中国科学院机构知识库网格系统: 检索

Multiphase transient analysis of horizontal wells during CO2-EOR 期刊论文 OAI收割
JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING, 2022, 卷号: 210, 页码: 9
作者:

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收藏 | 浏览/下载：45/0 | 提交时间：2022/02/17

Horizontal well CO2-EOR Pressure transient analysis Miscibility Corresponding analysis

Detection and analysis of Galileo signal in space anomalies from 2017 to 2018 期刊论文 OAI收割
IET RADAR SONAR AND NAVIGATION, 2020, 卷号: 14, 期号: 11, 页码: 1690-1696
作者: Fan, Lihong; Tu, Rui; Zhang, Rui; Han, Junqiang; Zhang, Pengfei

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收藏 | 浏览/下载：51/0 | 提交时间：2021/11/29

distance measurement error analysis satellite navigation aircraft landing guidance radio receivers Galileo signal space anomalies broadcast ephemeris user navigation SIS anomaly advanced receiver autonomous integrity monitoring precise ephemeris SIS error healthy Galileo satellites corresponding detection thresholds satellite SIS anomalies satellite clock error SIS stability time 7 0 hour time 2 5 hour time 50 0 hour time 4 5 hour

Corner detection using Gabor filters 期刊论文 OAI收割
iet image processing, 2014, 卷号: 8, 期号: 11, 页码: 639-646
作者: Zhang, Wei-Chuan; Wang, Fu-Ping; Zhu, Lei; Zhou, Zuo-Feng

收藏 | 浏览/下载：63/0 | 提交时间：2015/03/19

edge detection Gabor filters grey systems affine transforms Gabor filter contour-based corner detection magnitude response edge contour shape analysis local curvature maxima points planar curve corresponding grey-variation information Canny edge detector normalised magnitude response magnitude response threshold angle threshold detection accuracy localisation accuracy afflne transform noise-robustness

A line mapping based automatic registration algorithm of infrared and visible images 会议论文 OAI收割
5th International Symposium on Photoelectronic Detection and Imaging (ISPDI) - Infrared Imaging and Applications, Beijing, June 25-27, 2013
作者: Ai R(艾锐); Shi ZL(史泽林); Xu DJ(徐德江); Zhang CS(张程硕)

收藏 | 浏览/下载：49/0 | 提交时间：2013/12/26

There exist complex gray mapping relationships among infrared and visible images because of the different imaging mechanisms. The difficulty of infrared and visible image registration is to find a reasonable similarity definition. In this paper, we develop a novel image similarity called implicit linesegment similarity(ILS) and a registration algorithm of infrared and visible images based on ILS. Essentially, the algorithm achieves image registration by aligning the corresponding line segment features in two images. First, we extract line segment features and record their coordinate positions in one of the images, and map these line segments into the second image based on the geometric transformation model. Then we iteratively maximize the degree of similarity between the line segment features and correspondence regions in the second image to obtain the model parameters. The advantage of doing this is no need directly measuring the gray similarity between the two images. We adopt a multi-resolution analysis method to calculate the model parameters from coarse to fine on Gaussian scale space. The geometric transformation parameters are finally obtained by the improved Powell algorithm. Comparative experiments demonstrate that the proposed algorithm can effectively achieve the automatic registration for infrared and visible images, and under considerable accuracy it makes a more significant improvement on computational efficiency and anti-noise ability than previously proposed algorithms.

Analysis on the influence of random vibration on MEMS gyro precision and error compensation (EI CONFERENCE) 会议论文 OAI收割
2011 3rd International Conference on Mechanical and Electronics Engineering, ICMEE 2011, September 23, 2011 - September 25, 2011, Hefei, China
作者: Li M.

收藏 | 浏览/下载：37/0 | 提交时间：2013/03/25

In order to improve its precision in dynamic environment a Kalman filter was designed. Firstly two sets of random drift data of MEMS gyro were respectively analysed and it was found that the variance of random drift under random vibration significantly increased and its mean also changed. Then calculation results show that attitude angle error under random vibration is 2.6 while in the static test it is 0.25. Analysis on the characteristics of random drift was carried out and it is found that it can be treated as stable normally distributed random signal. Finally a corresponding Kalman filter was designed. The results indicated that after filtering the variance of random drift is reduced to 0.0282 26.4% of pre-filtering and the attitude angle error is reduced to 1.5 57.7% of pre-filtering. The above method can effectively compensate for the attitude angle error of MEMS gyro caused by random vibration. This study can be a reference to the application of low-cost MEMS gyro in aircraft navigation. (2012) Trans Tech Publications Switzerland.

The study of the experiment with oil shale characteristics (EI CONFERENCE) 会议论文 OAI收割
2011 International Conference on Materials for Renewable Energy and Environment, ICMREE2011, May 20, 2011 - May 22, 2011, Shanghai, China
Zhao X.; Xiong W.

收藏 | 浏览/下载：40/0 | 提交时间：2013/03/25

This is great for the actual state of the world's energy shortage. The experiment oil shale from Jilin Huadian were studied and analyzed by this paper it carried on the analysis using regression analysis's method to the tentative data to obtains the experimental correlation between the calorific capacity and volatile. According to the characteristics of oil shale Providing a reference for the corresponding professionals of improving combustion efficiency of oil shale. 2011 IEEE.

