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A reduced order model for coupled mode cascade flutter analysis

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Chinese Journal of Aeronautics 2022年第10期35卷 176-182页

作者： Huang HUANG Xinkai JIA Jia REN bochao cao Dingxi WANG Xiuquan HUANG School of Power and Energy Northwestern Polytechnical UniversityXi'an 710072China Yangtze River Delta Research Institute of Northwestern Polytechnical University Taicang 215400China Department of Aeronautics and Astronautics Fudan UniversityShanghai 200433China

A Reduced Order Model(ROM)based analysis method for turbomachinery cascade coupled mode flutter is presented in this *** unsteady aerodynamic model is established by a system identification technique combined with a set of Aerodynamic Influence Coefficients(AIC).Subsequently,the aerodynamic model is encoded into the state space and then coupled with the structural dynamic equations,resulting in a ROM of the cascade *** cascade flutter can be determined by solving the eigenvalues of the ***-torsional coupled mode flutter analysis for the Standard Configuration Eleven(SC11)cascade is used to validate the proposed method.

关键词： Aerodynamic influence coefficients Chirp signal Coupled mode flutter Eigenvalue problem Reduced order model

基于本征正交分解技术的高效气动弹性耦合计算方法

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空气动力学学报 2018年第5期36卷 743-748页

作者：回庆龙曹博超中航工业沈阳飞机工业(集团)有限公司试飞站辽宁沈阳110850 复旦大学航空航天系上海200433

将降阶非定常涡格法与结构动力学方程耦合,构造出一种高效的气动弹性计算模型。计算模型中通过引入伪时间步迭代实现了气动与结构计算的紧耦合。另外,通过本征正交分解方法实现了计算模型的降阶。作为方法验证,文中将该方法应用于进行... 详细信息

将降阶非定常涡格法与结构动力学方程耦合,构造出一种高效的气动弹性计算模型。计算模型中通过引入伪时间步迭代实现了气动与结构计算的紧耦合。另外,通过本征正交分解方法实现了计算模型的降阶。作为方法验证,文中将该方法应用于进行沉浮振荡运动的柔性薄板的气动弹性计算。计算结果表明,仅通过前7个POD模态就可以对涡格法的全模型进行很好的近似,并且该方法在损失很小精度(约1%)的条件下可以实现计算速度的大幅提升(约10倍)。在本文中,降阶模型在POD分析的样本变化范围内和变化范围外都有很好的表现。

关键词：气动弹性计算降阶方法非定常涡格法

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强化学习方法在翼型拍动实验中的应用

空气动力学学报 2023年第9期41卷 20-29页

作者：张进周雷曹博超复旦大学航天航空系上海200433

将深度强化学习方法应用于水洞实验,实现了实验室内的自动闭环优化框架,并用该框架优化了雷诺数R_(e)=1.3×10^(4)下纯俯仰运动的NACA0012翼型模型的推进效率。现有的相关研究往往将运动模式限制为某种周期性函数,具有局限性。借助于强... 详细信息

将深度强化学习方法应用于水洞实验,实现了实验室内的自动闭环优化框架,并用该框架优化了雷诺数R_(e)=1.3×10^(4)下纯俯仰运动的NACA0012翼型模型的推进效率。现有的相关研究往往将运动模式限制为某种周期性函数,具有局限性。借助于强化学习方法,实现了在更广的非周期动作空间中的动作搜索。在实验中,模型自动地与水洞环境进行交互,最终学习到了高效推进的非周期运动策略。另外,通过修改奖励函数,实现了在给定推力阈值以上的效率优化。研究结果显示,强化学习模型可以在实验过程中通过不断调整拍动动作的幅度和频率来实现推进效率的持续提升,并且最终通过强化学习方法获得的最优拍动动作均与正弦拍动动作接近,得到的最优推进效率基本位于同等幅度正弦动作效率的上边界。研究展示了强化学习方法用于复杂流动控制问题的可行性。

关键词：拍动翼型实验流体力学强化学习机器学习效率优化

Optimizing the key parameter to accelerate the recovery of AMOC under a rapid increase of greenhouse gas forcing

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 39-45页

作者： Haolan Ren Fei Zheng Tingwei cao Qiang Wang International Center for Climate and Environment Science(ICCES) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina University of Chinese Academy of Sciences BeijingChina College of Oceanography Hohai UniversityNanjingChina CAS Key Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of Sciences and Pilot National Laboratory for Marine Science and Technology(Qingdao)QingdaoChina

Atlantic Meridional Overturning Circulation(AMOC)plays a central role in long-term climate variations through its heat and freshwater transports,which can collapse under a rapid increase of greenhouse gas forcing in climate *** studies have suggested that the deviation of model parameters is one of the major factors in inducing inaccurate AMOC *** this work,with a low-resolution earth system model,the authors try to explore whether a reasonable adjustment of the key model parameter can help to re-establish the AMOC after its *** a new optimization strategy,the extra freshwater flux(FWF)parameter is determined to be the dominant one affecting the AMOC’s *** traditional ensemble optimal interpolation(EnOI)data assimilation and new machine learning methods are adopted to optimize the FWF parameter in an abrupt 4×CO_(2) forcing experiment to improve the adaptability of model parameters and accelerate the recovery of *** results show that,under an abrupt 4×CO_(2) forcing in millennial simulations,the AMOC will first collapse and then re-establish by the default FWF parameter ***,during the parameter adjustment process,the saltier and colder sea water over the North Atlantic region are the dominant factors in usefully improving the adaptability of the FWF parameter and accelerating the recovery of AMOC,according to their physical relationship with FWF on the interdecadal timescale.

