2017
2017
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Record 61 of
Title:Improved multiple circular array configuration for sparse aperture optical imaging systems
Author(s):Liu, Aimin(1,2); Gao, Limin(1); Xiao, Maosen(1)Source: Optical Engineering Volume: 56 Issue: 7 DOI: 10.1117/1.OE.56.7.073109 Published: July 1, 2017Abstract:An improved multiple circular array (MCA) configuration is proposed for sparse aperture (SA) optical imaging systems. Using genetic algorithms, the practical cutoff frequency (PCOF), based on the modulation transfer function for the array, is selected as the fitness function. Moreover, the parameters, such as diameters of aperture sets, spacing between the aperture sets, and relative rotation angles between aperture sets on different concentric circles, are calculated. Improved MCA configurations, with aperture numbers of 6, 9, 12, 10, 15, 11, and 13, are given. Golay arrays, MCAs, a single annular aperture, and improved arrays with the same fill factor are compared. The results show that the improved array has highest PCOF of all the SA arrays, smoother coverage in Fourier space, and better midfrequency contrast than MCAs. Consequently, the improved array is a promising aperture configuration that can approximate a single annular aperture. ? 2017 Society of Photo-Optical Instrumentation Engineers (SPIE).Accession Number: 20173104012450 -
Record 62 of
Title:Visual saliency detection based on region contrast and guided filter
Author(s):Liu, Liqiang(1,2); Cao, Jianzhong(1); Niu, Yuefeng(1,2); Guo, Huinan(1)Source: 2017 2nd IEEE International Conference on Computational Intelligence and Applications, ICCIA 2017 Volume: 2017-January Issue: DOI: 10.1109/CIAPP.2017.8167232 Published: December 4, 2017Abstract:The main challenge of previous saliency detection method is the low quality of obtained saliency map which missed the edge and texture information easily. So it cannot reflect the integrated image salient information. Considering this problem, we propose a novel saliency measure method which combine region contrast and fast guided filter. This method utilizes region contrast method to obtain initial saliency maps. Then we optimize the saliency maps by using the fast guided filter. Extensive experimental results on natural image show the effectiveness of the proposed method. One aspect, the obtained final saliency maps have obvious advantages in dealing with the texture and weakening the inconsequential region. Another aspect, evaluation on the two databases validates that our method achieves superior results and outperforms compared previous approach in both precision and recall. ? 2017 IEEE.Accession Number: 20181104902376 -
Record 63 of
Title:Robust control of boost converter
Author(s):Qi, Lijie(1,2); Xiao, Maosen(1)Source: Proceedings - 2017 2nd International Conference on Cybernetics, Robotics and Control, CRC 2017 Volume: 2018-January Issue: DOI: 10.1109/CRC.2017.17 Published: July 2, 2017Abstract:In recent years, high-performance DC-DC converter is a key research direction in the fields of power design. This paper takes the Boost-converter as an example to construct the mathematical model. Besides, it also applies several control strategies which includes PID control based on genetic algorithm, sliding mode control algorithm and so on to the design of DC-DC converter. Finally, we analyzed the simulation results. ? 2017 IEEE.Accession Number: 20182205249318 -
Record 64 of
Title:Roles of palladium particles in enhancing the electrochemical migration resistance of sintered nano-silver paste as a bonding material
Author(s):Wang, Di(1); Mei, Yun-Hui(1,2); Xie, Haining(3); Zhang, Kun(3); Siow, Kim S.(4); Li, Xin(1); Lu, Guo-Quan(5)Source: Materials Letters Volume: 206 Issue: DOI: 10.1016/j.matlet.2017.06.066 Published: November 1, 2017Abstract:The inhibition effect and mechanism of adding palladium particles to nano-silver paste on the migration of silver in high temperature is reported. The electrochemical migration (ECM) tests showed that silver migration was significantly delayed by the addition of palladium. The roles of different compositions, e.g., PdO, in enhancing the ECM resistance of silver were studied experimentally. We found Ag-Pd alloy? ? 2017 Elsevier B.V.Accession Number: 20172603860667 -
Record 65 of
Title:Development of the electronics system prototype of the high-speed camera
