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某商用车怠速油底壳异响问题分析

应用声学 2024年第1期43卷 76-81页

作者：徐小翔李超曾小春王毅陈齐平江铃汽车股份有限公司产品研发总院南昌330001 江西省汽车噪声与振动重点实验室南昌330001 华东交通大学载运工具与装备教育部重点实验室南昌330013

针对产品开发过程中某柴油车型发动机油底壳怠速时“呜呜”异响问题,通过噪声与振动的测试及仿真分析,对油底壳异响原因进行分析。结果表明,怠速时机油泵的工作激励频率与油底壳模态频率耦合,形成“呜呜”声,并通过油底壳表面辐射出来... 详细信息

针对产品开发过程中某柴油车型发动机油底壳怠速时“呜呜”异响问题,通过噪声与振动的测试及仿真分析,对油底壳异响原因进行分析。结果表明,怠速时机油泵的工作激励频率与油底壳模态频率耦合,形成“呜呜”声,并通过油底壳表面辐射出来。进一步实验研究表明,随着机油温度的升高,机油泵功率、工作激励幅值会逐步减小,异响逐步减小。同时实验研究表明,机油量对油底壳模态频率有影响,油底壳内机油加注量越多,油底壳模态频率越低,油底壳表面振动幅值及异响均逐步减小。针对该异响问题,明确该发动机机油加注上限及下限时油底壳对应频率范围后,通过优化怠速转速,提高油底壳模态频率等使机油泵激励频率与油底壳模态频率避频,解决了该异响问题。

关键词：油底壳机油泵异响

剪切波弹性成像联合盆底超声用于评估不同分娩方式对产后盆底功能影响的价值

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中国药业 2024年第S1期33卷 150-153页

作者：刘青顾欣贤陈小敏陈琪萍苏州大学附属独墅湖医院超声科江苏苏州215000

目的探讨剪切波弹性成像技术联合盆底超声评估不同分娩方式对产后不同时期盆底功能影响的价值。方法选取医院2022年12月至2023年6月分别于产后42 d及产后5个月行盆底检查的产妇82例,按分娩方式的不同分为阴道分娩组(58例)和剖宫产组(24... 详细信息

目的探讨剪切波弹性成像技术联合盆底超声评估不同分娩方式对产后不同时期盆底功能影响的价值。方法选取医院2022年12月至2023年6月分别于产后42 d及产后5个月行盆底检查的产妇82例,按分娩方式的不同分为阴道分娩组(58例)和剖宫产组(24例),应用剪切波弹性成像技术测量产妇静息及缩肛状态下双侧耻骨直肠肌的杨氏模量值,应用盆底超声测量产妇膀胱颈移动度、尿道旋转角及最大ValsalVa状态肛提肌裂孔面积及盆底各器官的位置。结果剖宫产组产后42 d双侧耻骨直肠肌在静息及缩肛状态下的杨氏模量值均显著大于阴道分娩组(P<0.05),膀胱颈移动度、尿道旋转角及最大ValsalVa状态下肛提肌裂孔面积均显著小于阴道分娩组(P<0.05),膀胱膨出发生率显著低于阴道分娩组(P<0.05)。剖宫产组产后5个月膀胱颈移动度显著小于阴道分娩组(P<0.05)。结论剪切波弹性成像联合盆底超声对不同分娩方式产妇产后盆底功能具有较好的评估价值。剖宫产对产后早期的盆底功能具有保护作用,但从远期来看,二者对盆底功能的影响相当。

关键词：剪切波弹性成像盆底超声盆底功能剖宫产阴道分娩

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振动噪声等高图的电驱动桥噪声预测及优化

应用声学 2024年第3期43卷 561-566页

作者：钟秤平王轮郭峰王理周高雅娜陈齐平郭荣江铃汽车股份有限公司南昌330001 江西省汽车噪声与振动重点实验室南昌330001 运载工具与装备教育部重点实验室南昌330013 同济大学上海200092

在项目开发前期通过优化电驱动桥扭矩特性的设计,可以规避噪声大问题。根据电驱动桥台架在对应扭矩下的振动噪声特性,提出了一套稳定高效的测试流程和分析方法。首先设计了一套完整的试验流程,制定了精准的数据分析方法。然后绘制出能... 详细信息

