中国科学院机构知识库网格系统: 检索

A new algorithm for solving the best-fit sphere of optical aspherical surface (EI CONFERENCE) 会议论文 OAI收割
2nd International Conference on Advances in Materials and Manufacturing, ICAMMP 2011, December 16, 2011 - December 18, 2011, Guilin, China
作者: Lin J.; Lu M.

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To solve the best-fit sphere (BFS) accurately is one of the technological keys for the generating and testing of optical aspherical surfaces. This paper presents a new algorithm for solving the BFS of aspherical surfaces to suppress some deficiencies in the existing BFS algorithms. In the proposed approach it is not only suitable for the conic surface a BFS is constructed but also for higher order aspheres. The obtained asphericity and material removal function is more suitable for the machining and test. (2012) Trans Tech Publications which passes through both sides of endpoints in the section o -?xy of the aspherical surfaces Switzerland. the center of the BFS is shifted along the x-axis and its radius of curvature is automatically computed. The variable step size method is proposed to speed up the convergence of the iteration. Through numerically solving the BFS of conic and cubic surface the advantages of the proposed approach are verified. The results show that the proposed approach is of rapid convergence and high accuracy

Research on satellite platform vibration compensation method based on liquid crystal steering system (EI CONFERENCE) 会议论文 OAI收割
2011 SSITE International Conference on Future Material Research and Industry Application, FMRIA 2011, December 1, 2011 - December 2, 2011, Macau, China
作者: Wen M.

收藏 | 浏览/下载：17/0 | 提交时间：2013/03/25

This paper presents the disturbance compensation scheme based on liquid crystal steering system according to the problem that satellite platform vibration affects the tracking and pointing accuracy in space optical communication. The mathematical model of liquid crystal steering system is built. For improving convergence speed the adaptive controller based on posteriori estimation errors RLS lattice filter is designed which not only achieves fast adaptation but also reaches optimal steady-state disturbance compensation. Finally the simulation results show that this control scheme is valid and feasible. (2012) Trans Tech Publications Switzerland.

Application of improved UKF algorithm in initial alignment of SINS (EI CONFERENCE) 会议论文 OAI收割
2011 2nd International Conference on Artificial Intelligence, Management Science and Electronic Commerce, AIMSEC 2011, August 8, 2011 - August 10, 2011, Zhengzhou, China
Su W. X.

收藏 | 浏览/下载：21/0 | 提交时间：2013/03/25

In order to improve the initial alignment accuracy and convergence rate of the SINS system proposed the improved UKF algorithm (AUKF) based on the Unscented Kalman Filter (UKF). Noise statistical characteristics are mostly unknown in real systems when it was effected by the initial value errors and dynamic model errors AUKF algorithm can real-time adjust the covariance of the state vector and observation vector and balance the right ratio of the state information and observation information in the filter results thereby improving the system performance. The experimental results show: The Improved UKF Algorithm enhances the convergence speed and alignment accuracy effectively. 2011 IEEE.

Research on the identification for a nonlinear system (EI CONFERENCE) 会议论文 OAI收割
International Conference on Optical, Electronic Materials and Applications 2011, OEMA 2011, March 4, 2011 - March 6, 2011, Chongqing, China
作者: Liu J.; Jia P.; Liu J.; Liu J.

收藏 | 浏览/下载：32/0 | 提交时间：2013/03/25

The characteristic of the drift error of inertial platform is a high-order nonlinear dynamic system using the neural networks' abilities of universal approximation of differentiable trajectory and capturing system dynamic information this paper presents the drift error identifying project of inertial platform based on Elman networks structure. First the drift error model of inertial platform is established after selecting the input and output for network momentum and alterable speed algorithm is used to speed up the network convergence. On the basis of the algorithm the extended nonlinear node function in the hidden network does not only improve the learning speed of network but also satisfies the need of accuracy on system identification. Through the drift error data measured on inertial platform the training result shows that the scheme achieves satisfied identification results. (2011) Trans Tech Publications.

A new accurate and fast algorithm of sub-pixel image registration (EI CONFERENCE) 会议论文 OAI收割
2010 IEEE 10th International Conference on Signal Processing, ICSP2010, October 24, 2010 - October 28, 2010, Beijing, China
作者: He B.

收藏 | 浏览/下载：25/0 | 提交时间：2013/03/25

In terms of large field view and multi-channel TDICCD remote sensing images previous interpolation methods and curve fitting methods are not able to achieve the high accuracy and fast registration and their noise immunity and robustness is not high. For that this paper presents a more accurate and faster method iterative pixel interpolation and surface fitting method. Firstly the method uses the some overlapping pixels between multi-channel images. Secondly the proposed technique which is based on the maximization of the correlation coefficient function combines an efficient pixel-moving interpolation scheme with surface fitting which makes use of accurate interpolation calculation and fast surface fitting in the iterative process. Finally the accuracy and speed of the algorithm is evaluated by sub-pixel registration of multi-channel images and comparison with other sorts of efficient methods. The experiment results show that the accuracy of the method reaches 0.01 pixels and it is 3 times faster than the interpolation method. In the registration of large field view and multi-channel TDICCD images the method is accurate and fast with greatly high stability noise immunity and robustness. 2010 IEEE.

