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Optoelectronics Letters 2023年第11期19卷 686-692页

作者： QIAO Zhifeng FU Kang LIU Zhenzhong Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control School of Mechanical EngineeringTianjin University of TechnologyTianjin300384China National Demonstration Center for Experimental Mechanical and Electrical Engineering Education Tianjin University of TechnologyTianjin300384China

Aiming at the problem of poor accuracy consistency of large sections’docking assembly,an automatic docking method using multiple laser trackers to measure the position and posture of the docking sections in real time was proposed.In the solution of the pose of the docking section,real-time pose measurement of the docking section was realized by establishing a global coordinate system and a coordinate fusion method of three or more laser trackers.In the automatic control of the docking process,the real-time communication protocol and the circular negative feedback control strategy of measurement-adjustment-re-measurement are adopted,and the fully-automated docking of large sections is realized.Finally,an experimental verification system was set up,and the docking of the large-scale section reduction models was realized under the requirements of docking accuracy,and the effectiveness of the automatic docking scheme was successfully verified.

关键词： coordinate deviation system

Research of line-of-sight angle on aero-optic imaging deviation for vehicles flying at 40—60 km

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Optoelectronics Letters 2023年第4期19卷 242-247页

作者： XU Liang ZHAO Shiwei WANG Tao Tianjin Key Laboratory of Complex Control Theory and Application School of Electronic Engineering and AutomationTianjin University of TechnologyTianjin 300384China Foreign Cooperation Projects Department PetroChina Dagang Oilfield CompanyTianjin 300280China

Aero-optical imaging deviation is a kind of optical effect,aiming at a conical aircraft.This paper analyzes the influence of the aircraft on the imaging deviation with the change of altitude and line-of-sight angle.In this paper,the relationships between imaging deviation and altitude as well as line-of-sight angle are analyzed,and the coupling relationship between altitude and line-of-sight angle is studied.We give the imaging deviation results of 5°—75°line-of-sight angle.The analysis shows that when the line-of-sight angle is in the range of 5°—35°,the imaging deviation is more sensitive,while the line-of-sight angle is in the range of 35°—75°,the imaging deviation is relatively flat,and the imaging deviation does not gradually decrease with the increase of line-of-sight angle,but there is a turning point in the middle of 5°—75°.The imaging deviation decreases first and then increases,and the turning point of line-of-sight angle is closely related to height.

关键词： deviation angle turning

Aero-optic imaging deviation prediction based on ISSA-ELM

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光电子快报:英文版 2023年第7期19卷 425-431页

作者： XU Liang ZHAO Shiwei WANG Tao Tianjin Key Laboratory for Control Theory&Applications in Complicated Systems School of Electrical Engineering and AutomationTianjin University of TechnologyTianjin 300384China School of Intelligent Engineering Sun Yat-sen UniversityGuangzhou 510275China

When the aircraft is moving at high speed in the atmosphere,aero-optical imaging deviation will appear due to the influence of aero-optical effect.In order to achieve real-time compensation during the flight of the aircraft,it is necessary to analyze and predict the obtained imaging deviation data.In order to improve the search speed and accuracy of the prediction algorithm and the ability to jump out of local optimum,in this paper,an improved sparrow search algorithm optimized extreme learning machine(ISSA-ELM) neural network model is proposed to predict the aero-optical imagine deviation.Finally,the performance of ISSA-ELM,ELM neural network and SSA-ELM neural network was tested.The results showed that compared with ELM and SSA-ELM algorithms,the convergence speed of ISSA-ELM was significantly enhanced,and the accuracy of data prediction was also significantly improved.

关键词： effect. deviation extreme

The effects of simultaneous operation on dissociated vertical deviation with horizontal and torsional strabismus

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International Journal of Ophthalmology(English edition) 2020年第4期13卷 637-642页

作者： Lu-Qin Wan Xiao-Mei Wan Hua-Qing Gong Li-Xin Xie Medical College of Qingdao University Qingdao 266000Shandong ProvinceChina Qingdao Eye Hospital Shandong Eye InstituteShandong First Medical University&Shandong Academy of Medical SciencesQingdao 266071Shandong ProvinceChina

