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Frontiers of Mechanical Engineering 2021年第3期16卷 570-579页

作者： Song YUAN Xiaoguang GUO Penghui LI shuohua zhang Ming LI Zhuji JIN Renke KANG Dongming GUO Fumin LIU Lemin zhang Key Laboratory for Precision and Non-Traditional Machining Technology of Ministry of Education Dalian University of TechnologyDalian 116024China Beijing Institute of Aerospace Control Device Beijing 100854China

The interfacial wear between silicon and amorphous silica in water environment is critical in numerous ***,the understanding regarding the micro dynamic process is still unclear due to the limitations of ***,reactive force field simulations are utilized to study the interfacial process between silicon and amorphous silica in water environment,exploring the removal and damage mechanism caused by pressure,velocity,and ***,the reasons for high removal rate under high pressure and high velocity are elucidated from an atomic *** results show that the substrate is highly passivated under high humidity,and the passivation layer could alleviate the contact between the abrasive and the substrate,thus reducing the damage and *** addition to more Si-O-Si bridge bonds formed between the abrasive and the substrate,new removal pathways such as multibridge bonds and chain removal appear under high pressure,which cause higher removal rate and severer *** a higher velocity,the abrasive can induce extended tribochemical reactions and form more interfacial Si-O-Si bridge bonds,hence increasing removal *** results reveal the internal cause of the discrepancy in damage and removal rate under different conditions from an atomic level.

关键词： silicon ReaxFF molecular dynamics friction damage

基于对抗训练与Transformer的风力发电机故障分类方法

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计算机工程 2024年第9期50卷 377-384页

作者：王言国吕鹏远兰金江刘明哲秦冠军张硕桦周宇南瑞继保工程技术有限公司江苏南京211106 中国三峡新能源(集团)股份有限公司北京101100 南京航空航天大学计算机科学与技术学院/人工智能学院江苏南京211106

风力发电机故障分类的复杂性和多样性严重影响风能发电效率,传统的人工方法效率低下,准确率较低,已有的深度学习模型在真实环境中易受数据噪声干扰而表现不佳。为提升风力发电机故障分类模型在真实环境下的分类性能与鲁棒性,提出一种基... 详细信息

风力发电机故障分类的复杂性和多样性严重影响风能发电效率,传统的人工方法效率低下,准确率较低,已有的深度学习模型在真实环境中易受数据噪声干扰而表现不佳。为提升风力发电机故障分类模型在真实环境下的分类性能与鲁棒性,提出一种基于对抗训练与Transformer的故障分类方法。首先通过引入一维卷积与门控线性单元(GLU)增强注意力机制对局部特征的学习,保留易被忽略的局部信息,提升模型对于局部特征的敏感度。其次结合限制因子约束对抗样本,提高对抗样本产生的准确性。最后在消除错误样本的同时反馈生成过程,使其具备更好的抗干扰能力。实验结果表明,与5种常用的分类模型相比,所提模型分类性能平均提升7.76%,与真实结果之间的误差最小。局部增强的注意力机制和所提的对抗训练方法分别使模型的分类性能平均提升4.51%、4.95%。所提模型在10%~20%噪声环境中仍保持较好性能,增强了其在真实环境中的稳定性。该方法在提高分类准确率的同时使模型具备更强的泛化能力,对于提升风力发电机故障分类性能与鲁棒性具有重要意义。

关键词：风力发电机门控线性单元 Transformer模型对抗训练故障分类

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轮轨耦合高速电梯导轨振动特性分析

山东建筑大学学报 2018年第1期33卷 18-24,58页

作者：张青杨玉虎仉硕华张瑞军天津大学机械工程学院天津300072 山东建筑大学机电工程学院山东济南250101

电梯的不断提速使得导轨的振动越来越明显,降低了高速电梯运行的舒适性和安全性。因此,对在高速状态下电梯导轨振动响应的研究势在必行。文章基于达朗贝尔原理,从轮轨及滚轮与轿厢间的相互作用关系出发,建立了轿厢—滚轮—导轨大系统的... 详细信息

