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Friction 2024年第2期12卷 271-290页

作者： shaohua li Xiaohui liN Shuyun JIANG School of Mechanical Engineering Southeast UniversityNanjing 211189China

Bubbly oil lubrication is a type of lubrication ***,the lubrication model of the bubbly oil has not been thoroughly *** paper aims to investigate the modelling for bubbly oil lubrication considering the interfacial effect and thermal effect,and a theoretical model is established based on the theory of multiphase *** interfacial and thermal effects on the static characteristics of a thrust bearing are analyzed.A test rig for the thrust bearing is developed to measure the static characteristics of the bearing under bubbly oil *** results show that the bearing static characteristics,*** temperature rise,film thickness,friction torque,and volume flow,increase with consideration of three interfacial effects;the bearing temperature rise increases but the film thickness,friction torque,and volume flow rate decrease with consideration of the three thermal effects;the thermal effect on the bearing static characteristics is greater than the interfacial effect.

关键词： bubbly oil lubrication theory of multiphase mixtures interfacial effect thermal effect fluid bearing

Integrated Active Suspension and Anti-Lock Braking Control for Four-Wheel-Independent-Drive Electric Vehicles

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 87-98页

作者： Ze Zhao Lei Zhang Xiaoling Ding Zhiqiang Zhang shaohua li liang Gu National Engineering Research Center for Electric Vehicles Beijing Institute of TechnologyBeijing 100081China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang 050043China

This paper presents an integrated control scheme for enhancing the ride comfort and handling performance of a four-wheel-independent-drive electric vehicle through the coordination of active suspension system(ASS)and anti-lock braking system(ABS).First,a longitudinal-vertical coupled vehicle dynamics model is established by integrating a road input *** the coupling mechanisms between longitudinal and vertical vehicle dynamics are *** ASS-ABS integrated control system is proposed,utilizing an H∞controller for ASS to optimize load transfer effect and a neural network sliding mode control for ABS ***,the effectiveness of the proposed control scheme is evaluated through comprehensive tests conducted on a hardware-in-loop(HIL)test *** HIL test results demonstrate that the proposed control scheme can significantly improve the braking performance and ride comfort compared to conventional ABS control methods.

关键词： Four-wheel-independent-drive electric vehicles Active suspension system(ASS) Anti-lock braking system(ABS) Vertical-longitudinal vehicle dynamics

Braille Character Segmentation Algorithm Based on Gaussian Diffusion

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Computers, Materials & Continua 2024年第4期79卷 1481-1496页

作者： Zezheng Meng Zefeng Cai Jie Feng Hanjie Ma Haixiang Zhang shaohua li School of Computer Science and Technology Zhejiang Sci-Tech UniversityHangzhou310018China

Optical braille recognition methods typically employ existing target detection models or segmentation modelsfor the direct detection and recognition of braille characters in original braille images. However, these methodsneed improvement in accuracy and generalizability, especially in densely dotted braille image environments. Thispaper presents a two-stage braille recognition framework. The first stage is a braille dot detection algorithmbased on Gaussian diffusion, targeting Gaussian heatmaps generated by the convex dots in braille images. Thisis applied to the detection of convex dots in double-sided braille, achieving high accuracy in determining thecentral coordinates of the braille convex dots. The second stage involves constructing a braille grid using traditionalpost-processing algorithms to recognize braille character information. Experimental results demonstrate that thisframework exhibits strong robustness and effectiveness in detecting braille dots and recognizing braille charactersin complex double-sided braille image datasets. The framework achieved an F1 score of 99.89% for Braille dotdetection and 99.78% for Braille character recognition. Compared to the highest accuracy in existing methods,these represent improvements of 0.08% and 0.02%, respectively.

关键词： Computer vision image recognition optical braille recognition

Effect of deformation parameters on the austenite dynamic recrystallization behavior of a eutectoid pearlite rail steel

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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 833-841页

作者： Haibo Feng shaohua li Kexiao Wang Junheng Gao Shuize Wang Haitao Zhao Zhenyu Han Yong Deng Yuhe Huang Xinping Ma Institute for Carbon Neutrality University of Science and Technology BeijingBeijing 100083China Institute for Steel Sustainable Technology Liaoning Academy of MaterialsShenyang 110004China Pangang Group Panzhihua Iron and Steel Research Institute Co.Ltd. Panzhihua 617000China

Understandings of the effect of hot deformation parameters close to the practical production line on grain refinement are crucial for enhancing both the strength and toughness of future rail *** this work,the austenite dynamic recrystallization(DRX)behaviors of a eutectoid pearlite rail steel were studied using a thermo-mechanical simulator with hot deformation parameters frequently employed in rail production *** single-pass hot deformation results reveal that the prior austenite grain sizes(PAGSs)for samples with different deformation reductions decrease initially with an increase in deformation ***,once the deformation temperature is beyond a certain threshold,the PAGSs start to *** can be attributed to the rise in DRX volume fraction and the increase of DRX grain with deformation temperature,***-pass hot deformation results show that the accumulated strain generated in the first and second deformation passes can increase the extent of *** the case of complete DRX,PAGS is predominantly determined by the deformation temperature of the final *** suggests a strategic approach during industrial production where part of the deformation reduction in low temperature range can be shifted to the medium temperature range to release rolling mill loads.

