2017
2017
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Record 37 of
Title:Passively mode-locked laser with an ultra-narrow spectral width
Author(s):Kues, Michael(1,2); Reimer, Christian(1); Wetzel, Benjamin(1,3); Roztocki, Piotr(4); Little, Brent E.(5); Chu, Sai T.(1); Hansson, Tobias(1); Viktorov, Evgeny A.(6); Moss, David J.(7); Morandotti, Roberto(1,6,8)Source: Nature Photonics Volume: 11 Issue: 3 DOI: 10.1038/nphoton.2016.271 Published: March 1, 2017Abstract:Most mode-locking techniques introduced in the past focused mainly on increasing the spectral bandwidth to achieve ultrashort, sub-picosecond-long coherent light pulses. By contrast, less importance seemed to be given to mode-locked lasers generating Fourier-Transform-limited nanosecond pulses, which feature the narrow spectral bandwidths required for applications in spectroscopy, the efficient excitation of molecules, sensing and quantum optics. Here, we demonstrate a passively mode-locked laser system that relies on simultaneous nested cavity filtering and cavity-enhanced nonlinear interactions within an integrated microring resonator. This allows us to produce optical pulses in the nanosecond regime (4.3 ns in duration), with an overall spectral bandwidth of 104.9 MHz-more than two orders of magnitude smaller than previous realizations. The very narrow bandwidth of our laser makes it possible to fully characterize its spectral properties in the radiofrequency domain using widely available GHz-bandwidth optoelectronic components. In turn, this characterization reveals the strong coherence of the generated pulse train.Accession Number: 20170503309096 -
Record 38 of
Title:The effect factors of the line of sight jitter
Author(s):Chang, Sansan(1); Yang, Hongtao(1); Liu, Guangsen(1); Gao, Bo(1); Guo, Yunzeng(1)Source: Proceedings - 9th International Conference on Intelligent Human-Machine Systems and Cybernetics, IHMSC 2017 Volume: 2 Issue: DOI: 10.1109/IHMSC.2017.168 Published: September 20, 2017Abstract:The stability precision is the key technical factor of optical-electro inertially stabilized platform. Combined with the mechanism of inertially stabilized platform system, the mathematical model of the pitch gimbal of inertially stabilized platform is established. The disturbance impacts of stability precision are analyzed and concluded in this paper. And the expression about how the disturbance source impact line of sight precision are deduced by the analysis of mathematical mode with classical engineering control algorithm. The analyses are validated by simulations and experiments, which may provide the reference for engineering application. ? 2017 IEEE.Accession Number: 20174704432658 -
Record 39 of
Title:A new compressive sensing video coding framework based on Gaussian mixture model
Author(s):Li, Xiangwei(1,2); Lan, Xuguang(1); Yang, Meng(1); Xue, Jianru(1); Zheng, Nanning(1)Source: Signal Processing: Image Communication Volume: 55 Issue: DOI: 10.1016/j.image.2017.03.009 Published: July 1, 2017Abstract:In this paper, we specifically design an efficient compressive sensing video (CSV) coding framework for the CSV system, by considering the distribution characteristics of the CSV frame. To explore the spatial redundancy of the CSV, the CSV frame is first divided into blocks and each block is modeled by a Gaussian mixture model (GMM), and then it is compressed by a product vector quantization. We further explore the temporal redundancy of the CSV by encoding the adjacent CSV frames by the differential pulse code modulation technique and the arithmetic encoding technique. Experiment results show that the proposed CSV coding solution maintains low coding complexity, which is required by the CSV system. Meanwhile, it achieves significant BD-PSNR improvement by about 7.13–11.41 dB (or equivalently 51.23–66.96% bitrate savings) compared with four existing video coding solutions, which also have low computational complexity and suit for the CSV system. ? 2017Accession Number: 20171403531810 -
Record 40 of
Title:A new lossless compression scheme for large aperture static imaging spectrometer
Author(s):Yu, Lu(1,2); Liu, Xuebin(1); Li, Hongbo(1); Yu, Tao(1); Hu, Bingliang(1)Source: 2017 International Conference on Circuits, Devices and Systems, ICCDS 2017 Volume: 2017-January Issue: DOI: 10.1109/ICCDS.2017.8120474 Published: November 27, 2017Abstract:In this paper, a novel method for the lossless compression of the interferometer hyperspectral instrument Large Aperture Static Imaging Spectrometer (LASIS) data is presented. This scheme rests upon the combination of data rearrangement and band ordering of LASIS three dimensional image and the recently presented CCSDS-123 lossless multispectral & Hyperspectral image compression standard. Firstly, the LASIS data is rearranged from the photo acquisition coordinate to the optical path difference (OPD) image coordinate by the rearrange approach to remove the interference information superimposed on the image. Then the OPD band is reordered according to the interferogram characteristic to improve the correlation between adjacent bands. Finally, the reordered OPD band data is processed using the CCSDS-123 standard. Several experiments were conducted to investigate the performance of the proposed compression scheme in the end. Experimental results suggest that this proposed compression scheme gives 31% higher compression ratio than using the standard alone. ? 2017 IEEE.Accession Number: 20181104903837 -
