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Wavelet-based multispectral face recognition 被引量:6
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作者 LIU Dian-ting ZHOU Xiao-dan WANG Cheng-wen 《Optoelectronics Letters》 EI 2008年第5期384-386,共3页
This paper proposes a novel wavelet-based face recognition method using thermal infrared (IR) and visible-light face images. The method applies the combination of Gabor and the Fisherfaces method to the reconstructed ... This paper proposes a novel wavelet-based face recognition method using thermal infrared (IR) and visible-light face images. The method applies the combination of Gabor and the Fisherfaces method to the reconstructed IR and visible images derived from wavelet frequency subbands. Our objective is to search for the subbands that are insensitive to the variation in expression and in illumination. The classification performance is improved by combining the multispectal information coming from the subbands that attain individually low equal error rate. Experimental results on Notre Dame face database show that the proposed wavelet-based algorithm outperforms previous multispectral images fusion method as well as monospectral method. 展开更多
关键词 子波装置 识别方法 红外线 可见光
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Location algorithm for seal imprints on Chinese bank-checks based on region growing 被引量:5
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作者 CHEN Li-jiang LIU Tie-gen +3 位作者 CHEN Jia-Jia ZHU Jun-chao DENG Ji-Jie MA She-xiang 《Optoelectronics Letters》 EI 2006年第2期155-157,共3页
The paper focuses on location of seal imprints on Chinese bank-checks based on region growing.Region growing method can be applied to searching and locating connection region in an image.A seal imprint,however,is gene... The paper focuses on location of seal imprints on Chinese bank-checks based on region growing.Region growing method can be applied to searching and locating connection region in an image.A seal imprint,however,is generally composed of various connection regions which are unconnected to each other.In order to locate the seal imprint,these connection regions must be fused together.In the paper,an algorithm for locating seal imprints on Chinese bankchecks based on region growing is proposed, of which a fusion criterion for connection regions in a seal imprint is put forth based on the image feature of Chinese bankcheck,and a center-rays model is proposed to find the topological relationship between connection regions,for which externally-tangent rectangle of region is used as the mark of location of region.The location experiment is achieved with a false-acceptance rate of 7.1% and a false-rejection rate of 0% on Chinese bankcheck. 展开更多
关键词 定位算法 封装技术 图象识别 射线模式
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Nonlinear identification and characterization of structural joints based on vibration transmissibility 被引量:3
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作者 Liu Xin Sun Beibei +2 位作者 Li Lie Chen Jiandong Xue Fei 《Journal of Southeast University(English Edition)》 EI CAS 2018年第1期36-42,共7页
In order to investigate the nonlinear characteristics of structural joint,the experimental setup with a jointed mass system is established for dynamic characterization analysis and vibration prediction,and a correspon... In order to investigate the nonlinear characteristics of structural joint,the experimental setup with a jointed mass system is established for dynamic characterization analysis and vibration prediction,and a corresponding nonlinearity identification method is studied.First,the sine-sweep vibration test with different baseexcitation levels areapplied to the structural joint system to study the dominant modal of mass rigid motion.Then,based on t e harmonic balance method principle,t e measured vibration transmissibilities a e utilized for nonlinearity identification using different excitation levels.Experimental results show that nonlinear spring and damping force can be represented by a polynomial order approximation.The identified nonlinear stiffness and damping force can predict the system’s response,and they can reveal t e shifts of resonant frequency or damping due to discontinuity of contact mechanisms within a certain range. 展开更多
关键词 structural joint vibration transmissibility nonlinear identification harmonic balance method
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A recognition method of vibration parameter image based on improved immune negative selection algorithm for rotating machinery 被引量:4
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作者 窦唯 刘占生 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2009年第1期5-10,共6页
