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FVID: Fishing Vessel Type Identification Based on VMS Trajectories

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Journal of Ocean University of China 2019年第2期18卷 403-412页

作者： HUANG Haiguang HONG feng LIU Jing LIU Chao feng Yuan GUO Zhongwen College of Information Science and Engineering Ocean University of China Wenzhou Ocean and Fishery Vessel Safety Rescue Information Center

Vessel Monitoring System(VMS) provides a new opportunity for quantified fishing research. Many approaches have been proposed to recognize fishing activities with VMS trajectories based on the types of fishing vessels. However, one research problem is still calling for solutions, how to identify the fishing vessel type based on only VMS trajectories. This problem is important because it requires the fishing vessel type as a preliminary to recognize fishing activities from VMS trajectories. This paper proposes fishing vessel type identification scheme(FVID) based only on VMS trajectories. FVID exploits feature engineering and machine learning schemes of XGBoost as its two key blocks and classifies fishing vessels into nine types. The dataset contains all the fishing vessel trajectories in the East China Sea in March 2017, including 10031 pre-registered fishing vessels and 1350 unregistered vessels of unknown types. In order to verify type identification accuracy, we first conduct a 4-fold cross-validation on the trajectories of registered fishing vessels. The classification accuracy is 95.42%. We then apply FVID to the unregistered fishing vessels to identify their types. After classifying the unregistered fishing vessel types, their fishing activities are further recognized based upon their types. At last, we calculate and compare the fishing density distribution in the East China Sea before and after applying the unregistered fishing vessels, confirming the importance of type identification of unregistered fishing vessels.

关键词： VMS vessel type identification fishing density trajectory analysis classification

Vortex-induced vibration of pipes conveying fluid using the method of multiple scales

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Theoretical & Applied Mechanics Letters 2012年第2期2卷 64-67页

作者： Huliang dai Lin Wang Department of Mechanics Huazhong University of Science and TechnologyWuhan 430074China Hubei Key Laboratory for Engineering Structural Analysis and Safety Assessment Wuhan 430074China

The nonlinear dynamics of supported pipes conveying fluid subjected to vortex-induced vibration is evaluated using the method of multiple scales. Frequency response portraits for different internal fluid velocities under lock-in conditions are obtained and the stability of steady-state responses is discussed. Results show that the internal fluid velocity has a prominent effect on the oscillation amplitude and that the steady-state responses incorporating unstable solutions in the lock-in region are also obtained. In addition, the effects of two kinds of fluctuating lift coefficients on the steady-state responses are compared with each other.

关键词： pipes conveying fluid vortex-induced vibration lock-in steady-state responses fluctuat-ing lift

Insight into the role of iron in platinum-based bimetallic catalysts for selective hydrogenation of cinnamaldehyde

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Chinese Chemical Letters 2022年第8期33卷 3757-3761页

作者： Ying Zhang Jinfang Su Junnan Chen Chengshan dai Bingsen Zhang Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China School of Petrochemical Engineering Liaoning Pertochemical UniversityFushun 113001China

Selective hydrogenation of cinnamaldehyde(CAL)toward cinnamyl alcohol(COL)is an extremely important and challenging ***,a series of Pt_(x)Fe_(y)-Al_(2)O_(3) bimetallic catalysts with varied Pt to Fe ratios were prepared by incipient wetness impregnation *** introduction of Fe significantly modifies the electronic and surface properties of Pt,which clearly enhances the C=O hydrogenation *** all the catalysts,Pt_(3)Fe-Al_(2)O_(3) displays the best catalytic performance and the conversion of CAL is 96.6%with 77.2%selectivity of COL within 1 *** addition,Pt_(3)Fe-Al_(2)O_(3) had excellent reusability with 76%COL selectivity after five runs of the recycle *** characterization of the fresh,used and cycled catalysts revealed that the structure and electronic state of the synthesized Pt_(x)Fe_(y)-Al_(2)O_(3) are unchanged after hydrogenation *** identical-location transmission electron microscopy(ILTEM)results revealed that the interaction between the nanoparticles and the supports was strong and the catalyst was relatively stable.

关键词： Pt_(x)Fe_(y)NPs Cinnamaldehyde Hydrogenation Chemoselective IL-TEM

Blade-coating Perovskite Films with Diverse Compositions for Efficient Photovoltaics

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Energy & Environmental Materials 2021年第3期4卷 277-283页

作者： Jun-Xing Zhong Wu-Qiang Wu Liming Ding dai-Bin Kuang MOE Key Laboratory of Bioinorganic and Synthetic Chemistry Lehn Institute of Functional MaterialsSchool of ChemistrySun Yat-sen UniversityGuangzhou 510275China Center for Excellence in Nanoscience(CAS) Key Laboratory of Nanosystem and Hierarchical Fabrication(CAS)National Center for Nanoscience and TechnologyBeijing 100190China

In this research highlight,recent significant advances with hot-assisted blade-coating or air knife-assisted blade-coating of different perovskite compositions with bandgaps ranging from 1.3 eV to 1.9 eV(*** or small-bandgap perovskites with mixed cations and anions,2D/3D perovskites,Pb/Sn binary perovskites,and all-inorganic perovskites)for single-junction or tandem PSCs are discussed,with an emphasis on elucidating the distinct ink formulation engineering strategies,crystal growth mechanisms,crystallization kinetics,and optoelectronic properties of the different perovskite compositions.

