期刊文献+
共找到2,064篇文章
< 1 2 104 >
每页显示 20 50 100
一种改进型Canny的焊缝缺陷快速检测方法
1
作者 穆向阳 王宣 《激光杂志》 北大核心 2026年第2期70-76,共7页
针对Canny算法在焊缝缺陷检测中出现边缘信息丢失、检测精度不足以及实时性偏低等问题,提出一种基于FPGA的改进型Canny焊缝缺陷检测方法。首先,该方法将自适应中值滤波和双边滤波技术结合起来,有效抑制噪声的同时最大限度地将焊缝边缘... 针对Canny算法在焊缝缺陷检测中出现边缘信息丢失、检测精度不足以及实时性偏低等问题,提出一种基于FPGA的改进型Canny焊缝缺陷检测方法。首先,该方法将自适应中值滤波和双边滤波技术结合起来,有效抑制噪声的同时最大限度地将焊缝边缘细节保留下来;其次,为了提升边缘提取的完整性,利用高斯加权的Sobel算子计算图像梯度;最后,通过引入基于梯度的自适应多级阈值选择策略,有效连接焊缝边缘的同时提升检测的自适应性。本研究采用FPGA的高速并行处理技术与分层流水线架构,开发了一种在硬件加速平台下的实时边缘检测系统。实验结果表明,该方法在焊缝区域内的边缘连通性较“自适应中值滤波+Canny算法”提升了24%,边缘强度提升了22.7%,并在100 MHz时钟频率下处理一张640×480的图片仅耗时4.1005 ms。本算法在检测精度及实时性方面更具优势,满足复杂环境下对焊缝缺陷检测的相关需求。 展开更多
关键词 canny算子 FPGA 自适应中值-双边滤波 自适应多级阈值 并行架构
原文传递
基于改进Canny算法的转辙机缺口检测系统研究
2
作者 李水明 陶汉卿 《机电工程技术》 2026年第2期105-109,共5页
针对铁路转辙机缺口人工检测工作量大且测量精度容易受人为因素影响的问题,提出一种基于改进Canny算法的转辙机缺口时间检测系统。系统硬件由工控机、视觉相机和背景光源组成;软件采用基于改进型的Canny边缘检测算法结合海康威视Vi⁃sion... 针对铁路转辙机缺口人工检测工作量大且测量精度容易受人为因素影响的问题,提出一种基于改进Canny算法的转辙机缺口时间检测系统。系统硬件由工控机、视觉相机和背景光源组成;软件采用基于改进型的Canny边缘检测算法结合海康威视Vi⁃sionMaster软件算法平台开发。软件设计采用自适应中值滤波去除噪声干扰,通过像素梯度值和非极大值提取图像边缘特征,使用最大类间方法来自适应选取转辙机缺口图像的高、低阈值,利用VisionMaster算法平台进行图像标定,对缺口图像边缘轮廓进行线线间测量,并通过标定转换为转辙机缺口的实际物理尺寸。实验测试表明,转辙机缺口检测系统采用改进Canny算法能够有效对转辙机缺口图像边缘轮廓进行识别,实现了对缺口大小的实时测量。 展开更多
关键词 转辙机 canny算法 缺口检测
在线阅读 下载PDF
基于Canny轮廓提取与区域分割的堆锦数字制版方法
3
作者 于峻璎 夏乾龙 +1 位作者 姜中华 闫向军 《服装学报》 北大核心 2026年第1期28-35,共8页
针对传统堆锦制作中拆版速率低的问题,提出一种基于图像处理的堆锦智能制版算法。以传统堆锦图像为研究对象,采用双边滤波进行去噪与色彩均衡处理,以增强图案细节;利用Canny算法进行轮廓提取与优化,形成合理的连通区域;通过Two-Pass算... 针对传统堆锦制作中拆版速率低的问题,提出一种基于图像处理的堆锦智能制版算法。以传统堆锦图像为研究对象,采用双边滤波进行去噪与色彩均衡处理,以增强图案细节;利用Canny算法进行轮廓提取与优化,形成合理的连通区域;通过Two-Pass算法进行连通区域标记,并利用K-means聚类上色,生成以色彩坐标为特征的数字化拆版结果。研究表明:该方法能够高效、准确地识别与分割堆锦底稿,显著提升拆版效率。该实验为堆锦技艺的数字化传承与样本保存提供了新的技术路径。 展开更多
关键词 堆锦 智能拆版 canny边缘检测 数字化 图像处理
在线阅读 下载PDF
Influence of negative information dissemination and vaccination behavioral decision-making on epidemic spreading in a three-layer network
4
作者 Liang'an Huo Leyao Yin 《Chinese Physics B》 2025年第6期667-681,共15页
Information plays a crucial role in guiding behavioral decisions during public health emergencies. Individuals communicate to acquire relevant knowledge about an epidemic, which influences their decisions to adopt pro... Information plays a crucial role in guiding behavioral decisions during public health emergencies. Individuals communicate to acquire relevant knowledge about an epidemic, which influences their decisions to adopt protective measures.However, whether to disseminate specific information is also a behavioral decision. In light of this understanding, we develop a coupled information–vaccination–epidemic model to depict these co-evolutionary dynamics in a three-layer network. Negative information dissemination and vaccination are treated as separate decision-making processes. We then examine the combined effects of herd and risk motives on information dissemination and vaccination decisions through the lens of game theory. The microscopic Markov chain approach(MMCA) is