电梯的不断提速使得导轨的振动越来越明显,降低了高速电梯运行的舒适性和安全性。因此,对在高速状态下电梯导轨振动响应的研究势在必行。文章基于达朗贝尔原理,从轮轨及滚轮与轿厢间的相互作用关系出发,建立了轿厢—滚轮—导轨大系统的耦合动力学模型;采用变量离散下的新型显式二步数值积分法,借助MATLAB软件进行数值仿真,研究了各结构参数对导轨振动的影响规律。结果表明:高速电梯轿厢系统与导轨耦合作用下,导轨的水平振动响应不可忽略且表现出振动挠度和震荡2种形式;导轨表面不平度主要影响导轨震荡,且幅值随其表面不平度增大而增大;轮轨预紧力对导轨振动挠度和震荡均有显著影响,当预紧力取值分别为10、20、40 N时,导轨振动挠度幅值分别为1.9×10^(-5)、3.4×10^(-5)、6.8×10^(-5)m,其振动挠度近似成倍增加,同时导轨的震荡幅值则逐渐减小。

关键词：高速电梯轮轨耦合导轨振动接触参数

钢结构梁柱半刚性节点连接3种设计方案及其对比

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中国电梯 2018年第1期29卷 7-10,62页

作者：刘立新仉硕华张青孙华跃张瑞军山东富士制御电梯有限公司山东德州253000 山东建筑大学机电工程学院济南250101

设计了3种钢结构梁柱半刚性节点连接结构方案,采用ANSYS Workbench软件对这3种结构进行力学分析,并通过对比分析给出3种结构在受力、安装及美观度等方面的适用性。

关键词：钢结构梁柱半刚性节点连接结构形式仿真适用性

4m／s高速电梯振动噪声分析及减振降噪方案

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中国电梯 2017年第21期28卷 9-11,21页

作者：刘立新张青滕法元仉硕华张瑞军山东富士制御电梯有限公司山东德州253000 山东建筑大学机电工程学院济南250101

运用振动检测和噪声识别技术，对一台曳引比为2：1、额定速度为4m／s的高速电梯运行过程中的振动和噪声原因进行了分析。根据分析结果，逐条提出了减振降噪的具体解决方案。方案实施后，经检测证明减振降噪效果明显。

关键词：高速电梯振动噪声减振降噪

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基于Blender的工业三维动画制作研究

机械工程师 2023年第2期 98-101页

作者：张朔华王兰兰福全戴嘉庆周忠祥张茄新中油国家油气钻井装备工程技术研究中心有限公司陕西宝鸡721002 宝鸡石油机械有限责任公司陕西宝鸡721002 西部钻探工程有限公司准东钻井公司新疆克拉玛依834009

工业三维动画是以产品展示为目的的计算机图形技术应用。随着技术的不断发展,三维动画制作工具与技术不断更新迭代。Blender是近年来流行的开源三维动画制作软件,以高效渲染和流程集成化著称,有逐渐成为三维动画主流制作软件的趋势。文... 详细信息

工业三维动画是以产品展示为目的的计算机图形技术应用。随着技术的不断发展,三维动画制作工具与技术不断更新迭代。Blender是近年来流行的开源三维动画制作软件,以高效渲染和流程集成化著称,有逐渐成为三维动画主流制作软件的趋势。文中介绍了一种基于Blender的工业三维动画制作流程,并对制作过程中的部分实用功能进行介绍。

关键词：工业三维动画 Blender 计算机图形技术应用

Associations between blood glucose and early- and late-onset colorectal cancer: evidence from two prospective cohorts and Mendelian randomization analyses

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Journal of the National Cancer Center

Journal of the National Cancer Center 2024年第3期4卷 241-248页

作者： Chenyu Luo Jiahui Luo Yuhan zhang Bin Lu Na Li Yueyang Zhou shuohua Chen Shouling Wu Qingsong zhang Min Dai Hongda Chen Department of Cancer Epidemiology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Center for Prevention and Early Intervention National Infrastructures for Translational MedicineInstitute of Clinical MedicinePeking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Cardiology Department Kailuan General HospitalTangshanChina Department of General Surgery Kailuan General HospitalTangshanChina

