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Internal structural optimization of hollow fan blade based on sequential quadratic programming algorithm

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航空动力学报 2011年第4期26卷 787-793页

作者： yanG Jian-qiu wang yan-rong School of Jet Propulsion Beijing University of Aeronautics and Astronautics Beijing 100191 China

Several structural design parameters for the description of the geometric features of a hollow fan blade were determined.A structural design optimization model of a hollow fan blade which based on the strength constraint and minimum mass was established based on the finite element method through these ***,the sequential quadratic programming algorithm was employed to search the optimal *** groups of value for initial design variables were chosen,for the purpose of not only finding much more local optimal results but also analyzing which discipline that the variables according to could be benefit for the convergence and *** surface method and Monte Carlo simulations were used to analyze whether the objective function and constraint function are sensitive to the variation of variables or *** the robust results could be found among a group of different local optimal solutions.

关键词： hollow fan blade structural optimization sequential quadratic algorithm finite element method Monte Carlo simulations

Fragmentation of N2 in 410 nm Intense Femtosecond Laser Field

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Chinese Journal of Chemical Physics 2009年第1期22卷 1-6页

作者： Wei Guo Jing-yi Zhu yan-qiu wang Li wang State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China Graduate School of Chinese Academy of Sciences Beijing 100049 China

Fragmentations of N2 in linearly polarized femtosecond 410 and 820 nm intense laser fields were studied by using the velocity mapping technique. Different behaviors of N2 at 410 and 820 nm were observed. Both the kinetic energy distributions and angular distributions of fragment ions in 410 nm field show weak dependency on laser intensities in the non- saturation regime, in contrast to the case in 820 nm. Different excited electronic states, i.e., non-Coulombic potentials populated via vertical＇excitation, are suggested to play crucial roles in fragmentations at short wavelength.

关键词： Velocity mapping Non-Coulombic fragmentation Energy distribution Angular distribution

The relationship between serum miR-21 levels and left atrium dilation in elderly patients with essential hypertension

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Journal of Geriatric Cardiology 2022年第11期19卷 833-842页

作者： yan wang Guang-Ping FU qiu-yan wang Ting-Ting ZHANG Li-Li HE Qing-Juan ZUO Chang-Lei ZHANG Yi-Fang GUO Department of Geriatric Cardiology Hebei General HospitalShijiazhuangHebeiChina Hebei Key Laboratory of Forensic Medicine Department of Forensic MedicalHebei Medical UniversityShijiazhuangHebeiChina Hebei Medical University ShijiazhuangHebeiChina

BACKGROUND MicroRNA-21(miR-21)is related to hypertension and cardiac *** atrium(LA)dilation is highly sensitive to small haemodynamic changes in the left ventricle(LV)that are induced by *** study aimed to elucidate the relationship between miR-21 expression and LA dilation in elderly patients with essential hypertension(EH).METHODS In this cross-sectional study,one hundred elderly patients with EH were recruited for the *** to their left atrium diameters(LADs),the patients were divided into the LA dilation group[42 patients(42%)]and the no-LA dilation group[58 patients(58%)].The serum levels of miR-21 and chemical biomarkers used in the clinic,such as creatinine,blood urea nitrogen,uric acid,fasting blood glucose,total cholesterol(TC),triglyceride(TG),high-density lipoprotein cholesterol(HDLC),low-density lipoprotein cholesterol(LDL-C),very-low-density lipoprotein cholesterol,Lp(a),apolipoprotein A1(apoA1),and apolipoprotein B,were *** the patients underwent echocardiographic examination,and the LAD,interventricular septum(IVS),right atrium diameter(RAD),right ventricle diameter(RVD),left ventricular end-systolic diameter(LVESD),left ventricular end-systolic diameter(LVEDD)and left ventricular ejection fraction(LVEF)were *** The levels of miR-21[8.02(5.21,14.39)vs.6.05(3.81,8.95),P=0.011]and LVEF(67.02±3.82 vs.64.14±4.43,P=0.001)were higher in the LA dilation *** levels of creatinine[70.40(64.45,80.15)vs.63.9(60.1,73.43)],P=0.020]were higher in the no-LA dilation *** levels of HDLC(r=-0.209,P=0.037),apoA1(r=-0.269,P=0.007)and RAD(r=0.203,P=0.043)were significantly correlated with miR-21 *** LAD was significantly correlated with the RAD(r=0.287,P=0.004),RVD(r=0.450,P<0.001),LVEDD(r=0.248,P=0.013)and LVEF(r=0.232,P=0.020).Multivariate logistic regression revealed that miR-21 significantly influenced LA dilation in elderly patients with EH(P<0.05).CONCLUSIONS Circulating serum levels o

关键词： patients hypertension atrium

Fuzzy-Model-Based Finite Frequency Fault Detection Filtering Design for Two-Dimensional Nonlinear Systems

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IEEE/CAA Journal of Automatica Sinica 2024年第10期11卷 2099-2110页