used to describe the dynamic process and to derive the epidemic threshold. Simulation results indicate that increasing the cost of negative information dissemination and providing timely clarification can effectively control the epidemic. Furthermore, a phenomenon of diminishing marginal utility is observed as the cost of dissemination increases, suggesting that authorities do not need to overinvest in suppressing negative information. Conversely, reducing the cost of vaccination and increasing vaccine efficacy emerge as more effective strategies for outbreak control. In addition, we find that the scale of the epidemic is greater when the herd motive dominates behavioral decision-making. In conclusion, this study provides a new perspective for understanding the complexity of epidemic spreading by starting with the construction of different behavioral decisions. 展开更多
关键词 negative information VACCINATION epidemic spreading behavioral decision-making three-layer network
原文传递
A surrogate model for estimating rock stress by a hollow inclusion strain cell in a three-layer medium
5
作者 Changkun Qin Wusheng Zhao +2 位作者 Weizhong Chen Peiyao Xie Shuai Zhou 《International Journal of Mining Science and Technology》 2025年第3期363-381,共19页
Accurate acquisition of the rock stress is crucial for various rock engineering applications.The hollow inclusion (HI) technique is widely used for measuring in-situ rock stress.This technique calculates the stress te... Accurate acquisition of the rock stress is crucial for various rock engineering applications.The hollow inclusion (HI) technique is widely used for measuring in-situ rock stress.This technique calculates the stress tensor by measuring strain using an HI strain cell.However,existing analytical solutions for stress calculation based on an HI strain cell in a double-layer medium are not applicable when an HI strain cell is used in a three-layer medium,leading to erroneous stress calculations.To address this issue,this paper presents a method for calculating stress tensors in a three-layer medium using numerical simulations,specifically by obtaining a constitutive matrix that relates strain measurements to stress tensors in a three-layer medium.Furthermore,using Latin hypercube sampling (LHS) and orthogonal experimental design strategies,764 groups of numerical models encompassing various stress measurement scenarios have been established and calculated using FLAC^(3D)software.Finally,a surrogate model based on artificial neural network (ANN) was developed to predict constitutive matrices,achieving a goodness of fit (R^(2)) of 0.999 and a mean squared error (MSE) of 1.254.A software program has been developed from this surrogate model for ease of use in practical engineering applications.The method’s accuracy was verified through numerical simulations,analytical solution and laboratory experiment,demonstrating its effectiveness