关键词： eutectoid pearlite rail steel prior austenite grain size dynamic recrystallization single-pass hot deformation three-pass hot deformation

Analysis of the Current Situation and Influencing Factors of Physical Activity Among the Elderly in the Community

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Journal of Clinical and Nursing Research 2024年第6期8卷 345-350页

作者： Wei Dong Jialiang Wang Dongmei Cui Yanling li shaohua li Zheng li Physical Examination Center Affiliated Hospital of Hebei UniversityBaoding 071000Hebei ProvinceChina Department of Neurosurgery Affiliated Hospital of Hebei UniversityBaoding 071000Hebei ProvinceChina Department of Nursing Affiliated Hospital of Hebei UniversityBaoding 071000Hebei ProvinceChina Department of Neonatology Affiliated Hospital of Hebei UniversityBaoding 071000Hebei ProvinceChina Department of Nephrology Affiliated Hospital of Hebei UniversityBaoding 071000Hebei ProvinceChina

Objective:To explore the current situation of physical activity among elderly individuals in the community,identify influencing factors,and provide a theoretical basis for improving their physical activity levels in the ***:A questionnaire survey was conducted among 265 elderly community residents using the Physical Activity Scale for the ***:The median(p50)score on the Physical Activity Scale for the Elderly was 220.425,indicating a high level of physical *** was no statistically significant difference in physical activity levels between ***:Elderly individuals should be supported in actively and scientifically participating in physical activities to mitigate physical function decline and achieve successful aging.

关键词： Community Elderly Physical activity

Analysis of the Current Situation and Influencing Factors of Social Isolation Among the Elderly in the Community

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Proceedings of Anticancer Research 2024年第3期8卷 150-156页

作者： Weiwei Dong Xiaohui Qi Jialiang Wang Dongmei Cui Yanling li shaohua li Physical Examination Center Affiliated Hospital of Hebei UniversityBaoding 071000Hebei ProvinceChina Departement of Respiratory and Critical Care Medicine Affiliated Hospital of Hebei UniversityBaoding 071000Hebei ProvinceChina Department of Neurosurgery Affiliated Hospital of Hebei UniversityBaoding 071000Hebei ProvinceChina Departement of Nursing Affiliated Hospital of Hebei UniversityBaoding 071000Hebei ProvinceChina Departement of Neonatology Affiliated Hospital of Hebei UniversityBaoding 071000Hebei ProvinceChina

Objective: To investigate the current situation of social isolation among the elderly in the community, and to analyze its influencing factors. Methods: A total of 265 elderly people were selected to conduct the survey using the general information questionnaire and the Chinese version of the social isolation scale for the elderly. Results: The social isolation score of the elderly was (20.15 ± 0.23). Factors such as age, education level, economic status, and social participation ability influenced the social isolation score (P < 0.05). Conclusion: The social isolation of the elderly is more serious, and the social isolation can be alleviated by improving the level of education and the economic situation and strengthening social participation.

关键词： Community Elderly Social isolation

从上博简《采风曲目》看《诗经·国风》以声别类

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音乐研究 2024年第2期 13-16,I0009,I0010,17-22页

作者：李韶华东北师范大学历史文化学院

《诗经》是周代仪式乐歌的文本集合,其分类及其标准素有争议,且多集中于《风》《雅》《颂》一级分类和十五《国风》二《雅》三《颂》二级分类的探讨,较少瞩目三级分类,尤其是占《诗经》半数的《国风》每一部别的分类及其标准。上博简《... 详细信息

《诗经》是周代仪式乐歌的文本集合,其分类及其标准素有争议,且多集中于《风》《雅》《颂》一级分类和十五《国风》二《雅》三《颂》二级分类的探讨,较少瞩目三级分类,尤其是占《诗经》半数的《国风》每一部别的分类及其标准。上博简《采风曲目》以排布规律的专有音乐术语来分类颇具风诗特点的楚地民歌,反映了乐官采风后会对风诗以声别类予以编排,为《诗经》文本结构中没有呈现的《国风》三级分类及其标准提供了重要线索,表明《诗经》三级分类形态下的每一子目皆是以音乐区分的结果。不仅如此,结合传世文献和出土文献记载的楚国乐律体系来看,《采风曲目》中“宫穆”“徽和”等标音称谓不是变化音名而是调名,这些调名与弦类乐器的调弦法密切相关,揭示了风诗以调分类这一具体乐学含义。

关键词：《采风曲目》《诗经》《国风》分类诗以声别调

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清华简《周公之琴舞》文本结构及其乐舞体制

古代文明（中英文） 2024年第2期18卷 49-60,M0004页

作者：李韶华东北师范大学历史文化学院吉林长春130024

清华简《周公之琴舞》是由篇题、序言以及含有乐诗演奏符号在内的十首歌辞组成的诗文本,是周代乐官掌教的典礼乐舞演奏脚本。篇题中的“琴舞”表明这部乐舞以琴为伴奏乐器的同时又以琴为舞具,序言两次出现的“九絉”表明这部乐舞使用的... 详细信息

