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Fault Diagnosis Based on Interpretable Convolutional Temporal-spatial Attention Network for Offshore Wind Turbines

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Journal of Modern Power Systems and Clean Energy 2024年第5期12卷 1459-1471页

作者： Xiangjing Su chao Deng Yanhao shan Farhad Shahnia Yang Fu Zhaoyang Dong the Engineering Research Center of Offshore Wind Technology Ministry of Education Shanghai University of Electric PowerShanghai 200090China the Offshore Wind Power Research Institute Shanghai University of Electric PowerShanghai 200090China the Yantai Power Supply Company State Grid Shandong Electric Power Co.Ltd.Yantai 264001China the School of Engineering and Energy Murdoch UniversityPerth WA 6150Australia the School of Electrical and Electronic Engineering Nan yang Technological UniversitySingapore 639798Singapore

Fault diagnosis(FD)for offshore wind turbines(WTs)are instrumental to their operation and maintenance(O&M).To improve the FD effect in the very early stage,a condition monitoring based sample set mining method from supervisory control and data acquisition(SCADA)time-series data is ***,based on the convolutional neural network(CNN)and attention mechanism,an interpretable convolutional temporal-spatial attention network(CTSAN)model is *** proposed CTSAN model can extract deep temporal-spatial features from SCADA time-series data sequentially by:(1)a convolution feature extraction module to extract features based on time intervals;(2)a spatial attention module to extract spatial features considering the weights of different features;and(3)a temporal attention module to extract temporal features considering the weights of *** proposed CTSAN model has the superiority of interpretability by exposing the deep temporal-spatial features extracted in a human-understandable form of the temporal-spatial attention *** effectiveness and superiority of the proposed CTSAN model are verified by real offshore wind farms in China.

关键词： Offshore wind turbine(WT) gearbox fault diagnosis(FD) attention mechanism interpretability temporal-spatial feature

Soldering of Zr-based bulk metallic glass and copper by Au-12Ge eutectic alloy

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Rare Metals 2019年第1期38卷 52-58页

作者： Jun Wang Jing Cui Hong-chao Kou Heng Guan Jin-shan Li State Key Laboratory of Solidification Processing Northwestern Polytechnical University

Zr-based bulk metallic glass and copper with different surface roughness were soldered using low temperature eutectic Au-12 Ge(wt%) solder on a thermomechanical simulator. The cross-sectional microstructures of the brazed joints were analyzed by scanning electron microscopy(SEM) and transmission electron microscope(TEM) in detail, and the compositional distribution along the interface was analyzed by energy-dispersive spectrometer(EDS). Results show that the surface roughness of base metals plays an important role in the quality of the brazed joint because the surface roughness can enlarge the effective contact area, which can improve the brazing surface quality between two materials. A moderate roughness of treated Zr-based metallic glass of 18 μm is shown to be the best for the soldering, while the surface roughness has a weak effect on the soldering behavior of Au-12 Ge solder on copper. After soldering, long-range diffusion of atoms occurs between the base metal and solder, and five distinct regions are formed at the joint region.

关键词： Bulk metallic glass Soldering Au-Ge eutectic alloy Interface

One-dimensional sp carbon:Synthesis,properties,and modifications

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Chinese Physics B 2022年第12期31卷 567-589页

作者： chao-Fan Lv Xi-Gui Yang Chong-Xin shan State Key Laboratory of Luminescence and Applications Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China University of Chinese Academy of Sciences Beijing 100049China Henan Key Laboratory of Diamond Optoelectronic Materials and Devices Key Laboratory of Material PhysicsMinistry of EducationSchool of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450052China

Carbyne,as the truly one-dimensional carbon allotrope with sp-hybridization,has attracted significant interest in recent years,showing potential applications in next-generation molecular devices due to its ultimate one-atom *** excellent properties of carbyne have been predicted,however,free-standing carbyne sample is extremely unstable and the corresponding experimental researches and modifications are under-developed compared to other known carbon *** synthesis of carbyne has been slowly developed for the past ***,there have been several breakthroughs in in-situ synthesis and measurement of carbyne related materials,as well as the preparation of ultra-long carbon chains toward infinite *** progresses have aroused widespread discussion in the academic *** this review,the latest approaches in the synthesis of sp carbon are *** then discuss its extraordinary properties,including mechanical,electronic,magnetic,and optical properties,especially focusing on the regulations of these ***,we provide a perspective on the development of carbyne.

