2011
2011
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Record 397 of
Title:Guiding and confining light in low-index circularly symmetric waveguides
Author(s):Zhang, Wenfu(1,2); Mu, Jian-Wei(3); Huang, Wei-Ping(3); Zhao, Wei(1)Source: IEEE Photonics Journal Volume: 3 Issue: 5 DOI: 10.1109/JPHOT.2011.2167602 Published: 2011Abstract:A circularly symmetric waveguide with a low-index ring inside the core has been proposed and studied comprehensively. By taking advantage of the azimuthal TM01 mode, the structure can confine light inside the low-index region with very high power confinement efficiency. Key characteristic parameters as functions of geometry factors have been investigated through rigorous finite-difference methods. The fabrication tolerance and the material candidate for various potential applications have been discussed. ? 2009 IEEE.Accession Number: 20114114411796 -
Record 398 of
Title:Abrupt transition from wavelength structure to subwavelength structure in a single-crystal superalloy induced by femtosecond laser
Author(s):Zhang, Wei(1,2); Cheng, Guanghua(2); Feng, Qiang(1,3); Cao, Lamei(4); Wang, Fengping(5); Hui, Rongqing(6)Source: Applied Surface Science Volume: 257 Issue: 9 DOI: 10.1016/j.apsusc.2010.12.050 Published: February 15, 2011Abstract:The abrupt transition from low-spatial-frequency laser-induced periodic surface structure (LSFL) to high-spatial-frequency laser-induced periodic surface structure (HSFL) in single-crystal superalloy CMSX-4 during femtosecond laser irradiation has been reported. Microstructural investigations indicate that the transition was initiated by the generation of new grooves on the main ridges of LSFL ripples. This transition resulted in the period of HSFL nearly equal to half of LSFL period. Furthermore, the relationship between both LSFL and HSFL and their parametric dependence was established. The microstructural observation of the abrupt transition provides a morphological evidence of second harmonic generation being responsible for the formation of HSFL. ? 2010 Elsevier B.V.Accession Number: 20110413627604 -
Record 399 of
Title:Static imaging spectropolarimeter
Author(s):Wang, Xin-Quan(1,3); Xiang, Li-Bin(2); Huang, Min(2); Hu, Liang(1); Jing, Juan-Juan(1,3)Source: Guangdianzi Jiguang/Journal of Optoelectronics Laser Volume: 22 Issue: 5 DOI: Published: May 2011Abstract:The principle and instrumental structure of static imaging spectropolarimeter which combines the amplitude modulation and spatially modulated imaging Fourier transform spectrometry technology are presented in this paper. A spectral-polarimetric modulator, which consists of achromatic quarter-wave retarder, multiple-order retarder and polarizer, modulated the Stokes componements of the input light into different wavenumbers, a spatially modulated imaging Fourier transform spectrometer after the spectral-polarimetric modulator got the modulated interferogram in snapshot mode, and the spectrum of the Stokes components could be separated and demodulated from the interferogram. The one dimension of spatial information and its full linear spectropolarimetric information could be acquired in one exposure by the imaging spectropolarimeter, and the other spatial information could be acquired in pushbroom mode.Accession Number: 20112714112235 -
Record 400 of
Title:A review of super-resolution restoration from image sequences
Author(s):Xu, Zhigang(1,2,3); Su, Xiuqin(1)Source: Advanced Materials Research Volume: 204-210 Issue: DOI: 10.4028/www.scientific.net/AMR.204-210.1336. Published: 2011Abstract:Super-resolution (SR) restoration produces one or a set of high resolution images from low-resolution observations. In particular, SR restoration involves many multidisciplinary studies. A review on recent SR restoration approaches was given in this paper. First, we introduced the characteristics and framework of SR restoration. The state of the art in SR restoration was surveyed by taxonomy. Then we summarized and analyzed the existing algorithms of registration and reconstruction. A comparison of performing differences between these methods would only be valid given. After that we discussed the SR problems of color images and compressed videos. At last, we concluded with some thoughts about future directions.Accession Number: 20111213782616 -
Record 401 of
Title:Study and simulation of the intensity modulation-Fourier transform spectropolarimeter
