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Water Modeling of Optimizing Tundish Flow Field

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Journal of Iron and Steel Research International 2007年第3期14卷 13-19页

作者： LIU jin-gang YAN Hui-cheng LIU Liu WANG Xin-hua Shougang Research Institute of Technology Beijing 100041 China Department of Metallurgical Technology Central Iron and Steel Research Institute Beijing 100081 China Metallurgical and Ecological Engineering School University of Science and Technology Beijing Beijing 100083 China

In the water modeling experiments, three cases were considered, i. e, , a bare tundish, a tundish equipped with a turbulence inhibitor, and a rectangular tundish equipped with weirs （dams） and a turbulence inhibitor. Comparing the RTD curves, inclusion separation, and the result of the streamline experiment, it can be found that the tundish equipped with weirs （dams） and a turbulence inhibitor has a great effect on the flow field and the inclusion separation when compared with the sole use or no use of the turbulent inhibitor or weirs （dams）. In addition, the enlargement of the distance between the weir and dam will result in a better effect when the tundish equipped with weirs （dam） and a turbulence inhibitor was used.

关键词： tundish flow field turbulence inhibitor weir dam water modeling experiment

Motion texture using symmetric property and graphcut algorithm

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第7期7卷 1107-1114页

作者： SHEN Jian-bing jin Xiao-gang ZHOU Chuan ZHAO Han-li State Key Lab of CAD ＆ CG Zhejiang University Hangzhou 310027 China

In this paper, a novel motion texture approach is presented for synthesizing long character motion (e.g., kungfu) that is similar to the original short input motion. First, a new motion with repeated frames is generated by exploiting the symmetric properties of the frames and reversing the motion sequence playback in a given motion sequence. Then, the order of the above motion sequence is rearranged by putting the start and the end frames together. The graphcut algorithm is used to seamlessly synthesize the transition between the start and the end frames, which is noted as graphcut-based motion-texton. Finally, we utilize the motion-textons to synthesize long motion texture, which can be patched together like the image texture synthesis method using graphcut algorithm, and automatically form a long motion texture endlessly. Our approach is demonstrated by synthesizing the long kungfu motion texture without visual artifacts, together with post-processing including our new developed graphcut-based motion blending and Poisson-based motion smoothing techniques.

关键词： Motion capture Motion texture Character animation Graphcut

FLUORENE-BRIDGED POLYPHENYLQUINOXALINES WITH HIGH SOLUBILITY AND GOOD THERMAL STABILITY:SYNTHESIS AND PROPERTIES

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Chinese Journal of Polymer Science 2010年第6期28卷 971-980页

作者： Cheng Li Zhuo Li jin-gang Liu Hai-xia Yang Shi-yong Yang Laboratory of Advanced Polymer Materials Institute of ChemistryChinese Academy of SciencesBeijing 100190China

A novel fluorene-bridged tetraketone monomer,9,9-bis[(4-benzilyloxy)phenyl]fluorene(FLTK) was synthesized and *** tetraketone was polymerized with various aromatic tetraamines to afford a series of polyphenylquinoxalines(PPQs).The obtained polymers were found to be soluble in common organic solvents such as N-methyl-2-pyrrolidone(NMP),chloroform and *** and tough PPQ films obtained by spin-casting their NMP solutions exhibited tensile strengths higher than 60 *** films also demonstrated good thermal stability up to 500℃in nitrogen and glass transition temperatures higher than 280℃.In addition,the PPQ films exhibited good hydrolytic stability. High surface and volume resistivity retentions were achieved for the films after immersion or boiling in water for 24 h.

关键词： Polyphenylquinoxaline Fluorene Solubility Thermal stability Hydrolytic stability

Synthesis of Large-Pore ECNU-19 Material （12 × 8-R） via Interlayer- Expansion of HUS-2 Lamellar Silicate

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Chinese Journal of Chemistry 2018年第3期36卷 227-232页

作者： Boting Yang jin-gang Jiang Hao Xu Haihong Wu Peng Wu Shanghai Key Laboratory of Green Chemistry and Chemical Processes School of Chemistry and Molecular Engineering East China Normal University North Zhongshan Road 3663 Shanghai 200062 China Department of Chemistry and Biology Beihua University Jiiin Road 15 Jilin Jilin 132013 China

