Updated on 2024/03/05

写真a

 
KUBO Masahiro
 
Name of department
Faculty of Systems Engineering, Fundamental Subjects
Job title
Professor
Mail Address
E-mail address
Homepage
External link

Education

  • 1985
    -
    1988

    東京大学大学院   理学系研究科博士課程   相関理化学専攻  

  • 1983
    -
    1985

    千葉大学大学院   理学研究科修士課程   数学専攻  

  • 1980
    -
    1983

    The University of Tokyo   College of Arts and Sciences   Department of Basic Science  

  • 1978
    -
    1980

    The University of Tokyo   理科Ⅱ類  

Degree

  • (BLANK)

Academic & Professional Experience

  • 2015.04
    -
    Now

    Wakayama University   Faculty of Systems Engineering   教授

  • 2006.04
    -
    2015.03

    Nagoya Institute of Technology   Graduate School of Engineering   Professor

  • 1990.04
    -
    2006.03

    Saga University   Faculty of Science and Engineering   助教授

  • 1988.04
    -
    1990.03

    Saga University   Faculty of Science and Engineering   助手

Research Areas

  • Natural sciences / Mathematical analysis

Classes (including Experimental Classes, Seminars, Graduation Thesis Guidance, Graduation Research, and Topical Research)

  • 2022   Linear Algebra 2   Specialized Subjects

  • 2022   Linear Algebra 2   Specialized Subjects

  • 2022   Linear Algebra 2   Specialized Subjects

  • 2022   Linear Algebra 1   Specialized Subjects

  • 2022   Linear Algebra 1   Specialized Subjects

  • 2022   Linear Algebra 1   Specialized Subjects

  • 2022   Linear Algebra 1   Specialized Subjects

  • 2022   Applied Analysis   Specialized Subjects

  • 2022   Introductory Seminar in Systems Engineering   Specialized Subjects

  • 2021   Linear Algebra 2   Specialized Subjects

  • 2021   Linear Algebra 2   Specialized Subjects

  • 2021   Linear Algebra 2   Specialized Subjects

  • 2021   Linear Algebra 2   Specialized Subjects

  • 2021   Linear Algebra 1   Specialized Subjects

  • 2021   Linear Algebra 1   Specialized Subjects

  • 2021   Linear Algebra 1   Specialized Subjects

  • 2021   Linear Algebra 1   Specialized Subjects

  • 2021   Linear Algebra 1   Specialized Subjects

  • 2021   Applied Analysis   Specialized Subjects

  • 2020   Introductory Seminar in Systems Engineering   Specialized Subjects

  • 2020   Linear Algebra 2   Specialized Subjects

  • 2020   Linear Algebra 2   Specialized Subjects

  • 2020   Linear Algebra 1   Specialized Subjects

  • 2020   Applied Analysis   Specialized Subjects

  • 2019   Linear Algebra 2   Specialized Subjects

  • 2019   Linear Algebra 2   Specialized Subjects

  • 2019   Linear Algebra 1   Specialized Subjects

  • 2019   Applied Analysis   Specialized Subjects

  • 2018   Linear Algebra 2   Specialized Subjects

  • 2018   Linear Algebra 1   Specialized Subjects

  • 2018   Applied Analysis   Specialized Subjects

  • 2017   Introductory Seminar in Systems Engineering   Specialized Subjects

  • 2017   Linear Algebra 2   Specialized Subjects

  • 2017   Linear Algebra 2   Specialized Subjects

  • 2017   Linear Algebra 1   Specialized Subjects

  • 2017   Applied Analysis   Specialized Subjects

  • 2016   Linear Algebra 2   Specialized Subjects

  • 2016   Linear Algebra 2   Specialized Subjects

  • 2016   Linear Algebra 1   Specialized Subjects

  • 2016   Applied Analysis   Specialized Subjects

  • 2015   Linear Algebra 1   Specialized Subjects

  • 2015   Applied Analysis   Specialized Subjects

  • 2015   Linear Algebra 2   Specialized Subjects

▼display all

Classes

  • 2022   Systems Engineering Global Seminar Ⅱ   Doctoral Course

  • 2022   Systems Engineering Global Seminar Ⅰ   Doctoral Course

  • 2022   Systems Engineering Advanced Research   Doctoral Course

  • 2022   Systems Engineering Advanced Seminar Ⅱ   Doctoral Course

  • 2022   Systems Engineering Advanced Seminar Ⅰ   Doctoral Course

  • 2022   Systems Engineering Project SeminarⅡB   Master's Course

  • 2022   Systems Engineering Project SeminarⅡA   Master's Course

  • 2022   Systems Engineering Project SeminarⅠB   Master's Course

  • 2022   Systems Engineering Project SeminarⅠA   Master's Course

  • 2022   Systems Engineering SeminarⅡB   Master's Course

  • 2022   Systems Engineering SeminarⅡA   Master's Course

  • 2022   Systems Engineering SeminarⅠB   Master's Course

  • 2022   Systems Engineering SeminarⅠA   Master's Course

  • 2021   Systems Engineering Global Seminar Ⅱ   Doctoral Course

  • 2021   Systems Engineering Global Seminar Ⅰ   Doctoral Course

  • 2021   Systems Engineering Advanced Research   Doctoral Course

  • 2021   Systems Engineering Advanced Seminar Ⅱ   Doctoral Course

