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Damage Diagnosis of Bleacher Based on an Enhanced Convolutional Neural Network with Training Interference

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Structural Durability & Health Monitoring 2024年第3期18卷 321-339页

作者： Chaozhi Cai Xiaoyu Guo Yingfang Xue Jianhua Ren School of Mechanical and Equipment Engineering Hebei University of EngineeringHandan056038China

Bleachers play a crucial role in practical engineering applications, and any damage incurred during their operationposes a significant threat to the safety of both life and property. Consequently, it becomes imperative to conductdamage diagnosis and health monitoring of bleachers. The intricate structure of bleachers, the varied types ofpotential damage, and the presence of similar vibration data in adjacent locations make it challenging to achievesatisfactory diagnosis accuracy through traditional time-frequency analysis methods. Furthermore, field environmentalnoise can adversely impact the accuracy of bleacher damage diagnosis. To enhance the accuracy and antinoisecapabilities of bleacher damage diagnosis, this paper proposes improvements to the existing ConvolutionalNeural Network with Training Interference (TICNN). The result is an advanced Convolutional Neural Networkmodel with superior accuracy and robust anti-noise capabilities, referred to as Enhanced TICNN (ETICNN).ETICNN autonomously extracts optimal damage-sensitive features from the original vibration data. To validatethe superiority of the proposed ETICNN, experiments are conducted using the bleacher model from Qatar Universityas the subject. Comparative studies under identical experimental conditions involve TICNN, Deep ConvolutionalNeural Networks with wide first-layer kernels (WDCNN), and One-Dimensional ConvolutionalNeural Network (1DCNN). The experimental findings demonstrate that the ETICNN model achieves the highestaccuracy, approximately 99%, and exhibits robust classification abilities in both Phases I and II of the damagediagnosis experiments. Simultaneously, the ETICNN model demonstrates strong anti-noise capabilities, outperformingTICNN by 3% to 4% and surpassing other models in performance.

关键词： Bleacher vibration signal damage diagnosis convolutional neural network anti-noise ability

Ti-Al反应扩散机制及动力学研究进展(下)

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稀有金属材料与工程 2024年第6期53卷 2067-2082页

作者：张建宇陈亚宇杨国强吕征刘宏基马鹏辉曾洪涛李河宗河北工程大学机械与装备工程学院河北邯郸056038 河北工程大学河北省智能工业装备技术重点实验室河北邯郸056038 河北工程大学材料科学与工程学院河北邯郸056038

通过Ti和Al制备的Ti-Al系金属间化合物及复合材料由于具有优异的物理、化学和力学性能,在航空航天、汽车以及其它领域具有良好的应用前景。这些材料包括TiAl_(3)、γ-TiAl和α_(2)-Ti_(3)Al等金属间化合物,以及Ti/Al、Ti/α_(2)-Ti_(3)A... 详细信息

通过Ti和Al制备的Ti-Al系金属间化合物及复合材料由于具有优异的物理、化学和力学性能,在航空航天、汽车以及其它领域具有良好的应用前景。这些材料包括TiAl_(3)、γ-TiAl和α_(2)-Ti_(3)Al等金属间化合物,以及Ti/Al、Ti/α_(2)-Ti_(3)Al、Ti/γ-TiAl、Ti/TiAl_(3)、Ti/TiAl_(3)/Al和Al/TiAl_(3)等金属-金属或金属-金属间化合物复合材料。在上述材料的制备过程中,会涉及到各种Ti-Al反应扩散过程。因此,对Ti-Al反应扩散机理及动力学的深入理解,有助于合理高效地制备Ti-Al系金属间化合物及复合材料。目前对Ti-Al反应扩散机理及动力学的研究非常广泛,但很多结论仍存在争议。本文(下)部分系统综述了Ti-Al反应扩散动力学的研究现状,并对其未来的研究方向进行了展望。

关键词： Ti-Al 反应扩散动力学固相反应固-液反应

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Characteristics and stability of oxide+carbonitride in H13 steel at 1250℃

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Journal of Iron and Steel Research International 2024年第1期31卷 134-142页

作者： Xiao-lin Sun Han-jie Guo Jing Guo Fei Wang Dong Xu Gao-yang Song Shuai Wang School of Materials Science and Engineering Hebei University of EngineeringHandan056038HebeiChina School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China High Temperature Materials Research Institute Central Iron and Steel Research Institute Co.Ltd.Beijing100081China Technology Innovation Center for High Quality Cold Heading Steel of Hebei Province Hebei University of EngineeringHandan056038HebeiChina

