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Uncertainty of thin cylinder diameter measured by means of optical diffraction

Guangdian Gongcheng/Opto-Electronic engineering 2005年第7期32卷 55-58页

作者： Cui, Jian-Wen Zhang, Jun Tang, Wen-Yan Li, Hui-Peng Department of Automation Measurement and Control Engineering Harbin Institute of Technology Harbin 150001 China

To improve measurement accuracy of thin cylinder's diameter by optical diffraction, an improved model is established with recursive method, which is more accurate. Theoretical error of customary model created by diffraction angle is eliminated so that the measurement accuracy is improved when the diameter is measured with the improved model. The uncertainty of measurement is created by three cases, namely the wavelength error of light source, position error of dark fringe and adjustment error of focal length of lens. The uncertainty errors due to above three cases are 0.024 μm, 1.920 μm and 0.529 μm respectively calculated with the improved model. Experimental results show that the relative measurement error is less than 0.5%, which is better than the present level of 1%, and uncertainty of measurement is less than 2 μm, which agrees well with theoretical analysis.

关键词： Cylindrical measurement Diameter measurement Fraunhofer diffraction Measuring errors

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Contour extraction of a moving vehicle in visible images based on image fusion

Contour extraction of a moving vehicle in visible images bas...

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International Conference on Machine Learning and Cybernetics, ICMLC 2005

作者： Zhao, Peng Wang, Ni-Hong Pu, Zhao-Bang Information and Computer Engineering Institute North East Forestry University Harbin City 150040 China Department of Automation Measurement and Control Harbin Institute of Technology Harbin City 150001 China

ISBN: (纸本)078039092X

Infrared (IR) and visible images are commonly used in the detection and tracking of a moving target. A novel contour extraction scheme for a moving vehicle is proposed in this paper. Firstly, a motion segmentation technology is applied to get an initial contour. Secondly, a dynamic contour is applied to represent the initial contour and then converges to the target's contour. Lastly, a novel image fusion is proposed, which minimizes the B-spline norm's square of control point vector's difference in two modal images. Image registration is not required. The experiment indicates that for visible images, average contour extraction error decreases by 58.14% after the fusion. Moreover, a fast iteration algorithm of dynamic contour based on the Newmark algorithm is devised. This image fusion is implemented only with control point vectors and is suitable for real-time processing. © 2005 IEEE.

关键词： Feature extraction

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Linear quadratic regulation for linear time-varying systems with multiple input delays part I: Discrete-time case

Linear quadratic regulation for linear time-varying systems ...

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5th International Conference on control and Automation, ICCA'05

作者： Zhang, Huanshui Duan, Guangren Xie, Lihua Harbin Institute of Technology HIT Campus Shenzhen University Town Xili Shenzhen 518055 China Center for Control Theory and Guidance Technology Harbin Institute of Technology Harbin 150001 China BLK S2 School of Electrical and Electronic Engineering Nanyang Technological University Singapore 639798 Singapore

ISBN: (纸本)0780391381

Although the problem of linear quadratic regulation has been well studied for discrete linear systems without delays or with only a single input delay in the past decades, the same problem for systems with multiple input delays remains to be solved. This paper aims to present a complete solution to the LQR problem for systems with multiple input delays. It shall be shown that the problem is dual to that of fixed-lag smoothing for a backward system without involving delays. Thus, the optimal LQR controller can be obtained by computing the gain matrices of the standard fixed-lag smoothing. An explicit solution for the LQR problem is given in terms of the solution of a Riccati difference equation. © 2005 IEEE.

关键词： Linear systems

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Robust control design for stiffness measurement of flexible joint

Robust control design for stiffness measurement of flexible ...

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International Conference on Machine Learning and Cybernetics (ICMLC)

作者： Guang-Lin Wang Yun-Feng Li Yun-Li Wu Department of Mechanical Engineering and Automation Harbin Institute of Technology Harbin China Center for Control Theory and Guidance Technology Harbin Institute of Technology Harbin China

Flexible joint, one kind of force-sensing element, is a key part of flexible gyro. Its stiffness is very small such that it is easily disturbed by noises in working environment. During the development of the instrument of its stiffness measuring, instability is the main factor affecting the measuring precision. This paper firstly presents a model for stiffness measuring system subjected to disturbance. Based on the model, robust H/sub /spl infin// control design for stiffness measurement of flexible joint is proposed by using a complete parametric approach of eigenstructure assignment to stabilize the stiffness measuring system and guarantee the specified H/sub /spl infin//-norm upper-bound constraint. Finally, the results of simulation show the effect of the proposed approach.

关键词： Robust control control design Neck Instruments Riccati equations Force sensors Mechanical engineering Automation control theory Working environment noise

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An experimental comparison on Gabor wavelet and wavelet frame based features for image retrieval

An experimental comparison on Gabor wavelet and wavelet fram...

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9th International Conference on Knowledge-Based Intelligent Information and engineering Systems, KES 2005

作者： Qiao, Yu-Long Pan, Jeng-Shyang Sun, Sheng-He Department of Automatic Test and Control Harbin Institute of Technology P.O. Box 339 Harbin Heilongjiang China Department of Electronic Engineering National Kaohsiung University of Applied Sciences Taiwan Taiwan

ISBN: (纸本)3540288961

The mean and standard deviation of the magnitudes of coefficients of the transform domain are common used in texture image retrieval. This paper performs an experimental comparison on Gabor wavelet and wavelet frame based features for this application. The detail comparison results indicate the performance of the former is not superior over that of the last in the query-by-example retrieval. © Springer-Verlag Berlin Heidelberg 2005.

关键词： Image retrieval

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Analysis of One and Two Dimensional Fuzzy controllers

Analysis of One and Two Dimensional Fuzzy Controllers

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IEEE International Conference on Fuzzy Systems (FUZZ-IEEE)

作者： Xiaojun Ban X.Z. Gao Xianlin Huang T.B. Wu Department of Control Theory and Engineering Harbin Institute of Technology Harbin China Institute of Intelligent Power Electronics Helsinki University of Technology Espoo Finland

In our paper, the analytical structures and properties of the one and 2D fuzzy controllers are first investigated in details. The nature of these two kinds of fuzzy controllers is next probed from the viewpoint of control engineering. For the one dimensional fuzzy controller, it is concluded that this controller is a combination of a saturation element and a nonlinear proportional controller, and the system that employs the one dimensional fuzzy controller is the combination of an open-loop control system and a closed-loop control system. On the other hand, the 2D controller is a hybrid controller, which comprises the saturation part, zero-output part, nonlinear derivative part, nonlinear proportional part, as well as nonlinear proportional-derivative part, and the 2D fuzzy controller-based control system is a loop-varying system with varying number of control loops

关键词： Fuzzy control Proportional control Nonlinear control systems control systems Open loop systems Pi control PD control Three-term control control theory Paper technology

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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 Instrumentation 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 Instrumentation 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 Instrumentation 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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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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