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A Line Complex-Based Evolutionary Algorithm for Many-Objective Optimization 被引量:6
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作者 Liang Zhang Qi Kang +2 位作者 Qi Deng Luyuan Xu Qidi Wu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第5期1150-1167,共18页
In solving many-objective optimization problems(MaO Ps),existing nondominated sorting-based multi-objective evolutionary algorithms suffer from the fast loss of selection pressure.Most candidate solutions become nondo... In solving many-objective optimization problems(MaO Ps),existing nondominated sorting-based multi-objective evolutionary algorithms suffer from the fast loss of selection pressure.Most candidate solutions become nondominated during the evolutionary process,thus leading to the failure of producing offspring toward Pareto-optimal front with diversity.Can we find a more effective way to select nondominated solutions and resolve this issue?To answer this critical question,this work proposes to evolve solutions through line complex rather than solution points in Euclidean space.First,Plücker coordinates are used to project solution points to line complex composed of position vectors and momentum ones.Besides position vectors of the solution points,momentum vectors are used to extend the comparability of nondominated solutions and enhance selection pressure.Then,a new distance function designed for high-dimensional space is proposed to replace Euclidean distance as a more effective distancebased estimator.Based on them,a novel many-objective evolutionary algorithm(MaOEA)is proposed by integrating a line complex-based environmental selection strategy into the NSGAⅢframework.The proposed algorithm is compared with the state of the art on widely used benchmark problems with up to 15 objectives.Experimental results demonstrate its superior competitiveness in solving MaOPs. 展开更多
关键词 Environmental selection line complex many-objective optimization problems(MaOPs) Plücker coordinate
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A Preliminary Study of Mapping Genes Underlying Complex Traits Based on Chromosome Segment Substitution Lines 被引量:2
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作者 Z.X. Tang  C.W. Xu 《分子植物育种》 CAS CSCD 2007年第2期242-244,共3页
Complex traits are the features whose properties are determined by multiple factors, which can be genetic or environmental. Most of economically important characteristics of plants and animals belong to this special ... Complex traits are the features whose properties are determined by multiple factors, which can be genetic or environmental. Most of economically important characteristics of plants and animals belong to this special catego- 展开更多
关键词 染色体 复合体 基因表达 植物研究
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A Characterization of Complex Projective Spaces by Sections of Line Bundles
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作者 Shuyu Liang Yanan Gao Yicai Zhao 《Advances in Pure Mathematics》 2015年第8期450-453,共4页
