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热轧板带感应加热建模及应用

塑性工程学报 2025年第1期32卷 84-91页

作者：逯少波李盼盼李伟王涛太原理工大学机械与运载工程学院山西太原030024 先进金属复合材料成型技术与装备教育部工程研究中心山西太原030024 中冶南方工程技术有限公司湖北武汉430223

为准确分析感应加热在板带热轧中的应用,通过对集肤深度内离散单元的功率进行积分,确定了每个单元的内热源强度,对集肤深度范围内外设置不同的二维差分方程,利用Python语言建立了感应加热差分模拟计算模型。利用COMSOL有限元分析软件对... 详细信息

为准确分析感应加热在板带热轧中的应用,通过对集肤深度内离散单元的功率进行积分,确定了每个单元的内热源强度,对集肤深度范围内外设置不同的二维差分方程,利用Python语言建立了感应加热差分模拟计算模型。利用COMSOL有限元分析软件对热轧板带的感应加热过程进行了现场对应工况条件下的仿真,并将仿真结果与差分模拟结果和现场实测数据进行对比,得到的温度变化曲线具有较好的一致性,误差不大于5%。着重分析了集肤深度对于板带传热过程的影响以及板带最高温度在特定条件下出现在次表面的原因。该差分模拟具有较高精度与较快运算速度,可以满足日常工程实践要求。

关键词：热轧板带感应加热差分模拟 COMSOL仿真传热机理

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时空特征变分学习的交通流预测模型

控制理论与应用 2025年第1期42卷 158-166页

作者：欧阳毅汤文燕邵泳博黎晏伶浙江工商大学管理工程与电子商务学院浙江杭州310018

交通流量时空预测是智能交通系统的关键任务.针对城市交通流序列的非线性和多模态特性,本文提出了一种基于时空特征融合的变分学习模型(ST-FVAE),采用局部时空特征融合和全局特征融合两个阶段对具有图空间拓扑特性的交通流数据进行预测... 详细信息

交通流量时空预测是智能交通系统的关键任务.针对城市交通流序列的非线性和多模态特性,本文提出了一种基于时空特征融合的变分学习模型(ST-FVAE),采用局部时空特征融合和全局特征融合两个阶段对具有图空间拓扑特性的交通流数据进行预测.局部特征融合模块由时间卷积残差单元和图卷积神经网络(GCN)构成,提取交通节点的局部时间特征信息,并利用GCN将空间拓扑信息嵌入局部时间特征信息中.通过基于局部时空图特征融合的变分自编码器交通流预测模型,学习全局时空相关性特征.在全局时空特征融合变分自编码器的学习过程中,为使Q分布能够逼近实际数据P分布,通过最大化似然函数的变分推断证据下界(ELbo)使得两个分布之间的KL散度最小化,提出了计算分布期望的KL差异构造训练损失函数的方法,进一步提高预测准确率.通过对交通流数据集和交通速度数据集的预测实验结果表明:本文提出的方法在交通流量和速度的预测方面都具有较好的预测特性,对于30 min和60 min的预测鲁棒性更好.

关键词：交通流预测时空融合变分自编码器图卷积

Lens coloboma with bilateral ectopia lentis in marfan syndrome:a case report

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International Journal of Ophthalmology(English edition) 2025年第2期18卷 358-361页

作者： Zhen-bo Zhao Kai-Li Tang Yu-Xi Ding Ji-Kun Yang Huan-Ping Wang Li-Wei ma Aier Eye Medical Center of Anhui Medical University Hefei 230031Anhui ProvinceChina Aier Excellence Eye Hospital Shenyang 110000Liaoning ProvinceChina

Dear Editor,We report a rare case of lens coloboma and several notches with bilateral ectopia lentis in marfan *** case was approved by the Ethics Committee of Aier Excellence Eye Hospital(2023KJB0004).Written informed consent was obtained from the *** coloboma and marfan syndrome are of low incidence and seldom observed in the clinic.

关键词： marfan bilateral rare

A marcinkiewicz criterion for L^(p)-multipliers related to Schrodinger operators with constant magnetic fields

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Science China mathematics 2015年第2期58卷 389-404页

作者： DENG Liu Rui ma bo Lin LIU shao Yue College of Economics and management Hunan Normal University College of mathematics and Information Engineering Jiaxing University Department of mathematics Xiangtan University

In this paper,we follow Dappa’s work to establish the marcinkiewicz criterion for the spectral multipliers related to the Schrdinger operator with a constant magnetic *** prove that if m and m′are locally absolutely continuous on(0,∞)and ‖m‖∞+sup j∈Z2j 2i+1 r|m′′(r)|drbounded on Lpfor 2n/(n+3)mates for the generalized Littlewood-Paley functions of the spectral representation of the Schrdinger operator with a constant magnetic field.

