zbMATH — the first resource for mathematics

Geometry Search for the term Geometry in any field. Queries are case-independent.
Funct* Wildcard queries are specified by * (e.g. functions, functorial, etc.). Otherwise the search is exact.
"Topological group" Phrases (multi-words) should be set in "straight quotation marks".
au: Bourbaki & ti: Algebra Search for author and title. The and-operator & is default and can be omitted.
Chebyshev | Tschebyscheff The or-operator | allows to search for Chebyshev or Tschebyscheff.
"Quasi* map*" py: 1989 The resulting documents have publication year 1989.
so: Eur* J* Mat* Soc* cc: 14 Search for publications in a particular source with a Mathematics Subject Classification code (cc) in 14.
"Partial diff* eq*" ! elliptic The not-operator ! eliminates all results containing the word elliptic.
dt: b & au: Hilbert The document type is set to books; alternatively: j for journal articles, a for book articles.
py: 2000-2015 cc: (94A | 11T) Number ranges are accepted. Terms can be grouped within (parentheses).
la: chinese Find documents in a given language. ISO 639-1 language codes can also be used.

a & b logic and
a | b logic or
!ab logic not
abc* right wildcard
"ab c" phrase
(ab c) parentheses
any anywhere an internal document identifier
au author, editor ai internal author identifier
ti title la language
so source ab review, abstract
py publication year rv reviewer
cc MSC code ut uncontrolled term
dt document type (j: journal article; b: book; a: book article)
Bifurcation and stability analysis for a delayed Leslie-Gower predator-prey system. (English) Zbl 1201.34132
The authors study the following Leslie-Gower predator-prey system with time delay $$\aligned \dot x(t)&=r_1x(t)\left(1-\frac{x(t-\tau)}{K}\right)-mx(t)y(t),\\ \dot y(t)&=r_2y(t)\left(1-\frac{y(t-\tau)}{\gamma x(t)}\right), \endaligned\tag1$$ where $x(t)$ and $y(t)$ represent the densities of the prey and the predator populations, respectively. The parameters $r_1, r_2, m, K$ and $\gamma$ are positive constants, where $r_1$ and $r_2$ are the intrinsic growth rates of the prey and the predator, respectively, $K$ is the carrying capacity of the prey, $\gamma x$ stands for a prey-dependent carrying capacity of the predator, $m$ is the capturing rate of the predator. $\tau>0$ is a constant representing the feedback time delay of the prey and the predator species to their own growth. By analysing the characteristic equation, the local stability of the positive equilibrium of system (1) is addressed and the existence of Hopf bifurcations is established. It is shown that system (1) can exhibit an interesting property: under certain conditions, the positive equilibrium may switch a finite number of times between being stable and being unstable, but always becomes unstable eventually. By using the normal form theory and the center manifold theorem, the direction of Hopf bifurcations and the stability of bifurcating periodic solutions are determined. Using the global bifurcation theory for functional differential equations developed by {\it J. Wu} [Trans. Am. Math. Soc. 350, No. 12, 4799--4838 (1998; Zbl 0905.34034)], the global existence of periodic solutions of system (1) is established.

34K60Qualitative investigation and simulation of models
34K18Bifurcation theory of functional differential equations
34K13Periodic solutions of functional differential equations
92D25Population dynamics (general)
34K17Transformation and reduction of functional-differential equations and systems; normal forms
34K19Invariant manifolds (functional-differential equations)
Full Text: DOI