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Identification of Eye Movements from Non-frontal Face Images for Eye-controlled Systems

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International Journal of Automation and computing 2014年第5期11卷 543-554页

作者： Min Lin Bin Li Qiao-Hong Liu School of Mechatronic Engineering and Automation Shanghai University Shanghai medical instrumentation college University of Shanghai Science and Technology

The novel eye-based human-computer interaction(HCI) system aims to provide people, especially, disabled persons,a new way of communication with surroundings. It adopts a series of continual eye movements as input to perform simple control activities. Identification of eye movements is the crucial technology in these eye-based HCI systems. At present, researches on eye movement identification mainly focus on frontal face images. In fact, acquisition of non-frontal face images is more reasonable in real applications. In this paper, we discuss the identification process of eye movements from non-frontal face images. Firstly, the original head-shoulder images of 0?–±60?azimuths are sampled without any auxiliary light source. Secondly, the non-frontal face region is detected by using the Adaboost cascade classifiers. After that, we roughly extract eye windows by the integral projection ***, we propose a new method to calculate the x- y coordinates of the pupil center point by searching the minimal intensity value in the eye windows. According to the trajectory of the pupil center points, different eye movements(eye moving left, right, up or down)are successfully identified. A set of experiments is presented.

关键词： Eye movement identification non-frontal face images pupil center localization human-computer interaction eye-based system

Output performance optimization for RTD fluxgate sensor based on dynamic permeability

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Science China(Information Sciences) 2016年第11期59卷 182-194页

作者： Yanzhang WANG Shujun WU Hao LU Defu CHENG Chen CHEN Na PANG Yunxia WAN Zhijian ZHOU Siyu CHEN college of instrumentation and Electrical Engineering Jilin University Key Laboratory of Geo-Exploration instrumentation Ministry of Education Jilin University

The output performance of residence times difference(RTD) fluxgate may vary under different driving conditions(driving currents and frequencies) and core materials. To optimize the RTD fluxgate and simplify its design process, an analytical model is employed to select the parameters and identify the effective factors that dominate the performance. The dynamic permeability parameters(Pi), which reflect the changes in the magnetization curve, are mathematically analyzed in detail. The linear variation functions of Pi in different driving conditions are fitted by using the dynamic arctangent hysteresis model. Consequently, the selection of driving conditions and core materials, which are assessed by comparing the experiment and simulation results,has an important role in achieving the optimal output performance of the RTD fluxgate.

关键词： RTD fluxgate hysteresis loop analysis of dynamic permeability simulation output response

Velocity calibration for microseismic event location using surface data

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Petroleum Science 2016年第2期13卷 225-236页

作者： Hai-Yu Jiang Zu-Bin Chen Xiao-Xian Zeng Hao Lv Xin Liu Key Laboratory of Geo-Exploration and instrumentation of Ministry of Education College of Instrumentation and Electrical EngineeringJilin University

Because surface-based monitoring of hydraulic fracturing is not restricted by borehole geometry or the difficulties in maintaining subsurface equipment, it is becoming an increasingly common part of microseismic monitoring. The ability to determine an accurate velocity model for the monitored area directly affects the accuracy of microseismic event locations. However, velocity model calibration for location with surface instruments is difficult for several reasons： well log measurements are often inaccurate or incomplete, yielding intractable models; ori- gin times of perforation shots are not always accurate; and the non-uniqueness of velocity models obtained by inver- sion becomes especially problematic when only perforation shots are used. In this paper, we propose a new approach to overcome these limitations. We establish an initial velocity model from well logging data, and then use the root mean square （RMS） error of double-difference arrival times as a proxy measure for the misfit between the well log velocity model and the true velocity structure of the medium. Double-difference RMS errors are reduced by using a very fast simulated annealing for model perturbance, and a sample set of double-difference RMS errors is then selec- ted to determine an empirical threshold. This threshold value is set near the minimum RMS of the selected samples, and an appropriate number of travel times within the threshold range are chosen. The corresponding velocity models are then used to relocate the perforation-shot. We use the velocity model with the smallest relative location errors as the basis for microseismic location. Numerical analysis with exact input velocity models shows that although large differences exist between the calculated and true velocity models, perforation shots can still be located to their actual positions with the proposed technique; the location inaccuracy of the perforation is 〈2 m. Further tests on field data demonstrate the validity of this techni

