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	MINIMALITY OF p-ADIC RATIONAL MAPS WITH GOOD REDUCTION 期刊论文 OAI收割 DISCRETE AND CONTINUOUS DYNAMICAL SYSTEMS, 2017, 卷号: 37, 期号: 6, 页码: 3161-3182 作者: Fan, Aihua; Fan, Shilei; Liao, Lingmin; Wang, Yuefei \| 收藏 \| 浏览/下载：14/0 \| 提交时间：2018/07/30 p-adic dynamical system minimal decomposition projective line good reduction rational map
	Research on model reference sliding mode control in roll stabilization of aerocraft (EI CONFERENCE) 会议论文 OAI收割 2011 International Conference on Electric Information and Control Engineering, ICEICE 2011, April 15, 2011 - April 17, 2011, Wuhan, China Chu H.-R. 收藏 \| 浏览/下载：39/0 \| 提交时间：2013/03/25 Aimed at aerospace roll stabilization control arithmetic based on model reference sliding mode variable structure theory and chattering reduction arithmetic are formulated. Correctness and validity of arithmetic are analyzed. With flight dynamics the roll-loop mathematic model and reference model are established. Sliding hyperplane is deduced based on model reference sliding mode variable structure theory. Combing with reaching law control law is derived and stability of roll-loop is analyzed. Chattering of aileron instructions is alleviate by using boundary layer approach. Digital flying simulation result shows that variable structure control arithmetic realized roll stabilization control the roll angle is less than 5.3 under powered flight and that of unpowered flight is less than 0.5 respectively. The command fin angle is less than 1.5. High frequency chattering of fin command nearby the minimum velocity was trailed off by chattering reduction arithmetic. The sliding mode control arithmetic show good performance when aerodynamic coefficients varies 20%. The control arithmetic is easy to be implemented for its simplicity. 2011 IEEE.
	Speech signal enhancement through wavelet domain MMSE filtering (EI CONFERENCE) 会议论文 OAI收割 2010 International Conference on Computer, Mechatronics, Control and Electronic Engineering, CMCE 2010, August 24, 2010 - August 26, 2010, Changchun, China Fenghua Z.; Le Y.; Jian W.; Qiang S. 收藏 \| 浏览/下载：24/0 \| 提交时间：2013/03/25 A new speech enhancement system that combine robust signal enhancement and minimum signal distortion is proposed in this paper. The proposed method introduces frequency depended parametric MMSE filtering techniques that involve wavelet packets. Voice activity detection (VAD) is used to further distinguish speech from noise and help to adaptively remove noise components from color noise eruptive noisy speech while perceptual criteria is also taken into account. Experimental results and objective quality measurement test results validate the proposed speech enhancement system and illustrate the benefit of the proposed wavelet domain MMSE filtering as an excellent speech enhancement method to provide sufficient noise reduction and good intelligibility and perceptual quality without causing considerable signal distortion and musical background noise method. 2010 IEEE.
	Analysis of spectrum narrowing of diode laser bar (EI CONFERENCE) 会议论文 OAI收割 Semiconductor Lasers and Applications III, November 12, 2007 - November 13, 2007, Beijing, China 作者: Liu Y.; Wang L.; Wang L.; Wang L.; Liu Y. 收藏 \| 浏览/下载：18/0 \| 提交时间：2013/03/25 Laser diode bar (LDB) are used increasingly often for many applications but spectral bandwidth of LDB are generally approximately 2-4nm far too wide for many demanding applications e.g. spin-exchange optical pumping terahertz generation and lidar. External-cavity feedback can improve the spectral properties of LD or LDB. However spectrum narrowing of LDB is more difficult than that of LD. Bar curvature (i.e. "smile") produced in the manufacturing process affects the spectrum narrowing greatly. By geometrical optics approach and ORIGIN software smile which can be corrected by plano-convex cylindrical lens is simulated and the result is in good agreement with experiment. The selection of grating which is also a critical factor of spectrum narrowing will be stated. Finally an external cavity consisting of fast axis collimator two plano-convex cylindrical lens and a diffraction grating is used. The scheme is implemented on a 19-element LDB and yields 3-fold reduction in spectral linewidth under the situation that all optical elements in the system which are not optimized. Further we use a slit in the experiment and analyze the spectrum narrowing of each element in LDB.