A Yarge-pore ECNU-19 material with unique pore system consisting of 12-ring （12R） pore channels intersected by 8R channels was post-synthesized via interlayer-expansion of HUS-2 lameliar silicate with silylating agent of 1,3-dimethyltetramethoxydisiloxane （DMTMDS）. In consideration of the fact that the HUS-2 precursor possessed a special structure with a malposition of the neighboring layers as well as silicon vacancies on layer surface, a ＂detemplating disassembly - intercalation reassembly - silylation＂ strategy was proposed to realize a successful interlayer-expansion and structural amending. An acid treatment was firstly performed to remove a part of the structure-directing agent molecules, which favored the following intercalation by bulk organic species. The intercalation not only rearranged the relative position of up-down layers but also provided enough interlayer space for the insertion of dimeric silane molecules. Two -OH groups attached to one silicon atom of the silane molecule reacted with two close silanols on the up-surface layer, while the other two -OH groups condensed with two silanols on the down-surface layer, which then connected the two layers via -Si-O-Si- pillars and constructed new 22R pores along o axis and 8R pores along c axis, respectively.

关键词： lamellar silicate HUS-2 interlayer-expansion large-pore material silylation

Class imbalance problem in short-term solar flare prediction

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Research in Astronomy and Astrophysics 2021年第9期21卷 231-236页

作者： Jie Wan Jun-Feng Fu jin-Fu Liu Jia-Kui Shi Cheng-gang jin Huai-Peng Zhang Laboratory for Space Environment and Physical Sciences Harbin Institute of Technology School of Electrical Engineering and Automation Harbin Institute of Technology School of Energy Science and Engineering Harbin Institute of Technology

Using data-driven algorithms to accurately forecast solar flares requires reliable data *** solar flare dataset is composed of many non-flaring samples with a small percentage of flaring *** is called the class imbalance problem in data mining *** prediction model is sensitive to most classes of the original data set during ***,the class imbalance problem for building up the flare prediction model from observational data should be systematically *** at the problem of class imbalance,three strategies are proposed corresponding to the data set,loss function,and training process:TypeⅠresamples the training samples,including oversampling for the minority class,undersampling,or mixed sampling for the majority ***Ⅱusually changes the decision-making boundary,assigning the majority and minority categories of prediction loss to different ***Ⅲassigns different weights to the training samples,the majority categories are assigned smaller weights,and the minority categories are assigned larger weights to improve the training process of the prediction *** main work of this paper compares these imbalance processing methods when building a flare prediction model and tries to find the optimal *** results show that among these strategies,the performance of oversampling and sample weighting is better than other strategies in most parameters,and the generality of resampling and changing the decision boundary is better.

关键词： The Sun Sun:X-rays,gamma rays Sun:sunspots Sun:magnetic fields Sun:flares methods:data analysis

Hybrid windowed networks for on-the-fly Doppler broadening in RMC code

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Nuclear Science and Techniques 2021年第6期32卷 70-82页

作者： Tian-Yi Huang Ze-Guang Li Kan Wang Xiao-Yu Guo jin-gang Liang Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084China Department of Engineering Physics Tsinghua UniversityBeijing 100084China

On-the-fly Doppler broadening of cross sections is important in Monte Carlo simulations,particularly in Monte Carlo neutronics-thermal hydraulics coupling *** such as Target Motion Sampling(TMS)and windowed multipole as well as a method based on regression models have been developed to solve this ***,these methods have limitations such as the need for a cross section in an ACE format at a given temperature or a limited application energy *** this study,a new on-the-fly Doppler broadening method based on a Back Propagation(BP)neural network,called hybrid windowed networks(HWN),is proposed to resolve the resonance energy *** the HWN method,the resolved resonance energy range is divided into windows to guarantee an even distribution of resonance *** networks with specially designed structures and training parameters are trained to evaluate the cross section at a base temperature and the broadening *** HWN method is implemented in the Reactor Monte Carlo(RMC)code,and the microscopic cross sections and macroscopic results are *** results show that the HWN method can reduce the memory requirement for cross-sectional data by approximately 65%;moreover,it can generate keff,power distribution,and energy spectrum results with acceptable accuracy and a limited increase in the calculation *** feasibility and effectiveness of the proposed HWN method are thus demonstrated.

