中国科学院机构知识库网格系统: 检索

Sensitivity analysis of gravity anomalies and vertical gravity gradient data for bathymetry inversion 期刊论文 OAI收割
MARINE GEOPHYSICAL RESEARCH, 2019, 卷号: 40, 期号: 1, 页码: 87-96
作者: Wan, Xiaoyun; Ran, Jiangjun; Jin, Shuanggen

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收藏 | 浏览/下载：43/0 | 提交时间：2019/05/23

Gravity anomaly Vertical gravity gradient Bathymetry inversion Accuracy requirement Seafloor topography

A review of recent developments in HASM SCI/SSCI论文 OAI收割
2015
作者: Yue T. X.

收藏 | 浏览/下载：37/0 | 提交时间：2015/12/09

Surface modeling method HASM Error Computational speed Memory requirement Accuracy major terrestrial ecosystems high-speed method high-accuracy dem construction china information integration satellite algorithm climate

A sub-pixel extraction method for the center of the circular structure from spot array calibration target (EI CONFERENCE) 会议论文 OAI收割
2012 3rd International Conference on Information Technology for Manufacturing Systems, ITMS 2012, September 8, 2012 - September 9, 2012, Qingdao, China
作者: Liu Y.; Zhang T.; Yang H.; Gao X.; Liu Y.

收藏 | 浏览/下载：75/0 | 提交时间：2013/03/25

The imaging measurement system must be calibrated before application. In calibration procedure sub-pixel center extraction is the crucial step for the final accuracy. In this paper a new sub-pixel extraction method is proposed. Edge detection at pixel level is obtained using LOG operator then sub-pixel edge detection is realized using the Facet model. Finally the least squares ellipse fitting is operated on the sub-pixel edge to determine the sub-pixel center. Experiment on a series of simulated images indicates that this algorithm is able to realize the center location accuracy of 0.01-0.02 pixel and meets the requirement of sub-pixel level. (2012) Trans Tech Publications Switzerland.

The design of space scanning mirror control system based on optimal tracking controller (EI CONFERENCE) 会议论文 OAI收割
2012 International Conference on Electrical Insulating Materials and Electrical Engineering, EIMEE 2012, May 25, 2012 - May 27, 2012, Shenyang, Liaoning, China
作者: Zhang P.

收藏 | 浏览/下载：19/0 | 提交时间：2013/03/25

Control system of space scanning mirror has high requirement of scanning accuracy. The use of optimal tracking controller simulation experiment of the control system based on optimal tracking controller is carried out. The simulation result instead of traditional PID controller the control system based on optimal tracking controller is designed in comparison with the system based on a PID controller can effectively improve the scanning accuracy of space scanning mirror control system. State space model of the control system is established shows that the scanning mirror control system using optimal tracking controller instead of PID controller has higher scanning accuracy and faster response. (2012) Trans Tech Publications Switzerland.

Tracking error modeling of the theodolite based on GRNN method (EI CONFERENCE) 会议论文 OAI收割
2nd International Conference on Frontiers of Manufacturing and Design Science, ICFMD 2011, December 11, 2011 - December 13, 2011, Taichung, Taiwan
作者: Li M.

收藏 | 浏览/下载：24/0 | 提交时间：2013/03/25

To meet the requirement of high tracking accuracy as well as develop more reasonable evaluation method in this paper the General Regression Neural Network (GRNN) has been applied to build the tracking error model of the theodolite. First we analyze the nonlinear factors in the theodolite. Second we discuss the principle of GRNN including its structure the function as well as its priors. Third we build the tracking error model based on GRNN and verify the model through the different parameters. The result indicated that the network model based on GRNN has high accuracy and good generalization ability. It could instead the real system to a certain extent. The research in this paper has important value to the engineering practice.

An accuracy requirement analysis for LED brightness and color correction system (EI CONFERENCE) 会议论文 OAI收割
2011 International Conference on Transportation, Mechanical, and Electrical Engineering, TMEE 2011, December 16, 2011 - December 18, 2011, Changchun, China
作者: Wang R.

