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	The effect of relative measured position on zircon SIMS U-Pb dating 期刊论文 OAI收割 ACTA PETROLOGICA SINICA, 2019, 卷号: 35, 期号: 8, 页码: 2615-+ 作者: Ling XiaoXiao; Li QiuLi; Liu Yu; Tang GuoQiang; Li Jiao \| 收藏 \| 浏览/下载：35/0 \| 提交时间：2019/12/04 SIMS Zircon U-Pb Age Measured position System bias
	Data normalization of single camera visual measurement network system (EI CONFERENCE) 会议论文 OAI收割 2012 International Conference on Information Technology and Management Innovation, ICITMI 2012, November 10, 2012 - November 11, 2012, Guangzhou, China 作者: Zhang Y.-C.; Zhou J. 收藏 \| 浏览/下载：22/0 \| 提交时间：2013/03/25 With the development of visual measurement system Normalize the measured coordinates into the same world coordinate system Apply in the three coordinate measuring machine(CMM) to have the simulation experiment So the data normalization has the advantage of more high precision. (2013) Trans Tech Publications the visual measurement system of single camera which applied in the imaging theory of optical feature points then get the global data the result indicates that the maximum absolute tolerance between the normalization coordinates via the center of point set and the ones measured by CMM directly is 0.058mm Switzerland. it has been widespread used in the modern production. Due to the limit of the environment in scene and achieve the overall measurement the visual measurement system of single camera could not measure the shield between the measured objects each other. Focus on this problem But the one between the coordinate repeatedly measured at the position of one network control point is 0.066mm present a kind of the the knowledge of measurement network based on the visual measurement of single camera set up the measurement network system via the multi-control points. Measure the optical feature points in every network control point via the visual measurement system of single camera
	Design of motion compensation mechanism of satellite remote sensing camera (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2011: Space Exploration Technologies and Applications, May 24, 2011 - May 26, 2011, Beijing, China Gu S.; Yan Y.; Xu K.; Jin G. 收藏 \| 浏览/下载：47/0 \| 提交时间：2013/03/25 With the development of aerospace remote sensing technology the ground resolution of remote sensing camera enhances continuously. Since there is relative motion between camera and ground target when taking pictures the target image recorded in recording media is moved and blurred. In order to enhance the imaging quality and resolution of the camera the image motion had to be compensated. In order to abate the effect of image motion to image quality of space camera and improve the resolution of the camera the compensation method of image motion to space camera is researched. First the reason of producing drift angle and adjustment principle are analyzed in this paper. This paper introduce the composition and transmission principle of image motion compensation mechanism. Second the system adopts 80C31 as controller of drift angle and adopts stepping motor for actuators and adopts absolute photoelectric encoder as the drift Angle measuring element. Then the control mathematical model of the image motion compensation mechanism are deduced and it achieve the closed-loop control of the drift angle position. At the last this paper analyses the transmission precision of the mechanism. Through the experiment we measured the actual precision of the image motion compensation mechanism and compared with the theoretical analysis. There are two major contributions in this paper. First the traditional image motion compensation mechanism is big volume and quality heavy. This has not fit for the development trend of space camera miniaturization and lightweight. But if reduce the volume and quality of mechanism it will bring adverse effects for the precision and stiffness of mechanism. For this problem This paper designed a image motion compensation that have some advantages such as small size light weight at the same time high precision stiffness and so on. This image motion compensation can be applicable to the small optics cameras with high resolution. Second the traditional mechanism control need to corrected fitting and iterative for the control formula of mechanism. Only in this way we can get the optimal control mathematical model. This paper has high precision of the control formula derived. It can achieve the high precision control without fitting It also simplify the difficulty of control mathematical model establishment. This paper designed the range of adjusting of image motion compensation mechanism between -5 +5. Based on choosing-5 -4 -3 -2 -1 0 +1 +2 +3 +4 +4 as the expectation value of the imaginary drift angle we get ten groups of the fact data in adjusting drift angle measured. The test results show that the precision of the drift angle control system can be achieved in 1. It can meet the system requirements that the precision of the control system is less than 3' and it can achieve the high-precision image motion compensation. 2011 SPIE.
	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：34/0 \| 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.