AIM: To investigate the therapeutic effects of simultaneous horizontal and vertical operations on dissociated vertical deviation(DVD) associated with other deviations.METHODS: Forty-five cases of DVD with horizontal and torsional strabismus underwent combined operation were collected retrospectively. All clinical records were analyzed. All patients were followed up for 6 to 24 mo. Wilcoxon signed-ranks test was performed to evaluate the changes of vertical and horizontal deviation. χ~2 test was used to evaluate the changes of binocular visual function. RESULTS: Forty-five cases included 36 patients with intermittent exotropia and binocular inferior oblique overaction(IOOA), 5 patients with concomitant esotropia and binocular IOOA, 4 patients with intermittent exotropia and monocular superior oblique palsy. The superior rectus recession(SRR) combined with horizontal rectus recession and the myectomy of inferior oblique or anterior transposition were operated simultaneously to correct all types of strabismus. There were 43 cases who achieved normal eye position in vertical direction, while 2 cases were with undercorrection of 5~Δ to 6~Δ. In patients with horizontal strabismus, 2 cases of exotropia were with overcorrection of 6~Δ to 8~Δ, 1 case of esotropia was with undercorrection of 6~Δ, and 1 case of monocular superior oblique palsy with compensatory head posture was not significantly improved. The binocular visual function of most patients recovered after operation. The difference of the binocular visual function and eye position were significant compared with that before operation(P<0.05).CONCLUSION: The simultaneous operation on DVD with horizontal and torsional strabismus is successful.

关键词： dissociated vertical deviation inferior oblique overaction strabismus operation

Review on cochlear implant electrode array tip fold-over and scalar deviation

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Journal of Otology 2019年第3期14卷 94-100页

作者： Anandhan Dhanasingh Claude Jolly MED-EL Medical Electronics GmbH

Objective: Determine the occurrence rate of cochlear implant (CI) electrode tip fold-over and electrode scalar deviation as reported in patient cases with different commercial electrode types. Data-sources: PubMed search for identifying peer-reviewed articles published till 2018 on CI electrode tip fold-over and scalar deviation. Key-words for searching were “Cochlear electrode tip fold-over”,“Cochlear electrode scalar position” and “Cochlear electrode scalar location”. Articles-selection: Only if electrode related issues were investigated in patient cases. 38 articles met the inclusion-criteria. Results: 13 articles on electrode tip fold-over issue covering 3177 implanted ears, out of which 50 ears were identified with electrode tip fold-over with an occurrence rate of 1.57%. Out of 50 ears, 43 were implanted with pre-curved electrodes and the remaining 7 with lateral-wall electrodes. One article reported on both tip fold-over and scalar deviation. 26 articles reported on the electrode scalar deviation covering an overall number of 2046 ears out of which, 458 were identified with electrode scalar deviation at a rate of 22.38%. After removing the studies that did not report on the number of electrodes per electrode type, it was 1324 ears implanted with pre-curved electrode and 507 ears with lateral-wall electrode. Out of 1324 pre-curved electrode implanted ears, 424 were reported with scalar deviation making an occurrence rate of 32%. Out of 507 lateral-wall electrode implanted ears, 43 were associated with scalar deviation at an occurrence rate of 6.7%. Conclusion: This literature review revealing the fact of higher rate of electrode insertion trauma associated with pre-curved electrode type irrespective of CI brand is one step closer to obsolete it from the clinical practice in the interest of patient's cochlear health.

关键词： Electrode tip fold-over Scalar deviation Pre-curved electrode Straight electrode

deviation Prevention Ability of Rollers in Continuous Annealing Furnace and Application

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Journal of Iron and Steel Research(International) 2012年第12期19卷 8-13页

作者： ZHANG Yan YANG Quan HE An-rui YAO Xi-jiang GUO De-fu National Engineering Research Center of Advanced Rolling University of Science andTechnology Beijing Beijing 100083 China

In order to reduce the strip deviation in the practical production procedure in the continuous annealing fur- nace, a dynamic simulation model was built through finite element method （FEM） to conduct the quantification cal- culation of the effect of regular roller contour types on strip deviation. The result reveals that comparing to the flat roller, forward roller contour can prevent the strip deviation to some degree. In terms of prevention ability, double- taper roller is the strongest, single-taper roller and crown roller are less stronger; and more roller contour values raise the prevention ability. Accordingly, optimization method was applied to continuous annealing furnace, and it largely reduced accidents such as strip break and limited speed that are caused by the deviation.

关键词： strip deviation continuous annealing furnace dynamic simulation roller contour

Perceptual Gradient Similarity deviation for Full Reference Image Quality Assessment

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Computers, Materials & Continua 2018年第9期56卷 501-515页

作者： Manyu Jin Tao Wang Zexuan Ji Xiaobo Shen School of Computer Science and Engineering Nanjing University of Science and TechnologyNanjing210094China School of Computer Science and Engineering Nanyang Technology University639798Singapore

Perceptual image quality assessment(IQA)is one of the most indispensable yet challenging problems in image processing and computer vision.It is quite necessary to develop automatic and efficient approaches that can accurately predict perceptual image quality consistently with human subjective evaluation.To further improve the prediction accuracy for the distortion of color images,in this paper,we propose a novel effective and efficient IQA model,called perceptual gradient similarity deviation(PGSD).Based on the gradient magnitude similarity,we proposed a gradient direction selection method to automatically determine the pixel-wise perceptual gradient.The luminance and chrominance channels are both took into account to characterize the quality degradation caused by intensity and color distortions.Finally,a multi-scale strategy is utilized and pooled with different weights to incorporate image details at different resolutions.Experimental results on LIVE,CSIQ and TID2013 databases demonstrate the superior performances of the proposed algorithm.

