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This paper presents a computational study of non-stoichiometric nickel oxide in a 64-cell NiO system to model and validate localized heating effects due to nanosecond laser irradiation. Variation in the Bandgap of NiO is studied as a function of varying concentrations of native defects, ranging from 0 to 25%. It is observed that there is a slight increase in the bandgap from 3.80eV for stoichiometric NiO to 3.86eV for Ni-rich NiO and to 3.95eV for O-rich NiO. It is hence deduced that the experimental laser irradiation leads to simultaneous reduction of Ni2+ ions and the oxidation of NiO as the number of laser pulses increase. As well, a detailed study on the effects of doping nickel family elements, i.e., palladium (Pd) and platinum (Pt), in stoichiometric NiO is presented. A bandgap decrease from 3.8eV for pure NiO to 2.5eV for Pd-doping and 2.0eV for Pt-doping for varying doping concentrations ranging from 0–25% Pd, Pt, respectively,is observed.

This paper considers the control of a polynomial variant of the original Chua's circuit. Both state space techniques and input-output techniques are presented. It is shown that standard control theory approaches can easily accommodate a chaotic system. Furthermore, it is shown that a harmonic balance approach could predict the period doubling phenomenon and onset of the double scroll chaos, as well as providing a control approach.

In this paper the control of a hyper2chaotic system is considered to show the role of system identification techniques in developing a model for effective control of highly complex systems. An indirect adaptive control scheme is considered and it is shown that simple prediction models which cannot possibly represent the dynamics of the chaotic system lead to stable control. Furthermore, it is shown that higher dimensional prediction models which more closely represent the chaotic process dynamics lead to controlled systems with sparse and disjoint basins of attraction for the desired steady state solution. The use of highly nonlinear models also results in a complex pattern of convergence to the desired state.

This paper presents a classical approach to controlling the Lorenz equations, a well known chaotic system. It is shown that proportional-plus-integral control using an easily measurable state variable gives both good stability and tracking properties well into the normally chaotic region. Here the input signal to the Lorenz equations is the applied heat via the Rayleigh number. This paper demonstrates that widely used classical control approaches can stabilize a chaotic system and have it track input signals in its usually chaotic regime.