in calculating stress in a three-layer medium.The surrogate model was applied to calculate mining-induced stress in the roadway roof rock of a coal mine,a typical case for stress measurement in a three-layer medium.Errors in stress calculations arising from the use of existing analytical solutions were corrected.The study also highlights the significant errors associated with using double-layer analytical solutions in a three-layer medium,which could lead to inappropriate engineering design. 展开更多
关键词 Stress measurement Over-coring stress relief method three-layer medium Surrogate model Numerical simulation
在线阅读 下载PDF
Thermal and solutal Marangoni convection in three-layered viscous flows:Insights for liquid metal battery optimization
6
作者 SHAHEEN Sidra HUANG Hu-lin +2 位作者 ARAIN Muhammad Bilal BHATTI Muhammad Mubashir KHALIQUE Chaudry Masood 《Journal of Central South University》 2025年第6期2087-2100,共14页
This study examines the intricate occurrences of thermal and solutal Marangoni convection in three-layered flows of viscous fluids,with a particular emphasis on their relevance to renewable energy systems.This researc... This study examines the intricate occurrences of thermal and solutal Marangoni convection in three-layered flows of viscous fluids,with a particular emphasis on their relevance to renewable energy systems.This research examines the flow of a three-layered viscous fluid,considering the combined influence of heat and solutal buoyancy driven Rayleigh-Bénard convection,as well as thermal and solutal Marangoni convection.The homotopy perturbation method is used to examine and simulate complex fluid flow and transport phenomena,providing important understanding of the fundamental physics and assisting in the optimization of various battery configurations.The inquiry examines the primary elements that influence Marangoni convection and its impact on battery performance,providing insights on possible enhancements in energy storage devices.The findings indicate that the velocity profiles shown graphically exhibit a prominent core zone characterized by the maximum speed,which progressively decreases as it approaches the walls of the channel.This study enhances our comprehension of fluid dynamics and the transmission of heat and mass in intricate systems,which has substantial ramifications for the advancement of sustainable energy solutions. 展开更多
关键词 viscous fluid three-layered closed geometries electrical conductivity thermal convection solutal convection mass diffusivity homotopy perturbation methods
在线阅读 下载PDF
Constructing a three-layered passivation structure of NiO_(x)/poly(V-pTPD)/PFN-Br toward buried interface for inverted perovskite solar cells
7
作者 Xinru Qin Chengyu Tan +13 位作者 Chunjie Huang Hongkun Wei Yuqi Cui Xiangjin Du Rui Zhang Shiyu Jiang Zhenghao Liu Yiming Li Huijue Wu Jiangjian Shi Yanhong Luo Dongmei Li Xianggao Li Qingbo Meng 《Journal of Energy Chemistry》 2025年第12期9-17,I0002,共10页
