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We combine dual interval valued hesitant fuzzy sets with rough sets to construct a hybrid uncertainty theory. According to the proposed dual interval valued hesitant fuzzy relation, our paper firstly investigated the two rough approximation operators, lower and upper of dual interval valued hesitant fuzzy set. Properties of the two rough approximation operators, their relationships between three specific dual interval valued hesitant fuzzy sets as well as four special fuzzy relations, serial, reflexive, symmetric and transitive relations of the dual interval valued hesitant fuzzy are further studied. Finally, We show the proposed dual interval valued hesitant fuzzy rough set anastz can help making decisions in clinic medical diagnosis.

In this paper, the output feedback control problem for a genetic hypersonic vehicle is considered under the restriction that only the vehicle's velocity and altitude are measurable. High gain observers (HGO) are utilized to provide estimation signals for unmeasurable derivatives of the vehicle's velocity and altitude. A comprehensive stability analysis of the closed loop system under the output feedback control is carried to prove that the proposed control law yields semiglobal uniformly ultimately bounded tracking while keep all the closed loop signals bounded. Numerical simulation results are presented to validate the proposed control design.

This paper considers about the control problem for an underactuated quadrotor UAV system with model parameter uncertainty. Backstepping based techniques are utilized to design a nonlinear adaptive controller which can compensate for the mass uncertainty of the vehicle. Lyapunov based stability analysis shows that the proposed control design yields asymptotic tracking for the UAV's motion in x, y, z direction and the yaw rotation, while keep the stability of the closed loop dynamics of the quadrotor UAV. Numerical simulation results are provided to show the good tracking performance of proposed control laws.