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Journal of Iron and Steel Research(International) 2024年第3期31卷 767-777页

作者： Hong-bin Dai jian miao Jia-xin Lin School of Materials Science and Engineering Harbin University of Science and TechnologyHarbin 150040HeilongjiangChina

The welding arc,as a carrier for the conversion of electrical energy to thermal energy,has a direct impact on the quality of welding by its properties and *** the tungsten inert gas(TIG)welding process under the condition of Ar-He alternating gas supply,the arc is alternately converted between Ar arc and He arc with an alternating gas supply cycle,which has obvious arc change *** FLUENT software was used to numerically simulate the characteristics of the TIG arc under the condition of alternating gas supply,and the arc temperature field,arc pressure,electric potential and current density distribution under the condition of alternating gas supply were *** with the real-time data of arc pressure measured by the water-cooled copper plate with holes,it is proved that the TIG arc has obvious dynamic characteristics under the condition of Ar-He alternating gas *** unique dynamic TIG arc acts on the 5A06 aluminum alloy weld,causing the molten pool to stir,resulting in uniform microstructure and grain refinement at the weld,and thereby improving the mechanical properties of the welded joint.

关键词： Alternating gas supply Grain refinement Numerical simulation Tungsten argon arc morphology Microstructure Mechanical property

Remaining useful life prediction for train bearing based on an ILSTM network with adaptive hyperparameter optimization

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Transportation Safety and Environment 2024年第2期6卷 75-86页

作者： Deqiang He Jingren Yan Zhenzhen Jin Xueyan Zou Sheng Shan Zaiyu Xiang jian miao State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures Guangxi Key Laboratory of Manufacturing System&Advanced Manufacturing Tec hnologySc hool of Mec hanical EngineeringGuangxi Univ ersityNanning 530004GuangxiChina Zhuzhou CRRC Times Electric Co. Ltd.Zhuzhou 412001HunanChina

Remaining useful life(RUL)prediction for bearing is a significant part of the maintenance of urban rail transit *** RUL is closely linked to the reliability and safety of train running,but the current prediction accuracy makes it difficult to meet the re-quirements of high reliability *** at the problem,a prediction model based on an improved long short-term memory(ILSTM)network is ***,the variational mode decomposition is used to process the signal,the intrinsic mode function with stronger representation ability is determined according to energy entropy and the degradation feature data is constructed com-bined with the time domain ***,to improve learning ability,a rectified linear unit(ReLU)is applied to activate a fully connected layer lying after the long short-term memory(LSTM)network,and the hidden state outputs of the layer are weighted by attention *** Harris Hawks optimization algorithm is introduced to adaptively set the hyperparameters to improve the performance of the ***,the ILSTM is applied to predict bearing *** experimental cases,the better perfor-mance in bearing RUL prediction and the effectiveness of each improving measures of the model are validated,and its superiority of hyperparameters setting is demonstrated.

关键词： train bearing remaining useful life prediction long short-term memory(LSTM) attention mechanism Harris Hawks op-timization(HHO)

Pig pangenome graph reveals functional features of non‑reference sequences

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Journal of Animal Science and Biotechnology 2024年第3期15卷 956-970页

作者： jian miao Xingyu Wei Caiyun Cao Jiabao Sun Yuejin Xu Zhe Zhang Qishan Wang Yuchun Pan Zhen Wang College of Animal Sciences Zhejiang UniversityHangzhou 310058ZhejiangChina Yazhou Bay Science and Technology City Hainan Institute of Zhejiang UniversityYazhou DistrictBuilding 11Yongyou Industrial ParkSanya 572025HainanChina

Background The reliance on a solitary linear reference genome has imposed a significant constraint on our compre-hensive understanding of genetic variation in *** constraint is particularly pronounced for non-reference sequences(NRSs),which have not been extensively *** In this study,we constructed a pig pangenome graph using 21 pig assemblies and identified 23,831 NRSs with a total length of 105 *** findings revealed that NRSs were more prevalent in breeds exhibiting greater genetic divergence from the reference ***,we observed that NRSs were rarely found within coding sequences,while NRS insertions were enriched in immune-related Gene Ontology ***,our investigation also unveiled a close association between novel genes and the immune capacity of *** observed substantial differences in terms of frequencies of NRSs between Eastern and Western pigs,and the heat-resistant pigs exhibited a substantial number of NRS insertions in an 11.6 Mb interval on chromosome ***,we discovered a 665 bp insertion in the fourth intron of the TNFRSF19 gene that may be associated with the ability of heat tolerance in South-ern Chinese *** Our findings demonstrate the potential of a graph genome approach to reveal important functional features of NRSs in pig populations.

