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Sparse Modal Decomposition Method Addressing Underdetermined Vortex-Induced Vibration Reconstruction Problem for Marine Risers

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China Ocean Engineering 2024年第2期38卷 285-296页

作者： du Zun-feng ZHU hai-ming YU Jian-xing State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation School of Civil EngineeringTianjin UniversityTianjin 300350China

When investigating the vortex-induced vibration(VIV)of marine risers,extrapolating the dynamic response on the entire length based on limited sensor measurements is a crucial step in both laboratory experiments and fatigue monitoring of real *** problem is conventionally solved using the modal decomposition method,based on the principle that the response can be approximated by a weighted sum of limited vibration ***,the method is not valid when the problem is underdetermined,i.e.,the number of unknown mode weights is more than the number of known *** study proposed a sparse modal decomposition method based on the compressed sensing theory and the Compressive Sampling Matching Pursuit(Co Sa MP)algorithm,exploiting the sparsity of VIV in the modal *** the validation study based on high-order VIV experiment data,the proposed method successfully reconstructed the response using only seven acceleration measurements when the conventional methods failed.A primary advantage of the proposed method is that it offers a completely data-driven approach for the underdetermined VIV reconstruction problem,which is more favorable than existing model-dependent solutions for many practical applications such as riser structural health monitoring.

关键词： motion reconstruction vortex-induced vibration(VIV) marine riser modal decomposition method compressed sensing

Phase order in one-dimensional piecewise linear discontinuous map

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Chinese Physics B 2018年第10期27卷 240-244页

作者： Ru-hai du Sheng-Jun Wang Tao Jin Shi-Xian Qu Institute of Theoretical ＆ Computational Physics Shaanxi Normal UniversityXi＇an 710119China School of Physics and Information Technology Shaanxi Normal UniversityXi＇an 710119China

The phase order in a one-dimensional（1 D） piecewise linear discontinuous map is investigated. The striking feature is that the phase order may be ordered or disordered in multi-band chaotic regimes, in contrast to the ordered phase in continuous systems. We carried out an analysis to illuminate the underlying mechanism for the emergence of the disordered phase in multi-band chaotic regimes, and proved that the phase order is sensitive to the density distribution of the trajectories of the attractors. The scaling behavior of the net direction phase at a transition point is observed. The analytical proof of this scaling relation is obtained. Both the numerical and analytical results show that the exponent is 1, which is controlled by the feature of the map independent on whether the system is continuous or discontinuous. It extends the universality of the scaling behavior to systems with discontinuity. The result in this work is important to understanding the property of chaotic motion in discontinuous systems.

关键词： chaos piecewise discontinuous map direction phase

Effect of purine-rich box1 on proliferation of fibroblasts

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International Journal of Ophthalmology(English edition) 2020年第11期13卷 1827-1832页

作者： Ke Lu hai-Tao du Ai-Ling Lian Ying Su Feng Wang Department of Ophthalmology the First Affiliated Hospital of Harbin Medical UniversityHarbin 150001Heilongjiang ProvinceChina Department of Centric Operating Room the First Affiliated Hospital of Harbin Medical UniversityHarbin 150001Heilongjiang ProvinceChina

Fibroblasts are pleomorphic cells that have a multidirectional effect on organ morphogenesis,tissue homeostasis,and immune *** fibrotic diseases,fibroblasts synthesize large amounts of extracellular matrix(ECM),leading to scarring and organ ***-rich boxl(PU.I)is a specific transcription factor of hematopoietic cell and belongs to the E26 transformation specificity(ETS)***,it was found that the transcription factor PU.I is an important regulatory factor of the profibrotic gene expression ***-J3 had been proved to play an important role in many ocular tissue fibrosis diseases,and up-regulated the expression of PU.I in fibroblasts producing ECM in a Smad-3 dependent *** explore the effect of PU.I on fibrosis of different ocular tissues from this *** article reviews the role of PU.l and its effects on fibrosis of ocular tissue and other tissues.

