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Preprocessing method of night vision image application in apple harvesting robot 被引量:4
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作者 Weikuan Jia Yuanjie Zheng +3 位作者 De’an Zhao Xiang Yin Xiaoyang Liu Ruicheng Du 《International Journal of Agricultural and Biological Engineering》 SCIE EI CAS 2018年第2期158-163,共6页
Due to the low working efficiency of apple harvesting robots,there is still a long way to go for commercialization.The machine performance and extended operating time are the two research aspects for improving efficie... Due to the low working efficiency of apple harvesting robots,there is still a long way to go for commercialization.The machine performance and extended operating time are the two research aspects for improving efficiencies of harvesting robots,this study focused on the extended operating time and proposed a round-the-clock operation mode.Due to the influences of light,temperature,humidity,etc.,the working environment at night is relatively complex,and thus restricts the operating efficiency of the apple harvesting robot.Three different artificial light sources(incandescent lamp,fluorescent lamp,and LED lights)were selected for auxiliary light according to certain rules so that the apple night vision images could be captured.In addition,by color analysis,night and natural light images were compared to find out the color characteristics of the night vision images,and intuitive visual and difference image methods were used to analyze the noise characteristics.The results showed that the incandescent lamp is the best artificial auxiliary light for apple harvesting robots working at night,and the type of noise contained in apple night vision images is Gaussian noise mixed with some salt and pepper noise.The preprocessing method can provide a theoretical and technical reference for subsequent image processing. 展开更多
关键词 apple harvesting robot night vision image preprocessing method color analysis noise analysis
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Night Vision Object Tracking System Using Correlation Aware LSTM-Based Modified Yolo Algorithm
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作者 R.Anandha Murugan B.Sathyabama 《Intelligent Automation & Soft Computing》 SCIE 2023年第4期353-368,共16页
Improved picture quality is critical to the effectiveness of object recog-nition and tracking.The consistency of those photos is impacted by night-video systems because the contrast between high-profile items and diffe... Improved picture quality is critical to the effectiveness of object recog-nition and tracking.The consistency of those photos is impacted by night-video systems because the contrast between high-profile items and different atmospheric conditions,such as mist,fog,dust etc.The pictures then shift in intensity,colour,polarity and consistency.A general challenge for computer vision analyses lies in the horrid appearance of night images in arbitrary illumination and ambient envir-onments.In recent years,target recognition techniques focused on deep learning and machine learning have become standard algorithms for object detection with the exponential growth of computer performance capabilities.However,the iden-tification of objects in the night world also poses further problems because of the distorted backdrop and dim light.The Correlation aware LSTM based YOLO(You Look Only Once)classifier method for exact object recognition and deter-mining its properties under night vision was a major inspiration for this work.In order to create virtual target sets similar to daily environments,we employ night images as inputs;and to obtain high enhanced image using histogram based enhancement and iterative wienerfilter for removing the noise in the image.The process of the feature extraction and feature selection was done for electing the potential features using the Adaptive internal linear embedding(AILE)and uplift linear discriminant analysis(ULDA).The region of interest mask can be segmen-ted using the Recurrent-Phase Level set Segmentation.Finally,we use deep con-volution feature fusion and region of interest pooling to integrate the presently extremely sophisticated quicker Long short term memory based(LSTM)with YOLO method for object tracking system.A range of experimentalfindings demonstrate that our technique achieves high average accuracy with a precision of 99.7%for object detection of SSAN datasets that is considerably more than that of the other standard object detection mechanism.Our approach may therefore satisfy the true demands of night scene target detection applications.We very much believe that our method will help future research. 展开更多
关键词 Object monitoring night vision image SSAN dataset adaptive internal linear embedding uplift linear discriminant analysis recurrent-phase level set segmentation correlation aware LSTM based yolo classifier algorithm
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Center of rotation estimation for rocket nozzle by infrared reflective makers and image sequences
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作者 张灵飞 陈刚 +1 位作者 叶东 车仁生 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2011年第2期56-60,共5页
The determination of an accurate center of rotation of rocket motor nozzle or other object to be measured is of great interest across a wide range of applications,such as rocket,missile,robotics,industry,spaceflight,a... The determination of an accurate center of rotation of rocket motor nozzle or other object to be measured is of great interest across a wide range of applications,such as rocket,missile,robotics,industry,spaceflight,aviation and human motion analysis fields,particularly for clinical gait analysis.A new approach was proposed to estimate the moving objects' instantaneous center of rotation and other motion parameters.The new method assumes that the two segment of object to be measured are rigid body which rotates around a center of rotation between each other relatively.The center of rotation varies with time in the global coordinate system but is fixed in the local coordinate system attached to each segment.The models of rocket motor nozzle and its movement were established.The arbitrary moving object's corresponding to motion equations were deduced,and the least square closed-form solutions of the object's motion parameters were figured out.It is assumed that the two high speed CCD cameras mounted on the 750 nm infrared(IR) filter are synchronized and calibrated in advance.The virtual simulation experiment using 3D coordinates of markers was conducted by synchronized stereo image sequences based on 6-DOF motion platform and the experimental results prove the feasibility of our algorithm.The test results show that the precision of x,y,z component on center of rotation is up to 0.14 mm,0.13 mm,0.15 mm. 展开更多