Buried interface passivation is crucial for high-efficiency,stable perovskite solar cells(PSCs).Herein,we design a three-layer passivation structure toward the buried interface of inverted PSCs,consisting of NiO_(x),p... Buried interface passivation is crucial for high-efficiency,stable perovskite solar cells(PSCs).Herein,we design a three-layer passivation structure toward the buried interface of inverted PSCs,consisting of NiO_(x),poly(V-p-TPD)and PFN-Br(V-p-TPD,N,N'-di-p-tolyl-N,-N'-bis(4-vinylphenyl)-[1,1'-biphenyl]-4,4'-diamine;PFN-Br,poly[(9,9-bis(3'-((N,N-dimethyl)-N-ethylammonium)-propyl)-2,7-fluorene)-alt-2,7-(9,9-dioctylfluorene)]dibromide).Typically,in situ poly(V-p-TPD)layer on the NiO_(x) surface was obtained by a simple thermal crosslinking process.This poly(V-p-TPD)/NiO_(x) bilayer structure is beneficial for hole extraction and high-quality perovskite films with larger grain sizes and less lattice distortion.On this basis,the PFN-Br is further introduced as a surface modification layer,which can not only optimize the energy level alignment with the perovskite but also passivate defects and suppress carrier recombination at the perovskite bottom interface.Finally,inverted PSCs based on(FA_(0.95)Cs_(0.05))PbI_(3) present 25.5%efficiency with a low V_(OC)deficit.Besides,the devices could maintain 91.15%of the initial efficiency after being stored at 85℃for 1080 h,indicating excellent thermal stability.This work highlights the potential of a three-layered passivation structure based on crosslinking polymer HTLs for highly efficient and stable PSCs. 展开更多
关键词 Inverted perovskite solar cells Buried interface three-layer passivation structure In situ thermal polymerization Crosslinked polymer Thermal stability
在线阅读 下载PDF
Direct-chill semi-continuous casting process of three-layer composite ingot of 4045/3004/4045 aluminum alloys 被引量:6
8
作者 蒋会学 张海涛 +1 位作者 秦克 崔建忠 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第8期1692-1697,共6页
Three-layer composite ingot of 4045/3004/4045 aluminum alloys was prepared by direct-chill semi-continuous casting process,the temperature field distribution near the composite interface,macro-morphology,microstructur... Three-layer composite ingot of 4045/3004/4045 aluminum alloys was prepared by direct-chill semi-continuous casting process,the temperature field distribution near the composite interface,macro-morphology,microstructure and composition distribution of the composite interface were investigated.The results show that semi-solid layer with a certain thickness forms near the interface due to the effect of cooling plate,which ensures successful implementation of casting the composite ingot.Two different aluminum alloys are well bonded metallurgically.The mechanical properties of composite interface were measured,the tensile and shearing strengths of composite interface are 105 and 88 MPa,respectively,which proves that the composite interface is a kind of metallurgical bonding. 展开更多
