Positive solutions of a diffusive logistic equation with a non Lipschitz boundary condition arising in coastal fishery harvesting
Kenichiro Umezu
Division of Functional Equations, The 2020 Annual Meeting of MSJ, 18 Mar. 2025, MSJ
20250318, 20250321
Positive solutions for logistic type elliptic equation with a non Lipschitz boundary condition arising in coastal fishery harvesting
Kenichiro Umezu
Equadiff2024 in Karlstad, 13 Jun. 2024
20240610, 20240614
Positive solutions for some sublinear Robin problem with an indefinite weight
Kenichiro Umezu
The Friday Seminar of Ibaraki University, 07 Jul. 2023, [Invited]
20230707, 20230707
An exact multiplicity result for some sublinear Robin problem with an indefinite weight
Kenichiro Umezu
The 13th AIMS Conference on Dynamical Systems, Differential Equations and Applications in Wilmington NC, 01 Jun. 2023, AIMS(American Institute of Mathematical Sciences), [Invited]
20230531, 20230604
Logistic elliptic equations with the nonlinear boundary condition arising in coast fishery harvesting
Kenichiro Umezu
The Applied Mathematical Analysis Seminar of Tohoku University, 09 Jun. 2022, 東北大学大学院理学研究科数学教室, [Invited]
Uniqueness of a positive solution for the Laplace equation with indefinite superlinear boundary conditions: near a critical case
Kenichiro Umezu
The South Osaka Applied Mathematics Seminar, 11 Dec. 2021, 大阪市立大学理学研究科, [Invited]
Global exact multiplicity of positive solutions for an indenite sublinear Robin problem
Kenichiro Umezu
Division of Functional Equations, The 2020 Annual Meeting of MSJ, 16 Mar. 2020, 日本数学会
Existence of a loop of positive solutions for concave-convex problems with indefinite weights
Kenichiro Umezu
Equadiff 2019 in Leiden, 11 Jul. 2019
Exact multiplicity of positive solutions for an indefinite concave Robin bvp
Kenichiro Umezu
Division of Functional Equations, The 2019 Annual Meeting of MSJ, 17 Mar. 2019, 日本数学会
Positivity of bifurcating nontrivial nonnegative solutions of indefinite concave problems
Kenichiro Umezu
The 12th AIMS Conference on Dynamical Systems, Differential Equations and Applications in Taipei, 06 Jul. 2018, American Institute of Mathematical Sciences, [Invited]
Loop components of nontrivial nonnegative solutions for indefinite concave-convex problems
Kenichiro Umezu
Division of Functional Equations, The 2018 Annual Meeting of MSJ, 18 Mar. 2018, 日本数学会
Subcontinua of loop for positive solutions to concave-convex elliptic boundary value problems
Kenichiro Umezu
Variation Problem Seminar of Tokyo Metropolitan University, 14 Dec. 2017, 首都大学東京理工学研究科数理情報科学専攻, [Invited]
Positivity for nontrivial nonnegative solutions of an indefinite sublinear problem
Kenichiro Umezu
Division of Functional Equations, The 2017 Annual Meeting of MSJ, 24 Mar. 2017, 日本数学会
On the existence of a loop component of nontrivial non-negative solutions for some concave-convex problem
Kenichiro Umezu
Workshop on reaction diffusion equations and numerical analysis (Kyoto Sangyo University), 08 Oct. 2016, [Invited]
A loop type component of positive solutions of an indefinite concave-convex problem with the Neumann boundary condition
Kenichiro Umezu
The 11th AIMS Conference on Dynamical Systems, Differential Equations and Applications in Orlando, 04 Jul. 2016, American Institute of Mathematical Sciences (AIMS), [Invited]
An indefinite superlinear elliptic equation with a nonlinear boundary condition of sublinear type
Kenichiro Umezu
RIMS Workshop `Shapes and other properties of solutions of PDEs' (RIMS, Kyoto University), 13 Nov. 2015, [Invited]
Bifurcation analysis for a logistic elliptic equation having nonlinear boundary conditions with sign-definite weights
Kenichiro Umezu
