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An improved method for vehicle tracking in UAV-captured video is introduced in this paper, this method based on GPU (Graphics Processing Units) acceleration which have efficient parallel computing powers. Today, vehicle tracking in UAV videos has many meaningful applications in computer vision, such as traffic management and illegal vehicle tracking. However, the increased computational complexity...
The spatial filter is capable of splitting the original desired trajectory of the dual-stage actuator (DSA) into two segments with arbitrary range, controlled by a linear motor (LM) actuator and a piezoelectric actuator (PZT) microactuator, respectively. Backstepping nonsingular terminal sliding mode control law with error transformation is designed to allow the tracking error of the actuator to converge...
In this paper, interval type-2 fuzzy sets are used to analyze the operation of the extrusion mechanism of different 3D printers and the state of the wire-forming for 3D printer when different intervention strategies is selected. The discussion of the state for the extrusion mechanism of the 3D printer by using the theory of linguistic dynamic systems can simplify the description and deal with the...
This paper presents a systematic method on establishing a switched polytopic LPV model for the fight dynamics in high angle of attack maneuver. A conventional LPV system scheduled by angle of attack and roll rate is derived from the five-dof nonlinear dynamics of the aircraft based on the state transformation method. The LPV model is further transformed into the polytopic form though Tensor-Product...
In this paper, an output feedback control scheme is developed for the dynamic positioning (DP) system of vessels with immeasurable velocities. A high-gain observer is constructed to estimate the immeasurable velocities. By combining the high-gain observer with backstepping technique, an output feedback control scheme is designed. By Lyapunov functions, it is illustrated that the developed output feedback...
The problem of H∞ control for polytopic uncertain system with mixed delays is considered. Firstly, a new condition for the asymptotic stability of this system is deduced by employing a relaxed Lyapunov-Krasovskii functional and an accurate integral inequality. Secondly, by solving a set of linear matrix inequalities, a sufficient condition for the existence of a H∞ controller is adressed. Finally,...
WeChat is the largest acquaintance social networking platform in China, which has about 938 million monthly active user accounts. WeChat Moments, known as Friends Circle, serves social networking functions in which users can view information shared by friends. This paper addresses the problem of analyzing the patterns of cascading behavior in WeChat Moments. We obtain 229021 information cascades from...
Based on Computational Fluid Dynamics, ship's righting arms of different heeling angles were calculated to study ship's stability loss in following sea. First, based on the wave-generation method of defining inlet boundary conditions, the numerical wave tank was constructed for ship's movement in surf-riding. Second, one slender ship's flow filed in calm water was numerically simulated, and the righting...
This paper gives an disturbance observer-based attitude control method of a quadrotor Unmanned Aerial Vehicle (UAV) in the presence of large disturbance. Based on linear PID controller a disturbance observer is designed to estimate and compensate for the impact of internal/external disturbance simultaneously. After the disturbance observer is added, the attitude subsystem can overcome the strong coupling...
An adaptive dynamic surface control(DSC) strategy, combined with RBF neural network technology, is presented for the altitude subsystem of hypersonic flight vehicles. A performance function has been used, so that the altitude tracking error enters a pre-set range. Through the use of minimal learning techniques, the computational burden is drastically reduced. It has been proved that the closed-loop...
In the process of aircraft residual ice detection based on near infrared spectrum method, the qualities of the images, such as brightness and contrast, are easily influenced by sunlight, weather and other factors. Therefore, it is hard to precisely match the feature points. In this paper, an improved Harris local invariant feature matching method is proposed. The improved Harris feature point detection...
Adaptive beamforming plays an important role in smart antenna systems. Nonblind adaptive algorithm utilizes the known training sequence to update the weights of antenna array at the cost of low transmission efficiency. Without sending training sequences, blind adaptive algorithm is a solution to implement beamforming and increase the transmission efficiency. Two classic blind algorithms are studied,...
With the arrival of the era of “we media”, Community Question Answering(CQA) websites become a special “we media” platforms gradually. In this type of platforms, it has evolved as an interesting problem of discover the most authoritative answer provider in different fields because the number of authoritative answer providers is a key influential factor in a successful CQA system. Recently, there are...
In this paper, an adaptive fuzzy neural network control scheme is developed for a class of multiple-input and multiple-output (MIMO) nonlinear systems with uncertainties and state constraints. Fuzzy neural networks are used to approximate uncertainties in MIMO systems. Integral Lyapunov functions are introduced to address state constraints. By choosing an appropriate integral Lyapunov function, the...
A prescribed performance fuzzy adaptive decentralized control scheme is developed for a class of large-scale nonlinear systems with unknown control direction. The fuzzy systems are employed to approximate the unknown nonlinear functions, and the multiple Nussbaum-type functions are used to resolve the unknown control direction problem. By using the prescribed performance bounds, an adaptive fuzzy...
Different from current researches on Flickr group recommendation approaches that recommend groups to either users or images, this work proposes a unified framework that recommends groups to both users and images. Four types of entities in the Flickr system (users, tags, images, and groups) are integrated into a tetradic model, and then we uses tetradic decomposition to discover the latent semantic...
The POD propulsion ship is a new type of electric propulsion ship. Due to its special structure, the course control problem is complicated. The application of neural network in control field is more and more extensive. In this paper, based on POD ship's structure, MMG separated ship model has been established, and a CMAC-ADRC integrated controller is designed by combining the advantages of active...
Raman spectroscopy, which can provide valuable information about chemical structure, is widely used as an analytical tool for material identification and quantitative chemical/biological analysis. Surface-enhanced Raman spectroscopy (SERS), overcoming the traditional limitation of weak signals, improves the signal intensity significantly. The preprocessing of Raman spectrum is a very useful way to...
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