中国科学院机构知识库网格系统: 检索

A hybrid method for reconstruction of three-dimensional heterogeneous porous media from two-dimensional images 期刊论文 OAI收割
JOURNAL OF ASIAN EARTH SCIENCES, 2019, 卷号: 178, 页码: 193-203
作者: Ji LL(姬莉莉); Lin M(林缅); Jiang WB(江文滨); Cao GH(曹高辉)

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收藏 | 浏览/下载：43/0 | 提交时间：2018/11/01

Heterogeneous porous media Reconstruction The hybrid method Tight sandstones Pore-size distribution

Integrated optimization method for coupling parametrization design of complex space system (EI CONFERENCE) 会议论文 OAI收割
2012 3rd International Conference on System Science, Engineering Design and Manufacturing Informatization, ICSEM 2012, October 20, 2012 - October 21, 2012, Chengdu, China
作者: Han C.-S.; Wen M.

收藏 | 浏览/下载：138/0 | 提交时间：2013/03/25

This paper investigates the problem of optimization method for coupling parametrization design of complex space system. The objective is to develop an integrated optimization framework to design complex space system. An improved collaborative optimization (ICO) strategy for complex design using hybrid optimization algorithm is proposed which associates genetic algorithm (GA) with tabu search (TS). A multi-objective function with penalty terms for the systemlevel optimization and a relax factor for the subsystem optimization are adopted which can avoid unsolvability or converging difficulty. The results demonstrate the applicability and effectiveness of the proposed design methodology. 2012 IEEE.

A hybrid median filter for enhancing dim small point targets and its fast implementation (EI CONFERENCE) 会议论文 OAI收割
2011 International Conference on Multimedia and Signal Processing, CMSP 2011, May 14, 2011 - May 15, 2011, Guilin, Guangxi, China
Yang Q.

收藏 | 浏览/下载：22/0 | 提交时间：2013/03/25

Weak stars and middle altitude orbit satellites or high altitude orbit satellites are presented as dim point targets in images of astronomical observation. They have low intensity and occupy few pixels in image. In most situations the background of sky is always ununiform and there exists pulse noises. Thus results in targets submerging in background noises and low signal noise ratio (SNR). Median filter is an effective method for removing pulse noise. But it can blur image after modifying gray of non-noise pixels when image has low SNR. A hybrid median filter algorithm is proposed to process low SNR dim point targets image. The newly proposed method can suppress the pulse noises also can increase target $SNR$ and does not add extra fake targets. The time complexity of median filter is O(N2)(N is the widow size) and is difficult to implement in hardware. For quasi real time application a fast implementation of our hybrid median filter is proposed to reduce the time complexity to O(N). Experimental results show that the newly proposed algorithm is superior to ordinary median filter and fast median filter by comparing visual effect and performance. 2011 IEEE.

Panoramic aerial camera image motion measurement using a hybrid system (EI CONFERENCE) 会议论文 OAI收割
2010 3rd IEEE International Conference on Computer Science and Information Technology, ICCSIT 2010, July 9, 2010 - July 11, 2010, Chengdu, China
作者: Jia P.

收藏 | 浏览/下载：28/0 | 提交时间：2013/03/25

Image motion compensation is significantly important for aerial camera photograph. To execute the compensation we must determine the image motion exactly. This paper proposes a method of real-time image motion measurement for panoramic aerial cameras based on image processing using a hybrid system. Two cameras are simultaneously used in the hybrid system. One main linear CCD for imaging while the other auxiliary low resolution high frame rate area CCD for determining the image motion based on 2D spatial correlation. The demanding computational requirements for the real-time 2D spatial correlation are covered by a joint transform optical correlator. Simulation test results show that the accuracy is improved and the measurement error is within 0.2 pixels for input images with SNR=1 dB. 2010 IEEE.

Pre-process technique study of a high performance remote image sensor structural Finite Element Analysis (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
作者: Zhang L.; Xu Y.-S.; Zhang L.

收藏 | 浏览/下载：27/0 | 提交时间：2013/03/25

High precision structural Finite Element Analysis (FEA) results are required in the development of a remote image sensor. HperMesh and MSC. Nastran are employed in the image sensor structural FEA. This paper discusses some technical issues about the Finite Element (FE) modeling of the image sensor. In order to obtain authentic analysis results the part-to-whole handling schema i.e. handling method and research work is implemented in a small part of the model firstly and a revised method is used in the whole structural in succession has been proposed. Some emphasis is mainly put on the FE handling of bolted joint bearing and inter-element connection. The interface handling methods such as CBEAM plus partial MPC bolted joint model hybrid element bearing model and RBE3 beam-to-solid connection have been produced and successfully implemented in the image sensor structural FEA. 2010 IEEE.

Electric-field-induced effective anchoring energy in nematic liquid crystal (EI CONFERENCE) 会议论文 OAI收割
2010 International Conference on Display and Photonics, July 12, 2010 - July 13, 2010, Nanjing, China
Ye W.; Zhang Z.; Xing H.; Yang G.; Chen G.