Author(s):Wang, Xin-Quan(1,3); Xiangli, Bin(2); Huang, Min(2); Hu, Liang(1); Jing, Juan-Juan(1,3)Source: Guang Pu Xue Yu Guang Pu Fen Xi/Spectroscopy and Spectral Analysis Volume: 31 Issue: 7 DOI: 10.3964/j.issn.1000-0593(2011)07-1980-05 Published: July 2011Abstract:Intensity modulation-Fourier transform spectropolarimetry (IMFTSP) is a novel technology that combines the intensity modulation spectropolarimetry and Fourier transform spectroscopy. The IMFTSP can obtain full Stokes spectropolarimetric parameters simultaneously, and maintains the throughput (Jacquinot) and multiplex (Fellgett) advantages. Yet aside from this, the IMFTSP has the advantage of reducing the complexity of data processing. The data collecting and spectropolarimetric parameters reconstruction processes were analyzed theoretically in this paper, the theoretical formulas are presented, and a whole process mathematical simulation for the IMFTSP system is introduced. The theory analysis and simulation results proved the feasibility of the IMFTSP.Accession Number: 20112814137357 -
Record 402 of
Title:Advance in imaging spectropolarimeter
Author(s):Wang, Xin-Quan(1,3); Xiangli, Bin(2); Huang, Min(2); Hu, Liang(1); Zhou, Jin-Song(2); Jing, Juan-Juan(1,3)Source: Guang Pu Xue Yu Guang Pu Fen Xi/Spectroscopy and Spectral Analysis Volume: 31 Issue: 7 DOI: 10.3964/j.issn.1000-0593(2011)07-1968-07 Published: July 2011Abstract:Imaging spectropolarimeter (ISP) is a type of novel photoelectric sensor which integrated the functions of imaging, spectrometry and polarimetry. In the present paper, the concept of the ISP is introduced, and the advances in ISP at home and abroad in recent years is reviewed. The principles of ISPs based on novel devices, such as acousto-optic tunable filter (AOTF) and liquid crystal tunable filter (LCTF), are illustrated. In addition, the principles of ISPs developed by adding polarized components to the dispersing-type imaging spectrometer, spatially modulated Fourier transform imaging spectrometer, and computer tomography imaging spectrometer are introduced. Moreover, the trends of ISP are discussed too.Accession Number: 20112814137355 -
Record 403 of
Title:Multimodal learning for multi-label image classification
Author(s):Pang, Yanwei(1); Ma, Zhao(1); Yuan, Yuan(2); Li, Xuelong(2); Wang, Kongqiao(3)Source: Proceedings - International Conference on Image Processing, ICIP Volume: Issue: DOI: 10.1109/ICIP.2011.6115811 Published: 2011Abstract:We tackle the challenge of web image classification using additional tags information. Unlike traditional methods that only use the combination of several low-level features, we try to use semantic concepts to represent images and corresponding tags. At first, we extract the latent topic information by probabilistic latent semantic analysis (pLSA) algorithm, and then use multi-label multiple kernel learning to combine visual and textual features to make a better image classification. In our experiments on PASCAL VOC'07 set and MIR Flickr set, we demonstrate the benefit of using multimodal feature to improve image classification. Specifically, we discover that on the issue of image classification, utilizing latent semantic feature to represent images and associated tags can obtain better classification results than other ways that integrating several low-level features. ? 2011 IEEE.Accession Number: 20120514730019 -
Record 404 of
Title:Advance in interferogram data processing technique
Author(s):Jing, Juan-Juan(1,3); Xiangli, Bin(2); Lü, Qun-Bo(2); Huang, Min(2); Zhou, Jin-Song(2)Source: Guang Pu Xue Yu Guang Pu Fen Xi/Spectroscopy and Spectral Analysis Volume: 31 Issue: 4 DOI: 10.3964/j.issn.1000-0593(2011)04-0865-06 Published: April 2011Abstract:Fourier transform spectrometry is a type of novel information obtaining technology, which integrated the functions of imaging and spectra, but the data that the instrument acquired is the interference data of the target, which is an intermediate data and couldn't be used directly, so data processing must be adopted for the successful application of the interferometric data. In the present paper, data processing techniques are divided into two classes: general-purpose and special-type. First, the advance in universal interferometric data processing technique is introduced, then the special-type interferometric data extracting method and data processing technique is illustrated according to the classification of Fourier transform spectroscopy. Finally, the trends of interferogram data processing technique are discussed.Accession Number: 20112013989922 -
Record 405 of
Title:Face sketch-photo synthesis under multi-dictionary sparse representation framework
