest level of the tree structure. A variational probability computation unit 82 computes a variational probability of a path latent variable that is a latent variable included in a path linking a root node to a target node in the hierarchical latent structure. A component optimization unit 83 optimizes each of the components for the computed variational probability. A gating function optimization unit 84 optimizes a gating function model that is a model for determining a branch direction according to the multivariate data in a node of the hierarchical latent structure, based on the variational probability of the latent variable in the node.
    Type: Application
    Filed: September 20, 2013
    Publication date: March 26, 2015
    Applicant: NEC Corporation
    Inventors: Yosuke MOTOHASHI, Satoshi MORINAGA, Ryohei FUJIMAKI, Riki ETO
  • Publication number: 20150074019
    Abstract: A memory that stores health checkup data of a person and a label value representing whether or not the person fell under a predetermined health guidance criterion in the subsequent period, and a processor connected with the memory are provided. The processor learns a discriminant model with use of the health checkup data of each person and the label value. The discriminant model, in which health checkup items of the health checkup data are used as explanatory variables, is represented as a polynomial including the explanatory variables and coefficients of the respective explanatory variables, and is used for discriminating whether or not the person falls under the health guidance criterion in the subsequent period. The processor generates, as a selection condition, combinations of the health checkup items as the explanatory variables and values of the coefficients in the discriminant model after learning.
    Type: Application
    Filed: April 3, 2013
    Publication date: March 12, 2015
    Inventors: Yuki Kosaka, Masataka Andou, Ryohei Fujimaki
  • Patent number: 8943511
    Abstract: A parallel allocation calculating unit calculates a parallel allocation candidate which is an element candidate in target data allocated per processing performed in parallel. A parallel calculation amount estimation processing unit estimates the calculation amount required for parallel processing when a parallel allocation candidate is allocated, based on a nonzero element count in the target data. An optimality decision processing unit decides whether or not the parallel allocation candidate is optimal based on the calculated calculation amount, and allocates the optimal element per processing performed in parallel.
    Type: Grant
    Filed: October 17, 2012
    Date of Patent: January 27, 2015
    Assignee: NEC Corporation
    Inventors: Ryohei Fujimaki, Kouhei Hayashi
  • Patent number: 8909582
    Abstract: A hierarchical latent structure setting unit 81 sets a hierarchical latent structure that is a structure in which latent variables are represented by a tree structure and components representing probability models are located at nodes of a lowest level of the tree structure. A variational probability computation unit 82 computes a variational probability of a path latent variable that is a latent variable included in a path linking a root node to a target node in the hierarchical latent structure. A component optimization unit 83 optimizes each of the components for the computed variational probability. A gating function optimization unit 84 optimizes a gating function model that is a model for determining a branch direction according to the multivariate data in a node of the hierarchical latent structure, on the basis of the variational probability of the latent variable in the node.
    Type: Grant
    Filed: February 4, 2013
    Date of Patent: December 9, 2014
    Assignee: NEC Corporation
    Inventors: Riki Eto, Ryohei Fujimaki, Satoshi Morinaga
  • Publication number: 20140344183
    Abstract: An approximate computation unit computes an approximate of a determinant of a Hessian matrix relating to observed data represented as a matrix. A variational probability computation unit computes a variational probability of a latent variable using the approximate of the determinant. A latent state removal unit removes a latent state based on a variational distribution. A parameter optimization unit optimizes a parameter for a criterion value that is defined as a lower bound of an approximate obtained by Laplace-approximating a marginal log-likelihood function with respect to an estimator for a complete variable, and computes the criterion value. A convergence determination unit determines whether or not the criterion value has converged.
    Type: Application
    Filed: May 20, 2013
    Publication date: November 20, 2014
    Applicant: NEC CORPORATION
    Inventors: Ryohei FUJIMAKI, Kouhei HAYASHI
  • Publication number: 20140343903
    Abstract: An approximate computation unit computes an approximate of a determinant of a Hessian matrix relating to a parameter of an observation model represented as a linear combination of parameters determined by each layer 1 latent variable of factorial hidden Markov models. A variational probability computation unit computes a variational probability of a latent variable using the approximate of the determinant. A latent state removal unit removes a latent state based on a variational distribution. A parameter optimization unit optimizes the parameter for a criterion value that is defined as a lower bound of an approximate obtained by Laplace-approximating a marginal log-likelihood function with respect to an estimator for a complete variable, and computes the criterion value. A convergence determination unit determines whether or not the criterion value has converged.
