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Study on the Evolution of a Northeast China Cold Vortex during the Spring of 2010

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Atmospheric and Oceanic Science Letters 2014年第2期7卷 149-156页

作者： fu shen-Ming SUN Jian-Hua QI Lin-Lin International Center for Climate and Environment Sciences (ICCES) Institute of Atmospheric Physics Chinese Academy of Sciences Laboratory of Cloud-Precipitation Physics and Severe Storms (LACS) Institute of Atmospheric Physics Chinese Academy of Sciences Institute of Aeronautical Meteorology and Chemical Defense Equipment Academy of Air Force

Based on the final analysis data with horizontal resolution of 1°× 1°(four times a day) from the National Centers for Environmental Prediction(NCEP), a typical Northeast China cold vortex(NCCV) during the spring of 2010 was examined with the quasi-Lagrange- form eddy flux circulation(EFC) budget equation. Results indicated that the mechanisms that account for the development, maintenance, and attenuation of the cyclone varied with levels and stages. Displacement of the cyclone and transports by background environmental circulations dominated the variation of the cyclone in the middle and upper levels, whereas displacement and divergence associated with the cyclone dominated the evolution of the NCCV in the middle and lower levels. Moreover, interactions between the NCCV and other subsynoptic weather systems were important for the development of the cyclone, and the pattern of background environmental circulations was also important for the evolution of the NCCV, since the cyclone enhanced(weakened) as it moved from areas of low(high) vorticity to high(low) ones.

关键词： Northeast China cold vortex quasi-Lagrange-form eddy flux circulation budget

Study on Electronic Conductivity of CaO-SiO2-Al2O3-FeOx Slag System

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Journal of Iron and Steel Research International 2000年第1期7卷 9-13页

作者： LU Xiong-gang LI fu-shen LI Li-fen CHOU Kou-chih University of Science and Technology Beijing Shanghai University

A study on electronic conductivity of CaO-SiO2-Al2O3-FeOxslag system with Wagner polarization technique was carried *** experimental data show that electronic conductivity is consisted of free electron conductivity and electron hole conductivity and both are related to the content of Fe3+and Fe2+.Free electron conductivity is decreasing and electron hole conductivity is increasing while Fe3+changes to Fe2+.There is a maximum electronic conductivity at some ratio of ferric ions Fe3+to total ion *** the experimental conditions,the electronic conductivity is in the range of 10-4—10-2S/cm.

关键词： smelt slag electron hole electronic conductivity

Captioning Videos Using Large-Scale Image Corpus

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Journal of Computer Science & Technology 2017年第3期32卷 480-493页

作者： Xiao-Yu Du Yang Yang Liu Yang fu-Min shen Zhi-Guang Qin Jin-Hui Tang School of Information and Software Engineering University of Electronic Science and Technology of China Chengdu 610054 China School of Software Engineering Chengdu University of Information Technology Chengdu 610225 China Center for future Media University of Electronic Science and Technology of China Chengdu 611731 China School of Computer Science and Engineering University of Electronic Science and Technology of China Chengdu 611731 China Sichuan University West China Hospital of Stomatology Chengdu 610041 China School of Computer Science and Engineering Nanjing University of Science and Technology Nanjing 210094 China

Video captioning is the task of assigning complex high-level semantic descriptions （e.g., sentences or paragraphs） to video data. Different from previous video analysis techniques such as video annotation, video event detection and action recognition, video captioning is much closer to human cognition with smaller semantic gap. However, the scarcity of captioned video data severely limits the development of video captioning. In this paper, we propose a novel video captioning approach to describe videos by leveraging freely-available image corpus with abundant literal knowledge. There are two key aspects of our approach： 1） effective integration strategy bridging videos and images, and 2） high efficiency in handling ever-increasing training data. To achieve these goals, we adopt sophisticated visual hashing techniques to efficiently index and search large-scale images for relevant captions, which is of high extensibility to evolving data and the corresponding semantics. Extensive experimental results on various real-world visual datasets show the effectiveness of our approach with different hashing techniques, e.g., LSH （locality-sensitive hashing）, PCA-ITQ （principle component analysis iterative quantization） and supervised discrete hashing, as compared with the state-of-the-art methods. It is worth noting that the empirical computational cost of our approach is much lower than that of an existing method, i.e., it takes 1/256 of the memory requirement and 1/64 of the time cost of the method of Devlin et al.

