2013
2013
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Record 265 of
Title:White-light Spectro-Polarimetric imaging for material classification
Author(s):Bu, Fan(1,2); Qiu, Yuehong(1); Jiang, Baotan(1); Liu, Hui(1,2)Source: Journal of Computational Information Systems Volume: 9 Issue: 4 DOI: Published: February 15, 2013Abstract:A novel technique for material classification ultilizing Spectro-Polarimetric information is presented. Based on experimental white-light Spectro-Polarimetric CCD camera, we obtain a variety of Spectro-Polarimetric images of natural objects and artificial targets. Compared with traditional images, Spectro-Polarimetric images have much complementary and redundancy information that can be used to easily distinguish different materials. Furthermore, DOLP calculated from Stokes-Muller parameters images can show their advantages in quantization. Therefore, we can draw conclusions that Spectro-Polarimetric detecting is superior to conventional photometric detecting, and it can play an important role in military target identification. Copyright ? 2013 Binary Information Press.Accession Number: 20131516191852 -
Record 266 of
Title:A real-time image magnificationtechnology based on edge prediction
Author(s):Huang, Biao(1,2); Tian, Yan(1); Yao, Dawei(1); Yang, Xiaojun(1)Source: Hongwai yu Jiguang Gongcheng/Infrared and Laser Engineering Volume: 42 Issue: SUPPL.1 DOI: Published: 2013Abstract:To solve the problem of edge blurring and edge jaggingIn image zooming process, a new image magnification algorithm based on edge prediction was proposed. In the algorithm, an image was firstly divided into a few sub-region units and then edges of the magnified image were predicted according to the correlation of the pixels in sub-region units of the original image, from which both the non-edge pixels and the edge pixels of the desired image could be found. Finally, the non-edge pixels and the edge pixels were calculated by liner interpolation in different regions and diagonal interpolation respectively, which effectively suppress the edge blurring and edge jagging. The algorithm could magnify a gray image to any times within limits with acceptable result. After comparing with some other algorithms and testing the practical performance of the algorithm in hardware device it turns out that the algorithm has clear advantages over the other algorithms in terms of quality and the relatively low time complexity which is slightly higher than the time complexity of the bilinear. Consequently, the algorithm can be used for both hardware and software solutions to video image.Accession Number: 20134416940661 -
Record 267 of
Title:Femtosecond laser pulses for drilling the shaped micro-hole of turbine blades
Author(s):Jia, Hai-Ni(1); Yang, Xiao-Jun(1); Zhao, Wei(1); Zhao, Hua-Long(1); Du, Xu(2); Yang, Yong(1)Source: Chinese Physics Letters Volume: 30 Issue: 4 DOI: 10.1088/0256-307X/30/4/044202 Published: April 2013Abstract:We design a set of processing devices to drill the shaped holes of turbine blades by using a femtosecond laser which outputs 1064 nm 5 W pulses at 100 kHz, investigate the mechanism of the femtosecond laser interaction with metals, and demonstrate that ultrafast laser drilling has distinct strong points against electric spark and longer laser pulse processing. The advantages related to no recast layer, no thermal effect, no micro crack, high precision, and high processing efficiency are carried out. ? 2013 Chinese Physical Society and IOP Publishing Ltd.Accession Number: 20220711660616 -
Record 268 of
Title:Error analysis of stochastic gradient descent ranking
Author(s):Chen, Hong(1,2); Tang, Yi(3); Li, Luoqing(4); Yuan, Yuan(3); Li, Xuelong(3); Tang, Yuanyan(2)Source: IEEE Transactions on Cybernetics Volume: 43 Issue: 3 DOI: 10.1109/TSMCB.2012.2217957 Published: June 2013Abstract:Ranking is always an important task in machine learning and information retrieval, e.g., collaborative filtering, recommender systems, drug discovery, etc. A kernel-based stochastic gradient descent algorithm with the least squares loss is proposed for ranking in this paper. The implementation of this algorithm is simple, and an expression of the solution is derived via a sampling operator and an integral operator. An explicit convergence rate for leaning a ranking function is given in terms of the suitable choices of the step size and the regularization parameter. The analysis technique used here is capacity independent and is novel in error analysis of ranking learning. Experimental results on real-world data have shown the effectiveness of the proposed algorithm in ranking tasks, which verifies the theoretical analysis in ranking error. ? 2013 IEEE.Accession Number: 20135117116134 -
Record 269 of
Title:Optical system design of polarization imaging spectrometer for ground-based astronomical observation
