Various clustering methods have been applied to climate, ecological, and other environmental datasets, for example to define climate zones, automate land-use classification, and similar tasks. Measuring the “goodness” of such clusters is generally application-dependent and highly subjective, often requiring domain expertise and/or validation with field data (which can be costly or even impossib...

OBJECTIVE Synchronization between distributed rhythms in the brain is commonly assessed by estimating the synchronization strength from simultaneous measurements. This approach, however, does not elucidate the phase dynamics that underlies synchronization. For this, an explicit dynamical model is required. Based on the assumption that the recorded rhythms can be described as weakly coupled osci...

Isolated invariant sets and their associated Conley indices are valuable tools for studying dynamical systems and their global invariant structures. Through their design, they aim to capture invariant behavior which is robust under small perturbations, and this in turn makes them amenable to a computational treatment. Over the years, a number of algorithms have been proposed to find index pairs...

Dynamical zeta functions are an important tool to quantize chaotic dynamical systems. The basic quantization rules require the computation of the zeta functions on the real energy axis, where their Euler product representations running over the classical periodic orbits usually do not converge due to the existence of the so–called entropy barrier determined by the topological entropy of the cla...

In this study, we aimed to systematically and globally evaluate the monthly precipitation forecasts of JMA/MRI-CPS2, a dynamical seasonal climate forecast (Dyn-SCF) system operated by Japan Meteorological Agency, comparing its with those statistical SCF (St-SCF) using indices. We developed new global St-SCF 17 indices compared JMA/MRI-CPS2. Consequently, skill JMA/MRI-CPS2 was determined be hig...

Abstract. Recent advances in visual data analysis are well suited to gain insights into dynamical processes the atmosphere. We apply novel methods for three-dimensional (3-D) interactive investigate marine cold air outbreaks (MCAOs) and polar lows (PLs) recently released ERA5 reanalysis data. Our study aims at revealing 3-D perspectives on MCAOs PLs improving diagnostic indices capture these we...

in this paper, we introduce a notion of property (t) for a c∗-dynamical system (a, g, α) consisting of a unital c∗-algebra a,a locally compact group g, and an action α on a. as a result,we show that if a has strong property (t) and g has kazhdan’sproperty (t), then the triple (a, g, α) has property (t).

we establish a relationship between general constrained pseudoconvex optimization problems and globally projected dynamical systems. a corresponding novel neural network model, which is globally convergent and stable in the sense of lyapunov, is proposed. both theoretical and numerical approaches are considered. numerical simulations for three constrained nonlinear optimization problems are giv...

in this paper, we introduce the concept of dynamical distance on a nuclear con-guration space. we partition the nuclear conguration space into disjoint classes. this clas-sication coincides with the classical partitioning of molecular systems via the concept ofconjugacy of dynamical systems. it gives a quantitative criterion to distinguish dierentmolecular structures.

In this paper, we consider systems of vectors in a Hilbert space \(\mathcal {H}\) the form \(\{g_{jk}: j \in J, \, k\in K\}\subseteq \mathcal {H}\), where J and K are countable sets indices. We find conditions under which local reconstruction properties such system extend to global stable recovery on whole space. As particular case, obtain new local-to-global results for type \(\{A^ng\}_{g\in {...