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6th International Forum on Strategic technology, IFOST 2011

作者： Yun, Huijuan Sun, Zhenkun Yang, Ling Han, Limei Liu, Wei Higher Educ. Key Lab. for Measuring and Contr. Technol. and Instrum. of Heilongjiang Province College of Measure-Control Tech. and Communication Engineer Harbin University of Science and Technology Harbin 150080 China

ISBN: (纸本)9781457703966

In modern industry, the geometric accuracy of gears is demanded increasingly high. Requirement of the accuracy of gear measuring instruments is also higher and higher. When the mechanical system has been formed, the accuracy of gear measuring center mainly depends on the control system. Based on Turbo PMAC2 motion controller, in this paper, we design a control system of gear measuring center, and develop the underlying database software of the controller and host computer communication link library software. After testing this system, we get the results which show that the measurement accuracy and repeatability of the instrument are improved. © 2011 IEEE.

关键词： controllers

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The APFC system based on an improved duty cycle control algorithm

The APFC system based on an improved duty cycle control algo...

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6th International Forum on Strategic technology, IFOST 2011

作者： Wu, Li-Hua Gao, Hui-Zhi Ma, Huai-Jian Liang, Hong Higher Educ. Key Lab. for Measuring and Contr. Technol. and Instrum. of Heilongjiang Province College of Measure-Control Tech. and Communication Engineer Harbin University of Science and Technology Harbin 150080 China

ISBN: (纸本)9781457703966

Aiming at the problem that the digital control Power Factor Correction technology has some deficiencies in the dynamic responses and stability, a new Active Power Factor Correction(APFC) system based on an improved duty cycle control algorithm is designed in this paper. In this algorithm, when the load and the input voltage go step change, the output voltage ripple and the input voltage feed-forward are introduced to compensate the duty cycle during each switch cycle to ensure the input current an undistorted sinusoid. So it guarantees the high speed of dynamic response and the stability of the APFC system. Also the efficiency and reliability of the APFC system are improved by applying minimal voltage active-clamp soft-switching technology, which can inhibit the reverse recovery of diodes effectively. © 2011 IEEE.

关键词： Dynamic response

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An improved algorithm to reduce nonlinear distortion by clipping reconstructing iteration method

An improved algorithm to reduce nonlinear distortion by clip...

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2011 Cross Strait Quad-Regional Radio Science and Wireless technology Conference, CSQRWC 2011

作者： Liu, Mingzhu Xu, Lanzhi Yu, Qi Higher Educ. Key Lab. for Measuring and Contr. Technol. and Instrumentations of Heilongjiang Prov. College of Measure-Control Tech. and Communication Engineer Harbin University of Science and Technology Harbin China Technology Department Heilongjiang Broadcasting Station Harbin China

ISBN: (纸本)9781424497904

One of the efficient ways to reduce the peak-to-average power ratio in multi-carrier system is clipping, but it may cause the outspread of frequency spectrum, and lead to clipping noise as well as nonlinear distortion, and at the same time it can increase the bit error ratio in multi-carrier system. In this paper, a nonlinear and non-inertial system model has been constructed, which is described the statistic characteristics of clipping process, and has become the fundamental framework in the following analysis. In the model, the statistic characteristics of clipping noise and distortion are looked as Gaussian distribution. On the other hand, an improved algorithm for reducing the clipping noise and distortion has been given in this paper. The proposed algorithm used discrimination and iteration procedure to reconstruct clipping noise and distortion, and then minished their adverse effect by counteractive operation. Simulation results showed that clipping reconstructing iterative algorithm could not obviously increase peak-to-average power ratio of clipping system, but it could effectively reduce the influence of nonlinear distortion and improve the BER performance under various amplitude thresholds and different iteration times. © 2011 IEEE.

关键词： Peak to average power ratio

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Preprocessing of palm image based on wavelet modulus maximum value

Preprocessing of palm image based on wavelet modulus maximum...

