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A Review on Vibration Control of Multiple Cylinders Subjected to FlowInduced Vibrations

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China Ocean Engineering 2024年第2期38卷 183-197页

作者： XU wan-hai MA Ye-xuan State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation Tianjin UniversityTianjin 300350China Institute of Mechanics Chinese Academy of SciencesBeijing 100190China

The fatigue damage caused by flow-induced vibration(FIV)is one of the major concerns for multiple cylindrical structures in many engineering *** FIV suppression is of great importance for the security of many cylindrical *** active and passive control methods have been employed for the vibration suppression of an isolated cylinder undergoing vortex-induced vibrations(VIV).The FIV suppression methods are mainly extended to the multiple cylinders from the vibration control of the isolated *** to the mutual interference between the multiple cylinders,the FIV mechanism is more complex than the VIV mechanism,which makes a great challenge for the FIV *** efforts have been devoted to vibration suppression of multiple cylinder systems undergoing FIV over the past two *** control methods,such as helical strakes,splitter plates,control rods and flexible sheets,are not always effective,depending on many influence factors,such as the spacing ratio,the arrangement geometrical shape,the flow velocity and the parameters of the vibration control *** FIV response,hydrodynamic features and wake patterns of the multiple cylinders equipped with vibration control devices are reviewed and *** FIV suppression efficiency of the vibration control methods are analyzed and compared considering different influence *** research on the FIV suppression of multiple cylinders is suggested to provide insight for the development of FIV control methods and promote engineering applications of FIV control methods.

关键词： flow-induced vibration vibration control multiple cylinders tandem side-by-side staggered

Hollow Multi-shelled Structure Photoelectric Materials: Multiple Shells Bring Novel Properties

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Chemical Research in chinese Universities 2024年第3期40卷 413-427页

作者： SU Fengmei wan Jiawei wanG Dan State Key Laboratory of Biochemical Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190P.R.China University of chinese academy of sciences Beijing 100049P.R.China Key Laboratory of Biopharmaceutical Preparation and Delivery Chinese AcademyofSciencesBeijing 100049P.R.China

Hollow multi-shelled structures(HoMSs)have made significant strides across a wide spectrum of scientific investigations since the inception of the sequential templating approach(STA)in 2009,revealing distinctive temporal-spatial ordering *** recent establishment of a mathematical model for STA has not only demystified the formation of concentration waves within the STA process but also extended its relevance to gentler solutionbased systems,thereby broadening the HoMs ***,focusing on photoelectric applications,this review first summarizes the unique temporal-spatial ordering features of ***,the greatly enhanced properties of light capture and absorption,exciton separation,and transfer are deeply ***,we conclude with a perspective on the potential challenges and burgeoning opportunities that lie ahead in the advancement of HoMs development.

关键词： Hollow multi-shelled structure Photoelectric conversion Sequential templating approach Light absorption Chargetransfer

Ages and Compositions of the Precambrian High-grade Basement of the Qilian Terrane and Its Adjacent Areas

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Acta Geologica Sinica(English Edition) 2001年第4期75卷 375-384页

作者： wan Yusheng, XU Zhiqin, YANG Jingsui and ZHANG Jianxin Institute of Geology, chinese academy of Geological {3., {3. 10003. Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 [?]2wan Yusheng Born in 1958 graduated from China University of Geosciences in 1981 received the Ph.D. degree in 1993 now senior geologist at the Institute of Geology Chinese Academy of Geological Sciences engaged in the study of geochemistry. Tel: 010–683.8411 e-mail: wanysh@***

Based on geological, chronological, geochemical and Nd isotopic studies of the high-grade basement of the Qilian terrane, the authors have drawn the following main conclusions: (1) the high-grade basement of the Qilian terrane consists mainly of meta-argillo-arenaceous rocks and granites and its bulk part was formed in the period of 0.8–1.0 Ga (the Jinningian period); (2) most of the meta-argillo-arenaceous rocks and granitic rocks have strong negative Eu and Ba anomalies (Eu/Eu*= 0.47–0.71 and Ba/Ba*=0.16–0.64), with fDM and ENd (1.0 Ga) ranging from 1.87 to 2.26 Ga and from ?8.54 to ?4.06 respectively, showing relatively high maturity; and (3. the Jinningian granitic rocks are a typical product of continent-continent collision, being probably related to the formation of the supercontinent Rodinia. These studies, combined with the study of high-grade basement rocks near the Qilian terrane, suggest that before the Jinningian period, the Qilian-Qaidam northern-margin terrane and Dunhuang-Alxa terrane were separated from each other, belonging to different plate systems of the North China craton and Yangtze platform respectively. The Qilian orogenic belt was the same as or similar to the Qiling orogenic belt in terms of the geological evolution history at least before the Jinningian period.

关键词： Qilian terrane chronology Nd isotope geochemistry Precambrian basement

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带交易费用的泛证券组合投资策略

系统工程理论与实践 2003年第1期23卷 22-25,87页

作者：刘善存邱菀华汪寿阳北京航空航天大学经济管理学院北京100083 中国科学院数学与系统科学研究院系统科学研究所北京100080

研究带交易费用的泛证券组合投资策略 ,得到一些有趣的结论。

关键词：交易费用泛证券组合投资策略证券市场投资组合定常再调整策略现代投资理论

Analysis and Design for Third Order Nonlinear Continuous Extended States Observer

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Analysis and Design for Third Order Nonlinear Continuous Ext...

