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Method for Predicting the Fatigue Life of Geometrically Discontinuous Structures Under Combined Bending and Torsion

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Acta Mechanica Solida Sinica 2019年第3期32卷 367-377页

作者： Jianhui Liu xuemei pan Yaobing Wei Youliang Wang School of Mechanical and Electronical Engineering Lanzhou University of Technology Lanzhou 730050 China

The fatigue damage model based on theory of damage mechanics is capable of predicting the fatigue life under multiaxial loading. Meanwhile, the application of critical plane method in the prediction of multiaxial fatigue life has made certain progress. According to the law of thermodynamics, a new damage evolution equation is developed in the present study to predict the fatigue life of geometrically discontinuous structure under tension-torsion loading based on damage mechanics and the critical plane method. The essence of this approach is tha t the st rain parame ter of the uniaxial nonlinear fatigue damage model is replaced with the equivalent strain, which consists of the releva nt parame ters of the critical plane. However, it is difficult to calculate the stress-strain status and the critical plane position of geometrically dis? continuous structure by theoretical methods because of the existence of stress concentration and the multiaxial nonproportional characteristics. Therefore, a new numerical simulation method is proposed to determine the critical plane of geometrically discontinuous structure under multiaxial loading by means of the finite element method and MATLAB software. The fatigue life of notched specimens subjected to combined bending and torsion is predicted using the proposed met hod, and the result is compared with t hose from the experimen ts and the Manson-Cfiffin law. The comparisons show that the proposed method is superior to the Manson-Coffin law and is capable of reproducing the experimental results reasonably when the geometry of the structure is complex. It completely meets the needs of engineering practice.

关键词： Damage mechanics Critical plane method Geometrically discontinuous structure Finite element method

Probabilistic Fatigue Life Framework of Notched Specimens Based on the Weibull Distribution Under Multiaxial Loading

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Acta Mechanica Solida Sinica 2024年第5期37卷 673-684页

作者： Jie Wang Jianhui Liu Jumei Lu Yingbao He xuemei pan Ziyang Zhang School of Mechanical and Electrical Engineering Lanzhou University of TechnologyLanzhou730050China

In engineering applications,the notch effect and size effect significantly influence the evaluation of fatigue performance in components,necessitating special attention in life *** study proposes a new probabilistic model,based on the theory of critical distance(TCD),to predict fatigue life,with the aim of quantitatively assessing the impact of notch effect and size *** stress distribution on the critical plane is first characterized using a sixth-order multinomial function,and the relative stress gradient function is utilized to calculate the value of the critical ***,the effect of the ratio of shear strain to normal strain on fatigue life under multiaxial loading is ***,the integration of the Weibull distribution into the TCD is employed for conducting probabilistic modeling of fatigue ***,fatigue experiments are conducted on notched specimens of Q355D steel,demonstrating that the life prediction results under 50%survival probability are superior to the traditional TCD method.

关键词： Theory of critical distance(TCD) Notch effect Size effect Strain ratio Weibull distribution

SMC for Rudder/Fin Joint Roll Stabilization Based on Input-output Feedback Linearization 36

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SMC for Rudder/Fin Joint Roll Stabilization Based on Input-o...

GC-MS/MS Method for Determination and Pharmacokinetics of Main Components of Cang-Ai Volatile Oil in Rat Plasma after Intravenous Administration

第36届中国控制会议

作者： Hui Li xuemei pan Chen Guo Information Science and Technology College Dalian Maritime University Automation and Electrical Engineering College Linyi University

ISBN: (纸本)9781538629185

In order to ensure the accuracy of course control and achieve good performance on roll stabilization, this paper designs rudder/fin joint SMC system, thereby improving ship’s course stability, security and comfort of crew and passenger. Aiming at ship motion with the features of nonlinearity, strong coupling, multivariable and complex sea condition, this paper establishes the ship motion mathematical model of 4 degrees of freedom, which can more fully reflect the nonlinear essence of ship motion. On this basis, in view of the features of sliding mode variable structure control which is to insensitive in disturbance and model error, combining the theory of nonlinear differential geometry, the sliding mode controller based on the input-output feedback linearization is designed and applied to rudder/fin joint roll stabilization control system. The simulation results show that the controller has good robustness, and the control system can achieve better performance on roll stabilization while maintaining the accuracy of course control.