关键词： Velocity calibration Microseismicmonitoring Double-difference RMS error Very fastsimulated annealing Perforation-shot relocation

Analysis of sEMG signal for KOA classification

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Journal of Harbin Institute of Technology(New Series) 2011年第6期18卷 113-119页

作者：李玉榕廖志伟杜民 college of Electrical Engineering and Automation Fuzhou University Fujian Key Laboratory of medical instrumentation & Pharmaceutical Technology

The sEMG signals are collected from the vastus lateralis,vastus medialis,biceps femoris,and semitendinosus of lower extremity during level walking among control subjects and knee osteoarthritis (OA) patients,the latter including mild,moderate and severe *** 5-fold cross-validation is used to measure the accuracy of the proposed analysis algorithm on collected sEMG *** comparison,the more classical feature vectors of form factor,degree of skewness,kurtosis,and wavelet entropy are also *** experiment,the normalized energy ratio and marginal spectrum ratio achieve larger accuracy than the other features for all the four muscular *** the accuracy of vastus medialis and biceps femoris are larger than that of vastus lateralis and *** results suggest that the normalized energy ratio and marginal spectrum ratio via the analysis of knee sEMG signals by HHT can server as characteristic parameters to easily classify osteoarthritis with noninvasive *** more important muscular groups for maintaining the knee joint function are medialis and biceps femoris;as a result of that they should be exercise especially for rehabilitation.

关键词： osteoarthritis (OA) noninvasive diagnosis surface electromyography (sEMG) Hilbert-Huang Transform (HHT) neural network classifier

Excellent ethanol sensing properties based on Er_2O_3-Fe_2O_3 nanotubes

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Chinese Physics B 2015年第11期24卷 604-609页

作者：刘唱白何滢王圣蕾 college of Electronic Science & Engineering Jilin University college of instrumentation & Electrical Engineering Jilin University

In this work, pure α-Fe2O3 and Er2O3-Fe2O3 nanotubes were synthesized by a simple single-capillary electrospin- ning technology followed by calcination treatment. The morphologies and crystal structures of the as-prepared samples were characterized by scanning electron microscopy and x-ray diffraction, respectively. The gas-sensing properties of the as-prepared samples have been researched, and the result shows that the Er2O3-Fe2O3 nanotubes exhibit much better sen- sitivity to ethanol. The response value of Er2O3-Fe2O3 nanotubes to 10 ppm ethanol is 21 at the operating temperature 240α, which is 14 times larger than that of pure α-Fe2O3 nanotubes （response value is 1.5）. The ethanol sensing properties of α-Fe2O3 nanotubes are remarkably enhanced by doping Er, and the lowest detection limit of Er2O3-Fe2O3 nanotubes is 300 ppb, to which the response value is about 2. The response and recovery times are about 4 s and 70 s to 10 ppm ethanol, respectively. In addition, the Er2O3-Fe2O3 nanotubes possess good selectivity and long-term stability.

关键词： Er203 -Fe203 nanotubes ethanol gas sensing

Ion behavior and interelectrode breakdown voltage of a drift tube

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Chinese Physics C 2015年第5期39卷 98-104页

作者：耿浩赵忠俊段忆翔 Research Center of Analytical instrumentation Analytical & Testing Center Sichuan University Research Center of Analytical instrumentation College of Chemistry Sichuan University Research Center of Analytical instrumentation College of Life Science Sichuan University

We experimentally studied ion behavior and interelectrode breakdown voltage. The ion behavior of a drift tube directly influences the detection of ion intensity, and then influences the detection sensitivity of a system. Interelectrode voltage and pressure directly influence the ion behavior. Gas discharge between electrodes influences the adjustments required for interelectrode voltage. The experimental results show： ion intensity increases exponentially with the increment of voltage between drift electrodes; ion intensity decreases exponentially as pressure increases; with the increment of pressure, the breakdown voltage at first decreases, and then increases; ion injection has a significant influence on breakdown voltage, and this influence depends on the pressure and shapes of the electrodes. We explain the results above through assumptions and by mathematical methods.