Author(s):Chang, Lingying(1); Zhao, Baochang(2); Qiu, Yuehong(2); Yao, Dawei(2)Source: Guangxue Xuebao/Acta Optica Sinica Volume: 33 Issue: DOI: 10.3788/AOS201333.s222002 Published: December 10, 2013Abstract:With the development of astrophysics, the astrophysics demands are higher and higher. Astronomical spectral polarization observation can obtain more object information, to provide comprehensive data for further research. On the basis of the 2.16 m astronomical telescope, a polarization imaging spectrometer based on acousto-optic tunable filter is designed, with spectral range of 450~900 nm and the number of spectral channels of 128. As a kind of light splitted element, the acousto-optic tunable filter (AOTF) can obtain image spectral polarization information at the same time. The polarization imaging spectrometer consists of telescope system, acousto-optic imaging system tuned filter, telescope collimation system, compensation, compensation of imaging system and detector, etc. The work principle of AOTF is introduced. Then, design parameters of each optical subsystem are discussed. Finally, the results of optical design are presented. The whole system is achromatized from 0.45 to 0.9 μm with modulated transfer function (MTF) reaching 0.5 under imaging resolution of 32 lp/mm.Accession Number: 20143700064589 -
Record 270 of
Title:Auto-focus algorithm of digital camera based on optical flow estimation
Author(s):Guo, Huinan(1); Cao, Jianzhong(1); Zhou, Zuofeng(1); Dong, Xiaokun(1); Liu, Qing(1); Ma, Nan(2)Source: Hongwai yu Jiguang Gongcheng/Infrared and Laser Engineering Volume: 42 Issue: 12 DOI: Published: December 2013Abstract:Auto-Focus technique is a main approach to hunt clear images which plays an important role in digital camera application. According to several unknown target under complicated condition, a novel auto-focus algorithm was proposed based on optical flow estimation. By calculating the optical flow of each input frame, the moving targets in scene image were tested as well as according to the moving characteristic, the interested real target was judged. Brenner sharpness evaluation method was improved. Meanwhile the evaluation function was established using two dimensions edge-gradient information. The response sensitivity of evaluation function was also increased via nonlinear-gain coefficient the impact of noise on evaluation value was decreased. Experimental results show that the proposed method can distinguish the interested main target in 50 times depths of field of different targets and evaluate the definition of varied images with random noise in 0.02 variance value effectively. And it is of a good ability of robustness for different images, Brenner function improves the peak stability margin 1 to 4 times by the algorithm, and it can be easily achieved on hardware.Accession Number: 20140817349992 -
Record 271 of
Title:Optical properties of Yb3+-doped silicate glasses waveguides formed by low-dose oxygen ion implantation and effects of annealing
Author(s):Liu, Chun-Xiao(1,2); Cheng, Shu(3); Guo, Hai-Tao(2); Li, Wei-Nan(2); Wei, Wei(2,4); Peng, Bo(2,4)Source: Optik Volume: 124 Issue: 14 DOI: 10.1016/j.ijleo.2012.05.019 Published: July 2013Abstract:The planar waveguide, to our knowledge, has been firstly fabricated in the Yb3+-doped silicate glass by 6.0 MeV O3+ ion implantation at a dose of 6 × 1014 ions/cm2. The guiding properties are characterized by the prism-coupling and end-face coupling methods with a He-Ne beam. The dark-mode spectra and near-field intensity distribution are measured before and after annealing at 250 °C for 1 h in air. The results indicate that the thermal treatment can enhance the propagation properties with preserving the effective refractive indices well. The refractive index profile of the planar waveguide is reconstructed by the reflectivity calculation method, which shows a typical "enhanced well + optical barrier" distribution. The SRIM'2006 code is carried out to simulate the energy loss during the implantation in order to obtain a better understanding of the waveguide formation. ? 2012 Elsevier GmbH.Accession Number: 20132216371262 -
Record 272 of
Title:A research on navigation star catalog selection algorithm based on SVM
Author(s):Liu, Fu Cheng(1,2); Liu, Zhao Hui(1,2); Liu, Wen(1,2); Liang, Dong Sheng(1,2); Cui, Kai(1,2); Yuan, Hui(1,2)Source: Advanced Materials Research Volume: 706-708 Issue: DOI: 10.4028/www.scientific.net/AMR.706-708.613 Published: 2013Abstract:A navigation star catalog (NSC) selection algorithm via support vector machine (SVM) is proposed in this paper. The sphere spiral method is utilized to generate the sampling boresight directions by virtue of obtaining the uniform sampling data. Then the theory of regression analysis methods is adopted to extract the NSC, and an evenly distributed and small capacity NSC is obtained. Two criterions, namely a global criterion and a local criterion, are defined as the uniformity criteria to test the performance of the NSC generated. Simulations show that, compared with MFM, magnitude weighted method (MWM) and self-organizing algorithm(S-OA), the Boltzmann entropy (B.e) of SVM selection algorithm (SVM-SA) is the minimum, to 0.00207. Simultaneously, under the conditions such as the same field of view (FOV) and elimination of the hole, both the number of guide stars (NGS) and standard deviation (std) of SVM-SA is the least, respectively 7668 and 2.17. Consequently, the SVM-SA is optimal in terms of the NGS and the uniform distribution, and has also a strong adaptability. ? (2013) Trans Tech Publications, Switzerland.Accession Number: 20132916505304 -
Record 273 of
