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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第4期10卷 497-503页

作者： Xin LIU Guo WEI Jin-wei SUN Dan LIU department of automatic Measurement and control Harbin Institute of Technology Harbin 150001 China

Least squares support vector machines (LS-SVMs) are modified support vector machines (SVMs) that involve equality constraints and work with a least squares cost function, which simplifies the optimization procedure. In this paper, a novel training algorithm based on total least squares (TLS) for an LS-SVM is presented and applied to multifunctional sensor signal reconstruction. For three different nonlinearities of a multifunctional sensor model, the reconstruction accuracies of input signals are 0.001 36%, 0.031 84% and 0.504 80%, respectively. The experimental results demonstrate the higher reliability and accuracy of the proposed method for multifunctional sensor signal reconstruction than the original LS-SVM training algorithm, and verify the feasibility and stability of the proposed method.

关键词： Least squares support vector machine Total least squares Multifunctional sensor Signal reconstruction

Measurement of spatial object's exterior attitude based on linear CCD

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Chinese Optics Letters 2008年第7期6卷 505-509页

作者：艾莉莉袁峰丁振良 department of automatic testing and control Harbin Institute of TechnologyHarbin 150001

It is difficult to realize real-time measurement of exterior attitude by the traditional systems based on the area image sensor which have conflict between speed and accuracy. The subsystem for three-dimensional （3D） coordinate reconstruction of point target （S3DCRPT） which is composed of three one-dimensional （1D） cameras based on linear charge-coupled device （CCD） can determine the distant light spots＇ spatial position. The attitude angle of the measured object is determined by the spatial solution while the coordinate reconstruction is separately carried on by the S3DCRPT with some point cooperation targets （PCTs） on the measured object. A new optical system is designed to solve the interference problem with one-to-one relationship between the PCTs and the S3DCRPT optical subsystems, which improves the measurement accuracy and saves space. The mathematical model of the attitude measurement is established, and partial and global calibrations are realized for the multi-camera attitude measurement system. The test results show the feasibility of the exterior attitude measurement based on linear CCD.

关键词： Cameras Charge coupled devices Computer networks Digital cameras Ketones Mathematical models Optical systems Real time systems Restoration Time measurement

A novel pose and illumination robust face recognition with a single training image per person algorithm

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Chinese Optics Letters 2008年第4期6卷 255-257页

作者：李君宝潘正祥 department of automatic test and control harbin institute of technology Harbin 150001 department of Electronic Engineering National Kaohsiung University of Applied Sciences Kaohsiung

In the real-world application of face recognition system, owing to the difficulties of collecting samples or storage space of systems, only one sample image per person is stored in the system, which is so-called one sample per person problem. Moreover, pose and illumination have impact on recognition performance. We propose a novel pose and illumination robust algorithm for face recognition with a single training image per person to solve the above limitations. Experimental results show that the proposed algorithm is an efficient and practical approach for face recognition.

关键词： Lighting

DCT based multipurpose watermarking technique for image copyright notification and protection

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Journal of harbin institute of technology(New Series) 2004年第3期11卷 237-239页

作者：姜守达陆哲明吴昊天 Dept. of automatic test and control Harbin Institute of Technology Harbin 150001 China

A multipurpose image watermarking technique based on DCT is proposed to notify and protect the copyright of digital products. In order to achieve this objective, the DCT coefficients of each image block are divided into two parts for embedding the visible and invisible watermarks. The visible watermark is embedded in each DC DCT coefficient and most of the AC DCT coefficients of every block, and the invisible watermark in the rest. Based on the characteristics of Human Visual System (HVS), the embedding strength of the visible watermark is varied in accordance with the underlying content of the host image. The invisible watermark is embedded in a quaternity of midrange frequencies. Experimental results show that the visible watermark is hard to remove and the invisible watermark is robust to common digital signal processing operations.

关键词： copyright notification visible watermark HVS quantization index modulation

Modeling of Electromagnetic Wave Propagation and Its Applicationin Virtual test

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Journal of harbin institute of technology(New Series) 2017年第2期24卷 1-9页

作者： Lianlei Lin Wensheng Su Shouda Jiang department of automatic test and control Harbin Institute of Technology Harbin 15001 China

With the development of virtual test,the computation of the effect of different weather conditions on electromagnetic wave propagation is required in many simulation systems. Firstly,this paper presents a unique point of view for computing the electromagnetic wave attenuation ratio under different weather conditions by means of an independent electromagnetic wave propagation component that can be directly implemented in virtual test, and is easy to configure and easy to reuse. We present an analysis of the principles of electromagnetic wave propagation and the algorithms designed for realization of various propagation models within the electromagnetic wave propagation component. Secondly,this paper presents a use-case analysis and outlines the design of the component,verifies the developed models under various weather conditions,and obtains equivalent values as those obtained theoretically. Finally,we build a virtual test system,verify the system in different weather conditions,and again obtain equivalent values to those obtained theoretically. The algorithms in the electromagnetic wave propagation component are developed in the C language, which substantially improves the computational speed,and meets the real-time requirements of the virtual testing platform.

关键词： electromagnetic wave propagation modeling and simulation virtual test

Feasibility Analysis of Accelerometer Configuration of Non-gyro Micro Inertial Measurement Unit

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Feasibility Analysis of Accelerometer Configuration of Non-g...