关键词： Image quality assessment full reference perceptual gradient similarity multi-scale standard deviation pooling

BOREAL SUMMER CLIMATOLOGY AND STANDARD deviation IN GLOBAL LOW-FREQUENCY STREAMFUNCTION FIELDS AT 200 hPa

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Journal of Tropical Meteorology 2019年第2期25卷 153-161页

作者：季悦李艳杰吴志伟 Key Laboratory of Meteorology Disaster Ministry of Education (KLME)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD) Nanjing University of Information Science and Technology State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Institute of Atmospheric Sciences Fudan University

Based on NCEP/NCAR DOE daily reanalysis dataset during 1980-2015, this study investigates the boreal summer climatology and standard deviation of streamfunction in different low frequency periods(including 10-30 days,30-60 days and more than 60 days) at 200 hPa. Distinctions in the characteristics in different periods are emphasized. It is found that the distribution of streamfunction on the timescale longer than 60 days is mainly zonal symmetric,accompanied by strong variability in the Northern Hemisphere subtropical jet streams. For the 10-30-day timescale, it reflects the zonal fluctuating structure in the middle and high latitudes and large variability in the Southern Hemisphere.Tropical quadrupole structure is observed on the 30-60-day timescale in climatology. Besides, a relative weak standard deviation is also found in this period. This work provides basic knowledge on climatology and variability in low-frequency streamfunction, which has not been fully illustrated in previous studies.

关键词： low-frequency streamfunction boreal summer climatology standard deviation

Computation and analysis of aero-optic imaging deviation of a blunt nosed aircraft with Mach number 0.5—3

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Optoelectronics Letters 2023年第1期19卷 55-59页

作者： XU Liang ZHAO Shiwei XUE Wei WANG Tao Tianjin Key Laboratory for Control Theory&Applications in Complicated Systems School of Electrical Engineering and AutomationTianjin University of TechnologyTianjin300384China China Academy of Aerospace Science and Innovation Beijing100083China School of Intelligent Engineering Sun Yat-sen UniversityGuangzhou510275China

Aero-optic imaging is a kind of optical effect,which describes the imaging deviation on the imaging plane.In this paper,the effect of the change of Mach number of blunt aircraft on the aero-optic imaging deviation is studied.The imaging deviations of Mach number 0.5—3 are analyzed systematically.The results show that with the increase of Mach number,imaging deviation increases gradually,and the increase rate is gradually slow.Imaging deviation slope decreases gradually with the increase of Mach number,and gradually tends to be zero,suggesting that imaging deviation is not sensitive to the change of the larger Mach number.In other words,the Mach number of smaller changes can lead to larger imaging deviation.As the Mach number of the aircraft increases,the slope of the imaging offset tends to be closer and closer to 0.When the Mach number of the aircraft increases to a certain extent,the change of the imaging offset will not have much influence.Therefore,in order to reduce the impact of flight speed on imaging migration,the aircraft should fly at a higher Mach number.

关键词： deviation closer number

Welding deviation detection method based on weld pool image contour features

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China Welding 2019年第2期28卷 35-44页

作者：朱彦军吴志生李科杨培新 School of Materials Science and Engineering Taiyuan University of Science and Technology Taiyuan 030024 China Shanxi Sanyang Refrigeration Service Co. Ltd. Taiyuan 030024 China

Automatic on-line detection of welding deviation based on machine vision is one of the key technologies of arc welding robot tracking welding,in which obtaining high quality weld pool image and accurate welding deviation detection algorithm are two important steps of tracking welding.Through the research and analysis of the weld pool image of gas metal arc welding(GMAW),it was found that the weld pool contains abundant welding information.First,the average gray value of the weld pool image can reflect the interference degree of arc to weld pool image and the heat input of welding process.Secondly,the tip of the weld pool image contour can reflect the center of the groove gap.Finally,the horizontal distance between the center coordinate of the wire contour and the tip coordinate of the weld pool image contour can reflect the welding deviation.On the basis of analyzing the characteristics of weld pool image,this paper proposes a new method of weld seam deviation detection,which includes the collection of weld pool image,image preprocessing,contour extraction and deviation calculation.The results of the tests and analyses showed that the maximum error of the on-line welding deviation obtained was about 2 pixels(0.17 mm)when the welding speed was≤60 cm/min,and the algorithm was stable enough to meet the requirements of real-time deviation detection for I-groove butt welding.The method can be applied to the on-line automatic welding deviation detection of arc welding robot.

关键词： I-groove weld pool image deviation detection algorithm