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雄商高铁黄河特大桥长联钢桁梁柔性拱设计

铁道标准设计 2025年第1期69卷 67-73页

作者：刘凯孙宗磊王江波张上中国铁路设计集团有限公司天津300308 中国铁路经济规划研究院有限公司北京100038

为适应黄河河槽宽度大、地震烈度高和无砟轨道高速行车等要求,经过桥型方案比选,雄商高铁跨越黄河采用长联多孔连续钢桁梁柔性拱,孔跨布置为(60+80+4×260+280+80+60)m,联长为1602.7 m。黄河桥主桥桁高15 m,桁宽13.8 m,采用带竖杆的三... 详细信息

为适应黄河河槽宽度大、地震烈度高和无砟轨道高速行车等要求,经过桥型方案比选,雄商高铁跨越黄河采用长联多孔连续钢桁梁柔性拱,孔跨布置为(60+80+4×260+280+80+60)m,联长为1602.7 m。黄河桥主桥桁高15 m,桁宽13.8 m,采用带竖杆的三角形桁架,拱高50 m,柔性吊杆,桥面采用正交异性钢桥面板,上面铺设15 cm厚混凝土板,方便无砟轨道铺设;下部采用双柱钢筋混凝土实体桥墩,桩基础采用ϕ2.0 m摩擦桩,桩基采用桩底注浆技术有效减小桩长;最后结合桥位处具体情况,采用钢桁梁悬拼、钢拱竖转的施工方案。研究结果表明:该长联钢桁梁柔性拱结构具有良好刚度,梁端转角控制为0.778‰rad,竖向刚度为1/2107;各杆件、吊杆、锚箱和拱脚等受力复杂部位均满足规范要求;悬拼、竖转施工方案能够二次利用扣塔,同时开设多个工作面,可大幅节省工期,经济性好。该桥的设计、建设将为我国铁路长联无砟轨道钢桥的建造和发展提供借鉴和参考。

关键词：高速铁路铁路桥黄河特大桥长联钢桁梁柔性拱无砟轨道悬臂拼装法钢拱竖转

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基于跨尺度特征提取的锻件表面裂纹检测算法

计算机集成制造系统 2025年第02期31卷 499-511页

作者：张岳张上王恒涛张朝阳许欢熊偌炎三峡大学水电工程智能视觉监测湖北省重点实验室三峡大学湖北省建筑质量检测装备工程技术研究中心三峡大学计算机与信息学院三峡大学经济与管理学院三峡大学电气与新能源学院

锻件表面裂纹危害性大，检测效率低，为解决传统人工磁粉检测锻件裂纹场景中存在的问题，提出一种锻件表面裂纹实时检测算法。首先采集重卡转向节生产流水线中探伤车间的磁粉检测图像，制作锻件表面裂纹数据集；然后提出轻量多尺度卷积... 详细信息

锻件表面裂纹危害性大，检测效率低，为解决传统人工磁粉检测锻件裂纹场景中存在的问题，提出一种锻件表面裂纹实时检测算法。首先采集重卡转向节生产流水线中探伤车间的磁粉检测图像，制作锻件表面裂纹数据集；然后提出轻量多尺度卷积模块LMSConv,实现单模块跨尺度特征提取，同时提出大型可分离内核注意力快速空间金字塔池化模块LSKA-SPPF,进一步加强整体跨尺度特征融合能力；最后，更改Bbox损失函数为Focal EIoU,以提高锚框回归精度。锻件表面裂纹数据集与NEU-DET数据集上的实验结果表明算法检测精度高，复杂度低，对比其他主流单阶段目标检测算法，所提算法漏检率和误检率降低，具有较强的鲁棒性，能够满足锻件裂纹检测的需要。

关键词：表面缺陷检测跨尺度特征锻件裂纹单阶段目标检测

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A family of symmetric mixed finite elements for linear elasticity on tetrahedral grids

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Science China Mathematics 2015年第2期58卷 297-307页

作者： HU Jun zhang shang You LMAM and School of Mathematical Sciences Peking University Department of Mathematical Sciences University of Delaware

A family of stable mixed finite elements for the linear elasticity on tetrahedral grids are constructed,where the stress is approximated by symmetric H(div)-Pk polynomial tensors and the displacement is approximated by C-1-Pk-1polynomial vectors,for all k *** main ingredients for the analysis are a new basis of the space of symmetric matrices,an intrinsic H(div)bubble function space on each element,and a new technique for establishing the discrete inf-sup *** particular,they enable us to prove that the divergence space of the H(div)bubble function space is identical to the orthogonal complement space of the rigid motion space with respect to the vector-valued Pk-1polynomial space on each *** optimal error estimate is proved,verified by numerical examples.