  • 2021   Systems Engineering Advanced Seminar Ⅰ   Doctoral Course

  • 2021   Systems Engineering Project SeminarⅡB   Master's Course

  • 2021   Systems Engineering Project SeminarⅡA   Master's Course

  • 2021   Systems Engineering Project SeminarⅠB   Master's Course

  • 2021   Systems Engineering Project SeminarⅠA   Master's Course

  • 2021   Systems Engineering SeminarⅡB   Master's Course

  • 2021   Systems Engineering SeminarⅡA   Master's Course

  • 2021   Systems Engineering SeminarⅠB   Master's Course

  • 2021   Systems Engineering SeminarⅠA   Master's Course

  • 2020   Systems Engineering Global Seminar Ⅱ   Doctoral Course

  • 2020   Systems Engineering Global Seminar Ⅰ   Doctoral Course

  • 2020   Systems Engineering Advanced Research   Doctoral Course

  • 2020   Systems Engineering Advanced Seminar Ⅱ   Doctoral Course

  • 2020   Systems Engineering Advanced Seminar Ⅰ   Doctoral Course

  • 2020   Systems Engineering Project SeminarⅡB   Master's Course

  • 2020   Systems Engineering Project SeminarⅡA   Master's Course

  • 2020   Systems Engineering Project SeminarⅠB   Master's Course

  • 2020   Systems Engineering Project SeminarⅠA   Master's Course

  • 2020   Systems Engineering SeminarⅡB   Master's Course

  • 2020   Systems Engineering SeminarⅡA   Master's Course

  • 2020   Systems Engineering SeminarⅠB   Master's Course

  • 2020   Systems Engineering SeminarⅠA   Master's Course

  • 2019   Systems Engineering Advanced Research   Doctoral Course

  • 2019   Systems Engineering Advanced Research   Doctoral Course

  • 2019   Systems Engineering SeminarⅡB   Master's Course

  • 2019   Systems Engineering SeminarⅡA   Master's Course

  • 2019   Systems Engineering SeminarⅠB   Master's Course

  • 2019   Systems Engineering SeminarⅠA   Master's Course

  • 2019   Systems Engineering Global Seminar Ⅰ   Doctoral Course

  • 2019   Systems Engineering Global Seminar Ⅰ   Doctoral Course

  • 2019   Systems Engineering Project SeminarⅡB   Master's Course

  • 2019   Systems Engineering Project SeminarⅡA   Master's Course

  • 2019   Systems Engineering Project SeminarⅡA   Master's Course

  • 2019   Systems Engineering Project SeminarⅠB   Master's Course

  • 2019   Systems Engineering Project SeminarⅠA   Master's Course

  • 2018   Systems Engineering Global Seminar Ⅱ   Doctoral Course

  • 2018   Systems Engineering Global Seminar Ⅱ   Doctoral Course

  • 2018   Systems Engineering Advanced Research   Doctoral Course

  • 2018   Systems Engineering Advanced Research   Doctoral Course

  • 2018   Systems Engineering Project SeminarⅡB   Master's Course

  • 2018   Systems Engineering Project SeminarⅡA   Master's Course

  • 2018   Systems Engineering Project SeminarⅠB   Master's Course

  • 2018   Systems Engineering Project SeminarⅠA   Master's Course

  • 2018   Systems Engineering SeminarⅡB   Master's Course

  • 2018   Systems Engineering SeminarⅡA   Master's Course

  • 2018   Systems Engineering SeminarⅠB   Master's Course

  • 2018   Systems Engineering SeminarⅠA   Master's Course

  • 2017   Systems Engineering Global Seminar Ⅰ   Doctoral Course

  • 2017   Systems Engineering Advanced Research   Doctoral Course

  • 2017   Systems Engineering Advanced Seminar Ⅱ   Doctoral Course

  • 2017   Systems Engineering Project SeminarⅡA   Master's Course

  • 2017   Systems Engineering Project SeminarⅠA   Master's Course

  • 2017   Systems Engineering SeminarⅡB   Master's Course

  • 2017   Systems Engineering SeminarⅡA   Master's Course

  • 2017   Systems Engineering SeminarⅠB   Master's Course

  • 2017   Systems Engineering SeminarⅠA   Master's Course

  • 2016   Systems Engineering Global Seminar Ⅱ   Doctoral Course

  • 2016   Systems Engineering Global Seminar Ⅱ   Doctoral Course

  • 2016   Systems Engineering Advanced Research   Doctoral Course

  • 2016   Systems Engineering Advanced Research   Doctoral Course

  • 2016   Systems Engineering Advanced Seminar Ⅱ   Doctoral Course

  • 2016   Systems Engineering Advanced Seminar Ⅱ   Doctoral Course

  • 2016   Systems Engineering Project SeminarⅡB   Master's Course

  • 2016   Systems Engineering Project SeminarⅡA   Master's Course

  • 2016   Systems Engineering Project SeminarⅠB   Master's Course

  • 2016   Systems Engineering Project SeminarⅠA   Master's Course

  • 2016   Systems Engineering SeminarⅡB   Master's Course

  • 2016   Systems Engineering SeminarⅡA   Master's Course

  • 2016   Systems Engineering SeminarⅠB   Master's Course

  • 2016   Systems Engineering SeminarⅠA   Master's Course

  • 2016   Information and Communications Technology for Civilized Society   Master's Course