Seminar of Department of Mathematics, Universidad de Santiago de Chile, 01 Sep. 2015, Department of Mathematics, Universidad de Santiago de Chile, [Invited]
Role of indefinite weights for the structure of the solution set of concave-convex mixed boundary value problems
Kenichiro Umezu
Division of Functional Equations, The 2015 Annual Meeting of MSJ, 21 Mar. 2015, 日本数学会
The effect of a nonlinear boundary condition with an indefinite weight on the positive solution set of the logistic elliptic equation
Kenichiro Umezu
The 10th AIMS Conference on Dynamical Systems, Differential Equations and Applications in Madrid, 08 Jul. 2014, AIMS(American Institute of Mathematical Sciences), [Invited]
On S-shaped and CS-shaped bifurcation diagrams in population dynamics
Kenichiro Umezu
Division of Functional Equations, The 2014 Annual Meeting of MSJ, 17 Mar. 2014, 日本数学会
On the effect of spatial heterogeneity in logistic type elliptic equations with nonlinear boundary conditions
Kenichiro Umezu
The 9th AIMS Conference on Dynamical Systems, Differential Equations and Applications in Orlando, 04 Jul. 2012, American Institute of Mathematical Sciences, [Invited]
Global structure of bifurcation for positive solutions to nonlinear elliptic boundary value problems of logistic type
Kenichiro Umezu
Variation Problem Seminar of Tokyo Metropolitan University, 09 Mar. 2012, 首都大学東京理工学研究科数理情報科学専攻, [Invited]
Global bifurcation of positive solutions for some elliptic problems with nonlinear boundary conditions
Kenichiro Umezu
Toya Analysis Seminar, 28 Sep. 2010, [Invited]
Global bifurcation analysis of indefinite nonlinear boundary value problems with nonlinear boundary conditions
Kenichiro Umezu
The 8th AIMS Conference on Dynamical Systems, Differential Equations and Applications in Dresden, 27 May 2010, American Institute of Mathematical Sciences, [Invited]
Global bifurcation for indefinite weighted elliptic problems with nonlinear boundary conditions
Kenichiro Umezu
Division of Functional Equations, The 2010 Annual Meeting of MSJ, 25 Mar. 2010, 日本数学会
A super and subsolution method for sublinear problems with low regularity coefficients
Kenichiro Umezu
Division of Functional Equations, The 2008 Annual Meeting of MSJ in Autumn, 25 Sep. 2008, 日本数学会
Blowing-up properties of the positive principal eigenvalue for indefinite Robin-type boundary conditions
Kenichiro Umezu
The Second China-Japan Colloquium of Mathematical Biology in Okayama, 06 Aug. 2008
Nehari manifolds, fibering maps and semilinear elliptic boundary value problems
Kenichiro Umezu
Mathematical Science Seminar, 10 Sep. 2007
Multiplicity of positive solutions to nonlinear elliptic boundary value problems arising in population dynamics
Kenichiro Umezu
Workshop "Direct, Inverse And Control Problems For PDE's" in Rome, 27 Jun. 2007
Principal eigenvalues of Neumann and Robin type eigenvalue problems with indefinite weights
Kenichiro Umezu
The 4th International Conference on Mathematical Biology in Wuyishan, 01 Jun. 2007, [Invited]
Principal eigenvalues and population dynamics
Kenichiro Umezu
Division of Functional Equations, The 2007 Annual Meeting of MSJ, 28 Mar. 2007, 日本数学会
Blowing-up principal eigenvalues of Neumann eigenvalue problems with indefinite weights
Kenichiro Umezu
Analysis Seminar (Institute of Math., University of Tsukuba), 20 Dec. 2006, 筑波大学数学系
Principal eigenvalues for Neumann boundary conditions
Kenichiro Umezu
Applied Analysis Seminar (Waseda University), 02 Dec. 2006, 早稲田大学理工学部数学科
Principal eigenvalues for Neumann boundary conditions
Kenichiro Umezu
Mathematical Science Seminar, 10 Sep. 2006
Blowing-up behavior of principal eigenvalues for Neumann boundary conditions
Kenichiro Umezu
The first China-Japan Colloquium of Mathematical Biology (CJCMB) in Chongqing, 25 Apr. 2006
Principal eigenvalues for Robin boundary conditions
