中国科学院机构知识库网格系统: 检索

A new method for estimation of orthogonal and phase deviations of constant-envelope signals 期刊论文 OAI收割
Measurement Science and Technology, 2017, 卷号: 28, 期号: 12
作者: Li,Youyang; Lu,Xiaochun; Wang,Xue

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收藏 | 浏览/下载：21/0 | 提交时间：2021/11/29

constellation diagram Gauss mixture model EM algorithm orthogonal deviation phase deviation

Effect of graphite nanoparticles on CO2 hydrate phase equilibrium 期刊论文 OAI收割
fluid phase equilibria, 2016, 卷号: 414, 页码: 23-28
作者: Yu, Yi-song; Zhou, Shi-dong; Li, Xiao-sen; Wang, Shu-li

收藏 | 浏览/下载：12/0 | 提交时间：2016/12/05

Phase equilibrium Graphite nanoparticles Hydrate formation Thermodynamic model Average deviation

Influence of the Substrate Orientation on the Isothermal Solidification during TLP Bonding Single Crystal Superalloys 期刊论文 OAI收割
Journal of Materials Science & Technology, 2014, 卷号: 30, 期号: 3, 页码: 213-216
N. C. Sheng; B. Li; J. D. Liu; T. Jin; X. F. Sun; Z. Q. Hu

收藏 | 浏览/下载：20/0 | 提交时间：2014/04/18

Transient liquid phase (TLP) bonding Single crystal superalloys Orientation deviation Bonding time transient system

Error compensation of four and five buckets wavefront extraction algorithms in phase-shifting interferometer 期刊论文 OAI收割
OPTIK, 2013, 卷号: 124, 期号: 22, 页码: 5624-5627
作者: Zhu, Mingxin; Bai, Fuzhong; Gan, Shiming; Huang, Kaizheng; Huang, Linhai

收藏 | 浏览/下载：19/0 | 提交时间：2015/04/17

Phase-shifting algorithm Phase extraction Phase shift deviation Detector nonlinearity

Research on satellite platform vibration compensation technology for space optical communication (EI CONFERENCE) 会议论文 OAI收割
2012 International Meeting on Opto-Electronics Engineering and Materials Research, OEMR 2012, July 27, 2012 - July 29, 2012, Shenyang, Liaoning, China
Han C.; Li X.

收藏 | 浏览/下载：23/0 | 提交时间：2013/03/25

The piezo-electric steering control system is used to compensate the vibration of satellite platform. The mathematical model of piezo-electric steering system is built. The adaptive controller based on improved LMS filter algorithm is designed according to this system characteristic. The adaptive delay filter is designed to solve slow convergence speed problem of traditional algorithm. Meanwhile the adaptive delay filter can also compensate phase delay of control circuit. The adaptive deviation filter is introduced and it effectively compensates the vibration deviation which is low frequency and high amplitude. The experimental results show that the remained errors are rad which meets space optical communication requirement and proves that this control scheme is valid and feasible. (2012) Trans Tech Publications Switzerland.

An appraisal method of dynamic interpolation error for high precision encoder (EI CONFERENCE) 会议论文 OAI收割
2011 International Conference on Electronics and Optoelectronics, ICEOE 2011, July 29, 2011 - July 31, 2011, Dalian, China
作者: Wan Q.-H.; Liu C.-X.; Liu C.-X.

收藏 | 浏览/下载：29/0 | 提交时间：2013/03/25

This paper introduces an appraisal method of the dynamic interpolation error for the high precision encoder (Lissajou pattern calculation method). When the encoder is rolling two groups of fine photoelectric signals whose phase difference are /2 can be collected using data collected car. The shape and position deviation can be obtained through the comparison between Lissajou charts and the standard circle. Then dynamic interpolation error can be calculated out directly. This method is immune to the influence of encoder's speed and has no rigid demand to the test circumstances and test devices. The experimental results indicate that this method is feasible and important to the encoder's dynamic interpolation error checking. 2011 IEEE.

The aircraft autopilot design of parameters changing in a wide range (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
Zhen D.; Yue Z.

收藏 | 浏览/下载：29/0 | 提交时间：2013/03/25

Autopilot is an important part of aircraft Under the action of the disturbance torque for the flight parameters of aircraft Changing in a wide range the range was about 16km on the basic of analyzing the typical trajectory the max height was about 5100m the trajectory of feature points were selected the deviation of lateral was about 12m taking pitch control loop for example the maximum angle of attack was about 3.6 a sub- PID autopilot was designed using classical control theory the maximum elevator deflection was less than 5 using single-mode Transient suppression method the maximum aileron deflection was less than 2 the overload due to control surface transition deflection was avoided when control parameters changing the maximum roll was less than 5 the verification was done by non-linear simulation. The result showed that: the phase margin of autopilot was greater than 30 the response of overload can accurately track the given overload instruction. An autopilot design method of aircraft of parameter changes in a wide range was provided. 2011 IEEE. the bandwidth was more than 14rad / s the settling time was less than 0.7s the maximum overshoot was 23.3%

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：21/0 | 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.

Spatial distribution characteristics of geomagnetic Z component phase variation in Chinese mainland 期刊论文 OAI收割
CHINESE JOURNAL OF GEOPHYSICS-CHINESE EDITION, 2009, 卷号: 52, 期号: 4, 页码: 1033-1040
作者: Wang Ya-Li; Wu Ying-Yan; Lu Jun; Yu Su-Rong; Li Ming-Xiao

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收藏 | 浏览/下载：25/0 | 提交时间：2018/09/26

Phase variation Spatial distribution Geomagnetic "low-point" time Expected value Standard deviation

Method for recovering dynamic position of photoelectric encoder (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: Sun Y.; Liu Y.-S.; Liang L.-H.; Sun Y.; Wan Q.-H.

收藏 | 浏览/下载：20/0 | 提交时间：2013/03/25

This paper presents a method to recover dynamic position of photoelectric encoder. While working at dynamic state original outputs of the photoelectric encoder are in theory two sine or triangular signals with a phase difference of /2. However there are still deviations of actual output signals. Interpolating on the basis of this deviation signal will result in interpolation errors. In dynamic state true original signal data obtained by data acquisition system is a time equation. Through processing these data by data equiangular and harmonic analysis the equation will be converted from time domain to position domain and an original position equation can be formed. Then the interpolation errors also can be obtained. By this method the interpolation errors can be checked in dynamic state and it can also provide electric interpolation basis so that to improve dynamic interpolation precision of the encoder. Software simulation and experimental analysis all prove the method effective. This method is he basis in theory for precision checking and calibration in motion. 2009 SPIE.