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Effect of High-Order Aberrations and Satisfaction on Cataract Patients Implanted with Four Types of AcrySof Blue Light Filtering Intraocular Lens
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作者 Wei Wu Shengyou Yu Shengsheng Ma 《International Journal of Clinical Medicine》 2021年第8期307-315,共9页
<strong>Objective: </strong>The objective is to evaluate the visual acuity, high-order aberrations and satisfaction in the cataract patients with the implantation of different types of AcrySof blue light f... <strong>Objective: </strong>The objective is to evaluate the visual acuity, high-order aberrations and satisfaction in the cataract patients with the implantation of different types of AcrySof blue light filtering intraocular lens, which would provide the clinical guidance for the selection of individualized intraocular lens. <strong>Methods:</strong> From January 2019 to December 2020, the patients with age-related cataract in Guangzhou Red Cross Hospital were equally randomized to be divided into four groups. 20 patients (20 eyes) were implanted with AcrySof (SN60WF), which was the blue light filtering single focus group;20 patients (20 eyes) were implanted with blue light filtering aspheric multifocal intraocular lens (AcrySof ReSTOR IOL +3.0D, SN6AD1), which was the multifocal intraocular lens group;20 patients (20 eyes) were implanted with aspheric astigmatism correction intraocular lens (Toric SN6AT), which was the astigmatism group;20 patients (20 eyes) were implanted with blue filtering aspheric multifocal astigmatism correction intraocular lens (AcrySof ReSTOR IOL +2.5D IQ, SV25T0), which was the ART group. Three months after the operation, the patients were followed up with slit lamp to check the visual acuity, including uncorrected distance visual acuity (UCDVA), uncorrected near visual acuity (UCNVA), best corrected distance visual acuity, (BCDVA);the questionnaire surveys on the satisfaction of different intraocular lens implantation (far and near vision, glare, halo and abnormal visual symptoms);the iTrace visual function analyzer was used to check the total high-order aberrations (spherical aberration, wisdom aberration and Clover aberration) in the 3 mm pupil diameter. <strong>Results:</strong> Three months after cataract surgery, American Simplified version of questionnaire survey showed that the scores of near removing glasses in the multifocal group and the ART group were significantly better than those in the single focus group and the astigmatism group (<em>P</em> < 0.05);there was no significant difference in the satisfaction of far removing glasses, glare and halo in each group (<em>P</em> > 0.05). Three months after cataract surgery, there were statistically significant differences about UCDVA, BCDVA and UCNVA among the four groups (<em>F</em> = 18.189, <em>P </em>< 0.001), the UCNVA in the multifocal group and ART group was significantly better than that in the single focus group and the astigmatism group (<em>P</em> < 0.01). The difference of higher-order aberrations (total higher-order aberrations, wisdom aberrations, spherical aberrations, clover aberrations) was no statistically significant among the four groups (<em>P</em> > 0.05). <strong>Conclusion: </strong>Different types of AcrySof blue light filtering intraocular lens implantation could improve the far vision and satisfaction of cataract patients, without different higher-order aberrations. Multifocal intraocular lens and ART intraocular lens could significantly improve the far vision of patients and reduce the dependence on near glasses. 展开更多