关键词： carbyne polyyne linear carbon chains

Promoting Si-graphite composite anodes with SWCNT additives for half and NCM 811 full lithium ion batteries and assessment criteria from an industrial perspective

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Frontiers in Energy 2019年第4期13卷 626-635页

作者： Jingning shan Xiaofang YANG chao YAN Lin CHEN Fang ZHAO Yiguang JU Department of Mechanical and Aerospace Engineering Princeton University HiT Nano IncPrinceton 08540USA Department of Mechanical and Aerospace Engineering Princeton UniversityPrinceton NJ 08544USA Department of Mechatronics Engineering College of Mechanical EngineeringGuangxi UniversityNanning 530004China Department of Physics Princeton UniversityPrinceton NJ 08544USA

Single wall carbon nanotube(SWCNT)additives were formulated into(im-Si-graphite composite electrodes and tested in both half cells and full cells with high nickel *** critical role of small amount of SWCNT addition(0.2 wt%)was found for significantly improving delithiation capacity,first cycle coulombic efficiency(FCE),and capacity ***,Si(10 wt%)-graphite electrode exhibits 560 mAh/g delithiation capacity and 92%FCE at 0.2 C during the first chargedischarge cycle,and 91%capacity retention after 50 cycles(0.5 C)in a half *** electron microscope(SEM)was used to illustrate the electrode morphology,compositions and promoting function of the SWCNT *** addition,full cells assembled with high nickel-NCM811 cathodes and fim-Si-graphite composite anodes were evaluated for the consistence between half and full cell performance,and the consideration for potential commercial ***,criteria to assess Si-containing anodes are proposed and discussed from an industrial perspective.

关键词： lithium-ion battery Si anode Si-graphite composite single wall carbon nanotube(SWCNT) NCM811

Preliminary analysis on characteristics of coseismic deformation associated with MS=8.1 western Kunlunshan Pass earthquake in 2001

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Acta Seismologica Sinica(English Edition) 2004年第5期17卷 526-533页

作者： shan Xin-jian(单新建) LIU Jia-hang(柳稼航) MA chao(马超) State Key Laboratory of Earthquake Dynamics China Earthquake AdministrationBeijing100029China State Key Laboratory of Earthquake DynamicsChina Earthquake AdministrationBeijing100029China Taiyuan University of TechnologyTaiyuan030024China

Based on the analysis of coseismic deformation in the macroscopic epicentral region extracted by Differential Interferometric Synthetic Aperture Radar (D-InSAR), and combined with the seismic activity, focal mechanism solutions of the earthquake and field investigation, the characteristic of coseismic deformation of MS=8.1 western Kunlunshan Pass earthquake in 2001 was researched. The study shows that its epicenter lies in the northeast side of Hoh Sai Hu; and the seismogenic fault in the macroscopic epicentral region can be divided into two central deformation fields: the west and east segments with the lengths of 42 km and 48 km, respectively. The whole fault extends about 90 km. From the distribution of interferometry fringes, the characteristic of sinistral strike slip of seismogenic fault can be identified clearly. The deformations on both sides of the fault are different with an obviously higher value on the south side. In the vicinity of macroscopic epicenter, the maximum displacement in look direction is about 288.4 cm and the minimum is 224.0 cm; the maximum sinistral horizontal dislocation of seismogenic fault near the macroscopic epicenter is 738.1 cm and the minimum is 551.8 cm.

关键词： InSAR M_S=8.1 western Kunlunshan Pass earthquake coseismic deformation

Encapsulating manganese oxide nanoparticles within conducting polypyrrole via in situ redox reaction and oxidative polymerization for long-life lithium-ion batteries

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Rare Metals 2021年第9期40卷 2415-2423页

作者： He-Liang Yao shan-shan Gao Zheng-Qian Fu Wei-chao Bao Zhong-Hui Cui Yi-Qiu Li Fang-Fang Xu State Key Laboratory of High Performance Ceramics and Superﬁne Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China

Manganese oxides(MnO_(x)) have been extensively investigated due to their extremely high theoretical capacities for application as conversion anodes in lithiumion batteries. However, fully performing their theoretical performance still faces poor electric conductivity and serious volume change upon lithium insertion/***, we demonstrate encapsulating manganese oxide nanoparticles within a conducting polymer polypyrrole(PPy) shell as a facile strategy to overcome such flaws through in situ redox reaction and oxidative polymerization process. Such an in situ method combines the redox reaction between potassium permanganate and tetrahydrofuran to form MnO_(x)nanoparticles and the subsequent oxidative polymerization of pyrrole to form a conductive polypyrrole coating shell by the oxidant KMnO_(4) into one step. For the as-fabricated products(MnO_(x)@PPy), this tenderly introduced conductive PPy shell highly favors the fast electron transfer and preserves the electrode structure integrity upon repeated cycling. As the anode for LIBs, MnO_(x)@PPy exhibits superior lithium storage performance with a high reversible capacity(1538 mAh·g^(-1)), long-life cyclability(747 mAh·g^(-1) after 1000 cycles at 1.0 C) and durable ratability(574 mAh·g^(-1) at 2.0 C). This work demonstrates that the convenient in situ strategy to form conductive polymer coating shell is effective to improve the performance of conversion anodes and can be extended to other materials for energy storage applications.