清华简《周公之琴舞》是由篇题、序言以及含有乐诗演奏符号在内的十首歌辞组成的诗文本,是周代乐官掌教的典礼乐舞演奏脚本。篇题中的“琴舞”表明这部乐舞以琴为伴奏乐器的同时又以琴为舞具,序言两次出现的“九絉”表明这部乐舞使用的是在上古九体乐舞基础上根据典礼需要改编而成的“1+9”结构的新式乐舞结构,与歌辞融为一体的“启”“乱”等演奏符号在标识乐舞开幕的同时,也表明每一幕乐舞的伴奏乐歌皆由演唱形式不同的两部分构成。简文这种在结构内容上体现出的重视礼乐实践指导而不同于传世本《诗经》的文本样态,是周代乐官对仪式乐歌用于教习、演奏时相关信息的文字记载,是乐家传《诗》的一种。

关键词：《周公之琴舞》琴舞九絉启乱乐家《诗》

参数冻结精细指数积分法在非线性车桥耦合振动分析中的应用

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力学学报 2024年第1期56卷 258-272页

作者：张宇李韶华任剑莹石家庄铁道大学省部共建交通工程结构力学行为与系统安全国家重点实验室石家庄050043 石家庄铁道大学工程力学系石家庄050043 石家庄铁道大学河北省工程力学基础学科研究中心石家庄050043

描述车桥耦合作用的基本问题是一个时变系统问题,且很多工况下需考虑非线性特性,使得该问题难以得到解析解,甚至数值解也可能很复杂.针对该问题的求解,提出了一种参数冻结精细指数积分法,将其应用于车桥耦合动力学模型的数值分析中.该... 详细信息

描述车桥耦合作用的基本问题是一个时变系统问题,且很多工况下需考虑非线性特性,使得该问题难以得到解析解,甚至数值解也可能很复杂.针对该问题的求解,提出了一种参数冻结精细指数积分法,将其应用于车桥耦合动力学模型的数值分析中.该方法结合了精细积分和指数积分特点,并将时变系数矩阵在每一积分步参数冻结,用于获得系统振动响应的数值解.考虑汽车轮胎与桥面的力和位移耦合关系、桥面沥青铺装层、桥梁材料黏弹性和几何非线性特性,建立了车桥耦合动力学模型,并应用参数冻结精细指数积分法对该模型进行了求解.通过与近似解析解、辛Runge-Kutta算法以及经典的Newmark-β数值积分法计算结果进行对比,验证了所提出方法计算结果的有效性和准确性.在此基础上,制作了缩尺车桥耦合系统模型,测试了跨中挠度响应,进一步验证了理论建模和所提算法的有效性和实用性.通过数值计算分析了所提算法的数值特性,结果表明:提出的参数冻结精细指数积分法不仅可以处理时变、非线性问题,且具有良好的数值计算精度和长时间数值稳定性;由于精细积分的特点,参数冻结精细指数积分法的计算时间步长可以取的较大,可有效提高计算效率.因此,所提出的参数冻结精细指数积分法预期可成为求解车桥耦合动力学问题的一种新的高效算法.

关键词：精细指数积分法车桥耦合振动参数冻结非线性时变系统辛Runge-Kutta算法

基于分数阶的空气弹簧建模及电动汽车主动悬架控制研究

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汽车工程 2024年第7期46卷 1282-1293,1301页

作者：冯桂珍赵东鹏李韶华石家庄铁道大学省部共建交通工程结构力学行为与系统安全国家重点实验室石家庄050043 石家庄铁道大学机械工程学院石家庄050043

电控空气悬架系统(electrically controlled air suspension, ECAS)具有调节悬架刚度和车身高度的功能,可有效改善车辆乘坐舒适性和操纵稳定性。以某乘用车ECAS为对象,利用分数阶理论描述橡胶气囊的黏弹性阻尼特性,考虑等效阻尼及滞回... 详细信息

电控空气悬架系统(electrically controlled air suspension, ECAS)具有调节悬架刚度和车身高度的功能,可有效改善车辆乘坐舒适性和操纵稳定性。以某乘用车ECAS为对象,利用分数阶理论描述橡胶气囊的黏弹性阻尼特性,考虑等效阻尼及滞回特性对其热力学模型进行了优化,结果与实验数据吻合良好,验证了优化后的空气弹簧模型的精确性。在此基础上,考虑车辆纵横向动力学特性与Dugoff轮胎模型,建立14自由度整车ECAS动力学模型,提出模型预测(model predictive control, MPC)主动悬架控制方法,以可测变量为控制器输入,实现直线及转向行驶工况下的主动控制。仿真与整车台架实验研究表明,分数阶修正模型可以很好地反映ECAS变刚度特性,基于MPC的主动悬架控制策略能实时调整空气弹簧刚度,控制车身姿态,有效改善电动汽车行驶时的平顺性与稳定性。论文的研究方法为车辆悬架系统建模及主动控制提供了一种新思路。

关键词：空气悬架热力学黏弹性阻尼分数阶模型预测控制