关键词 CATARACT Intraocular Lens High-Order Aberrations Blue light filtering
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Protective Film for NiSO4.6H2O UV Light Filter Based on Diisocyanate-Bridged Polysilsesquioxane
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作者 Weimei Shi Hong Tian +2 位作者 Shengwei Hu Yao Xu Dong WU 《材料科学与工程(中英文版)》 2011年第1期1-11,共11页
关键词 甲苯二异氰酸酯 聚倍半硅氧烷 保护膜 滤波器 紫外线 桥联 光学晶体 透明薄膜
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Rendered image denoising method with filtering guided by lighting information 被引量:1
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作者 MA Minghui HU Xiaojuan +2 位作者 ZHANG Ripei CHEN Chunyi YU Haiyang 《Optoelectronics Letters》 2025年第4期242-248,共7页
The visual noise of each light intensity area is different when the image is drawn by Monte Carlo method.However,the existing denoising algorithms have limited denoising performance under complex lighting conditions a... The visual noise of each light intensity area is different when the image is drawn by Monte Carlo method.However,the existing denoising algorithms have limited denoising performance under complex lighting conditions and are easy to lose detailed information.So we propose a rendered image denoising method with filtering guided by lighting information.First,we design an image segmentation algorithm based on lighting information to segment the image into different illumination areas.Then,we establish the parameter prediction model guided by lighting information for filtering(PGLF)to predict the filtering parameters of different illumination areas.For different illumination areas,we use these filtering parameters to construct area filters,and the filters are guided by the lighting information to perform sub-area filtering.Finally,the filtering results are fused with auxiliary features to output denoised images for improving the overall denoising effect of the image.Under the physically based rendering tool(PBRT)scene and Tungsten dataset,the experimental results show that compared with other guided filtering denoising methods,our method improves the peak signal-to-noise ratio(PSNR)metrics by 4.2164 dB on average and the structural similarity index(SSIM)metrics by 7.8%on average.This shows that our method can better reduce the noise in complex lighting scenesand improvethe imagequality. 展开更多
关键词 establish paramet rendered image denoising Monte Carlo method filtering guided lighting information denoising algorithms image segmentation algorithm rendered image denoising method monte carlo methodhoweverthe
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A review of sources, pathways, and toxic effects of human exposure to benzophenone ultraviolet light filters 被引量:3
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作者 Ya-Nan Yao You Wang +3 位作者 Hengling Zhang Yanxia Gao Tao Zhang Kurunthachalam Kannan 《Eco-Environment & Health》 2024年第1期30-44,共15页
