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Development and application of reflective intensity-modulated fiber optic sensing technique for displacement measurement

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Guangxue Jishu/Optical Technique 2005年第SUPPL.期31卷 342-344+349页

作者： Li, Hai-Yan Pu, Zhao-Bang Ge, Wen-Tao Department of Automatic Measurement and Control Harbin Institute of Technology Harbin 150001 China Department of Control Science and Engineering Harbin Institute of Technology Harbin 150001 China

For its unique merits, the reflective intensity-modulated fiber-optic sensing technique was widely applied in displacement detection and became research hotspot. However, the stability of light source, the disturbance of environment and the reflectivity variation of the measured surface had effects on the merchandising process. The current work for us to do was to find out some technique scheme suitable for the product merchandising. Thus the fiber-optic sensing technique could be used more widely in national defence and economic construction. The working principle of reflective intensity-modulated fiber optic sensor was presented. And the latest research findings and the application of it in displacement detection were also given.

关键词： Displacement detection Fiber optic sensing Intensity-modulated

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Closed loop control of a zoom lens system

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Guangdian Gongcheng/Opto-Electronic engineering 2005年第1期32卷 20-22+30页

作者： Bai, Gui-Zhen Mei, Xiao-Rong Zhang, Hua Dept. of Control Science and Eng. Harbin Inst. of Technology Harbin 150001 China

In view of the features and technical demands of mechanical unit in a zoom lens system, a closed-loop control scheme is adopted. The controller is designed by using two methods, i.e. a Dynamic Matrix control (DMC) algorithm and a linear cascade compensator. Under the conditions of both parameter variation and external disturbance not big, the performances of both methods are approximate, but the control method with linear compensator is always preferentially selected for its simplicity and maturity. The performances of these two methods are different when object parameter variation is big and a bigger disturbance is suffered: when time constant increases by one factor the maximum overshooting of the linear system varies from 8% to 21% and maximum overshooting of the dynamic matrix method varies from 6% to 9%. With the action of ramp disturbance, the error of the linear system is proportional to time and the error of the dynamic matrix method is 0.002. So when both object parameter variation and disturbance variations are big, the dynamic matrix method should be adopted. It can make the system have good robustness both in dynamic performance and homeostatic error.

关键词： Closed loop control Dynamic matrix control Zoom control Zoom lens

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Wavelet-based Kalman filtering for ring laser gyro denoising

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Guangdian Gongcheng/Opto-Electronic engineering 2005年第5期32卷 31-34页

作者： Gao, Yu-Kai Deng, Zheng-Long Department of Control Science and Engineering Harbin Institute of Technology Harbin 150001 China

According to the properties of non-stationary and non-normal distribution of random wandering drift in ring laser gyro (RLG), it is difficult to eliminate the noise by traditional method. A wavelet-based Kalman filter is employed based on conventional Kalman filtering. The method not only has the characters of multi-resolution analysis in wavelet domain and removing the properties of self-similarity, but also maintains linear unbiased and minimum error variance estimation of Kalman filtering for the unknown signal. Thus real-time multi-size decomposition and optimal estimation for random wandering noise can be realized. Practical measurement of RLG zero-biased signals after denoising show that standard error of random wandering drift has been reduced by 10.3% with wavelet-based Kalman filter. The denoising effect is better than traditional Kalman filter.

关键词： Kalman filtering Ring laser gyro Signal-noise ratio Wavelet transformation

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Novel contour extraction algorithm for a moving target based on image fusion

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Guangdianzi Jiguang/Journal of Optoelectronics Laser 2005年第8期16卷 973-977页

作者： Zhao, Peng Cao, Jun Pu, Zhao-Bang Zhang, Tian-Wen Department of Automation Measurement and Control Harbin Institute of Technology Harbin 150001 China Mechanic and Electronic Institute Northeast Forestry University Harbin 150040 China Department of Computer Science and Engineering Harbin Institute of Technology Harbin 150001 China

A contour extraction algorithm for a moving target is proposed. This algorithm consists of three steps. Firstly, motion segmentation is applied respectively to infrared and visible image sequences to get an initial contour of a moving target. Secondly, a dynamic contour is applied to make the initial contour converge to the target's contour. Finally, two novel image fusions are applied. The first fusion minimizes L2 norm's square of the difference of control point vectors in two modal images without image registration. The second fusion is realized by the modified differential coupling with image registration. Contrasting detection experiments indicate the second fusion is better. Meanwhile, a fast iteration algorithm of dynamic contour based on the Newmark method is devised. A contrasting experiment indicates its iteration time for stable convergence decreases by 21.01% compared with the Wilson-θ method.

关键词： Object recognition

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Ultrasound Image Segmentation Based on the Early Vision Model and Watershed Transform

Ultrasound Image Segmentation Based on the Early Vision Mode...

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IEEE inst.umentation and Measurement technology Conference

作者： Rong Lu Yi Shen Qiang Wang Dandan Li Department of Control Science and Engineering Harbin Institute of Technology Harbin China

Image segmentation is one of the basic steps for ultrasound image analysis and medical diagnosis. However, due to the intrinsic noisy nature, it remains to be a very difficult problem. A novel segmentation method based on watershed transform and early vision model is presented in this paper. The early vision model improves the antinoise and texture-sensitive capability of our algorithm and watershed transform provides a simple way to get one pixel wide and closed boundaries of ultrasound images. Furthermore, a local marker method is also put forward to solve the over-segmentation problem of watershed transform. The effectiveness of proposed scheme is demonstrated through experimental results on ultrasound images

关键词： Ultrasonic imaging Image segmentation Image edge detection Image processing Image texture analysis Humans Computer vision Merging Biomedical engineering Medical diagnosis

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Quadrature Doppler Ultrasound Signal Senoising Based on Adaptive Representations

Quadrature Doppler Ultrasound Signal Senoising Based on Adap...

