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CALCULATION OF ELASTIC DAMPING CHARACTERISTICS OF ROTOR SUPPORT MADE OF METAL RUBBER MATERIAL UNDER VARIABLE LOADS

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Chinese Journal of Mechanical Engineering 2007年第6期20卷 33-37页

作者： JIANG Hongyuan YAN Hui ao hongrui ALEXANDER M Ulanov School of Mechatronics Engineering Harbin Institute of Technology Harbin 150001 China Department of Aircraft and Engine Structure Design Samara State Aerospace University Samara 443086 Russia

A metal rubber（MR） dry friction damper was designed based on the load supported by the rotor. An experimental apparatus for obtaining hysteresis loops of support under the precession load was designed. The elastic-damping characteristics of the ring-shaped MR damper used as a rotor support under variable loads were presented by studying the hysteresis loops of the damper. The vibration rigidity and the energy dissipation coefficient were calculated from the hysteresis loops, based on the description of the deformation process of the MR element with simple structure in a dimensionless coordinating system. The calculation results showed that the energy dissipation coefficient in the inner of MR element and on the boundary between the damper and the frame of the rotor support were approximately equal. The comparison of the hysteresis loops for a precession load and a one-axial load indicated a large difference when the coefficient of the energy dissipation and the stiffness of the MR damper were concerned.

关键词： Rotor support Precession load Stiffness Energy dissipation coefficient Metal rubber

Influence of Disk Surface Bulge and Hard Disk Operating Conditions on Hard Disk Gas Film Heat Transfer

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Journal of Harbin Institute of Technology(New Series) 2021年第1期28卷 20-29页

作者： Qinyang Zeng hongrui ao Hongyuan Jiang School of Mechatronics Engineering Harbin Institute of TechnologyHarbin 150001China

When the hard disk is running,the cantilever of the magnetic head imposes a certain preload on the slider of the magnetic head to form a wedge space with the *** the disk rotates,the viscous gas enters the convergence gap so that the hydrodynamic pressure generates balance with the force acting on the cantilever,ensuring that the magnetic head flies above the disk in a stable altitude and forms a stable air film between the magnetic head and the disk called air *** the flight altitude is low,the bulge on the disk surface will affect the pressure distribution of air ***,the pressure affects the heat flux of air bearing by influencing the heat transfer parameters,such as thermal conductivity,dynamic viscosity,gas density,and the molecular free path of the *** this paper,heat transfer parameters influence on gas film heat transfer were *** on this,flathead slider and Tri-pad barotropic magnetic head slider were compared,and the effects of disk operating conditions at the average temperature of air bearing were also studied,such as pitch and roll angle of the magnetic head slider,the disk s speed,and the bulge on disk surface.

关键词： air bearing heat transfer Tri-pad barotropic head slider

Study on Lubricant Materials Transfer between Head and Disk

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Journal of Harbin Institute of Technology(New Series) 2020年第6期27卷 17-26页

作者： Qinyang Zeng hongrui ao Hongyuan Jiang School of Mechatronics Engineering Harbin Institute of TechnologyHarbin 150001China

With the increase of hard disk storage density,the flying height of magnetic head sliders has become lower in recent years,which makes it easier for lubricant materials to transfer between the magnetic head and *** ability for lubricant materials to transfer is not only related to the operating conditions of disk but also related to the types of lubricant materials(Perfluoropolyether,PFPE)and diamond⁃like carbon(DLC)coating applied to the *** on the principle of molecular dynamics,this study established the adsorption models on disks with different carbon content and the diffusion models of several common PFPE molecules in ***,the adsorption energy and the diffusion coefficients of different models were ***,the molecular weight,the molecular structure,the lubricant material􀆳s end functional groups,and the disk􀆳s carbon content were found to have influence on the transfer ability of lubricant *** particular,the latter two factors have further influence.