作者： Meng wang Huaicheng yan Jianbin qiu Wenqiang Ji Key Laboratory of Smart Manufacturing in Energy Chemical Process Ministry of EducationSchool of Information Science and EngineeringEast China University of Science and TechnologyShanghai 200237China Research Institute of Intelligent Control and Systems School of AstronauticsHarbin Institute of TechnologyHarbin 150080China School of Artificial Intelligence Hebei University of TechnologyTianjin 300401China IEEE

This article studies the fault detection filtering design problem for Roesser type two-dimensional(2-D)nonlinear systems described by uncertain 2-D Takagi-Sugeno(T-S)fuzzy ***,fuzzy Lyapunov functions are constructed and the 2-D Fourier transform is exploited,based on which a finite frequency fault detection filtering design method is proposed such that a residual signal is generated with robustness to external disturbances and sensitivity to *** has been shown that the utilization of available frequency spectrum information of faults and disturbances makes the proposed filtering design method more general and less conservative compared with a conventional nonfrequency based filtering design ***,with the proposed evaluation function and its threshold,a novel mixed finite frequency H_(∞)/H_(-)fault detection algorithm is developed,based on which the fault can be immediately detected once the evaluation function exceeds the ***,it is verified with simulation studies that the proposed method is effective and less conservative than conventional non-frequency and/or common Lyapunov function based filtering design methods.

关键词： Fault diagnosis finite frequency specifications mixed H_(∞)/H_(-)performance two-dimensional nonlinear systems

Robust-augmentation nonlinear dynamic inversion control of over-actuated coaxial high-speed helicopter in transition mode

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Chinese Journal of Aeronautics 2024年第8期37卷 404-420页

作者： Yuqing qiu yan LI Jinxi LANG Yuxian LIU Zhong wang School of Automation Northwestern Polytechnical UniversityXi’an 710129China

As the elevator and rudder can be used actively for control,in addition to the rotors,Coaxial High-speed Helicopters(CHHs)have the problems of control redundancy and changing control authority in the transition *** paper presents a robust-augmentation transitioning flight control design for a CHH under the adverse conditions of parametric uncertainties and external ***,based on control characteristic analysis,an Adaptive Filtered Nonlinear Dynamic Inversion(AFNDI)controller is proposed for the angular rate to handle the effect of unknown unstructured uncertainties and external *** analysis proves that the presented angular rate controller can guarantee steady-state and transient ***,the attitude angle and velocity controllers are also ***,an Incremental-based Nonlinear Prioritizing Control Allocation(INPCA)method is designed to take into account control surface transition and changing control authority,which efficiently distributes the required moments between coaxial rotors and aero-surfaces,and avoids the control reversal problem of the yaw *** the proposed control architecture,the low-pass filter is introduced to alleviate the adverse influence of time delay and measurement ***,the effectiveness of the proposed controller is demonstrated through nonlinear numerical simulations,and is compared with existing *** results show that the proposed control law can improve both capabilities of disturbance rejection and fast response,and works satisfactorily for the CHH transitioning control characteristic.

关键词： Coaxial high-speed helicopter Transition mode Attitude control Control allocation Robust adaptive control

Effect on serum metabolomics of rats with premature ovarian insufficiency by Zhibian(BL54) through Shuidao(ST28) acupuncture

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Journal of Traditional Chinese Medicine 2024年第4期44卷 722-733页

作者： yan Jing FENG Huimin qiu Fang wang Haijun YIN Luyun JIN Xiaofei ZHAO Jiyu wang Hongyang yan Xiaoqin Second Clinical College of Shanxi University of Traditional Chinese Medicine Jinzhong 030619China Research Center of Experimental Acupuncture Science Tianjin University of Traditional Chinese MedicineTianjin 301617China Department of Cervical and Lumbar Vertebral Diseases Jinzhong Hospital Affiliated to Shanxi University of Traditional Chinese MedicineJinzhong 030600China

OBJECTIVE:To analyze the serum metabolic targets of the"Zhibian(BL54)through Shuidao(ST28)"acupuncture technique in cyclophosphamide(CTX)-induced premature ovarian insufficiency(POI)model rats and to elucidate the potential molecular mechanism of acupuncture in improving ***:We used an intraperitoneal injection of CTX to establish the POI rat model(POI group)and compared serum hormone levels and ovarian histopathological changes to evaluate the effect of the Zhibian(BL54)through Shuidao(ST28)technique(ZS+POI group)on ovarian ***,nontargeted metabolomics was performed using rat serum by ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF/MS).RESULTS:After acupuncture intervention,the serum hormone levels and ovarian pathological morphology of POI rats were effectively ***,UPLC-Q-TOF/MS results showed that the ZS+POI group showed a significant reversal of the levels of 6 differential *** them,the levels of four serum metabolic markers,divanillyltetrahydrofuran ferulate,trans-ferulic acid,tryptamine,and neuraminic acid,increased *** analysis of biological effects showed that all metabolites were involved in the regulation of reproductive hormone levels and antioxidant and antiapoptotic ***:The"Zhibian(BL54)through Shuidao(ST28)"acupuncture method may improve the ovarian function of POI rats by regulating serum metabolite markers to exert antioxidant and antiapoptotic effects,which provides a theoretical basis for the clinical application of acupuncture in the treatment of POI.