Let M be a n-dimensional compact irreducible complex space with a line bundle L. It is shown that if M is completely intersected with respect to L and dimH0(M, L) = n + 1, then M is biholomorphic to a complex projecti... Let M be a n-dimensional compact irreducible complex space with a line bundle L. It is shown that if M is completely intersected with respect to L and dimH0(M, L) = n + 1, then M is biholomorphic to a complex projective space Pn of dimension n. 展开更多
关键词 complex SPACE PROJECTIVE SPACE line BUNDLE COMPLETE Intersected
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3D reconstruction of complex curved objects from line drawings
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作者 Sun Yanling Dong Lijun 《Computer Aided Drafting,Design and Manufacturing》 2016年第2期13-17,共5页
An active research topic in computer vision and graphics is developing algorithms that can reconstruct the 3D surface of curved objects from line drawings. There are a number of algorithms have been dedicated to solve... An active research topic in computer vision and graphics is developing algorithms that can reconstruct the 3D surface of curved objects from line drawings. There are a number of algorithms have been dedicated to solve this problem, but they can't solve this problem when the geometric structure of a curved object becomes complex. This paper proposes a novel approach to reconstructing a complex curved 3D object from single 2D line drawings. Our approach has three steps: (1) decomposing a complex line drawing into several simpler line drawings and transforming them into polyhedron; (2) reconstructing the 3D wireframe of curved object from these simpler line drawings and generating the curved faces; (3) combining the 3D objects into the complete objects. A number of examples are given to demonstrate the ability of our approach to successfully perform reconstruction of curved objects which are more complex than previous methods. 展开更多
关键词 3D reconstruction line drawings complex curved objects
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Measuring the complexity of product line architecture with vADL
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作者 ZHANG Tao CAO Yan-ping +1 位作者 ZHANG Chang-li MA Chun-yan 《通讯和计算机(中英文版)》 2008年第9期19-22,共4页
关键词 线架构 SPL 软件 计算机技术
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基于无人机红外图像的绝缘子污渍故障检测
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作者 原宗辉 谭磊 +2 位作者 赵留学 齐伟强 杜觉晓 《红外技术》 北大核心 2026年第2期234-240,共7页
针对无人机红外采集到的绝缘子污渍图像纹理复杂度较高的问题,提出输电线路绝缘子污渍故障检测方法,精准有效检测绝缘子污渍故障,降低其发生闪络或击穿等故障风险,保证电网的平稳供电。通过Laplace(拉普拉斯)算子提取初始绝缘子红外图... 针对无人机红外采集到的绝缘子污渍图像纹理复杂度较高的问题,提出输电线路绝缘子污渍故障检测方法,精准有效检测绝缘子污渍故障,降低其发生闪络或击穿等故障风险,保证电网的平稳供电。通过Laplace(拉普拉斯)算子提取初始绝缘子红外图像边缘,结合USRNet网络增强所提取的此类图像边缘轮廓特征,降低此类图像内的复杂背景纹理干扰,获得高清晰度低纹理复杂度的超分辨率重建绝缘子红外图像;向Faster RCNN检测模型中输入此类超分辨率图像,实现输电线路绝缘子污渍故障的检测。结果显示,该方法的绝缘子无人机红外图像边缘提取效果较好,所获得的超分辨率重建图像清晰度高,图像内的复杂背景纹理干扰被有效去除掉,整体图像质量得到显著优化;可实现绝缘子污渍故障的精准有效检测,检测性能稳定,平均检测速度理想,具有较高的实际应用性。 展开更多
关键词 无人机 红外图像 纹理复杂度 输电线路 绝缘子 污渍故障
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一种用于空间要素几何特征度量的新型等效矩形EAPR指数集
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作者 肖天英 齐修东 葛小三 《测绘工程》 2026年第1期19-26,共8页