关键词： molecular dynamics adsorption energy diffusion coefficient

圆柱形金属橡胶多孔材料流体动压性能相似性判据的确定

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机械工程学报 2005年第6期41卷 50-54页

作者：夏宇宏姜洪源敖宏瑞闫辉 Белоусов А И 哈尔滨工业大学机电工程学院哈尔滨150001 俄罗斯萨玛拉国立航空航天大学俄罗斯443086

依据金属橡胶多孔材料的制备工艺及节流特性,确定了影响金属橡胶节流元件流体动压特性的影响参数。利用相似性定理中的量纲相似理论(π定理),推导出了决定圆柱形金属橡胶多孔材料流体动压特性的7个相似性判据,为试验研究及结果分析提供... 详细信息

依据金属橡胶多孔材料的制备工艺及节流特性,确定了影响金属橡胶节流元件流体动压特性的影响参数。利用相似性定理中的量纲相似理论(π定理),推导出了决定圆柱形金属橡胶多孔材料流体动压特性的7个相似性判据,为试验研究及结果分析提供了依据,极大地减少了试验工作量和试验及分析工作的盲目性。该论文的研究成果对于研究多孔材料具有非常重要的参考价值。

关键词：金属橡胶多孔材料相似性判据流体动压特性

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基于三电层模型的交流电渗流速分析

机械工程学报 2011年第24期47卷 135-140页

作者：李姗姗敖宏瑞侯珍秀姜洪源哈尔滨工业大学机电工程学院哈尔滨150001

微通道内交流电渗微泵的流速与电极表面双电层的结构与电荷分布密切相关,根据传统双电层理论和交流电渗速度公式可以预测交流电渗流速分布和速度峰值处的转折频率。试验发现,由此得出的交流电渗流速峰值比试验值大数倍。考虑紧密层和中... 详细信息

微通道内交流电渗微泵的流速与电极表面双电层的结构与电荷分布密切相关,根据传统双电层理论和交流电渗速度公式可以预测交流电渗流速分布和速度峰值处的转折频率。试验发现,由此得出的交流电渗流速峰值比试验值大数倍。考虑紧密层和中间层厚度对交流电渗流的影响,提出三电层模型,给出三电层等效厚度和等效相对介电常数的求解方法,对传统的交流电渗速度公式进行修正,得出修正后的时间平均流速、位置平均流速和转折频率表达式。以宽度和间距均为20?m的平行电极阵列为试验对象,对其施加相位差90°的四相行波电场,用电荷耦合元件(Charge-coupled device,CCD)记录流场中荧光粒子的轨迹并用micro-PIV方法计算流场速度。设置不同的电层厚度参数对试验进行仿真。结果表明,紧密层厚度为几个溶剂分子大小(0.5 nm),而且中间层厚度为电极表面微观起伏高度(5 nm)时,仿真和试验结果非常接近,这表明三电层模型和修正后流速公式的有效性。

关键词：交流电渗三电层流速公式修正电极表面粗糙度

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深腔圆锥动静压混合轴承润滑特性

哈尔滨工业大学学报 2013年第1期45卷 60-66页

作者：李胜波敖宏瑞姜洪源陈亮 KORNEEV A. 哈尔滨工业大学机电工程学院哈尔滨150001 黑龙江科技学院机械学院哈尔滨150027 俄罗斯奥廖尔国立技术大学产品新技术及自动化系奥廖尔俄罗斯302020

为了更加准确探求深腔圆锥动静压轴承润滑特性,考虑润滑油膜紊流、热效应及轴向速度等因素,推导极坐标系下的广义雷诺方程、能量控制方程及其相关表达式,采用有限差分法对方程进行离散,利用帕坦卡正系数法则对离散化方程系数及常数项进... 详细信息

为了更加准确探求深腔圆锥动静压轴承润滑特性,考虑润滑油膜紊流、热效应及轴向速度等因素,推导极坐标系下的广义雷诺方程、能量控制方程及其相关表达式,采用有限差分法对方程进行离散,利用帕坦卡正系数法则对离散化方程系数及常数项进行处理,数值分析油膜的三维压力场和温度场,试验研究静压浮起和动压润滑特性.结果表明:帕坦卡正系数法则可以有效地解决诸如油腔边缘存在"逆流"等因素而导致温度场不易收敛问题,在高速大偏心率情况下,油膜温升较高,应考虑温度对轴承性能的影响.流量与供油压力成正比关系,而与转速基本无关.随着转速增加动压效应增强,轻载时轴承在小偏心率下工作.深腔圆锥动静压轴承具有良好的静压浮起和动压润滑特性,理论计算值与试验结果一致,证明理论的正确性,为下一步转子动力学的理论分析打下基础.