Benzophenone ultraviolet light filters(BPs)are high-production-volume chemicals extensively used in personal care products,leading to widespread human exposure.Given their estrogenic properties,the potential health ri... Benzophenone ultraviolet light filters(BPs)are high-production-volume chemicals extensively used in personal care products,leading to widespread human exposure.Given their estrogenic properties,the potential health risks associated with exposure to BPs have become a public health concern.This review aims to summarize sources and pathways of exposure to BPs and associated health risks.Dermal exposure,primarily through the use of sunscreens,constitutes a major pathway for BP exposure.At a recommended application rate,dermal exposure of BP-3 via the application of sunscreens may reach or exceed the suggested reference dose.Other exposure pathways to BPs,such as drinking water,seafood,and packaged foods,contribute minimal to the overall dose.Inhalation is a minor pathway of exposure;however,its contribution cannot be ignored.Human exposure to BPs is an order of magnitude higher in North America than in Asia and Europe.Studies conducted on laboratory animals and cells have consistently demonstrated the toxic effects of BP exposure.BPs are estrogenic and elicit reproductive and developmental toxicities.Furthermore,neurotoxicity,hepatotoxicity,nephrotoxicity,and carcinogenicity have been reported from chronic BP exposure.In addition to animal and cell studies,epidemiological investigations have identified associations between BPs and couples'fecundity and other reproductive disorders,as well as adverse birth outcomes.Further studies are urgently needed to understand the risks posed by BPs on human health. 展开更多
关键词 Benzophenone ultraviolet light filters Human exposure BP-3 Health effects Risk assessment
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Study on mode-filtered light sensor for methane detection 被引量:4
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作者 Suo Zhu Wu Shao Min Shuang +4 位作者 Yan Zhang Zhong Ping Li Martin M.E Choi Cai Hong Zhang Chuan Dong 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第2期210-212,共3页
A novel mode-filtered light gas sensor has been reported. It was constructed by inserting an optical fiber deposited by a thin silicone cladding of cryptophane A into a fused-silica capillary. When different concentra... A novel mode-filtered light gas sensor has been reported. It was constructed by inserting an optical fiber deposited by a thin silicone cladding of cryptophane A into a fused-silica capillary. When different concentration of methane gas was introduced to the sensor, the phenomenon that mode-filtered light intensity decreased with the increasing concentration of methane was observed. And a linear relationship was obtained within the methane concentration range of 0.0-16.0% (v/v). The detection limit was 0.06% (v/v). The mode-filtered light sensor has been exploited to respond to various concentrations of methane gas at room temperature. 展开更多
关键词 Mode-filtered light METHANE Cryptophane A
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A novel sensor of potassium ions based on mode-filtered light detection
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作者 Xiao Hong Zhao Li Ping Yang +3 位作者 Suo Zhu Wu Wen Ping Cheng Shao Min Shuang Chuan Dong 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第10期1243-1246,共4页
