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Topological and Shape Optimization of Flexure Hinges for Designing Compliant Mechanisms Using the Level Set Method
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作者 Benliang Zhu Xianmin Zhang +2 位作者 Min Liu Qi Chen Hai Li 《中国机械工程学报:英文版》 SCIE EI CAS CSCD 2019年第1期42-53,共12页
A flexure hinge is a major component in designing compliant mechanisms that o ers unique possibilities in a wide range of application fields in which high positioning accuracy is required. Although various flexure hin... A flexure hinge is a major component in designing compliant mechanisms that o ers unique possibilities in a wide range of application fields in which high positioning accuracy is required. Although various flexure hinges with di erent configurations have been successively proposed, they are often designed based on designers’ experiences and inspirations. This study presents a systematic method for topological optimization of flexure hinges by using the level set method. Optimization formulations are developed by considering the functional requirements and geometrical constraints of flexure hinges. The functional requirements are first constructed by maximizing the compliance in the desired direction while minimizing the compliances in the other directions. The weighting sum method is used to construct an objective function in which a self-adjust method is used to set the weighting factors. A constraint on the symmetry of the obtained configuration is developed. Several numerical examples are presented to demonstrate the validity of the proposed method. The obtained results reveal that the design of a flexure hinge starting from the topology level can yield more choices for compliant mechanism design and obtain better designs that achieve higher performance. 展开更多
关键词 TOPOLOGY optimization Compliant MECHANISMS Flexure HINGES Level set METHOD
Direct numerical simulation of turbulent boundary layer over an anisotropic compliant wall 预览
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作者 Qian-Jin Xia Wei-Xi Huang Chun-Xiao Xu 《力学学报:英文版》 SCIE EI CAS CSCD 2019年第2期384-400,共17页
Direct numerical simulation of a spatially developing turbulent boundary layer over a compliant wall with anisotropic wall material properties is performed. The Reynolds number varies from 300 to approximately 860 alo... Direct numerical simulation of a spatially developing turbulent boundary layer over a compliant wall with anisotropic wall material properties is performed. The Reynolds number varies from 300 to approximately 860 along the streamwise direction, based on the external flow velocity and the momentum thickness. Eight typical cases are selected for numerical investigation under the guidance of the monoharmonic analysis. The instantaneous flow fields exhibit the traveling wavy motion of the compliant wall, and the frequency-wavenumber power spectrum of wall pressure fluctuation is computed to quantify the mutual influence of the wall compliance and the turbulent flow at different wave numbers. It is shown that the Reynolds shear stress and the pressure fluctuation are generally enhanced by the wall compliance with the parameters considered in the present study. A dynamical decomposition of the skin-friction coefficient is derived, and a new term (CW) appears due to the wall-induced Reynolds shear stress. The influence of the anisotropic compliant wall motion on the turbulent boundary layer through the wall-induced negative Reynolds shear stress is discussed. To elucidate the underlying mechanism, the budget analysis of the Reynolds stresses transportation is further carried out. The impact of the wall compliance on the turbulent flow is disclosed by examining the variations of the diffusion and velocity-pressure correlation terms. It is shown that increase of the Reynolds stresses inside the flow domain is caused by enhancement of the velocity-pressure correlation term, possibly through the long-range influence of the wall compliance on the pressure field, rather than diffusion of the wall-induced Reynolds shear stress into the fluid flow. 展开更多
