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Nonlinear Flap-Wise Vibration Characteristics ofWind Turbine Blades Based onMulti-Scale AnalysisMethod

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Energy Engineering 2024年第2期121卷 483-498页

作者： qifa Lang Yuqiao Zheng Tiancai Cui Chenglong Shi Heyu Zhang School of Mechanical and Electrical Engineering Lanzhou University of TechnologyLanzhou730050China

This work presents a novel approach to achieve nonlinear vibration response based on the Hamilton principle.We chose the 5-MW reference wind turbine which was established by the National Renewable Energy Laboratory(NREL),to research the effects of the nonlinear flap-wise vibration characteristics.The turbine wheel is simplified by treating the blade of a wind turbine as an Euler-Bernoulli beam,and the nonlinear flap-wise vibration characteristics of the wind turbine blades are discussed based on the simplification first.Then,the blade’s large-deflection flap-wise vibration governing equation is established by considering the nonlinear term involving the centrifugal force.Lastly,it is truncated by the Galerkin method and analyzed semi-analytically using the multi-scale analysis method,and numerical simulations are carried out to compare the simulation results of finite elements with the numerical simulation results using Campbell diagram analysis of blade vibration.The results indicated that the rotational speed of the impeller has a significant impact on blade vibration.When the wheel speed of 12.1 rpm and excitation amplitude of 1.23 the maximum displacement amplitude of the blade has increased from 0.72 to 3.16.From the amplitude-frequency curve,it can be seen that the multi-peak characteristic of blade amplitude frequency is under centrifugal nonlinearity.Closed phase trajectories in blade nonlinear vibration,exhibiting periodic motion characteristics,are found through phase diagrams and Poincare section diagrams.

关键词： Wind turbine blades nonlinear vibration Galerkin method multi-scales method

Investigation on photonic crystal nanobeam cavity based on mixed diamond–circular holes

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Nanotechnology and Precision Engineering 2024年第1期7卷 63-70页

作者： Jingtong Bin Kerui Feng Shang Ma Ke Liu Yong Cheng Jing Chen qifa Liu College of Telecommunication and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China College of Electronic and Optical Engineering and College of Flexible Electronics(Future Technology) Nanjing University of Posts and TelecommunicationsNanjing 210003China State Key Laboratory of Advanced Optical Communication Systems and Networks Shanghai Jiao Tong UniversityShanghai 200240China

A photonic crystal nanobeam cavity(M-PCNC)with a structure incorporating a mixture of diamond-shaped and circular air holes is pro-posed.The performance of the cavity is simulated and studied theoretically.Using theﬁnite-difference time-domain method,the parameters of the M-PCNC,including cavity thickness and width,lattice constant,and radii and numbers of holes,are optimized,with the quality factor Q and mode volume Vm as performance indicators.Mutual modulation of the lattice constant and hole radius enable the proposed M-PCNC to realize outstanding performance.The optimized cavity possesses a high quality factor Q 1.45105 and an ultra-small mode=×volume Vm 0.01(λ/n)[Zeng et al.,Opt Lett 2023:48;3981–3984]in the telecommunications wavelength range.Light can be progres-=sively squeezed in both the propagation direction and the perpendicular in-plane direction by a series of interlocked anti-slots and slots in the diamond-shaped hole structure.Thereby,the energy can be conﬁned within a small mode volume to achieve an ultra-high Q/Vm ratio.