The morphology,size,quantity,and composition of complex oxide+carbonitride in H13 steel held at 1250℃for 5,10,and 15 h were *** results show that the ratio and number of complex carbonitrides with cores in H13 steel are gradually increased when holding at 1250℃compared with those in the original H13 steel,and the core size *** are one or more oxide cores in(Ti_(x),V_(1-x))(Cy,N_(1-y)),including xCaO·zAl_(2)O_(3),xCaO·yMgO·zAl_(2)O_(3),and CaO after holding at 1250℃,in addition to MgO·Al_(2)O_(3)and Al_(2)O_(3)in the original *** equilibrium temperature for(Ti_(x),V_(1-x))(Cy,N_(1-y))precipitation at the solidification front and decomposition in the solid state was theoretically analyzed,which was affected by the x value and the product of Ti and N contents in H13 ***,the composition of(Ti_(x),V_(1-x))(Cy,N_(1-y))is influenced by the oxide *** is convinced that(Ti_(x),V_(1-x))(Cy,N_(1-y))with oxide cores has a higher stability,especially for oxides with a high Al_(2)O_(3)*** treatment at high temperature facilitates a more reasonable analysis of oxide+carbonitride,and the generation mechanism of oxide+carbonitride was discussed.

关键词： Complex carbonitride Decomposition Oxide core Characteristic Stability

融合PM_(2.5)浓度遥感生态指数的峰峰矿区生态环境质量时空特征及驱动力分析

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环境科学 2024年第10期45卷 5900-5911页

作者：张靓涵张未赵安周孙利辉河北工程大学矿业与测绘工程学院邯郸056038 邯郸市自然资源空间信息重点实验室邯郸056038

峰峰矿区作为我国重要的煤炭主产区,其煤炭开采和利用对生态环境造成了严重的影响,深入了解该地区生态环境质量时空演变及其驱动因素对于推进煤炭型城市转型具有重要意义.基于GEE平台的Landsat数据,构建了2000~2020年峰峰矿区新型遥感... 详细信息

峰峰矿区作为我国重要的煤炭主产区,其煤炭开采和利用对生态环境造成了严重的影响,深入了解该地区生态环境质量时空演变及其驱动因素对于推进煤炭型城市转型具有重要意义.基于GEE平台的Landsat数据,构建了2000~2020年峰峰矿区新型遥感生态指数(RSEInew),结合趋势分析和地理探测器等方法评估RSEInew的时空演变规律及驱动要素.结果表明:①2000~2020年峰峰矿区的RSEInew呈现波动增加趋势(trend=0.0022),其生态环境质量良和优等级占比呈现增加的趋势,其值由2000年的24.80%上升到2020年的65.54%;②RSEInew等级变化表明2000~2020年峰峰矿区生态环境质量等级显著改善(3和4)的比例为10.21%,主要分布在其西北部的和村镇和义井镇等地;显著退化(-3和-4)的比例仅为1.58%,主要零星分布在东部的临水镇和大社镇;③2000~2020年期间RSEInew值呈显著增加(P<0.05)的面积占比为18.29%,主要集中分布在中北部地区以及西部边缘地带;显著减小(P<0.05)的面积占比为9.25%,主要集中在峰峰矿区东部地区.变异系数结果表明,RSEInew高波动的地区主要集中在峰峰矿区的中部以及东部的彭城镇和临水镇;④从影响因素来看,2000~2020年期间土地利用类型(X6)的q值均值为0.290,远大于其他因子.社会经济要素的q值呈现上升的趋势,表明该地区生态环境质量的空间分布受人类活动的影响越来越强.交互作用结果表明土地利用变化是峰峰矿区生态环境质量的关键影响要素.

关键词： GEE平台新型遥感生态指数(RSEInew) 时空演变驱动因素峰峰矿区

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基于Frenet坐标下改进人工势场法的无人车局部路径规划

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兵工学报 2024年第7期45卷 2097-2109页

作者：姬鹏郭明皓河北工程大学机械与装备工程学院河北邯郸056038

人工势场法由于运算量小、精度高,广泛应用于无人车的局部路径规划。针对传统人工势场法存在目标不可达、局部最小值及陷入U型障碍物的问题,提出一种基于Frenet坐标系下改进人工势场法的路径规划算法。构建Frenet坐标系来表述车辆避障运... 详细信息