  • 2015   Systems Engineering Advanced Seminar Ⅱ  

  • 2015   Systems Engineering Advanced Seminar Ⅰ  

  • 2015   Systems Engineering Advanced Research  

  • 2015   Systems Engineering SeminarⅡA  

  • 2015   Systems Engineering SeminarⅠA  

  • 2015   Systems Engineering Project SeminarⅡA  

  • 2015   Systems Engineering Project SeminarⅠA  

  • 2015   Systems Engineering Global Seminar Ⅰ  

  • 2015   Systems Engineering Advanced Seminar Ⅱ  

  • 2015   Systems Engineering Advanced Seminar Ⅰ  

  • 2015   Systems Engineering Advanced Research  

  • 2015   Systems Engineering SeminarⅡB  

  • 2015   Systems Engineering SeminarⅠB  

  • 2015   Systems Engineering Project SeminarⅡB  

  • 2015   Systems Engineering Project SeminarⅠB  

  • 2015   Systems Engineering Global Seminar Ⅰ  

▼display all

Satellite Courses

  • 2016   Information and Communications Technology for Civilized Society  

Research Interests

  • nonlinear analysis

  • 非線形解析

Published Papers

  • Elliptic-Parabolic Quasi-Variational Evolution Equations

    Masahiro Kubo, Noriaki Yamazaki

    FUNKCIALAJ EKVACIOJ   67 ( 1 ) 1 - 27   2024.04  [Refereed]

  • Periodic solutions to a class of quasi-variational evolution equations

    Masahiro Kubo, Noriaki Yamazaki

    Journal of Differential Equations   384   165 - 192   2024.03  [Refereed]

  • Time-dependent subdifferential evolution equations and quasi-variational evolution equations

    Masahiro Kubo

    2 0 2 2 年度日本数学会年会 総合講演・企画特別講演アブストラクト     51 - 66   2022.03  [Invited]

  • Global strong solutions to abstract quasi-variational evolution equations

    Masahiro Kubo, Noriaki Yamazaki

    Journal of Differential Equations ( Academic Press Inc. )  265 ( 9 ) 4158 - 4180   2018  [Refereed]

    　View Summary

    We prove the existence of a time-global strong solution of a class of abstract quasi-variational evolution equations and apply the abstract result to concrete parabolic variational and quasi-variational inequalities.

    DOI

  • Quasi-variational analysis

    Masahiro Kubo

    Sugaku Expositions   30 ( 1 ) 17 - 34   2017.06  [Refereed]  [Invited]

  • Quasi-subdifferential operator approach to elliptic variational and quasi-variational inequalities

    M. Kubo, Y. Murase

    MATHEMATICAL METHODS IN THE APPLIED SCIENCES ( WILEY-BLACKWELL )  39 ( 18 ) 5626 - 5635   2016.12  [Refereed]

    　View Summary

    We prove an existence theorem for an abstract operator equation associated with a quasi-subdifferential operator and then apply it to concrete elliptic variational and quasi-variational inequalities. Copyright (c) 2016 John Wiley & Sons, Ltd.

    DOI

  • Quasi-variational principles and quasi-subdifferential operators

    Msashiro Kubo

    GAKUTO International Series. Mathematical Sciences and Applications   36   165 - 174   2013.11  [Refereed]

  • Quasi-subdifferential operators and evolution equations

    M. Kubo

    Discrete and Continuous Dynamical Systems supplement     447 - 456   2013.11  [Refereed]

  • 準変分解析

    久保 雅弘

    数学   65 ( 4 ) 385 - 401   2013.10  [Refereed]  [Invited]

  • The Cahn-Hilliard equation with time-dependent constraint

    Masahiro Kubo

    NONLINEAR ANALYSIS-THEORY METHODS & APPLICATIONS ( PERGAMON-ELSEVIER SCIENCE LTD )  75 ( 14 ) 5672 - 5685   2012.09  [Refereed]

    　View Summary

    We propose an abstract variational inequality formulation of the Cahn-Hilliard equation with a time-dependent constraint. We introduce notions of strong and weak solutions, and prove that a strong solution, if it exists, is a weak solution, and that the existence of a unique weak solution holds under an appropriate time-dependence condition on the constraint. We also show that the weak solution is a strong solution under appropriate assumptions on the data. Our abstract results can be applied to various concrete problems. (C) 2012 Elsevier Ltd. All rights reserved.

    DOI

  • Variational inequalities for a system of elliptic-parabolic equations

    M. Kubo, K. Shirakawa, N. Yamazaki

    JOURNAL OF MATHEMATICAL ANALYSIS AND APPLICATIONS ( ACADEMIC PRESS INC ELSEVIER SCIENCE )  387 ( 2 ) 490 - 511   2012.03  [Refereed]

    　View Summary

    We create a general framework for mathematical study of variational inequalities for a system of elliptic-parabolic equations. In this paper, we establish a solvability theorem concerning the existence of solutions for the vector-valued elliptic-parabolic variational inequality with time-dependent constraint. Moreover, we give some applications of the system, for example, time-dependent boundary obstacle problem and time-dependent interior obstacle problem. (C) 2011 Elsevier Inc. All rights reserved.

    DOI

  • Variational inequalities for a non-isothermal phase field model

    Kota Kumazaki, Masahiro Kubo

    Discrete and Continuous Dynamical Systems - Series S   4 ( 2 ) 409 - 421   2011.04  [Refereed]

    　View Summary

    We study variational inequalities for a non-isothermal phase field model of the Penrose-Fife type. We consider time-dependent constraints for the order parameter and the Dirichlet boundary condition for the temperature.