关键词： mixed finite element symmetric finite element linear elasticity conforming finite element tetrahedral grid inf-sup condition

面向复合型水利人才培养的“生态水力学”课程建设研究

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教育教学论坛 2025年第3期 57-60页

作者：唐彩红张尚弘华北电力大学水利与水电工程学院北京102206

党的十八大以来,在“生态文明建设”“碳达峰碳中和”“黄河流域生态保护和高质量发展”以及“长江经济带高质量发展”等国家战略的指导下,面向清洁能源发展与生态环境保护的复合型水利专业人才需求,对水利专业课程教学内容与教学方法... 详细信息

党的十八大以来,在“生态文明建设”“碳达峰碳中和”“黄河流域生态保护和高质量发展”以及“长江经济带高质量发展”等国家战略的指导下,面向清洁能源发展与生态环境保护的复合型水利专业人才需求,对水利专业课程教学内容与教学方法提出了更高和更新的要求。以培养具有电力特色的复合型水利人才目标为导向,详细阐述了生态水力学的学科发展与学科内涵,深入讨论了课程思政、教学设想等方面的内容,探索了“生态水力学”课程的建设思路,对促进课程教学效果、提升复合型水利人才素质具有重要参考价值。

关键词：人才培养生态水力学课程建设水利工程

基于通道剪枝的YOLOv8n印刷电路板缺陷检测

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无线电工程 2025年第2期55卷 271-280页

作者：杨慧聪陈慈发张上三峡大学水电工程智能视觉监测湖北省重点实验室湖北宜昌443002 三峡大学湖北省建筑质量检测装备工程技术研究中心湖北宜昌443002 三峡大学计算机与信息学院湖北宜昌443002 荆楚理工学院大数据研究中心湖北荆门448000

针对印刷电路板(Printed Circuit Board,PCB)表面缺陷检测任务中模型体积和参数量较大的问题,提出了一种基于通道剪枝的轻量级YOLOv8n网络PCB缺陷检测算法。为有效提升对PCB小目标缺陷的特征提取能力,采用RepViT作为特征提取网络;为提... 详细信息

针对印刷电路板(Printed Circuit Board,PCB)表面缺陷检测任务中模型体积和参数量较大的问题,提出了一种基于通道剪枝的轻量级YOLOv8n网络PCB缺陷检测算法。为有效提升对PCB小目标缺陷的特征提取能力,采用RepViT作为特征提取网络;为提升网络对小目标的关注度,减少神经网络推理过程中的梯度信息重复,将颈部网络的卷积模块替换为Rep-Net with Cross-Stage Partial CSP and ELAN(RepNCSPELAN4);为降低缺陷重叠时检测框失真现象,在预测部分使用Focaler-MPDIoU替换完全交并比(Complete Intersection over Union,CIoU);利用层自适应幅度分数剪枝(Layer Adaptive Magnitude based Pruning,LAMP)方法对融合改进方法的模型进行修剪,去除模型中冗余的梯度信息和权重,减少参数量和浮点运算量,压缩模型体积。实验结果表明,在PCB公开数据集中,经过LAMP之后,该算法相较于YOLOv8n,参数量下降60.8%,模型体积减小50.8%,计算量下降48.8%,平均精度均值(mean Average Precision,mAP)提高3.8%。在提高精度的同时,计算量、参数量和模型体积都低于原模型,满足在低配置设备下的使用需求。

关键词：印刷电路板缺陷小目标模型剪枝轻量化网络损失函数

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Swept Frequency Measurement of Electrooptic Phase Modulators Using Dispersive Fibers

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Chinese Physics Letters 2012年第8期29卷 146-148页

作者： zhang shang-Jian zhang Xiao-Xia LIU Yong State Key Laboratory of Advanced Optical Communication Systems and Networks School of Optoelectronic InformationUniversity of Electronic Science&Technology of ChinaChengdu 610054

A novel method based on the use of dispersive fibers is proposed and experimentally demonstrated for measuring the high-frequency modulation index,as well as the half-wave voltage,of electro-optic phase *** dispersion causes the phase modulated signal to become intensity modulated,which allows for the high resolution swept frequency measurement of phase modulators,using a vector network *** proposed method holds without the restriction of small-signal approximation,which is applicable for the measurement at different driving levels and operating wavelengths.