人工势场法由于运算量小、精度高,广泛应用于无人车的局部路径规划。针对传统人工势场法存在目标不可达、局部最小值及陷入U型障碍物的问题,提出一种基于Frenet坐标系下改进人工势场法的路径规划算法。构建Frenet坐标系来表述车辆避障运动,简化规划模型,解决路径规划中车辆与所在道路相对位置不易表述的问题。提出安全椭圆模型和预测距离的概念来调整势场影响区域,加入基于Frenet坐标系下的参考线势场及动态速度势场改进斥力场函数,解决车辆在静态和动态下的避障问题。利用数学仿真软件进行仿真,以不同车速在直道和弯道场景中对所提出的路径规划方法进行静态和动态避障仿真实验。研究结果表明:不同车速下的前轮转角、横摆角速度均控制在较小范围内,改进算法可以有效解决传统人工势场法的缺陷,同时与快速搜索随机树(Rapidly-exploring Random Tree,RRT)算法相比,其在避障过程中路径规划计算效率提高了42.8%,改进算法优势明显。

关键词：无人车局部路径规划人工势场法 Frenet坐标系

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Notably Accelerated Nano-Bainite Transformation via Increasing Undissolved Carbides Content on GCr15Si1Mo Bearing Steel

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Acta Metallurgica Sinica(English Letters) 2024年第4期37卷 703-712页

作者： Yan-Hui Wang Hua-Qiang Sun Wen-Jing Feng Lei-Jie Zhao Xiang Chen Qing-An Chen Hai-Tao Sun Jian-Jun Wang Zhi-Nan Yang Key Laboratory of Intelligent Industrial Equipment Technology of Hebei Province School of Mechanical and Equipment EngineeringHebei University of EngineeringHandan056038China Collaborative Innovation Center for Modern Equipment Manufacturing of Jinan New Area Hebei University of EngineeringHandan056038China School of Materials Science and Engineering Tsinghua UniversityBeijing100084China Avic Shang da Superalloys Company Limited Xingtai054800China National Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan UniversityQinhuangdao066004China

In this study, a high-carbon nano-bainitic GCr15Si1Mo bearing steel was investigated. Specifically, the effects of content and size of undissolved carbides on the microstructure and transformation kinetics of nano-bainite were analyzed. The results demonstrated that after prolonged austempering at low temperatures, the mixed microstructure composed of nano-bainite (NB), undissolved carbides (UC), and retained austenite (RA) was obtained in GCr15SiMo steel. When the experimental steel was austenitized at 900 ℃, the undissolved carbides gradually dissolved until reaching a stable state with increasing holding time. Furthermore, at the same austempering temperature, despite different volume fractions of undissolved carbides in the substrate, the volume fractions of nano-bainite in the final microstructures remained essentially the same. Moreover, the higher the content of undissolved carbides in steel, the faster the transformation rate of nano-bainite and the shorter the total transformation time.

关键词： Nano-bainite Undissolved carbides Bainitic transformation kinetics Carbon concentration

黔西北煤田晚二叠世煤关键金属Li-Nb-Ta富集特征及成因机制

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地质学报 2024年第8期98卷 2316-2335页

作者：金超刘浪涛张小刚高帅坡程智伟李斌斌周进伟陈永龙河北省资源勘测研究重点实验室河北邯郸056038 河北工程大学地球科学与工程学院河北邯郸056038

关键金属是当今社会必须的但是安全供应存在高风险的一类金属的总称。煤因富含有机质往往能够富集关键金属,特殊地质条件下能形成煤型关键金属矿床。很多研究表明我国西南地区晚二叠世含煤地层富含多种关键金属,但是其富集特征和形成机... 详细信息

关键金属是当今社会必须的但是安全供应存在高风险的一类金属的总称。煤因富含有机质往往能够富集关键金属,特殊地质条件下能形成煤型关键金属矿床。很多研究表明我国西南地区晚二叠世含煤地层富含多种关键金属,但是其富集特征和形成机制仍然不清楚。本文以贵州黔西北煤田泰来煤矿上二叠统龙潭组9#煤层为研究对象,系统采集了煤层及顶底板样品,利用粉末X射线衍射仪对样品进行了矿物类别分析,利用X射线荧光光谱仪对样品进行了主量元素分析,利用电感耦合等离子体质谱仪对样品进行了微量元素分析。实验结果表明样品中的主要矿物包括高岭石、石英、伊利石、黄铁矿、锐钛矿、金红石、方解石、白云石、钠云母和钠长石等。含量较多的主量元素氧化物为SiO_(2)、TiO_(2)、Al_(2)O_(3)和Fe_(2)O_(3),存在富集的微量元素为Li、Nb、Ta、Zr、Hf、Sn、Th和In,其中Li、Nb和Ta的含量分别为世界煤均值的7.9倍、7.8倍和8.7倍。沉积物源和矿物赋存特征分析表明,峨眉山中性火山岩和高钛玄武岩对含煤盆地的物质供应具有一定的贡献,沉积之后的热液活动对该煤层关键金属的富集具有重要作用。

