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Quantum McKay Correspondence for Disc Invariants of Toric Calabi–Yau 3-orbifolds

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Acta Mathematica Sinica,English Series 2015年第1期31卷 29-34页

作者： hua-zhong ke Jian ZHOU Department of Mathematical Sciences Tsinghua University

We announce a result on quantum McKay correspondence for disc invariants of outer legs in toric Calabi-Yau 3-orbifolds, and illustrate our method in a special example [C^3/Z5（1, 1, 3）].

关键词： Quantum McKay correspondence disc invariants open mirror symmetry

On the Drinfeld-Sokolov hierarchy of type E_(6)^((1))and its topological solution

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Science China Mathematics 2021年第6期64卷 1245-1262页

作者： Weiqiang He hua-zhong ke Chao-zhong Wu School of Mathematics Sun Yat-sen UniversityGuangzhou 510275China

In this paper we report some explicit evolutionary PDEs of the Drinfeld-Sokolov hierarchy of type E_(6)^((1)),and show how the unknown functions in these PDEs are related to the tau ***,for this hierarchy we compute its topological solution of formal series up to a certain degree,whose coefficients of monomials give the Fan-Jarvis-Ruan-Witten invariants for the E_(6) simple *** on such results we also derive several explicit evolutionary PDEs and some low-degree terms of the topological solution for the Drinfeld-Sokolov hierarchy of type F_(4)^((1)).

关键词： Drinfeld-Sokolov hierarchy tau function topological solution

On the Quantum Cohomology of Blow-ups of Four-dimensional Quadrics

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Acta Mathematica Sinica,English Series 2024年第1期40卷 313-328页

作者： Jian Xun HU hua zhong ke Chang Zheng LI Lei SONG School of Mathematics Sun Yat-sen UniversityGuangzhou 510275P.R.China

We propose a conjecture relevant to Galkin’s lower bound conjecture,and verify it for the blow-ups of a four-dimensional quadric at a point or along a projective *** also show that Conjecture O holds in these two cases.

关键词： Quantum cohomology blow-up quadric hypersurface

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三相SPWM逆变电源故障检测与诊断的仿真研究

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系统仿真学报 2004年第7期16卷 1512-1515页

作者：吴小华史忠科西北工业大学自动化学院西安710072

该文建立了三相SPWM逆变电源的非线性的MATLAB仿真模型,通过仿真试验获得逆变电源发生开关器件断路时的数据矩阵,构造系统神经网络的学习样本,并以此训练神经网络,确定了用于三相SPWM逆变电源故障诊断的神经网络结构和参数。仿真验证试... 详细信息

该文建立了三相SPWM逆变电源的非线性的MATLAB仿真模型,通过仿真试验获得逆变电源发生开关器件断路时的数据矩阵,构造系统神经网络的学习样本,并以此训练神经网络,确定了用于三相SPWM逆变电源故障诊断的神经网络结构和参数。仿真验证试验结果表明所设计的基于人工神经网络的电力电子逆变电路的故障诊断系统是可行的。

关键词： SPWM逆变电源仿真故障诊断神经网络

Second Intron of Mouse Nestin Gene Directs its Expression in Pluripotent Embryonic Carcinoma Cells through POU Factor Binding Site

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Acta Biochimica et Biophysica Sinica 2006年第3期38卷 207-212页

作者： Zhi-Gang JIN Li LIU hua zhong ke-Jing ZHANG Yong-Feng CHEN Wei BIAN Le-Ping CHENG Nai-He JING* Laboratory of Stem Cell Biology,Laboratory of Molecular Cell Biology,Institute of Biochemistry and Cell Biology,Shanghai Institutes for Biological Sciences,Chinese Academy of Sciences,Shanghai 200031,China LaboratoryofStemCellBiology LaboratoryofMolecularCellBiologyInstituteofBiochemistryandCellBiologyShanghaiInstitutesforBiologicalSciencesChineseAcademyofSciencesShanghai200031China

Nestin,an intermediate filament protein,is expressed in the neural stem cells of the developingcentral nervous *** tissue-specific expression is driven by the neural stem cell-specific enhancer inthe second intron of the nestin *** this study,we showed that the mouse nestin gene was expressed inpluripotent embryonic carcinoma (EC) P19 and F9 cells,not in the differentiated cell *** cell type-specific expression was conferred by the enhancer in the second *** of the conserved POUfactor-binding site in the enhancer abolished the reporter gene expression in EC ***4,a Class V POUfactor,was found to be coexpressed with nestin in EC *** mobility-shift assays and supershiftassays showed that a unique protein-DNA complex was formed specifically with nuclear extracts of ECcells,and Oct4 protein was ***,these results suggest the functional relevance between theconserved POU factor-binding site and the expression of the nestin gene in pluripotent EC cells.

关键词： nestin embryonic carcinoma cells enhancer POU factor

Combined 99Tcm-ECD SPECT and nuropsychological studies identify mild cognitive impairment from Alzheimers disease

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Combined 99Tcm-ECD SPECT and nuropsychological studies ident...

