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Journal of Materials Science & Technology 2024年第1期168卷 208-214页

作者： Huimin Zhang Yachao wang Zuhair A.Munir Yongzhong Zhang Wenhao Fan shaoping Chen College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan030024China Capital Aerospace Machinery Company Beijing100076China Department of Material Science and Engineering University of CaliforniaDavisCalifornia95616United States of America College of Physics and Optoelectronics Taiyuan University of TechnologyTaiyuan030024China Instrumental Analysis Center of Taiyuan University of Technology Taiyuan030024China

Mg_(3)Sb_(2)-based thermoelectric materials have been the focus of widespread investigations as promising candidates for the harvesting of waste heat.Interface stability and service performance are key points for the commercial applications of these materials.We utilized Mg_(4.3)Sb_(3)Ni as a barrier layer to improve the thermal stability of Mg 3 Sb 2-based devices.However,its intrinsic high resistivity contributed nega-tively to the desired performance of the device.In this work,we investigated two other Mg-Sb-Ni ternary phases,MgSbNi and MgSbNi_(2),as new barrier layer materials to connect with Mg_(3.2)Sb_(2)Y_(0.05).The results show that the efficiency of the Mg_(1.2)SbNi/Mg_(3.2)Sb_(2)Y_(0.05)/Mg_(1.2)SbNi joint is increased by 33%relative to the higher Mg-content barriers due to lower resistivity.The system exhibited good interfacial compatibility and showed little change with aging at 673 K for 20 days.

关键词： Mg_(3)Sb_(2) Mg_(1.2)SbNi Barrier layer Conversion efficiency

Preliminary Results of the Seismicity Monitoring Experiment around the 2019 Mw5.4 Earthquake Epicenter in the Central South China Sea Basin

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Journal of Earth Science 2024年第1期35卷 212-220页

作者： Wenfei Gong Aiguo Ruan Xiongwei Niu Zhenjie wang Pingchuan Tan Xiaodong Wei Wei wang Zhengyi Tong Liqun Cheng Fansheng Kong shaoping Lu Jianke Fan Weiwei Ding Jinyao Gao Chunguo Yang Jiabiao Li School of Oceanography Shanghai Jiaotong UniversityShanghai 200240China Key Laboratory of submarine Geosciences Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China Zhejiang Earthquake Administration Hangzhou 310013China School of Earth Sciences Zhejiang UniversityHangzhou 310027China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519082China School of Earth Sciences and Engineering Sun Yat-sen UniversityZhuhai 519082China Institute of Oceanology Chinese Academy of SciencesQingdao 266071China

On September 5,2019,a moderate earthquake of Mw5.4 unexpectedly occurred in the apparently quiescent central basin of the South China Sea.We immediately carried out a seismicity monitoring experiment around the epicenter by using broadband ocean bottom seismometers(OBS)for the following three scientific targets.The first is knowing the earthquake seismogenic mechanism,fault structure and further development.The second is finding the role of the residual spreading ridge playing in earthquake processes and further revealing the deep structures of the ridge directional turning area.The third is confirming the existence and significance of the so called“Zhongnan fault”.This paper reports the preliminary results of the first phase experiment.Five OBSs were deployed for seismicity monitoring with a duration of 288 days,but only three were recovered.Micro-earthquakes were firstly detected by an automatic seismic phase picking algorithm and then were verified by analyzing their seismic phases and time-frequency characteristics in detail.A total of 21,68 and 89 microearthquakes were picked out from the three OBSs respectively within the distance of 30 km.The dominant frequency of these micro-earthquakes is 12-15 Hz,indicating tectonic fracturing.During the first two months after the mainshock the seismicity was relatively stronger,and micro-earthquakes were still occurring occasionally till the end of observation,indicating the epicenter area is active.We used Match&Locate method to locate 57 micro-earthquakes preliminarily.Their spatial distribution shows that the seismicity is developed mainly along the NE direction roughly parallel to the residual ridge with depth variations between 10-20 km.

关键词： South China Sea microseismic monitoring earthquakes fault broadband OBS

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

基于数字孪生的机电液系统PHM关键技术综述

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机械工程学报 2024年第4期60卷 66-81页

作者：石健刘冬王少萍天目山实验室杭州310023 北京航空航天大学自动化科学与电气工程学院北京100191

数字孪生(Digital twin,DT)技术与预测和健康管理(Prognostics and health management,PHM)技术是智能制造领域中的两个热点研究方向。在对PHM技术现状总结分析的基础上,归纳当前制约PHM技术发展和应用的关键性问题如下:设备故障机理研... 详细信息