关键词：黔西北煤田晚二叠世煤关键金属元素 Li-Nb-Ta富集

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Strong electron correlation-induced Mott-insulating electrides of Ae_(5)X_(3)(Ae=Ca,Sr,and Ba;X=As and Sb)

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Matter and Radiation at Extremes 2024年第3期9卷 74-82页

作者： Ya Xu Lu Zheng Yunkun Zhang Zhuangfei Zhang QianQian Wang Yuewen Zhang Liangchao Chen Chao Fang Biao Wan Huiyang Gou Key Laboratory of Material Physics of Ministry of Education School of Physics and Laboratory of Zhongyuan LightZhengzhou UniversityZhengzhou 450052China School of Mechanical and Equipment Engineering Hebei University of EngineeringHandan 056038China Center for High Pressure Science and Technology Advanced Research Beijing 100094China

The presence of interstitial electrons in electrides endows them with interesting attributes,such as low work function,high carrier concentration,and unique magnetic *** knowledge and understanding of electrides are thus of both scientific and technological ***,we employ first-principles calculations to investigate Mott-insulating Ae_(5)X_(3)(Ae=Ca,Sr,and Ba;X=As and Sb)electrides with Mn_(5)Si_(3)-type structure,in which half-filled interstitial electrons serve as ions and are *** Mott-insulating property is induced by strong electron correlation between the nearest interstitial electrons,resulting in spin splitting and a separation between occupied and unoccupied *** half-filled antiferromagnetic configuration and localization of the interstitial electrons are critical for the Mott-insulating properties of these *** with that in intermetallic electrides,the orbital hybridization between the half-filled interstitial electrons and the surrounding atoms is weak,leading to highly localized magnetic centers and pronounced correlation ***,the Mott-insulating electrides Ae_(5)X_(3)have very large indirect bandgaps(0.30 eV).In addition,high pressure is found to strengthen the strong correlation effects and enlarge the *** present results provide a deeper understanding of the formation mechanism of Mott-insulating electrides and provide guidance for the search for new strongly correlated electrides.

关键词： intermetallic filled occupied

融合无人机光谱信息与纹理特征的冬小麦综合长势监测

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农业机械学报 2024年第9期55卷 249-261页

作者：承达瑜何伟德付春晓赵伟王建东赵安周河北工程大学矿业与测绘工程学院邯郸056038 河北省水生态文明及社会治理研究中心邯郸056038 河北工程大学水利水电学院邯郸056038 中国农业科学院农业环境与可持续发展研究所北京100081

高效、及时获取作物长势信息对作物生产管理具有重要作用。目前针对小区域农作物长势监测多以无人机光谱信息反演来实现,但综合考虑农作物不同生育期阶段的表面特征信息进行小区域农作物长势监测的方法需进一步研究。本文以冬小麦为研... 详细信息

高效、及时获取作物长势信息对作物生产管理具有重要作用。目前针对小区域农作物长势监测多以无人机光谱信息反演来实现,但综合考虑农作物不同生育期阶段的表面特征信息进行小区域农作物长势监测的方法需进一步研究。本文以冬小麦为研究对象,基于冬小麦株高和叶面积指数(Leaf area index, LAI)按照变异系数法构建综合长势监测指标(Comprehensive growth monitoring indicators, CGMI),提出一种融合无人机光谱信息与纹理特征的冬小麦综合长势监测方法。以搭载多光谱镜头的无人机获取冬小麦4个生育期影像,得到12种植被指数和各波段的8类纹理特征。采用Person相关性分析方法,筛选出与CGMI相关性较好的植被指数与纹理特征,进而采用随机森林回归(Random forest, RF)、偏最小二乘回归(Partial least squares regression, PLSR)、支持向量机回归(Support vector regression, SVR)3种机器学习方法分别构建基于植被指数和基于植被指数与纹理特征的2个长势监测模型,通过比较得到较优长势监测模型,最终获得研究区冬小麦长势空间分布信息。结果表明:3种机器学习方法中,基于植被指数与纹理特征的SVR长势监测模型精度最高(训练集R^(2)为0.789,MAE为0.03,NRMSE为4.8%,RMSE为0.04),与基于植被指数的SVR长势监测模型相比,该模型决定系数提高5.1%,平均绝对误差降低3.3%,标准均方根误差降低8.3%,均方根误差降低10%。研究结果证明该方法精确、可靠,可为冬小麦长势监测提供参考。

关键词：冬小麦综合长势监测指标无人机多光谱纹理特征

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