SWIR digital holography and imaging through smoke and flames: unveiling the invisible.

Since its inception, digital holography has been mainly carried out using visible light but soon various other regions of the electromagnetic spectrum has been fruitfully explored. The Short Wavelength Infrared (SWIR) region, despite its interesting peculiarities and appealing applications in the imaging field, has not yet been fully investigated in Digital Holography (DH). Here we present a compact and robust SWIR DH setup and demonstrate the peculiar and remarkable advantages offered by SWIR radiation for macroscopic object investigation.

A physical memristor based Muthuswamy-Chua-Ginoux system.

In 1976, Leon Chua showed that a thermistor can be modeled as a memristive device. Starting from this statement we designed a circuit that has four circuit elements: a linear passive inductor, a linear passive capacitor, a nonlinear resistor and a thermistor, that is, a nonlinear "locally active" memristor. Thus, the purpose of this work was to use a physical memristor, the thermistor, in a Muthuswamy-Chua chaotic system (circuit) instead of memristor emulators.

Delayed dynamics in an electronic relaxation oscillator.

We present an experimental investigation of the complex dynamics of a modulated relaxation oscillator implemented by using a unipolar junction transistor (UJT) showing the transition to chaos through torus breakdown. In a previous paper a continuous model was introduced for the same system, explaining chaos based on analogy with a memristor. We propose here a new approach based on a piecewise linear model with delay considering a measured parasitic delay effect.

Identification of minimal parameters for optimal suppression of chaos in dissipative driven systems.

Taming chaos arising from dissipative non-autonomous nonlinear systems by applying additional harmonic excitations is a reliable and widely used procedure nowadays. But the suppressory effectiveness of generic non-harmonic periodic excitations continues to be a significant challenge both to our theoretical understanding and in practical applications. Here we show how the effectiveness of generic suppressory excitations is optimally enhanced when the impulse transmitted by them (time integral over two consecutive zeros) is judiciously controlled in a not obvious way.