How mutual funds respond to asymmetric feedback tradingin China’s stock market

第十九届中国控制会议

作者： Yi Huang Hui wan Jinlai Song Institute of systems science, {3. of Mathematics and systems science, chinese academy of sciences, beijing 100080, P. R. China,

＜正＞The Extended State Observer （ESO） is a novel observer for a class of uncertain systems. Since ESO adopts the continuous non-smooth structure, the classical observer design theory is hard to be use for ESO analysis, especially for third order ESO. Till now, there axe few results about theoretical analysis for third order ESO. In this paper, the Self-Stable Region （SSR） approach, which is a nonlinear synthesis method for nonlinear uncertain systems, will be used for analysis and design for third order ESO.

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Journal of Management science and Engineering 2024年第2期9卷 143-160页

作者： Die wan Li Yang Xiaoguang Yang School of Finance Zhejiang Gongshang UniversityHangzhou310018China Business School University of New South WalesSydneyAustralia academy of Mathematics and systems science Chinese Academy of SciencesBeijingChina

Previous studies show that individual investors play a dominant role in China's stock *** behavior of chasing-rise being stronger than killing-fall leads to asymmetry of feedback *** article investigates how mutual funds react to this market *** China's stock and fund data from 2003.to 2019,we find that mutual funds tend to hold fewer shares when asymmetric feedback trading of the relevant stock gets more *** negative relationship is robust after controlling past returns,turnover rates,and firm risk factors,moreover,it attenuates when the market sentiment is bullish or when stocks are allowed *** results show that mutual funds'selling towards asymmetric feedback trading does not make excess return but leads to significant risk *** findings may be related to uncertainty associated with asymmetric feedback trading,and thus support the limit market participation theory from the second largest stock market.

关键词： Asymmetric feedback trading Mutual fund shareholdings Uncertainty Market sentiment Short selling

An empirical method for joint inversion of wave and wind parameters based on SAR and wave spectrometer data

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Acta Oceanologica Sinica 2024年第5期43卷 133-144页

作者： Yong wan Xiaona Zhang Shuyan Lang Ennan Ma Yongshou Dai College of Oceanography and Space Informatics China University of PetroleumQingdao 266580China National Satellite Marine Application Center Beijing 100081China Key Laboratory of Space Ocean Remote Sensing and Application Ministry of Natural ResourcesBeijing 100081China College of Control science and Engineering China University of PetroleumQingdao 266580China

Synthetic aperture radar(SAR)and wave spectrometers,crucial in microwave remote sensing,play an essential role in monitoring sea surface wind and wave ***,they face inherent limitations in observing sea surface *** systems,for instance,are hindered by an azimuth cut-off phenomenon in sea surface wind field *** spectrometers,while unaffected by the azimuth cutoff phenomenon,struggle with low azimuth resolution,impacting the capture of detailed wave and wind field *** study utilizes SAR and surface wave investigation and monitoring(SWIM)data to initially extract key feature parameters,which are then prioritized using the extreme gradient boosting(XGBoost)*** research further addresses feature collinearity through a combined analysis of feature importance and correlation,leading to the development of an inversion model for wave and wind parameters based on XGBoost.A comparative analysis of this model with ERA5 reanalysis and buoy data for of significant wave height,mean wave period,wind direction,and wind speed reveals root mean square errors of 0.212 m,0.525 s,27.446°,and 1.092 m/s,compared to 0.3.4 m,0.888 s,27.698°,and 1.3.5 m/s from buoy data,*** results demonstrate the model’s effective retrieval of wave and wind ***,the model,incorporating altimeter and scatterometer data,is evaluated against SAR/SWIM single and dual payload inversion methods across different wind *** comparison highlights the model’s superior inversion accuracy over other methods.

关键词： synthetic aperture radar(SAR) wave spectrometer extreme gradient boosting(XGBoost) joint inversion method wave and wind parameters

A columnar multi-layer sliding triboelectric nanogenerator for water wave energy harvesting independent of wave height and direction

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Nano Research 2024年第4期17卷 3029-3034页

作者： Xue Miao Hanxiao Yang Zekun Li Meifei Cheng Yilin Zhao Lingyu wan Aifang Yu Junyi Zhai Center on NanoEnergy Research School of Physical Science and TechnologyGuangxi UniversityNanning 530004China beijing Institute of Nano Energy and Nano systems Chinese Academy of SciencesBeijing 101400China School of Nanoscience and Engineering University of Chinese Academy of ScienceBeijing 101408China

The ocean,with its highly variable and complex meteorological conditions,harbors enormous renewable *** nanogenerators(TENGs),which possess unique advantages,show exciting prospects in water wave energy *** to design and optimize TENGs to cover all characteristic water wave energies and achieve efficient energy utilization is *** this paper,we carefully designed and fabricated a columnar multi-layer sliding TENG(CMLS-TENG)that can harvest water wave energy independent of wave height and *** rods with a hollow acrylic spherical shell were introduced to deliver wave energy,ensuring that the CMLS-TENG can work in all directions from 0°to 3.0°.Based on the sliding structure,switching the optimized CMLS-TENG is independent of wave *** optimized CMLS-TENG can achieve a total power density of 73. mW/m^(3. at a wave height of only 4.8 cm regardless of wave direction,which can illuminate multiple light-emitting diodes(LEDs)to provide lighting and provide power to a watch and a hygrometer for temperature and humidity *** work provides new choices and hopes for the effective collection of full-range water wave energy.

关键词： triboelectric nanogenerator wave energy multi-direction columnar slide

NONLINEAR FEEDFORWARD SEQUENCES OF m-SEQUENCES (Ⅲ)

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systems science and Mathematical sciences 1994年第4期7卷 367-370页

作者： DAI Zongduo(Graduate School,Academia Sinica, beijing 10003., China)FENG Xuuing(Institute of Mathematics,Academia Sinica, beijing 100080, China)LIU Mulan wan Zhexian(Institute of {3. {3., Academia Sinica, beijing 100080, China)

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关键词： Non-degenerate monomial function congruent monomial function