Gao Ji-Hua

Phase Space Compression in One-Dimensional Complex Ginzburg–Landau Equation

The transition from stationary to oscillatory states in dynamical systems under phase space compression is investigated. By considering the model for the spatially one-dimensional complex Ginzburg–Landau equation, we find that defect turbulence can be substituted with stationary and oscillatory signals by applying system perturbation and confining variable into various ranges. The transition procedure described by the oscillatory frequency is studied via numerical simulations in detail.

Synchronizing spiral waves in a coupled Rössler system

The synchronisation of spiral patterns in a drive-response Rossler system is studied. The existence of three types of synchronisation is revealed by inspecting the coupling parameter space. Two transient stages of phase synchronisation and partial synchronisation are observed in a comparatively weak feedback coupling parameter regime, whilst complete synchronisation of spirals is found with strong negative couplings. Detailed observations of the synchronous process, such as oscillatory frequencies, parameters mismatches and amplitude variations, etc, are investigated via numerical simulations.

Controlling Spatiotemporal Chaos with a Generalized Feedback Method

The usual linear variable feedback control method is extended to a generalized function feedback scheme. The scheme is applied to high-dimensional spatiotemporal systems. By a combination of local generalized feedback control and the spatial coupling effect among elements, turbulent motion can be successfully eliminated.

Size transition of spiral waves using the pulse array method

The domain size of spiral waves is an important issue in studies of two-dimensional (2D) spatiotemporal patterns. In this work, we use the 2D complex Ginzburg–Landau equation (CGLE) as our model and find that an initially big spiral can successfully transfer to several small spirals by applying a pulse array method. The impacts of several important factors, such as array density, controlling intensity and pulsing time, are investigated. This control approach may be useful for the control of 2D spatiotemporal patterns and has potential applications in the control of some realistic systems, such as meteorological and cardiac systems.

Controlling spatiotemporal chaos by speed feedback method

The usual linear variable feedback control method is extended to the speed feedback approach in the study of controlling spatiotemporal chaos in the one-dimensional complex Ginzburg-Landau equation. The controllabilities in diverse systems with different sizes and target periodic states are investigated by theoretical analysis and numerical simulation.

Synchronization of Spatiotemporal Chaos in Coupled Complex Ginzburg Landau Oscillators

Synchronization of spatiotemporal distributed system is investigated by considering the model of 1D diffusively coupled complex Ginzburg–Landau oscillators. An itinerant approach is suggested to randomly move turbulent signal injections in the space of spatiotemporal chaos. Our numerical simulations show that perfect turbulence synchronization can be achieved with properly selected itinerant time and coupling intensity.

Controlling Chaos with Rectificative Feedback Injections in 2D Coupled Complex Ginzburg-Landau Oscillators

A model of two-dimensional coupled complex Ginzburg-Landau oscillators driven by a rectificative feedback controller is used to study controlling spatiotemporal chaos without gradient force items. By properly selecting the signal injecting position with considering the maximum gap between signals and targets, and adjusting the control time interval, we have finally obtained the efficient chaos control via numerical simulations.