中华医学会第九次全国核医学学术会议

作者： MU Da(310016 Department of Nuclear Medicine,Sir Run Run Shaw Hospital,School of Medicine,Zhejiang Univerbity,Hangzhou,China) CHEN Wei WEI Li-li CHEN Dong-fang ZHANG Bu-chen huaNG hua-cheng huaNG zhong-ke SHI Guo-hua LOU Cen

Objective This study was to evaluate whether Tc-ECD SPECT combined with nuropsychological memory scores could identify preclinical AD in patients with mild cognitive impairment (MCI).Methods Nineteen outpatients refer...

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来源： cnki会议评论

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cnki会议

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基于灰色马尔可夫模型的煤层气抽采量预测

工业工程与管理 2012年第4期17卷 108-113,120页

作者：王金凤余华杰冯立杰崔庆安钟华珂郑州大学管理工程研究所河南郑州450001 河南省煤层气开发利用有限公司河南郑州450016

煤层气抽采量的准确预测,对煤层气开发利用工作的科学决策和发展规划具有重要意义。通过灰色系统理论与马尔可夫理论的结合,建立灰色马尔可夫模型对煤层气抽采量进行预测分析。首先建立煤层气抽采量的GM(1,1)预测模型,确定其变动趋势和... 详细信息

煤层气抽采量的准确预测,对煤层气开发利用工作的科学决策和发展规划具有重要意义。通过灰色系统理论与马尔可夫理论的结合,建立灰色马尔可夫模型对煤层气抽采量进行预测分析。首先建立煤层气抽采量的GM(1,1)预测模型,确定其变动趋势和初始预测值,然后应用马尔可夫理论对初始预测结果进行修正,最后通过实例计算验证了灰色马尔可夫模型的适用性。结果表明,灰色马尔可夫模型的预测精度明显高于传统GM(1,1),更适用于随机波动性较大的序列预测问题,因此将灰色马尔可夫模型用于煤层气抽采量预测是合理和可行的。

关键词：煤层气抽采量预测 GM(1,1)模型灰色马尔可夫模型

Potassium ions and cyano group modified g-C3N4 for effective generation of H2O2 through two-electron oxygen reduction

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Science China Chemistry 2025年第1期 192-200页

作者： Dongying Wang Shulan Pu Yongmin Chen ke Lei Yujie Duan Linjiao Mao Xuhui Zeng Xi Luo Yuntao Zhang Yuqin Dong Jin zhong Zhang Yan Sun School of Mechanical Engineering Chengdu University Department of Chemistry and Biochemistry University of California

Potassium ions （K+） doped graphitic carbon nitride （g-C3N4） was prepared by a thermal etching method using potassium hydroxide （KOH） as an ion *** transform infrared spectroscopy （FTIR） and X-ray photoelectron spectroscopy （XPS）results showed that the generation of the cyano group was detected while introducing K+.Under simulated sunlight irradiation,the sample with a K+doping amount of 10%showed the highest hydrogen peroxide （H2O2） generation rate of2,140.2μmol *** apparent quantum yield （AQY） at 400 nm and the solar-to-chemical conversion （SCC） are 4.35%and1.23%,respectively.K+acted as a bridge between g-C3N4layers,which enhanced charge transfer ***,the cyano group enhanced the adsorption capacity of protons （H+） and promoted the yield of *** catalyst exhibited excellent photocatalytic stability based on four-cycle *** addition,a mechanism study showed that superoxide radicals （·O2-）were the most important active species in the reaction *** production of H2O2was achieved through consecutive single-electron *** study deepens the understanding of the oxygen reduction reaction process and opens up a new venue for improving H2O2generation.

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Actively tunable electromagnetically induced transparency in hybrid Dirac-VO2 metamaterials

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Optoelectronics Letters 2025年第1期21卷 13-20页

作者： DI ke XIE Meng XIA huarong CHENG Anyu LIU Yu DU Jiajia Department of Optoelectronic Engineering Chongqing University of Post and Telecommunications Chongqing key Laboratory of Autonomous Navigation and Microsystem Chongqing University of Posts and Telecommunications Department of Automation Chongqing University of Post and Telecommunications

In this paper, we present a metamaterial structure of Dirac and vanadium dioxide（VO2） and investigate its optical properties using the finite-difference time-domain（FDTD） technique. Using the phase transition feature of VO2, the design can realize active tuning of the plasmon induced transparency（PIT） effect at terahertz frequency, thereby converting from a single PIT to a double-PIT. When VO2is in the insulating state, the structure is symmetric to obtain a single-band PIT effect. When VO2is in the metallic state, the structure turns asymmetric to realize a dual-band PIT effect. This design provides a reference direction for the design of actively tunable metamaterials. Additionally, it is discovered that the transparent window's resonant frequency and the Fermi level in this structure have a somewhat linear relationship. In addition, the structure achieves superior refractive index sensitivity in the terahertz band, surpassing 1 THz/RIU. Consequently, the design exhibits encouraging potential for application in refractive index sensors and optical switches.

关键词： Transparency