Background: The incidence of early-onset colorectal cancer (EOCRC), which exhibits differential clinical, patho- logical, and molecular features compared to late-onset CRC (LOCRC), is rising globally. The potential differential effects of blood glucose on EOCRC compared to LOCRC have not been investigated. Methods: This study analyzed 374,568 participants from the UK Biobank cohort and 172,809 participants from the Kailuan cohort. The linear associations between blood glucose and EOCRC/LOCRC were estimated using Cox regression models. Restricted cubic spline (RCS) analysis and non-linear Mendelian randomization (MR) analysis using a 70-SNPs genetic instrument for fasting glucose were used to explore the potential non-linear associations. Results: Participants in the highest quintile of blood glucose had higher overall CRC risk compared to the lowest quintile (HR = 1.10 in the UK Biobank cohort, 95% CI: 1.01-1.21, P -trend = 0.012;HR = 1.23 in the Kailuan cohort, 95% CI: 1.01-1.51, P -trend = 0.036). Elevated glucose ( > 7.0 mmol/L) was more strongly associated with increased risk of EOCRC (HR = 1.61, 95% CI: 1.07-2.44) than with LOCRC (HR = 1.14, 95% CI: 1.02-1.27) in the UK Biobank cohort ( P- heterogeneity = 0.014). Elevated glucose ( > 7.0 mmol/L) was associated with increased risk of LOCRC (HR = 1.25, 95% CI: 1.04-1.65) in the Kailuan cohort as well. There was no evidence for non-linear associations between blood glucose and risks of EOCRC/LOCRC. Conclusions: This study showed a positive association between blood glucose and CRC risk in a dose-response manner, particularly for EOCRC, suggesting that tighter glucose control should be a priority for younger age groups.

关键词： Colorectal cancer Early-onset colorectal cancer Glucose Mendelian randomization Cancer prevention

Low Concordance Between Blood Pressures Measured in Periodic Health Examinations and in a Workplace-Based Hypertension Management Program

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Phenomics 2022年第6期2卷 419-429页

作者： Jun-Xiang Chen Yan-Feng Zhou Tingting Geng Simiao Chen shuohua Chen Guodong Wang Yan-Bo zhang Yi Wang Zhou-Zheng Tu Gang Liu Shouling Wu An Pan Department of Epidemiology and Biostatistics Ministry of Education Key Laboratory of Environment and HealthSchool of Public HealthTongji Medical CollegeHuazhong University of Science and Technology13 Hangkong RoadWuhan 430030HubeiChina Heidelberg Institute of Global Health Faculty of Medicine and University HospitalHeidelberg University44883 HeidelbergGermany Department of Cardiology Kailuan General HospitalNorth China University of Science and Technology57 Xinhua East RoadTangshan 063000HebeiChina Department of Nutrition and Food Hygiene Hubei Key Laboratory of Food Nutrition and SafetySchool of Public HealthTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430040HubeiChina

Poor adherence to standard protocols of blood pressure(BP)measurement in routine clinical practice leads to higher readings than“research-quality”*** this phenomenon exists in periodic health examinations was *** aimed to explore the concordance between BP measurements in periodic health examinations and those measured following a standard measurement *** used data from the Kailuan Study,an ongoing longitudinal cohort study in China,of which participants received biennial health examinations in health management *** addition,BPs were measured following standard protocols in a workplace-based hypertension management program nested in the Kailuan *** compared BP readings of the same person between the two settings using generalized linear mixed-effects models.A total of 3988 men(the mean age was 44.9 years)had at least two BP measurements both in health examinations and management program with a time interval between the two settings that less than 90 *** mean systolic blood pressures(SBP)and diastolic blood pressures(DBP)in health examinations were 4.2(95%CI 3.9–4.5)mm Hg and 3.3(95%CI 3.1–3.5)mm Hg higher than those in the management program,***–Altman analyses showed the wide agreement inter-vals ranging from-27.7-to 36.5-mm Hg for SBP and-18.3-to 24.7-mm Hg for *** conclusion,BP measurements in periodic health examinations were generally higher than BPs measured following a standard *** findings highlight the importance of standard BP measurement to avoid overestimation of hypertension prevalence and treatment initiation.