收藏 | 浏览/下载：20/0 | 提交时间：2013/03/25

Electric-field-induced effective anchoring energy in nematic liquid crystal is investigated taking surface and flexoelectric polarization into consideration. The analytical expressions of effective anchoring energy for both bottom and upper substrate containing these two polarizations are derived. The effective anchoring strength for both bottom and upper substrate is also obtained by means of a systematic method which is relevant to magnitude of two polarizations and determined by the applied voltage U. Applying the obtained expressions into an original weak anchoring hybrid aligned nematic cell the effective anchoring strength are determined with the different magnitudes of two polarizations and the different applied voltage U.

Study particle filter tracking and detection algorithms based on DSP signal processors (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
Dong Y.; Chuan W.

收藏 | 浏览/下载：20/0 | 提交时间：2013/03/25

In Video tracking detection and tracking usually need two algorithms. The process is complex and need much time which detection and tracking are. In this paper a hybrid valued sequential state vector is formulated. The state vector is characterized by information of target appearance flag and of location. Particle filter-based method implements detection and tracking at one time. In order to reduce process time and think of pixel position in tracking field feature histogram of luminance is as observe vector and used posterior estimate. In this paper the luminance component is derived and target is recognized and tracked through image processor based on DSP in order to implementing real-time. The experimental results confirm that method can detect and track the object in real-time successfully when the number of particles is 160. The method is robust for rolling scale and partial occlusion. 2010 IEEE.

Athermal design of hybrid refractive/harmonic diffractive optical system for far-infrared multi-band (EI CONFERENCE) 会议论文 OAI收割
4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies, November 19, 2008 - November 21, 2008, Chengdu, China
作者: Liu Y.; Liu Y.; Zhang H.; Zhang H.; Sun Q.

收藏 | 浏览/下载：30/0 | 提交时间：2013/03/25

In order to get enough information about the target avoid big chromatic aberration as a result of wide spectrum and the complexity of optical system and adapt different special environment temperature a hybrid refractive/harmonic diffractive optical system in far-infrared multi-band is described in the paper. This diffractive optical system has been designed an athermalized multi-band imaging system with harmonic diffractive element in 15-50m spectrum based on larger 1dispersion capability and particular thermal dispersive power of harmonic diffractive element. Then at the temperature range from 0C to 40C this design can simultaneously meet with all requirements of the imaging system in five harmonic wave bands including15.8-16.2m 18.5-20m 23-25m 30.5-33.5m and 46-50m. In each harmonic wave band the magnification changes as a function of wavelength which creates image registration error. To compensate this shortcoming a zoom optical system is designed with three lenses by means of optical two- component method. The design results show that the hybrid refractive/harmonic diffractive optical system can realize athermalized and achromatic design and the zoom optical system makes half image height at 3.53mm in every harmonic wave band and still realizes aberration compensation action. In the five harmonic wave bands each optical transfer function approaches the diffraction limit at ambient temperature range of 0C to 40C. Finally the system realizes the requirements of portability mini-type and ease for fabrication. 2009 SPIE.

Design of aspherical surfaces for panoramic imagers using multipopulations genetic algorithm (EI CONFERENCE) 会议论文 OAI收割
4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies, November 19, 2008 - November 21, 2008, Chengdu, China
作者: Jin C.-S.; Wang L.-P.; Liang Z.-Z.

收藏 | 浏览/下载：30/0 | 提交时间：2013/03/25

A design method of aspherical surface for panoramic imaging system with two mirrors using multi-populations genetic algorithms is proposed. Astigmatism induced by mirrors may significantly compromise image resolution. To solve this problem we induced algebraic expression of astigmatism in panoramic imager based on generalized Coddington equation and theory of geometric optics. Then we propose an optimization process for mirror profile design to eliminate astigmatism and provide purposely-designed projection formula with aid of MPGA. A series of polynomial expressions of aspherical surfaces are obtained and procedures of the design are presented. In order to facilitate ray tracing and aberration calculation even asphere surface model is obtained by using of hybrid schemes combining MPGA and damped least squares. Finally a prototype of the catadioptric panoramic imager has been developed and panoramic ring image is obtained. 2009 SPIE.

Study on color image tracking and detection algorithms based on particle filter (EI CONFERENCE) 会议论文 OAI收割
International Symposium on Photoelectronic Detection and Imaging 2009: Advances in Infrared Imaging and Applications, June 17, 2009 - June 19, 2009, Beijing, China
Wu C.; Sun H.-J.; Yang D.

收藏 | 浏览/下载：20/0 | 提交时间：2013/03/25

In Video tracking detection and tracking need two algorithms. The process is complex and need much time which detection and tracking is. In this paper a hybrid valued sequential state vector is formulated. The state vector is characterized by information of target appearance and of location. Particle filter-based method implements detection and tracking. In order to reduce process time and think of pixel position in tracking field feature histogram of color-based is as observe vector and used posterior estimate. The experimental results confirm that method can detect and track object in 17.68ms successfully when the number of particles is 160. The method is robust for rolling scale and partial occlusion. 2009 SPIE.