关键词： Heat tolerance Immune ability Non-reference sequences Pig pangenome

K_(0.5)Na_(0.5)NbO_(3)掺杂对0.94Bi_(0.5)Na_(0.5)TiO_(3)-0.06BaTiO_(3)陶瓷储能性能的影响

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人工晶体学报 2024年第5期53卷 882-888页

作者：苗健邵辉曹瑞龙江苏科技大学材料科学与工程学院镇江212003

采用传统固相反应法制备了K_(0.5)Na_(0.5)NbO_(3)(KNN)掺杂的无铅介电储能陶瓷BNT-BT-KNN,其组分配比为0.94Bi_(0.5)Na_(0.5)TiO_(3)-(0.06-x)BaTiO_(3)-xK_(0.5)Na_(0.5)NbO_(3)(BNT-BT+xKNN,x=0.00~0.04),并研究了KNN掺杂对BNT-BT基陶瓷材料晶相、微观结构、介电、铁电性能及储能的影响。结果表明:在1150℃温度下烧成后的陶瓷样品具有纯的钙钛矿结构,且样品的晶粒均匀致密;介电温谱显示,添加KNN后的BNT-BT铁电陶瓷在T_(m)处的介电峰进一步宽化,表现出更好的温度稳定性和弛豫性;同时随着KNN掺杂量的增加,样品的电滞曲线(P-E曲线)逐渐由“宽胖型”向“细长型”转变,样品的剩余极化强度(P_(r))逐渐降低,从而进一步提高了BNT-BT陶瓷的储能性能。在2 kV/mm的场强下,x=0.03时测得样品的储能密度最佳W_(rec)=0.048 J/cm^(3),对应的储能效率η=43%,显示该材料在储能电容器上具有良好的应用潜力。

关键词： BNT-BT陶瓷 KNN掺杂固相反应法弛豫铁电性能介电性能储能

Collective effects in an incompressible electronic liquid

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National Science Review 2023年第6期10卷 168-182页

作者： jian-jian miao Hui-Ke Jin Yi Zhou Department of Physics The Chinese University of Hong Kong Department of Physics TQM Technische Universitat Munchen Institute of Physics Chinese Academy of Sciences Songshan Lake Materials Laboratory Kavli Institute for Theoretical Sciences & CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of Sciences

Starting from Landau’ s kinetic equation,we show that an electronic liquid in d=2,3 spatial dimensions depicted by a Landau-type effective theory will become incompressible on condition that the Landau parameters satisfy either(ⅰ) 1+F1s/d=0 or(ⅱ) F0s→+∞. Condition(ⅰ) is the Pomeranchuk instability in the current channel and suggests a quantum spin liquid(QSL) state with a spinon Fermi surface;while condition(ⅱ) means that the strong repulsion in the charge channel leads to a conventional charge and thermal *** the collisionless regime(ωτ>>1) and the hydrodynamic regime(ωτ<<1),the zero and first sound modes have been studied and classified by symmetries,including the longitudinal and transverse modes in d=2,3 and the higher angular momentum modes in d=*** sufficient(and/or necessary) conditions of these collective modes have been *** has been demonstrated that some of these collective modes will behave in quite different manners under incompressibility condition(ⅰ) or(ⅱ).Possible nematic QSL states and a hierarchy structure for gapless QSL states have been proposed in d=3.