在项目开发前期通过优化电驱动桥扭矩特性的设计,可以规避噪声大问题。根据电驱动桥台架在对应扭矩下的振动噪声特性,提出了一套稳定高效的测试流程和分析方法。首先设计了一套完整的试验流程,制定了精准的数据分析方法。然后绘制出能够全面反映电驱动桥振动噪声特性的等高图。最后利用电驱动桥台架的振动噪声等高图,准确评估电驱动桥加速工况下振动噪声风险,为主机厂和电驱动桥零部件企业提供电驱动桥扭矩特性设计前期指导。利用该方法成功识别到某电驱动桥匀速及加速工况下电机及齿轮的啸叫问题。通过优化电驱动桥扭矩特性设计,电机48阶噪声峰值降低了8.5 dB(A),确认该方法准确可靠,具备推广应用价值。

关键词：电驱动桥振动噪声等高图噪声预测

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融合前馈及状态反馈的智能汽车模型预测控制

湖南大学学报（自然科学版） 2024年第8期51卷 165-175页

作者：陈齐平曹天恒黄少堂江会华江志强时乐泉华东交通大学载运工具与装备教育部重点实验室江西南昌330013 江铃汽车股份有限公司江西南昌330001 江西交通职业技术学院汽车工程学院江西南昌330013

针对具有动力学约束的智能汽车路径精确跟踪问题,提出了一种融合前馈及状态反馈的模型预测控制(model predictive control,MPC)方法.首先,根据车辆二自由度模型建立MPC路径跟踪基础模型,然后考虑基础模型中道路曲率变化对系统产生的已... 详细信息

针对具有动力学约束的智能汽车路径精确跟踪问题,提出了一种融合前馈及状态反馈的模型预测控制(model predictive control,MPC)方法.首先,根据车辆二自由度模型建立MPC路径跟踪基础模型,然后考虑基础模型中道路曲率变化对系统产生的已建模稳态扰动,设计前馈控制器(feed-forward control,FFC)进行消除;并进一步采用比例积分微分(proportional integral derivative,PID)控制器进行系统误差状态反馈调节;最终形成融合前馈及状态反馈转角输入的模型预测最优调节控制律(MPC-FF-PID).最后基于MATLAB/Simulink和Carsim平台证实所提算法的有效性,并基于智能驾驶实车平台在园区低速场景下进行实车测试,最大横向和航向误差分别为0.128 7 m和0.063 9 rad,表明本文算法具备更高的跟踪精度及安全性.

关键词：智能汽车路径跟踪模型预测控制前馈控制状态反馈PID控制仿真与实车验证

Characteristics of Left-Right Spiral Hollow Cylindrical Roller

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Journal of Harbin Institute of Technology(New Series) 2015年第2期22卷 74-78页

作者： Liming Lu qiping chen Yujiang Qin College of Mechanical and Electrical Engineering East China Jiaotong University

Based on new rolling-sliding compound bearings,the wear between the one-way spiral hollow cylindrical roller and the ribs of the inner and outer ring of rolling-sliding compound bearings is reduced by innovational structural design. A new left-right spiral hollow cylindrical roller is proposed to replace the one-way spiral hollow cylindrical roller. The finite element analysis models of ordinary cylindrical rollers,one-way spiral hollow cylindrical rollers and left-right spiral hollow cylindrical rollers are respectively established by *** axial displacement of their center mass and the stress distribution of left-right spiral hollow cylindrical rollers are compared and analyzed. Theoretical study results show that this new left-right spiral hollow cylindrical roller not only inherits the advantages of one-way spiral hollow cylindrical rollers,but also avoids the axial offset and the serious wear of the one-way spiral hollow cylindrical roller. And the theory research conclusion is verified by the experiment. The left-right spiral hollow cylindrical roller has the advantages to overcome boundary stress concentration like logarithmic convex roller. The rolling-sliding compound bearings equipped with the new rollers can be better to adapt to the impact of vibration load.

关键词： left-right spiral hollow cylindrical roller finite element analysis displacement stress

Sliding Mode Control of Hydraulic Pressure in Electro-Hydraulic Brake System Based on the Linearization of Higher-Order Model

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Fluid Dynamics & Materials Processing 2020年第3期16卷 513-524页

作者： qiping chen Haoyu Sun Ning Wang Zhi Niu Rui Wan Key Laboratory of Conveyance and Equipment Ministry of Education East China Jiaotong UniversityNanchang330013China

The possibility to enhance the stability and robustness of electrohydraulic brake(EHB)systems is considered a subject of great importance in the automotive *** such a context,the present study focuses on an actuator with a four-way sliding valve and a hydraulic cylinder.A 4-order nonlinear mathematical model is introduced *** the linearization of the feedback law of the high order EHB model,a sliding mode control method is proposed for the hydraulic *** hydraulic pressure tracking controls are simulated and analyzed by MATLAB/Simulink soft considering separately different conditions,i.e.,a sine wave,a square wave and a square wave with superimposed sine *** results show that the proposed strategy can track the target within 0.25 s,and the mean observed error is less than 1.2 ***,with such a strategy,faster response and less overshoot are possible,which should be regarded as significant advantages.

