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时速250 km动车组底架端部焊接变形研究

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焊接技术 2024年第1期53卷 131-135页

作者：葛少平赵丽玲宋峥王红伟殷丽荣中车唐山机车车辆有限公司河北唐山063035

文中以时速250 km动车组底架焊接变形为例,对底架焊接过程中地板产生的焊接变形进行分析,通过优化焊接工艺,选择合理的焊接顺序和焊接工艺参数、预制反变形等措施控制焊接变形,总结出一套最适合底架生产的工艺方案,提升产品质量,提高生... 详细信息

文中以时速250 km动车组底架焊接变形为例,对底架焊接过程中地板产生的焊接变形进行分析,通过优化焊接工艺,选择合理的焊接顺序和焊接工艺参数、预制反变形等措施控制焊接变形,总结出一套最适合底架生产的工艺方案,提升产品质量,提高生产效率,降低制造成本。

关键词：底架组成焊接变形焊接工艺

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高速动车组端墙焊接变形控制

电焊机 2018年第3期48卷 344-348页

作者：赵丽玲葛少平唐衡郴桂洪利于岩中车唐山机车车辆有限公司河北唐山063035

高速动车组端墙是铝合金车体的重要组成部位,结构复杂、附件多、焊接量大,焊接变形比较大。焊接变形是由于焊接过程中的加热、冷却不均匀引起,而铝合金的变形相对较大,影响焊接结构的制造和使用性能。本文以一种标准动车组端墙为研究对... 详细信息

高速动车组端墙是铝合金车体的重要组成部位,结构复杂、附件多、焊接量大,焊接变形比较大。焊接变形是由于焊接过程中的加热、冷却不均匀引起,而铝合金的变形相对较大,影响焊接结构的制造和使用性能。本文以一种标准动车组端墙为研究对象,通过在端墙的生产制造过程当中,采取适当的工装优化、装配工艺和合理的焊接顺序,有效控制了端墙的焊接变形,保证了端墙的平面度和轮廓度,降低了端墙调修工作强度,提高了生产效率,满足批量生产的需求。不仅如此,本文的控制方法对其他动车组端墙的制造有很好的借鉴意义,推广价值良好。

关键词：端墙焊接变形装配工艺焊接顺序

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地铁车辆车体铝合金底架焊接变形及工艺研究

焊接技术 2023年第11期52卷 61-64页

作者：唐衡郴张立杰葛少平聂丽丽刘伟洁中车唐山机车车辆有限公司河北唐山063035

文中以B型地铁车辆车体铝合金底架的焊接变形为例,对地铁车辆铝合金底架产生焊接变形的原因进行分析,通过选择合理的制造工艺流程、良好的装配质量、合理的焊接工艺、预制反变形等措施控制焊接变形,从而实现尺寸控制,总结出一套最适合... 详细信息

文中以B型地铁车辆车体铝合金底架的焊接变形为例,对地铁车辆铝合金底架产生焊接变形的原因进行分析,通过选择合理的制造工艺流程、良好的装配质量、合理的焊接工艺、预制反变形等措施控制焊接变形,从而实现尺寸控制,总结出一套最适合底架生产的工艺方案,减少底架调修,提升产品质量,提高生产效率,降低制造成本。

关键词：底架组成焊接变形尺寸控制反变形

Flow field and pressure loss analysis of junction and its structure optimization of aircraft hydraulic pipe system

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Chinese Journal of Aeronautics 2013年第4期26卷 1080-1092页

作者： Li Xin Wang shaoping School of Automation Science and Electric Engineering Beihang University Science and Technology on Aircraft Control Laboratory Beihang University

The flow field in junction is complicated due to the ripple property of oil flow velocity and different frequencies of two pumps in aircraft. In this study, the flow fields of T-junction and Y-junction were analyzed using shear stress transport （SST） model in ANSYS/CFX software. The simulation results identified the variation rule of velocity peak in T-junction with different frequencies and phase-differences, meanwhile, the eddy and velocity shock existed in the corner of the T-junction, and the limit working state was obtained. Although the eddy disappeared in Y-junction, the velocity shock and pressure loss were still too big. To address these faults, an arc-junction was designed. Based on the flow fields of arc-junction, the eddy in the junction corner disappeared and the maximum of velocity peak declined compared to T-and Y-junction. Additionally, 8 series of arc-junction with different radiuses were tested to get the variation rule of velocity peak. Through the computation of the pressure loss of three junctions, the arc-junction had a lowest loss value, and its pressure loss reached the minimum value when the curvature radius is 35.42 mm, meanwhile, the velocity shock has decreased in a low phase.

关键词： Arc-junction Computational fluid dynam- ics Pipe flow Pressure loss T-junction Velocity shock Y-junction

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板梁结构铝合金端墙焊接变形研究

电焊机 2018年第3期48卷 314-316页

作者：葛少平赵丽玲王陆钊赵嵩岩张忠海中车唐山机车车辆有限公司河北唐山063035

以铝合金端墙焊接变形为例,分析板梁结构的铝合金端墙产生焊接变形原因,通过选择合理的组焊顺序、良好的装配质量、合理的焊接工艺、预制反变形等措施控制焊接变形,总结出一套适合端墙生产的工艺方案,降低了调修难度,减少了调修工作量,... 详细信息

以铝合金端墙焊接变形为例,分析板梁结构的铝合金端墙产生焊接变形原因,通过选择合理的组焊顺序、良好的装配质量、合理的焊接工艺、预制反变形等措施控制焊接变形,总结出一套适合端墙生产的工艺方案,降低了调修难度,减少了调修工作量,提高了生产效率,获得高质量的产品。

