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	Adaptive flow optimization of a turbocharger compressor to improve engine low speed performance 期刊论文 OAI收割 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY, 2013, 卷号: 27, 期号: 6, 页码: 1581-1587 作者: Zhang, Yangjun; Wang, Chenfang; Zheng Xinqian; Zhuge, Weilin; Wu, Yulin 收藏 \| 浏览/下载：29/0 \| 提交时间：2015/10/27 Adaptive flow optimization Turbocharger Compressor Low speed performance Overall performance
	Applying observer feedback in motor control (EI CONFERENCE) 会议论文 OAI收割 3rd International Conference on Measuring Technology and Mechatronics Automation, ICMTMA 2011, January 6, 2011 - January 7, 2011, Shanghai, China Huan Z.-Y.; Li H.-W. 收藏 \| 浏览/下载：10/0 \| 提交时间：2013/03/25 When the speed is low or the encoder has a low precision speed measured by backward difference method has obvious truncation error. This will arise ripple in the control system speed response. Speed filtering can decrease the ripple but it's not good enough and it also induces lag. A speed feedback method based on all-state observer was introduced to improve the speed feedback performance. Experiment results show that compared to filtering method the control system performance is improved.
	Design of high-speed low-noise pre-amplifier for CCD camera (EI CONFERENCE) 会议论文 OAI收割 5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optoelectronic Materials and Devices for Detector, Imager, Display, and Energy Conversion Technology, April 26, 2010 - April 29, 2010, Dalian, China 作者: Zhang S. 收藏 \| 浏览/下载：30/0 \| 提交时间：2013/03/25 Pre-amplifier circuit is critical for the noise performance of the high speed CCD camera. Its main functions are amplification and impedance transform. The high speed and low noise pre-amplifier of CCD camera is discussed and designed in this paper. The high speed and low noise operational amplifier OPA842 is adopted as the main part. The gain-set resistors for the amplifier are designed optimally. The different precision gain-set resistors are swept using Monte Carlo method. CCD video signal which has high DC offset voltage is AC coupled to the amplifier. The output signal of the amplifier is source terminated using 50 ohms matching resistor so as to transmit the video signal through coaxial cable. When the circuit works in high speed the PCB will have important effect to circuit performance and can even cause the amplifier unstable due to the parasitic problem of PCB. So the parasitic model of the PCB is established and the PCB layout design issues are also presented. The design result shows that the pre-amplifier can be used in the camera whose pixel rate could be up to 40 MHz and its input referred noise density is about 3 nV/Hz 1/2. 2010 Copyright SPIE - The International Society for Optical Engineering.
	Application research of intelligent algorithm in electric-driven flight simulation turntable (EI CONFERENCE) 会议论文 OAI收割 ISECS International Colloquium on Computing, Communication, Control, and Management, CCCM 2008, August 3, 2008 - August 4, 2008, Guangzhou, China Xie M.-J.; Wang Z.-Q.; Wang L.-M. 收藏 \| 浏览/下载：39/0 \| 提交时间：2013/03/25 Application Research of Intelligent Algorithm in Electric-driven Flight Simulation Turntable is discussed in this paper. Fuzzy control is used to solve the problem of fast tracking and overshoot since its essence belongs to PD control In order to improve the performance of system in low speed a method named variance-gain adaptive algorithm is introduced in this paper. It defines the amplifier gain as a function whose independent variable is speed so the amplifier gain can automatically be adjusted with the change of speed. When the turntable runs at low speed it has a big amplifier gain a good rigidity and high tracking accuracy. When the turntable runs at high speed the method can control the amplifier gain and ensure the system dynamic performance. Design and implementation of these algorithms is introduced in detail. Experiment results show that the Flight Simulation Turntable has achieved the required performance through using fuzzy control algorithm and variance-gain adaptive algorithm. 2008 IEEE.
	High speed, low memory image coding using zero blocks of wavelet coefficients (EI CONFERENCE) 会议论文 OAI收割 4th International Conference on Image and Graphics, ICIG 2007, August 22, 2007 - August 24, 2007, Chengdu, China 作者: Zhang T.; Yang W.-G. 收藏 \| 浏览/下载：33/0 \| 提交时间：2013/03/25 We propose a new high speed low memory SPECK image coder based on the form of block-unit states called LBUS-SPECK which uses the form of block-unit states and the form of block exponents to substitute LIS and LSP of SPECK. A form of block-unit states is introduced to store the significance flag of coefficients and the value of the block-unit exponents. A form of block exponents is introduced to store the block exponents which are used to represent the max coefficient in a decomposed block. A new block depth-finding strategy is developed for searching insignificant sets at sorting stage. Experimental results show that the obtained PSNR values for the decoded images are very close to those of SPECK algorithm and the memory consumption is reduced by 9 times the encoding timing is saved about 15%. Comparing with SPECK algorithm this algorithm not only has better performance of the decoded images but also is easy to implement especially it provides an efficient way for hardware implementation of wavelet embedded block coding. 2007 IEEE.