Hu F.,Huizhou University
Computers and Fluids | Year: 2017
In this note, we try to improve the numerical resolution around the discontinuous region by simply modifying the original smoothness indicator in WENO-JS scheme . The purpose of this modification is to slightly increase the weight of less-smooth stencil. The procedure of modification only increases about 1% of CPU time compared with the classical WENO-JS scheme. And the modified scheme generates comparable numerical solutions with the WENO-M scheme  (which increases about 25% in CPU cost). © 2017 Elsevier Ltd
Cui H.,Huizhou University |
Peng W.,Huizhou University
Journal of Information Processing Systems | Year: 2017
Near-field source localization algorithms are very sensitive to sensor gain/phase response errors, and so it is important to calibrate the errors. We took into consideration the uniform linear array and are proposing a blind calibration algorithm that can estimate the directions-of-arrival and range parameters of incident signals and sensor gain/phase responses jointly, without the need for any reference source. They are estimated separately by using an iterative approach, but without the need for good initial guesses. The ambiguities in the estimations of 2-D electric angles and sensor gain/phase responses are also analyzed in this paper. We show that the ambiguities can be remedied by assuming that two sensor phase responses of the array have been previously calibrated. The behavior of the proposed method is illustrated through simulation experiments. The simulation results show that the convergent rate is fast and that the convergent precision is high. © 2017 KIPS.
Jiang H.,Renmin University of China |
Jiang H.,Huizhou University |
He W.,Fujian University of Technology
Expert Systems with Applications | Year: 2012
Support vector regression (SVR) has often been applied in the prediction of financial time series with many characteristics. On account of much time consumption of global SVR, local machines are carried out to accelerate the computation. In this paper, we introduce local grey SVR (LG-SVR) integrated grey relational grade with local SVR for financial time series forecasting. Pattern search method and leave-one-out errors are adopted for model selection. Experimental results of three real financial time series prediction demonstrate that LG-SVR can speed up computing speed and improve prediction accuracy. © 2011 Elsevier Ltd. All rights reserved.
Li H.,Huizhou University |
Liao J.,Huizhou University |
Zeng T.,Shanghai University of Electric Power
Catalysis Communications | Year: 2014
In this study, a new and facile solution-phase route to prepare CuO nanowires and nanorods with the assistance of salicylic acid was reported. Compared with the commercial CuO nanoparticles, both the CuO nanowires and nanorods exhibited significantly improved catalytic activity in the degradation of Rhodamine B with H2O2, which may result from their special one dimensional nanostructures. The apparent activation energy of Rhodamine B oxidation with H2O2 in the presence of the CuO nanowires and nanorods was 30.95 kJ·mol- 1 and 32.07 kJ·mol- 1, respectively, which was much lower than that in the absence of catalysts. © 2013 Elsevier B.V.
Chen G.,Huizhou University |
Yang Y.,Huizhou University |
Li J.,Xidian University
IET Control Theory and Applications | Year: 2012
This note considers the finite time stability of a class of hybrid dynamical systems, which has both switching and impulsive effect. First, by relaxing the restriction on Lyapunov function of the system, a new condition of finite time stability is given for non-linear systems. Then, this condition and the results of previous works (Bhat and Bernstein, 2000; Moulay and Perruquetti, 2003) are extended to study the finite time stability of a class of hybrid dynamical systems, several sufficient conditions are derived. Finally, a numerical example is given to illustrate the theoretical results. © 2011 The Institution of Engineering and Technology.
Liang J.,Huizhou University
Optics Letters | Year: 2010
The prediction is experimentally confirmed that bright spatial solitons can be formed in spontaneously selfdefocusing azo-doped polymers through a photoisomerization process, namely, angular hole burning. The experiments are actually the realization of a scheme of light-controlling light. Both linearly polarized and circularly polarized light can propagate as solitons in such media. The solitons with the same intensity but with different polarizations have different widths. The experimental results are further theoretically explained. © 2010 Optical Society of America.
Shi H.,Huizhou University
2012 IEEE International Conference on Information and Automation, ICIA 2012 | Year: 2012
An Anchor-optimized modified weighted centroid localization algorithm based on RSSI was proposed. Firstly, the algorithm optimize the anchor nodes according to the distance from the unknown node to the anchor nodes, and then it select the nearest four anchors to localize, the reciprocal of the sum of measured distance was be taken as the weigh. Finally the weights were modified so as to further improving the precision. Simulation results show that the algorithm accuracy has been significantly improved than the centroid algorithm and weighted centroid algorithm. © 2012 IEEE.
Guo P.,Huizhou University
Energy Procedia | Year: 2011
Today the internet provides, at modest cost, an unprecedented level of connectivity and the ability to communicate efficiently and effectively directly with customers. The emergence of the internet has led to the rapid growth of ebusiness, and this had an effect on the business of the tourism enterprises. One of the crucial issues in the e-business is to provide an appropriate level of quality of tourism service. E-business service providers strive to provide quality based services by investing significant amount of money and resources in the e-business technologies such as web design, user interfaces, advertisement, security and reliability, and web server performance. In this paper the research focuses on the performance of e-business for the application to the tourism enterprises. As is known to all, performance of the tourism enterprises plays a key role in the provision of quality-based services. A number of solutions have been proposed to improve the performance of e-business services for tourism consumers to purchase the tourism product and tourism service. © 2011 Published by Elsevier Ltd.
Chen G.,Huizhou University |
Yang Y.,Huizhou University
International Journal of Robust and Nonlinear Control | Year: 2014
This brief paper addresses the finite-time stability problem of switched positive linear systems. First, the concept of finite-time stability is extended to positive linear systems and switched positive linear systems. Then, by using the state transition matrix of the system and copositive Lyapunov function, we present a necessary and sufficient condition and a sufficient condition for finite-time stability of positive linear systems. Furthermore, two sufficient conditions for finite-time stability of switched positive linear systems are given by using the common copositive Lyapunov function and multiple copositive Lyapunov functions, a class of switching signals with average dwell time is designed to stabilize the system, and a computational method for vector functions used to construct the Lyapunov function of systems is proposed. Finally, a concrete application is provided to demonstrate the effectiveness of the proposed method. Copyright © 2012 John Wiley & Sons, Ltd.
Ying Y.,Huizhou University
Chaos (Woodbury, N.Y.) | Year: 2013
This paper considers the problem of finite time control for a class of time-varying unified chaotic system. First, based on the finite-time stability theory, a novel adaptive control technique is presented to achieve finite-time stabilization for time-varying unified chaotic system. Comparing with the existing methods, the proposed controller only need to be added on one state variable of systems and it is easy to be implemented. Then, a finite time control technique is provided to realize the tracking of any target function with second-order derivatives. Finally, Simulation results are provided to show the effectiveness of the proposed method.