关键词： magnetic Schrodinger operator spectral multiplier Riesz means

Properties of doped ZnO transparent conductive thin films deposited by RF magnetron sputtering using a series of high quality ceramic targets

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Rare Metals 2008年第1期27卷 32-35页

作者： LIN Wei ma Ruixin shao Wei KANG bo WU Zhongliang Department of Nonferrous Metallurgy University of Science and Technology Beijing Beijing 100083 China

To obtain high transmittance and low resistivity ZnO transparent conductive thin films,a series of ZnO ceramic targets（ZnO：Al,ZnO：（Al,Dy）,ZnO：（Al,Gd）,ZnO：（Al,Zr）,ZnO：（Al,Nb）,and ZnO：（Al,W）） were fabricated and used to deposit thin films onto glass substrates by radio frequency（RF） magnetron sputtering.X-ray diffraction（XRD） analysis shows that the films are polycrystalline fitting well with hexagonal wurtzite structure and have a preferred orientation of the（002） *** transmittance of above 86% as well as the lowest resistivity of 8.43 × 10^-3 Ω·cm was obtained.

关键词： ZnO transparent conductive thin film RF magnetron sputtering optical properties electrical properties

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水利工程中数字孪生虚拟实体轻量化研究

中国农村水利水电 2025年第1期 168-174页

作者：孙少楠董国玉焦红波李博宇华北水利水电大学河南郑州450046 中国电建集团北京勘测设计研究院有限公司北京100024

近年来,数字孪生技术在水利领域正在快速发展。其中,数字孪生数据底板存储着水利工程全生命周期中的信息,存在数据量庞大、管理复杂、更新成本增加等问题。同时,以WebGL为核心引擎渲染加载的应用层数字孪生平台受网络带宽和计算机性能... 详细信息

近年来,数字孪生技术在水利领域正在快速发展。其中,数字孪生数据底板存储着水利工程全生命周期中的信息,存在数据量庞大、管理复杂、更新成本增加等问题。同时,以WebGL为核心引擎渲染加载的应用层数字孪生平台受网络带宽和计算机性能的限制,面临着轻量化处理的挑战。针对数字孪生虚拟实体维度中的几何模型数据,利用改进QEM(Quadric Error Metrics,二次误差测度)算法和Low-Poly算法进行轻量化处理,选取水轮机导水机构作为案例,研究在满足数字孪生业务需求下的最优简化程度。结果表明:轻量化的处理是必要的;轻量化处理后的模型文件大小大幅度减小;在满足数字孪生精细度等级4个精度等级的简化程度的上限分别为原始数据、40%左右、70%左右、98%左右。

关键词：数字孪生水利工程轻量化 QEM

Interfacial dislocations dominated lateral growth of long-period stacking ordered phase in Mg alloys

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Journal of materials Science & Technology 2021年第2期61卷 114-118页

作者： Qjanqian Jin Xiaohong shao Shijian Zheng Yangtao Zhou bo Zhang Xiuliang ma Shenyang National Laboratory for materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of materials Science and Engineering Lanzhou University of TechnologyLanzhou730050China School of materials Science and Engineering Research Institute for Energy Equipment MaterialsHebei University of TechnologyTianjin300130China

Understanding the interface between strengthening precipitates and matrix in alloys, especially at the atomic level, is a critical issue for tailoring the precipitate strengthening to achieve desired mechanical properties. Using high-resolution scanning transmission electron microscopy, we here clarify the semicoherent interfaces between the matrix and long-period stacking ordered(LPSO) phases, including 18 R and 14 H, in Mg–Zn–Y alloys. The LPSO/Mg interface features the unique configuration of the Shockley partial dislocations, which produces a near zero macroscopic strain because the net Burgers vectors equal zero. The 18 R/Mg interface characterizes a dissociated structure that can be described as a narrow slab of 54 R. There are two dislocation arrays accompanied to the 18 R/54 R and 54 R/Mg interface, resulting a slight deviation(about 2.3°). The 14 R/Mg interface exhibits the dislocation pairs associated with solute atoms. We further evaluate the stability and morphology of the corresponding interfaces based on elastic interaction, via calculating the mutual strong interactions between dislocation arrays, as well as that between the dislocations and solute atoms. The synchronized migration of interfacial dislocations and solute atoms, like move-drag behavior, dominates the lateral growth of LPSO phases in Mg alloys.

