2012
2012
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Record 13 of
Title:Constrained nonnegative matrix factorization for image representation
Author(s):Liu, Haifeng(1); Wu, Zhaohui(1); Li, Xuelong(2); Cai, Deng(3); Huang, Thomas S.(4)Source: IEEE Transactions on Pattern Analysis and Machine Intelligence Volume: 34 Issue: 7 DOI: 10.1109/TPAMI.2011.217 Published: 2012Abstract:Nonnegative matrix factorization (NMF) is a popular technique for finding parts-based, linear representations of nonnegative data. It has been successfully applied in a wide range of applications such as pattern recognition, information retrieval, and computer vision. However, NMF is essentially an unsupervised method and cannot make use of label information. In this paper, we propose a novel semi-supervised matrix decomposition method, called Constrained Nonnegative Matrix Factorization (CNMF), which incorporates the label information as additional constraints. Specifically, we show how explicitly combining label information improves the discriminating power of the resulting matrix decomposition. We explore the proposed CNMF method with two cost function formulations and provide the corresponding update solutions for the optimization problems. Empirical experiments demonstrate the effectiveness of our novel algorithm in comparison to the state-of-the-art approaches through a set of evaluations based on real-world applications. ? 2012 IEEE.Accession Number: 20122115058807 -
Record 14 of
Title:Fabrication and characteristic of polarization-maintaining photonic crystal fiber with two big air holes structure
Author(s):Xue, Xiaomin(1,2); Li, Weinan(1); Wang, Pengfei(1); Lu, Min(1)Source: Fiber and Integrated Optics Volume: 31 Issue: 5 DOI: 10.1080/01468030.2012.712609 Published: September 1, 2012Abstract:In this article, polarization-maintaining photonic crystal fibers with two big air holes, which are based on a kind of multi-component glass, are fabricated by the capillary-stacking and drawing method. The microstructure of the small air holes is found to be well kept through a scanning electron microscope, even with a diameter close to 0.6 μm. Numerical results show that the chromatic dispersion of the proposed fiber with a 125-μm-diameter approaches zero at 1,550 nm. Meanwhile, experimental results display that the beat length of the same photonic crystal fiber is 3.6961 mm at 1,550 nm, and the related polarization extinction ratio and polarization mode dispersion is 17.23889 dB and 2.58321 ps, respectively. ? 2012 Copyright Taylor and Francis Group, LLC.Accession Number: 20124415611288 -
Record 15 of
Title:Design of 30× middle infrared continuous zoom system
Author(s):Jiang, Kai(1,2); Zhou, Sizhong(1); Wang, Yanbin(1); Duan, Jing(1); Zhang, Hengjin(1); Li, Gang(1)Source: Hongwai yu Jiguang Gongcheng/Infrared and Laser Engineering Volume: 41 Issue: 8 DOI: Published: August 2012Abstract:On the basis of a cool 320 × 240 detector with staring focal plane array, a set of 30× middle infrared continuous zoom system was designed. The structural selection and the initial parameter calculation were introduced in detail. Two common infrared materials of Si and Ge were used. To correct off axis aberration, aspheric was accepted. The design results prove that the system works at 3.7-4.8 μm, achieving the zoom of 30-900 mm, large zoom ratio of 30× and F number of 4. At the spatial frequency of 16 lp/mm, the system's MTF value is greater than 0.5. The system can offer a high resolution and excellent images in whole range of the focal length, and its cold shield efficiency is 100%. And it has the advantages of a large zoom ratio, compact structure and short optical length. The system satisfies the design requirements.Accession Number: 20124415622962 -
Record 16 of
Title:RF power amplifier design applied to acoustic optical modulator
Author(s):Hu, Wenjie(1); Luo, Xiujuan(1); Cui, Dongzi(2)Source: 2012 IEEE 5th International Conference on Advanced Computational Intelligence, ICACI 2012 Volume: Issue: DOI: 10.1109/ICACI.2012.6463331 Published: 2012Abstract:This paper proposes a novel procedure of designing a power amplifier with broadband and high linearity, which is applied to acoustic optical modulator. Firstly, a transistor should be suitably chosen, here we accomplish the direct current (DC) simulation in order to get the right quiescent operating point under the platform Advanced Design System 2009 (ADS). Then some stability simulations and measurements were taken to make sure that the amplifier can be unconditionally stable. Finally, we carried out the load pull and source pull simulations to obtain the load and source impedances required, while executing the Harmonic Balance (HB) simulations to verify our design. ? 2012 IEEE.Accession Number: 20131116105448 -
Record 17 of
Title:Optics system design of the middle-wave infrared camera for spatial non-cooperative targets
