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WRI International Conference on Communications and Mobile Computing, CMC

作者： Jianguo Liu Zhenbing Liu Guoyou Wang Key Laboratory of Education Ministry for Image Processing and Intelligent Control State Key Laboratory of Multispectral Information Processing Technologies Institute of Pattern Recognition and Artificial Intelligence Huazhong University of Science and Technology Wuhan China

Convolution is an important and useful operation in the fields of digital signal processing. In this paper, based on the previous work of performing discrete Fourier transform (DFT) via linear sums of discrete moments, we have made development to eliminate multiplications in discrete Fourier transforms by performing appropriate bit operations and shift operations in binary system, which can be implemented by integer additions of fixed points; then using the convolution theorem with the DFT, we compute the convolution with two DFTs, a point-by-point product, and an inverse DFT. Our algorithm involves fewer multiplications and can deal with arbitrary length signals.

关键词： Convolution Signal processing algorithms Discrete Fourier transforms Very large scale integration Algorithm design and analysis Laboratories Educational technology Digital signal processing Mobile communication Mobile computing

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Investigation of timing resolution and energy resolution for SiPM/PET detectors using the silicon flexible optical material

Investigation of timing resolution and energy resolution for...

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IEEE Symposium on Nuclear science (NSS/MIC)

作者： Jun Zhu Wensheng Xu Ming Niu Daoming Xi Xinyu Zhang Qingguo Xie Department of Biomedical Engineering Huazhong University of Science and Technology Wuhan China Wuhan National Laboratory of Optoelectronics Wuhan China School of Mechanical Electronic and Control Engineering Beijing Jiaotong University Beijing China Institute for Pattern Recognition and Artificial Intelligence Huazhong University of Science and Technology Wuhan China

Silicon photomultipliers (SiPMs) attract extensive attentions for detecting optical photons in high energy physics and medical imaging due to its high gain, high photon detection efficiency (PDE), low operation voltage and fast timing response. We use a binary optical element (BOE) made of the silicon flexible optical material to transform the incident light intensity expressed as Gaussian distribution into uniform in space, making the incident photons be detected by the SiPM evenly. In this way, we can make full use of all cells of the SiPM, and more cells operating means more photons being detected for a certain pulse, which can increase the count rate of the incident photons and therefore improve the detection efficiency of the SiPM. Also, by comparing the outputs of the SiPM in different light intensity inputs, we can obtain the best light intensity fit for the SiPM along with the suitable scintillator and surface treatment for the positron emission tomography (PET) imaging based on the SiPM. In our experiments, we use the laser pulse as the SiPM input, whose light intensity can be expressed as Gaussian distribution in space, and then compare the readouts of the SiPM with and without the BOE. As expected, by using the BOE, the timing resolution and energy resolution of the SiPM are better than those without using it for some certain light intensity.

关键词： Energy resolution Timing Positron emission tomography Silicon Optical materials Biomedical optical imaging Gaussian distribution Photomultipliers Optical detectors Biomedical imaging

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Dynamic inversion based satellite attitude fault tolerant control system with reaction wheel fault

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Zhongnan Daxue Xuebao (Ziran Kexue Ban)/Journal of Central South University (science and technology) 2009年第SUPPL. 1期40卷 191-199页

作者： Tian, Ke-Feng Li, Zhi-Bin Beijing Institute of Control Engineering Beijing 100190 China National Key Laboratory of Science and Technology on Space Intelligent Control Beijing 100190 China

The design of on-line fault detection, identification and reconfiguration(FDIR) for three-axis-stabilized satellite attitude control system with reaction wheel(RW) fault was presented. Firstly, the fault pattern of RW was analyzed and a parameterized description for fault was established based on its dynamic model. Then, local FDI was used to diagnose the fault of RW by parameter identification. Based on the method of dynamic inversion, by introducing the model of reaction wheel, the reconfigurable controller was obtained to deal with RW fault. Finally, numerical simulation results with three fault patterns demonstrate that the proposed approach is effective and feasible.