关键词： quantum spin liquid Landau-type effective theory collective modes zero sound first sound

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基于全基因组选择的高产花生选育方法

中国油料作物学报 2024年第3期46卷 697-702页

作者：郭敏杰邓丽苗建利殷君华任丽开封市农林科学研究院河南开封475000

本研究旨在批量开展花生杂交组配,为高效培育高产花生新品种提供理论指导。利用多年多点百果重和单株生产力的表型数据和深度为10×的重测序数据对220份花生种质进行全基因组选择分析。结果表明,表型数据符合正态分布,基因组数据质控后... 详细信息

本研究旨在批量开展花生杂交组配,为高效培育高产花生新品种提供理论指导。利用多年多点百果重和单株生产力的表型数据和深度为10×的重测序数据对220份花生种质进行全基因组选择分析。结果表明,表型数据符合正态分布,基因组数据质控后获得527469个高质量SNP(single nucleotide polymorphism)位点;基于表型数据,利用GBLUP(genomic best linear unbiased prediction)模型计算单株生产力和百果重的估计育种值;对估计育种值进行标准化,分别赋予70%和30%的权重,获得花生种质个体的综合育种值;综合育种值排名前20的材料共有190个组合,计算两两间的组合综合育种值;基于基因组数据,利用G矩阵计算两两材料间的亲缘关系系数;将组合综合育种值和亲缘关系系数进行标准化,分别赋予80%和20%的权重,计算组配综合得分;根据组配综合得分的排名直接选择亲本配制组合。综上所述,由开农30×开选016组合产生的种质材料适合作高产亲本,利用全基因组选择可高效、准确计算组合间排名,批量选择亲本组合,快速提高育种效率。

关键词：花生高产表型重测序全基因组选择杂交组合

人类命运共同体视域下地方高校大学生国际素养培育探赜

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北部湾大学学报 2024年第1期39卷 63-70页

作者：苗剑黄孙庆黄家庆葛磊北部湾大学广西钦州535011

培养大学生的国际素养,是构建人类命运共同体赋予高校的使命,是高校国际化建设发展的题中之义,是当代大学生实现个人发展价值的诉求。地方高校培育提升大学生的国际素养,明确大学生应有的国际素养要素内涵是前提,充分认识培育大学生国... 详细信息

培养大学生的国际素养,是构建人类命运共同体赋予高校的使命,是高校国际化建设发展的题中之义,是当代大学生实现个人发展价值的诉求。地方高校培育提升大学生的国际素养,明确大学生应有的国际素养要素内涵是前提,充分认识培育大学生国际素养的价值意蕴是基础,围绕大学生国际素养开展课程教学改革是关键,积极创设大学生国际素养培育环境是保障。

关键词：人类命运共同体大学生国际素养要素内涵价值意蕴教学改革培育环境

Optimal Energy-Efficient Operation of a Metro Train on a Long and Steep Downhill Segment

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CSEE Journal of Power and Energy Systems 2023年第6期9卷 2356-2365页

作者： Deqiang He Hanqing jian Yanjun Chen jian miao Zhixiao Luo Chonghui Ren Lang Zhang the department of State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures Guangxi Key Laboratory of Manufacturing System&Advanced Manufacturing TechnologySchool of Mechanical EngineeringGuangxi UniversityNanning 530004China the department of Guangxi Police College Nanning 530028China. the department of Nanning Rail Transit Co. Ltd.Nanning 530029China

Because the standard four-stage operation and con-trol strategy cannot fully utilize the gravitational potential energy of a train operating on a long and steep downhill segment,this paper further improves the method for train operation and control *** improved operation includes three stages of acceleration,coasting-speed limit cruising,and *** the speed limit,time limit,and distance limit as the constraints,the coasting condition switching point,braking condition switching point,traction coefficient,and braking force coefficient are used as the decision ***,an improved train traction energy consumption model is constructed,and an improved differential evolution algorithm is designed to solve this *** improved method is used to simulate two long and steep downhill segments of the Nanning *** results show that the improved method can meet the requirements of speed limit,time limit,and distance *** with the standard four-stage operation,the improved train operation and control strategy can reduce train energy consumption by more than 40%on the two long and steep downhill segments;compared with other similar algorithms,the improved algorithm is more suitable for solving the model.