关键词： purine-rich boxl TGF-P extracellular matrix fibroblasts fibrosis ocular tissue

Analysis of flow separation control using nanosecond-pulse discharge plasma actuators on a flying wing

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Plasma Science and Technology 2018年第11期20卷 116-125页

作者： Zheng LI Zhiwei SHI hai du Qijie SUN Chenyao WEI Xi GENG College of Aerospace Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016 People＇s Republic of China The Key Laboratory of Fluid and Power Machinery Xihua UniversityChengdu 610039People＇s Republic of China

Dielectric barrier discharge （DBD） plasma is one of most promising flow control method for its several advantages. The present work investigates the control authority of nanosecond pulse DBD plasma actuators on a flying wing model＇s aerodynamic characteristics. The aerodynamic forces and moments are studied by means of experiment and numerical simulation. The numerical simulation results are in good agreement with experiment results. Both results indicate that the NS-DBD plasma actuators have negligible effect on aerodynamic forces and moment at the angles of attack smaller than 16-. However, significant changes can be achieved with actuation when the model＇s angle of attack is larger than 16° where the flow separation occurs. The spatial flow field structure results from numerical simulation suggest that the volumetric heat produced by NS-DBD plasma actuator changes the local temperature and density and induces several vortex structures, which strengthen the mixing of the shear layer with the main flow and delay separation or even reattach the separated flow.

关键词： nanosecond dielectric barrier discharge flying wing aircraft flow separation control

High Performance Humidity Sensor Based on Electrospun Zr_(0.9)Mg_(0.1)O_(2−δ) Nanofibers

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Chinese Physics Letters 2012年第11期29卷 27-30页

作者： SU Mei-Ying WANG Jing YAO Peng-Jun du hai-Ying School of Electronic Science and Technology Dalian University of TechnologyDalian 116023 Institute of Microelectronics of Chinese Academy SciencesBeijing 100029 School of Educational Technology Shenyang Normal UniversityShenyang 110034 Department of Electromechanical Engineering&Information Dalian Nationalities UniversityDalian 116600

Zr_(0.9)Mg_(0.1)O_(2−δ) nanofibers and ZrO_(2) nanofibers are synthesized using electrospinning and the calcination *** nanofibers are characterized using x-ray diffraction(XRD),a field emission scanning electron microscope(FE-SEM),and a Brunauer–Emmett–Teller(BET)surface *** humidity sensing properties of Zr_(0.9)Mg_(0.1)O_(2−δ) nanofiber sensors are analyzed and compared with those of ZrO_(2) nanofiber *** Zr_(0.9)Mg_(0.1)O_(2−δ) nanofiber humidity sensors exhibit a broader humidity range of 11–97%relative humidity(RH),good linearity,small humidity hysteresis,and rapid response and recovery *** complex impedance plots of the Zr_(0.9)Mg_(0.1)O_(2−δ) sensor at different RHs are drawn,and the humidity sensing mechanism is discussed via an equivalent circuit.

关键词： fibers humidity fiber

Clinical Observation on Aligned Needling in Treating Idiopathic Blepharospasm

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Journal of Acupuncture and Tuina Science 2013年第2期11卷 101-103页

作者： du hai-ying Yu Xing-yuan Hong Jue Ophthalmology Department Hangzhou Hospital of Traditional Chinese Medicine Ophthalmology Department Dongfang Hospital Affiliated to Beijing University of Traditional Chinese Medicine

Objective:To observe the clinical effect of aligned needling method in treating idiopathic ***:Seventy-eight patients with idiopathic blepharospasm were randomized into two ***-six cases in the treatment group were treated with aligned needling method applied to orbicularis oculi muscles;32 cases in the control group were treated with *** effects were compared after 3 treatment ***:The total effective rate was 93.5%in the treatment group versus75.0%in the control group,and the difference was statistically significant(P<0.05).Conclusion:Aligned needling method applied to orbicularis oculi muscle has better therapeutic effect than anticonvulsants in treating blepharospasm.

关键词： Acupuncture Therapy Needling Methods Blepharospasm

Screener3D:a gaseous time projection chamber for ultra-low radioactive material screening

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Nuclear Science and Techniques 2021年第12期32卷 103-115页

作者： hai-Yan du Cheng-Bo du Karl Giboni Ke Han Sheng-Ming He Li-Qiang Liu Yue Meng Shao-Bo Wang Tao Zhang Li Zhao Ji-Fang Zhou INPAC Shanghai Laboratory for Particle Physics and CosmologyKey Laboratory for Particle Astrophysics and Cosmology(MOE)School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Yalong River Hydropower Development Company Ltd.288 Shuanglin RoadChengdu 610051China SJTU-ParisTech Elite Institute of Technology(SPEIT) Shanghai Jiao Tong UniversityShanghai 200240China

