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	Challenges and the way forward in China's new-type urbanization SCI/SSCI论文 OAI收割 2016 作者: Chen M. X.; Liu, W. D.; Lu, D. D. \| 收藏 \| 浏览/下载：20/0 \| 提交时间：2017/11/09 New-type urbanization Citizenization Land-centered urbanization People-oriented urbanization Challenges Way forward China rapid urbanization land-use policy
	Challenges and the way forward in China's new-type urbanization SCI/SSCI论文 OAI收割 2016 作者: Chen M. X.; Liu, W. D.; Lu, D. D. 收藏 \| 浏览/下载：27/0 \| 提交时间：2016/12/16 New-type urbanization Citizenization Land-centered urbanization People-oriented urbanization Challenges Way forward China rapid urbanization land-use policy
	Research on automatic multispectral images synthesis of space camera (EI CONFERENCE) 会议论文 OAI收割 Optoelectronic Imaging and Multimedia Technology, October 18, 2010 - October 20, 2010, Beijing, China 作者: Liu J.-G.; Wu X.-X.; Kong D.-Z.; Zhou H.-D. 收藏 \| 浏览/下载：17/0 \| 提交时间：2013/03/25 Multilinear CCD Sensor was often used on space cameras to obtain multispectral images with each line representing different band channels. However images of different band channels obtained at the same time didn't coincide as there were spaces between lines. Pixel numbers to be adjusted between images of different channels varied when the space camera worked by swaying forward and backward or adjusted row transfer period to compensate image movement. An automatic multispectral images synthesis algorithm of space camera was put forward on the basis of analysis of such phenomenon. In this algorithm a new evaluation function was used to determine pixel numbers to be adjusted and the image regions of each band channel to be clipped. In this way images of different band channels could be synthesized automatically to obtain an accurate colorful image. This algorithm can be used to dispose a large mount of images from space camera directly without any manual disposal so that efficiency could be improved remarkably. In validation experiments the automatic multispectral images synthesis algorithm was applied in synthesis of images obtained from outside scene experiment of a multispectral space camera. Result of validation experiments proved that the automatic multispectral images synthesis algorithm can realize accurate multispectral images synthesis of space camera and the efficiency can be improved markedly. 2010 SPIE.
	Research on high precision membrane mirror forming method (EI CONFERENCE) 会议论文 OAI收割 5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Large Mirrors and Telescopes, April 26, 2010 - April 29, 2010, Dalian, China Liu C.-Y.; Jia J.-Q.; Jin G.; Zhong X.; Gu S. 收藏 \| 浏览/下载：12/0 \| 提交时间：2013/03/25 With the development of aeromechanics large light reflector that satisfies the diffraction of light becomes the dominant object of the optical operator. The assumption of designing reflector with organic membrane with reflecting layer plated emerges as the times require. based on an analytical solution of Poisson's equation and careful analysis of forming method the paper puts forward a conclusion that multi-electrode controlled electrostatic stretching membrane mirror is a better way than single-electrode controlled electrostatic stretching membrane mirror and also gives a preliminary comparative analysis of these two method. 2010 Copyright SPIE - The International Society for Optical Engineering.
	Alignment of off-axis asphere and compensator with four poles (EI CONFERENCE) 会议论文 OAI收割 4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, November 19, 2008 - November 21, 2008, Chengdu, China 作者: Li J.; Chen Y.; Li J.; Li J.; Wang P. 收藏 \| 浏览/下载：58/0 \| 提交时间：2013/03/25 Aspheres are utilized widely thanks to the development of optical design manufacture and testing. Compensators are usually necessary when aspheres are under test. The alignment of aspheres and their compensators is a risk because it's tough to check whether the compensators work in right way. A new method of alignment with four poles is put forward in this paper. Optical interval error can be tight while it is quite important due to direct influence on central curvature conic constant and high order coefficients of aspherical surface. A modified on-axis Foucault apparatus is set up since it makes the optical axis visible and helps to control the error of off-axis amount. Some small holes are drilled in the metallic cell of the compensator so that the ends of poles can be stably relied on in order to increase operational repeatability. The method has been carried out practically and it matches the measurement result given by a set of theodolites. 2009 SPIE.
	A high-accuracy parameter estimation algorithm for jointless Frequency-shift track circuit (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 作者: Zheng X. 收藏 \| 浏览/下载：21/0 \| 提交时间：2013/03/25 FSK (Frequency Shift keying) signal which has advantages of narrow-bandwidth strong anti-interference ability long transmission distance and so on is used in jointless Frequency-shift track circuit to send different kinds of control signals. However as FSK is non-linearly modulated parameter estimation with high accuracy is hard to realize. Based on the spectrum analysis complement with time-frequency distribution a highaccuracy FSK signal parameter estimation algorithm is put forward in this paper. According to the signal characteristics under-sampling and ZFFT are used to improve the accuracy of spectrum analysis and the base frequency resolution meets system requirement of 0.02Hz. Wigner-Ville distribution has an excellent time-frequency concentration while serious cross-term interference at the same time. Through the design of kernel function the cross-terms are almost suppressed and the upper/down side frequency resolution meets the system requirement of 0.2Hz. The effectivities of all the methods mentioned above have been proved by MATLAB simulation which pave a solid way for the development of high-accuracy FSK signal parameter estimation devices. 2008 IEEE.
	All-solid-stated laser controller design based on digital optical feedback (EI CONFERENCE) 会议论文 OAI收割 Lasers in Material Processing and Manufacturing II, November 10, 2004 - November 12, 2004, Beijing, China 作者: Liu L.; Wang J.-L.; Wang J.-L.; Liu L. 收藏 \| 浏览/下载：26/0 \| 提交时间：2013/03/25 The new design about a CW digital all-solid-stated LD pumped Nd:YVO 4 controller is introduced. The stable output power of this digital laser controller which adopts Digital Signal Processor(TMS320C31) is approximately 20mW. The whole system is composed of constant- current source protection circuit pulse-width modulation circuit Si-photo-detector and amplified circuit and Digital Signal Processor control system etc. In terms of error deviation Based on nonlinear control curves of LD power output by Si-photo-detector the region control can be obtained by means of the PID control algorithm in the software platform that is error amendment and high stability laser power output can be achieved. And the precision of temperature control can reduce from 0.2C to 0.04C. By adopted integral separated mode PID control algorithm the LD output power instability ( %) down to 2%. By way of adopting the new digital design the work to protect the laser diode including the continuous adjustable output power with high accuracy and stability is easily obtained. The internal-external modulation control of the laser power based on digital optical feedback can be accomplished with stable power output. At last the bringing reasons of noise are analyzed and the solving methods are put forward in this paper.