关键词：端墙组成焊接变形装配顺序反变形

Autonomic dysreflexia: a cardiovascular disorder following spinal cord injury

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Neural Regeneration Research 2017年第9期12卷 1390-1400页

作者： Hisham Sharif shaoping Hou Spinal Cord Research Center Department of Neurobiology and Anatomy Drexel University College of Medicine

Autonomic dysreflexia （AD） is a serious cardiovascular disorder in patients with spinal cord injury （SCI）. The primary underlying cause of AD is loss of supraspinal control over sympathetic preganglionic neurons （SPNs） caudal to the injury, which renders the SPNs hyper-responsive to stimulation. Central maladaptive plasticity, including C-fiber sprouting and propriospinal fiber proliferation exaggerates noxious afferent transmission to the SPNs, causing them to release massive sympathetic discharges that result in severe hypertensive episodes. In parallel, upregulated peripheral vascular sensitivity following SCI exacerbates the hypertensive response by augmenting gastric and pelvic vasoconstriction. Currently, the majority of clinically employed treatments for AD involve anti-hypertensive medications and Botox injections to the bladder. Although these approaches mitigate the severity of AD, they only yield transient effects and target the effector organs, rather than addressing the primary issue of central sympathetic dysregulation. As such, strategies that aim to restore supraspinal reinnervation of SPNs to improve cardiovascular sympathetic regulation are likely more effective for AD. Recent pre-clinical investigations show that cell transplantation therapy is efficacious in reestablishing spinal sympathetic connections and improving hemodynamic per- formance, which holds promise as a potential therapeutic approach.

关键词： autonomic dysreflexia hyper-reflexia sympathetic dysfunction C-fibers propriospinal axons a-adrenoceptors stem cell transplantation

Analysis of Cordyceps by multi-column liquid chromatography

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Acta Pharmaceutica Sinica B 2017年第2期7卷 202-207页

作者： Zhengming Qian shaoping Li Institute of Chinese Medical Sciences University of MacaoMacaoChina Key Laboratory of State Administration of Traditional Chinese Medicine Sunshine Lake Pharma Co.Ltd.Dongguan 523850China

Cordyceps is a famous traditional Chinese medicine (TCM) that has been used in China for hundreds of years. In the present study a multi-column liquid chromatography (MC-LC) system was developed for the qualitative analysis of macromolecules and micromolecules in Cordyceps. The MC-LC system includes a size exclusion pre-column, a size exclusion column (SEC) and a reversed phase column (RP) which were controlled by column-switching valves. The sample was separated by the size exclusion pre-column into two fractions (macromolecules and micromolecules). These fractions were further separated on SEC and RP columns, respectively. A diode array detector (DAD) and a mass spectrometer (MS) were used to detect the components. This MC-LC method was utilized for analysis of Cordyceps samples. Two macromolecular peaks and 15 micromolecular peaks were found in Cordyceps, and 11 of the micromolecular peaks were identified as adenosine-5'-monophosphate (AMP), phenylalanine, uridine, hypoxanthine, inosine, guanine, guanosine, deoxyadenosine-5'-monophosphate (dAMP), adenosine, adenine and cordycepin (or its isomer). This method is useful for quality control of Cordyceps. (C) 2017 Chinese Pharmaceutical Association and Institute of Materia Medica, Chinese Academy of Medical Sciences. Production and hosting by Elsevier B.V.

关键词： Cordycepie Macromocules Micromolecules Multi-column Size exclusion column

Relay strategies combined with axon regeneration: a promising approach to restore spinal cord injury

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Neural Regeneration Research 2014年第12期9卷 1177-1179页

作者： shaoping Hou Spinal Cord Research Center Department of Neurobiology & Anatomy Drexel University College of Medicine

For decades, numerous investigations have only focused on axon regeneration to restore function after traumatic spinal cord injury （SCI）, as interrupted neuronal pathways have to be reconnected for sensorimotor and autonomic recovery to occur. Experimental approaches have ranged from drug delivery and cell transplantation to genetic manipulations. Certainly, it would be an extraordinary achievement for injured axons to regenerate over long distances, to form synapses with target neurons, and to result in dramatic functional improvement. However, these efforts have been rewarded with limited success to date suggesting that axon regeneration alone may be insufficient to repair compromised functions.

关键词： a promising approach to restore spinal cord injury NSCs SCI

Remaining useful life prediction based on the Wiener process for an aviation axial piston pump

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Chinese Journal of Aeronautics 2016年第3期29卷 779-788页

作者： WangXingjian LinSiru Wang shaoping HeZhaomin ZhangChao School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100083China Beijing Aeronautical Science&Technology Research Institute of COMAC Beijing 102211China

An aviation hydraulic axial piston pump＇s degradation fiom comprehensive wear is a typical gradual failure model. Accurate wear prediction is difficult as random and uncertain char- acteristics must be factored into the estimation. The internal wear status of the axial piston pump is characterized by the return oil flow based on fault mechanism analysis of the main frictional pairs in the pump. The performance degradation model is described by the Wiener process to predict the remaining useful life （RUL） of the pump. Maximum likelihood estimation （MLE） is performed by utilizing the expectation maximization （EM） algorithm to estimate the initial parameters of the Wiener process while recursive estimation is conducted utilizing the Kalman filter method to estimate the drift coefficient of the Wiener process. The RUL of the pump is then calculated accord- ing to the performance degradation model based on the Wiener process. Experimental results indi- cate that the return oil flow is a suitable characteristic for reflecting the internal wear status of the axial piston pump, and thus the Wiener process-based method may effectively predicate the RUL of the pump.

关键词： Axial piston pump Hydraulic system Remaining useful lifeReturn oil flow Wear Wiener process