关键词： perovskite solar cells blade-coating composition engineering bandgaps power conversion efficiencies

Enhanced electrochemical stability of carbon-coated antimony nanoparticles with sodium alginate binder for sodium-ion batteries

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Progress in Natural Science:Materials International 2018年第2期28卷 205-211页

作者： Jianmin feng Liqun Wang Dejun Li Pengyi Lu feng Hou Ji Liang Energy and Materials Engineering Center Institute of Physics and Materials Science Tianjin Normal University Key Laboratory of Advanced Ceramics and Machining Technology of Ministry of Education School of Materials Science and Engineering Tianjin University Institute for Superconducting & Electronic Materials (ISEM) Australian Institute of Innovative Materials (AIIM) University of Wollongong Innovation Campus

The poor cycling stability of antimony during a repeated sodium ion insertion and desertion process is the key issue, which leads to an unsatisfactory application as an anode material in a sodium-ion battery. Addressed at this, we report a facile two-step method to coat antimony nanoparticles with an ultrathin carbon layer of few nanometers（denoted Sb@C NPs） for sodium-ion battery anode application. This carbon layer could buffer the volume change of antimony in the charge-discharge process and improve the battery cycle ***, this carbon coating could also enhance the interfacial stability by firmly connecting the sodium alginate binders through its oxygen-rich surface. Benefitted from these advantages, an improved initial discharge capacity(788.5 mA h g;) and cycling stability capacity（553 mA hg-1 after 50 times cycle） have been obtained in a battery using Sb@C NPs as anode materials at 50 mA g;.

关键词： Sodium-ion battery Antimony Sodium alginate Liquid-phase reduction Carbon coating

购买服务、精英下沉与城市基层治理--基于上海市M区“法律服务进村居”项目的研究

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东北大学学报（社会科学版） 2020年第6期22卷 59-67页

作者：戴康汤峰上海交通大学国际与公共事务学院上海200030 清华大学社会科学学院北京100084

城市基层是攸关社会治理共同体建设的核心空间与关键平台。在城市基层运用政府购买服务政策来加强社会治理,可以补缀行政主导与社会自治范式的不足之处。基于上海市M区“法律服务进村居”项目的个案考察发现,通过购买服务的组合引领机制... 详细信息

城市基层是攸关社会治理共同体建设的核心空间与关键平台。在城市基层运用政府购买服务政策来加强社会治理,可以补缀行政主导与社会自治范式的不足之处。基于上海市M区“法律服务进村居”项目的个案考察发现,通过购买服务的组合引领机制,独立自主的第三方社会精英下沉参与基层治理。在内容上,精英下沉的政策文本主要包括基层自治的嵌入参与、民众需求的服务供给以及社会矛盾的技术治理。在效用上,购买服务引领精英下沉主要通过强化行政吸纳能力、培育“市场经纪机制”、推进“国家趋近社会”三重逻辑来实现城市基层的有效治理。未来的城市治理中,政治场域需要完善政府购买服务政策,支持多元主体参与社会治理,最终在城市基层空间中落实精细化治理的目标。

关键词：购买服务精英下沉法律顾问基层治理

Random Boundary Simulation of Pumping Groundwater on Two-layer Soft Soil Structure with Porous Media

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Journal of Wuhan University of Technology(Materials Science) 2002年第2期17卷 66-69页

作者：管昌生 ZHOUJia-ze PENGShao-min JIANGCang-ru WuhanUniversityofTechnology WuhanInstituteofScienceandTechnology

Based on random theory, fluid dynamics , porous media and soil mechanics, the porosity and random characteristic of the two-layer soft soil in Wuhan region were studied in this paper. The random seepage coefficient on the two-layer soft soil was analyzed, and the seepage model and its random distribution Junction mere given. The groundwater flow differential equations related to the two layer soft soil structure were also established. The evaluation procedure of effect boundary on the pumping water in deep foundation pit was put forward. Moreover , with an engineering example, the probability distribution on random boundary prediction for pumping water of foundation pit was computed.

关键词： groundwater random simulation seepage parameter deep foundation pit

Collision-induced Rotational Energy Transfer in an Atom-Diatom System

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Chinese Journal of Chemical Physics 2008年第5期21卷 457-462页

作者： Yan-qing Ni Jian Li feng-cai Ma Department of Physics Liaoning University Shenyang 110036 China Department of Science Shenyang Institute of Aeronautical Engineering Shengyang 110036 China

As a further theoretical study of the collision-induced quantum interference on rotational energy transfer in an atom-diatom system, based on the first-Born approximation of time-dependent perturbation theory, taking into account the anisotropic Lennard-Jones interaction potential and the long-range interaction potential, the differential interference angles in singlet-triplet mixed states of CO A^1Π（v=9）-e3∑-（v=1） system in collision with He, Ne, Ar, and other partners were calculated theoretically. The relationships of differential interference angle versus impact parameters, including collision parameter b and velocity, are obtained.

关键词： Rotational energy transfer Collision-induced quantum interference Interference angle

COMPARISON ON REFINEMENT OF IRON POWDER BY BALL MILLING ASSISTED BY DIFFERENT EXTERNAL FIELDS

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Acta Metallurgica Sinica(English Letters) 2006年第6期19卷 411-417页

作者： L.Y.dai B.Cao M.Zhu School of Mechanical Engineering South China University of TechnologyGuangzhou 510640China Marine Engineering Institute Jimei UniversityXiamen 361021China

The cryogenic milling and milling in conjunction with dielectric barrier discharge plasma (DBDP) have been separately set up. The combined effect of low temperature and plasma on ball milling has been investigated by examining the refinement of particle size and grain size of iron powder using scanning electron microscopy, X-ray diffraction, and small angle X-ray scattering. It was found that the mean size of iron particles could reach 104nm only after 10 hours of ball milling in conjunction with DBDP, whereas a minimum average grain size of 8.4nm was obtained by cryomilling at -20℃; however, it is difficult to refine the particle size and grain size under the same milling condition in the absence of DBDP and cryogenic temperature.

关键词： ball milling cryomilling dielectric barrier discharge (DBD) nanoparticle