    DOI

  • Variational inequalities with time-dependent constraints in L-p

    Masahiro Kubo

    NONLINEAR ANALYSIS-THEORY METHODS & APPLICATIONS ( PERGAMON-ELSEVIER SCIENCE LTD )  73 ( 2 ) 390 - 398   2010.07  [Refereed]

    　View Summary

    We propose an abstract variational inequality with time-dependent constraints in a Banach space with a uniformly convex dual and establish the existence, uniqueness, and regularity of the solution thereof. The abstract result is applied to concrete variational inequalities with time-dependent constraints, thereby obtaining the L-p-regularity of solutions. (C) 2010 Elsevier Ltd. All rights reserved.

    DOI

  • A system of evolution equations for non-isothermal phase transitions

    Masahiro Kubo, Kota Kumazaki

    JOURNAL OF EVOLUTION EQUATIONS ( BIRKHAUSER VERLAG AG )  10 ( 1 ) 129 - 145   2010.03  [Refereed]

    　View Summary

    We propose and study a system of evolution equations. This is an abstract formulation of problems arising in non-isothermal phase transitions. We consider time-dependent constraints on the unknown functions. Thus the problem yields a system of parabolic variational inequalities. We prove the existence of a solution in a general framework, and then apply the abstract result to some models of phase transitions.

    DOI

  • Global attractor of double obstacle problem in thermohydraulics

    Takeshi Fukao, Masahiro Kubo

    GAKUTO International Series. Mathematical Sciences and Applications   32   273 - 287   2010.02  [Refereed]

  • A non-isothermal phase separation with constraints and Dirichlet boundary condition for temperature

    Kota Kumazaki, Akio Ito, Masahiro Kubo

    NONLINEAR ANALYSIS-THEORY METHODS & APPLICATIONS ( PERGAMON-ELSEVIER SCIENCE LTD )  71 ( 5-6 ) 1950 - 1963   2009.09  [Refereed]

    　View Summary

    We consider non-isothermal phase separation models of the Penrose-Fife type, which were proposed in [O. Penrose, P.C. Fife, Thermodynamically consistent models of phase-field type for the kinetics of phase transitions, Physica D 43 (1990) 44-62]. In the present paper, we impose a non-homogeneous Dirichlet boundary condition on the nonlinear heat flux. Moreover, we consider two cases as boundary conditions for the conserved order parameter. One is the homogeneous Neumann boundary condition and the other is the Signorini boundary condition, which is nonlinear.
    We show the existence and uniqueness of solutions to these models. (C) 2009 Elsevier Ltd. All rights reserved.

    DOI

  • Generalized solutions of a non-isothermal phase separation model

    K. Kumazaki, A. Ito, M. Kubo

    Discrete and Continuous Dynamical Systems supplement   2009   476 - 485   2009.09  [Refereed]

  • Time-dependent obstacle problem in thermohydraulics

    T. Fukao, M. Kubo

    Discrete and Continuous Dynamical Systems supplement   2009   240 - 249   2009.09  [Refereed]

  • Singular perturbations for variational inequalities with time-dependent constraints

    Masahiro Kubo

    JOURNAL OF MATHEMATICAL ANALYSIS AND APPLICATIONS ( ACADEMIC PRESS INC ELSEVIER SCIENCE )  356 ( 1 ) 60 - 68   2009.08  [Refereed]

    　View Summary

    We study an abstract hyperbolic variational inequality with a (small) parameter and with time-dependent subdifferentials in a real Hilbert space. We prove that its Solution converges to a solution of a parabolic variational inequality as the parameter tends to zero. We also explain how to apply the abstract theory to concrete unilateral problems. (C) 2009 Elsevier Inc. All rights reserved.

    DOI

  • Convergence and optimal control problems for elliptic-parabolic variational inequalities with time-dependent constraints

    M. Kubo, N. Yamazaki

    Advances in Mathematical Sciences and Applications   19 ( 1 ) 155 - 183   2009.07  [Refereed]

  • Time-dependent double obstacle problem in thermohydraulics

    Takeshi Fukao, Masahiro Kubo

    GAKUTO International Series. Mathematical Sciences and Applications   29   73 - 92   2008.08  [Refereed]

  • Well-posedness for an extended Penrose-Fife phase-field model with energy balance supplied by Dirichlet boundary conditions

    Akio Ito, Masahiro Kubo

    NONLINEAR ANALYSIS-REAL WORLD APPLICATIONS ( PERGAMON-ELSEVIER SCIENCE LTD )  9 ( 2 ) 370 - 383   2008.04  [Refereed]

    　View Summary

    In this study we consider the non-isothermal phase-field model proposed by Penrose and Fife [Thermodynamically consistent models of phase-field type for the kinetics of phase transitions, Physica D 43 (1990) 44-62]. The system consists of the energy balance law (a nonlinear heat equation) and an equation that describes space-time changes in the order parameter (the Ginzburg-Landau equation). For the energy balance law, we consider the general nonlinear heat flux arising in non-equilibrium thermodynamics and impose the Dirichlet boundary condition. For the order parameter, we impose a constraint and thus consider a parabolic variational inequality. We prove the well-posedness of the problem: the system yields a unique solution that depends continuously upon given data. (c) 2007 Elsevier Ltd. All rights reserved.