To overcome the limitations of traditional monitoring methods, based on vibration parameter image of rotating machinery, this paper presents an abnormality online monitoring method suitable for rotating machinery usin... To overcome the limitations of traditional monitoring methods, based on vibration parameter image of rotating machinery, this paper presents an abnormality online monitoring method suitable for rotating machinery using the negative selection mechanism of biology immune system. This method uses techniques of biology clone and learning mechanism to improve the negative selection algorithm to generate detectors possessing different monitoring radius, covers the abnormality space effectively, and avoids such problems as the low efficiency of generating detectors, etc. The result of an example applying the presented monitoring method shows that this method can solve the difficulty of obtaining fault samples preferably and extract the turbine state character effectively, it also can detect abnormality by causing various fault of the turbine and obtain the degree of abnormality accurately. The exact monitoring precision of abnormality indicates that this method is feasible and has better on-line quality, accuracy and robustness. 展开更多
关键词 artificial immune system negative selection algorithm abnormality monitor image recognition rotating machinery
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Filtering algorithm and direction identification in relative position estimation based on induction loop-cable 被引量:2
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作者 窦峰山 戴春辉 谢云德 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第1期112-121,共10页
A filtering algorithm and direction identification method are presented for the positioning system of the mid-speed maglev train. Considering the special structure of the mid-speed maglev train, the ground position es... A filtering algorithm and direction identification method are presented for the positioning system of the mid-speed maglev train. Considering the special structure of the mid-speed maglev train, the ground position estimation method is adopted for its traction system. As the train is running, the induction loop-cable receives the signal sent by the on-board antenna to detect the position and direction of the train. But the height of the on-board antenna relative to the loop-cable is highly vulnerable to the change of the suspension height and the magnetic field produced by the traction during traveling, which may lead to amplitude fluctuation of the received signal. Consequently, the position estimation may be inaccurate. Therefore, a discrete second-order nonlinear trackdifferentiator is proposed based on the boundary characteristic curves, and the new differentiator could also extract the running direction of the train for the traction system. The experimental results show that the tracking differentiator can effectively filter out the signal interference and can provide accurate direction signal. 展开更多
关键词 maglev train positioning system loop-cable tracking-differentiator (TD) direction identification
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Localization of pallets in warehouses using passive RFID system 被引量:2
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作者 周俊儒 张宏建 周洪亮 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第8期3017-3025,共9页
Warehouse operation has become a critical activity in supply chain. Position information of pallets is important in warehouse management which can enhance the efficiency of pallets picking and sortation. Radio frequen... Warehouse operation has become a critical activity in supply chain. Position information of pallets is important in warehouse management which can enhance the efficiency of pallets picking and sortation. Radio frequency identification(RFID) has been widely used in warehouse for item identifying. Meanwhile, RFID technology also has great potential for pallets localization which is underutilized in warehouse management. RFID-based checking-in and inventory systems have been applied in warehouse management by many enterprises. Localization approach is studied, which is compatible with existing RFID checking-in and inventory systems. A novel RFID localization approach is proposed for pallets checking-in. Phase variation of nearby tags was utilized to estimate the position of added pallets. A novel inventory localization approach combing angle of arrival(AOA) measurement and received signal strength(RSS) is also proposed for pallets inventory. Experiments were carried out using standard UHF passive RFID system. Experimental results show an acceptable localization accuracy which can satisfy the requirement of warehouse management. 展开更多
关键词 warehouse management radio frequency identification (RFID) LOCALIZATION tag phase
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Boosting the Expense and Performance of Ann/Hmm Approch for on-line Handwriting Recognition
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作者 李海峰 HAN Jiqing +2 位作者 Zheng Tieran Ma Lin Gallinari P 《High Technology Letters》 EI CAS 2003年第4期83-87,共5页
