Seminar khoa hoc
9.00 AM – 10.00 AM: Dr. Nguyen Sy Dung trình bày về: "An Estimate of the Solution for A Class of Fractional-order Differential Inequality and Applying to Controlling Vibration"
Due to the complexly natural attributes of technical systems, reality has been shown that many systems could be modeled more precisely if they are modeled by using fractional calculus and fractionalorder differential equations. Inspired by this advantage, in this work a fractional-order derivative-based sliding mode controller (FD-SMC) for magnetorheological damper based on semi-active vehicle suspensions (MRD-SAVSs) is proposed to make the states of the given system asymptotically stable in the finite time. To show this assertion, a new estimate result for fractional differential inequality is presented to derive an FD-SMC law for the systems of MRD-SAVs. Then, this corresponding fractional-order sliding mode controller is designed to provide robustness, high performance control, finite time convergence in the presence of uncertainties and external disturbances.
10.00 AM - 11.00 AM: Dr. Nguyen Le Minh Tri trình bày: " Synthesis of g-C3N4/ graphene quantum dots hybrid photocatalyst "
The artificial photosynthesis using photocatalysts to convert CO 2 into useful solar fuels is a promising means of sustainable energy-oriented use. The search for suitable semiconductors as photocatalysts for CO 2 conversion using solar energy is a desirable target of material science. Recently, graphitic carbon nitrides (g-C 3 N 4 ), a metal-free photocatalyst, has received much attention for practical application of CO 2 photocatalytic reduction due to its features of low-cost, easy preparation process, good stability and suitable electronic structure. However, low adsorption of CO 2 , high recombination rate of photo-induced charge carriers and low light utilization result in low photocatalytic CO 2 performance. Herein, we reported a synthesis of a metal-free g-C 3 N 4 / graphene quantum dots hybrid photocatalyst for photocatalytic CO 2 reduction into solar fuels.