Author(s):Zheng, Yang(1,2); Li, Ruimin(1,2); Song, Zongxi(1)Source: Proceedings of 2017 IEEE 3rd Information Technology and Mechatronics Engineering Conference, ITOEC 2017 Volume: 2017-January Issue: DOI: 10.1109/ITOEC.2017.8122537 Published: November 27, 2017Abstract:The high-speed camera is an imaging device that records a particular transient state or all of the high-speed processes. It can accurately record the transient process of the high-speed target in real time and thus allow us to achieve the purpose of analysis of high-speed process through the slow motion playback. So the high-speed camera becomes an important tool for the study of the transient phenomena. This paper presents the development of a high-speed imaging system, which was build based upon a CMOS (Complementary Metal Oxide Semiconductor) image sensor and a high density FPGA (Field Programmable Gate Array) and USB 3.0 (Universal Serial Bus 3.0). In this paper, the design methodology and the electronics system architecture are briefly discussed. Besides, the designs and implements are particularly depicted. Finally the experimental verification shows the correlated results. The system has the advantage of high frame rate, high resolution, high performance and flexibility. ? 2017 IEEE.Accession Number: 20181104893549 -
Record 66 of
Title:Automatic Bifurcation angle calculation in intravascular optical coherence tomography images
Author(s):Cao, Yihui(1); Liu, Chao(2); Jin, Qinhua(3); Chen, Yundai(3); Yin, Qinye(4); Li, Jianan(1); Zhao, Wei(1)Source: 2017 2nd International Conference on Image, Vision and Computing, ICIVC 2017 Volume: Issue: DOI: 10.1109/ICIVC.2017.7984636 Published: July 18, 2017Abstract:This Bifurcation angle (BA) has important predictive value for outcome of percutaneous coronary intervention (PCI) and the selection of interventional instruments and strategies. Therefore, bifurcation angle requires precise measurements. Intravascular optical coherence tomography (IVOCT) is the state-of-the-art high-resolution imaging modality which provides the possibility of the accurate measurements of bifurcation angle. However, to the best of our knowledge, there is no published work for calculating bifurcation angle based on IVOCT images. Inspired by previous studies on carotid bifurcation angle measurement based on black-blood magnetic resonance imaging, we creatively proposed a fully automatic computing method for bifurcation angle based on the detection of centers of the main vessel and side branch. Then, the detected center points are projected into a fitting plane by minimizing the reconstruction error to calculate the bifurcation angle. Finally, the 3D reconstructed main vessel and side branch demonstrate the proposed bifurcation angle calculation method is accessible. ? 2017 IEEE.Accession Number: 20173804169338 -
Record 67 of
Title:Superfluidicity in an optical lattice with a PT symmetric defect
Author(s):Zhang, Lingxuan(1,2,3); Zhang, Wenfu(3); Ge, Li(1,2)Source: Optics InfoBase Conference Papers Volume: Part F66-FiO 2017 Issue: DOI: 10.1364/FIO.2017.JTu3A.89 Published: 2017Abstract:We consider a nonlinear waveguide array with a PT symmetric defect at the center of a parabolic potential. The oscillations of a coherent state persist without dissipation, if its velocity is below a critical value. ? OSA 2017.Accession Number: 20174804480176 -
Record 68 of
Title:Optical system design of lunar rover navigation camera
Author(s):Wang, Hu(1); Liu, Jie(1); Liu, Meiying(1,2); Xue, Yaoke(1); Liu, Yang(1); Lin, Shangmin(1); Zhang, Xibin(1); Wang, Feng(1); Pang, Shuxia(1,2)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 10463 Issue: DOI: 10.1117/12.2285166 Published: 2017Abstract:The optical system of lunar rover navigation camera has a direct influence on imaging quality, and an indirect influence on the programming of march forward of lunar rover. One type of lunar rover navigation camera optical system with the symmetrical structure was introduced. It also set up the suitable position of stop to achieve the relative distortion lower than 0.053 percent under the 60 degrees wide field-of-view. It applied the hyperfocal distance principle to achieve the clear imaging from 0.5 meter to infinity. The modulation transfer function is close to diffraction limit at the Nyquist frequency (at standard object distance). Considering the complicate environment of lunar surface and the demand of exploration, it selected the appropriate work spectral coverage and was cooperated by the irradiation reinforce. As a result, it can bear 1×104 Rad (Si) space irradiation and is capable of keeping working normally in the severe environment with its temperature varying from-60°C to + 90°C. ? 2017 SPIE.Accession Number: 20180304654860 -
Record 69 of
Title:Analysis and compensation of disturbance for small inertial stabilized line-of-sight system