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IEEE inst.umentation and Measurement technology Conference

作者： Xiaotao Wang Yi Shen Zhiyan Liu Qiang Wanf Department of Control Science and Engineering Harbin Institute of Technology Harbin China

The spectrogram of Doppler ultrasound signal has been widely used in the clinical diagnosis. The additional frequency component arising from noise will produce an adverse effect on the subjective analysis of the spectrogram and its quantitative analysis. Two approaches based on the adaptive representations including the adapted local cosine transform (CPD) and the wavelet packet (WPD), combined with the garrote thresholding, and is proposed to denoising quadrature Doppler ultrasound signal. At first, to avoid the phase distortion induced by denoising the complex Doppler ultrasound signal directly, the directional information is extracted from the quadrature signal. And then the denoising methods based on the adaptive representations are performed on the forward and reverse flow signals, respectively. At last, the estimated signal is reconstructed from the denoised signals using Hilbert transform. The simulation results have shown that these approaches are superior to ones based on the wavelet transform, especially under low SNR circumstances, and moreover, the denoising method using the CPD has achieved the best performance

关键词： Ultrasonic imaging Noise reduction Signal processing Frequency Discrete wavelet transforms Spectrogram Wavelet packets Blood flow Wavelet transforms Data mining

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Tracking a Maneuvering Target in Clutter by a New Smoothing Particle Filter

Tracking a Maneuvering Target in Clutter by a New Smoothing ...

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IEEE inst.umentation and Measurement technology Conference

作者： Yanqiu Li Yi Shen Zhiyan Liu Ping He Department of Control Science and Engineering Harbin Institute of Technology Harbin China

Tracking maneuvering target in cluttered environment is a problem of great theoretical and application interest. In this paper a new smoothing particle filter algorithm is proposed which combines the particle filter with a Gibbs sampler to perform the smoothing of the estimation of the target maneuvering and measurement origin. This algorithm is used to estimate states of a maneuvering target from its cluttered measurements, and the simulation results show its powerful ability to solve the problem

关键词： Target tracking Particle tracking Smoothing methods Particle filters Noise measurement State estimation Particle measurements Current measurement Time measurement Performance evaluation

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A Fast Medical Image Registration Method Based on Nonlinear Correlation Measurement

A Fast Medical Image Registration Method Based on Nonlinear ...

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IEEE inst.umentation and Measurement technology Conference

作者： Jing Jin Qiang Wang Yi Shen Department of Control Science and Engineering Harbin Institute of Technology Harbin China

In this paper a new approach to the problem of rigid body registration is proposed, using a concept of nonlinear correlation information entropy (NCIE) as the new matching criterion. The presented method applies NCIE to measure the correlation degree between the image intensities of corresponding voxel in both images. Registration is achieved by adjustment of the relative position until the NCIE between the images is maximized. However, unlike the mutual information, NCIE changes in the closed interval [0, 1], and around the extremum it varies sharply, which makes it possible that a threshold of NCIE can be used to boost the search to registration transformation. Using this feature of NCIE, we registered a rotated floating image with a reference image combined the variant step-size searching for further enhancing the searching speed. Our results demonstrate the proposed method can take care the differences in contrast between the floating and reference images. Meanwhile, as the mutual information, NCIE criterion can be achieved automatically and without any preprocessing

关键词： Biomedical imaging Image registration Optical imaging Medical diagnostic imaging Mutual information Information entropy Biomedical image processing X-ray imaging Anatomy Biomedical engineering

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Tracking a ballistic target with unscented iterative Kalman filter

Tracking a ballistic target with unscented iterative Kalman ...

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Annual Conference of Industrial Electronics Society

作者： Shu-Chun Zhang Si-Hua Liu Guang-Da Hu Department of Control Science and Engineering Harbin Institute of Technology Harbin China

Tracking a ballistic object in the reentry phase by processing radar measurements has attracted much attention of researchers, to make the estimations more accurate, the idea of iteration is often used in the process of updating which has no relationship with dynamics of the system. In this paper a new iterative method using unscented transform (UT) named UIKF is presented, the simulation results demonstrate its effectiveness.

关键词： Target tracking Nonlinear equations Filters Filtering Radar tracking State estimation Additive noise Noise measurement Time measurement control systems

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3D Elastic Registration of Ultrasound Images Based on Skeleton Feature

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Chinese Journal of Biomedical engineering(English Edition) 2005年第3期14卷 120-129页

作者： LI Dan-dan LIU Zhi-Yan SHEN Yi Department of Control Science and Engineering Harbin Institute of Technology P. O. Box 327 Harbin 150001 China

In order to eliminate displacement and elastic deformation between images of adjacent frames in course of 3D ultrasonic image reconstruction, elastic registration based on skeleton feature was adopt in this paper. A new automatically skeleton tracking extract algorithm is presented, which can extract connected skeleton to express figure feature. Feature points of connected skeleton are extracted automatically by accounting topical curvature extreme points several times. Initial registration is processed according to barycenter of skeleton. Whereafter, elastic registration based on radial basis function are processed according to feature points of skeleton. Result of example demonstrate that according to traditional rigid registration, elastic registration based on skeleton feature retain natural difference in shape for organr s different part, and eliminate slight elastic deformation between frames caused by image obtained process simultaneously. This algorithm has a high practical value for image registration in course of 3D ultrasound image reconstruction.

关键词： Elastic registration Morphology skeleton Ultrasound image

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