Results 51 to 60 of about 13,830,771 (328)
The unpredictably eruptive dynamics of spruce budworm populations in eastern Canada
Population Ecology, EarlyView.We examine historical population data for spruce budworm from several locations through the period 1930–1997, and use density‐dependent recruitment curves to test whether the pattern of population growth over time is more consistent with Royama's (1984; Ecological Monographs 54:429–462) linear R(t) model of harmonic oscillation at Green River New ...
Barry J. Cooke, Jacques Régnière
wiley +1 more source
Global Behavior of Solutions to Two Classes of Second Order Rational Difference Equations [PDF]
, 2008 For nonnegative real numbers $\alpha$, $\beta$, $\gamma$, $A$, $B$ and $C$ such that $B+C>0$ and $\alpha+\beta+\gamma >0$, the difference equation \begin{equation*} x_{n+1}=\displaystyle\frac{\alpha +\beta x_{n}+\gamma x_{n-1}}{A+B x_{n}+C x_{n-1 ...
Basu, Sukanya, Merino, Orlando
core +3 more sources
Dynamic behavior of a second-order nonlinearrational difference equation
, 2015 This paper deals with the global attractivity of positive solutions of the second-order nonlinear difference equation \begin{equation*} x_{n+1}=\frac{ax_{n}^{k}+b\displaystyle\sum_{j=1}^{k-1}x_{n}^{j}x_{n-1}^{k-j}+cx_{n-1} ^{k}}{Ax_{n}^{k}+B\displaystyle\
Yacine Halim, N. Touafek, Y. Yazlık
semanticscholar +1 more source
Network topology drives population temporal variability in experimental habitat networks
Population Ecology, EarlyView.Habitat patches connected by dispersal pathways form habitat networks. We explored how network topology affects population outcomes in laboratory experiments using a model species (Daphnia carinata). Central habitat nodes in complex lattice networks exhibited lower temporal variability in population sizes, suggesting they support more stable ...
Yiwen Xu +3 more
wiley +1 more source
A Random Difference Equation with Dufresne Variables revisited [PDF]
, 2014 The Dufresne laws (laws of product of independent random variables with gamma and beta distributions) occur as stationary distribution of certain Markov chains $ X_n $ on $ R$ defined by: \begin{equation} X_n = A_n ( X_{n-1} + B_n ) \end{equation ...
Chamayou, Jean-François
core
Solvability of a class of hyperbolic-cosine-type difference equations
Advances in Difference Equations, 2020 We describe a method for constructing one of the basic classes of solvable hyperbolic-cosine-type difference equations, generalizing a known difference equation by Laplace in a natural way.
Stevo Stević +3 more
doaj +1 more source
occumb: An R package for site occupancy modeling of eDNA metabarcoding data
Population Ecology, EarlyView.This study introduces a new R package, occumb, for the convenient application of site occupancy modeling using environmental DNA (eDNA) metabarcoding data. We outline a data analysis workflow, including data setup, model fitting, model assessment, and comparison of potential study settings based on model predictions, all of which can be performed using
Keiichi Fukaya, Yuta Hasebe
wiley +1 more source
On an Exponential-Type Fuzzy Difference Equation
Advances in Difference Equations, 2010 Our goal is to investigate the existence of the positive solutions, the existence of a nonnegative equilibrium, and the convergence of a positive solution to a nonnegative equilibrium of the fuzzy difference equation , , , where and the initial values
Stefanidou G +2 more
doaj +2 more sources
Difference equation for a population model
Discrete Dynamics in Nature and Society, 2000 In this paper we consider a difference equation of the form u(t+2)=αu(t+1)+βu(t+1)−αu(t)αu(t), for t>−∞, seems to be a general statement of a relative socio-spatial dynamics. Indeed this equation is one of “population model”.
Mami Suzuki
doaj +1 more source
Electronic Journal of Qualitative Theory of Differential Equations, 2014 Well-defined solutions of the bilinear difference equation are represented in terms of generalized Fibonacci sequences and the initial value. Our results extend and give natural explanations of some recent results in the literature.
Stevo Stevic
doaj +1 more source