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A discrete PI fault observer design and application in variable speed wind turbine system

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High Technology Letters 2009年第4期15卷 434-439页

作者：陈勇旗 Chen qijun Department of Control Science and Engineering Tongji University Shanghai 201804 P.R. China College of Science and Technology. Ningbo University Ningbo 315211 P.R. China

For the discrete-time system which is subjected to uncoupled actuator faults and sensor faults simultaneously,a robust fault diagnosis method based on a proportional integral observer (PIO) is *** proposed PIO uses an additionally introduced integral term of the output errors to obtain the estimationof actuator faults. Besides, the sensor faults are regarded as the augment states so that the PIO cantrace them. Moreover, the convergence of the PIO is proved. A variable speed wind turbine(VWT) exampleis given to demonstrate the fast convergence and diagnosis precision of the proposed PIO.

关键词： fault diagnosis discrete-time systems proportional integral observer(PIO)

静电纺聚酰胺6/聚苯乙烯复合纳米纤维膜制备及其空气过滤性能

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纺织学报 2024年第1期45卷 56-64页

作者：陈江萍郭朝阳张琪骏吴仁香钟鹭斌郑煜铭中国科学院城市环境研究所中国科学院区域大气环境研究卓越创新中心福建厦门361021 中国科学院城市环境研究所中国科学院城市污染物转化重点实验室福建厦门361021 中国科学院大学北京100049 福建省大气臭氧污染防控重点实验室福建厦门361021

针对空气过滤纤维材料的过滤效率、阻力和使用寿命难以平衡的问题,采用多喷头静电纺丝技术,制备了不同直径、形貌纤维及不同纤维沉积顺序的聚酰胺6/聚苯乙烯(PA6/PS)复合纳米纤维膜,测试了复合膜的平均孔径及孔隙率,建立了纤维结构与过... 详细信息

针对空气过滤纤维材料的过滤效率、阻力和使用寿命难以平衡的问题,采用多喷头静电纺丝技术,制备了不同直径、形貌纤维及不同纤维沉积顺序的聚酰胺6/聚苯乙烯(PA6/PS)复合纳米纤维膜,测试了复合膜的平均孔径及孔隙率,建立了纤维结构与过滤效率及阻力的构效关系;结合扫描电镜表征探讨了不同形貌、直径纤维的叠加次序对过滤寿命及细颗粒物沉积行为的影响,系统研究了过滤风速、细颗粒物尺寸对过滤性能的影响。结果表明:在5.33 cm/s的风速下,以多喷头静电纺丝方式制备的PA6/PS复合膜具有更好的抵抗风速变化的能力,在长期使用中阻力增加较缓慢,其具有93.13%的过滤效率,30.67 Pa的过滤阻力和0.0889 Pa-1的品质因子,综合过滤性能优于同等条件下H10等级(过滤效率>90%)的商业玻璃纤维过滤膜。

关键词：聚酰胺6 聚苯乙烯多喷头静电纺丝空气过滤多层复合滤料微纳米纤维串珠结构

Passive dynamic model for walking down stairs 25th

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Passive dynamic model for walking down stairs

Aerodynamic and structural characteristics of helicopter rotor in circling flight

第2.届中国控制与决策会议

作者： Kang An qijun Chen Robotics and Intelligent System Laboratory Tongji University

ISBN: (纸本)9781467355322

This paper presents a passive dynamic walking model that can walk down stairs. Knee-bend mechanism which is inspired from the pattern of human’s walking down stairs is designed in the walking model. The stance knee is designed to be bent between knee-strike and heel-strike. The bending time of the stance leg after knee-strike is adjusted to adapt to the stair height. By traversing the bending time of the stance leg, the stable walking motion with a certain stair height could be found. The force at the stance foot and the eigenvalues of the Jacobian are analyzed to verify the walking motion. The results show that the periodic walking motion is stable when the stair height is less than 0.11. Furthermore, the features of the walking motion with different stair height are discussed.

