Gradient remediability in linear distributed parabolic systems analysis, approximations and simulations

The aim of this paper is the introduction of a new concept that concerned the analysis of a large class of distributed parabolic systems. It is the general concept of gradient remediability. More precisely, we study with respect to the gradient observation, the existence of an input operator (gradient efficient actuators) ensuring the compensation of known or unknown disturbances acting on the considered system. Then, we introduce and we characterize the notions of exact and weak gradient remediability and their relationship with the notions of exact and weak gradient controllability. Main properties concerning the notion of gradient efficient actuators are considered. The minimum energy problem is studies, and we show how to find the optimal control, which compensates the disturbance of the system. Approximations and numerical simulations are also presented.Keywords: actuators efficient; disturbance; gradient; parabolic systems; remediability; sensor

Regionally Gradient Efficient actuators and Sensors

In this paper, we introduce and characterize the notions of regional gradient remediability and regionally gradient efficient actuators. We study their relationship with regional gradient controllability and sensors. As an application, we consider the case where the domain is one and two dimension. nbs

Synthesis of vanadium oxides 5 wt.%VO 2 –M x O y by sol–gel process and application in cyclohexene epoxidation

International audienceA series of Si02, Al203 and TiO2 mixed vanadium materials have been prepared from inorganic precursors via the sol gel process and subsequently dried, calcined and reduced at elevated temperatures. Structural characterization of these materials was carried out by X-ray diffraction (XRD), N2 adsorption at 77K, thermal analysis (TGA/DTA), UV-vis diffused reflectance spectroscopy (DR UV-vis) and scanning electron microscopy (SEM) with energy dispersive X-ray (EDX). Their catalytic activities in the epoxidation of cyclohexene with TBHP as oxidant were also examined. Results of XRD and DR UV-visible diffused revealed that V02 species are predominant in all samples and no formation of V205 was detected. Experimental results indicated that the V02 Si02 catalysts performed excellently for the epoxidation of cyclohexene by tertiobutyl hydroperoxide