几何特征指数是量化图形几何特征的基本方法,其准确性和完整性直接影响空间数据处理的效率和成果质量。然而,现有的几何特征指数在实际应用中存在无法全面满足需求的问题。为此,文中提出一种与原始图形具有相同面积和周长的新型等效矩形... 几何特征指数是量化图形几何特征的基本方法,其准确性和完整性直接影响空间数据处理的效率和成果质量。然而,现有的几何特征指数在实际应用中存在无法全面满足需求的问题。为此,文中提出一种与原始图形具有相同面积和周长的新型等效矩形,基于此等效矩形构建几何特征指数集。实验结果表明,平均宽度是影响建筑物功能分类的重要特征;对于宽度均匀度的图形,可以利用等效矩形平均长度近似计算骨架线长度;通过与现有形状特征指数的相关性分析,验证了文中提出的3种矩形指数对图形形状刻画的有效性和独立性;结合理论分析和实际例证,文中提出的矩形指数在刻画图形复杂度方面相较于现有方法具有明显优势,有效提升空间要素几何特征的量化精度,为空间数据处理提供了新的工具和方法。 展开更多
关键词 等面积等周长矩形 平均宽度 骨架线长度 形状复杂度 建筑物形状特征
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高速铁路复杂地形条件下选线设计研究
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作者 李岳汶 《全面腐蚀控制》 2026年第1期226-229,共4页
复杂地形具有地质条件复杂,地形起伏剧烈,环境敏感性强等特征,对传统高速铁路选线方法提出严峻挑战。通过系统研究复杂地形下选线设计的基本理论,深入分析山区,丘陵等典型地形的选线关键技术,建立多目标优化决策模型。研究表明,基于地... 复杂地形具有地质条件复杂,地形起伏剧烈,环境敏感性强等特征,对传统高速铁路选线方法提出严峻挑战。通过系统研究复杂地形下选线设计的基本理论,深入分析山区,丘陵等典型地形的选线关键技术,建立多目标优化决策模型。研究表明,基于地形适应性原则的选线理论,结合先进勘察技术和智能优化算法,能够有效解决复杂地形选线难题,以贵南高铁为例验证方法的实用性,为类似工程提供重要参考。 展开更多
关键词 高速铁路 复杂地形 选线设计 多目标优化 智能算法
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低频辐射环境下多导线电磁耦合计算新方法
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作者 叶志红 翟宇凡 《微波学报》 北大核心 2026年第1期60-67,共8页
鉴于低频辐射持续时间很长而多导体传输线结构精细,场线耦合时域计算效率极低,同时缺乏高效的场线耦合频域模型与算法。本文将频域有限差分法(FDFD)与传输线方程和矩量法(MoM)相结合,研究了一种新型的场线耦合频域算法,实现屏蔽腔体环... 鉴于低频辐射持续时间很长而多导体传输线结构精细,场线耦合时域计算效率极低,同时缺乏高效的场线耦合频域模型与算法。本文将频域有限差分法(FDFD)与传输线方程和矩量法(MoM)相结合,研究了一种新型的场线耦合频域算法,实现屏蔽腔体环境下多导体传输线低频辐射干扰的准确快速计算。首先,采用传输线方程构建多导体传输线的低频辐射耦合模型,通过FDFD方法进行求解,推导建立新型的FDFD-TL矩阵方程。然后,使用MoM准确快速计算多导体传输线沿线的切向电场,获取FDFD-TL矩阵方程的等效电压源项。最后,结合复共轭梯度法与MPI并行技术,快速求解FDFD-TL矩阵方程,获得多导体传输线沿线及端接负载电流响应。通过相应计算实例的数值模拟,与MoM全波仿真结果从精度和计算耗时两方面进行对比,充分验证了该方法的计算精度与效率。 展开更多
关键词 低频辐射 多导体传输线耦合 矩量法 FDFD-TL矩阵方程 MPI并行的复共轭梯度法
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双地铁车站间复杂内支撑体系下的深大基坑设计
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作者 吴鑫鑫 《工程建设与设计》 2026年第3期55-58,共4页
以某市地铁某换乘区间深基坑工程为依托,基于当地地质水文条件,优化内支撑体系,提出复杂内支撑设计方案,并通过结合数值模拟及现场监测进行验证。结果表明,该体系可将围护结构最大水平位移控制在23.6 mm,邻近地铁隧道沉降量小于8 mm,满... 以某市地铁某换乘区间深基坑工程为依托,基于当地地质水文条件,优化内支撑体系,提出复杂内支撑设计方案,并通过结合数值模拟及现场监测进行验证。结果表明,该体系可将围护结构最大水平位移控制在23.6 mm,邻近地铁隧道沉降量小于8 mm,满足规范及地铁保护要求;数值模拟与现场监测数据均在合理误差以内,验证了设计的科学性与合理性。 展开更多
关键词 深大基坑 双地铁区间 复杂内支撑体系 软土地区
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A SCREW DISLOCATION IN A THREE-PHASE COMPOSITE CYLINDER MODEL WITH INTERFACIAL RIGID LINES 被引量:2
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作者 Fang Qihong Liu Youwen Jiang Chiping 《Acta Mechanica Solida Sinica》 SCIE EI 2005年第4期283-294,共12页
The problem of the elastic interaction between a screw dislocation and a three-phase circular inclusion with interracial rigid lines (anti-cracks) is investigated. An efficient and concise method for the complex mul... The problem of the elastic interaction between a screw dislocation and a three-phase circular inclusion with interracial rigid lines (anti-cracks) is investigated. An efficient and concise method for the complex multiply connected region is developed, with which explicit series form solutions of the complex potentials in the matrix, and the interphase layer and inclusion regions are derived. Based on the complex potentials, the image force on the screw dislocation is then calculated by using the Peach-Koehler formula. The equilibrium position of the dislocation is discussed in detail for various rigid line geometries, interphase layer thicknesses and material property combinations. The main results show that the interracial rigid lines exert a significant perturbation effect on the motion of the screw dislocation near the circular inclusion surrounded by an interphase layer. 展开更多