关键词： Biped locomotion Passive dynamic walking Knee-bend Stair

来源： cnki会议评论

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Chinese Journal of Aeronautics 2023年第12期36卷 282-296页

作者： Xu ZHOU Xiayang ZHANG Bo WANG qijun ZHAO National Key Laboratory of Helicopter Aeromechanics Nanjing University of Aeronautics and AstronauticsNanjing 210016China

To investigate the distinct properties of the helicopter rotors during circling flight,the aerodynamic and dynamic models for the main rotor are established considering the trim conditions and the flight parameters of *** free wake method is introduced to compute the unsteady aerodynamic loads of the rotor characterized by distortions of rotor wakes,and the modal superposition method is used to predict the overall structural loads of the *** effectiveness of the aerodynamic and the structural methods is verified by comparison with the experimental results,whereby the influences of circling direction,radius,and velocity are evaluated in both aerodynamic and dynamic *** results demonstrate that the circling condition makes a great difference to the performance of rotor vortex,as well as the unsteady aerodynamic *** the decrease of the circling radius or the increment of the circling velocity,the thrust of the main rotor increases apparently to balance the inertial ***,the harmonics of aerodynamic loads in rotor disc change severely and an evident aerodynamic load shock appears at high-order components,which further causes a shift-of-peak-phase bending moment in the flap ***,the advancing side of blade experiences second blade/vortex interaction,whose intensity has a distinct enhancement as the circling radius decreases with the motion of vortexes.

关键词： Aerodynamic load Circling state Free wake method Modal superposition method Structural load

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基于粘附动力学模型的助航灯去污机理及实验

低温工程 2024年第1期 45-52页

作者：董慧芬王俊峰董子正罗其俊中国民航大学电子信息与自动化学院天津300300 北京飞机维修工程有限公司天津分公司天津300300

针对嵌入式助航灯具发光表面的常见污染物去除问题,提出一种基于污染物颗粒的粘附动力学模型和干冰颗粒滑动分离模型的干冰清洗机理分析方法。通过分析不同的污染物在发光口透镜表面的粘附动力学模型,建立污染物颗粒滑动分离模型,确定... 详细信息

针对嵌入式助航灯具发光表面的常见污染物去除问题,提出一种基于污染物颗粒的粘附动力学模型和干冰颗粒滑动分离模型的干冰清洗机理分析方法。通过分析不同的污染物在发光口透镜表面的粘附动力学模型,建立污染物颗粒滑动分离模型,确定颗粒去除的临界分离速度,并通过有限元分析干冰颗粒的速度场分布,进而研究面向特定不同污染物去污机理及去污清洗参数对清洗效果的影响,并在此基础上进行了实验验证。实验结果表明,设定不同清洗参数在达到相同清洗效果的清洁度情况下,去除灰尘的干冰消耗量为0.01 L,去除油污的干冰消耗量为0.015 L,去除胶痕的干冰消耗量为0.105 L。在清洗效果得到保证的前提下,确定了不同污染物的清洗参数。

关键词：助航灯具干冰清洗动力学模型去污机理清洗参数

Structural Parameter Analyses on Rotor Airloads with New Type Blade-Tip Based on CFD/CSD Coupling Method

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Transactions of Nanjing University of Aeronautics and Astronautics 2016年第6期33卷 -页

作者： Wang Junyi Zhao qijun Ma Li National Key Laboratory of Science and Technology on Rotorcraft Aeromechanics Nanjing University of Aeronautics and Astronautics

For accurate aeroelastic analysis,the unsteady rotor flowfield is solved by computational fluid dynamics(CFD)module based on RANS/Euler equations and moving-embedded grid system,while computational structural dynamics(CSD)module is introduced to handle blade *** CFD module,dual time-stepping algorithm is employed in temporal discretization,Jameson two-order central difference(JST)scheme is adopted in spatial discretization and B-L turbulent model is used to illustrate the viscous *** CSD module is developed based on Hamilton′s variational principles and moderate deflection beam *** deformation is implemented using algebraic method through coordinate transformations to achieve deflections with high quality and efficiency.A CFD/CSD loose coupling strategy is developed to transfer information between rotor flowfield and blade *** CFD and the CSD modules are verified *** the CFD/CSD loose coupling is adopted in airloads prediction of UH-60A rotor under high speed forward flight *** calculated results agree well with test ***,effects of torsional stiffness properties on airloads of rotors with different tip swept angles(from 10° forward to 30° backward)are *** results are evaluated through pressure distribution and airloads variation,and some meaningful conclusions are drawn the moderated shock wave strength and pressure gradient caused by varied tip swept angle and structural properties.