关键词 rocket motor nozzle center of rotation stereo vision image sequence IR reflective marker high speed CCD camera
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Three-dimensional motion parameters estimation from stereo image sequences based on infrared reflective markers
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作者 张灵飞 陈刚 +1 位作者 叶东 车仁生 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2011年第4期139-143,共5页
In this paper,an innovative 3D motion parameters estimation method from stereo image sequences based on infrared(IR) reflective markers is presented.It was assumed that two high speed CCD cameras had been calibrated p... In this paper,an innovative 3D motion parameters estimation method from stereo image sequences based on infrared(IR) reflective markers is presented.It was assumed that two high speed CCD cameras had been calibrated previously.The method consists of the following steps:1) the coordinate of several markers and depth map for each stereo pair was determined from the sequences of stereo images by relations of markers' coordinate the correspondence between markers was established,2) the 3D motion parameters of the target was computed based upon the matched markers' coordinate,and 3) translated 3D motion parameters estimation into the problem of least square according to the movement model of the object to be measured.Without using line,curve or corner correspondence,this method can calculate the depth of these markers feature easily and quickly in contrast to traditional approaches.The two CCD cameras work on 200 f/s,and each processing cost time is about 3 ms.It was found that,by using several markers and a large number of stereo images,this method can improve the computational speed,robustness and numerical accuracy of the motion parameters in comparison with traditional methods.The virtual simulation experiment was conducted using synthesized stereo image sequences based on 6-DOF motion platform and the experimental results proved the validity of our approach and showed that the translation and rotation precision is up to 0.1 mm and 0.1°. 展开更多
关键词 IR reflective marker 3D motion parameters stereo vision image sequence high speed CCD camera IR filter
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Decoding brain responses to pixelized images in the primary visual cortex: implications for visual cortical prostheses 被引量:4
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作者 Bing-bing Guo Xiao-lin Zheng +4 位作者 Zhen-gang Lu Xing Wang Zheng-qin Yin Wen-sheng Hou Ming Meng 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第10期1622-1627,共6页
Visual cortical prostheses have the potential to restore partial vision. Still limited by the low-resolution visual percepts provided by visual cortical prostheses, implant wearers can currently only "see" pixelized... Visual cortical prostheses have the potential to restore partial vision. Still limited by the low-resolution visual percepts provided by visual cortical prostheses, implant wearers can currently only "see" pixelized images, and how to obtain the specific brain responses to different pixelized images in the primary visual cortex(the implant area) is still unknown. We conducted a functional magnetic resonance imaging experiment on normal human participants to investigate the brain activation patterns in response to 18 different pixelized images. There were 100 voxels in the brain activation pattern that were selected from the primary visual cortex, and voxel size was 4 mm × 4 mm × 4 mm. Multi-voxel pattern analysis was used to test if these 18 different brain activation patterns were specific. We chose a Linear Support Vector Machine(LSVM) as the classifier in this study. The results showed that the classification accuracies of different brain activation patterns were significantly above chance level, which suggests that the classifier can successfully distinguish the brain activation patterns. Our results suggest that the specific brain activation patterns to different pixelized images can be obtained in the primary visual cortex using a 4 mm × 4 mm × 4 mm voxel size and a 100-voxel pattern. 展开更多
关键词 nerve regeneration primary visual cortex electrical stimulation visual cortical prosthesis low resolution vision pixelized image functional magnetic resonance imaging voxel size neural regeneration brain activation pattern
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Novel region-based image compression method based on spiking cortical model
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作者 Rongchang Zhao Yide Ma 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第1期161-171,共11页
To get the high compression ratio as well as the high-quality reconstructed image, an effective image compression scheme named irregular segmentation region coding based on spiking cortical model(ISRCS) is presented... To get the high compression ratio as well as the high-quality reconstructed image, an effective image compression scheme named irregular segmentation region coding based on spiking cortical model(ISRCS) is presented. This scheme is region-based and mainly focuses on two issues. Firstly, an appropriate segmentation algorithm is developed to partition an image into some irregular regions and tidy contours, where the crucial regions corresponding to objects are retained and a lot of tiny parts are eliminated. The irregular regions and contours are coded using different methods respectively in the next step. The other issue is the coding method of contours where an efficient and novel chain code is employed. This scheme tries to find a compromise between the quality of reconstructed images and the compression ratio. Some principles and experiments are conducted and the results show its higher performance compared with other compression technologies, in terms of higher quality of reconstructed images, higher compression ratio and less time consuming. 展开更多