关键词 screw dislocation interfacial rigid lines interphase layer complex potential method image force
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Simulation of incompressible multiphase flows with complex geometry using etching multiblock method 被引量:1
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作者 Haoran LIU Kai MU Hang DING 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2016年第11期1405-1418,共14页
The incompressible two-phase flows are simulated using combination of an etching multiblock method and a diffuse interface (DI) model, particularly in the com- plex domain that can be decomposed into multiple rectan... The incompressible two-phase flows are simulated using combination of an etching multiblock method and a diffuse interface (DI) model, particularly in the com- plex domain that can be decomposed into multiple rectangular subdomains. The etching multiblock method allows natural communications between the connected subdomains and the efficient parallel computation. The DI model can consider two-phase flows with a large density ratio, and simulate the flows with the moving contact line (MCL) when a geometric formulation of the MCL model is included. Therefore, combination of the etch- ing method and the DI model has potential to deal with a variety of two-phase flows in industrial applications. The performance is examined through a series of numerical exper- iments. The convergence of the etching method is firstly tested by simulating single-phase flows past a square cylinder, and the method for the multiphase flow simulation is vali- dated by investing drops dripping from a pore. The numerical results are compared with either those from other researchers or experimental data. Good agreement is achieved. The method is also used to investigate the impact of a droplet on a grooved substrate and droplet generation in flow focusing devices. 展开更多
关键词 etching multiblock method complex geometry multiphase flow movingcontact line (MCL) MULTIBLOCK
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Modifying factor for determining broadband complex permeability of magnetic thin films
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作者 杜刚 江建军 +5 位作者 袁林 别少伟 马强 田斌 张秀成 何华辉 《中国有色金属学会会刊:英文版》 CSCD 2007年第A02期886-888,共3页
A new method of the modifying factor for determining the broadband complex permeability of magnetic thin films,was proposed. Based on the measurement technology of shot-end microstrip line and the new modify factor,a ... A new method of the modifying factor for determining the broadband complex permeability of magnetic thin films,was proposed. Based on the measurement technology of shot-end microstrip line and the new modify factor,a series of FeCo-based magnetic thin films deposited on the oxidized silicon substrates and with an in-plane uniaxial anisotropy were measured in the frequency range of 0.5-5 GHz. The results fit well with the Landau-Lifchitz-Gilbert theory in a broad frequency range. 展开更多
