Results 41 to 50 of about 13,731,074 (335)
Positive solutions of Schrödinger-Kirchhoff-Poisson system without compact condition
Boundary Value Problems, 2017 Purpose The existence of positive solutions for a class of nonlinear Schrödinger-Kirchhoff-Poisson systems. Methods Variational method. Results Some results on the existence of positive solutions.
Fengxia Liu, Shuli Wang
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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
, 2016 By means of the method of upper and lower solutions together with the Schauder fixed point theorem, the conditions for the existence of at least one positive solution are established for some higher-order singular infinite-point fractional differential ...
Qi Zhong, Xingqiu Zhang
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Advances in Differential Equations, 2015 In this paper, we discuss the existence of positive solution to singular fractional differential equations involving Caputo fractional derivative. Necessary and sufficient condition for the existence of C2[0,1]\documentclass[12pt]{minimal} \usepackage ...
Yongqing Wang, Lishan Liu
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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
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Mathematical Modelling and Analysis, 2014 In this article, the existence of multiple positive solutions of boundary-value problems for nonlinear singular fractional order elastic beam equations is established.
Yuji Liu
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Two nonnegative solutions for two-dimensional nonlinear wave equations
Cubo, 2022 We study a class of initial value problems for two-dimensional nonlinear wave equations. A new topological approach is applied to prove the existence of at least two nonnegative classical solutions.
Svetlin Georgiev, Mohamed Majdoub
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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
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Positive solutions for phi-Laplace equations with discontinuous state-dependent forcing terms
Nonlinear Analysis, 2019 This paper concerns the existence, localization and multiplicity of positive solutions for a φ-Laplacian problem with a perturbed term that may have discontinuities in the state variable. First, the initial discontinuous differential equation is replaced
Radu Precup, Jorge Rodríguez-López
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Positive solutions of an obstacle problem [PDF]
Annales de la faculté des sciences de Toulouse Mathématiques, 1995 In this paper the author studies the existence of positive solutions of the obstacle problem, with a nonlinear term in the variational inequality. The variational problem is formulated in an exterior domain with a smooth boundary. A positive parameter \(\lambda\) is included in the variational inequality and a discussion is done according to the values
openaire +2 more sources