关键词： Monte Carlo method Reactor Monte Carlo(RMC) On-the-fly Doppler broadening BP network

Stand establishment,root development and yield of winter wheat as affected by tillage and straw mulch in the water deficit hilly region of southwestern China

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Journal of Integrative Agriculture 2016年第7期15卷 1480-1489页

作者： LI Chao-su LI jin-gang TANG Yong-lu WU Xiao-li WU Chun HUANG gang ZENG Hui Crop Research Institute Sichuan A cademy of Agricultural SciencesChengdu 610066P.R.China College of Agriculture Sichuan Agricultural UniversityWenjiang 611130P.R.China Agricultural Bureau of Jianyang City Jianyang 621700P.R.China

Good crop stand establishment and root system development are essential for optimum grain yield of dryland wheat （Triti-cum aestivumL.）. At present, little is known about the effect of tilage and straw mulch on the root system of wheat under dryland areas in southwestern China. The aim of this study was to evaluate the effect of three tilage treatments （no-til, NT; rotary til, RT; conventional til, CT） and two crop residue management practices （straw mulch, ML; non-straw mulch, NML） on stand establishment, root growth and grain yield of wheat. NT resulted in lower soil cover thickness for the wheat seed, higher number of uncovered seeds, lower percentage of seedling-less ridges and lower tiler density compared to RT and CT; ML resulted in higher tiler density compared to NML. Straw mulching resulted in more soil water content and root length density （RLD） at most of the growth stages and soil depths. The maximum RLD, root surface area density and root dry matter density were obtained under NT. In the topmost 10 cm soil layer, higher RLD values were found under NT than those under RT and CT. There were no signiifcant differences in the yield or yield components of wheat among the tilage treatments in 2011–2012, but NT resulted in a signiifcant higher yield compared to RT and CT in 2012–2013. Grain yield was signiifcantly higher in ML compared to in NML. A strong relationship was observed between the water-use efifciency and the grain yield. Both NT and ML proved beneifcial for wheat in term of maintaining higher tiler density, better soil water status and root growth, leading to a higher grain yield and enhanced water-use efifciency, especialy in a low rainfal year.

关键词： wheat tilage mulch stand establishment yield Triticum aestivum

Expression Optimization and Characterization of the Catalytic Domain of Human MT3-MMP

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Chemical Research in Chinese Universities 2006年第2期22卷 129-133页

作者： SHI Xiu-juan jin Feng-hai WANG Hui-ling YANG jin-gang WANG Zhi-yong FANG Xue-xun Key Laboratory of Molecular Enzymology and Engineering the Ministry of Education School of Pharmacy College of Life Science Jilin University Changchun 130021 P. R. China

Matrix metalloproteinases（MMPs） are a family of proteases that are required for many biological processes and are also elevated in many pathological conditions. MMP inhibitors （MMPIs） may therefore be useful as therapeutic agents in treating a number of diseases including cancer, cardiovascular diseases and arthritis. Attempts have been made to develop MMPIs. Recombinant MMPs have been used to screening MMPs in vitro assays. In this work, we report the expression of MMP-16 in E. coli and the characterization of the recombinant MMP-16 with a commonly used MMP substrate DQ-gelatin.

关键词： Matrix metalloproteinase(MMP) Protein expression Catalytic domain MMP-16

Are the Economic Consequences of Climate Change Really “Pro-Poor”?

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China Finance and Economic Review 2021年第2期10卷 3-21页

作者： gang jin Kunrong Shen Yuting Sun School of Economics of Nanjing University and Ph.D.in Economics School of Economics&Management of Southeast University China

In order to comprehensively study the influence of climate change on economic growth and energy conservation&emission reduction,this paper fi rst uses the non-radial directional distance function(NDDF)to calculate the city-level green economic efficiency in China during *** causal effect of daily temperature changes on green economic efficiency is then identifi ed to evaluate the economic consequences of climate *** fi nds that r elative to the 6~12℃temperature benchmark,any decrease or increase in temperature will pose negative influence on green economic efficiency;moreover,such effects are only observed in developed cities,but not signifi cant in less-developed *** refl ects that the economic consequences of climate change are“robbing the rich”to some extents,which differs widely from the“pro-poor”conclusion in the majority of literature *** to the robustness test and with possible competitive explanations excluded,this finding still *** mechanism test reveals that temperature rise brings about economic consequences that“rob the rich”by affecting labor productivity,efficiency of energy conservation&emission reduction and execution of environmental regulations by local *** study brings a different perspective for understanding the economic consequences of climate change and offers empirical basis for identifying responsibilities of local government in climate governance.

关键词： climate change green economic efficiency adaptive behavior energy conservation&emission reduction