关键词： EHB hydraulic pressure feedback linearization sliding mode control

Regulation of different light conditions for efficient biomass production and protein accumulation of Spirulina platensis

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Journal of Oceanology and Limnology 2024年第1期42卷 174-186页

作者： Yufei ZHANG Xianjun LI Yuhui LI Shiqi LIU Yanrui chen Miao JIA Xin WANG Lu ZHANG qiping GAO Liang ZHANG Daoyong YU Baosheng GE State Key Laboratory of Heavy Oil Processing and Center for Bioengineering and Biotechnology China University of Petroleum(East China)Qingdao 266580China Tongwei Co. Ltd.Healthy Aquaculture Key Laboratory of Sichuan ProvinceChengdu 610093China

Light plays an important role in the photosynthesis and metabolic process of ***,how different light conditions regulate the biomass production and protein accumulation of microalgae is mostly *** this study,the influence of different light conditions,including light colors,densities,and light:dark cycles on the cell growth and biochemical composition of Spirulina platensis was symmetrically *** different colored lights,*** all shows an increase trend within the increased light intensity ranges;however,each showing different optimal light *** the same light intensity,different colored lights show different growth rate of *** following the sequence of red>white>green>yellow>*** maximum growth rate and protein accumulation were determined as 21.88 and 5.10 mg/(L·d)when illuminated under red *** energy efficiency of different light sources was calculated and ranked as red>white>blue≈green>*** analysis suggests that red light can promote cell growth and protein accumulation by upregulating genes related to photosynthesis,carbon fixation,and C-N metabolism *** study provides a conducive and efficient way to promote biomass production and protein accumulation of *** by regulating light conditions.

关键词： microalgae light emitting diode protein accumulation biomass production transcriptomic analysis

Preparation of uranium targets by electro-deposition method

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Nuclear Science and Techniques 2010年第3期21卷 161-164页

作者： HE Jiaheng chen qiping ZHONG Wenbin LI Xingliang WANG Jing DANG Yufeng LIU Guopin Institute of Nuclear Physics and Chemistry . China Academy of Engineering Physics Mianyang 621900 China

In this paper,uranium targets are prepared by *** uranium dioxide films are electrodeposited into stainless steel plates using uranyl nitrate in ammonium oxalate *** results show that the deposition efficiency of the uranium depends on many parameters,such as pH value,supporting electrolyte, current density,and cell *** uranium films were characterized by infrared spectrum,scanning electron microscope,and X-ray *** uranium films,with a yield of 98%,are in the thickness of about 6 mg·cm^(-2).

关键词：电沉积法铀靶制备扫描电子显微镜支持电解质不锈钢板沉积效率单元设计

Evaluation of physicochemical and functional properties of protein isolates from 5 edible mushroom species

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Food Science and Human Wellness 2024年

作者： Zheng Qian Mengdie Yang Xiao chen qiping Zhan Lei Zhong Qiuhui Hu Liyan Zhao Key Laboratory of Edible Mushroom Processing Ministry of Agriculture and Rural Affairs College of Food Science and Technology Nanjing Agricultural University College of Food Science and Engineering Nanjing University of Finance and Economics

Edible mushroom proteins are the promising ones with the advantages of complete essential amino acid profile and multiple functional activities. To reinforce their applications in functional food development， this study comprehensively evaluated the physicochemical and functional properties of protein isolates from 5 mushroom species， i.e.， Pleurotus eryngii (PEP)， Pleurotus ostreatus (POP)， Lentinula edodes (LEP)， Flammulina velutipes (FVP) and Hypsizygus marmoreus (HMP). Results showed that PEP， LEP， FVP， POP and HMP exhibited better protein solubility (PS)， water holding capacity (WHC)， emulsifying capacity (EAI)， and foaming capacity (FC) than those of soybean protein and pea protein isolates. PEP (51.95%) and POP (49.15%) had a higher amount of β-sheet structure. Principal component analysis and correlation analysis showed that the seven proteins could be divided into 3 clusters， and WHC， EAI and FC were significantly positively correlated with PS and β-sheet. The least gelation concentration of PEP (16%) and FVP (16%) at pH 6.0 and 7.0 was similar to PPI， and PEP showed better hardness， springiness and rheological properties than other proteins gels. Overall， our study showed that 5 edible mushroom proteins possessed excellent functionalities (except for gelling capacity)， which provided novel insights on unexploited sources of mushroom proteins used as protein-based foods in the food industry.

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