Meander system

Fig. 4. Direct tomographic, energy-dispersive X-ray diffraction imaging system. Suitcase enters device at left of Figure where spatial landmarks for registration purposes are measured by pre-scanner. In main housing centre-right of Figure, a primary cone-beam executes a meander scan, either of a region-of-interest or suitcase in its entirety. Illustration courtesy of GE Security, Germany.

According to the type of instrument in use the scanning point describes a sinusoidal-( flying-spot system), a zigzag- or a meander path on the plate. 

Fig. 2 Distribution of eogenetic carbonates and clay minerals in a meandering fluvial system under semi-arid climatic conditions.

For the moment, a coupling like (3.87) remains speculation. Only reaction-diffusion systems as studied in section 3.2 provide a modeling description which is based on reasonably first principles. The mathematically proper approach to autonomous meanders and relative Hopf bifurcation, which are present in the reaction-diffusion setting, would then be... 

C. Wulff. Theory of Meandering and Drifting Spiral Waves in Reaction-Diffusion Systems. PhD thesis, FU Berlin, 1996. 

The autonomous system with I t) = 0.06 has a steady state which is stable with respect to small perturbations. However, a supra-threshold perturbation, once locally applied, gives rise to a concentric wave propagating through the medium. Near to the center of the simulated domain a spiral wave rotating counterclockwise was created by a special choice of initial conditions. The spiral tip performed a compound rotation (meandering motion) including at least two different frequencies. The oscillation period measured far enough from the core center of unperturbed trajectory was... 

One-channel feedback has been first applied to control meandering spiral waves in experiments with the light-sensitive BZ medinm [21]. Later a theory of this control method has been elaborated for rigidly rotating [40, 43] and for meandering [30] spiral waves. In accordance with this control algorithm, the wave activity (e.g. the value of the variable v in Eq. (9.1)) is measured at a particular detection point as a function of time. This value oscillates with time and exceeds the value Ve every time instant ti, when a wave front touches the detector point. A short perturbation is applied to the system immediately at ti or after some time delay r, i.e. at instances = ti + r. The frequency of the periodic sequence of generated... 

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