Non-linear compensation algorithm of LOS locating in aerial remote sensor (EI CONFERENCE) 会议论文 OAI收割
2011 International Conference on Electronic and Mechanical Engineering and Information Technology, EMEIT 2011, August 12, 2011 - August 14, 2011, Harbin, China
作者: Li J.; Li Y.; Li Y.; Li Y.; Li Y.

收藏 | 浏览/下载：48/0 | 提交时间：2013/03/25

A non-linear light-of-sight(LOS) locating compensation algorithm for certain aerial remote sensor is presented in this paper. The LOS locating system is composed of two main components which are an inertial reference frame to provide coarse LOS locating and a 2-axis Fast Steering Mirror to remove the frame's residual error. The azimuth and elevation of LOS are both affected by the FSM two-degree-of-freedom rotation which should be dealt with to raise the accuracy of LOS location. This paper extrapolates LOS locating algorithm of FSM by coordinate transformation and gives corresponding deviation analysis for different LOS poiting angles. It is found that the angle deviation grows rapidly with range of FSM's travel enlarging so the deviation must be eliminated. Through the data analysis for deviation a non-linear compensation algorithm is proved effective to reduce the error of LOS significantly. Taking LOS changing in [-3 deg 3 deg] as an example two analytic expressions are given and the LOS locating accuracy rises by 34 times compared with non-linear compensation unused and the cross coupling of LOS loating is 0.08%. 2011 IEEE.

Gimbal displacement error analysis on an electro-optical seeker (EI CONFERENCE) 会议论文 OAI收割
Optical Design and Testing IV, October 18, 2010 - October 20, 2010, Beijing, China
作者: Zhang X.; Zhang X.; Zhang X.

收藏 | 浏览/下载：43/0 | 提交时间：2013/03/25

It is essential to analyze the gimbal displacement errors for a seeker due to the importance for cueing of targets and tracking for the final approach. Otherwise for a seeker electro-driven with a concentric glass dome the large errors will decrease the picking pointing and tracking precision rooted from the displacement errors existing between the rotation center of the optical system and the gimbal. And the gimbaled camera system displacement errors are never eliminated but reduced due to the geometric errors consists of geometric tolerances of gimbal structure manufacture installation and vibration coming from working environment. In this paper the gimbal displacement errors in an electro-optically stabilized platform resulting from geometric errors and environment errors were analyzed and shown in detail. The mathematical modal of the gimbal displacement errors created based on multi-body dynamics demonstrated the connection between the gimbal displacement errors and the stabilized platform. Taking a visible light image seeker as a case the diameter is 120mm and the geometric tolerances came from the values of primary design and the vibration data came from the environmental vibration test on the pitch-yaw seeker and at the same time the errors resulting from installation were considered too. Based on calculating the maximum gimbal displacement error will reach to 0.2mm for pitching angle smaller than 40 and yawing angle smaller than 60. However the critical parts have been found out according to the probability theory and the reliability analysis successfully used in the paper and finally the maximum gimbal displacement error reduced to 0.1mm which is acceptable corresponding to the picking pointing and tracking precision for an optical imaging seeker. 2010 Copyright SPIE - The International Society for Optical Engineering.

Electromagnetic radiation test of power driver module in optical tracking system and electromagnetic compatibility (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: Yu H.

收藏 | 浏览/下载：39/0 | 提交时间：2013/03/25

In order to solve the conductive ring module's interference problems measured the electromagnetic radiation of Power drive module and used test results analysis the electromagnetic compatibility of the conductive ring identified and implemented appropriate EMC (electromagnetic compatibility) measures. When optical tracking system working test equipment can not be fixed. Therefore from the electromagnetic radiation theory the paper analyzed the electromagnetic radiation of the power drive module. From it determine the EMC pre-compliance test method for electromagnetic radiation of power drive module. Based on Test results calculate the interference voltage of wire in Conductive ring and then determine the corresponding EMC method. The results show that when The power drive module Radiate Electromagnetic waves wires would coupled common mode interference voltage its frequency is 3MHz amplitude is about 10V it would interfered the operation of sensor. By reducing the area of ground loops used shielded cables final rule out the interference. 2010 IEEE.

Configuring an electrostatic membrane reflector with potentials exerted on distributed electrodes (EI CONFERENCE) 会议论文 OAI收割
2009 IEEE International Conference on Mechatronics and Automation, ICMA 2009, August 9, 2009 - August 12, 2009, Changchun, China
作者: Zhang P.; Shi G.

收藏 | 浏览/下载：30/0 | 提交时间：2013/03/25

Electrostatic membrane reflector (EMR) is very promised for optical quality application with the merits of utra-lightweight and flexible. Configuring a circular membrane reflector with electrostatic potentials exerted on distributed electrodes can approximatively produce a parabolic shape. A 300mm EMR (made from polyimide) stretched by distributed electrodes below is designed and the number of concentric electrodes needed for membrane shape forming is analysed. First based on an analytical solution of Poisson's equation determine the membrane control matrix by finding influence functions of 3 concentric electrodes and 6 control points on membrane surface in order to compute the needed voltages exerted on the distributed electrodes by the method of least-squares fitting. Then the final shape solved by finite element analysis with ANSYS is contrasted with the paraboloid and deviates greatly when the central displacement of membrane is beyond 2.5mm but in this range increasing the number of electrodes and control points will get a better shape. The corresponding errors are analyzed and the control method is concluded. Only using the integrated method of analytical computation numerical analysis and experiment the membrane shape of certain central displacement can be exactly predicted and controlled. 2009 IEEE.