关键词： Wheels

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Low-temperature (< 100°C) poly-si thin film fabrication on glass

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Chinese Physics Letters 2009年第1期26卷

作者： Wang, Cheng-Long Fan, Duo-Wang Sun, Shuo Zhang, Fu-Jia Liu, Hong-Zhong National Engineering Research Center for Technology and Equipment of Green Coating Lanzhou Jiaotong University Lanzhou 730070 China MOE Key Lab of Opto-electronic Technology and Intelligence Control Lanzhou Jiaotong University Lanzhou 730070 China School of Physics Science and Technology Lanzhou University Lanzhou 730000 China State Key Laboratory for Manufacturing Systems Engineering Xi'An Jiaotong University Xi'an 710049 China

Polycrystalline silicon (poly-Si) thin-film is fabricated on Al-coated planar glass substrates at the temperature below 100 °C, using aluminium-induced crystallized (AIC) amorphous silicon (a-Si) deposited by dc-magnetron sputtering under an electric field. The properties of NA poly-Si films (AIC of dc-magnetron sputtered silicon non-annealing) are characterized by Raman spectroscopy and x-ray diffraction (XRD) spectroscopy. A narrow and symmetrical Raman peak at a wave number of about 521 cm-1 is observed for samples, showing that the films are fully crystallized. XRD spectra reveal that the films are preferentially (111) oriented. Furthermore, the XRD spectrum of the sample prepared without electric field does not show any XRD peaks for poly-Si, which only appears at about 38° for Al (111) orientation. It is indicated that the electric field plays an important role in crystallization of poly-Si during the dc-magnetron sputtering. Thus, high quality poly-Si film can be obtained at low temperature and separate post-deposition step of AIC of a-silicon can be avoided. © 2009 Chinese Physical Society and IOP Publishing Ltd.

关键词： Electric fields

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Needle segmentation using 3D quick randomized hough transform

Needle segmentation using 3D quick randomized hough transfor...

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1st International Conference on Intelligent Networks and Intelligent Systems, ICINIS 2008

作者： Qiu, Wu Ding, Mingyue Yuchi, Ming Institute for Pattern Recognition and Artificial Intelligence Image Processing and Intelligence Control Key Laboratory of Education Ministry of China Huazhong University of Science and Technology Wuhan Hubei China Department of Biomedical Engineering School of Life Science and Technology Huazhong University of Science and Technology Wuhan Hubei China

ISBN: (纸本)9780769533919

A quick 3D needle segmentation algorithm for 3D US data is described in this paper. The algorithm includes the 3D Quick Randomized Hough Transform (3DGHT), which is based on the 3D Randomized Hough Transform and coarse-fine searching strategy. We tested it with water phantom. The results show that our algorithm works well in 3D US images with angular deviation less than 1 and position deviation less than 1mm, and the computational time of segmentation with 35MB data is within 1s. © 2008 IEEE.

关键词： Hough transforms

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High performance word level sequential and parallel coding methods and architectures for bit plane coding

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science in China(Series F) 2008年第4期51卷 337-351页

作者： XIONG ChengYi TIAN JinWen LIU Jian College of Electronic Information Engineering South-Central University for Nationalities Wuhan 430074 China Institute of Pattern Recognition & Artificial Intelligence Key Laboratory of Education Ministry for Image Processing and Intelligent Control Huazhong University of Science & Technology Wuhan 430074 China

This paper introduced a novel high performance algorithm and VLSI architectures for achieving bit plane coding （BPC） in word level sequential and parallel mode. The proposed BPC algorithm adopts the techniques of coding pass prediction and parallel ＆ pipeline to reduce the number of accessing memory and to increase the ability of concurrently processing of the system, where all the coefficient bits of a code block could be coded by only one scan. A new parallel bit plane architecture （PA） was proposed to achieve word-level sequential coding. Moreover, an efficient high-speed architecture （HA） was presented to achieve multi-word parallel coding. Compared to the state of the art, the proposed PA could reduce the hardware cost more efficiently, though the throughput retains one coefficient coded per clock. While the proposed HA could perform coding for 4 coefficients belonging to a stripe column at one intra-clock cycle, so that coding for an NxN code-block could be completed in approximate N2/4 intra-clock cycles. Theoretical analysis and experimental results demonstrate that the proposed designs have high throughput rate with good performance in terms of speedup to cost, which can be good alternatives for low power applications.

关键词： bit plane coding high performance word-level sequential multi-word parallel

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An improved landweber method for restoration of a aero-optically degraded images

An improved landweber method for restoration of a aero-optic...