    DOI

  • Well-posedness and periodic stability for quasilinear parabolic variational inequalities with time-dependent constraints

    Ken Shirakawa, Masahiro Kubo, Noriaki Yamazaki

    Recent Advances in Nonlinear Analysis, World Scientific ( World Scientific Publishing Co. )    181 - 196   2008.01  [Refereed]

    　View Summary

    In this paper, we deal with Cauchy problems for some quasilinear parabolic variational inequalities subject to time-dependent constraints. With re- gard to this type of problem, the authors of [8] recently developed a general theory concerned with the existence and uniqueness of solutions. The main objective of this paper is to study the key-properties of dynamical systems generated by our Cauchy problems. To this end, we first prove the well-posedness (including con- tinuous dependence) of solutions on the basis of the earlier work [8]. Eventually, we focus on the periodic situation of dynamical systems, to validate the results concerned with the existence of periodic solutions, and the asymptotic stability from the viewpoint of attractors.

    DOI

  • Elliptic-parabolic variational inequalities with time-dependent constraints

    Masahiro Kubo, Noriaki Yamazaki

    DISCRETE AND CONTINUOUS DYNAMICAL SYSTEMS ( AMER INST MATHEMATICAL SCIENCES )  19 ( 2 ) 335 - 359   2007.10  [Refereed]

    　View Summary

    We study variational inequalities for quasilinear elliptic-parabolic equations with time-dependent constraints. Introducing a general condition for the time-dependence of convex sets defining the constraints, we establish theorems concerning existence, uniqueness as well as an order property of solutions. Some applications of the general results are given.

  • Nonlinear degenerate parabolic equations for a thermohydraulic model

    T. Fukao, M. Kubo

    Discrete and Continuous Dynamical Systems supplement   2007   399 - 408   2007.09  [Refereed]

  • Periodic stability of elliptic-parabolic variational inequalities with time-dependent boundary double obstacles

    M. Kubo, N. Yamazaki

    Discrete and Continuous Dynamical Systems supplement   2007   614 - 623   2007.09  [Refereed]

  • Optimal control problems for models of phase-field type with hysteresis of play operator

    K.-H. Hoffmann, N. Kenmochi, M. Kubo, N.Yazamaki

    Advances in Mathematical Sciences and Applications   17 ( 1 ) 305 - 336   2007.01  [Refereed]

  • Second order evolution equations with time-dependent subdifferentials

    Masahiro Kubo

    JOURNAL OF EVOLUTION EQUATIONS ( BIRKHAUSER VERLAG AG )  7 ( 4 ) 701 - 717   2007  [Refereed]

    　View Summary

    We study an abstract second order nonlinear evolution equation in a real Hilbert space. We consider time-dependent convex functions and their subdifferentials operating on the first derivative of the unknown function. Introducing appropriate assumptions on the convex functions and other data, we prove the existence and uniqueness of a strong solution, and give some applications of the abstract theorem to hyperbolic variational inequalities with time-dependent constraints.

    DOI

  • Optimal control problems for elliptic-parabolic variational inequalities with time-dependent constraints

    Karl-Heinz Hoffmann, Masahiro Kubo, Noriaki Yamazaki

    Numerical Functional Analysis and Optimization   27 ( 3-4 ) 329 - 356   2006.08  [Refereed]

    　View Summary

    In this paper, we study optimal control problems for quasi-linear elliptic-parabolic variational inequalities with time-dependent constraints. We prove the existence of an optimal control that minimizes the nonlinear cost functional. Moreover, we apply our general results to some model problems. In particular, we show the necessary condition of optimal pair for a problem of partial differential equation (PDE) with a non-homogeneous Dirichlet boundary condition. Copyright © 2006 Taylor &amp
    Francis Group, LLC.

    DOI

  • Weak solutions of a thermohydraulics model with a general nonlinear heat flux

    Masahiro Kubo

    GAKUTO International Series. Mathematical Sciences and Applications   23   163 - 178   2006.06  [Refereed]

  • Evolution equations for nonlinear degenerate parabolic PDE

    M Kubo, QQ Lu

    NONLINEAR ANALYSIS-THEORY METHODS & APPLICATIONS ( PERGAMON-ELSEVIER SCIENCE LTD )  64 ( 8 ) 1849 - 1859   2006.04  [Refereed]

    　View Summary

    We define a convex function on H-1 (Omega) and characterize its subdifferential, by which we introduce an evolution equation as a weak formulation of a class of nonlinear, degenerate, singular and noncoercive parabolic PDEs associated with an arbitrary maximal monotone graph and with the Dirichlet boundary condition. (c) 2005 Elsevier Ltd. All rights reserved.

    DOI

  • Periodic solutions of elliptic-parabolic variational inequalities with time-dependent constraints

    M Kubo, N Yamazaki

    JOURNAL OF EVOLUTION EQUATIONS ( BIRKHAUSER VERLAG AG )  6 ( 1 ) 71 - 93   2006.02  [Refereed]

    　View Summary

    We study periodic solutions of quasilinear elliptic-parabolic variational inequalities with time-dependent constraints. Assuming that the constraint changes periodically in time, we prove existence of periodic solutions. Moreover, applications of the general results are given.

