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	Academician Wen-Rui Hu - Eminent Pioneer and Prominent Leader of Microgravity Science in China 期刊论文 OAI收割 MICROGRAVITY SCIENCE AND TECHNOLOGY, 2, 2022, 卷号: 34, 页码: 19 作者: Li K(李凯); Zhao JF(赵建福); Kang Q(康琦); Wang SF(王双峰); Kang Q(康琦) \| 收藏 \| 浏览/下载：28/0 \| 提交时间：2022/10/23 Academician Wen-Rui Hu China Manned Space Program Microgravity research in China National Microgravity Laboratory Drop Tower Beijing Chinese recoverable satellite China Space Station Thermocapillary convection Volume ratio Gravity independence criteria of two-phase flow Taiji program in space gravitational wave physics
	The optical design of cubic phase plate testing system (EI CONFERENCE) 会议论文 OAI收割 2011 Symposium on Photonics and Optoelectronics, SOPO 2011, May 16, 2011 - May 18, 2011, Wuhan, China 作者: Zhang X.; Zhang X.; Zhang X.; Zhang Y. 收藏 \| 浏览/下载：19/0 \| 提交时间：2013/03/25 Computer-generated holograms (CGH) have been widely used for years in optical testing of aspheric surfaces in combination with Fizeau interferometers. With the development of diffraction optics computer technology and micro-processing technology the accuracy of the CGH testing can achieve a hundredth of a wave and the cost is reduced greatly. CGH is capable of producing an optical wavefront with any desired shape. So it is fascinating and will have good prospects to test free-form surfaces using CGH. As the CGH can create any wavefront shape it can also be used in unsymmetrical aspherical surfaces testing. Taking the cubic surface as an example this paper gives a method to test unsymmetrical surfaces. This paper gives the design to test a cubic surface. And the separation of the diffraction orders and the binary process of the continuous CGH phase function are discussed in detail. The alignment tolerance of the test system and the CGH fabrication tolerance are analyzed. We also present an idea using a CGH and two spherical lenses as null lens to test the cubic surface when the surface deviation is great. 2011 IEEE.
	Data processing method of multi-position strap-down north seeking system based on SVD (EI CONFERENCE) 会议论文 OAI收割 2011 International Conference on Mechatronic Science, Electric Engineering and Computer, MEC 2011, August 19, 2011 - August 22, 2011, Jilin, China Shen C.-W.; Liu C.; Yu S.-B.; Wang Z.-Q.; Li J.-R. 收藏 \| 浏览/下载：38/0 \| 提交时间：2013/03/25 With the aim to fit the sin wave curve of a multi-position strap-down north seeking system and to calculate the real north angle accurately the principles of the system and the algorithm of singular value decomposition(SVD) are introduced. The factors influencing the measuring precision are also analyzed. Then the algorithm is adopted to fit curves. Experimental results indicate that the singular value decomposition is very precise for its error sum is 1.1102V and the squared error is 2.8mV. Moreover for phase angle measurement measured six times in same direction the squared error is 24 (1). The method based on SVD can satisfy the system precision requirements of curve-fitting north seeking systems. 2011 IEEE.
	Design and image restoration research of a cubic-phase-plate system (EI CONFERENCE) 会议论文 OAI收割 5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies, April 26, 2010 - April 29, 2010, Dalian, China 作者: Zhang J.; Zhang J.; Zhang J.; Shi G.; Zhang X. 收藏 \| 浏览/下载：26/0 \| 提交时间：2013/03/25 Wave-front coding technology is a novel jointly optical and digital imaging technology which can greatly extend the depth of focus of optical systems. The image restoration process is an important part of wave-front coding technology. Using wave-front coding makes the modulation transfer function(MTF) values of the optical systems change little over a range of several times the depth of focus which means the system MTF is quite insensitive to defocus and there is no zero in the passband. So we can design a single filter for the restoration of images in different defocus positions. However it's hard to avoid noise during image acquisition and transmission processes. These noises will be amplified in the image restoration especially in the high frequency part when the MTF drop is relatively low. The restoration process significantly reduces the system signal to noise ratio this way. Aimed at the problem of noise amplification a new algorithm was proposed which incorporated wavelet denoising into the iterative steps of Lucy-Richardson algorithm. Better restoration results were obtained through the new algorithm effectively solving the noise amplification problem of original LR algorithm. Two sets of identical triplet imaging systems were designed in one of which the cubic-phase-plate was added. Imaging experiments of the manufactured systems were carried and the images of a traditional system and a wave-front coded system before and after decoding were compared. The results show that the designed wave-front coded system can extend the depth of focus by 40 times compared with the traditional system while maintaining the light flux and the image plane resolution. 2010 Copyright SPIE - The International Society for Optical Engineering.