数字孪生(Digital twin,DT)技术与预测和健康管理(Prognostics and health management,PHM)技术是智能制造领域中的两个热点研究方向。在对PHM技术现状总结分析的基础上,归纳当前制约PHM技术发展和应用的关键性问题如下:设备故障机理研究不透彻、全生命周期数据不完备、健康状态监测方法不足、多层级状态信息综合不足以及不确定性管理问题。并阐述数字孪生技术在解决这些问题过程中的独特优势,提出将基于第一性原理的多维数字孪生模型构建、虚实空间的多维数据映射、孪生体技术状态一致性度量与模型的高效迭代修正以及基于多域特征的系统健康评估、预测与维护决策作为关键技术构建DT-PHM研究架构。随着技术不断推进与发展,两项技术深度融合,基于数字孪生的复杂系统健康管理技术必将成为未来装备全生命周期视情维修和预测性维修的关键技术之一。

关键词：复杂机电液系统数字孪生健康管理预测性维护状态监控

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大型民机操纵系统容错控制技术综述

机械工程学报 2024年第4期60卷 50-65页

作者：王兴坚杨新宇王少萍北京航空航天大学自动化科学与电气工程学院北京100191 北京航空航天大学能源与动力工程学院北京100191

大型民机操纵系统是飞机姿态调整与保持的关键系统,在飞行过程中,操纵系统故障会使飞机控制性能下降,严重时甚至导致飞机响应发散,造成严重后果。深入研究飞行过程中操纵系统的容错控制技术对于提升飞行控制性能、保障系统稳定运行具有... 详细信息

大型民机操纵系统是飞机姿态调整与保持的关键系统,在飞行过程中,操纵系统故障会使飞机控制性能下降,严重时甚至导致飞机响应发散,造成严重后果。深入研究飞行过程中操纵系统的容错控制技术对于提升飞行控制性能、保障系统稳定运行具有重要意义。从控制的角度出发,对目前大型民机操纵系统的容错控制方法进行归纳和总结。首先,介绍飞机操纵系统组成并分析系统的主要故障类型,包括舵面故障、作动器故障、传感器故障及过程故障等;其次,深入讨论飞机操纵系统的容错控制技术进展,比较并归纳各种容错控制方法的优缺点;再次,阐述飞机操纵系统的冗余资源配置及其在容错控制中的作用;最后,总结操纵系统容错控制技术在实际工程中的应用,并对飞机操纵系统容错控制领域目前面临的主要技术挑战和机遇进行展望。

关键词：飞行操纵系统容错控制作动器故障余度资源

An accelerated life test model for harmonic drives under a segmental stress history and its parameter optimization

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Chinese Journal of Aeronautics 2015年第6期28卷 1758-1765页

作者： Zhang Chao wang shaoping wang Zimeng wang Xingjian School of Automation Science and Electrical Engineering Beihang University Beijing 100191 China Science and Technology on Aircraft Control Laboratory Beihang University Beo'ing 100191 China

Harmonic drives have various distinctive advantages and are widely used in space drive mechanisms. Accelerated life test （ALT） is commonly conducted to shorten test time and reduce associated costs. An appropriate ALT modet is needed to predict the lifetime of harmonic drives with ALT data. However, harmonic drives which are used in space usually work under a segmental stress history, and traditional ALT models can hardly be used in this situation. This paper proposes a dedicated ALT model for harmonic drives applied in space systems. A comprehensive ALT model is established and genetic algorithm （GA） is adopted to obtain optimal parameters in the model using the Manson fatigue damage rule to describe the fatigue failure process and a cumulative dam- age method to calculate and accumulate the damage caused by each segment in the stress history. An ALT of harmonic drives was carried out and experimental results show that this model is acceptable and effective.

关键词： Accelerated life testing Cumulative fatigue damagelaw Genetic algorithm Harmonic drive Segmental stress history

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

Active fault-tolerant control strategy of large civil aircraft under elevator failures

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Chinese Journal of Aeronautics 2015年第6期28卷 1658-1666页

作者： wang Xingjian wang shaoping Yang Zhongwei Zhang Chao School of Automation Science and Electrical Engineering Beihang University

Aircraft longitudinal control is the would lead to catastrophic accident of aircraft. most important actuation system and its failures This paper proposes an active fault-tolerant control （AFTC） strategy for civil aircraft with different numbers of faulty elevators. In order to improve the fault-tolerant flight control system performance and effective utilization of the control surface, trim- mable horizontal stabilizer （THS） is considered to generate the extra pitch moment. A suitable switching mechanism with performance improvement coefficient is proposed to determine when it is worthwhile to utilize THS. Furthermore, AFTC strategy is detailed by using model following technique and the proposed THS switching mechanism. The basic fault-tolerant controller is designed to guarantee longitudinal control system stability and acceptable performance degradation under partial elevators failure. The proposed AFTC is applied to Boeing 747-200 numerical model and simulation results validate the effectiveness of the proposed AFTC approach.