关键词： Photonic crystal nanobeam cavity Mixed diamond–circular holes Slots and anti-slots FDTD simulation Quality factor Mode volume

The genetic basis and process of inbreeding depression in an elite hybrid rice

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Science China Life Sciences 2024年第8期 1727-1738页

作者： Xiaodong Xu Yawen Xu Jian Che Xu Han Zhengji wang Xianmeng wang Qinghua Zhang Xu Li Qinglu Zhang Jinghua Xiao Xianghua Li qifa Zhang Yidan Ouyang National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research (Wuhan) Hubei Hongshan LaboratoryHuazhong Agricultural University

Inbreeding depression refers to the reduced performance arising from increased homozygosity,a phenomenon that is the reverse of heterosis and exists among plants and animals.As a natural self-pollinated crop with strong heterosis,the mechanism of inbreeding depression in rice is largely unknown.To understand the genetic basis of inbreeding depression,we constructed a successive inbreeding population from the F2to F4generation and observed inbreeding depression of all heterotic traits in the progeny along with the decay of heterozygosity in each generation.The expected depression effect was largely explained by 13 QTLs showing dominant effects for spikelets per panicle,11 for primary branches,and 12 for secondary branches,and these loci constitute the main correlation between heterosis and inbreeding depression.However,the genetic basis of inbreeding depression is also distinct from that of heterosis,such that a biased transmission ratio of alleles for QTLs with either dominant or additive effects in four segregation distortion regions would result in minor effects in expected depression.Noticeably,two-locus interactions may change the extent and direction of the depression effects of the target loci,and overall interactions would promote inbreeding depression among generations.Using an F2:3variation population,the actual performance of the loci showing expected depression was evaluated considering the heterozygosity decay in the background after inbreeding.We found inconsistent or various degrees of background depression from the F2to F3generation assuming different genotypes of the target locus,which may affect the actual depression effect of the locus due to epistasis.The results suggest that the genetic architecture of inbreeding depression and heterosis is closely linked but also differs in their intrinsic mechanisms,which expand our understanding of the whole-genome architecture of inbreeding depression.

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人居环境治理中社会资本对村民参与行为的影响研究

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中国农业资源与区划 2024年第1期45卷 177-189页

作者：蒋其发郭淑华云南财经大学物流与管理工程学院昆明650221

[目的]探究个体因素和环境因素对提升村民参与农村人居环境治理行为的综合影响,明晰村民参与行为的激励机制,从而激发村民积极参与,可持续以相对较低成本改善农村人居环境质量。[方法]文章基于社会资本与政府规制整合视角,收集云南省27... 详细信息

[目的]探究个体因素和环境因素对提升村民参与农村人居环境治理行为的综合影响,明晰村民参与行为的激励机制,从而激发村民积极参与,可持续以相对较低成本改善农村人居环境质量。[方法]文章基于社会资本与政府规制整合视角,收集云南省278位村民的调研数据,构建结构方程模型(SEM)探讨村民参与行为的影响机理,并采用Process插件检验政府规制在社会资本影响村民参与行为中的调节作用。[结果](1)在农村人居环境治理中,社会资本显著正向影响村民参与行为;(2)道德责任感与群体认同感显著正向影响村民参与行为,并在社会资本与村民参与行为之间均起部分正向中介作用;(3)政府规制在村民社会资本与其参与行为之间部分起调节作用。其中,激励型规制起负向调节作用,存在对社会资本的挤占效应;而约束型规制调节作用不显著。[结论]农村人居环境治理过程中应坚持农民主体地位,以提升村民社会资本、提高村民的责任意识和群体认同感,减少激励型政策的挤占效应并慎用约束型政策,引导村民逐步实现自治,从而提升村民参与行为。

关键词：农村人居环境治理村民参与社会资本政府规制

Sentiment classification via user and product interactive modeling

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Science China(Information Sciences) 2021年第12期64卷 104-116页

作者： Xiabing ZHOU Zhongqing wang Min ZHOU qifa wang Shoushan LI Min ZHANG Guodong ZHOU School of Computer Science and Technology Soochow University

Sentiment classification aims to identify the polarity of a given review. Most existing methods consider each review as an individual while ignoring the importance of the user and product information of the given review. A direct way to integrate user and product information is to employ an attention mechanism to learn the local interaction between them. However, local interactions cannot capture the global optimization among user and product information. Therefore, we propose a novel interactive model to integrate both local and global interactions between users and products. In particular, we employ an attention mechanism to learn local interactions between users and products, and construct user and product interactive graphs to model the global interaction of users and products. Empirical evaluation shows that our model outperforms previous state-of-the-art methods significantly by learning the local and global interactions among users' preferences, product characteristics, and reviews.

