Qin W.,Civil Aviation Flight University of China
Journal of Coatings Technology Research | Year: 2011
The microstructure and corrosion behavior of electroless Ni-P alloy plating on 6061 aluminum alloys substrate in an alkaline plating bath with sodium hypophosphite as reducing agent were investigated. The effects of bath temperature on the plating rate, compositions, and microstructure of the electroless Ni-P deposits were studied. The results showed that the deposition rate and the P content of the electroless Ni-P deposits increased with the rise of the bath temperature. Scanning electron microscopy (SEM) of the deposits showed nodular structure for binary deposits. X-ray diffraction patterns of all the deposits revealed a single and broad peak which indicated the amorphous structure of the deposits. Corrosion resistance of the Ni-P coatings was evaluated by potentiodynamic polarization. The results indicated that electroless Ni-P plating could obviously improve the corrosion resistance of 6061 aluminum alloy. © 2010 ACA and OCCA.
Xu K.,Civil Aviation Flight University of China
Communications in Computer and Information Science | Year: 2012
A novel dual fuzzy neural network to civil aviation aircraft disturbance landing control is presented in this paper. Conventional automatic landing system (ALS) can provide a smooth landing, which is essential to the comfort of passengers. However, these systems work only within a specified operational safety envelope. When the conditions are beyond the envelope, such as turbulence or wind shear, they often cannot be used. The objective of this paper is to investigate the use of dual fuzzy neural network in ALS and to make that system more intelligent. Firstly the dual fuzzy neural network is trained from available flight data and then that trained neural network controls the landing, roll, pitch and altitude hold of the airplane. Current flight control law is adopted in the intelligent controller design. Tracking performance and robustness are demonstrated through software simulations. The neural network control has been implemented in MATLAB and the data for training have been taken from Flight Gear Simulator. Simulated results show that control for different flight phases is successful and the dual fuzzy neural network controllers provide the robustness to system parameter variation. © 2012 Springer-Verlag Berlin Heidelberg.
Xia Y.,Southwestern University of Finance and Economics |
Wang F.,Civil Aviation Flight University of China |
Deng W.-S.,Tamkang University
Information Sciences | Year: 2012
In a wireless sensor network, a fusion center may receive incorrect information from local sensors, with some probabilities of transmission errors, due to channel fading. To cope with such a problem, we generalize the likelihood-ratio-test method of Chen and Willett (2005)  and derive optimal local sensor compression rules that minimize the Bayesian cost under a given fusion rule and transmission error probabilities. Our proposed method is able to operate without conditional independence between sensor data, which is often required by existing methods. Numerical examples are also used to validate the performance through receiver operating characteristics curves. These examples highlight the interesting features of our method compared to those in ideal situations. © 2012 Elsevier Inc. All rights reserved.
Jiang L.,Civil Aviation Flight University of China
Procedia Engineering | Year: 2011
In consideration of the problem in traditional aero-engine fault diagnosis, a new algorithm was proposed, which does not rely on engine math model nor numerous data samples. This method based on grey relationship degree theory, engine gas path fault symptoms shifts were needed first, and then the relationship degree was calculated between ambiguous faults and specific faults to achieve the fault diagnosis. Finally, the CFM56-3 fault example validates the effectiveness and feasibility of this method. © 2011 Published by Elsevier Ltd.
Shu Y.,Civil Aviation Flight University of China
Modern Physics Letters B | Year: 2010
Using the complete discrimination system for polynomial method, we study the (2+1)-dimensional Davey-Stewartson equation and obtain the classifications of all its envelope traveling wave solutions. This is very convenient in practice to give the corresponding solutions for the concrete parameters. © 2010 World Scientific Publishing Company.