Physical processes that control ENSO are relatively fast. For instance, it takes only several months for a Kelvin wave to cross the Pacific basin (Tk ’ 2 months), while Rossby waves travel the same distance in about half a year. Compared to such short time scales, the typical periodicity of El Niño is much longer (T ’ 2–7 yr). Thus, ENSO is fundamentally a low-frequency phenomenon in the contex...

A discrete Frenkel-Kontorova model with two alternate spring constants k1 and k2 is studied in detail. It is found that this model has a lots of surprising behaviors. The continuum version of this model is different from the sine-Gordon equation, which is the continuum version of the standard FK model. More interestingly, it has an unpinned commensurate phase which is translationally invariant ...

Plane time-harmonic waves with assigned wavelength are supposed to propagate in an infinite linear thermoelastic space: The thermodynamic response is framed into the time differential dual-phase-lag model, while Cowin–Nunziato theory used depict effect of porosity for elastic part. We able show that it possible identify two shear waves, undamped and not affected by and/or temperature, as well f...

We review some techniques employed in the studies of torques due to bodily tides, and explain why the MacDonald formula for the tidal torque is valid only in the zeroth order of the eccentricity divided by the quality factor, while its time-average is valid in the first order. As a result, the formula cannot be used for analysis in higher orders of e/Q . This necessitates some corrections in th...

In this note we investigate the spatial behavior of the solutions of the equation proposed to describe a theory for the heat conduction with two delay terms. We obtain an alternative of the Phragmén-Lindelöf type, which means that the solutions either decay or blow-up at infinity, both options in an exponential way. We also describe how to obtain an upper bound for the amplitude term. This is t...

This paper presents a three-phase 12-pulse phasecontrolled rectifier with unity displacement factor, low line current harmonic content, two quadrant operation and absence of phase shifting transformer. The circuit is composed by two three-phase 6-pulse rectifiers parallel connected by four balancing reactors. One is a conventional thyristor rectifier with a lag firing angle (a). The other is an...

When micro-organisms are in environments with multiple nutrients, they often preferentially utilise one first. A second is only utilised once the first is exhausted. Such a two-phase growth pattern is known as diauxic growth. Experimentally, this manifests itself through two distinct exponential growth phases separated by a lag phase of arrested growth. The duration of the lag phase can be quit...

Following the Smith compensator the parallel compensator designed for difficult, e.g. nonminimum phase plants is applied to systems with relay control. The compensator connected in parallel to the plant changes its properties so that the replacement plant model becomes simpler and may be shaped dependently upon the goal of the control. In the case of regulation on a constant level a first order...