关键词 TURBULENT boundary layer ANISOTROPIC compliant WALL Direct numerical simulation Skin-friction coefficient REYNOLDS shear stress
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Design concept development of a variable magnetization motorwith improved efficiency and controllable stiffness for roboticapplications
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作者 BAI Kun ZHU Lang +1 位作者 YUAN Mi LEE Kok-Meng 《中国科学:技术科学英文版》 SCIE EI CAS CSCD 2019年第1期39-46,共8页
A variable magnetization(VM) motor by incorporating magnets that can be flexibly configured with variable magnetization process is proposed to meet the emerging requirements on motor efficiency and actuator compliance... A variable magnetization(VM) motor by incorporating magnets that can be flexibly configured with variable magnetization process is proposed to meet the emerging requirements on motor efficiency and actuator compliance in robotic applications. A generalized spin torque model is established which provides a relationship between the motor torque and two different types of motor inputs, the current inputs and the magnet magnetizations. Avariable magnetization process is proposed based on the study of the hysteresis properties of the magnetic materials and the design criteria for implementing the variable magnetization process with current pulses are established. The feasibility of the variable magnetization is validated with experimental data and the motor functions and performances are numerically demonstrated and evaluated. The results show that the VM motor can maintain high efficiency by switching between two actuation modes. Controllable stiffness at different equilibria can be also achieved with the VM motor with instantaneous magnetizing current pulses. 展开更多
关键词 compliant actuators DIRECT-DRIVE motors VARIABLE STIFFNESS motors VARIABLE MAGNETIZATION motors
Response surface methodology-based hybrid robust design optimization for complex product under mixed uncertainties 预览
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作者 WAN Liangqi CHEN Hongzhuan OUYANG Linhan 《系统工程与电子技术:英文版》 SCIE EI CSCD 2019年第2期308-318,共11页
Minimizing the impact of the mixed uncertainties(i.e.,the aleatory uncertainty and the epistemic uncertainty) for a complex product of compliant mechanism(CPCM) quality improvement signifies a fascinating research top... Minimizing the impact of the mixed uncertainties(i.e.,the aleatory uncertainty and the epistemic uncertainty) for a complex product of compliant mechanism(CPCM) quality improvement signifies a fascinating research topic to enhance the robustness.However, most of the existing works in the CPCM robust design optimization neglect the mixed uncertainties, which might result in an unstable design or even an infeasible design. To solve this issue, a response surface methodology-based hybrid robust design optimization(RSM-based HRDO) approach is proposed to improve the robustness of the quality characteristic for the CPCM via considering the mixed uncertainties in the robust design optimization. A bridge-type amplification mechanism is used to manifest the effectiveness of the proposed approach. The comparison results prove that the proposed approach can not only keep its superiority in the robustness, but also provide a robust scheme for optimizing the design parameters. 展开更多
关键词 response surface METHODOLOGY (RSM) HYBRID robust design optimization (HRDO) UNCERTAINTY complex product of compliant mechanism (CPCM)