关键词： Recovery of AMOC 4×CO_(2)forcing Key parameter Parameter estimation Data assimilation Machine learning

Unraveling post-growth mechanisms of monolayer CsPbBr3 nanocubes:Laser-enhanced transformations and cathodoluminescence-electron microscopy correlations

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Journal of Energy Chemistry 2025年第1期100卷 146-156页

作者： Mingxing Li Xiaoge Wang Xiaofan cao Zhiqun He Chunjun Liang Mingxing Chen Jing Ju Fangtian You Key Laboratory of Luminescence and Optical Information Ministry of Education Institute of Optoelectronic Technology Beijing Jiaotong University Beijing National Laboratory for Molecular Sciences (BNLMS) College of Chemistry and Molecular Engineering Peking University

Lead-halide perovskite nanoparticles（LHP NPs） are highly promising materials for next-generation displays and solid-state lighting due to their exceptional optical properties. However, their inherent instability presents a significant challenge. Recent advances have demonstrated that optoelectronic devices based on monolayer nanoparticle films exhibit both high luminescence efficiency and long-term *** research demonstrates that mobility limitations and anisotropic alignments in CsPbBr3nanocube monolayer films are key to their stabilization, hindering spontaneous growth through face-to-face fusion and resulting in the formation of connecting necks in a diagonal direction. Introducing laser irradiation confirmed this by significantly accelerating nanocubes growth, increasing mobility, and enhancing local structural ordering, leading to larger and more regularly shaped nanosheets. Fourier transform infrared spectroscopy and energy dispersive spectroscopy line-scan analyses indicated that laser irradiation did not disrupt the ligand structure. Transmission electron microscopy and correlative cathodoluminescence electron microscopy revealed the effects of post-growth and heterogeneous structures, including enhanced luminescence and inhomogeneous intensity in the nanosheets. These findings deepen the understanding of the post-growth mechanism of monolayer nanoparticles and the structure-emission correlation and highlight the unique role of laser irradiation in directing the formation of well-defined and regular nanostructures.

关键词： Post-growth mechanism Heterogeneous structure Single-particle spectroscopy Laser irradiation

Mitophagy in acute central nervous system injuries:regulatory mechanisms and therapeutic potentials

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Neural Regeneration Research 2025年第9期20卷 2437-2453页

作者： Siyi Xu Junqiu Jia Rui Mao Xiang cao Yun Xu Department of Neurology Nanjing Drum Tower HospitalClinical College of Jiangsu UniversityNanjingJiangsu ProvinceChina Department of Neurology Nanjing Drum Tower HospitalChinese Academy of Medical Science&Peking Union Medical CollegeNanjingJiangsu ProvinceChina Department of Neurology Nanjing Drum Tower HospitalAffiliated Hospital of Medical SchoolNanjing UniversityNanjingJiangsu ProvinceChina State Key Laboratory of Pharmaceutical Biotechnology and Institute of Translational Medicine for Brain Critical Diseases Nanjing UniversityNanjingJiangsu ProvinceChina Jiangsu Key Laboratory for Molecular Medicine Medical School of Nanjing UniversityNanjingJiangsu ProvinceChina Nanjing Neurology Medical Center NanjingJiangsu ProvinceChina

Acute central nervous system injuries,including ischemic stro ke,intracerebral hemorrhage,subarachnoid hemorrhage,traumatic brain injury,and spinal co rd injury,are a major global health *** optimal therapies and improving the long-term neurological functions of patients with acute central nervous system injuries are urgent *** are susceptible to damage after acute central nervous system injury,and this leads to the release of toxic levels of reactive oxygen species,which induce cell ***,a selective form of autophagy,is crucial in eliminating redundant or damaged mitochondria during these *** evidence has highlighted the significant role of mitophagy in acute central nervous system *** this review,we provide a comprehensive overview of the process,classification,and related mechanisms of *** also highlight the recent developments in research into the role of mitophagy in various acute central nervous system injuries and drug therapies that regulate *** the final section of this review,we emphasize the potential for treating these disorders by focusing on mitophagy and suggest future research paths in this area.