Kenichiro Umezu
Division of Functional Equations, The 2006 Annual Meeting of MSJ, 27 Mar. 2006, 日本数学会
Elliptic eigenvalue problems with indefinite Robin boundary conditions
Kenichiro Umezu
ISAAC05, the 5th Congress in Catania, 29 Jul. 2005, [Invited]
An estimate for turning points in sublinear elliptic boundary value problems
Kenichiro Umezu
Division of Functional Equations, The 2005 Annual Meeting of MSJ, 28 Mar. 2005, 日本数学会
Stationary solutions of diffusive logistic equations with large diffusion and nonlinear boundary conditions
Kenichiro Umezu
Mathematical Science Seminar, 18 Jul. 2004
Existence and nonexistence of positive solutions for a semilinear elliptic problem arising in population dynamics
Kenichiro Umezu
Nonlinear Elliptic and Parabolic Problems: A Special Tribute to the Work of Herbert Amann in Zurich, 30 Jun. 2004
Existence and limiting behavior of positive solutions for diffusive logistic equations with nonlinear flux on the boundary
Kenichiro Umezu
Division of Functional Equations, The 2003 Annual Meeting of MSJ in Autumn, 27 Sep. 2003, 日本数学会
Multiplicity and behavior of positive solutions to nonlinear elliptic equations arising in population dynamics
Kenichiro Umezu
Colloquium of Institute of Mathematics, University of Tsukuba, 04 Sep. 2003, 筑波大学数学系
On diffusive logistic equations having nonlinear boundary conditions
Kenichiro Umezu
ISAAC03, the 4th Congress in Toronto, Aug. 2003, ISAAC, [Invited]
Multiplicity of positive solutions to a nonlinear elliptic boundary value problem arising in population dynamics
Kenichiro Umezu
Variation Problem Seminar of Tokyo Metropolitan University, Feb. 2003, 東京都立大学理学部数学教室, [Invited]
Bifurcation analysis of a semilinear elliptic problem arising in population dynamics and having nonlinear boundary conditions
Kenichiro Umezu
Mathematical Analysis for Self-Interacting Particle System, Nov. 2002, 大阪大学基礎工学部, [Invited]
Bifurcation problem for a semilinear elliptic equation arising in population dynamics, having nonlinear boundary conditions
Kenichiro Umezu
International Conference on Nonlinear Partial Differential Equations Theory and Approximation in Hong Kong, Aug. 2002
Local and global bifurcation analysis on a nonlinear problem from population
Kenichiro Umezu
Mathematical Science Seminar, Jun. 2002
Global subcontinua arising in population dynamics
Kenichiro Umezu
Division of Functional Equations, The 2002 Annual Meeting of MSJ, Mar. 2002, 日本数学会
Bifurcation in population dynamics
Kenichiro Umezu
The 4th European Conference on Elliptic and Parabolic Problems in Gaeta, Sep. 2001
Bifurcation analysis in diffusive logistic equations with nonlinear boundary conditions
Kenichiro Umezu
ISAAC01, the 3rd Congress in Berlin, Aug. 2001, ISAAC, [Invited]
Bifurcation on nonlinear eigenvalue problems in population dynamics
Kenichiro Umezu
Analysis Seminar (Institute of Math., University of Tsukuba), May 2001, 筑波大学数学系
Bifurcation in Population Genetics
Kenichiro Umezu
Division of Functional Equations, The 2001 Annual Meeting of MSJ, Mar. 2001, 日本数学会
Bifurcation in population models
Kenichiro Umezu
Biological phenomena and nonlinear differential equations (Hiroshima University), Sep. 2000
Diffusive logistic equations with indefinite weights and nonlinear boundary ,conditions
Kenichiro Umezu
Mathematical Science Seminar, May 2000
Positive solutions for population model under a nonlinear boundary condition
Kenichiro Umezu
Division of Functional Equations, The 2000 Annual Meeting of MSJ, Mar. 2000, 日本数学会
Bifurcation from infinity and uniqueness of positive solutions to semilinear elliptic equations with nonlinear boundary conditions
Kenichiro Umezu
Division of Functional Equations, The 2000 Annual Meeting of MSJ, Mar. 2000, 日本数学会
