83 citations · 260 across the 21 of their papers we have counts for
12 papers · 1 filter
Finite Invariant Sets with Bridging Points in Logistic IFS
Hibiki Kato, Tamotsu Onozaki, Yoshitaka Saiki +1
We investigate iterated function systems (IFS) that randomly alternate between two non-identical one-dimensional maps as simple models of regime-switching dynamical systems. Our pr…
The dynamics of the heterochaos baker maps
Yoshitaka Saiki, Hiroki Takahasi, Kenichiro Yamamoto +1
The heterochaos baker maps are piecewise affine maps of the unit square or cube introduced in [Nonlinearity 34, 2021, 5744--5761], to provide a hands-on, elementary understanding o…
Constructing low-dimensional ordinary differential equations from chaotic time series of high/infinite-dimensional systems using radial function-based regression
Natsuki Tsutsumi, Kengo Nakai, Yoshitaka Saiki
In our previous study (N. Tsutsumi, K. Nakai and Y. Saiki (2022)) we proposed a method of constructing a system of differential equations of chaotic behavior only from observable d…
Constructing differential equations using only a scalar time-series about continuous time chaotic dynamics
Natsuki Tsutsumi, Kengo Nakai, Yoshitaka Saiki
We propose a simple method of constructing a system of differential equations of chaotic behavior based on the regression only from a scalar observable time-series data. The estima…
The twisted baker map
Yoshitaka Saiki, Hiroki Takahasi, James A. Yorke
As a model to provide a hands-on, elementary understanding of "vortex dynamics", we introduce a piecewise linear non-invertible map called a twisted baker map. We show that the set…
Dynamical system analysis of a data-driven model constructed by reservoir computing
Miki U Kobayashi, Kengo Nakai, Yoshitaka Saiki +1
This study evaluates data-driven models from a dynamical system perspective, such as unstable fixed points, periodic orbits, chaotic saddle, Lyapunov exponents, manifold structures…
Hausdorff dimension of Cantor intersections and robust heterodimensional cycles for heterochaos horseshoe maps
Yoshitaka Saiki, Hiroki Takahasi, James A. Yorke
As a model to provide a hands-on, elementary understanding of chaotic dynamics in dimension three, we introduce a -open set of diffeomorphisms of having two hors…
Quasiperiodic orbits in Siegel disks/balls and the Babylonian problem
Yoshitaka Saiki, James A. Yorke
We investigate numerically complex dynamical systems where a fixed point is surrounded by a disk or ball of quasiperiodic orbits, where there is a change of variables (or conjugacy…
Piecewise-linear maps with heterogeneous chaos
Yoshitaka Saiki, Hiroki Takahasi, James A. Yorke
Chaotic dynamics can be quite heterogeneous in the sense that in some regions the dynamics are unstable in more directions than in other regions. When trajectories wander between t…
Solving the Babylonian Problem of quasiperiodic rotation rates
Suddhasattwa Das, Yoshitaka Saiki, Evelyn Sander +1
A trajectory is quasiperiodic if the trajectory lies on and is dense in some -dimensional torus, and there is a choice of coordinates on the…
Quantitative Quasiperiodicity
Suddhasattwa Das, Yoshitaka Saiki, Evelyn Sander +1
The Birkhoff Ergodic Theorem concludes that time averages, i.e., Birkhoff averages, of a function along a length ergodic trajectory of a fu…
Quantitative Quasiperiodicity
Suddhasattwa Das, Yoshitaka Saiki, Evelyn Sander +1
The Birkhoff Ergodic Theorem concludes that time averages, that is, Birkhoff averages, of a function along an ergodic trajectory of a function …