关键词： rotor airloads structural parameter computational fluid dynamics(CFD) computational structural dynamics(CSD) loose coupling method

面向高危场景的医疗救援型防暴车艺工融合设计研究

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设计 2024年第18期37卷 101-104页

作者：李泽珩刘华段齐骏南京理工大学设计艺术与传媒学院

为辅助医疗救援型防暴车设计,提高车辆美观度和实用性,文中进行了面向高危场景的医疗救援型防暴车艺工融合设计研究。梳理防暴车辆设计研究现状;分析高危场景下的医疗救援任务和医疗救援型防暴车辆用户需求;从造型与情感化设计(艺)、功... 详细信息

为辅助医疗救援型防暴车设计,提高车辆美观度和实用性,文中进行了面向高危场景的医疗救援型防暴车艺工融合设计研究。梳理防暴车辆设计研究现状;分析高危场景下的医疗救援任务和医疗救援型防暴车辆用户需求;从造型与情感化设计(艺)、功能与交互设计(工)两个角度探讨面向高危场景的医疗救援型防暴车设计策略。得出了医疗救援型防暴车艺工融合设计策略,以某型号医疗救援型防暴车的内外饰设计为例对研究得出的设计策略进行了验证。证明了该设计策略具有一定的可行性和实用性,能够为医疗救援型防暴车辆创新设计提供有效指导。

关键词：高危场景医疗救援防暴车艺工融合汽车设计

维普期刊数据库博看期刊

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颈外动脉支架置入术后特发性三叉神经痛一例

中国脑血管病杂志 2024年第8期21卷 537-540页

作者：何建霄李薪阳孙起军毛明利首都医科大学燕京医学院北京101300 首都医科大学密云教学医院神经外科

三叉神经痛(TN)是临床中较为常见的神经系统疾病,常给患者带来难以忍受的疼痛。作者报道1例颈外动脉支架置入术后发生特发性TN患者的诊治经过并分析其疼痛病因,考虑与上颌动脉血流改善后压迫冲击三叉神经有关。应用卡马西平治疗后患者T... 详细信息

三叉神经痛(TN)是临床中较为常见的神经系统疾病,常给患者带来难以忍受的疼痛。作者报道1例颈外动脉支架置入术后发生特发性TN患者的诊治经过并分析其疼痛病因,考虑与上颌动脉血流改善后压迫冲击三叉神经有关。应用卡马西平治疗后患者TN有效缓解,出院1周后随访未诉其他不适,TN控制良好。国内外尚未见相关报道,故报道该病例供临床医师参考与讨论。

关键词：颈外动脉狭窄颈动脉支架置入术三叉神经痛治疗

Active Balance Control of Humanoid Locomotion Based on Foot Position Compensation

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Journal of Bionic Engineering 2020年第1期17卷 134-147页

作者： Chengju Liu Tong Zhang Ming Liu qijun Chen School of Electronics and Information Engineering Tongji UniversityShanghai 201804China School of Electronic and Computer Engineering Hong Kong University of Science and TechnologyHong Kong 999077China

A foot positioning compensator is developed in this paper for a full-body humanoid to retrieve its balance during continuous *** online Foot Position Compensator(FPC)is designed to improve the robustness of biped walking,which can modify predefined step position and step duration online with sensory *** placement parameters are learned by the FPC based on the Policy Gradient Reinforcement Learning(PGRL)***,the FPC assists the humanoid robot in rejecting external disturbances and recovering the walking position by re-planning the trajectories of walking pattern and the Center of Mass(CoM).An upper body pose control strategy is also presented to further enhance the performance of humanoid robots to overcome strong external *** advantages of this proposed method are that it neither requires prior information about the walking terrain conditions,nor relies on range sensor information for surface topology *** effectiveness of the proposed method is verified via Webots simulation and real experiments on a full-body humanoid NAO robot.

关键词： humanoid walking active balance Foot Positioning Compensation(FPC) Policy Gradient Reinforcement Learning(PGRL)