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Dimensional Variation Modeling of Aircraft Compliant Part Assembly Considering Clamping Force Change 预览
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作者 TAN Changbai ZHANG Wei WANG Zhiguo 《南京航空航天大学学报:英文版》 EI CSCD 2019年第2期298-305,共8页
Compliant parts are widely applied to aircraft structures.Due to the ease of deformation of compliant parts in assembly,the prediction of assembly variation is especially important for assembly quality control.A dimen... Compliant parts are widely applied to aircraft structures.Due to the ease of deformation of compliant parts in assembly,the prediction of assembly variation is especially important for assembly quality control.A dimensional variation model considering the clamping force change in assembly is proposed based on the method of influence coefficient(MIC).First,the assembly process is decomposed into several steps including positioning,clamping,joining,and spring-back.Then,the force-displacement relationship is formulated according to the varied force conditions on the parts in each assembly step.Finally,two examples are illustrated to validate the proposed assembly variation model.The results show the impact of clamping force change is significant on the assembly variation,and the proposed model can predict the assembly variation more accurately than the referred method without clamping force correction at the over-constrained locating points of fixture. 展开更多
关键词 AIRCRAFT dimensional variation compliant parts CLAMPING force CHANGE method of influence coefficient(MIC)
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Torsional negative stiffness mechanism by thin strips 预览
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作者 Jinyou Li Kangjia Fu +1 位作者 Yongpeng Gu Zhihua Zhao 《力学快报:英文版》 CAS CSCD 2019年第3期206-211,共6页
Negative stiffness mechanisms have great application potential in different fields, such as vibration isolation, energy absorption and mesh antenna unfolding. Although numerous compliant mechanisms with negative stiff... Negative stiffness mechanisms have great application potential in different fields, such as vibration isolation, energy absorption and mesh antenna unfolding. Although numerous compliant mechanisms with negative stiffness features have been implemented in literature, the designing work remains in its infancy, and proposing an original design strategy may open a new avenue for the future inventions. In this study, inspired by a toy, we developed a novel type of compliant mechanism composed of thin strips, possessing negative stiffness property under torsion. The negative stiffness feature is achieved by large deformation of the strips rather than mechanical buckling. As a consequence, the obtained negative stiffness segment covers a significantly long range. Demonstrated with examples, it was shown that the proposed mechanisms could be combined with other compliant mechanisms to realize long-range unusual torque-angle relationships, which can be used in different applications. 展开更多
关键词 NEGATIVE STIFFNESS Compliant MECHANISM STRIP Torsional SPRING Flexible MULTIBODY system
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Robust topology optimization of hinge-free compliant mechanisms with material uncertainties based on a non-probabilistic field model
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作者 Junjie ZHAN Yangjun LUO 《机械工程前沿:英文版》 CSCD 2019年第2期201-212,共12页
