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Automated identification of retinopathy of prematurity by image-based deep learning

Eye and Vision 2020年第4期7卷 379-390页

作者： Yan Tong Wei Lu Qin-qin Deng changzheng chen Yin Shen Eye Center Renmin Hospital of Wuhan UniversityWuhan 430060HubeiChina Medical Research Institute Wuhan UniversityWuhanHubeiChina

Background:Retinopathy of prematurity(ROP)is a leading cause of childhood blindness worldwide but can be a treatable retinal disease with appropriate and timely *** study was performed to develop a robust intelligent system based on deep learning to automatically classify the severity of ROP from fundus images and detect the stage of ROP and presence of plus disease to enable automated diagnosis and further ***:A total of 36,231 fundus images were labeled by 13 licensed retinal experts.A 101-layer convolutional neural network(ResNet)and a faster region-based convolutional neural network(Faster-RCNN)were trained for image classification and *** applied a 10-fold cross-validation method to train and optimize our *** accuracy,sensitivity,and specificity were assessed in a four-degree classification task to evaluate the performance of the intelligent *** performance of the system was compared with results obtained by two retinal ***,the system was designed to detect the stage of ROP and presence of plus disease as well as to highlight lesion regions based on an object detection network using ***:The system achieved an accuracy of 0.903 for the ROP severity ***,the accuracies in discriminating normal,mild,semi-urgent,and urgent were 0.883,0.900,0.957,and 0.870,respectively;the corresponding accuracies of the two experts were 0.902 and ***,our model achieved an accuracy of 0.957 for detecting the stage of ROP and 0.896 for detecting plus disease;the accuracies in discriminating stage I to stage V were 0.876,0.942,0.968,0.998 and 0.999,***:Our system was able to detect ROP and differentiate four-level classification fundus images with high accuracy and *** performance of the system was comparable to or better than that of human experts,demonstrating that this system could be used to support clinical decisions.

关键词： Deep learning Retinopathy of prematurity Artificial intelligence Fundus image

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Filter Connected with Three-way Cock in Remove of the Vehicle in Triamcinolone Acetonide

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眼科学报 2006年第3期22卷 156-159,165页

作者： Lei Du Yiqiao Xing changzheng chen Department of Ophthalmology Renmin Hospital Wuhan University Wuhan 430060 China.

Purpose: To evaluate the clinical effect of 5-μm pore filter connected with three-way cock by removing the vehicle in triamcinolone acetonide(TA) suspension. Methods: Through 5-μm pore filter connected with three-way cock, TA suspension was replaced by intraocular irrigating solution. The new suspension has been applied to 60 cases of diabetic branch retinal vein occlusion,diabetic macular edema and age-related macular degeneration patients through intravitreal injection. It was also been applied to 41 cases of diabetic retinopathy, epimacular membrane, proliferative vitreoretinopathy and idiopathic macular hole patients to assist pas plana vitrectomy (PPV). Whether TA particles can adhere to posterior hyaloid cortex, epiretinal membrane and internal limiting membrane during the surgery have been observed. During follow up, corrected visual acuity and intraocular pressure were recorded. Results: Five μm pore filter connected with three-way cock can remove the vehicle in TA suspension successfully and retain TA particles. When the new suspension was applied to assist PPV, it can adhere to posterior hyaloid cortex, epiretinal membrane, internal limiting membrane and visualized them clearly. In all the 41 cases that underwent PPV surgery, visual acuity of 30 cases increased or remained stable. Intraocular hypertension happened in 4 cases. Two cases of the 41 patients had cataract formation during follow up. In the 60 cases that underwent TA intravitreal injection, 45 cases increased their visual acuity at least 2 lines. Intraocular hypertension happened in 17 cases and 4 patients had cataract formation. None of the 101 patients caught endophthalmitis or other serious complications. Conclusion: Filter connected with three-way cock can remove the vehicle in TA suspension effectively and this procedure can be applied to intravitreal injection or PPV. This manipulation is so simple that it deserves to be popularized for clinical use.

关键词： Triamcinolone acetonide Safety Vitrectomy Intravitreal injection

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Neovascular Glaucoma in a Patient with X-linked Juvenile Retinoschisis

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Eye Science 2005年第3期21卷 140-141,151页

作者： chengguo Zuo changzheng chen Yiqiao Xing Lei Du The Department of Ophthalmology Renmin Hospital Wuhan University Wuhan 430060 China

Purpose: To report the rubeosis iridis and neovascular glaucoma findings in one patient of X-linked juvenile retinoschisis (XLRS).Methods: Color fundus photography, fluorescein angiography (FFA), OCT and B-scan were performed in a patient with X-linked juvenile retinoschisis complicated with neovascular ***: Color fundus photography, fluorescein angiography (FFA), OCT and B-scan unveiled a rare condition of XLRS complicated with neovascular ***: XLRS may complicate with neovascular glaucoma. It is necessary to test OCT, FFA, ERG and carefully examine the fundus of the follow eye when it comes to uncertain neovascular glaucoma of youth and child. And only in this way, can we exclude XLRS.