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IEEE 2011 10th International Conference on Electronic Measurement and Instruments, ICEMI 2011

作者： Dong, Jingwei Sun, Yan Huang, Yaping Hu, Silue School of Measure-control Technology and Communication Engineering Harbin University of Science and Technology Harbin 150040 China Higher Educ. Key Lab. for Measuring and Contr. Technol. and Instrumentations of Heilongjiang Prov. Harbin 150040 China Engineering Department Harbin University Harbin 150080 China

ISBN: (纸本)9781424481590

Authentication technology based on geometric characteristics of hand image has the advantages of high speed and easy operation. So handkey becomes another biological characteristics authentication system as fingerprint key. Palm image preprocessing is the basic of hand shape recognition system. Denoising is a necessary preprocessing before edge detection of palm image. The paper introduces a denoising method, wavelet modulus maximum value method. The wavelet transforming has the advantage of multi-resolution either in time domain or in frequency domain, so it can be used to describe the partial characteristics in the both domain. Wavelet denoising is a more successful kind of application of wavelet transforming. Because of the multi-resolution of wavelet, the non-steady characteristics of signals can be described better. The principle and processing steps of the algorithm are described in this paper in details. Experiments show that the method not only can remove noise effectively, but also keeps edge details of the hand image. The preprocessing program designed in MATlab.is listed in the paper, the original hand image and edge detect image after wavelet denoising are shown, too. © 2011 IEEE.

关键词： MATlab

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Balance control of two-wheeled self-balancing mobile robot based on TS fuzzy model

Balance control of two-wheeled self-balancing mobile robot b...

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6th International Forum on Strategic technology, IFOST 2011

作者： Qin, Yong Liu, Yanlong Zang, Xizhe Liu, Ji College of Measurement and Control Technology and Communication Engineering Higher Educ. Key Lab. for Measuring and Contr. Technol. and Instrum. of Heilongjiang Province Harbin University of Science and Technology Harbin 150080 China Robotics Institute Harbin Institute of Technology Harbin 150080 China School of Mechanical and Automotive Engineering South China University of Technology Guangzhou 150080 China

ISBN: (纸本)9781457703966

Two-wheeled self-balancing robot is a mechanically unstable, nonholonomic constraint robot. This paper has established a dynamics and kinematics for nonholonomic mobile robot. In order to control more effective for self-balancing robot's balance model, has designed fuzzy controller based on the T-S fuzzy model with the parallel distribution compensator (PDC) the structure. It realizes the robot balance and the movement control. Finally, validity and feasibility of the system modeling and the designed controller were confirmed through the actual test results and the simulation results contrast analysis. © 2011 IEEE.

关键词： Mobile robots

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Uncertainty evaluation of coded structured light system for highaccuracy shape reconstruction of porcelain

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Journal of Convergence Information technology 2011年第10期6卷 115-121页

作者： Wu, Haibin Wang, Liquan Cui, Jingyan Yu, Xiaoyang College of Mechanical and Electrical Engineering Harbin Engineering University Harbin China Higher edu. key lab. for Measuring and Control Tech. and Instrumentations of Heilongjiang province Harbin University of Science and Technology Harbin China Harbin Third Power Plant of Huadian Energy Harbin China

The configuration and measuring method of a coded structured light system can be optimized by evaluating the uncertainty. In order to reconstruct high reflectance surface of porcelain, simplified mathematic model and encoding/decoding method by edge Gray code of structured light system are proposed. The former has visualized and easy-calibration system parameters. The later reduces theoretical quantization error and decoding error against traditional Gray code, so measurement accuracy is improved. Experimental results show that error of measured high reflectance unicolor standard plane is 0.6~0.8mm, and reconstructed porcelain shape has same visual effect as the real one. Type B Evaluation based on uncertainty evaluation of error sources in mathematic model and transfer coefficients has similar result as Type A Evaluation based on measured data on standard plane. According to the analysis, accuracy of sub-pixel edge location has the largest influence to uncertainty, and accuracy of calibrated azimuth parameters is important to uncertainty.

关键词： Reflection

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Design of sensor model based on casein detection

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Guangxue Jingmi Gongcheng/Optics and Precision Engineering 2011年第7 SUPPL.期19卷 382-389页

作者： Qin, Yong Zhou, Zhen Hou, Jing Wang, Li-Jie The Higher Educ. Key Lab. on Measuring and Control Technology and Instrum. of Heilongjiang Province College of Measure-Control Technology and Communication Engineering Harbin University of Science and Technology Harbin 150080 China

In order to perform a quantitative analysis of a casein element, we simulate the scattering characteristics of casein, analyze the effect of the shape of a sample cell and the light source wavelength in the detection equipment on the casein detection and establish a sensor model for casein detection. All of these aspects are based on researching the scattering characteristics of a casein micelle. Using Mie scattering, we establish the scattering models of casein, including a cylinder cross-section and a square sample cell. Through irradiating different sample cells, we have analyzed the light intensity at all angles, and the light sensitivity for different wavelengths. The simulation result indicates that a square sample cell at 0° and 90° is more amenable to the detection the light intensity, which technically can meet correlative requirements. According to the simulation results, we demonstrate the detection sample cell of the casein element by using wavelengths of 1333 nm and 1600 nm as the laser source.