Positive solutions for population model under a nonlinear boundary condition
Kenichiro Umezu
Biological phenomena and nonlinear differential equations (Hiroshima University), Nov. 1999
Bifurcation and stability for diffusive logistic equations with nonlinear boundary conditions
Kenichiro Umezu
International Conference on Nonlinear Partial Differential Equations 99 in Lviv, Aug. 1999
Elliptic boundary value problems with nonlinear boundary conditions
Kenichiro Umezu
ICIAM 99, the 4th Congress in Edinburgh, Jul. 1999, ICIAM, [Invited]
Diffusive logistic equations with nonlinear boundary conditions
Kenichiro Umezu
Mathematical Science Seminar, Jun. 1999
Asymptotical stability in chemical reactor theory
Kenichiro Umezu
Division of Functional Equations, The 1999 Annual Meeting of MSJ, Mar. 1999, 日本数学会
Nonlinear elliptic boundary value problem arising in fermentation industry
Kenichiro Umezu
Analysis Seminar (Institute of Math., University of Tsukuba), Jan. 1999, 筑波大学数学系
Positive solutions of semilinear elliptic boundary value problems
Kenichiro Umezu
Division of Functional Equations, The 1998 Annual Meeting of MSJ in Autumn, Oct. 1998, 日本数学会
Nonlinear elliptic boundary value problem arising in fermentation industry
Kenichiro Umezu
Biological phenomena and nonlinear differential equations (Hiroshima University), Sep. 1998
Positive solutions of semilinear elliptic boundary value problems
Kenichiro Umezu
Nagano Symposium on partial differential equations, Jul. 1998
Stability in chemical reactor theory
Kenichiro Umezu
Division of Functional Equations, The 1998 Annual Meeting of MSJ, Mar. 1998, 日本数学会
Semilinear elliptic boundary value problem and its application
Kenichiro Umezu
Seminar on partial differential equations, Oct. 1997, 東京都立大学理学部数学教室, [Invited]
Semilinear elliptic boundary value problems in chemical reactor theory
Kenichiro Umezu
Variational problems and related topics (RIMS, Kyoto University), Jun. 1997, RIMS, Kyoto Univ., [Invited]
Semilinear elliptic boundary value problems in chemical reactor theory
Kenichiro Umezu
ISAAC1997, the 1st Congress in Delaware, Jun. 1997, International Society for Analysis, its Applications and Computation, [Invited]
Semilinear elliptic boundary value problem arising in chemical reactor theory
Kenichiro Umezu
Division of Functional Equations, The 1997 Annual Meeting of MSJ, Apr. 1997, 日本数学会
Semilinear elliptic boundary value problem arising in chemical reactor theory
Kenichiro Umezu
Applied Analysis Seminar (Waseda University), Dec. 1996, 早稲田大学理工学部数学科
Fourier multipliers in weighted Lp spaces
Kenichiro Umezu
Real Analysis Symposium in Oita, Nov. 1996
Existence and uniqueness of positive solutions for semilinear elliptic boundary value problems
Kenichiro Umezu
Division of Functional Equations, The 1996 Annual Meeting of MSJ, Apr. 1996, 日本数学会
Existence and uniqueness of positive solutions for semilinear elliptic boundary value problems
Kenichiro Umezu
Seminar on differential equations, Dec. 1995, 早稲田大学理工学部数学科, [Invited]
Existence and uniqueness of positive solutions for semilinear elliptic boundary value problems
Kenichiro Umezu
Division of Functional Equations, The 1995 Annual Meeting of MSJ in Autumn, Sep. 1995, 日本数学会
Positive solutions of semi linear elliptic boundary value problems
Kenichiro Umezu
Kashikojima symposium on partial differential equations, Sep. 1995
Bifurcation for nonlinear elliptic boundary valuer problems
Kenichiro Umezu
Division of Functional Equations, The 1995 Annual Meeting of MSJ, Mar. 1995, 日本数学会
Besov spaces with variable order
Kenichiro Umezu
Function space and its application, Jan. 1994, 筑波大学数学系
L^p approach to mixed boudary value problems of second order
Kenichiro Umezu
Division of Functional Equations, The 1993 Annual Meeting of MSJ in Autumn, Sep. 1993, 日本数学会