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Eruption of an Active-Region Filament Driven by an Emerging Bipole

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Chinese Journal of Astronomy and Astrophysics 2007年第1期7卷 129-140页

作者： Yun-Chun Jiang Yuan-deng shen Jing-Xiu Wang National Astronomical Observatories / Yunnan Observatory Chinese Academy of Sciences Kunming 650011 National Astronomical Observatories Chinese Academy of Sciences Beijing 100012

A section of an S-shaped filament underwent an eruption in a sigmoidal active region （AR 8027） with S-shaped coronal structure, which was clearly driven by a bipole emerging below the NW end of the filament. The bipole with two separating poles showed typical characteristics of emerging flux region （EFR） and its axis rotated counterclockwise. Two canceiling magnetic features （CMFs） were formed between the two poles and adjacent flux with opposite polarity and substantial flux cancellation occurred in them. Along with the bipole emergence the filament was strongly disturbed. Just before the filament eruption, two X-ray loops overlying the filament brightened, an axial X-ray structure and then a cusp structure appeared. During the eruption first the whole filament rose and then its SE end broke away from the chromosphere, while its NW end remained stationary. Helical structure and motion were observed in the filament body and downward mass motion in the two ends. After the eruption, a major part of the filament remained and slowly returned to quiescence, and an X-ray arcade and an axial structure formed. These observations suggest that the eruption resuited from the interaction between the bipole and the overlying loops. We provide evidence that steady photospheric reconnection between their footprints took place in the two CMFs during the bipole emergence.

关键词： Sun: filaments-Sun flares-Sun magnetic fields-Sun corona-Sun X-rays

Preparation of sulphonate-containing core/shell latex particles via seeded emulsion copolymerization

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Chinese Chemical Letters 2010年第10期21卷 1259-1262页

作者： Ji Shuai Wang Wei deng Yun shen Chen Cheng You Kan Department of Chemical Engineering and Key Laboratory of Advanced Materials of Ministry of Education Tsinghua University Belting 100084 China

In this study, P（St-MAA） seed latex particles were first prepared via soap-free emulsion polymerization of styrene （St） and methacrylic acid （MAA）, then the seed particles were allowed to swell with St at room temperature, and the P（St-MAA）/P（St- NaSS） core/shell latex particles were then synthesized via seeded emulsion copolymerization of St and sodium styrene sulphonate （NaSS） using AIBN as initiator in the presence of N,N^-methylenebisacrylamide （BAA, water-soluble crosslinker）. Results showed that the polymerization could be carried out smoothly when the ratio of BAA to total monomers was less than 3 mol%, the narrow dispersed P（St-MAA） seed particles with the diameter of 150 nm and the P（St-MAA）/P（St-NaSS） core/shell latexes with the particle size of about 200 nm were synthesized. When the 25/75 mole ratio of NaSS/（St ＋ MAA） and 2 tool% of BAA were used in the seeded emulsion polymerization, the resulted P（St-MAA）/P（St-NaSS） latex product showed a low weight loss after water extraction, and the NaSS unit content in the whole particle and in the shell reached 11.7 mol% and 34.6 mol%, resoectivelv.

关键词： seeded emulsion polymerization Sulphonate-containing particles Sodium styrene sulphonate N,N^-Methylenebisacrylamide

Preface to the“Theory and Applications of Flexoelectricity”Special Issue of Acta Mechanica Solida Sinica

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Acta Mechanica Solida Sinica 2024年第4期37卷 519-520页

作者： Qian deng Yue Zheng shengping shen School of Aerospace Engineering Huazhong University of Science and TechnologyWuhan430074China School of Physics Sun Yat-sen UniversityGuangzhou510275China School of Aerospace Engineering Xi’an Jiaotong UniversityXi’an710049China

Flexoelectricity refers to the electric polarization generated by non-uniform mechanical strains within dielectric materials and *** intriguing effect bridges the fields of materials science,mechanical engineering,and applied physics,offering a promising avenue for innovation in sensor technology,energy harvesting,multiphysics field coupling,among others.