关键词： magnesium alloys Long-period stacking ordered phases Dislocations Heterogeneous interface

The GECAM ground search system for gamma-ray transients

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Science China(Physics,Mechanics & Astronomy) 2025年第3期68卷 161-174页

作者： Ce Cai Yan-Qiu Zhang shao-Lin Xiong Ping Wang Jian-Hui Li Xiao-bo Li Cheng-Kui Li Yue Huang Shi-Jie Zheng Li-Ming Song Shuo Xiao Qi-Bin Yi Yi Zhao Sheng-Lun Xie Rui Qiao Yan-Qi Du Zhi-Wei Guo Wang-Chen Xue Chao Zheng Jia-Cong Liu Chen-Wei Wang Wen-Jun Tan Yue Wang Jin-Peng Zhang Chao-Yang Li Guo-Ying Zhao Xiao-Yun Zhao Xiao-Lu Zhang Zhen Zhang Wen-Xi Peng Xiang ma Jing-Yan Shi Dong-Ya Guo Jin Wang Xin-Qiao Li Xiang-Yang Wen Zheng-Hua An Fan Zhang College of Physics and Hebei Key Laboratory of Photophysics Research and Application Hebei Normal UniversityShijiazhuang050024China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing100049China University of Chinese Academy of Sciences Beijing100049China School of Physics and Electronic Science Guizhou Normal UniversityGuiyang550001China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal UniversityGuiyang550001China School of Physics and Optoelectronics Xiangtan UniversityXiangtan411105China School of Computer and Information Dezhou UniversityDezhou253023China Institute of Astrophysics Central China Normal UniversityWuhan430079China

In the era of time-domain,multi-messenger astronomy,the detection of transient events on the high-energy electromagnetic sky has become more important than *** gravitational wave high-energy electromagnetic counterpart all-sky monitor(GECAM)is a dedicated mission to monitor gamma-ray transients,launched in December,2020.A real-time on-board trigger and location software,using the traditional signal-to-noise ratio(SNR)method for blind search,is constrained to relatively bright signals due to the limitations in on-board computing resources and the need for real-time *** this work,we developed a ground-based pipeline for GECAM to search for various transients,especially for weak bursts missed by on-board *** pipeline includes both automatic and manual mode,offering options for blind search and targeted *** targeted search is specifically designed to search for interesting weak bursts,such as gravitational wave-associated gamma-ray bursts(GRBs).From the ground search of the data in the first year,GECAM has been triggered by 54 GRBs and other transients,including soft gamma-ray repeaters,X-ray binaries,solar flares,terrestrial gamma-ray *** report the properties of each type of triggers,such as trigger time and light *** this search pipeline and assuming a soft Band spectrum,the GRB detection sensitivity of GECAM is increased to about 1.1×10^(-8)erg cm^(-2)s^(-1)(10-1000 ke V,burst duration of 20 s).These results demonstrate that the GECAM ground search system(both blind search and targeted search)is a versatile pipeline to recover true astrophysical signals which were too weak to be found in the on-board search.

关键词： gamma-ray sources gravitational waves data analysis gamma-ray telescopes

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青藏线双源动车组黏着适应性研究

西南交通大学学报 2025年第1期60卷 214-224页

作者：王波罗世辉王晨曲天威马卫华雷成西南交通大学轨道交通运载系统全国重点实验室四川成都610031 郑州铁路职业技术学院河南省轨道交通智能安全工程技术研究中心河南郑州451460 石家庄铁道大学机械工程学院河北石家庄050043 中车大连机车车辆有限公司辽宁大连116022

为了分析运行效率更高的双源动车组在青藏线(格尔木—拉萨段)运行的可行性,建立机车动力学模型并进行了验证;采用动力学方法研究了双源动车组机车(动车)和青藏线成熟运营的HXN3内燃机车在直线段、曲线段和坡道上的牵引黏着系数、牵引力... 详细信息

为了分析运行效率更高的双源动车组在青藏线(格尔木—拉萨段)运行的可行性,建立机车动力学模型并进行了验证;采用动力学方法研究了双源动车组机车(动车)和青藏线成熟运营的HXN3内燃机车在直线段、曲线段和坡道上的牵引黏着系数、牵引力、蠕滑率与速度之间的关系;通过对比2个机车的动力学响应,验证牵引工况下双源动车组的黏着特性.通过分析可以发现:1)机车的牵引黏着系数与机车的牵引力成正比,当车速在40~120km/h时,双源动车组机车的黏着系数由0.19降低至0.09,黏着富裕度则由59.0%提高至85.7%;2)在直线段和坡道情况下,双源动车组的黏着富裕度均大于HXN3机车,对适应恶劣外界环境引起的轮轨黏着下降能力更强,对高原环境的适应性更优;3)曲线段,忽略结构引起的黏降差异,R300m曲线时,双源动车组和HXN3型机车的黏降幅度分别为6.3%和6.8%,R800 m曲线时,HXN3型机车曲线黏降幅度为3.0%,而双源动车组低于限值,可以保证有足够的黏着.

关键词：高原铁路内电双源内燃机车动力学牵引黏着