    DOI

  • Subdifferential operator approach to the Dirichlet problem of nonlinear degenerate parabolic equations

    Akio Ito, Masahiro Kubo, Quqin Lu

    Differential and Difference Equations and Applications (R. P. Agarwal et al eds.), Hindawi, New York     441 - 450   2006.01  [Refereed]

  • Well-posedness of initial boundary value problem of degenerate parabolic equations

    Masahiro Kubo

    NONLINEAR ANALYSIS-THEORY METHODS & APPLICATIONS ( PERGAMON-ELSEVIER SCIENCE LTD )  63 ( 5-7 ) E2629 - E2637   2005.11  [Refereed]

    　View Summary

    We study a nonlinear degenerate parabolic equation associated with an arbitrary maximal monotone graph. We impose initial and Dirichlet boundary conditions and prove that the problem is well-posed. (C) 2005 Elsevier Ltd. All rights reserved.

    DOI

  • Nonlinear degenerate parabolic equations with Neumann boundary condition

    M Kubo, Q Lu

    JOURNAL OF MATHEMATICAL ANALYSIS AND APPLICATIONS ( ACADEMIC PRESS INC ELSEVIER SCIENCE )  307 ( 1 ) 232 - 244   2005.07  [Refereed]

    　View Summary

    We study Neumann problem for a class of nonlinear degenerate parabolic PDE. A typical nonlinearity we have in mind is, for instance, β(u) = -1/u (u > 0). We establish a necessary and sufficient condition on given data for existence of solution. © 2004 Elsevier Inc. All rights reserved.

    DOI

  • Quasilinear parabolic variational inequalities with time-dependent constraints

    M. Kubo, N. Yamazaki

    Advances in Mathematical Sciences and Applications   15 ( 1 ) 335 - 354   2005.01  [Refereed]

  • A filtration model with hysteresis

    M Kubo

    JOURNAL OF DIFFERENTIAL EQUATIONS ( ACADEMIC PRESS INC ELSEVIER SCIENCE )  201 ( 1 ) 75 - 98   2004.06  [Refereed]

    　View Summary

    We study a filtration model for which a hysteresis effect is accounted in the saturation versus pressure constitutive relation. The problem is formulated in a quasi-variational inequality. We prove the existence of a time global solution. (C) 2004 Elsevier Inc. All rights reserved.

    DOI

  • Non-isothermal phase transition models with Neumann boundary conditions

    A Ito, N Kenmochi, M Kubo

    NONLINEAR ANALYSIS-THEORY METHODS & APPLICATIONS ( PERGAMON-ELSEVIER SCIENCE LTD )  53 ( 7-8 ) 977 - 996   2003.06  [Refereed]

    　View Summary

    We study the systems of nonlinear parabolic PDEs for Penrose-Fife models of non-isothermal phase transitions. Both models with conserved and non-conserved order parameters are studied with Neumann boundary conditions imposed on the systems in multi-dimensional spatial domain. (C) 2003 Elsevier Science Ltd. All rights reserved.

    DOI

  • Well-posedness and attractors of phase transition models with constraint

    M Kubo, A Ito, N Kenmochi

    NONLINEAR ANALYSIS-THEORY METHODS & APPLICATIONS ( PERGAMON-ELSEVIER SCIENCE LTD )  47 ( 5 ) 3207 - 3214   2001.08  [Refereed]

    　View Summary

    Results and idea of proofs are presented for the well-posedness and the existence of a global attractor of the Penrose-Fife model of non-isothermal phase transitions. Models with conserved and non-conserved order parameters, on which a constraint is posed, are treated.

    DOI

  • A phase-field model with temperature dependent constraint

    P Colli, N Kenmochi, M Kubo

    JOURNAL OF MATHEMATICAL ANALYSIS AND APPLICATIONS ( ACADEMIC PRESS INC )  256 ( 2 ) 668 - 685   2001.04  [Refereed]

    　View Summary

    This paper is concerned with a phase-held model with temperature dependent constraint for the order parameter. In the kinetic equation of the order parameter, we take account of diffusion as well as the undercooled/superheated state which is modelled by means of a hysteresis input-output relation; the input is the temperature held and the output is the order parameter. In this paper we shall show that there exists a solution "globally" in time in a physically reasonable sense, when the coefficient of interfacial energy is sufficiently small. (C) 2001 Academic Press.

    DOI

  • Non-isothermal phase separation models: construction of attractors.: weak well-posedness and global estimates

    Akio Ito, Nobuyuki Kenmochi, Masahiro Kubo

    GAKUTO International Series. Mathematical Sciences and Applications   13   137 - 152   2000.03  [Refereed]

  • Global attractors of phase transition models with hysteresis and diffusion effects

    Noriaki Yamazaki, Masato Takahashi, Masahiro Kubo

    GAKUTO International Series. Mathematical Sciences and Applications   14   460 - 471   2000.03  [Refereed]

  • Non-isothermal phase separation models: weak well-posedness and global estimates

    Masahiro Kubo, Akio Ito, Nobuyuki Kenmochi

    GAKUTO International Series. Mathematical Sciences and Applications ( Gakkotosho Co., Ltd. )  14   311 - 323   2000.03  [Refereed]

  • Weak solutions of novlinear systems for non-isothermal phase transitions

    N. Kenmochi, M. Kubo

    Advances in Mathematical Sciences and Applications   9 ( 1 ) 499 - 521   1999.04  [Refereed]

  • Well-posedness for a phase-field model with constraint

    N Kenmochi, M Kubo

    FREE BOUNDARY PROBLEMS: THEORY AND APPLICATIONS, Chapman & Hall/CRC Res. Notes Math. ( CHAPMAN & HALL/CRC PRESS )  409   147 - 154   1999  [Refereed]

    　View Summary

    A phase-field model with constraint of the Penrose-Fife type is considered. The model is a system of nonlinear parabolic PDEs which governs the (absolute) temperature and order parameter with bounded constraint. In this paper, the well-posedness of the system is shown in the product space of the dual of H-1(Omega) and L-2(Omega).