关键词： offering bridges harvesting

Absolute pose estimation of UAV based on large-scale satellite image

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Chinese Journal of Aeronautics 2024年第6期37卷 219-231页

作者： Hanyu WANG Qiang shen Zilong deng Xinyi CAO Xiaokang Wang School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing 401120China

Obtaining absolute pose based on pre-loaded satellite images is one of the important means of autonomous navigation for small Unmanned Aerial Vehicles(UAVs)in Global Navigation Satellite System(GNSS)denied *** of the previous works have tended to build Convolutional Neural Networks(CNNs)to extract features and then directly regress the pose,which will fail when solving the challenges caused by the huge viewpoint and size differences between“UAV-satellite”image pairs in real-world ***,this paper proposes a probability distribution/regression integrated deep model with the attention-guided triple fusion mechanism,which estimates discrete distributions in pose space and three-dimensional vectors in translation *** order to overcome the shortage of the relevant dataset,this paper simulates image datasets captured by UAVs with forward-facing cameras during target searching and autonomous *** effectiveness,superiority,and robustness of the proposed method are verified by simulated datasets and flight tests.

关键词： Satellite imagery Unmanned Aerial Vehicle(UAV) Deep neural networks Vision navigation von Mises-Fisher distribution

Mathematical Modeling of Multi-sized Argon Gas Bubbles Motion and Its Impact on Melt Flow in Continuous Casting Mold of Steel

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Journal of Iron and Steel Research International 2014年第4期21卷 403-407页

作者： Chong-lin LIU Zhi-guo LUO Tao ZHANG shen deng Nan WANG Zong-shu ZOU School of Materials and Metallurgy Northeastern University Technology Center Guangxi Liuzhou Iron and Steel Company

The 3D turbulence k-ε model flow of the steel melt （continuous phase） and the trajectories of individual gas bubbles （dispersed phase） in a continuous casting mold were simulated using an Eulerian-Lagrangian approach. In order to investigate the effect of bubble size distribution, the radii of bubbles are set with an initial value of 0. 1- 2.5 mm which follows the normal distribution. The presented results indicate that, in the submerged entry nozzle （SEN）, the distribution of void fraction is only near the wall. Due to the fact that the bubbles motion is only limited to the wall, the deoxidization products have no access to contacting the wall, which prevents clogging. In the mold, the bubbles with a radius of 0. 25--2.5 mm will move to the top surface. Larger bubbles issuing out of the ports will attack the menis- cus and induce the fluid flows upwards in the top surface near the nozzle. It may induce mold powder entrapment into the mold. The bubbles with a radius of 0.1--0.25 mm will move to the zone near the narrow surface and the wide surface. These small bubbles will probably be trapped by the solidification front. Most of the bubbles moving to the narrow surface will flow with the ascending flow, while others will flow with the descending flow.

关键词： continuous casting bubble multi-sized distribution dispersed phase void fraction

Impact of High Sodium Diet on Neovascularization and Osseointegration around Titanium Implant:An in Vivo and in Vitro Study

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Biomedical and Environmental Sciences 2024年第7期37卷 739-753页

作者： Keyuan Xu Xiaoting Tang Yun Xiang Yiding shen Zhennan deng Pingping Ma Xinkun shen Department of Orthopaedics The Third Affiliated Hospital of Wenzhou Medical University(Ruian People’s Hospital)Wenzhou 325016ZhejiangChina School and Hospital of Stomatology Wenzhou Medical UniversityWenzhou 325027ZhejiangChina

Objective A high sodium(HS)diet is believed to affect bone metabolism *** its impact on osseointegration of titanium(Ti)implants holds significant implications for postoperative dietary management of implanted *** This investigation probed the impact of sodium ions(Na^(+))on neovascularization and osteogenesis around Ti implants in vivo,utilizing micro-computed tomography,hematoxylin and eosin staining,and immunohistochemical ***,in vitro experiments assessed the effects of varied Na^(+)concentrations and exposure durations on human umbilical vein endothelial cells(HUVECs)and MC3T3-E1 *** In vivo,increased dietary sodium(0.8%-6.0%)led to a substantial decline in CD34 positive HUVECs and new bone formation around Ti implants,alongside an increase in inflammatory *** vitro,an increase in Na^(+)concentration(140-150 mmol/L)adversely affected the proliferation,angiogenesis,and migration of HUVECs,especially with prolonged *** MC3T3-E1 cells initially exhibited less susceptibility to high Na^(+)concentrations compared to HUVECs during short-term exposure,prolonged exposure to a HS environment progressively diminished their proliferation,differentiation,and osteogenic *** These findings suggest that HS diet had a negative effect on the early osseointegration of Ti implants by interfering with the process of postoperative vascularized bone regeneration.