收藏 | 浏览/下载：63/0 | 提交时间：2013/03/25

Brightness and color correction system is working for the color uniform problem of LED display. The correction system can improve LED display's quality greatly. The accuracy of the LED system must consider the accuracy requirements of the color correction system. This paper analyze the accuracy requirements from two aspects. One is that the accuracy requirements should consider the chromatic tolerance for the human eyes the other one is that the accuracy requirements should be associated with the precision of measuring equipment. This paper discuss the accuracy requirement with the CIE1976LUV as a color space to meet the chromatic tolerance of the human eyes and also give an explanation on how the accuracy of the measuring equipment affect the the correction system. Then this paper give a method to ensure the accuracy requirement for the correction system of a LED display. 2011 IEEE.

Technology on fabrication of precise SiC aspherical mirror (EI CONFERENCE) 会议论文 OAI收割
2011 International Conference on Materials and Products Manufacturing Technology, ICMPMT 2011, October 28, 2011 - October 30, 2011, Chengdu, China
Zhang Z.

收藏 | 浏览/下载：26/0 | 提交时间：2013/03/25

This paper represents a technique to produce the large size optical aspherical mirror by using reaction-bonded silicon carbide to meet the material requirements of the space used mirrors based on the characters comparison of all types mirror material. Techniques are described in this paper including the bonding procedure of silicon carbide to form a mirror shape the CCOM technology for aspheric grinding polishing on a home-developed tool -FSGJ-2 and the aspheric profilometry. A specialized Offner Null lens is also developed to measure the aspherical mirror with laser interferometer. With the technology depicted in the paper a 502mm 298 mm off-axis SiC aspherical mirror is successfully made with a surface accuracy better than 1/50rms the final result meets the design requirement. (2011) Trans Tech Publications.

Design and optimization of supporting structure for scanning mirror in aviation remote sensor (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
作者: Yang H.

收藏 | 浏览/下载：30/0 | 提交时间：2013/03/25

An optical supporting structure is studied to improve its structure stiffness and reduce the rotate error to meet the requirement of aviation remote sensor. A formula to calculate fundamental frequency is proposed using Rayleigh-Ritz method and a method of is analyzed. By means of OPTISTRUCT software the maximum fundamental frequency is converted to object function the deformation under the gravity and the mass are assigned to state variable wall thicknesses of the structure are converted to design variables. The analysis and test results indicate that the fundamental frequency of designed optical supporting structure has been improved 37.2 Hz from 96.9 Hz which guarantee the reliability of the sweep mechanism and the rotate error is 4.89 which is satisfied for the rotate accuracy in plunge angle. The method of optimization has a certain instructional significance for the design of supporting structures in aviation remote sensor. 2011 IEEE.

Research on computer control strategy for optical electric tracking system (EI CONFERENCE) 会议论文 OAI收割
2011 IEEE International Conference on Mechatronics and Automation, ICMA 2011, August 7, 2011 - August 10, 2011, Beijing, China
作者: Li M.

收藏 | 浏览/下载：23/0 | 提交时间：2013/03/25

In this paper mathematic model and computer control strategy for optical electrical tracking system have been researched and discussed. First the system's structure and its work process have been analyzed. Second according to the system's moving law the system's mathematic model has been built. As to the computer control strategy trigger guiding two closed loop PID control method as well as compound control method have been applied to satisfy the tracking accuracy. Third we apply the bilinear transformation to get the digital system and the sample time is 800Hz. The simulation results indicate that the maximum tracking error can be limited to less than 0.5 and the regulator time can be 0.04s. Then the control project resonance frequency should be more than 200Hz and the sample frequency should be more than 400Hz to meet the control accuracy requirement. So we can conclude that the system indexes such as swiftness high accuracy as long as real time have been satisfied. And the requirement of mechanical property has been present which is very useful to mechanical working. 2011 IEEE.

Research on servo controller for high speed tracking system (EI CONFERENCE) 会议论文 OAI收割
2011 International Conference on Mechatronic Systems and Automation Systems, MSAS 2011, July 23, 2011 - July 24, 2011, Xi'an, China
作者: Li M.

收藏 | 浏览/下载：17/0 | 提交时间：2013/03/25

To meet requirement of swiftness and minimization for the tracking system as well as realize horizontal high accuracy tracking measurement the automatic servo tracking measurement system has been designed. The two closed loop control bisection method and compound control have been applied into the system. Experimental results show that the maximum tracking error can be limited to less than 0.5and the regulator time can be 0.04s. The control project resonance frequency should be more than 200Hz and the sample frequency should be more than 400Hz to meet the control accuracy requirement. And these specific mechanical properties indexes are useful to mechanical working to make sure the design can be realization. So the research in this paper has important value to the engineering practice. (2011) Trans Tech Publications.