A novel potassium ions sensor based on mode-filtered light detection was reported. The analyzer was consisting of an optical fiber immobilized with a dye of bromocresol green and a fused-silica capillary. It was found... A novel potassium ions sensor based on mode-filtered light detection was reported. The analyzer was consisting of an optical fiber immobilized with a dye of bromocresol green and a fused-silica capillary. It was found that mode-filtered light intensity decreased with the concentration of potassium ions and a linear detection range of 0.25-20 mmol/L (R^2 = 0.9977) was obtained with a detection limit of 9 ×10^-5 mol/L as well as fast response, good reproducibility and reversibility in the working concentration range. 展开更多
关键词 Mode-filtered light Potassium ions Aqueous solution Bromocresol green
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基于TDLAS的氨痕量气体传感器设计
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作者 李延玲 游源 +2 位作者 钱枫 邓明星 崔蕊 《电子设计工程》 2026年第6期96-102,108,共8页
现有的氨痕量气体传感器在检测精度、灵敏度、工作稳定性和微型化方面仍有很大提升空间,文中应用TDLAS-WMS原理开发出一种氨痕量气体传感器。为提升传感器检测性能,设计了增量式PID算法实现激光器的恒温控制,以确保激光波长的精确调谐... 现有的氨痕量气体传感器在检测精度、灵敏度、工作稳定性和微型化方面仍有很大提升空间,文中应用TDLAS-WMS原理开发出一种氨痕量气体传感器。为提升传感器检测性能,设计了增量式PID算法实现激光器的恒温控制,以确保激光波长的精确调谐。此外,将鹈鹕优化算法(POA)和变分模态分解(VMD)进行融合用于数字滤波,与硬件滤波电路共同作用,以降低信号噪声。通过配置不同浓度的氨气进行谐波检测,并对得到的二次谐波进行光强归一化,以消除光强变化对检测精度的影响,最后采用分段拟合标定法进行浓度标定。实验结果表明,该传感器的检测灵敏度为3.73×10-3,测量最大误差仅为2.21%,可以满足氨痕量气体的实时监测需求。 展开更多
关键词 激光吸收光谱技术 激光器温度控制 数字滤波 光强归一化
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面向远距离空中小目标的可见光自动对焦改进算法研究
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作者 宫华伟 《科学技术创新》 2026年第4期41-44,共4页
本文提出了一种基于多尺度梯度特征与辅助信息融合的新型对焦评价函数,该函数结合了图像熵和频域高频能量,增强了对微弱特征的感知能力。在此基础上,本文构建了深度学习驱动的对焦预测框架。利用卷积神经网络(CNN)对小目标进行多尺度特... 本文提出了一种基于多尺度梯度特征与辅助信息融合的新型对焦评价函数,该函数结合了图像熵和频域高频能量,增强了对微弱特征的感知能力。在此基础上,本文构建了深度学习驱动的对焦预测框架。利用卷积神经网络(CNN)对小目标进行多尺度特征提取,并基于这些特征构建深度回归模型以实现离焦量的直接预测。为优化对焦搜索策略,将自动对焦过程建模为马尔可夫决策过程,引入强化学习以自适应学习高效策略,避免局部最优。此外,结合卡尔曼滤波对镜头位置进行状态估计与预测,实现了对高速运动小目标的预对焦和平滑跟踪。实验结果表明,与传统方法相比,本文提出的方法在对焦精度、对焦时间和鲁棒性方面均取得了显著提升。 展开更多
关键词 可见光相机 自动对焦 小目标 深度学习 KALMAN滤波
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基于智能传感器网络的公路隧道照明自适应控制系统构建
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作者 沈想爱 《移动信息》 2026年第1期37-39,共3页
针对传统公路隧道照明系统能耗高、响应滞后的问题,文中设计了基于智能传感器网络的自适应控制系统。选取BH1750光照传感器、RSU-600车流量传感器构建感知层,采用卡尔曼滤波融合多源数据,结合模糊PID算法实现亮度动态调节。通过200 m实... 针对传统公路隧道照明系统能耗高、响应滞后的问题,文中设计了基于智能传感器网络的自适应控制系统。选取BH1750光照传感器、RSU-600车流量传感器构建感知层,采用卡尔曼滤波融合多源数据,结合模糊PID算法实现亮度动态调节。通过200 m实际隧道试点实验表明,所提系统平均节能率达35.2%,亮度响应延迟≤0.8 s,照明均匀度≥0.75,平均无故障工作时间432 h,有效缓解了“黑洞/白洞效应”,能够兼顾行车安全与节能需求,具备工程应用价值。 展开更多
关键词 智能传感器网络 公路隧道照明 自适应控制 模糊PID 卡尔曼滤波
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An Improved Filter of Progressive TIN Densification for LiD AR Point Cloud Data 被引量:3
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作者 WANG Huan WANG Shugen +2 位作者 CHEN Qi JIN Weihua SUN Mingwei 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2015年第4期362-368,共7页