关键词： drift tube breakdown voltage ion behavior

A Hydrogel's Formation Device for Quick Analysis of Liquid Samples Using Laser-Induced Breakdown Spectroscopy

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Plasma Science and Technology 2016年第6期18卷 661-665页

作者：郭广盟王杰边访田地樊庆文 college of instrumentation & Electrical Engineering Jilin University School of Manufacturing Science and Engineering Sichuan University Research Center of Analytical instrumentation College of Life ScienceSichuan University

The laser-induced breakdown spectroscopy technique has irreplaceable advantages in the field of detection due to its multi-phase specimen detection *** development of the LIBS technique for liquid analysis is obstructed by its inherent drawbacks like the surface ripples and extinction of emitted intensity,which make it *** this work,an in-situ hydrogel formation sampling device was designed and used the hydrogel as the detection phase of LIBS for Cu,Cr and Al in an aqueous *** the measured amount of resin placed in the device,the formed hydrogel could be obtained within 20 s after putting the device into water *** formed hydrogel could be directly analyzed by LIBS and reflect the elemental information of the water *** prominent performance made this hydrogel＇s formation device especially suitable for quick in-situ environmental liquid analysis using LIBS.

关键词： laser-induced breakdown spectroscopy quick analysis liquid samples hydrogel formation

Improved Full Bridge Converter with Low Peak Voltage on Rectifier Diodes

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Journal of Donghua University(English Edition) 2015年第1期32卷 62-67页

作者：薛开昶范鹏林君周逢道刘长胜 college of instrumentation and Electrical Engineering Jilin University

To suppress peak voltage on rectifier diodes in a full bridge( FB) converter,the mechanism of peak voltage was analyzed and an improved FB converter was proposed. One reason for peak voltage is the resonance of the transformer's leakage inductance and the rectifier diodes' junction capacitances. The other reason is that the fast reverse recovery current of the rectifier diodes flows through the transformer's leakage inductance. An H bridge composed of four diodes,an auxiliary inductance, and a clamping winding were adopted in the proposed converter,and peak voltage was suppressed by varying the equivalent inductance, principally in different operating modes. Experimental results demonstrate that the peak voltage of rectifier diodes decreases by 43%,the auxiliary circuit does not lead to additional loss, and the rising rate, resonant frequency,and amplitude of the rectifier diodes' voltage *** voltage and electromagnetic interference( EMI) of rectifier diodes are suppressed.

关键词： full bridge(FB) converter rectifier diodes peak voltage efficiency electromagnetic interference(EMI)

Traditional Chinese Medicine Diagnosis and Evaluation of the Clinical Effect in Post-hepatitic Cirrhosis based on Fuzzy Analysis

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Journal of Shanghai Jiaotong university(Science) 2008年第4期13卷 426-429页

作者：章浩伟朱训生 medical instrumentation college University of Shanghai for Science & Technology School of Mechanical Engineering Shanghai Jiaotong University

In view of the problem of traditional Chinese medicine (TCM) diagnosis, fuzzy comprehensive evaluation is introduced to the diagnosis and evaluation of the clinical effect of hepatitis. A new diagnosis and evaluation model of the TCM clinical effect standard was presented. The old disputed evaluation model by subjective analysis can be displaced by this objective method in its evaluation system. The foundation of this method is the fuzzy diagnosis model. This method has been realized to diagnose hepatitis and its values in practice has been validated through examples of clinical syndromes of post-hepatitic cirrhosis.

关键词： fuzzy comprehensive evaluation curative effect evaluation post-hepatitic cirrhosis