Stability Analysis of Distributed Parameter Systems on Temperature Measurement of Large-scale Objects

CES/IEEE 5th International Power Electronics and Motion control Conference

作者： DING Mingli ZHOU Qingdong WANG Qi and WANG Changhong department. of automatic test and control harbin institute of technology harbin China department. of control Science and Engineering harbin institute of technology harbin China department of automatic test and control Harbin Institute of Technology Harbin China department of control Science and Engineering Harbin Institute of Technology Harbin China

ISBN: (纸本)1424404487;9781424404483

＜正＞A sufficient condition is given to determine if a configuration of accelerometers of non-gyro micro inertial measurement unit （NGMIMU） is feasible. NGMIMU uses only accelerometers to compute the motion of a moving body. If the condition is satisfied, the angular acceleration and the linear acceleration in three directions can be expressed by the linear combination of the angular velocity and the accelerometer output. And the posture of a moving body can be estimated using a numerical iteration algorithm. Two configurations of accelerometers are analyzed in detail and the results verify the correctness of the condition. This research serves as an important criterion for the research of other problems of NGMIMU.

关键词： Measurement Unti Accelerometer Feasibility Configuration

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Journal of Thermal Science 2007年第3期16卷 248-253页

作者： Zhenliang DING Li ZHONG Feng YUAN department of Electronic Engineering School of Automatic Measurement and Control Harbin Institute of Technology 150001 Harbin China

In this paper, the mechanical construction, thermal regulator design and temperature measurement system of a local area were set up for large-scale linear measurement. Numerical analysis based on temperature correlated characteristic is discussed to obtain optimal observation points for the measurements. The horizontal temperature distribution of the measured area is compared with the measurement of the variation of temperature at 15℃ and 20℃ over time, and characteristic of dynamic response is also discussed. In addition, the long-time stability of measured temperature is analyzed by means of using the standard deviation. It characterizes the temperature distribution performance of a large area and how it may impact the measurement of a large-scale object.

关键词： temperature control temperature measurement distribution parameter linear measurement.

RESEARCH ON THE MINIMUM ZONE CYLINDRICITY EVALUATION BASED ON GENETIC ALGORITHMS

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Chinese Journal of Mechanical Engineering 2003年第2期16卷 167-170页

作者： Cui ChangcaiChe RenshengYe DongHuang Qingchengdepartment of automatic Measurement and control,harbin institute of technology, harbin 150001, China department of automatic Measurement and control Harbin Institute of Technology Harbin 150001 China

A genetic algorithm (GA)-based method is proposed to solve the nonlinearoptimization problem of minimum zone cylindricity evaluation. First, the background of the problemis introduced. Then the mathematical model and the fitness function are derived from themathematical definition of dimensioning and tolerancing principles. Thirdly with the least squaressolution as the initial values, the whole implementation process of the algorithm is realized inwhich some key techniques, for example, variables representing, population initializing and suchbasic operations as selection, crossover and mutation, are discussed in detail. Finally, examplesare quoted to verify the proposed algorithm. The computation results indicate that the GA-basedoptimization method performs well on cylindricity evaluation. The outstanding advantages concludehigh accuracy, high efficiency and capabilities of solving complicated nonlinear and large spaceproblems.

关键词： genetic algorithm (GA) cylindricity form error minimum zone

Algorithmic Study of M-Estimators for Multi-Function Sensor Data Reconstruction

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Tsinghua Science and technology 2007年第1期12卷 9-13页

作者：刘丹孙金玮魏国 department of automatic Measurement and control Harbin Institute of Technology

This paper describes a data reconstruction technique for a multi-function sensor based on the Mestimator, which uses least squares and weighted least squares method. The algorithm has better robustness than conventional least squares which can amplify the errors of inaccurate data. The M-estimator places particular emphasis on reducing the effects of large data errors, which are further overcome by an iterative regression process which gives small weights to large off-group data errors and large weights to small data errors. Simulation results are consistent with the hypothesis with 81 groups of regression data having an average accuracy of 3.5%, which demonstrates that the M-estimator provides more accurate and reliable data reconstruction.

关键词： least squares weighted least squares M-estimators data reconstruction

Application of MSPCA to Sensor Fault Diagnosis

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自动化学报 2006年第3期32卷 417-421页

作者： XU Tao WANG Qi department of automatic test and control Harbin Institute of Technology Harbin 150001

A multiscale principal component analysis method is proposed for sensor fault detection and identification. After decomposition of sensor signal by wavelet transform, the coarse-scale coefficients from the sensors with strong correlation are employed to establish the principal component analysis model. A moving window is designed to monitor data from each sensor using the model. For the purpose of sensor fault detection and identification, the data in the window is decomposed with wavelet transform to acquire the coarse-scale coefficients firstly, and the square prediction error is used to detect the failure. Then the sensor validity index is introduced to identify faulty sensor, which provides a quantitative identifying index rather than qualitative contrast given by the approach with contribution. Finally, the applicability and effectiveness of the proposed method is illustrated by sensors of industrial boiler.

关键词：小波传输传感器故障诊断 MSPCA