Based on the classic filter of progressive triangulated irregular network(TIN) densification, an improved filter is proposed in this paper. In this method, we divide ground points into grids with certain size and se... Based on the classic filter of progressive triangulated irregular network(TIN) densification, an improved filter is proposed in this paper. In this method, we divide ground points into grids with certain size and select the lowest points in the grids to reconstruct TIN in the process of iteration. Compared with the classic filter of progressive TIN densification(PTD), the improved method can filter out attached objects, avoid the interference of low objects and obtain relatively smooth bare-earth. In addition, this proposed filter can reduce memory requirements and be more efficient in processing huge data volume. The experimental results show that the filtering accuracy and efficiency of this method is higher than that of the PTD method. 展开更多
关键词 light detection and ranging(Li DAR) filtering progressive TIN densification(PTD) triangulated irregular network(TIN)
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Backscattering Light Model of Seawater for Modulated Lidar Based on the Stationarity of Light Field 被引量:1
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作者 冀航 马泳 +1 位作者 梁琨 王宏远 《Journal of Beijing Institute of Technology》 EI CAS 2007年第4期481-485,共5页
The backscattering signal, which arises from the pulsed laser traveling through water, has limited the lidar system sensitivity and underwater target contrast. The transmitted optical carrier is modulated to be ultras... The backscattering signal, which arises from the pulsed laser traveling through water, has limited the lidar system sensitivity and underwater target contrast. The transmitted optical carrier is modulated to be ultrashort pulsed laser and it is effective to suppress the backscattering to adopt the coherent detection technology by identifying the modulation envelope. A nonstationary light field is formed in seawater by the ultrashort pulsed laser. The inherent relationship between the nonstationary light field formed by modulated lidar and the stationary light field formed by conventional lidar was discussed and the backscattering light model of the stationary light field for the ultrashort pulsed laser was proposed. The backscattering signal in modulated lidar system was processed and analyzed in the frequency domain on the basis of the model. 展开更多
关键词 BACKSCATTERING stationary light field nonstationary light field frequency filtering modulated lidar
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基于机载LiDAR点云数据电力线交叉跨越测量方法
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作者 李邹军 黄文华 许志强 《北京测绘》 2026年第1期57-62,共6页
针对传统的电力线交叉跨越测量技术,传统人工+全站仪测量方式效率低、作业强度大的问题,实现新型智能化快速准确的交叉跨越测量,本文提出采用机载激光雷达(LiDAR)点云数据获取电力线路的高精度三维信息。对原始点云进行滤波和精细分类,... 针对传统的电力线交叉跨越测量技术,传统人工+全站仪测量方式效率低、作业强度大的问题,实现新型智能化快速准确的交叉跨越测量,本文提出采用机载激光雷达(LiDAR)点云数据获取电力线路的高精度三维信息。对原始点云进行滤波和精细分类,在非地面点中提取电力线点云,利用悬链线特性拟合得到电力线,通过指定电力线来获取其与地面的距离,实现高程测量,并与实测数据进行对比。结果表明,基于机载LiDAR点云数据能够实现高效率、高精度的电力线的提取和交叉跨越测量,可为实际工程的应用提供参考。 展开更多
关键词 机载激光雷达 电力线提取 点云滤波 悬链线
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基于2D激光雷达提高快速激光雷达惯性里程计定位精度的方法
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作者 赵威 严怀成 +1 位作者 高生 吕云凯 《上海航天(中英文)》 2026年第1期114-124,共11页
为解决传统快速激光雷达惯性里程计(FAST-LIO)在全球定位系统(GPS)拒止环境中,因初始高度默认全局坐标系原点、Z轴观测约束单一,导致无人机定位精度,尤其是高度方向精度退化,进而制约其整体定位性能进一步提升的问题,提出低成本2D激光... 为解决传统快速激光雷达惯性里程计(FAST-LIO)在全球定位系统(GPS)拒止环境中,因初始高度默认全局坐标系原点、Z轴观测约束单一,导致无人机定位精度,尤其是高度方向精度退化,进而制约其整体定位性能进一步提升的问题,提出低成本2D激光雷达与FAST-LIO集成的融合方案。方法上,先通过2D激光雷达完成极坐标转三维点云、随机采样一致性直线拟合、多重验证滤波及坐标转换,获取厘米级初始高度;然后将2D激光雷达与FAST-LIO自身的惯性测量单元、3D激光雷达结合,构建三重紧耦合系统;再将2D激光雷达观测融入迭代误差状态卡尔曼滤波(IESKF)观测矩阵,补充Z轴约束。该方法低成本易集成,有效提升无人机定位及位姿精度,支撑GPS拒止场景自主导航,未来将探索三维平面拟合优化适应性。 展开更多