This paper presents a new robust topology optimization framework for hinge-free compliant mechanisms with spatially varying material uncertainties,which are described using a non-probabilistic bounded field model.Boun... This paper presents a new robust topology optimization framework for hinge-free compliant mechanisms with spatially varying material uncertainties,which are described using a non-probabilistic bounded field model.Bounded field uncertainties are efficiently represented by a reduced set of uncertain-but-bouncled coeflficients on the basis of the series expansion method.Robust topology optimization of compliant mechanisms is then defined to minimize the variation in output displacement under constraints of the mean displacement and predefined material volume.The nest optimization problem is solved using a gradient-based optimization algorithm.Numerical examples are presented to illustrate the effectiveness of the proposed method for circumventing hinges in topology optimization of compliant mechanisms. 展开更多
关键词 compliant mechanisms ROBUST topology optimization HINGES uncertainty BOUNDED field
基于磁流变技术的非球面柔顺数控研抛工具研究
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作者 白冰 《机械设计与制造》 北大核心 2018年第12期164-167,共4页
针对目前磁流变抛光成本高、抛光力控制复杂的问题,开发了一种新的基于磁流变技术的非球面柔顺数控研抛工具系统,由磁流变阻尼器(MRD)控制研抛过程中的研抛力,由数控车床控制研抛工具位置。介绍了工具系统的组成,阐明了基于MRD的研抛... 针对目前磁流变抛光成本高、抛光力控制复杂的问题,开发了一种新的基于磁流变技术的非球面柔顺数控研抛工具系统,由磁流变阻尼器(MRD)控制研抛过程中的研抛力,由数控车床控制研抛工具位置。介绍了工具系统的组成,阐明了基于MRD的研抛原理,分析了研抛工具与非球面工件之间的接触力及其动态传递过程,建立了研抛力模型和工具系统动态模型,并进行了参数辨识和仿真研究,得到了系统的传递函数的和PID控制器的相关参数,最后进行了系统动态性能和研抛实验验证,实验结果表明,开发的研抛工具系统,具有较好的响应特性,可以实时控制研抛过程中的研抛力,可获得表面粗糙度Ra=0.028μm的非球面镜面表面。 展开更多
关键词 磁流变 非球面 柔顺 研抛工具 研抛力 动态模型
全文增补中
创建“4+X”标准体系 推动政务投诉办理工作转型升级——青岛市城阳区民声服务办理工作标准化建设的实践(英文)
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作者 张海涛 李玲 丁磊 《中国标准化:英文版》 2016年第1期46-51,共6页
<正>Standardized process of public complaints,applied in Qingdao,Shandong Province,was approved as a provincial pilot project on service standardization in January 2015.Chengyang District of the city has taken s... <正>Standardized process of public complaints,applied in Qingdao,Shandong Province,was approved as a provincial pilot project on service standardization in January 2015.Chengyang District of the city has taken standardization as the main guiding principle for public complaint service,and integrated the ideas of standards in the major processes of compliant handling from personnel training,operation,complaint analysis and diagnosis. 展开更多
关键词 工作标准化 COMPLAINT compliant PROVINCIAL Qingdao SHANDONG DISTRICT approved handling DISTRICT
互操作、互理解、互遵循——军事信息系统的新型能力目标与评估模型 预览 被引量:11
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作者 曹江 高岚岚 《指挥与控制学报》 2015年第1期41-45,共5页
针对军队信息化转型以及信息系统发展与运用现状,提出军事信息系统的新型能力目标,具体分析了“互操作、互理解、互遵循”概念和内涵,构建了新型能力模型,用以规范未来军事信息系统的能力目标,适应新技术、新模式和新需求的挑战,... 针对军队信息化转型以及信息系统发展与运用现状,提出军事信息系统的新型能力目标,具体分析了“互操作、互理解、互遵循”概念和内涵,构建了新型能力模型,用以规范未来军事信息系统的能力目标,适应新技术、新模式和新需求的挑战,进而加速推进军队信息化建设进程. 展开更多
关键词 互操作 互理解 互遵循 信息系统
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无心而顺性与习以成性——郭象玄学意义的功夫论刍议 预览
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作者 刘晨 《学术探索》 CSSCI 北大核心 2015年第8期1-6,共6页
在郭象的玄学体系中,一方面强调独化自性,强调万物的差异性和性之不可变,另一方面也不否定后天的练习对成就性的作用,这就是郭象以独化论为基础的功夫论。独化即是要顺性而化,人要做到顺性而化则要无心,这既是从万物存在的本体论... 在郭象的玄学体系中,一方面强调独化自性,强调万物的差异性和性之不可变,另一方面也不否定后天的练习对成就性的作用,这就是郭象以独化论为基础的功夫论。独化即是要顺性而化,人要做到顺性而化则要无心,这既是从万物存在的本体论的角度对人的存在方式提出的要求,也是人的应然的存在方式的本体论依据。而如何成就人的独化,就是功夫论所要解决的问题。习以成性并非能够改变人的性,而是通过不断地反复练习,使人达到物我两忘的境界,使性之能能够全然的凸显出来,从而实现人生的逍遥。 展开更多
关键词 独化 无心 顺性 习以成性 功夫论
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违法侦查行为投诉处理机制实务探究-以检察机关法律监督为视角 预览
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作者 粱田 谭金生 肖波 《西南政法大学学报》 2013年第6期127-135,共9页
2012年修改后的《刑事诉讼法》进一步强化了以检察监督为主的违法侦查行为投诉处理模式,使我国违法侦查行为权利救济制度的建立和完善取得了实质性进展和突破。但是,修改后的《刑事诉讼法》对违法侦查行为权利救济的规定仍然比较原则... 2012年修改后的《刑事诉讼法》进一步强化了以检察监督为主的违法侦查行为投诉处理模式,使我国违法侦查行为权利救济制度的建立和完善取得了实质性进展和突破。但是,修改后的《刑事诉讼法》对违法侦查行为权利救济的规定仍然比较原则,为增强实践中的可操作性,有必要进一步细化和完善,特别是在程序设计上要解决好一系列问题,主要包括违法侦查行为投诉主体、受理条件、利害关系人的范围、调查处理方式、侦查机关自我审查程序、违法侦查行为的处置等。 展开更多
关键词 违法侦查行为 投诉 处理机制 检察监督
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大变形柔性转动副结构设计与柔度分析 预览 被引量:6