关键词： holds phase driving

Optimization Algorithm for Reduction the Size of Dixon Resultant Matrix:A Case Study on Mechanical Application

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Computers, Materials & Continua 2019年第2期58卷 567-583页

作者： shang zhang Seyedmehdi Karimi Shahaboddin Shamshirband Amir Mosavi College of Computer and Information Technology China Three Gorges UniversityYichangChina Department of Mathematics Jouybar branchIslamic Azad UniversityJouybarIran Department for Management of Science and Technology Development Ton Duc Thang UniversityHo Chi Minh CityVietnam Faculty of Information Technology Ton Duc Thang UniversityHo Chi Minh CityVietnam Department Institute of Structural Mechanics Bauhaus University of WeimarGermany Institute of Automation Kando Kalman Faculty of Electrical EngineeringObuda University1431 BudapestHungary

In the process of eliminating variables in a symbolic polynomial system,the extraneous factors are referred to the unwanted parameters of resulting *** paper aims at reducing the number of these factors via optimizing the size of Dixon *** optimal configuration of Dixon matrix would lead to the enhancement of the process of computing the resultant which uses for solving polynomial *** do so,an optimization algorithm along with a number of new polynomials is introduced to replace the polynomials and implement a complexity ***,the monomial multipliers are optimally positioned to multiply each of the ***,through practical implementation and considering standard and mechanical examples the efficiency of the method is evaluated.

关键词： Dixon resultant matrix symbolic polynomial system elimination theory optimization algorithm computational complexity

Admissibility of Linear Estimators with Respect to Inequality Constraints Under Some Loss Functions

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Acta Mathematicae Applicatae Sinica 2017年第4期33卷 1073-1082页

作者： shang-li zhang Hong QIN Chang-chun WU School of Science Beijing Jiaotong University Faculty of Mathematics and Statistics Central China Normal University School of Mathematics and Information Jiaxing University

In this paper, we study the issue of admissibility of linear estimated functions of parameters in the multivariate linear model with respect to inequality constraints under a matrix loss and a matrix balanced loss. Under the matrix loss, when the model is not constrained, the results in the class of non-homogeneous linear estimators [Xie, 1989, Chinese Sci. Bull., 1148-1149; Xie, 1993, J. Multivariate Anal., 1071-1074] showed that the admissibility under the matrix loss and the trace loss is equivalent. However, when the model is constrained by the inequality constraints, we find this equivalency is not tenable, our result shows that the admissibility of linear estimator does not depend on the constraints again under this matrix loss, but it is contrary under the trace loss [Wu, 2008, Linear Algebra Appl., 2040-2048], and it is also relative to the constraints under another matrix loss [He, 2009, Linear Algebra Appl., 241-250]. Under the matrix balanced loss, the necessary and sufficient conditions that the linear estimators are admissible in the class of homogeneous and non-homogeneous linear estimators are obtained, respectively. These results will support the theory of admissibility on the linear model with inequality constraints.

关键词： growth curve model linear estimation admissibility incomplete ellipsoidal restriction

High-precision parallel computing model of solute transport based on GPU acceleration

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Journal of Hydrodynamics 2024年第1期36卷 202-212页

作者： shang-hong zhang Rong-qi zhang Wen-da Li Xi-yan Yang Yang Zhou School of Water Resources and Hydropower Engineering North China Electric Power UniversityBeijing102206China Hubei Key Laboratory of Intelligent Yangtze and Hydroelectric Science China Yangtze Power Co.Ltd.Yichang443133China

The scenario simulation analysis of water environmental emergencies is very important for risk prevention and control,and emergency *** quickly and accurately simulate the transport and diffusion process of high-intensity pollutants during sudden environmental water pollution events,in this study,a high-precision pollution transport and diffusion model for unstructured grids based on Compute Unified Device Architecture(CUDA)is *** finite volume method of a total variation diminishing limiter with the Kong proposed r-factor is used to reduce numerical diffusion and oscillation errors in the simulation of pollutants under sharp concentration conditions,and graphics processing unit acceleration technology is used to improve computational *** advection diffusion process of the model is verified numerically using two benchmark cases,and the efficiency of the model is evaluated using an engineering *** results demonstrate that the model perform well in the simulation of material transport in the presence of sharp ***,it has high computational *** acceleration ratio is 46 times the single-thread acceleration effect of the original *** efficiency of the accelerated model meet the requirements of an engineering application,and the rapid early warning and assessment of water pollution accidents is achieved.

关键词： Pollution transport and diffusion model parallel computing Compute Unified Device Architecture(CUDA) pollution event