Author(s):Wang, Hu(1,2); Luo, Jianjun(1); Bai, Yu(3)Source: Guangxue Xuebao/Acta Optica Sinica Volume: 32 Issue: SUPPL.1 DOI: 10.3788/AOS201232.s122001 Published: December 2012Abstract:Based on the spatial non-cooperative target detectors, a design of hybrid diffractive/refractive dual-field-of-view middle-wave infrared optical system is put forward. Compared with the continuous zoom optical system, infrared dual-field-of-view optical system has many advantages, such as simple structure, easy fixing, quick switching and so on. A compact and lightweight infrared dual-field-of-view hybrid diffractive/refractive optical system is designed. The zoom system has intermediate image plane and the zoom group is moved through the optical axis to implement dual-field-of-view. The system consists of only seven lenses, and can realize 160 mm/40 mm dual-field-of-view at the spectrum region of 3.7~4.8 μm, which can obtain the cold shield efficiency of 100%. The design result shows that the system has the advantages of compact structure, high image quality and low price.Accession Number: 20131016087851 -
Record 18 of
Title:Analysis of field of view limited by a multi-line X-ray source and its improvement for grating interferometry
Author(s):Du, Yang(1); Huang, Jianheng(2); Lin, Danying(2); Niu, Hanben(2)Source: Analytical and Bioanalytical Chemistry Volume: 404 Issue: 3 DOI: 10.1007/s00216-012-6178-1 Published: August 2012Abstract:X-ray phase-contrast imaging based on grating interferometry is a technique with the potential to provide absorption, differential phase contrast, and dark-field signals simultaneously. The multi-line X-ray source used recently in grating interferometry has the advantage of high-energy Xrays for imaging of thick samples for most clinical and industrial investigations. However, it has a drawback of limited field of view (FOV), because of the axial extension of the X-ray emission area. In this paper, we analyze the effects of axial extension of the multi-line X-ray source on the FOVand its improvement in terms of Fresnel diffraction theory. Computer simulation results show that the FOV limitation can be overcome by use of an alternative X-ray tube with a specially designed multi-step anode. The FOVof this newly designed X-ray source can be approximately four times larger than that of the multi-line X-ray source in the same emission area. This might be beneficial for the applications of X-ray phase contrast imaging in materials science, biology, medicine, and industry. ? Springer-Verlag 2012.Accession Number: 20123615391600 -
Record 19 of
Title:Research on laser-induced damage of optical glass by metal ion
Author(s):Li, Ning(1,2); Hou, Chaoqi(1); Li, Weinan(1); Hu, Bin(2); Min, Lu(1)Source: 2012 Symposium on Photonics and Optoelectronics, SOPO 2012 Volume: Issue: DOI: 10.1109/SOPO.2012.6271022 Published: 2012Abstract:The laser-induced damage experiments are finished under the conditions that Q-switched Nd glass laser (the output pulse amplitude is 8.7ns, wavelength are times of 1053nm, 527nm, 351nm) effects on the undoped glass-metal ions M0 and the incorporation of metal ions glass M1, M2. The test results show that: with the irradiation of the fundamental laser, the laser-induced damage threshold of M1 is reduced by 23% than M0; with the irradiation of second harmonic light, the laser-induced damage threshold of M2 is reduced by 23% than M0; with the irradiation f third harmonic radiation, the damage threshold of all glass is basically the same. Observed laser-induced damage of glass under optical microscope with fluorescence, we find that only M1 at the fundamental frequency of the laser light irradiation and M2 in the second harmonic of the laser light irradiation have visible damage central damage and crack. Through the analysis we know that the metal ion absorb laser radiation is the direct reason of surface damage reduce of laser damage threshold of glass. ? 2012 IEEE.Accession Number: 20124315589325 -
Record 20 of
Title:Application of focusing capillary in extreme ultraviolet collimator
Author(s):Zhou, Yuanyuan(1,2,3); Zhou, Sizhong(1); Deng, Ying(3)Source: Guangxue Xuebao/Acta Optica Sinica Volume: 32 Issue: 10 DOI: 10.3788/AOS201232.1023001 Published: October 2012Abstract:Through using focusing capillary, the extreme ultraviolet (EUV) light source of collimator is channelled out of flange, and the light beam's divergence angle is controlled to match the collimator's aperture angle. This article analyzes and calculates the case of directly using a light source to illuminate target disk and the light beam cannot cover the diameter of the effective primary mirror. Focusing capillary can make the light beam cover the aperture angle of collimator and the two states of the EUV collimator with and without capillary are tested.The results show that using focusing capillary can expand light beam's divergence angle. Besides, the maximum number of photons without capillary is close to 1×105 and the maximum number of photons with capillary can reach 1×104. The testing data show that the EUV focusing capillary's transmission efficiency can achieve 10% to meet technical index of EUV collimator.Accession Number: 20124815723853 -
Record 21 of
Title:Design of compact infrared zoom lens system