关键词 磁性薄膜 微波测量法 复合物渗透性 微波传输线
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基于复杂网络的城市轨道交通网络韧性分析 被引量:1
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作者 杨向飞 童冬冬 张静芳 《中国铁路》 北大核心 2025年第11期141-150,共10页
为分析城市轨道交通网络应对不同攻击时的韧性特征,基于复杂网络和韧性理论,构建定量网络结构韧性评估模型。模型包括初始、攻击和恢复3个阶段,采用点度值、聚类系数、中心性以及随机排序4种不同的攻击和恢复模式,以网络密度、网络效率... 为分析城市轨道交通网络应对不同攻击时的韧性特征,基于复杂网络和韧性理论,构建定量网络结构韧性评估模型。模型包括初始、攻击和恢复3个阶段,采用点度值、聚类系数、中心性以及随机排序4种不同的攻击和恢复模式,以网络密度、网络效率及网络连通率3个特征作为衡量城市轨道交通网络韧性的关键指标,通过空间向量计算网络结构韧性值。以北京市城市轨道交通为例,运用Space-L和Space-C模型构建线路网络与换乘网络,分析4种攻击和恢复模式下网络韧性指标变化情况。研究表明,线路网络规模大于换乘网络规模,但其网络密度和效率均极低。同时,2种网络在经受DA模式攻击下,网络各项指标下降最快;在ZR模式下,网络各项指标恢复最快;在ZADR模式下2个网络同时具有最高韧性水平,韧性值分别为0.21244和0.52209。建议北京市轨道交通应重点加强站点、线路之间的衔接性,对中心性和点度值较高的站点和线路进行保护,以提高整体网络的韧性水平。 展开更多
关键词 城市交通 复杂网络 韧性评估 线路网络 换乘网络
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ANTIPLANE PROBLEM OF CIRCULAR ARC INTERFACIAL RIGID LINE INCLUSIONS 被引量:2
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作者 刘又文 方棋洪 王明斌 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2004年第4期458-466,共9页
The antiplane problem of circular arc rigid line inclusions under antiplane concentrated force and longitudinal shear loading was dealt with. By using Riemann-Schwarz's symmetry principle integrated with the singu... The antiplane problem of circular arc rigid line inclusions under antiplane concentrated force and longitudinal shear loading was dealt with. By using Riemann-Schwarz's symmetry principle integrated with the singularity analysis of complex functions, the general solution of the problem and the closed form solutions for some important practical problems were presented. The stress distribution in the immediate vicinity of circular arc rigid line end was examined in detail. The results show that the singular stress fields near the rigid inclusion tip possess a square-root singularity similar to that for the corresponding crack problem under antiplane shear loading, but no oscillatory character. Furthermore, the stresses are found to depend on geometrical dimension, loading conditions and materials parameters. Some practical results concluded are in agreement with the previous solutions. 展开更多
关键词 rigid line inclusion circular arc interface antiplane problem complex variable method
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PLANE ELASTIC PROBLEM ON RIGID LINES ALONG CIRCULAR INCLUSION
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作者 刘又文 方棋洪 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2005年第12期1585-1594,共10页
The plane elastic problem of circular-arc rigid line inclusions is considered. The model is subjected to remote general loads and concentrated force which is applied at an arbitrary point inside either the matrix or t... The plane elastic problem of circular-arc rigid line inclusions is considered. The model is subjected to remote general loads and concentrated force which is applied at an arbitrary point inside either the matrix or the circular inclusion. Based on complex variable method, the general solutions of the problem were derived. The closed form expressions of the sectionally holomorphic complex potentials and the stress