关键词： video captioning hashing image captioning

Effects of specific surface area of metallic nickel particles on carbon deposition kinetics

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International Journal of Minerals,Metallurgy and Materials 2018年第2期25卷 226-235页

作者： Zhi-yuan Chen Liu-zhen Bian Zi-you Yu Li-jun Wang fu-shen Li Kuo-Chih Chou Collaborative Innovation Center of Steel Technology University of Science and Technology Beijing Department of Materials Science and Engineering Delft University of Technology State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing School of Materials Science and Engineering University of Science and Technology Beijing

Carbon deposition on nickel powders in methane involves three stages in different reaction temperature ranges. Temperature programing oxidation test and Raman spectrum results indicated the formation of complex and ordered carbon structures at high deposition temperatures. The values of I（D）/I（G） of the deposited carbon reached 1.86, 1.30, and 1.22 in the first, second, and third stages, respectively. The structure of carbon in the second stage was similar to that in the third stage. Carbon deposited in the first stage rarely contained homogeneous pyrolytic deposit layers. A kinetic model was developed to analyze the carbon deposition behavior in the first stage. The rate-determining step of the first stage is supposed to be interfacial reaction. Based on the investigation of carbon deposition kinetics on nickel powders from different resources, carbon deposition rate is suggested to have a linear relation with the square of specific surface area of nickel particles.

关键词： metallic nickel carbon deposition coking specific surface area methane kinetics

Carbon deposition in porous nickel/yttria-stabilized zirconia anode under methane atmosphere

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International Journal of Minerals,Metallurgy and Materials 2019年第3期26卷 350-359页

作者： Zhi-yuan Chen Li-jun Wang Xiao-jia Du Zai-hong Sun fu-shen Li Kuo-Chih Chou State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Department of Materials Science and Engineering Delft University of Technology Collaborative Innovation Center of Steel Technology University of Science and Technology Beijing Suzhou Huatsing Jingkun New Energy Technology Co. Ltd. School of Materials Science and Engineering University of Science and Technology Beijing

A commercial solid oxide fuel cell with a Ni/YSZ anode was characterized under a pure methane atmosphere. The amount of deposited carbon increased with an increase in temperature but decreased when the temperature exceeded 700°C. The reactivity of carbon decreased with increasing deposition temperature. Filamentous carbon was deposited from 400 to 600°C, whereas flake carbon was deposited at 700 and 800°C. With increasing temperature, the intensity ratio of the D band over the sum of the G and D bands was constant at the beginning and then decreased with the transformation of the carbon morphology. The crystallite size increased from 2.9 to 13 nm with increasing temperature. The results also indicated that the structure of the deposited carbon was better ordered with increasing deposition temperature. In comparison with pure Ni powders, the interaction between the YSZ substrate and Ni particles could not only modify the carbon deposition kinetics but also reduce the temperature effect on the structure and reactivity variation of carbon.

关键词： solid oxide fuel cell coking Raman spectrum hydrocarbon fuel anode

Ferucarbotran versus Gd-DTPA-enhanced MR imaging in the detection of focal hepatic lesions

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World Journal of Gastroenterology 2007年第36期13卷 4891-4896页

作者： Wei-Zhong Cheng Meng-Su Zeng fu-Hua Yan shen- Xiang Rao Ji-Zhang shen Cai-Zhong Chen Shu-Jie Zhang Wei-Bin Shi Department of Radiology Zhongshan HospitalFudan University and Department of Medical ImagingShanghai Medical SchoolFudan UniversityShanghai 200032China

AIM: To evaluate the efficacy of ferucarbotran-enhanced MR imaging in the detection of focal hepatic lesions compared to plain and Gd-DTPA-enhanced MR imaging. METHODS: Fifty-nine patients with suspected focal hepatic lesions were admitted to the study. Plain MR imaging (FSE T2WI with fat suppression and GRE T1WI sequences) and Gd-DTPA dynamic enhanced MR of the liver were initially performed followed by ferucarbotran- enhanced MR imaging 48 h later (including GRE T1WI, FSE T2WI with fat suppression, and GRE T2*WI sequences). Images were reviewed independently by three observers. Results were correlated with surgery and pathologic examination or reference examination, and sensitivity was statistically calculated for the different MR imaging sequences. RESULTS: Among all confirmed lesions (n = 133), ferucarbotran-enhanced MR imaging revealed 130 lesions on FSE T2WI with fat suppression, 115 lesions on dynamic T1WI GRE, and 127 lesions on GRE T2*WI. Pre-contrast MR imaging revealed only 84 lesions on GRE T1WI and 106 lesions on FSE T2WI with fat suppression, while Gd-DTPA dynamic enhanced GRE T1WI revealed 123 lesions. For 44 micro-lesions (< 1.0 cm) in all patients the detection rates were as follows: ferucarbotran-enhanced FSE T2WI with fat suppression, 93.2% (41/44); ferucarbotran-enhanced GRE T2*WI, 88.6% (39/44); Gd-DTPA dynamic-enhanced GRE T1WI, 79.5% (35/44); pre-contrast FSE T2WI with fat suppression, 54.5% (24/44); and pre-contrast GRE T1WI, 34.1% (15/44). In detecting micro-lesions, statistically significant difference was found for Ferucarbotran- enhanced FSE T2WI with fat suppression and GRE T2*WI sequences compared to the other sequences (P < 0.05).CONCLUSION: Ferucarbotran-enhanced FSE T2WI with fat suppression and GRE T2*WI sequences are superior in detecting micro-lesions (< 1 cm) in comparison with plain and Gd-DTPA dynamic-enhanced MR imaging.