	Graph fitting test method for the interpolation error of Moire fringe (EI CONFERENCE) 会议论文 OAI收割 9th International Conference on Electronic Measurement and Instruments, ICEMI 2009, August 16, 2009 - August 19, 2009, Beijing, China 作者: Sun Y.; Sun Y. 收藏 \| 浏览/下载：30/0 \| 提交时间：2013/03/25 In order to realize the fast test for the interpolation error the graph fitting test method for the interpolation error of Moire fringe is put forward in this paper. Firstly the triangular wave Moire fringe photoelectric signal of the encoder whose phase difference is 90 are sampled to get the Lissajous graph of the two signals. Secondly the single wave represented by the founded subsection function is used to fit the practical Moire fringe Lissajous graph. Then the fitting result is tested to verify whether it satisfies the accuracy requirement. Lastly the founded subsection function instead of the practical wave function is used to calculate the interpolation error. Using the graph fitting method to sample the Moire fringe single of 15-bits photoelectric encoder to get the interpolation error curve the tested maximum interpolation error is 70" and the minimum error is - 69". Comparing with the interpolation error which is received from traditional test method the change trend of the interpolation error curve is similar and peak-peak value is almost equality. The results of experiment indicate that: the equipment is convenient and the examination method is efficient and feasible. The measure speed is fast and the manifestation result is intuitionistic. The system can be used in the working field. The method can avoid the speed influence and realize the dynamic interpolation error measure which is significant for the research of encoder's dynamic accuracy characteristics. 2009 IEEE.
	Tunable ultraviolet laser source from a frequency doubled alexandrite laser (EI CONFERENCE) 会议论文 OAI收割 Optoelectronic Materials and Devices II, November 2, 2007 - November 5, 2007, Wuhan, China Shuhang L.; Jingjiao L.; Lijun W. 收藏 \| 浏览/下载：27/0 \| 提交时间：2013/03/25 A tunable ultraviolet laser source in the spectrum range of 0.36-0.388 m was obtained as second harmonics from a frequency doubled Alexandrite laser whose output covers the wave range over 0.72-0.78 m. A LBO crystal was used as frequency doubling crystal. The phase mateching angle in the wide spectrum range of the crystal was calculated and the crystal was cut in the way that the normal incidence at the center wavelength of the fundamental wave at the crystal. The output spectrum line was measured and the highest second harmonics conversion efficiency reached 1.2% from long pulse fundamental wave at the center wavelength.
	Low drive-voltage and high-bandwidth electro-optic modulators based on BaTiO3 thin-film waveguides (EI CONFERENCE) 会议论文 OAI收割 Science and Technology of Dielectrics for Active and Passive Photonic Devices - 210th Electrochemical Society Meeting, October 29, 2006 - November 3, 2006, Cancun, Mexico Sun D. G.; Fu X. H.; Liu Z. F.; Ho S. T.; Wessels B. W. 收藏 \| 浏览/下载：46/0 \| 提交时间：2013/03/25 We investigated electro-optic modulator structures to target low drive voltage high-speed modulation and small device size with c-axis grown BaTiO3/MgO ferro-electric thin films. In this study the calculations are focused on the ideal thin film with a quadratic relation between the half-wave drive voltage V and the interaction length L in the electro-optic modulation case we obtained in previous work. With the quadratic electro-optic modulating relation and the optimal rib waveguide structure of BaTiO3/MgO thin films the frequency-voltage-size performances for 2.5GHz 10GHz 40GHz and 100GHz modulation bandwidths have been obtained under half-wave drive voltages of 0.8V 1.6V 3.0V and 4.8V respectively for the ideal film with r51=730 pm/V at 1550nm wavelength where both the phase velocity matching condition and the conductor induced microwave attenuation are considered. The required device lengths to achieve these four typical values of modulation bandwidth are 3.3 mm 0.8 mm 0.4 mm and 0.2 mm respectively. With the c-axis grown BaTiO3/MgO crystal thin films and the quadratic electro-optic modulating relation an electro-optic coefficient of reff=180 pm/V for the c-axis grown BaTiO3/MgO ferro-electric thin films was measured which is relatively far from the ideal value of r51=560 pm/V. copyright The Electrochemical Society.
	Dynamical behavior in linearly coupled Oregonators 期刊论文 OAI收割 PHYSICA D, 2001, 卷号: 151, 期号: 2-4, 页码: 199-216 作者: Zhou, TS; Zhang, SC \| 收藏 \| 浏览/下载：15/0 \| 提交时间：2018/07/30 coupled oregonators single oscillator associate oscillator in-phase wave echo wave normal form