关键词 同步定位与地图构建(SLAM) 雷达里程计 迭代误差状态卡尔曼滤波(IESKF) 紧耦合 四旋翼无人机
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VLC-Based Indoor Positioning Algorithm Combined with OFDM and Particle Filter 被引量:10
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作者 Jin Wang Haoxu Li +1 位作者 Xiaofeng Zhang Rangzhong Wu 《China Communications》 SCIE CSCD 2019年第1期86-96,共11页
Visible light communications(VLC) have recently attracted a growing interest and can be a potential solution to realize indoor positioning,however,the performance of existing indoor positioning system is limited by mu... Visible light communications(VLC) have recently attracted a growing interest and can be a potential solution to realize indoor positioning,however,the performance of existing indoor positioning system is limited by multipath distortion inside a room.In order to combat the effect of multipath distortion,this paper proposes an LED-based indoor positioning algorithm combined with hybrid OFDM(HOFDM),in which asymmetrically clipped optical OFDM(ACOOFDM) is transmitted on the odd subcarriers while using pulse amplitude modulated discrete multitone(PAM-DMT) to modulate the imaginary part of each even subcarrier.In this scheme,we take a combined approach where a received-signal-strength(RSS) technique is employed to determine the location of the receiver and realize the 3-D positioning by Trust-region-based positioning.Moreover,a particle filter is used to further improve the positioning accuracy.Results confirm that this proposed positioning algorithm can achieve high accuracy even with multipath distortion,and the algorithm has better performance when combined with particle filter. 展开更多
关键词 orthogonal frequency division multiplexing(OFDM) indoor positioning particle filter trust region VISIBLE light communications(VLC)
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新型照明电源谐波特性分析与抑制策略设计
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作者 马学超 梁庆 《光源与照明》 2026年第1期71-73,共3页
分析了LED照明电源的拓扑结构及其谐波产生机制,基于此建立了LED驱动电源的数学模型,利用快速傅里叶变换分析其谐波成分并进行验证。基于以上结果,提出了采用有源电力滤波器进行谐波抑制的策略。试验结果表明,该策略能有效降低谐波失真... 分析了LED照明电源的拓扑结构及其谐波产生机制,基于此建立了LED驱动电源的数学模型,利用快速傅里叶变换分析其谐波成分并进行验证。基于以上结果,提出了采用有源电力滤波器进行谐波抑制的策略。试验结果表明,该策略能有效降低谐波失真,提高系统的电能质量。 展开更多
关键词 新型照明电源 谐波特性 谐波分析 谐波抑制 有源电力滤波器 快速傅里叶变换
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Calibration and data restoration of light field modulated imaging spectrometer
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作者 Li-Juan Su Qiang-Qiang Yan +2 位作者 Yan Yuan Shi-Feng Wang Yu-Jian Liu 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第8期179-186,共8页
A light field modulated imaging spectrometer (LFMIS) can acquire the spatial-spectral datacube of targets of interest or a scene in a single shot. The spectral information of a point target is imaged on the pixels c... A light field modulated imaging spectrometer (LFMIS) can acquire the spatial-spectral datacube of targets of interest or a scene in a single shot. The spectral information of a point target is imaged on the pixels covered by a microlens. The pixels receive spectral information from different spectral filters to the diffraction and misalignments of the optical components. In this paper, we present a linear spectral multiplexing model of the acquired target spectrum. A calibration method is proposed