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Variable-Flux Outer-Rotor Permanent Magnet Synchronous Motor for In-Wheel Direct-Drive Applications

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Chinese Journal of Electrical Engineering 2018年第1期4卷 28-35页

作者： Yaojing Feng Fang Li Shoudao Huang ning Yang College of Electrical and Information Engineering Hunan UniversityChangsha 410082China

In-wheel direct-drive is the most efficient driving mode for electric vehicles,and it is the trend for applications in the *** this paper,a novel variable-flux outer-rotor permanent magnet synchronous motor with a hybrid magnetic structure design is *** to the hybrid magnetic pole with Nd-Fe-B and Al-Ni-Co permanent magnet(PM),the air-gap flux can be adjusted by changing the magnetization states of Al-Ni-Co PM,which is beneficial to realize a wide range of speeds and loads from the electromagnetic structure ***,basic structure features of the motor and the flux-adjusting principle are *** design and calculation method of the PM dimensions is derived based on magnetic circuit *** the Preisach hysteresis model of Al-Ni-Co PM is described and is adopted to analyze the motor performance with the coupling of the time step finite element method(FEM),and the magnetization are ***,the operational performance of the proposed motor is obtained by simulation,which verifies the design.

关键词： Outer-rotor permanent magnet synchronous motor variable flux in-wheel direct-drive magnetization finite element method

Microstructure, mechanical properties, and corrosion resistance of Mg–9Li–3Al–1.6Y alloy

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Rare Metals 2016年第5期35卷 374-379页

作者： Hao-miao Yang Nan-Yi Zhang Na Liu Wei-Dong Xie Xiao-Dong Peng College of materials Science and Engineering Chongqing University School of Physics & Electron Engineering Yangtze Normal University

Mg–9Li–3Al–1.6Y alloys were prepared through mixture method. The microstructure, mechanical properties, and corrosion resistance of the as-cast and asextruded alloys were studied by optical microscopy（OM）,scanning electronic microscopy（SEM）, X-ray diffraction（XRD）, mechanical properties testing, and electrochemical measurement. The as-cast Mg–9Li–3Al–1.6Y alloy with the average grain size of 325 lm is composed of b-Li matrix, block a-Mg, and granule Al2Y phases. After extrusion, the grain size of the as-cast alloy is obviously refined and reaches to 75 lm; the strength and elongation of the extruded alloy are enhanced by 17.20 % and49.45 %, respectively, owing to their fine microstructure and reduction of casting defects. The as-extruded alloy shows better corrosion resistance compared to the as-cast one, which may be related to the low stored energy and dislocation density in the extruded alloy, also the homogenization treatment before extrusion.

关键词： Magnesium alloy Microstructures Mechanical properties Corrosion resistance

Enhanced soil moisture improves vegetation growth in an arid grassland of Inner Mongolia Autonomous Region, China

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Journal of Arid Land 2023年第7期15卷 871-885页

作者： ZHANG Hui Giri R KATTEL WANG Guojie CHUAI Xiaowei ZHANG Yuyang miao Lijuan School of Geographical Sciences Nanjing University of Information Science&TechnologyNanjing 210044China State Key Laboratory of Remote Sensing Science Aerospace Information Research InstituteChinese Academy of SciencesBeijing 100094China Department of Infrastructure Engineering the University of MelbourneMelbourne 3010Australia School of Geography&Ocean Science Nanjing UniversityNanjing 210093China

Climate change impacts on grasslands that cover a quarter of the global land area, have become unprecedented during the 21~(st) century. One of the important ecological realms, arid grasslands of northern China, which occupy more than 70% of the region's land area. However, the impact of climate change on vegetation growth in these arid grasslands is not consistent and lacks corresponding quantitative research. In this study, NDVI(normalized difference vegetation index) and climate factors including temperature, precipitation, solar radiation, soil moisture, and meteorological drought were analyzed to explore the determinants of changes in grassland greenness in Inner Mongolia Autonomous Region(northern China) during 1982–2016. The results showed that grasslands in Inner Mongolia witnessed an obvious trend of seasonal greening during the study period. Two prominent climatic factors,precipitation and soil moisture accounted for approximately 33% and 27% of grassland NDVI trends in the region based on multiple linear regression and boosted regression tree methods. This finding highlights the impact of water constraints to vegetation growth in Inner Mongolia's grasslands. The dominant role of precipitation in regulating grassland NDVI trends in Inner Mongolia significantly weakened from 1982 to 1996, and the role of soil moisture strengthened after 1996. Our findings emphasize the enhanced importance of soil moisture in driving vegetation growth in arid grasslands of Inner Mongolia, which should be thoroughly investigated in the future.