关键词： Rudder/Fin Joint Roll Stabilization SMC Feedback Linearization

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Medicinal Plant 2024年第4期15卷 92-98页

作者： Wenyu MA Jincun LI xuemei pan Haoran NI Yuhuan XIE School of Chinese Materia Medica Yunnan University of Chinese MedicineKunming 650500China Yunnan Provincial University Key Laboratory of Aromatic Chinese Herb Research Kunming 650500China Yunnan Innovation Team of Application Research on Traditional Chinese Medicine Theory of Disease Prevention at Yunnan University of TCM Kunming 650500China

[Objectives]To establish a gas chromatography-triple quadrupole mass spectrometry(GC-MS/MS)method based on multiple reaction monitoring(MRM)mode for the analysis of the major components in Cang-ai volatile oil(CAVO).[Methods]An ultrasensitive gas chromatography-tandem mass spectrometry(GC-MS/MS)method was developed and validated for the determination of three highly abundant components in rat plasma *** was used as an internal standard.A multiple reaction monitoring(MRM)model was employed for the quantification of the three major components of CAVO.[Results]The method demonstrated linearity over the range of 0.25 to 50μg/mL with a correlation coefficient(R 2)greater than *** lower limit of quantification was 0.25μg/***-day and inter-day accuracy and precision were within 15%.Extraction recovery and matrix effect values ranged from 90.1%to 110.6%and 0.1%to 2.1%,respectively.[Conclusions]This method was successfully applied to the simultaneous determination of the three components in high-level CAVO plasma samples,providing a basis for subsequent studies of CAVO.

关键词： GC-MS/MS Cang-ai volatile oil MRM mode Pharmacokinetics

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唑来膦酸原研药与仿制药质量差异研究

中国骨质疏松杂志 2016年第12期22卷 1585-1589页

作者：潘雪梅房德敏高颖天津市天津医院药学部天津300211

目的对唑来膦酸注射液原研药与仿制药进行质量差异考察。方法选取不同厂家不同批次唑来膦酸原研药与仿制药,参照唑来膦酸注射液的药品标准,从渗透压、不溶性微粒、有关物质检查、含量测定等方面对比药品质量差异。结果原研药渗透压均近... 详细信息

目的对唑来膦酸注射液原研药与仿制药进行质量差异考察。方法选取不同厂家不同批次唑来膦酸原研药与仿制药,参照唑来膦酸注射液的药品标准,从渗透压、不溶性微粒、有关物质检查、含量测定等方面对比药品质量差异。结果原研药渗透压均近等渗范围,仿制药偏低渗范围,分别为274 m Osmol/kg、260 m Osmol/kg;仿制药中≥1μm的小粒径不溶性微粒显著多于原研药,粒径≥10μm、≥25μm的微粒彼此间差异不大,动态颗粒成像检测技术（Flow CAM）的检测结果普遍略高于光阻法;原研药唑来膦酸含量稳定,仿制药波动较大,分别相当于对照品的99.10%、103.82%;有关物质检查结果差异不大,杂质种类相同,总杂质含量为0.13%~0.18%,仿制药中保留时间（RT）7.15 min杂质高于原研药,RT11.21 min杂质低于原研药。结论唑来膦酸原研药与仿制药各项检查项目均符合药品标准,但仿制药在渗透压、≥1μm的小粒径不溶性微粒及含量稳定性方面,与原研药仍存在一定质量差异。

关键词：唑来膦酸注射液原研药仿制药质量差异

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考虑应力梯度的多轴缺口件疲劳寿命预测方法

华中科技大学学报（自然科学版） 2021年第3期49卷 80-85页

作者：刘俭辉潘雪梅华飞龙戴宝林兰州理工大学机电工程学院甘肃兰州730050

以缺口附近疲劳损伤影响区的场强为损伤参量,结合Manson-Coffin方程提出一种多轴比例加载下缺口件疲劳寿命预估方法.首先,借助坐标变换矩阵定义应变能密度最大的平面为临界面,克服了传统能量法作为标量难以描述裂纹萌生和扩展方向的不足... 详细信息