In experiments searching for rare signals,background events from the detector itself are some of the major factors limiting search *** for ultra-low radioactive detector materials is becoming ever more *** propose to develop a gaseous time projection chamber(TPC)with a Micromegas readout for radio *** TPC records three-dimensional trajectories of charged particles emitted from a flat sample placed in the active volume of the *** detector can distinguish the origin of an event and identify the particle types with information from trajectories,which significantly increases the screening *** a particles from the sample surface,we observe that our proposed detector can reach a sensitivity higher than 100 l Bq m-2 within two days.

关键词： Charged-particle detector Surface a measurement Ultra-low radioactivity Material screening

Application of Geometric Midline Yield Criterion for Strip Drawing

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Journal of Iron and Steel Research International 2009年第6期16卷 13-16页

作者： WANG Gen-ji du hai-jun ZHAO De-wen LIU Xiang-hua WANG Guo-dong State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 Liaoning China

A new linear yield criterion expressed by the geometric midline of error triangle between Tresca and Twin shear stress yield loci on the π-plane in haigh-Westergaard space was introduced. The criterion was written in terms of the values of principal stress deviator and called GM yield criterion for short. Together with a Cartesian coordinate velocity field instead of the Avitzur＇s, the GM criterion was used to obtain an analytical solution for strip drawing. With a working example of the strip drawing through wedge-shaped die, the results of relative drawing stress calculated by the GM criterion were compared with those calculated by Mises＇ criterion from Avitzur formula. It indicated that the calculated results according to analytical solution were in good agreement with the numerical solution obtained from Avitzur formula.

关键词： GM yield criterion strip drawing analytical solution

黄土丘陵沟壑区混交林林下植被与土壤养分特征

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绿色科技 2024年第8期26卷 25-32页

作者：逯欣悦杨光吴际陆乃静麻云霞杜海内蒙古农业大学内蒙古呼和浩特010019 内蒙古杭锦荒漠生态系统国家定位观测研究站内蒙古鄂尔多斯017400 中央与地方共建风沙物理重点实验室内蒙古呼和浩特010018 准格尔旗水利事业发展中心内蒙古鄂尔多斯010321

为研究黄土丘陵沟壑区坡面不同类型混交林林下植被多样性与土壤养分特征及两者间的互馈关系,进而筛选植被恢复的适宜配置方案,以期为黄土丘陵沟壑区土壤侵蚀防控措施中植被类型、配置的选择提供科学依据。以油松×杏树(Ⅰ)、油松×柠条(... 详细信息

为研究黄土丘陵沟壑区坡面不同类型混交林林下植被多样性与土壤养分特征及两者间的互馈关系,进而筛选植被恢复的适宜配置方案,以期为黄土丘陵沟壑区土壤侵蚀防控措施中植被类型、配置的选择提供科学依据。以油松×杏树(Ⅰ)、油松×柠条(Ⅱ)、杏树×柠条(Ⅲ)3种混交林为研究对象,以立地条件类似的传统水土保持植被油松纯林(CK)为对照,通过调查林下植被多样性及0~60 cm深土层的土壤性质,分析了不同植被类型下两者间的差异与相互关系。结果表明:各样地均以禾本科植物为主,植物种数比较为:混交林Ⅱ=混交林Ⅲ>混交林Ⅰ>纯林CK,各多样性指数均比较为:混交林Ⅱ>混交林Ⅲ>混交林Ⅰ>纯林CK。各样地有机质含量和全效氮、全磷、全钾含量均比较为:混交林Ⅱ>混交林Ⅲ>混交林Ⅰ>纯林CK。通过相关分析发现,Simpson优势度指数与土壤有机质、全氮含量呈显著正相关(P<0.05),与全钾含量呈极显著正相关(P<0.05);Margalef丰富度指数与土壤有机质、全氮、全钾含量呈极显著正相关(P<0.05);各样地土壤养分与植被多样性间联系密切,相互影响。3种混交林的林下植被多样性和土壤养分含量均显著高于油松纯林,油松×杏树混交林(Ⅱ)综合表现最优。

关键词：黄土丘陵沟壑区混交林植物多样性土壤养分