关键词： High-sodium Implants Vascularization Osseointegration

Carbon Fiber Breakage Mechanism in Aluminum(Al)/Carbon Fibers(CFs) Composite Sheet during Accumulative Roll Bonding(ARB) Process

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 167-173页

作者：胡淑芬 SUN Zhenzhong shen Fanghua deng Jun 杨卫平杨浩坤 School of Engineering Jiangxi Agricultural UniversityNanchang 330045China School of Mechanical Engineering Dongguan University of TechnologyDongguan 510730China Guangdong-Hong Kong-Macao Joint Laboratory for Neutron Scattering Science and Technology Dongguan 510730China Smart Manufacturing Division Hong Kong Productivity Council78 Tat Chee AvenueHong Kong 5999075China

We put forward a method of fabricating Aluminum(Al)/carbon fibers(CFs) composite sheets by the accumulative roll bonding(ARB) method. The finished Al/CFs composite sheet has CFs and pure Al sheets as sandwich and surface layers. After cross-section observation of the Al/CFs composite sheet, we found that the CFs discretely distributed within the sandwich layer. Besides, the tensile test showed that the contribution of the sandwich CFs layer to tensile strength was less than 11% compared with annealed pure Al sheet. With ex-situ observation of the CFs breakage evolution with-16%,-32%, and-45% rolling reduction during the ARB process, the plastic instability of the Al layer was found to bring shear damages to the CFs. At last, the bridging strengthening mechanism introduced by CFs was sacrificed. We provide new insight into and instruction on Al/CFs composite sheet preparation method and processing parameters.

关键词： Al/CFs composite sheet accumulative roll bonding tensile strength plastic instability carbon fiber breakage

Lightweight Intrusion Detection Using Reservoir Computing

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Computers, Materials & Continua 2024年第1期78卷 1345-1361页

作者： Jiarui deng Wuqiang shen Yihua Feng Guosheng Lu Guiquan shen Lei Cui Shanxiang Lyu Joint Laboratory on Cyberspace Security China Southern Power GridGuangzhou510080China College of Cyber Security Jinan UniversityGuangzhou510632China Guangdong Power Grid Company Limited Guangzhou510663China School of Computer Science and Technology Guangdong University of TechnologyGuangzhou510006China China Southern Power Grid Extra High Voltage Transmission CompanyGuangzhouChina

The blockchain-empowered Internet of Vehicles(IoV)enables various services and achieves data security and privacy,significantly advancing modern vehicle ***,the increased frequency of data transmission and complex network connections among nodes also make them more susceptible to adversarial *** a result,an efficient intrusion detection system(IDS)becomes crucial for securing the IoV *** IDSs based on convolutional neural networks(CNN)often suffer from high training time and storage *** this paper,we propose a lightweight IDS solution to protect IoV against both intra-vehicle and external *** approach achieves superior performance,as demonstrated by key metrics such as accuracy and ***,our method achieves accuracy rates ranging from 99.08% to 100% on the Car-Hacking dataset,with a remarkably short training time.

关键词： Echo state network intrusion detection system Internet of Vehicles reservoir computing

MODELING UNCONFINED SEEPAGE FLOW USING THREE-DIMENSIONAL NUMERICAL MANIFOLD METHOD

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Journal of Hydrodynamics 2010年第4期22卷 554-561页

作者： JIANG Qing-hui deng Shu-shen ZHOU Chuang-bing LU Wen-bo School of Civil Engineering Wuhan University Wuhan 430072 China State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University Wuhan 430072 China

Three-dimensional numerical manifold method for unconfined seepage analysis is proposed in this *** constructing hydraulic potential functions of the manifold element,the element conductivity matrix and the global simultaneous equations for unconfined seepage analysis are derived in *** algorithm of locating the free surface and the formula for seepage forces are also ***-dimensional manifold method employs the tetrahedral mathematical meshes to cover the whole material *** the iterative process for locating the free surface,the manifold method can achieve an accurate seepage analysis of the saturated domain below the free surface with mathematical meshes *** the shape of manifold elements can be arbitrary,the disadvantage of changing the permeability of transitional elements cut by the free surface in the conventional Finite Element Method（FEM） is removed,and the accuracy of locating the free surface can be ***,the seepage force acting on the transitional elements can be accurately calculated by the simplex *** results for a typical example demonstrate the validity of the proposed method.

关键词： three-dimensional seepage numerical manifold method free surface mathematical mesh manifold element