关键词：青光眼 X染色体遗传因素视网膜分层剥离青年

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Optical Design and Stray Light Analysis of the Space Infrared Optical System

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Journal of Harbin Institute of Technology(New Series) 2017年第1期24卷 32-36页

作者： Yuchen Zhao Yanjun Xu changzheng chen Fan Zhang Jianyue Ren Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China University of Chinese Academy of Sciences Beijing 100049China

This article describes a novel configuration design for a re-imaging off-axis catadioptric space infrared optical system,and in order to satisfy the signal noise ratio requirements of the system,the stray light of the system is necessary to analyze and restrain. The optical system with a focal length of 1 200 mm,an entrance pupil diameter of 600 mm,an F-number of 2,a field of view of 3°× 0. 15°,a working wave band of 8 μm-10 μm,and the image quality of the optical system almost approach to diffraction limits in all field of *** the mathematical models of stray light are built,and the suppressive structure is established to eliminate the effect of stray light. Finally,TraceP ro is used to analyze and simulate stray light with and without the suppressive structure,and also get the results of the PST curves. The results indicate that appropriate optical system and suppressive structure can highly reduce the stray light of the space infrared optical system.

关键词： space infrared optical system off-axis optical system stray light Point Source Transmission(PST)

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混合弹流润滑下内啮合直齿轮动态特性磨损退化研究

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振动与冲击 2021年第16期40卷 183-191页

作者：宁志远陈长征沈阳工业大学机械工程学院沈阳110870

针对现有磨损计算方法难以求解混合弹流润滑下内啮合齿轮磨损的问题,提出了黏着磨损与弹流润滑耦合的计算模型。根据弹流润滑理论计算油膜刚度,并将油膜刚度、齿面接触刚度以及承载系数结合构建了混合弹流润滑条件下的综合刚度模型以完... 详细信息

针对现有磨损计算方法难以求解混合弹流润滑下内啮合齿轮磨损的问题,提出了黏着磨损与弹流润滑耦合的计算模型。根据弹流润滑理论计算油膜刚度,并将油膜刚度、齿面接触刚度以及承载系数结合构建了混合弹流润滑条件下的综合刚度模型以完善动力学模型。为深入分析混合弹流润滑下动态啮合力与磨损量之间的关系,将累加的磨损量作为齿侧间隙代入到动力学模型中,最终得到不同啮合次数下的动态啮合力和磨损量。考虑动态啮合力与润滑的影响能够呈现静态干摩擦中所没有的啮合动态冲击特性。计算结果表明:进入段的磨损量大于退出段的磨损量;动态啮合力会随着磨损量的增加,在进入段增大,在退出段减小;在磨损初期动态啮合力会随着磨损量增加迅速收敛;油膜刚度对动态啮合力较为敏感,而不会受初期磨损的影响;综合刚度与承载系数在初期磨损时不会变化。

关键词：内啮合直齿轮黏着磨损混合弹流润滑承载系数油膜刚度动态啮合力

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On the technologies of Hα imaging spectrograph for the CHASE mission

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Science China(Physics,Mechanics & Astronomy) 2022年第8期65卷 29-36页

作者： Qiang Liu Hongjiang Tao changzheng chen chengshan Han Zhe chen Gui Mei Liang Yang Qinglong Hu Hongwei Xin Xiansheng Li Hongyu Guan Donglin Xue Mingchao Zhu Changhong Hu Qinghua Ha Yukun He cheng Fang Chuan Li Zhen Li Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China School of Astronomy and Space Science Nanjing UniversityNanjing 210023China Key Laboratory for Modern Astronomy and Astrophysics Ministry of EducationNanjing 210023China

The Hα imaging spectrograph(HIS) is the scientific payload of the first solar space mission, the Chinese Hα solar explorer(CHASE), supported by the China National Space Administration(CNSA). The CHASE/HIS achieves, for the first time in space, Hα spectroscopic observations with high spectral and temporal resolutions. Separate channels for the raster scanning mode(RSM) and continuum imaging mode(CIM) are integrated into one, and a highly integrated design is achieved through multiple folding of the optical path and ultra-light miniaturized components. The design of HIS implements a number of key technologies such as high-precision scanning of the optical field of view(FOV), high-precision integrated manufacturing inspection, a large-tolerance pre-filter window, and full-link solar radiation calibration. The HIS instrument has a pixel spectral resolution of 0.024 ? and can complete a full-Sun scanning within 46 s.

关键词： space-based telescope design and performance testing of optical systems scan imaging

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A Macular Hole in a Female Adult with Bilateral Coats Disease

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Eye Science 2003年第3期19卷 168-170页

作者： changzheng chen, Feng Wen, Libing Jiang, Lezheng Wu Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, China Zhongshan Ophthalmic Center Sun Yat-sen University Guangzhou 510060 China.