  • PERIODIC-SOLUTIONS FOR NONLINEAR POPULATION-DYNAMICS MODELS WITH AGE-DEPENDENCE AND SPATIAL STRUCTURE

    M KUBO, M LANGLAIS

    JOURNAL OF DIFFERENTIAL EQUATIONS ( ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS )  109 ( 2 ) 274 - 294   1994.04  [Refereed]

  • Periodic solutions for nonlinear population dynamics models with periodic supply

    Masahiro Kubo, Michel Langlais

    Pitman Research Notes in Mathematics Series   267   214 - 220   1992.01  [Refereed]

  • PERIODIC-SOLUTIONS FOR A POPULATION-DYNAMICS PROBLEM

    M KUBO, M LANGLAIS

    COMPTES RENDUS DE L ACADEMIE DES SCIENCES SERIE I-MATHEMATIQUE ( GAUTHIER-VILLARS )  313 ( 6 ) 387 - 390   1991.09  [Refereed]

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    First we consider a partial differential equation arising in population dynamics problem with age dependence and spatial structure. The birth and death processes are nonlinear, with nonlocal nonlinearities. We give existence and nonexistence results for time periodic solutions under a time periodic supply of individuals. Next we prove the existence of time periodic solutions for the corresponding S-I-R-S epidemic model.

  • Some variational inequalities for age-dependent population dynamics

    Masahiro Kubo

    Japan Journal of Industrial and Applied Mathematics   8 ( 2 ) 275 - 296   1991.06  [Refereed]

    　View Summary

    A variational inequality for an equation of age-dependent population diffusion is studied. A mixed-type boundary condition is prescribed on time-and age-dependent parts of the boundary. The rate of mortality is allowed to have a divergency property at the maximal age. © 1991 the JJIAM Publishing Committee.

    DOI

  • PERIODIC-SOLUTIONS FOR A POPULATION-DYNAMICS PROBLEM WITH AGE-DEPENDENCE AND SPATIAL STRUCTURE

    M KUBO, M LANGLAIS

    JOURNAL OF MATHEMATICAL BIOLOGY ( SPRINGER VERLAG )  29 ( 4 ) 363 - 378   1991  [Refereed]

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    Using a linear model with age-dependence and spatial structure we show how a periodical supply of individuals will transform an exponentially decaying distribution of population into a non-trivial asymptotically stable periodic distribution. Next we give an application to an epidemic model.

  • PERIODIC-SOLUTIONS OF PARABOLIC-ELLIPTIC OBSTACLE PROBLEMS

    N KENMOCHI, M KUBO

    JOURNAL OF DIFFERENTIAL EQUATIONS ( ACADEMIC PRESS INC ELSEVIER SCIENCE )  88 ( 2 ) 213 - 237   1990.12  [Refereed]

  • Periodic solutions to porous media equations of parabolic-elliptic type

    N. Kenmochi, D. Kröner, M. Kubo

    Journal of Partial Differential Equations   3 ( 3 ) 63 - 77   1990.07  [Refereed]

  • PERIODIC STABILITY OF FLOW IN PARTIALLY SATURATED POROUS-MEDIA

    N KENMOCHI, M KUBO

    FREE BOUNDARY VALUE PROBLEMS, Internat. Ser. Numer. Math. ( BIRKHAUSER VERLAG )  95   127 - 152   1990  [Refereed]

  • PERIODIC BEHAVIOR OF SOLUTIONS TO PARABOLIC-ELLIPTIC FREE-BOUNDARY PROBLEMS

    N KENMOCHI, M KUBO

    JOURNAL OF THE MATHEMATICAL SOCIETY OF JAPAN ( MATH SOC JAPAN )  41 ( 4 ) 625 - 640   1989.10  [Refereed]

  • Characterization of a class of evolution operators generated by time-dependent subdifferentials

    M. Kubo

    Funkcialaj Ekvacioj   32 ( 2 ) 301 - 321   1989.08  [Refereed]

  • Periodic and almost periodic stability of solutions to degenerate parabolic equations

    M. Kubo

    Hiroshima Mathematical Journal   19 ( 3 ) 499 - 514   1989.07  [Refereed]

  • Periodic behaviour of solutions to a parabolic-elliptic problem

    Nobuyuki Kenmochi, Masahiro Kubo

    Pitman Research Notes in Mathematics Series   208   68 - 76   1989.03  [Refereed]

  • Subdifferential operator approach to nonlinear age-dependent population dynamics

    Masahiro Kubo

    Japan Journal of Applied Mathematics   5 ( 2 ) 225 - 256   1988.06  [Refereed]

    　View Summary

    Some obstacle problems, arising in age-dependent population dynamics, have been studied by Garroni-Lamberti [3] and Garroni-Langlais [4]. In this paper, we shall study abstract evolution equations associated with these obstacle, problems from the viewpoint of the subdifferential operator theory. Existence and uniqueness theorems will be established by using some results of the theory of evolution equations generated by time-dependent subdifferentials. Also, problems with monotone perturbations will be solved. Moreover, in the final section we apply the abstract results to two nonlinear evolution problems arising in population dynamics. © 1988 JJAM Publishing Committee.