Focusing control system of photoelectric theodolite based on CAN bus (EI CONFERENCE) 会议论文 OAI收割
2010 2nd International Conference on Computer Engineering and Technology, ICCET 2010, April 16, 2010 - April 18, 2010, Chengdu, China
Mi Y.

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The development trend of focusing control system is high speed reliable control and miniaturization. A new autofocusing control system based on CAN bus is designed which realizes the real-time communication and synchronization control among the distributed control system. A design process of CAN interface based on TJAI050 is presented. The principle of focusing control and the hardware and software design are presented in detail. All experiments show that the control system has the advantages such as high accuracy and anti-interference ability and meets the requirements of high speed and good stability. 2010 IEEE.

Application of adaptive Kalman filter technique in initial alignment of strapdown inertial navigation system (EI CONFERENCE) 会议论文 OAI收割
29th Chinese Control Conference, CCC'10, July 29, 2010 - July 31, 2010, Beijing, China
作者: Liu P.

收藏 | 浏览/下载：28/0 | 提交时间：2013/03/25

In order to improve the alignment precision and convergence speed of strap-down inertial navigation system but in the active system most noise statistical characteristics are unknown an initial alignment method based on Sage-Husa adaptive filter is presented. We also derived the exactitude alignment error model and adaptive Kalman filter equation in the azimuth of small misalignment angle. As usual in this case known the noise statistical characteristics we introduce the adaptive Kalman filter. It uses the information of observed data Kalman filter is suitable on-line estimation noise statistical characteristics and state simultaneously in order to improve the filter continuously so the filter has a higher estimation accuracy than the conventional Kalman filter. By simulating verifying the adaptive Kalman filter enhances the convergence speed and alignment accuracy effectively.

The costs prediction of AOD furnace based on improved RBF neural network (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
Na T.; Zhang D.-J.; Hui L.

收藏 | 浏览/下载：17/0 | 提交时间：2013/03/25

In order to predict the cost a model of cost prediction was set up based on adaptive hierarchical genetic algorithm and RBF neural network. Hierarchical genetic algorithm could optimize the topology and the parameters simultaneously. Compared with simple genetic algorithm it has more efficiency in not only accelerating and stabilizing the parameters training but also determining the structure of the network. Adaptive crossover and mutation probability could accelerate the speed and avoid prematurity. The model was tested by five samples. The results showed that the prediction model has high prediction accuracy which indicated that it was applicable to predict the cost by the model. 2010 IEEE.

The registration of aerial infrared and visible images (EI CONFERENCE) 会议论文 OAI收割
2010 International Conference on Educational and Information Technology, ICEIT 2010, September 17, 2010 - September 19, 2010, Chongqing, China
作者: Liu J.; Wang Y.; Wang Y.; Wang Y.; Wang Y.

收藏 | 浏览/下载：28/0 | 提交时间：2013/03/25

In order to solve the registration problem of different source image existed on aerial image fusion algorithms based on Particle Swarm Optimization (PSO) are applied as search strategy in this paper and Alignment Metric (AM) is used as judgment. This study has realized the different source image registration of infrared and visible light with high speed high accuracy and high reliability. Basically with little restriction of gray level properties a new alignment measure is applied which can efficiently measure the image registration extent and tolerate noise well. Even more the intelligent optimization algorithm - Particle Swarm Optimization (PSO) is combined to improve the registration precision and rate of infrared and visible light. Experimental results indicate that the study attains the registration accuracy of pixel level and every registration time is cut down over 40 percent compared to traditional method. The match algorithm based on AM solves the registration problem that greater differences between different source images are existed on gray and characteristic. At the same time the adoption of combining the intelligent optimization algorithms significantly improves the searching efficiency and convergence speed of the algorithms and the registration result has higher accuracy and stability which builds up solid foundation for different source image fusion. The method in this paper has a magnificent effect and is easy for application and very suitable for engineering use. 2010 IEEE.

Application of adaptive UKF in initial alignment of MINS/GPS integrated navigation system (EI CONFERENCE) 会议论文 OAI收割
2010 3rd International Conference on Advanced Computer Theory and Engineering, ICACTE 2010, August 20, 2010 - August 22, 2010, Chengdu, China
作者: Gao Q.

收藏 | 浏览/下载：32/0 | 提交时间：2013/03/25

In order to overcome the shortcomings of standard unscented Kalman filter (UKF) which are obviously influenced by the error of initial value and the model error of system adaptive UKF which is based on the adaptive principle is applied in initial alignment of the MINS/GPS integrated navigation system. Coarse alignment cannot be done by micro inertial measurement unit (MIMU) itself because of its low precision the method of using magnetometer to assist it with coarse alignment is presented. Simulation results show that the adaptive UKF can overcome the influences of initial values error and inaccurate system model and improve the convergence speed and alignment accuracy effectively. 2010 IEEE.