中国科学院机构知识库网格系统: 检索

浏览/检索结果: 共8条，第1-8条

帮助

条数/页：排序方式：
	Consensus of Multi-Agent Systems Under Binary-Valued Measurements and Recursive Projection Algorithm 期刊论文 OAI收割 IEEE TRANSACTIONS ON AUTOMATIC CONTROL, 2020, 卷号: 65, 期号: 6, 页码: 2678-2685 作者: Wang, Ting; Zhang, Hang; Zhao, Yanlong \| 收藏 \| 浏览/下载：41/0 \| 提交时间：2020/09/23 Convergence Consensus algorithm Projection algorithms Noise measurement Estimation Multi-agent systems Approximation algorithms Binary-valued communications convergence convergence rate consensus control estimate multi-agent systems recursive projection algorithm
	Applications of the Bounded Total Variation Denoising Method to Urban Traffic Analysis 期刊论文 OAI收割 EAST ASIAN JOURNAL ON APPLIED MATHEMATICS, 2019, 卷号: 9, 期号: 3, 页码: 622-642 作者: Tang, Shanshan; Yu, Haijun \| 收藏 \| 浏览/下载：48/0 \| 提交时间：2020/01/10 Urban traffic prediction bounded variation denoising noise estimate cluster analysis
	Color filtering method for CFA images based on gradient (EI CONFERENCE) 会议论文 OAI收割 International Conference on Communication Systems and Network Technologies, CSNT 2012, May 11, 2012 - May 13, 2012, Rajkot, Gujrat, India 作者: Wang Y.; Wang Y.; Wang Y.; Wang Y.; Wang Y. 收藏 \| 浏览/下载：34/0 \| 提交时间：2013/03/25 Single-sensor digital cameras capture image by covering the sensor surface with a color filter array(CFA) such that each sensor pixel only samples one of three primary color values three color is R(red) G(green) and B(blue). To render a full-color image need an interpolation process commonly referred to as CFA demosaicking is required to estimate the other two contributions for producing a full-color image. But the noise in imaging sensors not only corrupts the color filter array at the same time introduces artifacts during the color interpolation step and influence quality of images. In order to acquire high quality full-color images adopt a sort of viable and effective interpolation algorithm based on gradient at the time of removing the noise reserve image border and detail information clearly. 2012 IEEE.
	Improved TOPS about direction of arrival estimation for wideband signals (EI CONFERENCE) 会议论文 OAI收割 2011 International Conference on Vibration, Structural Engineering and Measurement, ICVSEM2011, October 21, 2011 - October 23, 2011, Shanghai, China 作者: He B. 收藏 \| 浏览/下载：17/0 \| 提交时间：2013/03/25 The study about the direction-of-arrival (DOA) estimation for wideband signals is a basic topic of Signal Processing. The method called test of orthogonality of projected subspaces (TOPS) does not require initial values to form focusing matrix compared with the coherent signal subspace method (CSSM) but it has poor performance for coherent wideband signals at low signal-to-noise ratio (SNR). Based on the lack of the conventional TOPS this paper reconstructs a set of new matrices with the narrowband correlated matrices coming from the DFT decomposition of the array output and modifies the method frame of the conventional TOPS. So we get a set of reconstructed matrices with full rank corresponding to each frequency bin and which have no array aperture loss. The improved TOPS can estimate the DOA for coherent wideband sources at low SNR and enhances the performance of the conventional TOPS. Simulation results show that the improved TOPS is effective and the total performance of which is similar to the rotational signal-subspace (RSS) method. (2012) Trans Tech Publications.
	The research on statistical properties of TDI-CCD imaging noise (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Imaging Detectors and Applications, May 24, 2011 - May 26, 2011, Beijing, China Gu Y.-Y.; Shen X.-H.; He G.-X. 收藏 \| 浏览/下载：23/0 \| 提交时间：2013/03/25 TDI-CCD can improve the sensitivity of space camera without any degradation of spatial resolution which is widely used in aerospace imaging devices. The article describes the basic working principle and application characteristics of TDI-CCD devices analyses the composition of TDI-CCD imaging noise and propose a new method to analyze TDI-CCD imaging noise with statistical probability distribution. In order to estimate the distribution of gray values affect by noise we introduced the concept of skewness and kurtosis. We design an experiment using constant illumination light source take image with TDI-CCD working at different stage such as stage 16 stage 32 stage 48 stage 64 and stage 96 analyse the characteristics of image noise with the method we proposed experimental results show that the gray values approximately meet normal distribution in large sample cases. 2011 SPIE.