    DOI

  • Periodicity of solutions to some parabolic-elliptic variational inequalities

    久保雅弘

    非線形発展方程式と偏微分方程式 数理解析研究所講究録   647   148 - 160   1988.02  [Invited]

  • Periodic solutions to a class of nonlinear variational inequalities with time-dependent constraints

    N. Kenmochi, M. Kubo

    Funkcialaj Ekvacioj   30 ( 2-3 ) 333 - 349   1987.07  [Refereed]

  • Periodicity and almost periodicity of solutions to free boundary problems in Hele-Shaw flows

    M. Kubo

    Proceedings of the Japan Academy Series A Mathematical Sciences   62 ( 8 ) 288 - 291   1986.08  [Refereed]

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Misc

  • ある障害物問題の時間局所・大域解と大域的アトラクターについて

    深尾 武史, 久保 雅弘

    日本数学会 2009 年度秋季総合分科会 実関数論分科会 アブストラクト ( 日本数学会 )    67 - 68   2009.09

  • 熱水力学に現れるある障害物問題の弱解と漸近挙動について

    深尾 武史, 久保 雅弘

    日本数学会 2009 年度年会 実関数論分科会 アブストラクト     17 - 18   2009.03

  • 熱水力学に現れるある障害物問題の弱解と漸近挙動について

    深尾 武史, 久保 雅弘

    第34回発展方程式研究会 発表論文集     53 - 54   2008.12

  • 熱水力学に現れるある変分不等式について

    深尾 武史, 久保 雅弘

    日本数学会 2008 年度秋季総合分科会 実関数論分科会 アブストラクト     53 - 54   2008.09

  • 熱水力学に現れるある変分不等式と解の正則性について

    深尾 武史, 久保 雅弘

    日本数学会 2008 年度年会 実関数論分科会 アブストラクト     15 - 16   2008.03

  • 熱水力学に現れる退化放物型方程式系の可解性について

    深尾 武史, 久保 雅弘

    日本数学会 2006 年度年会 実関数論分科会 アブストラクト     44 - 45   2006.03

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Conference Activities & Talks

  • Elliptic-parabolic quasi-variational evolution equations

    久保雅弘, 山崎教昭

    日本数学会2023年度秋季総合分科会  2023.09.23  

  • （企画特別講演）時間依存劣微分発展方程式と準変分発展方程式

    久保雅弘  [Invited]

    日本数学会2022年度年会  2022.03.30  

  • Elliptic-parabolic quasi-subdifferential evolution equations

    Masahiro Kubo  [Invited]

    Workshop on Mathematical Methods and Applications with Nonlinear Evolution Equations  2019.08.17  

  • Quasi-variational principles and quasi-subdifferential operators

    Masahiro Kubo  [Invited]

    The 5th Polish Japanese Days on Nonlinear Analysis in Interdisciplinary Sciences - Modellings, Theory and Simulations -  2012.11  

  • A new class of nonlinear evolution equations

    Masahiro Kubo  [Invited]

    The 9th AIMS Conference on Dynnamical Systems, Differential Equations and Applications  2012.07  

  • （特別講演）非線形発展方程式と変分不等式の特異摂動,

    久保雅弘  [Invited]

    日本数学会2009年度秋季総合分科会  2009.09.25  

  • A class of quasi-variational inequalities for hysteresis

    Masahiro Kubo  [Invited]

    The 6th AIMS Conference on Dynnamical Systems, Differential Equations and Applications  2006.06.25  

  • Subdifferential operator approach to a class of nonlinear degenerate parabolic equations

    Masahiro Kubo  [Invited]

    Conference on Differential & Difference Equations  2005.08.01  

  • Weak solutions of the Boussinesq system with nonlinear degenerate heat flux

    Masahiro Kubo  [Invited]

    The 3rd Polish Japanese Days "Mathematical Approach to Nonlinear Phenomena"  2004.11.30  

  • Initial boundary value problems of nonlinear degenerate parabolic equations

    Masahiro Kubo  [Invited]

    The 4th World Congress of Nonlinear Analysts  2004.07.05  

  • Attractors of phase transition models with constraint

    Masahiro Kubo  [Invited]

    The 3rd World Congress of Nonlinear Analysts  2000.07  

  • Periodicity of saturated-unsaturated flow in porous medium

    Masahiro Kubo  [Invited]

    Freie Randwertaufgaben  1989.07  

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KAKENHI

  • 非線形発展方程式と準変分解析

    2014.04
    -
    2019.03
     

    Grant-in-Aid for Scientific Research(C)  Principal investigator

Committee member history in academic associations, government agencies, municipalities, etc.

  • 委員

    2024.03.01
    -
    2025.02.28
     

    日本数学会

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    学協会、政府、自治体等の公的委員

    代議員（阪神地区）,任期:1年

  • 委員

    2022.03
    -
    2023.02
     

    日本数学会

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    学協会、政府、自治体等の公的委員

    代議員（阪神地区）,任期:1年

  • 委員

    2018.03
    -
    2019.02
     

    日本数学会

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    学協会、政府、自治体等の公的委員

    代議員（阪神地区）,任期:1年

  • 委員

    2016.03
    -
    2017.02
     

    日本数学会

    　View Details

    学協会、政府、自治体等の公的委員

    代議員（阪神地区）,任期:1年