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作者 杨启志 朱小兵 +3 位作者 马履中 黄国全 庄佳奇 訾鹏飞 《农业机械学报》 EI CAS CSCD 北大核心 2012年第9期209-212,共4页
目前运用较多的柔性运动副基本上只能产生微细变形,适用于微动领域,缺少能产生宏观尺度变形的柔性运动副。在弹性曲板变形理论的基础上设计出一种新型柔性转动副,可以满足宏观尺寸下的变形要求。通过理论分析建立其柔度矩阵,分析其... 目前运用较多的柔性运动副基本上只能产生微细变形,适用于微动领域,缺少能产生宏观尺度变形的柔性运动副。在弹性曲板变形理论的基础上设计出一种新型柔性转动副,可以满足宏观尺寸下的变形要求。通过理论分析建立其柔度矩阵,分析其转动刚度与转动误差,利用Matlab进行了理论计算,并进行了Ansys软件仿真与实体模型试验。结果表明:理论计算与仿真的转动刚度相对误差为5.6%,转动误差相对误差为3.4%,通过试验验证了转动刚度和转动误差相对角度变形的变化规律,说明对该新型大变形柔性转动副的柔度分析正确。 展开更多
关键词 柔性机构 转动副 柔度矩阵 大变形 仿真 试验
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空间对接中柔顺力控制器综合设计 预览
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作者 赵慧 张尚盈 韩俊伟 《液压气动与密封》 2008年第4期 50-54,共5页
研究空间对接中的柔顺力控制;利用基于位置内环柔顺力控制的六自由度并联机器人来模拟空间对接强制校正阶段的推拉过程。介绍了基于位置内环的柔顺力控制结构。详细阐述PID控制器、鲁棒控制器的综合设计方法。仿真和实验结果表明了所... 研究空间对接中的柔顺力控制;利用基于位置内环柔顺力控制的六自由度并联机器人来模拟空间对接强制校正阶段的推拉过程。介绍了基于位置内环的柔顺力控制结构。详细阐述PID控制器、鲁棒控制器的综合设计方法。仿真和实验结果表明了所设计力控制器的有效性以及鲁棒力控制器的优越性。 展开更多
关键词 空间对接 柔顺 力控制 鲁棒
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基于动态博弈描述的电子商务协议公平性 预览
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作者 杨素荣 谭汉松 《计算机应用研究》 CSCD 北大核心 2008年第6期 1789-1792,共4页
基于通信顺序进程和动态博弈理论对电子商务系统建模,提出了结构化的电子商务协议的公平性,并基于该模型给出了公平性的形式化定义,可以用于电子商务协议公平性的分析。与以往工作相比,主要贡献在于:a)系统模型中的失效模型分别对进... 基于通信顺序进程和动态博弈理论对电子商务系统建模,提出了结构化的电子商务协议的公平性,并基于该模型给出了公平性的形式化定义,可以用于电子商务协议公平性的分析。与以往工作相比,主要贡献在于:a)系统模型中的失效模型分别对进程和通信失效建模,增加了通信延迟失效模型,可以分析系统失效时满足的公平性;b)收益平衡从参与者获得利益和损失利益两个角度定义公平性,打破了以往公平性定义只能应用于零和交易系统的局限;c)结构化的公平性分别考虑系统诚实参与者中途自愿退出或者因失效中止协议的公平性和有参与者欺骗下的协议的公平性等。后两点解决了系统满足公平性定义但实际上对参与者不公平的矛盾. 展开更多
关键词 公平性 电子商务协议 博弈 遵守型 撤销型 欺骗型
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一种伞式可折叠柔性变胞机构的设计分析研究 预览 被引量:6
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作者 杨毅 丁希仑 戴建生 《航空学报》 EI CAS CSCD 北大核心 2007年第4期 1014-1017,共4页
柔性变胞机构是一种依靠柔性构件变形实现构态变化的机构,利用柔性机构的某些特性可以综合提高变胞机构的性能和效率。提出一种伞式可折叠柔性变胞机构,该机构综合了变胞机构和柔性机构两大特点。利用伪刚体模型理论对该机构进行拓扑学... 柔性变胞机构是一种依靠柔性构件变形实现构态变化的机构,利用柔性机构的某些特性可以综合提高变胞机构的性能和效率。提出一种伞式可折叠柔性变胞机构,该机构综合了变胞机构和柔性机构两大特点。利用伪刚体模型理论对该机构进行拓扑学,运动学及稳态分析。最后,对该机构进行运动学仿真,结果表明伪刚体模型法适合于柔性变胞机构的分析与设计。 展开更多
关键词 柔性 变胞机构 双稳态 伪刚体
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国外虚假自白研究的进展 预览
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作者 杨伟伟 罗大华 《河南司法警官职业学院学报》 2007年第1期 32-34,共3页
虚假自白是司法心理学研究的重要内容。近十几年来西方虚假自白的研究得到很快的发展。国外虚假自白的分类、实验室中的虚假自白、产生虚假自白的影响因素等方面的研究成果对我国有借鉴意义。了解这些虚假自白的研究进展,借鉴其研究方... 虚假自白是司法心理学研究的重要内容。近十几年来西方虚假自白的研究得到很快的发展。国外虚假自白的分类、实验室中的虚假自白、产生虚假自白的影响因素等方面的研究成果对我国有借鉴意义。了解这些虚假自白的研究进展,借鉴其研究方法和成果,对我国司法心理学的研究有推动促进作用。 展开更多
关键词 虚假自白 服从 内化 审讯策略
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汪母形象的文化意蕴 预览 被引量:1
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作者 杜运通 《韩山师范学院学报》 2006年第2期 44-47,共4页
汪母是中国传统文化的载体。她性格张力场的外在特征是:慈爱的母亲,凶悍的婆婆。命运的奴隶。她时而高尚.时而卑下;时而慈善。时而冷酷;时而坚执.时而脆弱;时而像中国传统的慈母,时而又像西方刁钻的贵妇。她既不是天使,也不是... 汪母是中国传统文化的载体。她性格张力场的外在特征是:慈爱的母亲,凶悍的婆婆。命运的奴隶。她时而高尚.时而卑下;时而慈善。时而冷酷;时而坚执.时而脆弱;时而像中国传统的慈母,时而又像西方刁钻的贵妇。她既不是天使,也不是魔鬼,而是一个包孕着丰厚文化意蕴的“人”。 展开更多
关键词 汪母 慈祥 凶悍 奴隶 文化意蕴
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STABILITY EIGENFUNCTIONS OF A BOUNDARY-LAYER FLOW OVER VISCOELASTIC COMPLIANT WALL 预览
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作者 Zhao, Han-Zhong 《水动力学研究与进展:英文版》 SCIE EI CSCD 2001年第4期48-54,共7页
关键词 boundary layer compliant WALL EIGENFUNCTION Tollmien-Schlichting INSTABILITY (TSI) compliant-induced flow INSTABILITY (CIFI)
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TEMPORAL EIGENVALUE SPECTRA OF BOUNDARY-LAYER FLOW OVER RIGID WALL AND COMPLIANT WALL 预览
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作者 Zhao, H.Z. Yeo, K.S. 《水动力学研究与进展:英文版》 SCIE EI CSCD 2001年第1期70-74,共5页
关键词 boundary layer compliant WALL EIGENVALUE spectrum Tollmien-schlichting INSTABILITY (TSI) Compliance-induced flow INSTABILITY (CIFI)
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