关键词 aluminum alloys three-layer composite ingot direct-chill semi-continuous casting composite interface structures properties
在线阅读 下载PDF
Improving electrochemical performances of LiFePO_4 /C cathode material via a novel three-layer electrode 被引量:1
9
作者 肖政伟 胡国荣 +1 位作者 杜柯 彭忠东 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第11期3324-3329,共6页
As an improvement on the conventional two-layer electrode (active material layerlcurrent collector), a novel sandwich-like three-layer electrode (conductive layerlactive material layertcurrent collector) for catho... As an improvement on the conventional two-layer electrode (active material layerlcurrent collector), a novel sandwich-like three-layer electrode (conductive layerlactive material layertcurrent collector) for cathode material LiFePO4/C was introduced in order to improve its electrochemical performance. LiFePO4/C in the three-layer electrode exhibited superior rate capability in comparison with that in the two-layer electrode in accordance with charge-discharge examination. Cyclic voltammetry and electrochemical impedance spectroscopy indicated that Fe3+/Fe2+ redox couple for LiFePO4 in the three-layer electrode displayed faster kinetics, better reversibility and much lower charge transfer resistance than that in the two-layer electrode in electrochemical process. For three-layer electrode, the holes in the surface of active material layer were filled by smaller acetylene black grains, which formed electrical connections and provided more pathways to electron transport to/from LiFePO4/C particles exposed to the bulk electrolyte. 展开更多
关键词 lithium ion cells LIFEPO4 cathode electrode configuration three-layer electrode electrochemical performances
在线阅读 下载PDF
一种新的基于Canny算子数字图像边缘检测算法 被引量:2
10
作者 关雪梅 田国刚 《安阳师范学院学报》 2025年第2期11-16,共6页
提出并研究了一种基于Canny算子的改进数字图像边缘检测算法,在Canny算子基础上,引入了自适应高斯滤波及多尺度边缘响应融合策略,以提高边缘检测的鲁棒性和精度。不同噪声水平下的图像实验验证结果表明,改进后的算法在边缘定位精度、抗... 提出并研究了一种基于Canny算子的改进数字图像边缘检测算法,在Canny算子基础上,引入了自适应高斯滤波及多尺度边缘响应融合策略,以提高边缘检测的鲁棒性和精度。不同噪声水平下的图像实验验证结果表明,改进后的算法在边缘定位精度、抗噪性能以及计算效率方面均优于传统Canny算子,能够更加准确地提取图像中的重要边缘信息。研究为数字图像处理中的边缘检测问题提供了新思路。 展开更多
关键词 图像处理 canny算子 边缘检测
在线阅读 下载PDF
基于高低阈值Canny算子的遥感影像特征边缘检测 被引量:2
11
作者 曾菲 《电子设计工程》 2025年第10期167-170,175,共5页
遥感影像中地物边缘具有不同的对比度和强度,增加了边缘检测的难度。为有效检测影像特征边缘,提出基于高低阈值Canny算子的遥感影像特征边缘检测方法。在对遥感影像进行去噪与增强处理后,依据像素点的梯度方向,将非极大值的像素点梯度... 遥感影像中地物边缘具有不同的对比度和强度,增加了边缘检测的难度。为有效检测影像特征边缘,提出基于高低阈值Canny算子的遥感影像特征边缘检测方法。在对遥感影像进行去噪与增强处理后,依据像素点的梯度方向,将非极大值的像素点梯度幅值设置为零,将大于高阈值的像素点作为强特征点,将介于高低阈值之间的像素点作为弱特征点,将小于低阈值的像素点作为非边缘点。通过遍历全部的边缘特征点,将分裂点周边的弱特征点转化为强特征点,删除孤立边缘特征点,再连接所有强特征点,完成对特征边缘的检测。实验显示,该方法的特征边缘检测结果与实际特征边缘基本一致,边缘特征点检测完整度可达到97%,说明该方法能够完整、精准地检测影像特征边缘。 展开更多
关键词 遥感影像 特征边缘检测 高低阈值canny算子 边缘特征提取 边缘细化
在线阅读 下载PDF
基于改进Canny算法的航天电子装联焊点缺陷检测方法 被引量:1
12
作者 杨志 赵亚飞 +2 位作者 王薇 杨瑞栋 吴彦威 《计算机测量与控制》 2025年第9期261-270,共10页