关键词： grassland growth normalized difference vegetation index climate change soil moisture Inner Mongolia

Deformation patterns and hydrocarbon potential related to intracratonic strike-slip fault systems in the east of Central Uplift Belt in the Tarim Basin

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Energy Geoscience 2022年第1期3卷 63-72页

作者： Fei ning Jinbiao Yun Zhongpei Zhang Peng Li Laboratory of Structural and Sedimentological Reservoir Geology Exploration&Production Research InstituteSINOPECBeijing100083China Exploration&Production Research Institute SINOPECBeijing100083China Geology and Geophysics Department University of Wyoming82071USA

Strike-slip faults,proven to be closely linked to hydrocarbon migration and accumulation,are wide-spread in the Tarim Basin *** patterns in the eastern part of the Central Uplift Belt of the Tarim Basin are analyzed in detail to understand the deformation model and genetic mechanism of strike-slip faults,how their patterns impact reservoir formation and influence oil and gas *** tectonic events are taken into consideration to identify the primary factors that controlled the development of strike-slip faults in the *** Tazhong Uplift in the eastern part of Central Uplift Belt is believed to be a complex anticlinal uplift formed by compression-and-torsion acting on the Cambrian-Middle Ordovician platform during the middle-late Caledonian ***-stage development of this north-trending fault-fold belt and the NE-trending strike-slip faults make it structurally *** NE-trending Paleozoic strike-slip faults were formed jointly by the differential thrusting of the Tazhong Uplift along Fault No.Ⅰand the NE-trending shear sliding of the basal fault blocks during the middle-late Caledonian-early *** on the distribution of effective source rocks,the tectonic setting during the period critical to hydrocarbon accumulation,and the distribution of conductive faults,the northern slope of the Tazhong Upliftd-especially its west-central part where the NE-trending faults are developed is not only located close to the northern hydrocarbon source rock area but also possesses conditions suitable for the development of carbonate *** addition,the NE-trending faults provide passage for initial development of the reservoir and the subsequent migration of oil and gas from the Aman area to the uplifted zone,making the Tazhong Uplift an extremely favorable area for oil and gas accumulation with substantial potential for exploration.

关键词： Strike-slipfault Deformation pattern Hydrocarbon accumulation Craton Tarim basin

Propagation Characteristics of Plane Explosion Wave in Layered Concrete Media

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兵工学报 2015年第S1期36卷 228-232页

作者： DONG Yong-xiang SONG Qi LU Zhi-chao CUI miao FENG Shun-shan State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology

Layered concrete media with different wave impedance materials under one-dimensional strain are studied by numerical simulation. The four typical prototypes are analyzed,including concrete foam,air,steel plate and concrete as the middle layer,and the upper and lower layers are concrete materials. The propagation characteristics of plane blast wave in the concrete structure are illustrated,including the propagation and attenuation of stress wave across the different interlayers,the wave reflection and transmission at layered interfaces,the peak value of stress in the lower concrete and the total energy distribution in various medium layers. The result shows that the role of soft interlayer in concrete structure is mainly due to its low wave impedance,the waveform of incident wave is changed,the stress wavelength is pull wide,the radial diffusion of energy is enhanced,and the stress amplitude of and the energy input into the third layer are reduced. Meanwhile,it has been also proved that the air interlayer is able to reduce the peak value of explosion wave which is obviously different from that of foamed material. As a result,it should be concerned about stress amplitude and energy in order to get the best protective structure.

关键词： explosion wave layered concrete wave impedance numerical simulation

Synthesis of cobalt-doped ZnO/rGO nanoparticles with visible-light photocatalytic activity through a cobalt-induced electrochemical method

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Journal of Energy Chemistry 2017年第3期26卷 549-555页

作者： Yuanquan miao Xuewen Wang Wuyou Wang Chengxi Zhou Gang Feng Jianxin Cai Rongbin Zhang The Institute of Applied Chemistry The College of ChemistryNanchang UniversityNanchang 330031JiangxiChina School of Resources Environmental&Chemical Engineering Nanchang UniversityNanchang 330031JiangxiChina

ZnO is a semiconductor photocatalyst widely applied in photodegradation of organic pollutants and in photoelectric conversion. ZnO exhibits low photocatalytic activity due to poor absorption in the visible region. In this work, a novel cobalt-induced electrochemical growth method was developed to synthesize cobalt-doped ZnO/rGO nanoparticles in an aqueous solution at room temperature. Cobalt-doped ZnO/rGO nanoparticles exhibited wider visible-light absorption band ranging from 400 nm to 700 nm due to cobalt doping. The surface structure of ZnO formed by the cobalt-induced electrochemical method without other ions is suitable for photocatalytic reactions. The cobalt-doped ZnO/rGO nanoparticles were found to exhibit in photodegradation and photo-electrochemical measurements and exhibited enhanced photocatalytic activity under visible-light irradiation.