	A MLP-PNN neural network for CCD image super-resolution in wavelet packet domain (EI CONFERENCE) 会议论文 OAI收割 2008 International Conference on Wireless Communications, Networking and Mobile Computing, WiCOM 2008, October 12, 2008 - October 14, 2008, Dalian, China Zhao X.; Fu D.; Zhai L. 收藏 \| 浏览/下载：68/0 \| 提交时间：2013/03/25 Image super-resolution methods process an input image sequence of a scene to obtain a still image with increased resolution. Classical approaches to this problem involve complex iterative minimization procedures typically with high computational costs. In this paper is proposed a novel algorithm for super-resolution that enables a substantial decrease in computer load. First decompose and reconstruct the image by wavelet packet. Before constructing the image use neural network in place of other rebuilding method to reconstruct the coefficients in the wavelet packet domain. Second probabilistic neural network architecture is used to perform a scattered-point interpolation of the image sequence data in the wavelet packet domain. The network kernel function is optimally determined for this problem by a MLP-PNN (Multi Layer Perceptron - Probabilistic Neural Network) trained on synthetic data. Network parameters dependent on the sequence noise level. This super-sampled image is spatially Altered to correct finite pixel size effects to yield the final high-resolution estimate. This method can decrease the calculation cost and get perfect PSNR. Results are presented showing the quality of the proposed method. 2008 IEEE.
	Application of CMOS APS star tracker with large FOV in attitude and angular velocity determination (EI CONFERENCE) 会议论文 OAI收割 Advanced Sensor Systems and Applications III, November 12, 2007 - November 14, 2007, Beijing, China Lu D.; Guang J.; Shaoju W.; Tao C. 收藏 \| 浏览/下载：30/0 \| 提交时间：2013/03/25 The paper deals with the spacecraft attitude determination problem using a new kind of star tracker with large FOV based on CMOS APS. Star tracker has been developed since 1970s and proved to be the most accurate sensor ever used in the spacecraft attitude determination systems. But the traditional CCD star tracker also has some disadvantages such as small FOV high power consumption low sample rate and low working angular rate limit which prevent the use of CCD star tracker in attitude large angle maneuvering process. The new kind of star tracker based on CMOS APS has no such disadvantages and is more applicable on modern low-cost agile small satellites. Its higher sample rate and working angular rate limit over traditional CCD star tracker make it more adapt for spacecraft angular velocity determination. Because of the large FOV of the star tracker the mathematical model of traditional CCD star tracker with a small FOV is not appropriate. So a new mathematical model was quoted to fit the star tracker with a large FOV. An alternative adaptive algorithm was also introduced in the paper. It can help the EKF algorithm work lacking of accurate covariance of the observation noise. An optimal estimation algorithm was used to estimate the angular velocity directly from the star tracker measurements. Mathematic simulation results indicate the CMOS APS star tracker can give accurate attitude information and estimated angular rate. The method can be used as the chief attitude determination system design of low-cost satellite without gyros or be used as a backup strategy in the event of gyro failures to enhance the reliability of the attitude determination system.
	CR image filter methods research based on wavelet-domain hidden markov models (EI CONFERENCE) 会议论文 OAI收割 ICO20: Optical Information Processing, August 21, 2005 - August 26, 2005, Changchun, China 作者: Wang J.-L.; Wang J.-L.; Li D.-Y.; Wang Y.-P. 收藏 \| 浏览/下载：18/0 \| 提交时间：2013/03/25 In the procedure of computed radiography imaging we should firstly get across the characters of kinds of noises and the relationship between the image signals and noises. Based on the specialties of computed radiography (CR) images and medical image processing we have study the filtering methods for computed radiography images noises. On the base of analyzing computed radiography imaging system in detail the author think that the major two noises are Gaussian white noise and Poisson noise. Then the different relationship of between two kinds of noises and signal were studied completely. By considering both the characteristics of computed radiography images and the statistical features of wavelet transformed images a multiscale image filtering algorithm which based on two-state hidden markov model (HMM) and mixture Gaussian statistical model has been used to decrease the Gaussian white noise in computed images. By using EM (Expectation Maximization) algorithm to estimate noise coefficients in each scale and obtain power spectrum matrix then this carried through the syncretized two Filter that are IIR(infinite impulse response) Wiener Filter and HMM according to scale size and achieve the experiments as well as the comparison with other denoising methods were presented at last.