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A WAcrobot is an underactuated nonlinear system that has three degrees of freedom (DOF) and two inputs. This paper discusses the global stabilization control problem for this 3-DOF underactuated system. A new control strategy is developed to solve this problem. The strategy first changes the 3-DOF WAcrobot system to be a 2-DOF reduced-order model in finite time. This transforms the stabilizing control of the WAcrobot system into that of the reduced-order model. After that, nonsingular control laws that globally stabilize the reduced-order model at the origin are designed. It guarantees the stabilizing control objective of the WAcrobot to be achieved. Finally, a simulation experimental example demonstrates the validity of the presented theoretical results. Simulation results show the advantage of our strategy over others. [ABSTRACT FROM AUTHOR]

An underactuated wheeled inverted pendulum (UWIP) is a nonlinear mechanical system that has two degrees of freedom and has only one control input. The motion planning problem for this nonlinear system is difficult to solve because of the existence of an uncontrollable manifold in the configuration space. In this paper, we present a method of designing motion trajectory for this underactuated system. The design of trajectory is based on the dynamic properties of the UWIP system. Furthermore, the tracking control of the UWIP for the constructed trajectory is also studied. A tracking control law is designed by using quadratic optimal control theory. Numerical simulation results verify the effectiveness of the presented theoretical results. [ABSTRACT FROM AUTHOR]

We study the properties of the Triebel-Lizorkin spaces associated with the multidimensional Hermite expansions on Rd (d≥1). In addition to the endpoint estimates, we give the continuous characterizations of these spaces via harmonic and thermic extensions from Rd into R+d+1. Based on this result, we obtain the boundedness of Riesz transform associated with the Hermite expansions. [ABSTRACT FROM AUTHOR]

Aiming at tracking maneuvering target of surface movement radar (SMR) for the advanced surface movement guidance and control system (A-SMGCS), the variable structure interacting multiple model (VS-IMM) algorithm is used in the system. Firstly, according to the real movement of aircraft, a constant velocity motion model is established, as well as a constant acceleration motion model and a constant turn motion model. Then, considering the defects of the fixed structure interacting multiple model (FS-IMM) algorithm, the VS-IMM algorithm is applied to the airport surface movement target tracking by combining with the airport map. Finally, VS-IMM and FS-IMM algorithms are designed by extended Kalman filtering (EKF), and they are compared through computer simulation. Simulation results show that VS-IMM algorithm is more reliable than IMM algorithm on tracking accuracy. So VS-IMM algorithm has the greater value on surface maneuvering target tracking. [ABSTRACT FROM AUTHOR]

This paper presents a weighted L estimate with power weights for the maximal operator of commutators generated by compactly supported multipliers and Lipschitz functions. As an application, we study the almost convergence of the commutators, which is generated by the Bochner-Riesz means under the critical index and Lipschitz functions, for functions in L ( p ⩾ 2). [ABSTRACT FROM AUTHOR]

A spring-coupled three-link horizontal manipulator (STHM) is an underactuated mechanical system that possesses two control inputs and three degrees of freedom (DOF). This paper discusses the stabilization control problem for this multi-DOF underactuated system. By using an energy-absorbing idea, we design two types of virtual friction controllers: PsD controller and PD controller. Additionally, the stability of the control system is analyzed based on Lyapunov theory and LaSalle's invariance principle. The design of the stabilizing controller in this paper makes good use of the physical characteristics of the STHM system. The design process of the whole control system is simple. Numerical examples demonstrate the validity and superiority of our developed control strategy. [ABSTRACT FROM AUTHOR]

Four-dimensional (4D) trajectory is considered to be one of the effective means to reduce the environmental impact of aviation while increasing capacity and safety. This paper proposes an approach to optimize cruise speed profile subject to wind uncertainty, aiming to reduce the fuel burn complying with the Required Time of Arrival (RTA) constraints. The approach is based on a probabilistic framework, and the uncertainty propagation is analyzed using a Probability Transformation Method, and the probability distributions of arrival time and fuel consumption are determined. In addition, from an airborne operation perspective, transition profiles need to be considered in the reference speed optimization problem, aiming to improve the rationale of the reference trajectory. Numerical simulations are presented, and the results demonstrate that the speed profiles optimized by this method are able to meet the RTA constraints in the presence of wind uncertainty, with an average reduction of 7.04% in fuel consumption compared with that of the flight data. [ABSTRACT FROM AUTHOR]

At present, airlines cannot meet the requirements of increasing air cargo volume and cargo service quality by simply improving air transportation capacity. On the basis of increasing the construction of aviation logistics distribution centers, airlines also need to optimize the distribution route. By analyzing and comparing the application of genetic algorithm in the problem of distribution path optimization, this paper proposes a new adaptive genetic algorithm with adaptive mutation to improve the search ability in the local range, which has faster convergence speed than the general genetic algorithm. And solve the logistics node location model. The result proves that the algorithm is faster and more accurate, and can solve the transportation path problem in distribution. [ABSTRACT FROM AUTHOR]