This paper focuses on a state sharing method for an artificial neural network (ANN) and hidden Markov model (HMM) hybrid on line handwriting recognition system. A modeling precision based distance measure is proposed ... This paper focuses on a state sharing method for an artificial neural network (ANN) and hidden Markov model (HMM) hybrid on line handwriting recognition system. A modeling precision based distance measure is proposed to describe similarity between two ANNs, which are used as HMM state models. Limiting maximum system performance loss, a minimum quantification error aimed hierarchical clustering algorithm is designed to choose the most representative models. The system performance is improved by about 1.5% while saving 40% of the system expense. About 92% of the performance may also be maintained while reducing 70% of system parameters. The suggested method is quite useful for designing pen based interface for various handheld devices. 展开更多
关键词 BOOSTING state sharing hierarchical clustering on line handwriting recognition
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Parameters identification of the compound cage rotor induction machine based on linearized Kalman filtering
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作者 王铁成 李伟力 孙建伟 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2003年第2期133-136,共4页
A mathematical model has been built up for compound cage rotor induction machine with the rotor resistance and leakage inductance in the model identified through Kalman filtering method. Using the identified parameter... A mathematical model has been built up for compound cage rotor induction machine with the rotor resistance and leakage inductance in the model identified through Kalman filtering method. Using the identified parameters, simulation studies are performed, and simulation results are compared with testing results. 展开更多
关键词 compound cage rotor parameter identification Kalman filter
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ENHANCED ENERGY-SAVING ANTICOLLISION ALGORITHMS WITH IMPROVING THROUGHPUT FOR RFID SYSTEM
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作者 Luo Zhiyong Jiang Jing Wang Ping 《Journal of Electronics(China)》 2013年第1期40-48,共9页
Tag collision algorithm is a key issue for energy saving and throughput with Radio Frequency IDentification (RFID) system more popular in sensing infrastructure of covering wider area on a large scale. Exploiting low ... Tag collision algorithm is a key issue for energy saving and throughput with Radio Frequency IDentification (RFID) system more popular in sensing infrastructure of covering wider area on a large scale. Exploiting low energy consumption strategy would enable longer operational life of tags and reader with battery energy supply. And improving throughput is required on a large scale to preserve the capability of the correct reception. Therefore, this paper proposes an enhanced anti-collision algorithm called Dynamic Slotted with Muting (DSM), which uses multiple slots within a frame per node in a binary tree and takes tag estimation function to optimize the number of slots, and adds a mute command to put identified tags silence. The performance of the proposed algorithm is analytically provided, and simulation results show that DSM saves more than 40% energy consumptions both at reader and tags, and improves more than 35% throughput compared to the existing algorithms. Thus our algorithm is demonstrated to perform efficient energy savings at reader and tags with throughput improvement. 展开更多
关键词 Anti-collision algorithm Radio Frequency IDentification (RFID) Energy consumption THROUGHPUT Query tree
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3D Object Visual Tracking for the 220 kV/330 kV High-Voltage Live-Line Insulator Cleaning Robot
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作者 张健 杨汝清 《Journal of Donghua University(English Edition)》 EI CAS 2009年第3期264-269,共6页
The 3D object visual tracking problem is studied for the robot vision system of the 220kV/330kV high-voltage live-line insulator cleaning robot. The SUSAN Edge based Scale Invariant Feature (SESIF) algorithm based 3D ... The 3D object visual tracking problem is studied for the robot vision system of the 220kV/330kV high-voltage live-line insulator cleaning robot. The SUSAN Edge based Scale Invariant Feature (SESIF) algorithm based 3D objects visual tracking is achieved in three stages: the first frame stage,tracking stage,and recovering stage. An SESIF based objects recognition algorithm is proposed to find initial location at both the first frame stage and recovering stage. An SESIF and Lie group based visual tracking algorithm is used to track 3D object. Experiments verify the algorithm's robustness. This algorithm will be used in the second generation of the 220kV/330kV high-voltage live-line insulator cleaning robot. 展开更多
关键词 HIGH-VOLTAGE live-line ROBOTICS SUSAN Edge based Scale Invariant Feature SESIF) object recognition visual tracking Lie group