关键词： Active fault-tolerant control Longitudinal control Model following Performance improvementcoefficient Trimmable horizontalstabilizer

Chinese Society of Cardiology guidelines on the diagnosis and treatment of adult fulminant myocarditis

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Science China(Life Sciences) 2024年第5期67卷 913-939页

作者： Chinese Society of Cardiology,Chinese Medical Association,Writing Group Jiangang Jiang Hongyang Shu Dao Wen wang Rutai Hui Chenze Li Xiao Ran Hong wang Jing Zhang shaoping Nie Guanglin Cui Dingcheng Xiang Qun Shao Shengyong Xu Discussion experts:Ning Zhou Yuming Li Wei Gao Yuguo Chen Yuan Bian Guoping wang Liming Xia Yan wang Chunxia Zhao Zhiren Zhang Yuhua Zhao Jianan wang Shaoliang Chen Hong Jiang Jing Chen Xianjin Du Mao Chen Yinxian Sun Sheng Li Hu Ding Xueping Ma Hesong Zeng Li Lin Shenghua Zhou Likun Ma Ling Tao Juan Chen Yiwu Zhou Xiaomei Guo 不详 Tongji Hospital Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Fuwai Hospital National Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100037China Zhongnan Hospital of Wuhan University Wuhan 430062China Fuwai Huazhong Cardiovascular Hospital Zhengzhou 450003China Beijing Anzhen Hospital Capital Medical UniversityBeijing 100029China Guangzhou General Hospital of Guangzhou Military Command Guangzhou 510010China Harbin Medical University Cancer Hospital Harbin 150081China Union Hospital Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China Taida Hospital Tianjin 300457China Peking University Third Hospital Beijing 100191China Qilu Hospital of Shandong University Jinan 250012China Kanghua Hospital DongguanGuangzhou 523080China Second Affiliated Hospital Zhejiang University School of Medicine Hangzhou 310003China Nanjing First Hospital Nanjing Medical UniversityNanjing 210006China Renmin Hospital of Wuhan University Wuhan 430060Wuhan West China Hospital Sichuan UniversityChengdu 610044China First Hospital of China Medical University Shenyang 110002China General Hospital of Ningxia Medical University Yinchuan 750003China The Second Xiangya Hospital Central South UniversityChangsha 410012China The First Affiliated Hospital of USTC University of Science and Technology of ChinaHefei 230002China The First Affiliated Hospital of Air Force Medical University Xi’an 710032China Central Hospital of Wuhan City Wuhan 430014China Tongji Medical College Huazhong University of Science and TechnologyWuhan 430030China

Fulminant myocarditis is an acute diffuse inflammatory disease of myocardium.It is characterized by acute onset,rapid progress and high risk of death.Its pathogenesis involves excessive immune activation of the innate immune system and formation of inflammatory storm.According to China’s practical experience,the adoption of the“life support-based comprehensive treatment regimen”(with mechanical circulation support and immunomodulation therapy as the core)can significantly improve the survival rate and long-term prognosis.Special emphasis is placed on very early identification,very early diagnosis,very early prediction and very early treatment.

关键词： fulminant myocarditis guidelines life support-based comprehensive treatment regimen diagnosis treatment cytokine storm overactivation of immunity

Nonlinear dynamic modeling of a helicopter planetary gear train for carrier plate crack fault diagnosis

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Chinese Journal of Aeronautics 2016年第3期29卷 675-687页

作者： Fan Lei wang shaoping wang Xingjian Han Feng Lyu Huawei School of Automation Science and Electrical Engineering Beihang University 41th Detachment People’s Liberation Army Troop 61267

Planetary gear train plays a significant role in a helicopter operation and its health is of great importance for the flight safety of the helicopter. This paper investigates the effects of a planet carrier plate crack on the dynamic characteristics of a planetary gear train, and thus finds an effec- tive method to diagnose crack fault. A dynamic model is developed to analyze the torsional vibra- tion of a planetary gear train with a cracked planet carrier plate. The model takes into consideration nonlinear factors such as the time-varying meshing stiffness, gear backlash and viscous damping. Investigation of the deformation of the cracked carrier plate under static stress is performed in order to simulate the dynamic effects of the planet carrier crack on the angular displacement of car- rier posts. Validation shows good accuracy of the developed dynamic model in predicting dynamic characteristics of a planetary gear train. Fault features extracted from predictions of the model reveal the correspondence between vibration characteristic and the conditions （length and position） of a planet carrier crack clearly.

关键词： Angular shift Carrier plate crack Crack fault diagnosis Helicopter planetary geartrain Nonlinear dynamicsmodeling