关键词： product review analysis sentiment classification interactive graph graph convolutional network

出入高原全过程生活方式改良对高原脱适应症的影响

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陆军军医大学学报 2024年第11期46卷 1298-1305页

作者：王瑞赵佳罗其发罗勇军陆军军医大学(第三军医大学)陆军卫勤训练基地军事医学地理学教研室重庆400038 中国人民解放军31670部队宁夏吴忠751100

目的采用问卷调查出入高原全过程的生活方式对高原脱适应症(high-altitude de-adaptation,HADA)的影响,为防治HADA提供科学依据。方法采用病例-对照研究设计方案,以2021-2022年某单位集体从高原返回1~2周的1751人为调查对象,获得有效问... 详细信息

目的采用问卷调查出入高原全过程的生活方式对高原脱适应症(high-altitude de-adaptation,HADA)的影响,为防治HADA提供科学依据。方法采用病例-对照研究设计方案,以2021-2022年某单位集体从高原返回1~2周的1751人为调查对象,获得有效问卷1544份,根据高原脱适应症量表得分是否≥6分,将调查对象分为高原脱适应组(n=192)与对照组(n=1352)。对研究对象的生活习惯与一般情况进行问卷调查,通过秩和检验比较2组调查对象之间的生活方式是否存在差异,采用非条件Logistic回归分析明确HADA的独立危险因素。结果头发脱落(19.95%)、嗜睡(16.58%)和疲倦(12.31%)为最常见的高原脱适应症症状;且进入高原前高盐饮食,在高原时吸烟、出现高原反应(OR=1.893,95%CI:1.142~3.137,P=0.013)、乘飞机离开高原(OR=1.688,95%CI:1.082~2.634,P=0.021),离开高原后多饮茶、运动强度过高和睡眠不足均为HADA的独立危险因素。结论进入高原前清淡饮食、积极预防高原反应,在高原时戒烟、选择较慢的交通工具出入高原,离开高原后少饮茶、适量运动和保持睡眠充足可以有效降低HADA的发病风险。

关键词：高原脱适应症生活方式高海拔习服问卷调查

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国外捐献器官获取质量管理与控制进展

器官移植 2024年第2期15卷 191-199页

作者：金律范晓礼叶啟发武汉大学中南医院、武汉大学肝胆疾病研究院、武汉大学移植医学中心、国家人体捐献器官获取质量控制中心、移植医学技术湖北省重点实验室、湖北省天然高分子生物肝临床医学研究中心、湖北省天然高分子基医用材料构建工程技术研究中心武汉430071 中南大学湘雅三医院卫生部移植医学工程技术研究中心

器官移植是二十世纪以来有效挽救终末期器官衰竭患者生命的一项突破性技术,显著改善了患者生存质量。器官捐献作为器官移植的重要来源,提升捐献器官获取质量是促进捐献器官转化、改善器官移植预后的关键。美国、西班牙等国家在捐献器官... 详细信息

器官移植是二十世纪以来有效挽救终末期器官衰竭患者生命的一项突破性技术,显著改善了患者生存质量。器官捐献作为器官移植的重要来源,提升捐献器官获取质量是促进捐献器官转化、改善器官移植预后的关键。美国、西班牙等国家在捐献器官获取质量管理与控制方面提出了系列政策和标准,并取得了积极成果。本文通过探讨医疗质量管理与控制有关概念、国际捐献器官获取质量管理先进策略及模式,研究器官获取组织、捐献者、捐献器官质控举措,以期为形成具有“中国特色”的捐献器官获取质量管理与控制体系、推进捐献器官获取高速度高质量发展提供参考。