关键词：圆锥轴承动静压混合紊流温度场轴心轨迹

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基于电机辅助功能性电刺激脚踏车系统的建模

哈尔滨工程大学学报 2011年第2期32卷 216-222页

作者：姜洪源马长波敖宏瑞陆念力哈尔滨工业大学机电学院黑龙江哈尔滨150001

为了将功能性电刺激技术应用于肢体运动康复,开发一种用于下肢肢体功能重建与运动康复的脚踏车系统,提出了基于电机辅助功能性电刺激脚踏车系统模型,系统包括运动学模型、动力学模型、肌肉刺激模型、电机模型及负载模型.通过Matlab/Simu... 详细信息

为了将功能性电刺激技术应用于肢体运动康复,开发一种用于下肢肢体功能重建与运动康复的脚踏车系统,提出了基于电机辅助功能性电刺激脚踏车系统模型,系统包括运动学模型、动力学模型、肌肉刺激模型、电机模型及负载模型.通过Matlab/Simulink平台建立仿真模型.将实验数据作为输入数据代入模型进行运算.仿真结果与实际实验结果对比,表明模型输出结果与实际结果基本吻合,证明了模型的正确性,为基于模型的功能性电刺激脚踏车闭环反馈控制系统的研制奠定基础.利用该方法可以克服系统启动和负载变化引起的刺激器大脉宽刺激电流输出,可降低肌肉疲劳速度保证训练效果.

关键词：功能性电刺激脚踏车电机辅助系统模型系统仿真

Optimizing Fine-Tuning in Quantized Language Models:An In-Depth Analysis of Key Variables

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Computers, Materials & Continua 2025年第1期82卷 307-325页

作者： ao Shen Zhiquan Lai Dongsheng Li Xiaoyu Hu National Key Laboratory of Parallel and Distributed Computing National University of Defense TechnologyChangsha410073China Strategic Assessments and Consultation Institute Academy of Military ScienceBeijing100091China

Large-scale Language Models(LLMs)have achieved significant breakthroughs in Natural Language Processing(NLP),driven by the pre-training and fine-tuning *** this approach allows models to specialize in specific tasks with reduced training costs,the substantial memory requirements during fine-tuning present a barrier to broader ***-Efficient Fine-Tuning(PEFT)techniques,such as Low-Rank Adaptation(LoRA),and parameter quantization methods have emerged as solutions to address these challenges by optimizing memory usage and computational *** these,QLoRA,which combines PEFT and quantization,has demonstrated notable success in reducing memory footprints during fine-tuning,prompting the development of various QLoRA *** these advancements,the quantitative impact of key variables on the fine-tuning performance of quantized LLMs remains *** study presents a comprehensive analysis of these key variables,focusing on their influence across different layer types and depths within LLM *** investigation uncovers several critical findings:(1)Larger layers,such as MLP layers,can maintain performance despite reductions in adapter rank,while smaller layers,like self-attention layers,aremore sensitive to such changes;(2)The effectiveness of balancing factors depends more on specific values rather than layer type or depth;(3)In quantization-aware fine-tuning,larger layers can effectively utilize smaller adapters,whereas smaller layers struggle to do *** insights suggest that layer type is a more significant determinant of fine-tuning success than layer depth when optimizing quantized ***,for the same discount of trainable parameters,reducing the trainable parameters in a larger layer is more effective in preserving fine-tuning accuracy than in a smaller *** study provides valuable guidance for more efficient fine-tuning strategies and opens avenues for further research into optimizing LLM

关键词： Large-scale Language Model Parameter-Efficient Fine-Tuning parameter quantization key variable trainable parameters experimental analysis

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微通道交流电渗粒子收集位置的确定

微纳电子技术 2009年第2期46卷 99-103,114页

作者：敖宏瑞姜洪源杨胡坤哈尔滨工业大学机电工程学院哈尔滨150001

为了研究在交变电场作用下,样品中的微观粒子被收集到电极表面固定区域的作用机理,通过聚苯乙烯粒子在微通道内的收集实验,得到了粒子及流体的运动规律;基于交流电场作用机理,对电极表面的电势、通道内的电压、电场分布及流体在通道内... 详细信息

为了研究在交变电场作用下,样品中的微观粒子被收集到电极表面固定区域的作用机理,通过聚苯乙烯粒子在微通道内的收集实验,得到了粒子及流体的运动规律;基于交流电场作用机理,对电极表面的电势、通道内的电压、电场分布及流体在通道内的流动过程进行了计算,并用仿真分析进行验证。计算及仿真结果表明,粒子在微电极上的收集位置与实验结果十分吻合,即粒子收集的位置为电极上的固定位置。研究结果为交流电渗粒子收集微通道的设计及相关的粒子收集检测提供了理论与实验基础。

关键词：交流电渗粒子收集微通道数值仿真极化