• Title/Summary/Keyword: Positive solutions

Search Result 747, Processing Time 0.029 seconds

DYNAMICS OF A MODIFIED HOLLING-TANNER PREDATOR-PREY MODEL WITH DIFFUSION

  • SAMBATH, M.;BALACHANDRAN, K.;JUNG, IL HYO
    • Journal of the Korean Society for Industrial and Applied Mathematics
    • /
    • v.23 no.2
    • /
    • pp.139-155
    • /
    • 2019
  • In this paper, we study the asymptotic behavior and Hopf bifurcation of the modified Holling-Tanner models for the predator-prey interactions in the absence of diffusion. Further the direction of Hopf bifurcation and stability of bifurcating periodic solutions are investigated. Diffusion driven instability of the positive equilibrium solutions and Turing instability region regarding the parameters are established. Finally we illustrate the theoretical results with some numerical examples.

A study on the Physico-chemical Properties of CB-ph. a New Anti-cancer drug

  • Kim, Su-Yoen;Kim, Dae-Duk;Lee, Chi-Ho
    • Proceedings of the PSK Conference
    • /
    • 2002.10a
    • /
    • pp.413.1-413.1
    • /
    • 2002
  • Purpose To investigate the physico-chemical properties of CB-ph [2-benzoyloxycinnamaldehyde], an anticancer drug obtained from Cinnamomum cassia using methylenechloride. and its stability in various aqueous solutions. Results CB-ph was rarely soluble in water but soluble in methanol and very soluble in ether. Kinetic salt effect on degradation of CB-ph in buffer solutions at pH 4.0 and 6$0^{\circ}C$ showed a linear relationship having a positive slope that means reactions between hydronium ions and protonated substrates. (omitted)

  • PDF

FERMAT'S EQUATION OVER 2-BY-2 MATRICES

  • Chien, Mao-Ting;Meng, Jie
    • Bulletin of the Korean Mathematical Society
    • /
    • v.58 no.3
    • /
    • pp.609-616
    • /
    • 2021
  • We study the solvability of the Fermat's matrix equation in some classes of 2-by-2 matrices. We prove the Fermat's matrix equation has infinitely many solutions in a set of 2-by-2 positive semidefinite integral matrices, and has no nontrivial solutions in some classes including 2-by-2 symmetric rational matrices and stochastic quadratic field matrices.

ON KIRCHHOFF TYPE EQUATIONS WITH SINGULAR NONLINEARITIES, SUB-CRITICAL AND CRITICAL EXPONENT

  • Mohammed El Mokhtar Ould El Mokhtar;Saleh Fahad Aljurbua
    • Nonlinear Functional Analysis and Applications
    • /
    • v.29 no.2
    • /
    • pp.419-434
    • /
    • 2024
  • This paper is devoted to the existence of solutions for Kirchhoff type equations with singular nonlinearities, sub-critical and critical exponent. By using the Nehari manifold and Maximum principle theorem, the existence of at least two distinct positive solutions is obtained.

ON A CERTAIN CLASS OF INTEGRAL-FUNCTIONAL EQUATIONS

  • FAGHIH AHMADI, M.
    • Honam Mathematical Journal
    • /
    • v.28 no.3
    • /
    • pp.395-398
    • /
    • 2006
  • In this note, for any given positive integer n, we determine all the continuous solutions f : R ${\rightarrow}$ R of the integral-functional equation $f^n(x)=n_{_o}{^x}f(t)dt$.

  • PDF

EXISTENCE AND UNIQUENESS OF POSITIVE SOLUTIONS FOR A CLASS OF SEMIPOSITONE QUASILINEAR ELLIPTIC SYSTEMS WITH DIRICHLET BOUNDARY VALUE PROBLEMS

  • CUI, ZHOUJIN;YANG, ZUODONG;ZHANG, RUI
    • Journal of applied mathematics & informatics
    • /
    • v.28 no.1_2
    • /
    • pp.163-173
    • /
    • 2010
  • We consider the system $$\{{{-{\Delta}_pu\;=\;{\lambda}f(\upsilon),\;\;\;x\;{\in}\;{\Omega}, \atop -{\Delta}_q{\upsilon}\;=\;{\mu}g(u),\;\;\;x\;{\in}\;{\Omega},} \atop u\;=\;\upsilon\;=\;0,\;\;\;x\;{\in}\;{\partial\Omega},}$$ where ${\Delta}_pu\;=\;div(|{\nabla}_u|^{p-2}{\nabla}_u)$, ${\Delta}_{q{\upsilon}}\;=\;div(|{\nabla}_{\upsilon}|^{q-2}{\nabla}_{\upsilon})$, p, $q\;{\geq}\;2$, $\Omega$ is a ball in $\mathbf{R}^N$ with a smooth boundary $\partial\Omega$, $N\;{\geq}\;1$, $\lambda$, $\mu$ are positive parameters, and f, g are smooth functions that are negative at the origin and f(x) ~ $x^m$ g(x) ~ $x^n$ for x large for some m, $n\;{\geq}\;0$ with mn < (p - 1)(q - 1). We establish the existence and uniqueness of positive radial solutions when the parameters $\lambda$ and $\mu$ are large.

POSITIVE RADIAL SOLUTIONS FOR A CLASS OF ELLIPTIC SYSTEMS CONCENTRATING ON SPHERES WITH POTENTIAL DECAY

  • Carriao, Paulo Cesar;Lisboa, Narciso Horta;Miyagaki, Olimpio Hiroshi
    • Bulletin of the Korean Mathematical Society
    • /
    • v.50 no.3
    • /
    • pp.839-865
    • /
    • 2013
  • We deal with the existence of positive radial solutions concentrating on spheres for the following class of elliptic system $$\large(S) \hfill{400} \{\array{-{\varepsilon}^2{\Delta}u+V_1(x)u=K(x)Q_u(u,v)\;in\;\mathbb{R}^N,\\-{\varepsilon}^2{\Delta}v+V_2(x)v=K(x)Q_v(u,v)\;in\;\mathbb{R}^N,\\u,v{\in}W^{1,2}(\mathbb{R}^N),\;u,v&gt;0\;in\;\mathbb{R}^N,}$$ where ${\varepsilon}$ is a small positive parameter; $V_1$, $V_2{\in}C^0(\mathbb{R}^N,[0,{\infty}))$ and $K{\in}C^0(\mathbb{R}^N,[0,{\infty}))$ are radially symmetric potentials; Q is a $(p+1)$-homogeneous function and p is subcritical, that is, 1 < $p$ < $2^*-1$, where $2^*=2N/(N-2)$ is the critical Sobolev exponent for $N{\geq}3$.