A scroll wave in a sufficiently thin layer of an excitable medium with negative filament tension can be stable nevertheless due to filament rigidity. Above a certain critical thickness of the medium, such a scroll wave will have a tendency to deform into a buckled, precessing state. Experimentally this will be seen as meandering of the spiral wave on the surface, the amplitude of which grows wi...

A systematic circuit design approach is proposed for experimental verification of hyperchaotic 2-, 3-, 4-scroll attractors from a generalized Matsumoto–Chua–Kobayashi (MCK) circuit. Moreover, using appropriate discrete and extended transformations, a novel digital signal processor (DSP) method is also presented for physically realizing the above hyperchaotic 2-, 3-, 4-scroll attractors. This is...

Here, I present the numerical computation of speed and direction of the drift of a spiral wave in an excitable medium in the presence of an electric field. The drift speed presents a strong variation close to the parameter value where the drift-speed component along the field direction from parallel becomes antiparallel. Using a simple phenomenological model and results from a numerical linear ...

Scroll rings are three-dimensional spiral waves of excitation that rotate around circular filaments. In a modified Belousov-Zhabotinsky reaction, these filaments expand, buckle, and build up gradients in rotation phase. The instability is caused by negative filament tension (-4.3x10;{-4}cm;{2}s) . Initial deformations are strongest in the direction normal to the filament's osculating plane, and...

Abstract. Consider a height two ideal, I, which is minimally generated by m homogeneous forms of degree d in the polynomial ring R = k[x, y]. Suppose that one column in the homogeneous presenting matrix φ of I has entries of degree n and all of the other entries of φ are linear. We identify an explicit generating set for the ideal A which defines the Rees algebra R = R[It]; so R = S/A for the p...

An investigation into the isolability of the location of intake and exhaust manifold leaks in heavy duty diesel engines is presented. In particular, established fault detection and isolation (FDI) methods are explored to assess their utility in successfully determining the location of a leak within the air path of an engine equipped with exhaust gas recirculation and an asymmetric twin-scroll t...

Recently, a scroll compressor for air conditioners has been developed, because of its high efficiency, quiet operation, light weight and small size. To accomplish high efficiency, self sealing mechanisms such as a tip seal and a swing link mechanism are very effective. Tip seals which are placed on the top of scroll wraps achieve thrust sealing and a swing link mechanism achieves radial sealing...