航天电子装联中焊点的质量对设备的可靠性至关重要,焊接缺陷的检测是确保系统稳定运行的关键;为提升航天电子装联过程中焊接缺陷检测的效率和准确性,研究提出了一种基于改进Canny算法的图像处理方法;研究采用双边滤波技术在平滑噪声的... 航天电子装联中焊点的质量对设备的可靠性至关重要,焊接缺陷的检测是确保系统稳定运行的关键;为提升航天电子装联过程中焊接缺陷检测的效率和准确性,研究提出了一种基于改进Canny算法的图像处理方法;研究采用双边滤波技术在平滑噪声的同时保留边缘信息,结合Otsu阈值分割算法来自动确定最佳阈值;通过设置双阈值来确定强边缘和弱边缘,引入Hough变换填补断裂的边缘;实验结果表明,基于改进Canny的系统在各类焊点检测中表现出色,在0.12 mm网板中,正常焊点和桥接焊点的检测准确率分别为98.89%和98.21%;在0.18 mm网板中,该系统在少焊和过焊焊点的检测准确率分别为97.56%和98.47%;同时,验证了改进Canny算法在准确率、漏检率和运行时间方面的差异均具有统计学意义;此外,改进Canny系统在计算时间和CPU使用率上优于其他两种算法,表现出该系统在实际应用中的优越性。 展开更多
关键词 机器视觉 边缘检测 canny 图像预处理 航天电子装联
在线阅读 下载PDF
基于改进Canny 算子的岩石裂隙识别算法
13
作者 杨东辉 苏经纬 乔伟 《地下空间与工程学报》 北大核心 2025年第S2期581-588,共8页
边缘检测是岩石裂隙图像识别领域的一个重要方向。针对经典Canny算法在边缘检测精度方面的不足,提出一种基于改进Canny算子的岩石裂隙识别算法,采用双边滤波代替原始高斯滤波对图像进行平滑去噪;采用4方向的3×3 Sobel算子代替原始2... 边缘检测是岩石裂隙图像识别领域的一个重要方向。针对经典Canny算法在边缘检测精度方面的不足,提出一种基于改进Canny算子的岩石裂隙识别算法,采用双边滤波代替原始高斯滤波对图像进行平滑去噪;采用4方向的3×3 Sobel算子代替原始2×2模板计算图像梯度;采用Otsu算法自适应确认Canny高低阈值。选取单一型、偏Y型与T型岩石裂隙图像进行仿真实验,从边缘像素统计与算法执行效率两个方面对其进行评价。结果表明:与经典Canny算法、Sobel算子相比,改进Canny算法C/A值分别降低80.9%~90.3%、54.4%~76.7%,C/B值分别降低67.3%~82.6%、43.7%~76.0%;改进Canny算法边缘点连接程度好,伪边缘抑制性强,在边缘检测精度与整体功能性方面均取得了较大进步,但执行效率有待进一步提高。改进Canny算法为岩石裂隙识别方面的研究提供了新思路。 展开更多
关键词 边缘检测 岩石裂隙识别 改进canny算子 OTSU算法 双边滤波
原文传递
基于Canny-Hough的灌溉渠道边界快速检测算法研究
14
作者 陆红飞 毛涵宇 +3 位作者 周豪 甄博 仲瑶 杨泊 《灌溉排水学报》 2025年第5期47-56,共10页
【目的】构建一种灌溉渠道边界快速检测算法。【方法】针对灌溉渠道边界的识别与检测问题,采用无人机采集句容东山河和盐城伍佑港的渠道影像,结合Canny边缘检测和Hough变换技术提取渠道边界线,提出了一种基于参照直线和垂直距离的边界... 【目的】构建一种灌溉渠道边界快速检测算法。【方法】针对灌溉渠道边界的识别与检测问题,采用无人机采集句容东山河和盐城伍佑港的渠道影像,结合Canny边缘检测和Hough变换技术提取渠道边界线,提出了一种基于参照直线和垂直距离的边界归类方法,并分别采用线性拟合和二次多项式拟合方法,评估了边界线的拟合精度。【结果】相比原始图片,采用800×400尺寸图片进行边界提取效果最好,检测时间低于1.3 s,且基本能够描绘渠道边界走势;二次多项式拟合效果优于线性拟合,句容河右侧边界拟合时,二次多项式拟合和线性拟合决定系数(R^(2))分别为0.9592、0.9492;尤其是在处理因障碍物而形成的边界噪点时,能够更准确地描绘边界走势。此外,基于参照直线和垂直距离的边界归类方法,能够高效准确地获取渠道边界,二次曲线拟合时R^(2)均超过0.99。【结论】在传统Canny检测和Hough变换基础上,基于参照直线和垂直距离的分组方法能够实现多条边界快速检测,本研究进一步推动了机器视觉算法在灌溉工程管理中的应用。 展开更多
关键词 canny HOUGH 灌溉渠道 边界检测 无人机
在线阅读 下载PDF
基于改进Canny的水稻倒伏区域提取方法
15
作者 柴俊 王浩陈 《现代信息科技》 2025年第2期12-15,共4页
为衡量农作物受灾后倒伏带来的产量与经济损失,利用改进的图像边缘检测技术来获取倒伏区域面积。在现有Canny算子边缘检测的基础上,采用中值滤波替代高斯函数来平滑处理图像。再采用自适应双阈值和广义链区分真伪边缘点、消除伪边缘点,... 为衡量农作物受灾后倒伏带来的产量与经济损失,利用改进的图像边缘检测技术来获取倒伏区域面积。在现有Canny算子边缘检测的基础上,采用中值滤波替代高斯函数来平滑处理图像。再采用自适应双阈值和广义链区分真伪边缘点、消除伪边缘点,最后通过线性拟合和霍夫变换获得边缘直线。由于倒伏区域和正常区域存在明显的分界现象和倒伏纹理增多的特征可准确提取倒伏区域。试验结果表明,五个实验地块倒伏面积提取误差只有9.2%,9.4%,8.9%,7.9%和8.7%。 展开更多
关键词 倒伏作物 图像识别 边缘检测 改进canny
在线阅读 下载PDF
考虑灰度转换和Canny边缘检测算子的胎儿头围自动测量研究
16
作者 沈超 彭琢创 《国外电子测量技术》 2025年第6期168-173,共6页
胎儿头围的准确测量对于产前评估和生长发育监测具有重要意义,然而传统方法在处理超声图像时常受到边界模糊和组织复杂度高的干扰。提出一种融合图像预处理与改进分割模型的自动测量方法,通过灰度转换强化图像对比度,结合Canny边缘检测... 胎儿头围的准确测量对于产前评估和生长发育监测具有重要意义,然而传统方法在处理超声图像时常受到边界模糊和组织复杂度高的干扰。提出一种融合图像预处理与改进分割模型的自动测量方法,通过灰度转换强化图像对比度,结合Canny边缘检测算子提取清晰边界,提升目标区域显著性。在此基础上构建引入注意力机制的编码解码式网络结构,利用多尺度特征融合与跳跃连接优化分割精度,并在跳跃路径中嵌入注意力模块,增强对目标区域的关注能力。实验采用真实临床数据集进行评估,与传统模型和基础分割网络相比,该模型在准确率、重叠指标和边界表达上表现更优,准确率达到0.956,IoU值为0.865,平均测量误差率下降至9.6%,轮廓闭合度提高至0.89。消融测试结果显示,预处理与注意力机制的组合对性能提升具有协同作用。结果表明,该模型在保持效率的同时,显著提升了测量精度与边界连续性,具备良好的临床应用潜力。 展开更多