fields were derived for the case of the interface with a single rigid line. The exact expressions of the singular stress fields at the rigid line tips were calculated which show that they possess a pronounced oscillatory character similar to that for the corresponding crack problem under plane loads. The influence of the rigid line geometry, loading conditions and material mismatch on the stress singularity coefficients is evaluated and discussed for the case of remote uniform load. 展开更多
关键词 complex variable method circular inclusion interfacial rigid line concentrated force
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师范认证理念下的“复变函数”双线教学改革与实践——基于课程目标达成度的视角
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作者 邱克娥 熊胜兰 +1 位作者 任善静 刘葵 《贵州开放大学学报》 2025年第2期66-72,共7页
基于师范专业认证理念,文章以复变函数课程教学为实践载体,通过重塑课程目标、重构教学内容和方式、优化课程考核评价方式,深入开展双线教学实践研究。研究结果显示,在师范认证理念引领下实施的“复变函数”双线教学改革,不仅使教学有... 基于师范专业认证理念,文章以复变函数课程教学为实践载体,通过重塑课程目标、重构教学内容和方式、优化课程考核评价方式,深入开展双线教学实践研究。研究结果显示,在师范认证理念引领下实施的“复变函数”双线教学改革,不仅使教学有的放矢,推动课程目标达成度的实质性提升,同时也促进了教学团队的持续发展,最终推动了育人质效的稳步提升。 展开更多
关键词 师范认证 复变函数 双线教学 课程目标达成度
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寒区隧道衬砌构件水-热-力耦合加载模型试验设计
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作者 孙克国 贾敬龙 +2 位作者 封坤 许炜萍 章慧健 《实验技术与管理》 北大核心 2025年第12期10-18,共9页
寒区隧道衬砌结构受到水分场、温度场和应力场之间的复杂耦合作用,易引发冻胀开裂等严重病害,直接威胁结构安全与耐久性。现有研究多聚焦于衬砌混凝土材料性能的演化规律,对多场耦合条件下衬砌结构整体响应与破坏机理的研究尚有不足。... 寒区隧道衬砌结构受到水分场、温度场和应力场之间的复杂耦合作用,易引发冻胀开裂等严重病害,直接威胁结构安全与耐久性。现有研究多聚焦于衬砌混凝土材料性能的演化规律,对多场耦合条件下衬砌结构整体响应与破坏机理的研究尚有不足。为完善寒区隧道衬砌耦合作用研究方法,深入揭示寒区隧道衬砌水-热-力耦合机制,该文基于“以直代曲”+“单边围堰”+“受荷冻融”的思路,研发了一种寒区隧道衬砌构件的水-热-力耦合加载试验方法,通过结合相应的数值仿真模型,揭示了寒区隧道衬砌水-热演化规律及承载-变形动态响应机制,探明了寒区衬砌结构的破坏模式与裂纹扩展路径。该研究可为寒区隧道衬砌结构的抗防冻设计与服役性能预测提供理论与技术支撑。 展开更多
关键词 隧道衬砌 水-热-力耦合 复杂冻融 室内试验 数值仿真
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SDH-DETR轻量化绝缘子缺陷检测算法
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作者 周景 刘心 +1 位作者 唐振洋 董晖 《电子测量技术》 北大核心 2025年第11期88-104,共17页
为解决无人机在输电线路绝缘子巡检中目标检测算法面临的模型复杂度高、小目标缺陷检测精度不足和上下采样过程中容易造成特征丢失等挑战,本文提出了一种基于轻量化改进的RT-DETR绝缘子缺陷检测算法(SDH-DETR)。首先,以RT-DETR作为基线... 为解决无人机在输电线路绝缘子巡检中目标检测算法面临的模型复杂度高、小目标缺陷检测精度不足和上下采样过程中容易造成特征丢失等挑战,本文提出了一种基于轻量化改进的RT-DETR绝缘子缺陷检测算法(SDH-DETR)。首先,以RT-DETR作为基线算法,降低优化难度并提高鲁棒性;其次,采用轻量级StarNet作为主干网络,在显著降低模型复杂度的同时提升特征提取能力;接着,引入DySample动态上采样模块,通过基于采样点的自适应上采样方法,有效减少细节丢失与图像失真;最后,利用Harr小波变换下采样模块(HWD),实现低频与高频信息的高效融合,抑制复杂背景干扰并增强对小目标的检测能力。在复杂背景数据集上的验证实验表明,SDH-DETR的平均精度达98.5%,较基线算法提升0.9%,参数量和计算量分别减少43%和46.1%,检测速度达78.6 fps。这表明该算法在保证高准确性的同时,实现了轻量化设计,满足了输电线路巡检对效率和性能的实际需求。 展开更多
关键词 输电线路 目标检测 绝缘子缺陷检测 复杂背景 轻量化 RT-DETR算法
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基于谐波幅值比变化的复杂线路故障选线方法
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作者 陈兴 吕干云 +3 位作者 李思萱 庄洁薇 叶加星 毕睿华 《电气自动化》 2025年第2期50-53,共4页
在小电流接地系统中,发生单相接地故障可能导致电流通过接地路径流回地面,引发一系列潜在危害。针对这一问题,结合电能质量监测系统的数据,提出了一种基于谐波幅值比突变量的单相接地故障诊断方法,并将该突变量作为判据用于故障选线。... 在小电流接地系统中,发生单相接地故障可能导致电流通过接地路径流回地面,引发一系列潜在危害。针对这一问题,结合电能质量监测系统的数据,提出了一种基于谐波幅值比突变量的单相接地故障诊断方法,并将该突变量作为判据用于故障选线。通过对电能质量监测的谐波数据进行采集,分析故障发生前后一个周期的谐波电流幅值比的突变量,判断是否发生接地故障,并进一步确定故障线路。利用MATLAB软件建立了装设消弧线圈的复杂线路的单相接地故障模型,仿真结果验证了所提方法的有效性及新判据的可靠性。所提方法无需借助额外设备,能够直观而准确地诊断故障,从而显著提高了选线的可靠性。 展开更多
关键词 小电流接地 复杂线路 单相接地故障 谐波幅值比突变量 故障选线
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