Record 41 of
Title:Integrated generation of high-dimensional entangled photon states and their coherent control
Author(s):Reimer, C.(1,2); Kues, M.(1); Roztocki, P.(1); Romero Cortés, L.(1); Sciara, S.(1,3); Wetzel, B.(1,4); Zhang, Y.(1); Cino, A.(3); Chu, S.T.(5); Little, B.E.(6); Moss, D.J.(7); Caspani, L.(8); Aza?a, J.(1); Morandotti, R.(1,9,10)Source: Optics InfoBase Conference Papers Volume: Part F66-FiO 2017 Issue: DOI: 10.1364/FIO.2017.FTh3E.2 Published: 2017Abstract:Exploiting a frequency-domain approach, we demonstrate the generation of highdimensional entangled quantum states with a Hilbert-space dimensionality larger than 100 from an on-chip nonlinear microcavity, and introduce a coherent control platform using standard telecommunications components. ? OSA 2017.Accession Number: 20174804480258 -
Record 42 of
Title:A new method for desiccant package quality check
Author(s):Fan, Yingchun(1,2); Zhou, Zuofeng(1,2); Yang, Hongtao(1,2); Cao, Jianzhong(1,2)Source: Advances in Intelligent Systems and Computing Volume: 541 Issue: DOI: 10.1007/978-3-319-49568-2_11 Published: 2017Abstract:The desiccant is widely used and plays an important role in the daily life and industrial manufacturing. Ironically its package quality check is still a challenging issue. In this paper we present a new method for desiccant package quality check. First, the package lie on the assembly line in arbitrarily direction corrected to vertical direction. Then the colicor information is used to distinguish the contaminated package. Finally, we combine the texture analysis and region growth to obtain the detection result. The experimental results show the effectiveness of the proposed method and the detection accuracy can achieve 92.85%. ? Springer International Publishing AG 2017.Accession Number: 20165303198447 -
Record 43 of
Title:Research on electromechanical resonance of two-axis tracking system
Author(s):Zhao, Zhi-Ming(1); Xue, Ying-Jie(1); Zeng, Shu-Qin(1); Li, Zhi-Guo(2)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 10256 Issue: DOI: 10.1117/12.2257210 Published: 2017Abstract:The multi-axes synchronous system about the spatial two-axis turntable is the key equipment for semi-physical simulation and test in aerospace. In this paper, the whole structure design of the turntable is created by using Solidworks, then putting the three-dimensional solid model into ANSYS to build the finite element model. The software ANSYS is used to do the simulation about the static and dynamic analysis of two-axis turntable. Based on the modal analysis, we can forecast the inherent frequencies and the mode of vibration during the launch conditions which is very important to the design and safety of the structure. ? 2017 SPIE.Accession Number: 20171703607645 -
Record 44 of
Title:An adaptive correction algorithm for non-uniform illumination panoramic images based on the improved bilateral gamma function
Author(s):Wang, Dianwei(1); Yan, Weichao(1); Zhu, Tingge(1); Xie, Yongjun(2); Song, Haijun(2); Hu, Xinrong(2)Source: DICTA 2017 - 2017 International Conference on Digital Image Computing: Techniques and Applications Volume: 2017-December Issue: DOI: 10.1109/DICTA.2017.8227404 Published: December 19, 2017Abstract:In this work we discuss an efficient strategy for reducing the negative impact of non-uniform illumination to panoramic image quality by proposing an adaptive correction algorithm based on the improved Bilateral Gamma function. Firstly the illumination component is extracted by a fast image guided filter. Then an improved bilateral Gamma function fed by the distribution characteristics of illumination is modelled. Finally the non-uniform illumination panoramic image is adjusted adaptively by the devised algorithm, which can increase the intensity value at low illumination regions, and vice versa in the high illumination regions in a panoramic image. Experimental results show that the proposed algorithm can reduce the negative impact caused by the non-uniformity of illumination conditions and enhance the visual quality across different imaging scenarios. ? 2017 IEEE.Accession Number: 20182405311056 -
Record 45 of
Title:Sensorless control of three-phase permanent magnet synchronous motor based on fundamental wave mathematical model
Author(s):Xing, Shi Chen(1); Chen, Wang(2)Source: Proceedings - 2017 2nd International Conference on Cybernetics, Robotics and Control, CRC 2017 Volume: 2018-January Issue: DOI: 10.1109/CRC.2017.29 Published: July 2, 2017Abstract:In the case of vector control using magnetic field orientation, in order to achieve high performance three-phase PMSM (Permanent Magnet Synchronous Motor) control system, generally we need to obtain an accurate rotor position and speed information, but the use of mechanical sensors will increase the use of system cost, size and quality, and the use of the environment has a more stringent requirements. Sensorless control technology detects the motor winding and focusing on the relevant electrical signals and uses a certain control algorithm to achieve the rotor position and speed estimates. It represents the three-phase PMSM control system development trend. This paper focuses on the sensorless control of three-phase permanent