for calibrating the center wavelengths and bandwidths of channels of an LFMIS system based on the liner-variable filter (LVF) and for determining the spectral multiplexing matrix. In order to improve the accuracy of the restored spectral data, we introduce a reconstruction algorithm based on the total least square (TLS) approach. Simulation and experimental results confirm the performance of the spectrum reconstruction algorithm and validate the feasibility of the proposed calibrating scheme. 展开更多
关键词 light field modulated imaging spectrometer linear-variable filter spectral calibration spectral re-construction
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基于多尺度加权引导滤波的弱光图像细节增强研究
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作者 翟书娟 索艳滨 李亚平 《激光杂志》 北大核心 2025年第4期140-145,共6页
图像传感器在捕捉弱光图像时往往会受到各种噪声的干扰,这些噪声不仅降低了弱光图像质量,还增加了弱光图像细节增强的难度。为此,提出了基于多尺度加权引导滤波的细节增强方法。对于弱光图像进行混合灰度变换以及多尺度加权引导滤波,实... 图像传感器在捕捉弱光图像时往往会受到各种噪声的干扰,这些噪声不仅降低了弱光图像质量,还增加了弱光图像细节增强的难度。为此,提出了基于多尺度加权引导滤波的细节增强方法。对于弱光图像进行混合灰度变换以及多尺度加权引导滤波,实现图像噪声去除。在弱光图像噪声去除的基础上,根据弱光图像的亮度分量、平均照射分量、反射分量进行全局非线性亮度校正,实现弱光图像细节增强。实验结果表明,所提方法对弱光图像的引导滤波效果较好,增强后的图像分辨率较高,色彩失真和灰度不均现象不显著,实际应用价值较高。 展开更多
关键词 多尺度加权引导滤波 弱光图像细节增强 像素点均值过滤 反射分量 全局非线性亮度校正
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轻型柴油机选择性催化还原颗粒捕集器怠速再生控制策略及其验证
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作者 马标 张方戈 +1 位作者 张波 滕勤 《车用发动机》 北大核心 2025年第4期74-78,86,共6页
为了满足国6b轻型车排放法规对氮氧化物和颗粒物排放的要求,开发了某轻型柴油机选择性催化还原颗粒捕集器(SDPF)。当车辆在交通拥挤、红绿灯较多的城市状况下运行时,SDPF再生效率低,导致SDPF堵塞甚至烧蚀,为了解决这一问题,构建车辆怠... 为了满足国6b轻型车排放法规对氮氧化物和颗粒物排放的要求,开发了某轻型柴油机选择性催化还原颗粒捕集器(SDPF)。当车辆在交通拥挤、红绿灯较多的城市状况下运行时,SDPF再生效率低,导致SDPF堵塞甚至烧蚀,为了解决这一问题,构建车辆怠速工况和怠速与城市工况之间转换的识别逻辑,基于压差流阻的碳载量模型计算碳载量作为再生触发条件,建立SDPF怠速再生控制策略。通过实车测试,在车辆减速至怠速、怠速、怠速转换至行车状态下,验证SDPF怠速再生控制策略。结果表明,SDPF再生效率显著提升,证明了SDPF怠速再生控制策略的有效性,提高了SDPF运行的安全性。 展开更多
关键词 轻型柴油机 选择性催化还原颗粒捕集器 再生 控制策略
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面向空间遮挡的复合代价光场快速三维成像方法
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作者 李安虎 龚祯昱 赵鑫 《数据采集与处理》 北大核心 2025年第2期365-373,共9页
光场相机凭借其多维多尺度的成像能力和极简的资源配置,显著拓展了空地海探索等非结构化环境中的成像应用边界。光场成像过程中容易受到遮挡和噪声影响而产生不可靠的深度估计,传统的深度细化方法计算成本高且效果差。提出了一种面向空... 光场相机凭借其多维多尺度的成像能力和极简的资源配置,显著拓展了空地海探索等非结构化环境中的成像应用边界。光场成像过程中容易受到遮挡和噪声影响而产生不可靠的深度估计,传统的深度细化方法计算成本高且效果差。提出了一种面向空间遮挡的复合代价光场快速三维成像方法,深入分析影响深度估计准确性的主要因素,针对不同空间遮挡模式,建立最优的光场快速滤波构架。使用像素点的单比特特征构造高度集成的复合代价,实现深度图像的细化和遮挡优化。实验表明,该方法的运算效率显著优于基于马尔可夫随机场等为代表的后期细化手段,且使三维成像的均方根误差提高51.3%,以较低的运算成本显著提高深度估计算法的可靠性,有望为光场成像技术在复杂场景应用提供有力支持。 展开更多
关键词 复杂环境 三维成像 光场相机 复合代价 快速滤波
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基于特征点检测的热态H型钢断面尺寸测量算法研究 被引量:1
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作者 郑宪广 刘元铭 +3 位作者 杜旺哲 陈康辉 王涛 王志华 《塑性工程学报》 北大核心 2025年第1期255-268,共14页
针对当前热态H型钢断面全尺寸测量需求,设计了一种基于线结构光的热态H型钢断面尺寸测量系统。测量系统由4个线结构光子系统、H型钢、电机等组成,通过各侧相机对H型钢进行图像采集,并将测量数据拼接实现热态H型钢断面全尺寸测量。为实... 针对当前热态H型钢断面全尺寸测量需求,设计了一种基于线结构光的热态H型钢断面尺寸测量系统。测量系统由4个线结构光子系统、H型钢、电机等组成,通过各侧相机对H型钢进行图像采集,并将测量数据拼接实现热态H型钢断面全尺寸测量。为实现热态H型钢断面轮廓信息的精确提取,提出一种基于法线的高斯滤波线结构光中心线提取方法,分析高斯滤波对线结构光截面灰度分布对称均匀程度的影响规律,利用几何矩构建高斯截面灰度分布模型;在构建的模型基础上,设计一种基于法线的线结构光中心线提取方法,根据初提取中心线法线方向进行中心坐标计算和插值优化,实现热态H型钢线结构光图像中心线快速高精度提取。设计一种基于特征点检测的热态H型钢断面尺寸测量算法,分析热态H型钢轮廓形状特点和数学特征,拾取尺寸特征点,实现热态H型钢断面全尺寸测量。结果表明,与考虑膨胀系数后的热态H型钢尺寸相比,高度、宽度和翼缘的最大相对误差分别为0.06%、1.8%和1.76%;腹板厚度最大绝对误差为0.23 mm。提出的测量算法满足测量需求,能够实现热态H型钢断面尺寸测量。 展开更多
关键词 H型钢 线结构光测量 高斯滤波 几何矩 线结构光中心线提取
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