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基于激光扫描技术的打磨工具精准对位
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作者 槐创锋 黄升 +1 位作者 黄涛 尚鲁强 《激光与光电子学进展》 CSCD 北大核心 2020年第23期289-296,共8页
针对机车自动化打磨系统对位不精准、打磨厚度不均匀的问题,提出了一种基于激光扫描技术的打磨工具中轴线对位打磨点法线方向的算法。首先,计算线激光传感器扫描获取的待打磨件三维模型法向量,并将6种获取法线的算法进行对比,用效果最... 针对机车自动化打磨系统对位不精准、打磨厚度不均匀的问题,提出了一种基于激光扫描技术的打磨工具中轴线对位打磨点法线方向的算法。首先,计算线激光传感器扫描获取的待打磨件三维模型法向量,并将6种获取法线的算法进行对比,用效果最优的算法计算模型上各点的法线坐标;然后,通过手眼标定使法线坐标与打磨工具中轴线坐标可相互转换,并利用离线编程使两者实现精准对位;最后,建立打磨模型,计算理想的打磨厚度,测量精准对位和未精准对位的打磨厚度。实验结果表明,与未精准对位的算法相比,本算法能很好地解决打磨厚度不均匀的问题,且打磨结果与理想效果接近。 展开更多
关键词 激光技术 自动化打磨 精准对位 法线识别 打磨厚度
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Dynamic Bayesian identification of mechanical parameters of multi-cell curve box girder based on conjugate gradient theory
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作者 ZHANG Jian ZHOU ChuWei LIN Jing 《Science China(Technological Sciences)》 SCIE EI CAS 2012年第4期1057-1065,共9页
For multi-cell curve box girder, the finite strip governing equation was derived on the basis of Novozhilov theory and orthogonal property of harmonious function series. Dynamic Bayesian error function of mechanical p... For multi-cell curve box girder, the finite strip governing equation was derived on the basis of Novozhilov theory and orthogonal property of harmonious function series. Dynamic Bayesian error function of mechanical parameters of multi-cell curve box girder was achieved with Bayesian statistical theory. The corresponding formulas of dynamic Bayesian expectation and variance were obtained. After the one-dimensional optimization search method for the automatic determination of step length of the mechanical parameter was put forward, the optimization identification calculative formulas were also obtained by adopting conjugate gradient method. Then the steps of dynamic Bayesian identification of mechanical parameters of multi-cell curve box girder were stated in detail. Through analysis of a classic example, the dynamic Bayesian identification processes of mechanical parameters are steadily convergent to the true values, which proves that dynamic Bayesian theory and conjugate gradient theory are suitable for the identification calculation and the compiled procedure is correct. It is of significance that the foreknown information of mechanical parameters should be set with reliable practical engineering experiences instead of arbitrary selection. 展开更多
关键词 mechanical parameters multi-cell curve box girder Bayesian identification conjugate gradient theory
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Multifractal methods for rapeseed nitrogen nutrition qualitative diagnosis modeling
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作者 Jian-Hui Li Fang Wang +2 位作者 Jin-Wei Li Rui-Biao Zou Gui-Ping Liao 《International Journal of Biomathematics》 2016年第4期285-297,共13页
Nutrition diagnosis plays a key role in the crop's growth, which has mainly been car- ried out in the field by agricultural workers. Currently, automatic nutrition recognition technologies have been widely used in th... Nutrition diagnosis plays a key role in the crop's growth, which has mainly been car- ried out in the field by agricultural workers. Currently, automatic nutrition recognition technologies have been widely used in this field. A procedure is proposed in this paper to diagnose nitrogen nutrition non-destructively for rapeseed qualitatively based on the multifractal theory. Twelve texture parameters are given by the method of multifractal detrended fluctuation (MF-DFA), which contains six generalized Hurst exponents and six relative multifractal parameters that are used as features of the rapeseed leaf images for identifying the two nitrogen levels, namely, the N-mezzo and the N-wane. For the base leaves, central leaves and top leaves of the rapeseed plant and the three-section mixed samples, three parameters combinations are selected to conduct the work. Five classifiers of Fisher's linear discriminant algorithm (LDA), extreme learning machine (ELM), support vector machine and kernel method (SVMKM), random decision forests (RF) and K-nearest neighbor algorithm (KNN) are employed to calculate the diagno- sis accuracy. An interesting finding is that the best diagnose accuracy is from the base leaves of the rapeseed plant. It is explained that the base leaf is the most sensitive to the nitrogen deficiency. The diagnose effect by the base leaves samples is outshining the existing result significantly for the same leaves samples. For the mixed samples, the aver- aged discriminant accuracy reaches 97.12% and 97.56% by SVMKM and RF methods with the 10-fold cross-validation respectively. The resulting high accuracy on N-levels identification shows the feasibility and efficiency of our method. 展开更多
关键词 Rapeseed leaf image nitrogen diagnosis multifractal detrended fluctuationanalysis classifiers.
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