关键词： Light scattering

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Alignment DNA sequence applied in stereo vision

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Guangxue Jingmi Gongcheng/Optics and Precision Engineering 2011年第7 SUPPL.期19卷 248-254页

作者： Yu, Shu-Chun Yu, Xiao-Yang Fan, Jian-Ying Sun, Yu The Higher Educ. Key Lab. for Measuring and Control Tech. and Instrum. of Heilongjiang Province Harbin University of Science and Technology Harbin 150080 China

In order to increase practicability of stereo vision with high matching accuracy and short matching time, an stereo matching method based on an alignment DNA sequence was presented. The similarity of alignment DNA sequence and stereo matching was deeply analyzed, and then the theoretical frame of stereo matching based on the alignment DNA sequence was found. This method divided into 4 stages: every epipolar in stereo image was transformed into a DNA sequence;score matrix was built with the homonymous epipolar;optimal path was searched on score matrix and the disparity is computed;stripes error is corrected by Ground control Points(GCPs). Experimental results show that the time of processing Tuskuba stereo pairs is only 0.504 s by using the proposed method, which is respectively 1/6 of graph-cut, 1/4 of belief-propagation and 1/2 of dynamic programming. It is indicated that the method has a fast processing and good matching precision.

关键词： DNA sequences

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Classification method of SPIHT coding image resynchronization transmission

Classification method of SPIHT coding image resynchronizatio...

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2010 2nd IITA Conference on Geoscience and Remote Sensing, IITA-GRS 2010

作者： Shen, Wang Ye, Zhang Yudong, Guan Aili, Wang School of Electronics and Information Engineering Harbin Institute of Technology Harbin 150001 China Higher Educational Key Lab. for Measuring and Control Technology and Instrumentations of Heilongjiang Harbin University of Science and Technology Harbin 150040 China

ISBN: (纸本)9781424485154

A source and channel coding scheme for image transmission over noisy channel is presented in this paper. There is crude block structure in the wavelet coefficient of images. Coding each image blocks independently and reassigning its bitstream can achieve the resynchronization of decoding image in receiving terminal to improve the image's ability to resist noisy. But different image block has different character, and has different energy distribution, so it's hard to implement consistency in rate-distortion performance. Paper proposes a classification method based on high frequency subband energy distribution of wavelet. Give different codeword length to different type image block to achieve better rate distortion performance. Experimental results show that the proposed scheme is able to provide better image quality than scheme without using the classification method in range of some BER. © 2010 IEEE.

关键词： Image coding

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Design of coded structured light system for high reflectance surface

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Guangxue Jingmi Gongcheng/Optics and Precision Engineering 2011年第7 SUPPL.期19卷 18-24页

作者： Wu, Hai-Bin Wang, Li-Quan Cui, Jing-Yan Yu, Xiao-Yang College of Mechanical and Electrical Engineering Harbin Engineering University Harbin 150001 China The Higher Educ. Key Lab. on Measuring and Control Technology and Instrum. of Heilongjiang Province Harbin University of Science and Technology Harbin 150080 China Harbin Third Power Plant of Huadian Energy Harbin 150024 China

In order to explore the measuring accuracy of a coded-structured-light 3D measurement system onto a high reflectance color surface, the measuring error analysis, system parameter design and encoding/decoding principle were investigated. First, the analytic geometry model and projective geometry model of the coded structured light system were analyzed and their device parameters and azimuth parameters were unified. Second, based on the analytic geometry model, the quantization relationship between measuring errors and location errors of image sampling points, distances and including the angle from a projector to a camera, the view angle of the projector and the camera were analyzed. Finally, system parameters were designed by considering the system range, shelter, depth of field, luminous power and the system capacity and edge gray code was adopted. Experimental results indicate that the error of measured high reflectance unicolor standard plane is 0.6~0.8 mm, and the reconstructed porcelain shape has the same visual effect as the real one. It can basically meet the requirements of measurement and reconstruction for the high reflectance color surface in civil fields.

关键词： Reflection

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