Results 81 to 90 of about 12,799 (220)
Ultradiscrete Bifurcations for One Dimensional Dynamical Systems [PDF]
, 2020 Bifurcations of one dimensional dynamical systems are discussed based on some ultradiscrete equations. The ultradiscrete equations are derived from normal forms of one-dimensional nonlinear differential equations, each of which has saddle-node, transcritical, or supercritical pitchfork bifurcations.
arxiv +1 more source
“Assessing Predictability of Environmental Time Series With Statistical and Machine Learning Models”
Environmetrics, Volume 36, Issue 2, March 2025.ABSTRACT The relative merits of machine learning and statistical methods are discussed recently by Bonas et al. 2004, who raise important open questions for the statistical community regarding the value‐added benefits of data science and the future role of environmental statistics. Specifically, they identify three major knowledge gaps where statistics
Nathaniel K. Newlands +1 more
wiley +1 more source
Nonsmooth Homoclinic Bifurcation in a Conceptual Climate Model [PDF]
arXiv, 2016 Collision of equilibria with a splitting manifold has been locally studied, but might also be a contributing factor to global bifurcations. In particular a boundary collision can be coincident with collision of a virtual equilibrium with a periodic orbit, giving an analogue to a homoclinic bifurcation.
arxiv
The neodiapsid Thadeosaurus colcanapi from the upper Permian of Madagascar
Papers in Palaeontology, Volume 11, Issue 2, March/April 2025.Abstract The enigmatic neodiapsid Thadeosaurus colcanapi (Lower Sakamena Formation, southwestern Madagascar), sole species of the genus Thadeosaurus, is revised here. The attribution of 12 of the 21 referred specimens is confirmed, spanning all ontogenetic stages, and the anatomy of Thadeosaurus is redescribed in detail with comments on ontogenetical ...
Valentin Buffa +3 more
wiley +1 more source
Stability analysis for pitchfork bifurcations of solitary waves in generalized nonlinear Schroedinger equations [PDF]
, 2012 Linear stability of both sign-definite (positive) and sign-indefinite solitary waves near pitchfork bifurcations is analyzed for the generalized nonlinear Schroedinger equations with arbitrary forms of nonlinearity and external potentials in arbitrary spatial dimensions.
arxiv +1 more source
Earth and Space Science, Volume 12, Issue 3, March 2025.Abstract This study characterizes fluvial activity on Alba Mons using a combination of image and topographic data to inform photogeologic interpretation and hydrological modeling. We produced a comprehensive digital inventory of fluvial valleys that documents the extensive dendritic and parallel drainage patterns dissecting Early Amazonian volcanic ...
Stephen P. Scheidt +2 more
wiley +1 more source
EVALUATION OF VOLTAGE STABILITY DYNAMIC LOADING MARGIN CONSIDERING THE EFFECT OF LOAD MODELS, EXCITATION SYSTEM PARAMETERS AND REACTIVE POWER GENERATION LIMITS OF GENERATORS WITH A COMBINATION METHOD [PDF]
مجله مدل سازی در مهندسی, 2010 Nowadays, Voltage stability is an important types of power system stabilities. To analysis of voltage stability, different static and dynamic boundaries such as maximum Loadability point (MLP) and bifurcation points such as saddle node bifurcation (SNB),
نیما Amjady +1 more
doaj +1 more source
Mathematical Methods in the Applied Sciences, Volume 48, Issue 3, Page 2999-3021, February 2025.In this paper, we have formulated and analyzed a mathematical model with multiple time delays of the genetic regulatory network of the microRNA‐17‐92 (miR‐17‐92) cluster. We have focused on the effect of the associated transcriptional and translational time delays of both positive and negative feedback loops on the miR‐17‐92 regulatory network. To gain
Akshay Sharma +2 more
wiley +1 more source
Dynamics of a modified Leslie-Gower predator-prey model with double Allee effects
Mathematical Biosciences and EngineeringIn this paper, we investigate the dynamic behavior of a modified Leslie-Gower predator-prey model with the Allee effect on both prey and predator. It is shown that the model has at most two positive equilibria, where one is always a hyperbolic saddle and
Mengyun Xing, Mengxin He, Zhong Li
doaj +1 more source
Dynamics of a delay Schistosomiasis model in snail infections
Mathematical Biosciences and Engineering, 2011 In this paper we modify and study a system of delay differential equations model proposed by Nåsell and Hirsch (1973) for the transmission dynamics of schistosomiasis. The modified stochastic version of MacDonald’s model takes into account the time delay
Chunhua Shan, Hongjun Gao, Huaiping Zhu
doaj +1 more source