Author(s):Yan, Aqi(1,2); Wu, Dengshan(1); Wang, Hao(1); Cao, Jianzhong(1); Ma, Jingjin(3); Yang, Jianfeng(1); Zhou, Zuofeng(1); Wu, Li(1); Zhang, Jian(1); Zhang, Zhi(1)Source: Advanced Materials Research Volume: 571 Issue: DOI: 10.4028/www.scientific.net/AMR.571.324 Published: 2012Abstract:Infrared zoom lens system with cooled focal plane array (FPA) detector is widely used in military application. Relevant information about optical design can be got easily, but research on infrared zoom lens system with low cost and high image quality for commercial application is less. This paper design a Compact infrared zoom lens system with only four lenses, using an uncooled focal plane array (FPA) with 384×288 pixels with zoom ratio 3:1. Because of large F number and less lenses, transmission of the whole zoom system is greatly improved. NETD and MRTD of infrared system will be satisfying by this compact design. There is no special surface such as diffractive surface, HOE in zoom lens system, and only Ge and Znse infrared materials are chosen which result in lower production cost of infrared zoom lens system for commercial applications. ? (2012) Trans Tech Publications, Switzerland.Accession Number: 20124815717054 -
Record 22 of
Title:The correction of recovered spectral images in a hadamard transform spectral imager based on a digital micro-mirror device
Author(s):Xu, Jun(1,2); Hu, Bingliang(1); Feng, Dazheng(3)Source: Applied Spectroscopy Volume: 66 Issue: 9 DOI: 10.1366/11-06577 Published: September 2012Abstract:The Hadamard transform spectral imager based on a digital micromirror device (DMD) is a novel type of spectral imager developed in recent years. This paper describes the designing scheme of the Hadamard encoding mask and analyzes the encoding process of the detector pixels. Generally the Hadamard encoding mask constructed by DMD cannot completely encode the dispersed spectrum of all the pixels according to the Hadamard matrix; therefore, the spectral images recovered by inverse Hadamard transform inevitably have errors. A correction method for the recovered spectral images is proposed. The experimental results show that this method improves the quality of the recovered spectral images. ? 2012 Society for Applied Spectroscopy.Accession Number: 20123515377229 -
Record 23 of
Title:Bragg gap solitons in PT symmetric lattices with competing nonlinearity
Author(s):Liu, Shuang(1,3); Ma, Caiwen(1); Zhang, Yiqi(2); Lu, Keqing(4)Source: Optics Communications Volume: 285 Issue: 7 DOI: 10.1016/j.optcom.2011.11.065 Published: April 1, 2012Abstract:The effect of competing nonlinearity on beam dynamics in parity-time (PT) symmetric potentials is investigated. By using numerical methods, the existence of gap solitons is demonstrated in the first Bragg band gap of optical (PT) symmetric lattices with competing nonlinearity. Meanwhile, the stability of such solitons is analyzed through introducing a small perturbation to the solitary solutions. The abrupt annihilation of the solitons during propagation demonstrates that the Bragg gap solitons in PT symmetric potentials are not stable. In comparison with the on-site gap solitons, the off-site gap solitons exhibit more robust properties during propagation. ? 2011 Elsevier B.V. All rights reserved.Accession Number: 20120514725847 -
Record 24 of
Title:Research on the interlaced encoding pixels in Hadamard transform spectral imager based on DMD
Author(s):Xu, Jun(1,2); Hu, Bing-Liang(1); Feng, Da-Zheng(3); Zhang, Wen(1,2); Yan, Peng(1)Source: Guang Pu Xue Yu Guang Pu Fen Xi/Spectroscopy and Spectral Analysis Volume: 32 Issue: 1 DOI: 10.3964/j.issn.1000-0593(2012)01-0278-05 Published: January 2012Abstract:The key innovation in Hadamard transform spectral imager (HTSI) introduced recently is the use of digital micro-mirror device (DMD) to encode spectral information. However, it brings some new problems for us to solve synchronously. An interlaced encoding phenomenon caused by the application of DMD to our HTSI was investigated and analyzed. These interlaced encoding pixels were not encoded based on Hadamard transform; therefore they should be processed specially in spectrum recovery. To improve the quality of the recovered spectral images, a positioning method and a decoding method for the interlaced encoding pixels were proposed. In our experiment, we first directed a beam of laser into our HTSI to fill the field of view and labeled the positions of the interlaced encoding pixels. Then we recorded two groups of the encoded images of the target by changing the positions of all the encoding channels on the DMD. The interlaced encoding pixels could be distinguished easily by observing the number of non-zero constants and zero elements in a column vector which is made up of the gray values of a pixel of the encoded images in sequence. The interlaced encoding pixels of the first group of the encoded images turned into the normal Hadamard encoding pixels of the second group of the encoded images. The interlaced encoding pixels of the first group of the encoded images can be decoded through applying inverse Hadamard transform to the corresponding pixels of the second group of the encoded images. The experimental results prove the feasibility of the decoding method.Accession Number: 20120214676675