关键词： Liver disease Contrast media Superpara- magnetic iron oxide Magnetic resonance imaging

PP2A Inhibits Cervical Cancer Cell Migration by Dephosphorylation of p-JNK,p-p38 and the p-ERK/MAPK Signaling Pathway

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Journal of Huazhong University of Science and Technology(Medical Sciences) 2018年第1期38卷 115-123页

作者： Hong-yun ZHENG fu-jin shen Yong-qing TONG Yan LI Department of Clinical Laboratory Renmin Hospital of Wuhan University Clinical Molecular Diagnostic Center Renmin Hospital of Wuhan University Department of Gynecology Renmin Hospital of Wuhan University

Protein phosphatase 2 A（PP2 A） was reported to play an important role in cancer development;however,the relationship between PP2 A and cervical cancer development has yet to be fully *** present study aimed to explore the role of PP2 A in the development of cervical *** levels of PP2 A were detected by ELISA in 23 patients with cervical cancer and 30 patients with benign cervical ***,the PP2 A activities and the m RNA and protein levels of PP2 A were measured in cervical cancer（n=8） and chronic cervicitis（n=10） *** results showed that the serum levels of PP2 A were significantly reduced in patients with cervical *** studies showed that not only the activities of PP2 A but also the m RNA and protein levels of PP2 A were significantly decreased in cervical cancer *** healing and Transwell assays demonstrated that pharmacological and genetic upregulation of PP2 A could inhibit the migration of He La cells,but the downregulation of PP2 A promoted cellular *** activation of PP2 A also inhibited the remodeling of actin and the activity of mitogen-activated protein kinases（MAPKs） including p-JNK,p-p38 and ***,the activation of PP2 A was found to downregulate MMP-9 levels,which further inhibited the migration and invasion of He La *** conclusion,our data suggest that the activity and expression of PP2 A are significantly reduced in cervical cancer tissues,and the activation of PP2 A may inhibit the migration of cervical cancer cells by inhibiting the phosphorylation of p-JNK,p-p38 and the p-ERK/MAPK signaling pathway as well as by downregulating MMP-9,implying that PP2 A plays an important role in cervical cancer development.

关键词： protein phosphatase 2A HeLa cells migration mitogen-activated protein kinases

Post-Treatment Techniques for Enhancing Mode-Coupling in Long Period Fiber Gratings Induced by CO2 Laser

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Photonic Sensors 2015年第4期5卷 339-344页

作者： Xizhen XU Jian TANG Jing ZHAO Kaiming YANG Cailing fu Qiao WANG shen LIU Changrui LIAO Jiarong LIAN Yiping WANG Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province ShenzhenUniversity Shenzhen 518060 China

Two promising post-treatment techniques, i.e. applying tensile strain and rising temperature, are demonstrated to enhance the mode-coupling efficiency of the CO2-1aser-induced long period fiber gratings （LPFGs） with periodic grooves. Such two post-treatment techniques can be used to enhance the resonant attenuation of the grating to achieve a LPFG-based filter with an extremely large attenuation and to tailor the transmission spectrum of the CO2-1aser-induced LPFG after grating fabrication.

关键词： Long period fiber gratings fiber Bragg gratings optical fiber sensor temperature tensile strain opticalfiber device.

Study on the Dynamic Characteristics of an Eastward-offshore Mesoscale Vortex along the Meiyu-Baiu Front

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Atmospheric and Oceanic Science Letters 2012年第5期5卷 360-366页

作者： YU Fei fu shen-Ming ZHAO Si-Xiong SUN Jian-Hua International Center for Climate and Environment Sciences Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

The eastward-moving Meiyu-Baiu frontal mesoscale vortices (MBFMVs) appear frequently and often cause heavy rainfall events along their tracks. A move-off-shore MBFMV was selected to enhance our understanding of this type of vortex. Synoptic analyses indicate that the MBFMV is a type of meso-α vortex and mainly occurs in the lower troposphere. A short wave trough near the coastline is highly favorable for the formation, sustainment, and displacement of the MBFMV. Vorticity budgets indicate that at lower levels of the MBFMV, convergence is the dominant factor for the increase of positive vorticity, and at high levels of the MBFMV, the vertical transportation associated with convective activities is the most important factor. The hori-zontal transportation was the main factor decreasing the positive vorticity. The land and sea environments are crucial to the evolution of the MBFMV. The characteristics of the Meiyu-Baiu Front (MBF) are also vital to the variation of the vortex.

关键词： Meiyu-Baiu Front mesoscale vortex vortic-ity budget