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International Conference on Computer science and Software Engineering, CSSE 2008

作者： Wenxia, Yang Chao, Cai Mingyue, Ding Chengping, Zhou Key Laboratory for Image Processing and Intelligence Control of the Ministry of Education Institute of IPRAI Huazhong University of Science and Technology Wuhan 430074 China Department of Mathematics Wuhan University of Technology Wuhan 430070 China

ISBN: (纸本)9780769533360

Aero-optic effects cause distortions, including blurring, vibration, deformation and spatial shifting, of the objects in the image obtained by the infra-red sensor. Contributions of this paper are in the following two aspects. First, the correctness of the theoretical point spread function (PSF) representing the aero-optic effects, which had been derived in our previous research, is validated experimentally. Second, in order to restore the aero-optically degraded images, an improved Landweber iteration method is proposed, where, instead of being fixed, the relaxation factor is updated adaptively at each iteration. Experiments have been carried out and results demonstrate that the proposed method introduces improved restoration results with better convergence. © 2008 IEEE.

关键词： Image reconstruction

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Method of boundary extraction based on schrödinger equation 21

Method of boundary extraction based on schrödinger equation

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2008 21st ISPRS International Congress for Photogrammetry and Remote Sensing

作者： Lou, Liantang Zhan, Xin Fu, Zhongliang Ding, Mingyue School of Remote Sensing and Information Engineering Wuhan University Wuhan430072 China School of Science Wuhan Institute of Technology Wuhan430073 China Institute for Pattern Recognition and Artificial Intelligence Key Laboratory of Education Ministry for Image Processing and Intelligent Control Huazhong University of Science and Technology Wuhan430074 China

To overcome the main drawbacks of global minimal for active contour models (L. D. Cohen and Ron Kimmel) that the contour is only extracted partially for low SNR images, Method of boundary extraction based on Schrödinger Equation is proposed. Our Method is based on computing the numerical solutions of initial value problem for second order nonlinear Schrödinger equation by using discrete Fourier Transformation. Schrödinger transformation of image is first given. We compute the probability P(b,a) that a particle moves from a point a to another point b according to I-Type Schrödinger transformation of image and obtain boundary of object by using quantum contour model.

关键词： Initial value problems

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Effect of ambient temperature on star sensor measurement accuracy

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Guangdian Gongcheng/Opto-Electronic Engineering 2008年第12期35卷 40-44页

作者： Liu, Hai-Bo Tan, Ji-Chun Hao, Yun-Cai Jia, Hui Tan, Wei Yang, Jian-Kun Institute of Technique Physics College of Science School of National University of Defense Technology Changsha 410073 China National Laboratory of Space Intelligent Control Beijing Aerospace Automatic Control Institute Beijing 100080 China

Measurement accuracy of star sensor is restricted by ambient temperature. This paper describes an effective approach to analyze thermal effects in optical systems of star sensor. The star position errors, which are caused by thermo-optic effects, are calculated in an optical system of middle-precision star sensor. The results show that the star position errors are not remarkable near field angle 0°. And material matching is an effective measure in reducing the star position errors caused by changes of ambient temperature. After thermal compensation design, the maximal error is only 0.02″ when the ambient temperature changes from -20°C to 60°C, which is about 1/7 of the original optical system's maximal error.

关键词： Star position error Star sensor Thermal design Thermal-optical analysis

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Modular design of adaptive controller for strict-feedback stochastic nonlinear systems with uncertain Wiener noise

Modular design of adaptive controller for strict-feedback st...

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International Conference on control, Automation, Robotics and Vision (ICARCV)

作者： Jun Wang Tao Cai Yu Kang Key Laboratory of Machine Vision and Intelligence Control Technology Hefei University Hefei China Department of Automation University of Science and Technology Hefei China

In this paper, a modular approach is proposed for a class of strict-feedback stochastic nonlinear systems with uncertain Wiener noises and constant unknown parameters. Both the adaptive Backstepping procedure and input-to-state stable(ISS) controller of global stabilization in probability are designed to guarantee that the system states are bounded and has adaptive stabilization while the covariance of Wiener noises is uncertain. According to Swapping technique, we develop two filters and convert dynamic parametric models into static ones to which the gradient update law is designed.

关键词： Programmable control Adaptive control Nonlinear control systems control systems Stochastic systems Stochastic resonance Nonlinear systems Backstepping Filters Parametric statistics

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