关键词 灰度转换 canny边缘检测算子 自动测量 注意力机制
原文传递
改进Canny算子在零件尺寸测量中的应用 被引量:3
17
作者 张晓阳 何军红 +1 位作者 牛云 张御 《机械科学与技术》 北大核心 2025年第4期625-631,共7页
零件尺寸视觉测量目前多采用像素级的边缘检测算法,不能满足高精度的测量需求。为提高零件尺寸测量精度,提出一种基于改进Canny算子的亚像素级零件尺寸测量方法。首先采用自适应中值-高斯滤波对零件图像进行滤波处理,在保留较多边缘信... 零件尺寸视觉测量目前多采用像素级的边缘检测算法,不能满足高精度的测量需求。为提高零件尺寸测量精度,提出一种基于改进Canny算子的亚像素级零件尺寸测量方法。首先采用自适应中值-高斯滤波对零件图像进行滤波处理,在保留较多边缘信息的同时有效去除噪声;然后对图像进行梯度计算并通过二次插值寻找边缘点;其次通过编写的链接算法对边缘点进行链接并进行双阈值处理,提取到图像亚像素边缘轮廓;最后获取轮廓的最小外接矩形并得到零件尺寸。实验表明,该方法有效解决了零件轮廓的精确定位问题,测量误差在1个像素尺寸以内,在保证测量精度和测量效率的同时具有较高的稳定性。 展开更多
关键词 视觉测量 canny 亚像素边缘检测 二次插值 最小外接矩形
在线阅读 下载PDF
Deformation and heat treatment ability of three-layer 6009/7050/6009 Al alloy clad slab prepared by direct-chill casting 被引量:4
18
作者 Guang-yuan YAN Feng MAO +2 位作者 Zhi-qiang CAO Ting-ju LI Tong-min WANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第1期9-19,共11页
Three-layer6009/7050/6009aluminum alloy clad slab was fabricated by an innovative direct-chill casting process.To study the response of the clad slab to plastic deformation and heat treatments,homogenization annealing... Three-layer6009/7050/6009aluminum alloy clad slab was fabricated by an innovative direct-chill casting process.To study the response of the clad slab to plastic deformation and heat treatments,homogenization annealing,hot rolling,solution and aging were successively performed on the as-cast6009/7050/6009clad samples.The results revealed that excellent metallurgical bonding between7050alloy layer and6009alloy layer was achieved under optimal parameters.The clad ratio obviously decreased when the annealed sample was rolled to55%hot reduction level,and then changed slightly with further rolling.Furthermore,the content of rodlike Zn-rich phases increased significantly in7050alloy layer in the homogenized clad samples after rolling at55%,65%and75%hot reduction levels,and the higher level of hot reduction resulted in narrower diffusion layer.Subsequent solution and aging significantly improved the hardness in7050alloy layer,interfaces and6009alloy layers of the rolled samples except for the thin side for the75%hot reduction sample. 展开更多
关键词 aluminum alloy three-layer clad slab direct-chill casting plastic deformation heat treatment
在线阅读 下载PDF
Wave Scattering by a Submerged Sphere in Three-Layer Fluid 被引量:1
19
作者 Minakshi Ghosh Manomita Sahu Dilip Das 《Journal of Marine Science and Application》 CSCD 2022年第1期37-50,共14页
Using linear water wave theory,three-dimensional problems concerning the interaction of waves with spherical structures in a fluid which contains a three-layer fluid consisting of a layer of finite depth bounded above... Using linear water wave theory,three-dimensional problems concerning the interaction of waves with spherical structures in a fluid which contains a three-layer fluid consisting of a layer of finite depth bounded above by freshwater of finite depth with free surface and below by an infinite