关键词： acupuncture premature ovarian insufficiency metabolomics ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry Zhibian(BL54)through Shuidao(ST28)

Understanding livelihood vulnerability:a perspective from Western Sichuan’s ethnic rural settings

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Journal of Mountain Science 2024年第2期21卷 380-396页

作者： YU Yongqian JING Zheng wang yan qiu Xiaoping yanG Xueting XU Yun School of Geography and Resource Science Sichuan Normal UniversityChengdu 610101China Key Laboratory of land Resources Evaluation and Monitoring in Southwest Ministry of EducationSichuan Normal UniversityChengdu 610101China Sichuan County Economic Development Research Center Mianyang Normal UniversityMianyang 621000China Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China

To explore the livelihood status and key influencing factors of rural households in the minority areas,we collected flat data from 284 rural households in 32 villages across 12 counties of Western Sichuan from 2021 to *** conducted participatory household survey on the livelihood status of the rural households and try to identify the key factors to influence their livelihood vulnerability using multiple linear *** results showed that:the livelihood situation of the rural households is relatively *** vulnerability varies significantly with the income levels,education levels,and income *** vulnerability of farm households,categorized from low to high livelihood types,follows the sequence:non-agricultural dominant households,non-agricultural households,agricultural dominant households,and pure agricultural *** degree of damage to the natural environment,education costs,loan opportunities,the proportion of agricultural income to annual household income,and the presence of sick people in the household have significant positive effects on the livelihood vulnerability index(LVI)of rural households;while help from relatives and friends,net income per capita,household size,household education,agricultural land area,participation in industrial organizations,number of livestock,purchase of commercial houses,drinking water source,and self-supply of food have significant negative *** on the findings,we believe that local rural households operate in a complex livelihood system and recommend continuous interventions targeting key influences to provide empirical research support for areas facing similar situations.

关键词： Livelihood Vulnerability Rural households Ethnic areas

Effect of Mn content on microstructure and properties of AlCrCuFeMnx high-entropy alloy

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China Foundry 2024年第2期21卷 147-158页

作者： Ning wang Kai Ma qiu-da Li Yu-dong Yuan yan-chun Zhao Li Feng School of Materials Science and Engineering Lanzhou University of TechnologyLanzhou 730050China State Key Laboratory of Advanced Processing and Reuse of Nonferrous Metals Lanzhou 730050China CNNC Nuclear Power Operation and Management Co. Ltd.Haiyan 314300ZhejiangChina

AlCrCuFeMnx(x=0,0.5,1,1.5,and 2)high-entropy alloys were prepared using the vacuum arc melting *** microstructure and mechanical properties of AlCrCuFeMnxwere analyzed and tested by XRD,SEM,TEM,nanoindentation,and electronic universal *** results indicate that the AlCrCuFeMnxhigh-entropy alloy exhibits a dendritic structure,consisting of dendrites with a BCC structure,interdendrite regions with an FCC structure,and precipitates with an ordered BCC structure that form within the ***(Mn)has a strong affinity for dendritic,interdendritic,and precipitate structures,allowing it to easily enter these *** an increase in Mn content,the size of the precipitated nanoparticles in the dendritic region initially increases and then ***,the area fraction initially decreases and then ***,the alloy’s strength and wear resistance decrease,while its plasticity *** Al Cr Cu Fe Mn1.5alloy boasts excellent mechanical properties,including a hardness of 360 HV and a wear rate of 2.4×10^(-5)mm^(3)·N^(-1)·mm^(-1).It also exhibits impressive yield strength,compressive strength,and deformation rates of 960 MPa,1,700 MPa,and 27.5%,respectively.

关键词： high-entropy alloys microstructure mechanical properties wear resistance strengthening mechanisms

Model-driven path planning for robotic plasma cutting of branch pipe with single Y-groove based on pipe-rotating scheme

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Advances in Manufacturing 2024年第1期12卷 94-107页

作者： yan Liu qiu Tang Xin-Cheng Tian School of Control Science and Engineering Shandong UniversityJinan250061People’s Republic of China Engineering Research Center of Intelligent Unmanned System Ministry of EducationJinan250061People’s Republic of China School of Mechanical and Electronic Engineering Shandong Jianzhu UniversityJinan250101People’s Republic of China

The automatic cutting of intersecting pipes is a challenging task in *** improved automation and accuracy,this paper proposes a model-driven path planning approach for the robotic plasma cutting of a branch pipe with a single ***,it summarizes the intersection forms and introduces a dual-pipe intersection *** on this model,the moving three-plane structure(a description unit of the geometric characteristics of the intersecting curve)is constructed,and a geometric model of the branch pipe with a single Y-groove is ***,a novel mathematical model for plasma radius and taper compensation is ***,the compensation model and groove model are integrated by establishing movable ***,to prevent collisions between the plasma torch and workpiece,the torch height is planned and a branch pipe-rotating scheme is *** the established models and moving frames,the planned path description of cutting robot is provided in this novel *** accuracy of the proposed method is verified by simulations and robotic cutting experiments.

关键词： Automatic groove cutting of intersecting pipes Model-driven robot path planning Plasma beam radius and taper compensation