Author(s):Wang, Nannan(1); Gao, Xinbo(1); Tao, Dacheng(2); Li, Xuelong(3)Source: Proceedings - 6th International Conference on Image and Graphics, ICIG 2011 Volume: Issue: DOI: 10.1109/ICIG.2011.112 Published: 2011Abstract:Sketch-photo synthesis is one of the important research issues of heterogeneous image transformation. Some available popular synthesis methods, like locally linear embedding (LLE), usually generate sketches or photos with lower definition and blurred details, which reduces the visual quality and the recognition rate across the heterogeneous images. In order to improve the quality of the synthesized images, a multi-dictionary sparse representation based face sketch-photo synthesis model is constructed. In the proposed model, LLE is used to estimate an initial sketch or photo, while the multi-dictionary sparse representation model is applied to generate the high frequency and detail information. Finally, by linear superimposing, the enhanced face sketch or photo can be obtained. Experimental results show that sketches and photos synthesized by the proposed method have higher definition and much richer detail information resulting in a higher face recognition rate between sketches and photos. ? 2011 IEEE.Accession Number: 20113914361921 -
Record 406 of
Title:Image sequence registration based on wavelet transformation and improved multi-restriction criterion
Author(s):Xu, Zhigang(1,2,3); Su, Xiuqin(1)Source: Yi Qi Yi Biao Xue Bao/Chinese Journal of Scientific Instrument Volume: 32 Issue: 10 DOI: Published: October 2011Abstract:Image sequence registration is a key technique for super-resolution reconstruction. To improve the accuracy and speed of image registration, a new method was proposed to register consecutive frames based on wavelet transformation and improved multi-restriction criterion. At first, the wavelet image pyramids of the reference frame and sensed frame are generated to narrow the search space. The feature points are found using Harris detector. Then using the improved multi-restriction criterion, the matching feature points are extracted from the highest level of the image pyramids. Least squares technique is employed to calculate the initial registration parameters. Then the coarse-to-fine hierarchical strategy is applied. The estimates of the mapping function parameters are gradually improved at the following level of the pyramids. Finally, simulated images and actual images were used to carry out test. Experimental results on the image sequences demonstrate that the presented method can quickly obtain registration parameters with high accuracy.Accession Number: 20114714549392 -
Record 407 of
Title:Study of non-classical light imaging technology
Author(s):Chen, Ming-Rui(1,2); Bi, Si-Wen(1); Dou, Xi-Bo(1,2); Liu, Wang-Yun(1)Source: Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment Volume: 637 Issue: 1 SUPPL. DOI: 10.1016/j.nima.2010.02.039 Published: May 1, 2011Abstract:Non-classical light that generates through the optical parametric down-conversion process by using an optical parametric oscillator is introduced, and the imaging system based on the light is built. The characteristics of the light and the spatial resolution of the image are studied. The light irradiates directly on the object plate, producing a mass of signal photons, then the signal photons are collected by the charge-coupled device. The output electrical signal is collected by a high-speed data collection card and processed with software. Finally, the object image is acquired, and its revised image is obtained by image processing. The results indicate that the resolution of the image based on the non-classical infrared light is 1.43 times that of infrared coherent light. The non-classical light can be widely used for high-resolution imaging, spectrum analysis, and micro-biological sample detection. ? 2010 Elsevier B.V. All rights reserved.Accession Number: 20112013983311 -
Record 408 of
Title:Analysis on spectrum recovery for nonuniform sampling interferogram
Author(s):Jing, Juanjuan(1,2); Xiangli, Bin(3); Lü, Qunbo(3)Source: Guangxue Xuebao/Acta Optica Sinica Volume: 31 Issue: 12 DOI: 10.3788/AOS201131.1211006 Published: December 2011Abstract:Traditional fast Fourier transform (FFT) is only useful in uniform sampled interferogram. For nonuniform sampled interferogram, the spectrum recovered by FFT is often distorted when the aliasing is neglected. To solve the problem, nonuniform fast Fourier transform (NUFFT) method is proposed and some mature theories are formed. The NUFFT is applied to the spectrum recovery of interferogram, and the interferogram at different sampling frequency and different degree of nonuniform optical path difference (OPD) is analyzed and simulated. The results indicate that sampling frequency is the main factor that affect the recovery precision for undersampled interferogram condition, while the nonuniform degree of OPD is more affective for oversampled interferogram condition. In the application, data quantity, sampling frequency and the nonuniform degree of OPD must be considered comprehensively to acquire the final design parameter. To ensure the recovery precision, avoiding the undersampling of gotten interferogram is the basic criteria.Accession Number: 20120214672462