关键词： Hypertension Physical examination Blood pressure determination Guideline adherence

Composition and Functional Capacity of Gut Microbes are Associated with Arterial Stiffness:A Prospective Study

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Cardiology Discovery 2023年第2期3卷 102-111页

作者： Jing Li Yixuan Zhong Jingjing Bai shuohua Chen Jun Cai Shouling Wu Weili zhang Heart Center&Beijing Key Laboratory of Hypertension Beijing Chaoyang HospitalCapital Medical UniversityBeijing 100020China National Clinical Research Center of Cardiovascular Diseases State Key Laboratory of Cardiovascular DiseaseFuWai HospitalNational Center for Cardiovascular DiseasesPeking Union Medical College&Chinese Academy of Medical SciencesBeijing 100037China Department of Cardiology Kailuan General HospitalTangshanHebei 063000China Central-China Branch of National Center for Cardiovascular Diseases Henan Cardiovascular Disease CenterFuwai Central-China HospitalZhengzhou 450046China.

Objective:Arterial stiffness is an important predictor of cardiovascular *** diversity in the gut has been shown to be associated inversely with arterial stiffness in Caucasian ***,due to the different profiles of the gut microbiota among ethnicities,the relationship between gut-microbiota dysbiosis and the progression of arterial stiffness merits further *** study aimed to investigate the association between the composition and functional capacity of the gut microbiota and the progression of arterial ***:“Shotgun”metagenomics sequencing were undertaken in 96 individuals from a hypertension-associated gut-microbiota study in the Kailuan cohort,who measured brachial-ankle pulse wave velocity(baPWV)and provided fecal samples between September 2014 and February 2015 at Kailuan General Hospital and 11 affiliated *** different composition and functional capacity of the gut microbiota were compared between individuals without arterial stiffness(normal arterial stiffness group,baPWV<1,400 cm/s,n=27)and participants with arterial stiffness(increased arterial stiffness group,baPWV≥1,400 cm/s,n=69)at *** participants were followed up prospectively for a mean duration of 2.6 years,and 50 underwent a repeat baPWV *** between the gut microbiota and severity and progression of arterial stiffness were assessed using MaAsLin2 software after adjustment for age,sex,and mean arterial blood pressure and correction for multiple ***“catalogs”were aligned to the Kyoto Encyclopedia of Genes and Genomes(KEGG)database to obtain information for potential functional capacities of the gut ***:In this study,14 genera and 50 species of bacteria were identified to be abundant in participants with normal arterial stiffness compared with those with increased arterial *** 14 genera,the prevalence of beneficial bacteria of the genera Leadbetterella and Cytophaga was cor

关键词： Arterial stiffness Brachial-ankle pulse wave velocity Gut microbiota Microbial functions

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汽车悬挂系统显式模型预测控制

信息与控制 2009年第6期38卷 692-697页

作者：张聚刘江王槊华浙江工业大学信息工程学院浙江杭州310014

本文把显式模型预测控制应用于汽车悬架主动控制,以改善汽车悬架系统的控制效果,并满足系统状态性能和控制力等方面约束条件.针对汽车悬挂动力学简化模型(二维)和1/2悬挂动力学模型,并做了数值仿真计算.研究结果表明了汽车悬挂系统显式... 详细信息

本文把显式模型预测控制应用于汽车悬架主动控制,以改善汽车悬架系统的控制效果,并满足系统状态性能和控制力等方面约束条件.针对汽车悬挂动力学简化模型(二维)和1/2悬挂动力学模型,并做了数值仿真计算.研究结果表明了汽车悬挂系统显式模型预测控制系统的有效性.

关键词：多参数二次规划显式模型预测控制主动悬架