关键词：器官捐献器官获取器官获取组织(OPO) 质量管理管理模式质量控制器官移植

Augmenting photoluminescence of monolayer MoS_(2) using high order modes in a metal dimer-on-film nanocavity

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Photonics Research 2021年第4期9卷 501-506页

作者： Shiyin Cao Liping Hou qifa wang Chenyang Li Weixing Yu Xuetao Gan Kaihui Liu Malin Premaratne Fajun Xiao Jianlin Zhao MOE Key Laboratory of Material Physics and Chemistry under Extraordinary Conditions and Shaanxi Key Laboratory of Optical Information TechnologySchool of Physical Science and TechnologyNorthwestern Polytechnical UniversityXi’an 710129China Key Laboratory of Spectral Imaging Technology of Chinese Academy of Sciences Xi’an 710119China State Key Laboratory for Mesoscopic Physics Collaborative Innovation Centre of Quantum MatterSchool of PhysicsPeking UniversityBeijing 100871China Advanced Computing and Simulation Laboratory(AχL) Department of Electrical and Computer Systems EngineeringMonash UniversityClaytonVIC 3800Australia

Plasmonic particle-on-film nanocavities,supporting gap modes with ultra-small volume,provide a great solution to boost light–matter interactions at the nanoscale.In this work,we report on the photoluminescence(PL)enhancement of monolayer MoS_(2) using high order modes of an Au nanosphere dimer-on-film nanocavity(DoFN).The high order plasmon modes,consisting of two bonding quadrupoles in the dimer and their images in the Au film,are revealed by combining the polarization-resolved scattering spectra with the numerical simulations.Further integrating the monolayer MoS_(2) into the DoFN,these high order modes are used to enhance PL intensity through simultaneously boosting the absorption and emission processes,producing a 1350-fold enhancement factor.It opens an avenue to enhance the light–matter interaction with high order plasmon modes and may find applications in future optoelectronics and nanophotonics devices.

关键词： cavity high integrating

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涡激振动小圆柱对翼型气动力影响的数值研究

哈尔滨工程大学学报 2024年第4期45卷 739-747页

作者：陈东阳徐瑞张祥张启发芮筱亭西北工业大学海洋研究院江苏苏州215000 浙江金马逊智能制造股份有限公司浙江丽水321403 西北工业大学深圳研究院广东深圳518063 扬州大学电气与能源动力工程学院江苏扬州225100 海油发展珠海管道工程有限公司广东珠海519050 南京理工大学发射动力学研究所江苏南京210094

在大攻角来流时,翼型吸力面气流常产生流动分离现象,使翼型气动性能恶化。针对大攻角情况下的流动分离现象,本文在翼型前缘加入控制柱,通过数值仿真探究发生涡激振动的小圆柱对于翼型气动力的影响。基于计算流体力学、结构动力学和嵌套... 详细信息

在大攻角来流时,翼型吸力面气流常产生流动分离现象,使翼型气动性能恶化。针对大攻角情况下的流动分离现象,本文在翼型前缘加入控制柱,通过数值仿真探究发生涡激振动的小圆柱对于翼型气动力的影响。基于计算流体力学、结构动力学和嵌套网格技术,本文建立了二维流固耦合模型。以NACA0012翼型为例,对翼型前缘设置涡激振动圆柱的流场情况进行模拟,并且对比了静止圆柱与振动圆柱情况下的流场变化。通过流线图和涡量云图分析了小圆柱流动控制的机理。仿真结果表明:设置静止小圆柱可以提高大攻角下的翼型升阻比,使小圆柱产生涡激振动之后,能够进一步有效地提高大攻角下的翼型升阻比50%以上。涡激振动小圆柱的引入在大攻角条件下对提升翼型升阻比具有显著效果,为改善翼型气动性能提供了一种有效的流动控制手段。

关键词：数值模拟流动分离涡激振动计算流体力学翼型结构动力学柱体嵌套网格