magnet synchronous motor based on the fundamental wave mathematical model. This method relies on the rotational speed-related quantities (such as the generated back electromotive force) in the three-phase PMSM fundamental excitation mathematical model for rotor position and velocity. It is estimated that since the signal-to-noise ratio of the useful signal is low when the motor is running at zero speed and very low speed, it is usually difficult to extract. Thus, ultimately, dependence on the fundamental excitation ultimately results in failure of rotor position and velocity detection at zero speed and low speed. At present, the commonly used algorithms include sliding mode observer algorithm, model reference adaptive control algorithm and extended Kalman filter algorithm. In this paper, the sliding mode observer algorithm is analyzed and modeled. This paper firstly introduces the basic concept of sliding mode control, and then analyzes the commonly used traditional sliding mode observer algorithm and the sliding mode observer algorithm in synchronous rotating coordinate system. Secondly, the permanent magnet synchronous motor control system based on two algorithms is simulated in Matlab2016 / Simulink environment. The response curves of the two control system simulation models under the condition of external disturbance are analyzed.We can get a conclusion that by selecting the appropriate controller parameters, SMO (sliding mode observer)-based three-phase PMSM sensorless control technology can meet the needs of the actual motor control performance. ? 2017 IEEE.Accession Number: 20182205249292 -
Record 46 of
Title:Feature extraction based on tensor modelling for classification methods
Author(s):Yan, Ronghua(1,3); Peng, Jinye(1,2); Ma, Dongmei(4); Wen, Desheng(3); Dong, Yingdi(5)Source: Conference Proceedings - 2017 International Conference on the Frontiers and Advances in Data Science, FADS 2017 Volume: 2018-January Issue: DOI: 10.1109/FADS.2017.8253205 Published: July 1, 2017Abstract:Both spatial and spectral information is used when a hyperspectral image is modeled as a tensor. However, this model does not consider both the class and within-class information about the spectral features of ground objects. This means that further improving classification is very difficult. The authors propose that class information, within-class information, and pixels are selected to model a third-order tensor. The most important advantage of the proposed method is that all the pixels of one class are mapped to the same coefficient vector. Therefore, the within-class scatter is minimized, and the classification is improved when compared to the previous methods. ? 2017 IEEE.Accession Number: 20183005592134 -
Record 47 of
Title:Model in frequency-domain identification of a fast steering mirror system based on levenberg-marquardt algorithm
Author(s):Peng, Chen(1); Yanbing, Liang(2)Source: Proceedings - 2017 2nd International Conference on Cybernetics, Robotics and Control, CRC 2017 Volume: 2018-January Issue: DOI: 10.1109/CRC.2017.10 Published: July 2, 2017Abstract:A method for frequency-domain identification of a fast steering mirror system is provided. The method firstly uses swept sine as dynamic excitation signal to obtain the frequency characteristics of controlled object and frequency response data by dynamic signal analyzer Agilent 35670A. Then the paper uses data pre-processed to analyze magnitude-phase characteristics based on FFT (Fast Fourier Fransform). The error of FFT calculation is relative major. To obtain the frequency characteristics approaching to real system, windowing and Sample Hold is introduced to modify magnitude-phase characteristics. For non-parametric frequency characteristics curve of the system, in combination of Levenberg-Marquardt nonlinear least squares curve fitting and transfer function model based on dynamic mechanism modelling, this paper implements curve fitting for low frequency band with frequency characteristics. With this method, the frequency characteristics of complex system can be converted to accurate transfer function. Levenberg-Marquardt algorithm providing the theoretical support for parameterizing BODE diagram is an optimization strategy. The optimization strategy improves the matching degree between actual system and model system in process of modeling and it is provided for the compensation of the influence which is from the temperature shift and measurement error of components. The paper provides a theoretical foundation for building a more complex electro-optical tracking system. ? 2017 IEEE.Accession Number: 20182205249426 -
Record 48 of
Title:Demonstration of Real-Time Modulation-Adaptable Transmitter
Author(s):Yan, Shuangyi(1); Beldachi, Arash Farhadi(1); Qian, Fengchen(1,2); Kondepu, Koteswararao(1); Yan, Yan(1); Jackson, Chris(1); Nejabati, Reza(1); Simeonidou, DImitra(1)Source: European Conference on Optical Communication, ECOC Volume: 2017-September Issue: DOI: 10.1109/ECOC.2017.8346029 Published: July 2, 2017Abstract:We demonstrate a 26 Gbaud real-time quick-reconfigurable 16QAM/QPSK-adaptable transmitter. The modulation format can be switched in less than a second by an RMAT agent. The FPGA-driven reconfigurable transmitter can work as a generic edge-node interface for traffic aggregation. ? 2017 IEEE.Accession Number: 20182105211474