layer of water of greater density are considered.In such a situation timeharmonic waves with a given frequency can propagate with three wavenumbers.The sphere is submerged in either of the three layers.Each problem is reduced to an infinite system of linear equations by employing the method of multipoles and the system of equations is solved numerically by standard technique.The hydrodynamic forces(vertical and horizontal forces)are obtained and depicted graphically against the wavenumber.When the density ratio of the upper and middle layer is made to approximately one,curves for vertical and horizontal forces almost coincide with the corresponding curves for the case of a two-layer fluid with a free surface.This means that in the limit,the density ratio of the upper and middle layer goes to approximately one,the solution agrees with the solution for the case of a two-layer fluid with a free surface. 展开更多
关键词 three-layer fluid Wave scattering Submerged sphere Hydrodynamic forces Vertical and horizontal forces Linear water wave theory Density-stratified three-layer fluid Submerged spherical structure Underwater sphere
在线阅读 下载PDF
One-step hydrothermal synthesis of 2,5-PDCA-containing MgAl-LDHs three-layer composite coating with high corrosion resistance on AZ31 被引量:1
20
作者 Fan Shi Jingmao Zhao +3 位作者 Mohammad Tabish Jingbao Wang Pu Liu Jiayu Chang 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第7期2541-2557,共17页
The addition of 2,5-pyridinedicarboxylic acid(2,5-PDCA)to the Mg-Al LDH coating,which was prepared by one-step hydrothermal synthesis,had extremely enhanced the corrosion protection of AZ31 Mg alloy,although the 2,5-P... The addition of 2,5-pyridinedicarboxylic acid(2,5-PDCA)to the Mg-Al LDH coating,which was prepared by one-step hydrothermal synthesis,had extremely enhanced the corrosion protection of AZ31 Mg alloy,although the 2,5-PDCA could not be intercalated into the interlayer spacing.The corrosion current density of 0.05 mol L^(−1)2,5-PDCA LDH containing LDH coating is 3.18 nA cm^(−2),reduced by two orders of magnitude compared to the LDH coating without inhibitor,and the corrosion inhibition efficiency of the coating is 98.05%.The coating formed on the surface of AZ31 was peeled off from the substrate by using a mechanical method and SEM observation of the cross-section showed that the coating consisted of three different layers.The innermost layer is a thick layer that consists of Mg(OH)_(2)and the intermediate layer is LDH,which is vertical to the substrate and the outmost layer is a thin but very dense deposit layer of LDH agglomerates with complexes of 2,5-PDCA and Mg.This kind of sediment/LDH/Mg(OH)_(2)three-layer composite structure was accountable for the increase in the corrosion resistance of AZ31 Mg alloy. 展开更多
关键词 three-layer composite coating Hydrothermal synthesis 2 5-PDCA MgAl-LDHs PEELING
在线阅读 下载PDF
上一页 1 2 104 下一页 到第
使用帮助 返回顶部