Purpose: To report a case of a macular hole in a female adult with bilateral Coats ***:The fundus photograph, fundus fluorescein angiography (FFA) and indocyanine green angiography (ICGA) were performed in two eyes, and observed theirs ***:Fundus photograph showed massive yellowish-white exudation in the temporal midperiphery of both eyes, but the degree was slighter in the right eye. There was 1/3 DD macular hole in left eye. FFA revealed general dilatation of capillaries, multiple aneurysms, and tortuous and closure of vessels in superotemporal midperiphery in both eyes, but the degree was slighter in the right eye. There was a one-third DD round transmitted fluorescence according the macula hole. ICGA revealed that hyperfluorescence of aneurysms in superotemporal midperiphery, the images of aneurysms were more clearly than in FFA. There was a 2/3 DD hypoflurescence of macula in the late phase of ***: FFA and ICGA have respective advantage in revealing vascular abnormalities of Coats disease. Maybe there was some relationship between the abnormalities of retinal vascular and hypoperfusion of choroidial vascular in macula in this case.

关键词：女性视网膜疾病黄斑裂洞荧光眼底血管造影术靛蓝花青血管造影术

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基于VMD和QPSO-SR的风电机组轴承故障提取方法

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太阳能学报 2019年第10期40卷 2946-2952页

作者：谷晓娇陈长征沈阳工业大学机械工程学院沈阳110870 辽宁省振动噪声控制技术工程研究中心沈阳110870

提出一种基于量子粒子群优化算法的自适应随机共振(quantum particle swarm optimization stochastic resonance,QPSO-SR)降噪和变分模态分解(variational mode decomposition,VMD)的风电机组轴承故障提取方法。首先根据原始故障振动信号特征采用量子粒子群优化算法自适应地进行随机共振参数优化;其次以信噪比最优的参数值对原始信号进行随机共振降噪处理,削弱噪声干扰和冲击成分对结果的影响并增强故障信号幅值;再用VMD法分解降噪处理后的信号,实现故障信号的提取。仿真分析和实验分析表明,该方法提高了VMD在噪声背景下的计算精度,实现风电机组滚动轴承故障的精确诊断。

关键词：滚动轴承风电机组故障诊断变分模态分解随机共振

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Scotopic Sensitivity of Central Retina in Early Age-Related Macular Degeneration

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Eye Science 2003年第1期19卷 15-19页

作者： changzheng chen, Lezheng Wu, Futian Jiang, Jiongji Liang, De-Zheng WuZhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, China Zhongshan Ophthalmic Center Sun Yat-sen University Guangzhou 510060 China.

Purpose: To test scotopic sensitivity and investigate whether there is rod systemdysfunction in the central retina in early age - related macular degeneration (AMD).Methods:Scotopic (450 nm stimulus) and photopic (white light stimulus) sensitivity in24 patients with early AMD was measured at 81 loci in central 25° of retina, andcompared with the age - match normal ***: Mean scotopic sensitivity of AMD patients was significantly lower than that ofthe normal controls. The patients of reduced scotopic sensitivity were more than those ofreduced photopic sensitivity. Scotopic sensitivity deficit decreased with increasingeccentricity with the greatest deficit was 2. 5°to 5.0°.Conclusions: Scotopic sensitivity was decreased in the early stage of AMD. Theparafoveal rod cells were selectively damaged in AMD. Scotopic sensitivity testing inmacula may be a useful tool to diagnose and measure the fundus dysfunction of AMD.

关键词：暗适应敏感性视网膜中央年龄相关性斑点恶化视功能损害

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含路面预瞄信息的车辆主动悬架有限频域多目标控制

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农业机械学报 2015年第12期46卷 294-300页

作者：王刚陈长征于慎波沈阳工业大学机械工程学院沈阳110870 辽宁省振动噪声控制技术工程研究中心沈阳110870

提出了一种考虑路面预瞄信息的有限频域线性变参数控制器设计方法,并将其应用于时变速度下的车辆悬架多目标控制。在控制器设计中,首先,利用Padé近似的方法处理一定距离内的路面预瞄信息,将车辆悬架系统增广为含速度信息的状态空间方... 详细信息

提出了一种考虑路面预瞄信息的有限频域线性变参数控制器设计方法,并将其应用于时变速度下的车辆悬架多目标控制。在控制器设计中,首先,利用Padé近似的方法处理一定距离内的路面预瞄信息,将车辆悬架系统增广为含速度信息的状态空间方程。其次,采用多胞形结构描述车辆前进速度的时变性。考虑到人体对4~8 Hz范围内的振动加速度较为敏感,且路面干扰仅发生在有限频段内,传统的全频域H∞控制方法并不能取得最优性能。以车身垂直加速度的有限频域H∞范数为优化性能指标,使其在路面干扰下的能量增益在关心频段内达到最小,同时考虑相关的时域约束条件。最后,通过数值实例验证了所提方法的有效性,对比于传统的全频域方法及无路面预瞄的控制方法,该方法能在时域约束条件得到满足的同时,有效地提高车辆的舒适性。

关键词：车辆主动悬架有限频域 H∞控制路面预瞄速度依赖控制器

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