	Research of error correction of LEO satellite orbit prediction for vehicle-borne tracking and position device (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 作者: Wang J.-J.; Guo L.-H. 收藏 \| 浏览/下载：27/0 \| 提交时间：2013/03/25 Vehicle-borne tracking and position device is used to track LEO satellite. Because of the absence of the target which might be caused by cloud or zenith blind zone the forecasting data will be used to acquire the target. While orbit prediction has serious errors the target is always missed. Meanwhile in its application to the vehicle-borne tracking and position device due to the base of instability in the tracking process it will result in significant difference between predicting data and tracking data so the target will be not tracked rapidly. We applied tracking data to predict satellite orbits by improving Laplace method and then corrected the error between Predicted data and actual measured data by interpolation method of Lagrange which improves the accuracy of prediction values. The testing data shows the accuracy of predicted data ranging from 3' to 10" for both azimuth and elevation when extrapolated satellite orbit to 7 seconds time. 2010 IEEE.
	Angular rate of test table based on high-speed non-contact measurement (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: Yang L.; Zhao Y.; Zhao Y.; Zhao Y.; Yang L. 收藏 \| 浏览/下载：129/0 \| 提交时间：2013/03/25 This article will introduces a high-speed non-contact method that can measures the angular rate of a test table though an objective perspective. This method adopts a collimator tube that can be measured as a target fixed to the test table and the target corresponds to the angular position of the test table. In the process of the table rotating the camera will to keep track of the objective at a high speed. Due to the high sampling frequency of the high-speed camera instantaneous angular rate of test table can be measured. With pixel subdivision technology its measuring accuracy can be up to 0.02 pixels. We use this methods measured a low-speed test table's angular rate and analyzed the data. The error analysis shows when the rate of the test table is 0.20/s the accuracy of the method can achieve 0.0220%. 2009 IEEE.
	Study and calibration of azimuth effect in multi-position strap-down north seeking system (EI CONFERENCE) 会议论文 OAI收割 7th World Congress on Intelligent Control and Automation, WCICA'08, June 25, 2008 - June 27, 2008, Chongqing, China 作者: Wang Z.; Zhao J.; Wang Z. 收藏 \| 浏览/下载：10/0 \| 提交时间：2013/03/25 In order to reduce the influence of azimuth effect in multi-position strap-down north seeking system its cause of formation is studied based on the precession principle of the dynamically tuned gyro. A detecting system composed by true north prism two Leica theodolites and benchmark prism fixed in the strap-down north seeking system was designed to calibrate the azimuth effect. By two steps many measurements are gone on in every position to eliminate the random error. According to the homologous between the error and the position a sinusoid is made a fit as compensate curve after the error of twelve positions is measured. Then the azimuth effect of the arbitrary position can be corrected by the curve. The experiment result shows that the seeking north standard deviation is only 11.77 after compensation which is considerably less than the 87.75 without correction. 2008 IEEE.
	Simulations and experimental studies of diffuser/nozzle pumps (EI CONFERENCE) 会议论文 OAI收割 4th International Symposium on Precision Mechanical Measurements, August 25, 2008 - August 29, 2009, Hefei/Jiuhua Mountain, Anhui, China 作者: Li W.; Li W. 收藏 \| 浏览/下载：23/0 \| 提交时间：2013/03/25 An investigation of diffuser/nozzle micropumps is presented. Numerical simulations are done using CFD program ANSYS/Flotran. The simulations show when the opening angel is small the flow in the diffuser/nozzle is steady the mass flow is increasing with the adding opening angle. But when the opening angel continues increasing the pressure grads will be bigger than zero. It means that the static pressure is gradually going up along the diverging direction. The fluid near the wall stops flowing because the velocity decreases rapidly and the dynamic pressure is not big enough to overcome the increasing of the static pressure. Finally the fluid flows reversely from the backward position of higher pressure area this makes the separation flow of fluid the diffuser is full of reverse fluid. And this results in the dropping of mass flow at last. The simulations also show that the performance of diffuser with a round inlet is better than that with a sharp inlet. The mass flow of micropumps with different opening angles different inlets are measured. The experimental results agree well with the simulations. 2008 SPIE.