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指向高质量课堂的听评课量表设计及其关键问题

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教学与管理 2025年第1期 24-28页

作者：户艳茹方妍清华大学教育研究院北京100084 清华大学附属中学北京100084

在建设高质量课堂的时代背景下,重新设计课堂听评课框架与维度,有助于倒逼教师专业成长,反促课堂提质增效。在深刻反思现有听评课量表存在不足、尤其是缺乏科学量化标准的前提下,重新设计的旨在提升课堂质量的听评课量表主要包括2个观... 详细信息

在建设高质量课堂的时代背景下,重新设计课堂听评课框架与维度,有助于倒逼教师专业成长,反促课堂提质增效。在深刻反思现有听评课量表存在不足、尤其是缺乏科学量化标准的前提下,重新设计的旨在提升课堂质量的听评课量表主要包括2个观察维度、6个观察要素、13个观察指标和26个观察点。在教学实践中应用这一听评课量表,需要注意凸显学生的主体性、全面性与个性化,构建民主平等的课堂生命共同体,展现时代风格与学校特色,形成良性教研文化和沟通合作机制。

关键词：高质量课堂听评课量表教研制度

Feature Selection, Deep Neural Network and Trend Prediction

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Journal of Shanghai Jiaotong university(Science) 2018年第2期23卷 297-307页

作者： fang yan School of Statistics and Management Shanghai University of Finance and Economics Shanghai 200433 Chin School of Finance Shanghai University of International Business and Economics Shanghai 201620 China

The literature generally agrees that longer-horizon(over a month) predictions make more sense than short-horizon ones. However, it's an especially challenging task due to the lack of data(in unit of long horizon)and economic data have a low S/N ratio. We hypothesize that the stock trend is largely dictated by driving factors which are filtered by psychological factors and work on behavioral factors: representative indicators from these three aspects would be adequate in trend prediction. We then extend the Stepwise Regression Analysis(SRA)algorithm to constrained SRA(c SRA) to carry out a further feature selection and lag optimization. During modeling stage, we introduce the Deep Neural Network(DNN) model in stock prediction under the suspicion that economic interactions are too complex for shallow networks to capture. Our experiments indeed show that deep structures generally perform better than shallow ones. Instead of comparing to a kitchen sink model, where over-fitting can easily happen with a shortage of data, we turn around and use a model ensemble approach which indirectly demonstrates our proposed method is adequate.

关键词： feature selection trend prediction constrained Stepwise Regression Analysis(c SRA) Deep Neural Network(DNN)

Numerical Simulation of the Dynamic Behaviors of a Gas Tungsten Welding Arc for Joining Magnesium Alloy AZ61A

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Acta Metallurgica Sinica(English Letters) 2013年第5期26卷 588-596页

作者： Zhenmin WANG fang yan Pengcheng ZHAO School of Mechanical & Automotive Engineering South China University of Technology College of Electromechanical Engineering Qingdao University of Science and Technology

Based on the Magneto-Hydro-Dynamic（MHD） theory, a united three-dimensional（3D） transient numerical model is developed to investigate the dynamic behaviors of arc plasma for a magnesium alloy AZ61A gas tungsten arc welding（GTAW） arc. The arc, electrode and workpiece are integrated into one calculation domain to avoid both presumed distribution of the current density at the electrode tip and the assumption of constant conditions of interface between welding arc and workpiece. The distributions of electric potential, current density, magnetic flux density, electromagnetic force, velocity, temperature, and pressure of the arc plasma in the 3D space are analyzed by using the numerical model. Results indicate that the maximum gradient of the electric potential in the whole arc space exists around the electrode tip, where the electric current density, electromagnetic force, and temperature are also the maximum. However, maximum pressure is found at the velocity stagnation, which is above the *** between predicted temperature and measured one in arc region shows a good agreement.

关键词： GTAW Arc MHD theory Dynamic behavior Numerical simulation

Crystallization of self-propelled particles on a spherical substrate

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Applied Mathematics and Mechanics(English Edition) 2019年第10期40卷 1387-1398页

作者： yan fang Chen WANG Hongyuan JIANG CAS Key Laboratory of Mechanical Behavior and Design of Materials Hefei National Laboratory for Physical Science at the Microscale Department of Modern Mechanics University of Science and Technology of China

In this paper, we investigate the self-propelled particles confined on a spherical substrate and explore the structural and dynamic properties of self-propelled particles by controlling the packing fraction and activity. We find that these self-propelled particles freeze into the crystal with the increase in the packing fraction. We observe the pattern evolution of inevitable topological defects due to the geometric constraints of the spherical substrate. During the process of freezing, there is a transition from twelve isolated grain boundaries to the uniform distribution of defects with the increase in the self-propelled velocity. Finally, we establish a phase diagram of the freezing process. These results may deepen our understanding of active particles in complex and crowded environments.

关键词： self-prop elled particle freezing process geometric constraint defect

A Characterization of Generalized Derivations of JSL Algebras

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Acta Mathematica Sinica,English Series 2017年第4期33卷 495-500页

作者： Lin CHEN fang yan LU Department of Mathematics Soochow University Department of Mathematics Anshun University

Let AlgL be a J-subspace lattice algebra on a Banach space X and M be an operator in AlgL. We prove that if δ : AlgL → B(X) is a linear mapping satisfying δ(AB) = δ(A)B + Aδ(B)for all A, B ∈ AlgL with AMB = 0, then δ is a generalized derivation. This result can be applied to atomic Boolean subspace lattice algebras and pentagon subspace lattice algebras.