以缺口附近疲劳损伤影响区的场强为损伤参量,结合Manson-Coffin方程提出一种多轴比例加载下缺口件疲劳寿命预估方法.首先,借助坐标变换矩阵定义应变能密度最大的平面为临界面,克服了传统能量法作为标量难以描述裂纹萌生和扩展方向的不足.其次,利用有限元软件分析临界面上等效应力分布规律,拟合距离危险点5 mm内等效应力分布函数,通过求相对应力梯度函数的驻点确定疲劳损伤影响区的大小,以疲劳损伤影响区的场强作为疲劳损伤参量对Q345钢多轴缺口件进行寿命预估.最后,将利用该方法、局部应力应变法的预估寿命与试验寿命进行对比,结果表明:两种方法预估寿命的误差都在2倍因子以内,但由于该方法考虑了应力梯度效应,预估精度要优于局部应力应变法.

关键词：多轴疲劳缺口寿命预测应力梯度效应临界面法

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'全国文明村'繁荣村

文化交流 2009年第10期 7-10页

作者：潘雪梅

2009年5月22日下午,浙江电视台公共新农村频道与台州市黄岩区在橘乡院桥繁荣村联合举办'浙江农民创富大赛'文艺专场演出.在村剧场里,来自省、区的文艺工作者和当地农民联袂演出了歌舞、魔术,武术、器乐等节目,赢得了四邻八乡观众的阵阵... 详细信息

2009年5月22日下午,浙江电视台公共新农村频道与台州市黄岩区在橘乡院桥繁荣村联合举办'浙江农民创富大赛'文艺专场演出.在村剧场里,来自省、区的文艺工作者和当地农民联袂演出了歌舞、魔术,武术、器乐等节目,赢得了四邻八乡观众的阵阵掌声.

关键词：浙江电视台文艺工作者演出农民农村频道台州市黄岩区武术器乐魔术剧场节目观众歌舞大赛

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桥巩水电站定子接地保护无选择性的整改

科技传播 2010年第14期2卷 170-171页

作者：潘雪梅广西方元电力股份有限公司桥巩水电站分公司广西来宾546119

本文介绍了桥巩水电站发电机组定子接地保护无无选择性的整改方案及试验结果。采用机端电流计算零率功率作为零序功率方向元件,实现两机一变扩大单元接线下的定子接地保护选择。

关键词：桥巩水电站定子接地保护误动选择性零序电流采样

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岛国的远眺——立足于亚洲的福冈

当代美术家 2005年第5期 22-23页

作者：潘雪梅不详

在太平洋优美的西岸沿线,日本列岛如同首尾相接的狭长裂隙,在这片汪洋的碧波中划下了一道不经意的弧度。然而,四面环海的孤独或吞云吐雾的火山,都没有让这个常年櫻花盛开的国度走向落寞和封闭,恰恰相反,这个先天上曾被人耻笑的“地理儒... 详细信息

在太平洋优美的西岸沿线,日本列岛如同首尾相接的狭长裂隙,在这片汪洋的碧波中划下了一道不经意的弧度。然而,四面环海的孤独或吞云吐雾的火山,都没有让这个常年櫻花盛开的国度走向落寞和封闭,恰恰相反,这个先天上曾被人耻笑的“地理儒”,在数千年的历史变迁中,却成为世界版图里一块不容忽视的弹丸之地。或许,正是因为地缘面貌上的局限,从来没有任何一个国家,像日本一样急于将它的触角向外延伸。将目光长远地眺向岛国的别处。今天,其九州北部的福冈亚洲美术馆和它所举办的福冈艺术三年展,已经在艺术领域显示了它在亚洲和世界范围内枝蔓纵横的深远影响。

关键词：福冈日本列岛首尾相接美术馆向外延伸岛国历史变迁