关键词： Co-doped ZnO Electrochemical Photodegradation Photocatalysis

Role of integrin b1 and tenascin C mediate TGF-SMAD2/3 signaling in chondrogenic differentiation of BMSCs induced by type I collagen hydrogel

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Regenerative Biomaterials 2024年第5期3卷 59-73页

作者： Yuanjun Huang miao Sun Zhenhui Lu Qiuling Zhong Manli Tan Qingjun Wei Li Zheng Guangxi Engineering Center in Biomedical Materials for Tissue and Organ Regeneration The First Affiliated Hospital of Guangxi Medical UniversityGuangxi Medical UniversityNanning 530021China Collaborative Innovation Centre of Regenerative Medicine and Medical BioResource Development and Application Co-Constructed by the Province and Ministry First Affiliated Hospital of Guangxi Medical UniversityGuangxi Medical UniversityNanning 530021China Department of Trauma Orthopedic and Hand Surgery The First Affiliated Hospital of Guangxi Medical UniversityNanning 530021China Guangxi Key Laboratory of Regenerative Medicine The First Affiliated Hospital of Guangxi Medical UniversityGuangxi Medical UniversityNanning 530021China Life Science Institute Guangxi Medical UniversityNanning 530021China

Cartilage defects may lead to severe degenerative joint *** engineering based on type I collagen hydrogel that has chondrogenic potential is ideal for cartilage ***,the underlying mechanisms of chondrogenic differentiation driven by type I collagen hydrogel have not been fully ***,we explored potential collagen receptors and chondrogenic signaling pathways through bioinformatical analysis to investigate the mechanism of collagen-induced *** showed that the super enhancer-related genes induced by collagen hydrogel were significantly enriched in the TGF-b signaling pathway,and integrin-b1(ITGB1),a receptor of collagen,was highly expressed in bone marrow mesenchymal stem cells(BMSCs).Further analysis showed genes such as COL2A1 and Tenascin C(TNC)that interacted with ITGB1 were significantly enriched in extracellular matrix(ECM)structural constituents in the chondrogenic induction *** of ITGB1 led to the downregulation of cartilage-specific genes(SOX9,ACAN,COL2A1),SMAD2 and TNC,as well as the downregulation of phosphorylation of SMAD2/*** of TNC also resulted in the decrease of cartilage markers,ITGB1 and the SMAD2/3 phosphorylation but overexpression of TNC showed the opposite ***,in vitro and in vivo experiments confirmed the involvement of ITGB1 and TNC in collagen-mediated chondrogenic differentiation and cartilage *** summary,we demonstrated that ITGB1 was a crucial receptor for chondrogenic differentiation of BMSCs induced by collagen *** can activate TGF-SMAD2/3 signaling,followed by impacting TNC expression,which in turn promotes the interaction of ITGB1 and TGF-SMAD2/3 signaling to enhance *** may provide concernful support for cartilage tissue engineering and biomaterials development.

关键词： collagen hydrogel chondrogenic induction integrin b1 tenascin C TGF-SMAD2/3 signaling

SW-Net: A novel few-shot learning approach for disease subtype prediction

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BIOCELL 2023年第3期47卷 569-579页

作者： YUHAN JI YONG LIANG ZIYI YANG ning AI Faculty of Innovation Engineering School of Computer Science and EngineeringMacao University of Science and TechnologyMacao999078China Tencent Quantum Lab Shenzhen518000China

Few-shot learning is becoming more and more popular in many fields,especially in the computer vision *** inspires us to introduce few-shot learning to the genomic field,which faces a typical few-shot problem because some tasks only have a limited number of samples with *** goal of this study was to investigate the few-shot disease sub-type prediction problem and identify patient subgroups through training on small *** disease subtype classification allows clinicians to efficiently deliver investigations and interventions in clinical *** propose the SW-Net,which simulates the clinical process of extracting the shared knowledge from a range of interrelated tasks and generalizes it to unseen *** model is built upon a simple baseline,and we modified it for genomic *** initialization for the classifier and transductive fine-tuning techniques were applied in our model to improve prediction accuracy,and an Entropy regularization term on the query set was appended to reduce ***,to address the high dimension and high noise issue,we future extended a feature selection module to adaptively select important features and a sample weighting module to prioritize high-confidence *** on simulated data and The Cancer Genome Atlas meta-dataset show that our new baseline model gets higher prediction accuracy compared to other competing algorithms.

关键词： Few-shot learning Disease sub-type classification Feature selection Deep learning Meta-learning

Investigation of Wellbore Temperature Dynamics during Cement Setting in Deepwater Shallow Formations

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Fluid Dynamics & Materials Processing 2024年第12期20卷 2927-2939页

作者： Jing Li Bo ning Bin Li Dezhi Qiu Guangzhou Marine Geological Survey China Geological SurveyGuangzhou510075China

Offshore deepwater cementing generally faces more challenges than onshore *** formations in deepwater wells often exhibit low structural strength,high porosity,and are prone to shallow gas influx and hydrate *** factors require careful control of hydration *** this article,we examine the key factors influencing temperature fluctuations in the wellbore and develop a temperature model that accounts for the thermal effects related to cement slurry circulation and *** model is then applied to a deepwater shallow formation cementing case *** results show that:(1)When cement slurry is displaced into deep-water shallow formations,it loses heat due to seawater-induced cooling before entering the *** lowers the temperature of both the slurry and the wellbore before cement hydration begins.(2)The main production of heat due to cement hydration occurs during the pre-induction and acceleration *** are also the critical phases that affect formation temperature in deep-water shallow formation *** to Kutasov’s semi-analytical equation,the peak heat release happens 8–12 h after cementing,resulting in a temperature rise of up to 40℃ and 30℃ for 26″and 12-1/4″boreholes,respectively.

关键词： Deep-water shallow strata cementing wellbore circulation temperature heat of cement hydration