关键词： Generalized derivation derivation derivable mapping

Structure of aqueous sodium sulfate solutions derived from X-ray diffraction

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Chinese Science Bulletin 2009年第12期54卷 2022-2027页

作者： XU JiXiang fang yan fang ChunHui Key Laboratory of Salt Lake Resources and Chemistry Qinghai Institute of Salt Lakes Chinese Academy of Sciences Xining 810008 China Graduate University of Chinese Academy of Science Beijing 100049 China

A rapid liquid X-ray diffractometer was used to study the time-averaged and space-averaged structure of aqueous sodium sulfate solutions at 298 and 323 K. Difference radial distribution functions of the solutions were obtained from accurate diffraction data. The interaction distances of Na+-OH2 and S-H2O in solutions were found to be 0.235 and 0.385 nm, respectively, after deconvolution of superposition peaks by Gaussian multi-peak fitting program. The characteristic distance of the NaSO4-contact ion pairs in higher concentration solutions was determined to be 0.345 nm, suggesting that the Na+ ions coordinated with SO42- ions in the mono-dentate form. Effects of concentration and temperature on the hydration structure of the solutions were discussed in the present paper. With a decrease in concentration, the contributions of the H2O to the diffraction pattern increase, the average coordination number of the Na+ ions hardly changes, while the hydration number of SO42-ions increases slightly. The formation of NaSO4-contact ion pairs becomes easier at higher temperature. The structure of hydrogen bond in dilute solutions is broken to a considerable extent with rising temperature, and the peak at 0.290 nm splits into two peaks at 0.275 and 0.305 nm, respectively.

关键词： X射线衍射仪硫酸钠结构水接触离子对径向分布函数中高浓度温度升高作用距离

Scattering Versus Blowup Beyond the Mass-Energy Threshold for the Davey–Stewartson Equation in R^(3)

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Acta Mathematica Sinica,English Series 2021年第9期37卷 1415-1436页

作者： yan fang GAO Zhi Yong WANG School of Mathematics and Statistics&Fujian Key Laboratory of Mathematical Analysis and Applications Fujian Normal UniversityFuzhou 350117P.R.China

We study the Cauchy problem for the Davey–Stewartson equation i?tu+Δu+|u|^(2) u+E1(|u|^(2))u=0,(t,x)∈R×R^(3).The dichotomy between scattering and finite time blow-up shall be proved for initial data with finite va... 详细信息

关键词： Davey–Stewartson equation scattering blow-up finite variance

Semiconducting M_(2)X(M=Cu,Ag,Au;X=S,Se,Te)monolayers:A broad range of band gaps and high carrier mobilities

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Nano Research 2021年第8期14卷 2826-2830页

作者： Lei Gao yan-fang Zhang Shixuan Du Institute of Physics&University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing 100190China Faculty of Science Kunming University of Science and TechnologyKunming 650000China CAS Key Laboratory of Vacuum Physics Beijing 100049China

Two-dimensional semiconductors(2DSCs)with appropriate band gaps and high mobilities are highly desired for future-generation electronic and optoelectronic ***,using first-principles calculations,we report a novel class of 2DSCs,group-11-chalcogenide monolayers(M_(2)X,M=Cu,Ag,Au;X=S,Se,Te),featuring with a broad range of energy band gaps and high carrier *** energy band gaps extend from 0.49 to 3.76 eV at a hybrid density functional level,covering from ultraviolet-A,visible light to near-infrared region,which are crucial for broadband ***,the calculated room-temperature carrier mobilities of the M_(2)X monolayers are as high as thousands of cm^(2)·V^(-1)·s^(-1).Particularly,the carrier mobilities ofε-Au_(2)Se and e-Au2Te are up to 104 cm^(2)·V^(-1)·s^(-1),which is very attracitive for electronic *** from the broad range of energy band gaps and superior carrier mobilities,the group-11-chalcogenide M_(2)X monolayers are promising candidates for future-generation nanoelectronics and optoelectronics.

关键词： two-dimensional semiconductors group-11-chalcogenides electronic properties first-principles calculations

Synthesis and in vitro-Anti-hepatitis B Virus Activities of Several Ethyl 5-Hydroxy-1H-indole-3-carboxylates

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Chemical Research in Chinese Universities 2006年第5期22卷 577-583页

作者： ZHAO Chun-shen ZHAO yan-fang CHAI Hui-fang GONG Ping Liaoning Province Key Laboratory of Innovative Medicine Research and Design Shenyang Pharmaceutical University Shenyang 110016 P. R. China

A series of ethyl 5-hydroxyindole-3-earboxylates 6a-10r was designed and synthesized. The structures of all the compounds were confirmed by IR, ^1H NMR, and MS and their anti-hepatitis B virus （HBV） activities were evaluated in 2.2.15 cells. Among them, compound 7g { ethyl 5-hydroxy-2- [ （ 3-methoxyphenylsulfinyl ） methyl ] -1-methyl-4- [ （4-methylpiperazin-1-yl） methyl ]-1H-indole-3-carboxylate} displays a significant anti-HBV activity, which is more potent than the positive control lamivudine.

关键词： Ethyl 5-hydroxy-1H-indole-3-carboxylates Synthesis Anti-hepatitis B virus activity