关键词： Energy-efficient operation improved differential evolution algorithm long and steep downhill segment metro train

Increased CAP37 Expression in Stable Chronic Obstructive Pulmonary Disease

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Current Medical Science 2022年第5期42卷 949-957页

作者： Jin-qing CHEN Yi-fei DUAN jian-miao WANG Department of Respiratory and Critical Care Medicine Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

Objective Cationic antimicrobial protein of 37 kDa(CAP37),a neutrophil-derived protein originally identified for its antimicrobial activity,is now known to have many regulatory effects on host ***,its role in the pathogenesis of chronic obstructive pulmonary disease(COPD)has not been *** therefore investigated the expression of CAP37 in COPD and its effects on airway structural cells,including bronchial epithelial cells,smooth muscle cells,and *** CAP37 was detected in the lung tissue,sputum,and plasma of COPD patients and the control subjects,as well as in the neutrophils stimulated by cigarette smoke extract(CSE).BEAS-2B cells,human bronchial smooth muscle cells(HBSMCs),and MRC-5 cells were treated with CAP37 or an anti-CAP37 antibody plus ***(IL)-6 and IL-8 were detected in the BEAS-2B *** cell proliferation was analyzed in the *** were also detected in the MRC-5 *** The expression of CAP37 was increased in the lung tissue and sputum supernatant of the COPD patients compared with the control *** sputum supernatant CAP37 levels were inversely correlated with the forced expiratory volume in the first second percentage predicted in ***37 was induced by CSE stimulation in the peripheral blood neutrophils from healthy ***37 induced expression of IL-6 and IL-8 in BEAS-2B cells,and collagen expression of lung fibroblasts(MRC-5 cells).However,CAP37 did not significantly alter the proliferation of the *** Our findings indicated that neutrophil-derived CAP37 may be involved in airway inflammation and fibrosis in COPD via affecting the bronchial epithelial cells,and fibroblasts,thus suggesting a possible role of CAP37 in the development and progression of COPD.

关键词： cationic antimicrobial protein of 37 kDa chronic obstructive pulmonary disease fibrosis inflammation neutrophil

超声引导下右侧星状神经节阻滞与右侧膈神经阻滞对妇科腹腔镜手术后肩痛的影响

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当代医学 2024年第12期30卷 22-27页

作者：毕生龙钟宗仁刘荣陈艾琼繆剑赣州市妇幼保健院麻醉科江西赣州341000

目的探究超声引导下右侧星状神经节阻滞(R-SGB)与右侧膈神经阻滞(R-PNB)治疗妇科腹腔镜手术后肩痛的效果。方法选取2022年2月至2023年2月于赣州市妇幼保健院行妇科腹腔镜手术的60例患者作为研究对象,随机分为对照组、实验1组与实验2组,... 详细信息

目的探究超声引导下右侧星状神经节阻滞(R-SGB)与右侧膈神经阻滞(R-PNB)治疗妇科腹腔镜手术后肩痛的效果。方法选取2022年2月至2023年2月于赣州市妇幼保健院行妇科腹腔镜手术的60例患者作为研究对象,随机分为对照组、实验1组与实验2组,每组20例。对照组给予右美托咪啶(DEX)治疗,实验1组给予DEX联合R-PNB治疗,实验2组给予DEX联合R-SGB治疗。比较3组血流动力学指标、血清炎症因子水平、肩部视觉模拟评分法(VAS)评分、Ramsey镇静评分、舒适评分、止痛药用量及不良反应发生情况。结果气管插管即刻(T2)、气腹后5min(T3)时,实验1组和实验2组HR均慢于对照组,T3时,实验1组MAP低于对照组,差异有统计学意义(P<0.05);3组其他时间MAP、HR两两比较差异无统计学意义。术后12h(T7)时,实验1组和实验2组TNF-α、IL-6水平均低于对照组,差异有统计学意义(P<0.05),实验1组与实验2组TNF-α、IL-6水平比较差异无统计学意义。术后1h(T5)~术后48h(T9)时,实验1组和实验2组VAS评分均低于对照组,Ramsey镇静评分均高于对照组,差异有统计学意义(P<0.05),实验1组与实验2组VAS和Ramsey镇静评分比较差异无统计学意义。实验1组和实验2组舒适评分均高于对照组,止痛药用量均少于对照组,差异有统计学意(P<0.05),实验1组与实验2组舒适评分和止痛药用量比较差异无统计学意义。3组不良反应发生率比较差异无统计学意义。结论超声引导下R-SGB和R-PNB治疗妇科腹腔镜手术后肩痛中均能有效改善患者术后疼痛,疗效较好。

关键词：右侧星状神经节阻滞右侧膈神经阻滞妇科腹腔镜手术肩痛