关键词： autophagy intracerebral hemorrhage ischemic stroke mitochondria mitochondrial biogenesis mitochondrial quality control mitophagy spinal cord injury subarachnoid hemorrhage traumatic brain injury

现代体属性分析技术在风化壳气藏勘探中的应用——以苏里格气田桃7区块马五_1~3段为例

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物探与化探 2016年第3期40卷 445-451页

作者：韩翀陈明江赵辉曹博超李金玺尹晓贺中石油川庆钻探工程公司地质勘探开发研究院四川成都610051 成都理工大学能源学院四川成都610059 东方地球物理公司研究院地质研究中心河北涿州072751

鄂尔多斯盆地苏里格气田奥陶系马家沟组风化壳储层厚度薄,非均值性强,气水关系复杂,其储层发育受沉积、构造、成岩等多因素共同作用,勘探难度极大。以桃7区块马五_1~3段为例,结合风化壳储层发育特点及储层段地球物理响应特征,应用现代... 详细信息

鄂尔多斯盆地苏里格气田奥陶系马家沟组风化壳储层厚度薄,非均值性强,气水关系复杂,其储层发育受沉积、构造、成岩等多因素共同作用,勘探难度极大。以桃7区块马五_1~3段为例,结合风化壳储层发育特点及储层段地球物理响应特征,应用现代体属性分析技术对古岩溶风化壳储层进行了针对性研究,其中包括应用构造导向滤波技术提高原始地震资料信噪比,并在此基础上应用体曲率和蚂蚁追踪技术综合预测微断裂;应用地层切片及体融合技术精细刻画古岩溶沟槽。预测结果表明,现代体属性分析技术可以更充分地利用常规地震资料进行风化壳储层精细描述,减少预测多解性。多种技术方法通过实钻井验证,吻合度较高,为研究区下一步的油气勘探提供了良好的依据。

关键词：现代体属性岩溶风化壳构造导向滤波蚂蚁追踪体曲率体融合

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日本知识界认知中的五四运动

河北学刊 2025年第1期45卷 210-217页

作者：曹萌中国社会科学院

五四运动爆发后,日本主流舆论将其定性为“排日运动”,多指责中国青年学生排斥日本,认为英美势力与中国亲英美派政客煽动青年学生促成了“暴动”。部分日本在华媒体人和以吉野作造为代表的日本新知识分子以及大阪报刊《大正日日新闻》... 详细信息

五四运动爆发后,日本主流舆论将其定性为“排日运动”,多指责中国青年学生排斥日本,认为英美势力与中国亲英美派政客煽动青年学生促成了“暴动”。部分日本在华媒体人和以吉野作造为代表的日本新知识分子以及大阪报刊《大正日日新闻》却肯定了五四运动体现出的进步思想,呼吁日本民众理性看待中国的民众运动。其中,《大正日日新闻》1920年新年号连载“中国名士之对日意见”,这些意见集中介绍了五四运动、新思想运动的真义,体现了五四运动后日本知识界对中国新思想的关注,同时也呈现出日本对华观的多面性与复杂性。

关键词：五四运动中日关系吉野作造《大正日日新闻》

Gut microbiota-astrocyte axis: new insights into age-related cognitive decline

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Neural Regeneration Research 2025年第4期20卷 990-1008页

作者： Lan Zhang Jingge Wei Xilei Liu Dai Li Xiaoqi Pang Fanglian Chen Hailong cao Ping Lei Haihe Laboratory of Cell Ecosystem Department of GeriatricsTianjin Medical University General HospitalTianjinChina Tianjin Geriatrics Institute Tianjin Medical University General HospitalTianjinChina Department of Gastroenterology and Hepatology Tianjin Medical University General HospitalNational Key Clinical SpecialtyTianjin Institute of Digestive DiseasesTianjin Key Laboratory of Digestive DiseasesTianjinChina Department of Urology Tianjin Medical University General HospitalTianjinChina Tianjin Neurological Institution Tianjin Medical University General HospitalTianjinChina

With the rapidly aging human population,age-related cognitive decline and dementia are becoming increasingly prevalent *** is considered the main risk factor for cognitive decline and acts through alterations in the composition of the gut microbiota,microbial metabolites,and the functions of *** microbiota–gut–brain axis has been the focus of multiple studies and is closely associated with cognitive *** article provides a comprehensive review of the specific changes that occur in the composition of the gut microbiota and microbial metabolites in older individuals and discusses how the aging of astrocytes and reactive astrocytosis are closely related to age-related cognitive decline and neurodegenerative *** article also summarizes the gut microbiota components that affect astrocyte function,mainly through the vagus nerve,immune responses,circadian rhythms,and microbial ***,this article summarizes the mechanism by which the gut microbiota–astrocyte axis plays a role in Alzheimer’s and Parkinson’s *** findings have revealed the critical role of the microbiota–astrocyte axis in age-related cognitive decline,aiding in a deeper understanding of potential gut microbiome-based adjuvant therapy strategies for this condition.

关键词： age aging Alzheimer’s disease astrocytes cognitive decline dementia gut microbiota gut–brain axis microbial metabolites neuroinflammation Parkinson’s disease