关键词 data compaction and compression image processing and computer vision region-based image coding neural network
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Employment of predictive search algorithm in digital image correlation
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作者 马志峰 王昊 韩福海 《Journal of Beijing Institute of Technology》 EI CAS 2014年第2期254-259,共6页
A predictive search algorithm to estimate the size and direction of displacement vectors was presented.The algorithm decreased the time of calculating the displacement of each pixel.In addition,the updating reference ... A predictive search algorithm to estimate the size and direction of displacement vectors was presented.The algorithm decreased the time of calculating the displacement of each pixel.In addition,the updating reference image scheme was used to update the reference image and to decrease the computation time when the displacement was larger than a certain number.In this way,the search range and computational complexity were cut down,and less EMS memory was occupied.The capability of proposed search algorithm was then verified by the results of both computer simulation and experiments.The results showed that the algorithm could improve the efficiency of correlation method and satisfy the accuracy requirement for practical displacement measuring. 展开更多
关键词 machine vision predictive search algorithm digital image correlation sub-pixel displacement measurement
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Deep Learning Blockchain Integration Framework for Ureteropelvic Junction Obstruction Diagnosis Using Ultrasound Images
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作者 Yu Guan Pengceng Wen +2 位作者 Jianqiang Li Jinli Zhang Xianghui Xie 《Tsinghua Science and Technology》 SCIE EI CAS CSCD 2024年第1期1-12,共12页
UreteroPelvic Junction Obstruction(UPJO)is a common hydronephrosis disease in children that can result in an even progressive loss of renal function.Ultrasonography is an economical,radiationless,noninvasive,and high ... UreteroPelvic Junction Obstruction(UPJO)is a common hydronephrosis disease in children that can result in an even progressive loss of renal function.Ultrasonography is an economical,radiationless,noninvasive,and high noise preliminary diagnostic step for UPJO.Artificial intelligence has been widely applied to medical fields and can greatly assist doctors'diagnostic abilities.The demand for a highly secure network environment in transferring electronic medical data online,therefore,has led to the development of blockchain technology.In this study,we built and tested a framework that integrates a deep learning diagnosis model with blockchain technology.Our diagnosis model is a combination of an attention-based pyramid semantic segmentation network and a discrete wavelet transformation-processed residual classification network.We also compared the performance between benchmark models and our models.Our diagnosis model outperformed benchmarks on the segmentation task and classification task with MloU=87.93,MPA=93.52,and accuracy=91.77%.For the blockchain system,we applied the InterPlanetary File System protocol to build a secure and private sharing environment.This framework can automatically grade the severity of UPJO using ultrasound images,guarantee secure medical data sharing,assist in doctors'diagnostic ability,relieve patients'burden,and provide technical support for future federated learning and linkage of the Internet of Medical Things(loMT). 展开更多
关键词 data mining image processing and computer vision machine learning medical information systems
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CMOS vision sensor with fully digital image process integrated into low power 1/8-inch chip
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作者 金湘亮 刘志碧 陈杰 《Chinese Optics Letters》 SCIE EI CAS CSCD 2010年第3期282-285,共4页
A digital still camera image processing system on a chip, different from the video camera system, is pre- sented for mobile phone to reduce the power consumption and size. A new color interpolation algorithm is propos... A digital still camera image processing system on a chip, different from the video camera system, is pre- sented for mobile phone to reduce the power consumption and size. A new color interpolation algorithm is proposed to enhance the image quality. The system can also process fixed patten noise (FPN) reduction, color correction, gamma correction, RGB/YUV space transfer, etc. The chip is controlled by sensor regis- ters by inter-integrated circuit (I2C) interface. The voltage for both the front-end analog and the pad cir- cuits is 2.8 V, and the volatge for the image signal processing is 1.8 V. The chip running under the external 13.5-MHz clock has a video data rate of 30 frames/s and the measured power dissipation is about 75 roW. 展开更多
关键词 CMOS vision sensor with fully digital image process integrated into low power 1/8-inch chip RATE RGB
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Comparisons of JOULE 1 rocket thermospheric wind observations in high latitudes with GITM simulations
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作者 DENG Yue LARSEN Miguel F +1 位作者 RIDLEY Aaron J ZHAN TianYu 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2017年第3期412-418,共7页
4 Summary and conclusion The JOULE sounding rocket 1 experiment was carried out at Poker Flat Research Range in Alaska around 1200 UT on March 27th,2003 with two instrumented rockets and one chemical tracer rocket.Fro... 4 Summary and conclusion The JOULE sounding rocket 1 experiment was carried out at Poker Flat Research Range in Alaska around 1200 UT on March 27th,2003 with two instrumented rockets and one chemical tracer rocket.From the released TMA trails,neutral wind measurements from approximately 85 to 160 km altitude showed a vertically propagating wave and a jet structure around 120 km altitude.Large shears appeared at the bottom side of the jet with Richardson numbers close to or smaller than the critical value of 0.25,which implies the possible existence of Kelvin-Helmholtz instabilities caused by the vertical shear in the fast flows. 展开更多
关键词 target tracking parallel vision processor MRID skipping searching image processing
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