Invariance and polynomial design of strategies in the linear-quadratic game

A new algorithm to solve the H ^∞ control problem in the case of full information was presented. It combines the spectral and matrix methods. The polynomial Lur’e-Riccati operator was introduced. Parametrization of all solutions of the controlled plant equation by hidden variables was presented within the framework of the J.C. Willems behavioral approach. The kernel of the polynomial Lur’e-Riccati operator was decomposed into the direct sum of subspaces that are similar to the Jordan blocks. The saddle point of the linear-quadratic game which was found by V.A. Yakubovich in 1970 was shown to provide solution to the H ^∞ control problem for a considerable class of controlled plants.     

On the Protective Properties of Electrostatically Spraged Fluoroplastic and Epoxy Coatings

The protective and insulating properties of fluoroplastic and epoxy coatings applied by high-voltage electrostatic spraying were studied. The epoxy coatings were found to be less permeable than the fluoroplastic ones, yet they cannot be used to protect metal parts in corrosive environment because of their low chemical resistance.     

Stability of systems with several monotone nonlinearities

This paper is devoted to stability problems of automatic control systems. Frequency domain criteria for global asymptotic stability of equilibrium sets for new classes of nonlinearities are derived. Results are illustrated by examples.     

Memory leak detection in Plumbr

Platforms with automatic memory management, such as the JVM, are usually considered free of memory leaks. However, memory leaks can happen in such environments, as the garbage collector cannot free objects, which are not used by the application anymore, but are still referenced. Such unused objects can eventually fill up the heap and crash the application. Although this problem has been studied extensively, nevertheless, there are still many rooms for improvement in this area. This paper describes the statistical approach for memory leak detection, as an alternative, along with a commercial tool, Plumbr, which is based on the method. The tool is later analyzed with three case studies of real applications and in the process also analyzes strengths and weaknesses of the statistical approach for memory leak detection. Copyright © 2014 John Wiley & Sons, Ltd.     

Biosynthesis of zinc oxide nanoparticles by petals extract of Rosa indica L., its formulation as nail paint and evaluation of antifungal activity against fungi causing onychomycosis

Aim: The authors report the biological synthesis of zinc oxide nanoparticles (ZnO‐NPs) from the petals extract of Rosa indica L. (rose). Its efficacy was evaluated against two dermatophytes: namely: Trichophyton mentagrophytes and Microsporum canis which cause onychomycosis. The activity of antibiotics against the tested dermatophytes was enhanced, when evaluated in combination with ZnO‐NPs. Methods and results: The synthesised ZnO‐NPs were preliminary detected by using ultraviolet UV visible spectroscopy, which showed specific absorbance. The ZnO‐NPs were further characterised by nanoparticle tracking analysis (NTA), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), X‐ray diffraction and Zetasizer. Moreover, nanoparticles containing nail paint (nanopaint) was formulated and its antifungal activity was also assessed against T. mentagrophytes and M. canis. ZnO‐NPs and formulated nanopaint containing ZnO‐NPs, both showed significant antifungal activity. The maximum activity was noted against M. canis and lesser against T. mentagrophytes. Minimum inhibitory concentration of ZnO‐NPs was also determined against the dermatophytes causing onychomycosis infection. Conclusion: ZnO‐NPs can be utilised as a potential antifungal agent for the treatment of onychomycosis after more experimental trials.Inspec keywords: diseases, zinc compounds, nanoparticles, nanofabrication, antibacterial activity, microorganisms, nanomedicine, ultraviolet spectra, visible spectra, Fourier transform infrared spectra, transmission electron microscopy, X‐ray diffraction, biomedical materials, patient treatmentOther keywords: zinc oxide nanoparticle biosynthesis, Rosa indica L petals extract, nail paint, antifungal activity evaluation, dermatophyte, Trichophyton mentagrophytes, Microsporum canis, antibiotics activity, ultraviolet‐visible spectroscopy, nanoparticle tracking analysis, Fourier transform infrared spectroscopy, transmission electron microscopy, X‐ray diffraction, zetasizer, antifungal agent, onychomycosis treatment     

Stabilization of Oscillations in a Periodic System by Choosing Appropriate Couplings

We study a model containing coupled subsystems (MCCS) defined by a system of ordinary differential equations, where subsystems are systems of autonomous ordinary differential equations. The model splits into unrelated systems when the numerical parameter that characterizes couplings is ε = 0, and the couplings are given by time-periodic functions. We solve the natural stabilization problem which consists in finding relationships that simultaneously guarantee the existence and asymptotic stability of MCCS oscillations. We generalize results previously obtained for the case of two coupled subsystems each of which is defined on its own plane.     

Oscillation family in weakly coupled identical systems

Consideration was given to an autonomous model with weakly coupled identical subsystems. Existence of a family of periodic solutions which is similar to the family in a subsystem was established. A scenario of bifurcations of the characteristic exponents was given, and the stabilization problem was solved. An example was given.