关键词： Manganese oxide Polypyrrole High cycling performance Lithium-ion battery

Enantioselective and stereodivergent hydromonofluoroalkylation of conjugated and remote diene

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Chinese Chemical Letters 2023年第12期34卷 159-165页

作者： Qi-Ying Liao chao Ma Yu-chao Wang Shao-Qian Yang Jiang-shan Ma Zhi-Tao He College of Chemistry and Materials Science Sichuan Normal UniversityChengdu 610068China CAS Key Laboratory of Synthetic Chemistry of Natural Substances Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesShanghai200032China School of Chemistry and Materials Science Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China

Because of the widespread applications of optically active alkyl fluorides in medicinal and agro chem-icals,enantioselective and even stereodivergent construction of alkyl fluorides remains highly desirable but ***-metal-catalyzed asymmetric hydrofluoroalkylation of readily available di-enes represents a novel route to achieve this goal,yet receives scarce *** we report an intrigu-ing palladium-catalyzed enantioselective hydromonofluoroalkylation reaction of conjugated *** monosubstituted and internal dienes proceed well with the transformation and furnish alkyl fluorides in generally>80%yield and>90%ee.A stereodivergent hydromonofluoroalkylation protocol via Pd/Cu co-catalysis is also established for the access to all four stereoisomers of corresponding moieties bear-ing a fully-substituted F-stereogenic center and vicinal tertiary carbon *** addition,asymmetric migratory hydromonofluoroalkylation of skipped dienes is developed to realize the direct allylic C-H flu-oroalkylation.A compound library of enantioenriched cyclic fluorides is thus built to highlight the trans-formation potential of present methodology.

关键词： Hydromonofluoroalkylation Enantioselective Stereodivergent 1,3-Diene Remote diene

Hot Deformation Behavior of a New Nuclear Use Reduced Activation Ferritic/Martensitic Steel

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Acta Metallurgica Sinica(English Letters) 2019年第7期32卷 825-834页

作者： chao Liu Ming-Chun Zhao Tuguldur Unenbayar Ying-chao Zhao Bin Xie Yan tian Yi-Yin shan Ke Yang School of Material Science and Engineering Central South University Changsha 410083 China Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

The hot deformation behavior and workability of a new reduced activation ferritic/martensitic steel named SIMP steel for accelerator-driven system were studied. The flow curve and its microstructure were studied at 900-1200 ℃ and strain rate range of 0.001-10 s^-1. The results showed that the deformation behavior of the SIMP steel during hot compression could be manifested by the Zener-Hollomon parameter in an exponent-type equation. Based on the obtained constitutive equation, the calculated flow stresses were in agreement with the experimentally measured ones, and the average activity energies Qdrv and QHw for the initiation of dynamic recrystallization and the peak strain were calculated to be 476.1 kJ/mol and 462.7 kJ/mol, respectively. Furthermore, based on the processing maps and microstructure evolution, the optimum processing condition for the SIMP steel was determined to be 1050-1200 ℃/0.001-0.1s^-1.

关键词： Reduced activation ferritic/martensitic steel Hot deformation Flow curve Constitutive equation Processing map

The coseismic displacement field of the Zhangbei-shangyi earthquake mapped by differ-ential radar interferometry

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Chinese Science Bulletin 2001年第6期46卷 514-517,530页

作者： WANG chao LIU Zhi ZHANG Hong shan Xinjian LARSIS of Institute of Remote Sensing Applications Chinese Academy of SciencesBeijing 100101China Institute of Geology Seismology Bureau of ChinaBeijing 100029China

The coscismic deformation produced by 1998 earthquake (M8 = 6.2) in Zhangbei-shangyi of northern China is measured by the differential synthetic aperture radar interferometry (D-InSAR) technique using the European Remote Sensing satellite (ERS) SAR data. Interferograms are constructed from the ERS-1/2 SAR data by the three-pass method. The line-of-sight displacement map indicates that the deformation center of the earthquake is located at E114°20’, N40°57’, with the maximum uplift of 25 cm. The extent of the displacement is around 300 km2. The focal mechanism and earthquake-induced structures are analyzed based on the spatial distribution of the deformation. The results give new insights into the seismic mechanism study.

关键词： synthetic aperture radar (SAR) differential interfero- metric SAR (D-InSAR) Zhangbei earthquake displacement.