Title:A single-walled carbon nanotube wall paper as an absorber for simultaneously achieving passively mode-locked and Q-switched Yb-doped fiber lasers
Author(s):Li, Xiaohui(1,2); Wang, Yishan(2); Wang, Yonggang(3); Wang, Qijie(1); Zhao, Wei(2); Zhang, Yongzhe(1); Ya, Xia(4); Zhang, Ying(4)Source: Proceedings - Winter Simulation Conference Volume: Issue: DOI: 10.1109/INEC.2013.6465978 Published: 2013Abstract:We demonstrate a fiber ring laser based on a single-walled carbon nanotube (SWCNT) wall paper absorber. It is found that the proposed Yb-doped fiber laser can either be operated in the mode-locked states or Q-switched states. First, SWCNT wall paper acts as a mode locker when the pump power is below 80 mW. Self-started mode locking can be obtained when the pump power is about 47 mW. The proposed Yb-doped mode-locked fiber lasers can be operated in the dissipative soliton regime that the spectra have a narrow peak. Second, SWCNT wall paper acts as a Q switcher when the pump power is above 80 mW. The Yb-doped fiber laser can work in the Q-switched states at higher pump power which is quite different from the conventional pulse fiber lasers. The repetition rate increases from 30 kHz to 50 kHz and the pulse duration decreases from 2.7 μs to 1 μs with the increase of pump power. This is due to the SWCNT wall paper induced loss in the cavity which leads to Q-switched state at higher pump powers. The combination of the Q-switching and mode-locking in one fiber laser have potential application in the fields that require different pulse fiber lasers. ? 2013 IEEE.Accession Number: 20131116117468 -
Record 274 of
Title:A study of femtosecond laser machining technology applied in air-film holes on turbine blades
Author(s):Zhao, Hualong(1); Zhu, Wenyu(1); Yang, Xiaojun(1); Gao, Shifang(2); Zhao, Hongyan(3)Source: Applied Mechanics and Materials Volume: 268 Issue: PART 1 DOI: 10.4028/www.scientific.net/AMM.268-270.487 Published: 2013Abstract:Femtosecond laser with the features of ultrashort pulse duration and ultrahigh peak power can achieve "cold" machining. The recast layer and micro-cracks of the hole wall can be reduced effectively by applying femtosecond laser in processing air-film holes on turbine blades, and the machining accuracy and consistency of the hole shape will increase. In this paper, the high-speed rotating femtosecond laser beam is adopted in several currently used turbine blade materials for air-film holes machining, and high quality air-film holes without hole wall recast layer and micro-cracks are processed through a large number of experiments to optimize machining technology and technological parameter. ? (2013) Trans Tech Publications, Switzerland.Accession Number: 20130415941285 -
Record 275 of
Title:Image super-resolution via double sparsity regularized manifold learning
Author(s):Lu, Xiaoqiang(1); Yuan, Yuan(1); Yan, Pingkun(1)Source: IEEE Transactions on Circuits and Systems for Video Technology Volume: 23 Issue: 12 DOI: 10.1109/TCSVT.2013.2244798 Published: December 2013Abstract:Over the past few years, high resolutions have been desirable or essential, e.g., in online video systems, and therefore, much has been done to achieve an image of higher resolution from the corresponding low-resolution ones. This procedure of recovering/rebuilding is called single-image super-resolution (SR). Performance of image SR has been significantly improved via methods of sparse coding. That is to say, the image frame patch can be sparse linear combinations of basis elements. However, most of these existing methods fail to consider the local geometrical structure in the space of the training data. To take this crucial issue into account, this paper proposes a method named double sparsity regularized manifold learning (DSRML). DSRML can preserve the properties of the aforementioned local geometrical structure by employing manifold learning, e.g., locally linear embedding. Based on a large amount of experimental results, DSRML is demonstrated to be more robust and more effective than previous efforts in the task of single-image SR. ? 2013 IEEE.Accession Number: 20141117450328 -
Record 276 of
Title:Study on adaptive modulation used in fading channels
Author(s):Xin, Wang(1,2); Wei, Gao(1); Zongxi, Song(2)Source: Applied Mechanics and Materials Volume: 303-306 Issue: DOI: 10.4028/www.scientific.net/AMM.303-306.2068 Published: 2013Abstract:Most of traditional modulation and coding techniques do not adapt to fading or nonlinear conditions. These non-adaptive methods require a fix-link margin to maintain acceptable performance when the channel quality is poor. Thus, these systems are effectively designed for the worst-case channel conditions, resulting in insufficient utilization of the full channel capacity. Adapting to signal fading allows the channel to be used more efficiently since the power rate can be adjusted to take advantage of favorable channel conditions. In this paper, we present a simplifiedmathematical model to calculate the probability of SER for any given constellation of M-QAM. This model plays an important role in designing spectrally efficient adaptive modulation over nonlinear mobile channels. Instantaneous spectral efficiency and its histogram distribution are found for linear and nonlinear channel cases. ? (2013) Trans Tech Publications, Switzerland.Accession Number: 20131116115690