    Type: Application
    Filed: May 20, 2013
    Publication date: November 20, 2014
    Applicant: NEC CORPORATION
    Inventors: Ryohei FUJIMAKI, Shaohua LI
  • Patent number: 8832006
    Abstract: To provide a discriminant model learning device capable of efficiently learning a discriminant model on which domain knowledge indicating user's knowledge or analysis intention for a model is reflected while keeping fitting to data. A query candidate storage means 81 stores candidates of a query as a model to be given with domain knowledge indicating a user's intention. A regularization function generation means 82 generates a regularization function indicating compatibility with domain knowledge based on the domain knowledge to be given to the query candidates. A model learning means 83 learns a discriminant model by optimizing a function defined by a loss function and the regularization function predefined per discriminant model.
    Type: Grant
    Filed: May 31, 2012
    Date of Patent: September 9, 2014
    Assignee: NEC Corporation
    Inventors: Satoshi Morinaga, Ryohei Fujimaki, Yoshinobu Kawahara
  • Publication number: 20140236869
    Abstract: An optimality degree computation unit computes an optimality degree in the case where a first variable included in a variable set is a candidate for an addition variable, using an objective function. An addition threshold computation unit computes an addition threshold based on the computed optimality degree, the addition threshold being a threshold of the optimality degree and indicating a criterion for determining whether or not the first variable is to be set as the candidate for the addition variable. An objective function value computation unit computes an objective function value which is a difference between a value of the objective function computed using variables to be optimized and a value of the objective function computed using the variables to be optimized from which a second variable included in a nonzero variable set is excluded.
    Type: Application
    Filed: January 29, 2014
    Publication date: August 21, 2014
    Applicant: NEC CORPORATION
    Inventors: Ryohei FUJIMAKI, Satoshi MORINAGA, Ji LIU, Yoshinobu KAWAHARA
  • Publication number: 20140236871
    Abstract: A gradient computation unit computes a gradient of an objective function in a variable to be optimized. An added variable selection unit adds a variable corresponding to a largest absolute value of the computed gradient from among variables included in a variable set, to a nonzero variable set. A variable optimization unit optimizes a value of the variable to be optimized, for each variable included in the nonzero variable set. A deleted variable selection unit deletes a variable that, when deleted, causes a smallest increase of the objective function from among variables included in the nonzero variable set, from the nonzero variable set. An objective function evaluation unit computes a value of the objective function for the variable to be optimized.
    Type: Application
    Filed: January 27, 2014
    Publication date: August 21, 2014
    Applicant: NEC CORPORATION
    Inventors: Ryohei FUJIMAKI, Ji LIU
  • Publication number: 20140222741
    Abstract: A hierarchical latent structure setting unit 81 sets a hierarchical latent structure that is a structure in which latent variables are represented by a tree structure and components representing probability models are located at nodes of a lowest level of the tree structure. A variational probability computation unit 82 computes a variational probability of a path latent variable that is a latent variable included in a path linking a root node to a target node in the hierarchical latent structure. A component optimization unit 83 optimizes each of the components for the computed variational probability. A gating function optimization unit 84 optimizes a gating function model that is a model for determining a branch direction according to the multivariate data in a node of the hierarchical latent structure, on the basis of the variational probability of the latent variable in the node.
    Type: Application
    Filed: February 4, 2013
    Publication date: August 7, 2014
    Applicant: NEC CORPORATION
    Inventors: Riki ETO, Ryohei FUJIMAKI, Satoshi MORINAGA
  • Publication number: 20140214747
    Abstract: With respect to the model selection issue of a mixture model, the present invention performs high-speed model selection under an appropriate standard regarding the number of model candidates which exponentially increases as the number and the types to be mixed increase.
    Type: Application
    Filed: April 2, 2014
    Publication date: July 31, 2014
    Applicant: NEC CORPORATION
    Inventors: Ryohei FUJIMAKI, Satoshi MORINAGA
  • Patent number: 8731881
    Abstract: With respect to the model selection issue of a mixture model, the present invention performs high-speed model selection under an appropriate standard regarding the number of model candidates which exponentially increases as the number and the types to be mixed increase.
    Type: Grant
    Filed: March 16, 2012
    Date of Patent: May 20, 2014
    Assignee: NEC Corporation
    Inventors: Ryohei Fujimaki, Satoshi Morinaga
  • Publication number: 20140114890
    Abstract: In order to learn an appropriate probability model in a probability model learning problem where a first issue and a second issue manifest concurrently by solving the two at the same time, provided is a probability model estimation device for obtaining a probability model estimation result from first to T-th (T?2) training data and test data.
    Type: Application
    Filed: May 24, 2012
    Publication date: April 24, 2014
    Inventors: Ryohei Fujimaki, Satoshi Morinaga, Masashi Sugiyama