Author(s):Meng, Zhang(1,2); Junfeng, Han(2)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 10256 Issue: DOI: 10.1117/12.2257355 Published: 2017Abstract:One of the main factors that affect the performance of stabilized Line-of-Sight (LOS) control system is disturbance torque. Firstly, the transfer function between disturbance torque and angular velocity of LOS is given by establishing the system dynamics model. Secondly, we investigate the characteristics of disturbance torque for small inertial Line-of-Sight control system. Thirdly, an application of disturbance observer is presented to compensate for disturbance, such as friction and mass imbalance. In this paper, consider only friction. Simulation is made by using the friction model output as disturbance input. In the course of Matlab simulation, the compensation by using disturbance observer improves the overall stabilization performance of the system. The RMS value of the velocity error has decreased to 10%. ? 2017 SPIE.Accession Number: 20171703607527 -
Record 70 of
Title:Multiple Targets Real-time Intersection of Optic-electronic Theodolite
Author(s):Wu, Jing(1,2); Su, Xiu-Qin(1); Guo, Min(1)Source: Guangzi Xuebao/Acta Photonica Sinica Volume: 46 Issue: 4 DOI: 10.3788/gzxb20174604.0411003 Published: April 1, 2017Abstract:In order to achieve the real-time calculating about the flight trajectories of the multiple targets and guiding the equipment to track the targets, a real-time multi-target intersection method was proposed. Such method is based on the characteristic of target movement and the inherent characteristic of optic-electronic theodolite tracking measurement. This algorithm can achieve the goals of sorting homologous measurement data and eliminating the false target trajectory, and finally get the true target trajectory. The algorithm is applied to the optic-electronic theodolite measuring system which is under the condition of target N≤3 and communication cycle being 50ms. The experiment results show that the method can guide the measuring equipment to track accurately, stably and in real time. ? 2017, Science Press. All right reserved.Accession Number: 20172803903573 -
Record 71 of
Title:Video summarization with attention-based encoder-decoder networks
Author(s):Ji, Zhong(1); Xiong, Kailin(1); Pang, Yanwei(1); Li, Xuelong(2)Source: arXiv Volume: Issue: DOI: Published: August 30, 2017Abstract:This paper addresses the problem of supervised video summarization by formulating it as a sequence-to-sequence learning problem, where the input is a sequence of original video frames, the output is a keyshot sequence. Our key idea is to learn a deep summarization network with attention mechanism to mimic the way of selecting the keyshots of human. To this end, we propose a novel video summarization framework named Attentive encoder-decoder networks for Video Summarization (AVS), in which the encoder uses a Bidirectional Long Short-Term Memory (BiLSTM) to encode the contextual information among the input video frames. As for the decoder, two attention-based LSTM networks are explored by using additive and multiplicative objective functions, respectively. Extensive experiments are conducted on two video summarization benchmark datasets, i.e., SumMe, and TVSum. The results demonstrate the superiority of the proposed AVS-based approaches against the state-of-the-art approaches, with remarkable improvements from 0.8% to 3% on two datasets, respectively. Copyright ? 2017, The Authors. All rights reserved.Accession Number: 20200329096 -
Record 72 of
Title:Nuclear Norm-Based 2DLPP for Image Classification
Author(s):Lu, Yuwu(1,2); Yuan, Chun(1,2); Lai, Zhihui(3); Li, Xuelong(4); Wong, Wai Keung(5); Zhang, David(6)Source: IEEE Transactions on Multimedia Volume: 19 Issue: 11 DOI: 10.1109/TMM.2017.2703130 Published: November 2017Abstract:Two-dimensional locality preserving projections (2DLPP) that use 2D image representation in preserving projection learning can preserve the intrinsic manifold structure and local information of data. However, 2DLPP is based on the Euclidean distance, which is sensitive to noise and outliers in data. In this paper, we propose a novel locality preserving projection method called nuclear norm-based two-dimensional locality preserving projections (NN-2DLPP). First, NN-2DLPP recovers the noisy data matrix through low-rank learning. Second, noise in data is removed and the learned clean data points are projected on a new subspace. Without the disturbance of noise, data points belonging to the same class are kept as close to each other as possible in the new projective subspace. Experimental results on six public image databases with face recognition, object classification, and handwritten digit recognition tasks demonstrated the effectiveness of the proposed method. ? 1999-2012 IEEE.Accession Number: 20174404314074