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Corneal endothelial cell density and morphology and central corneal thickness in Guangxi Maonan and Han adolescent students of China

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International Journal of Ophthalmology(English edition) 2015年第3期8卷 608-611页

作者： Hao Liang Hui-Yi Zuo Jin-Mao Chen Jie Cai yu-zhua qin yu-Ping Huang Ying-Ying Chen Dong-Yong Tang Shao-Jian Tan Department of Ophthalmology the First Affiliated Hospital of Guangxi Medical University People's Hospital of Huanjiang Maonan Autonomous County

AIM: To investigate the corneal endothelial cell density and morphology and central corneal thickness in the Guangxi Maonan and Han adolescent students of ***: Noncontact specular microscope(Topcon SP3000 P, Tokyo, Japan) was performed in 133 adolescent students of Maonan nationality(M:F 54:79)and 105 adolescent students of Han nationality(M:F 50:55),5 to 20 y of age, who were randomly selected from 3schools in Huanjiang Maonan Autonomous County of Guangxi zhuang Autonomous Region of *** studied included endothelial cell density,mean cell area, coefficient of variation in cell size,percentage hexagonality and central corneal thickness. RESULTS: Endothelial cell density, mean cell area,coefficient of variation in cell size, percentage hexagonality and central corneal thickness in the study population were(2969.50 ±253.93) cells/mm2,(339.23 ±29.44) μm2,(29.96 ±4.07) %,(64.58 ±9.41) % and(523.71 ±32.82) μm in Maonan and(2998.26 ±262.65) cells/mm2,(336.11±30.07) μm2,(29.89±5.03) %,(64.91±11.64) % and(524.39 ±33.15) μm in Han, respectively. No significant differences were observed in endothelial cell density,mean cell area, coefficient of variation in cell size,percentage hexagonality and central corneal thickness between Maonan and Han(P =0.615, 0.659, 0.528, 0.551,0.999). In Maonan and Han, we found age was negatively correlated with endothelial cell density and percentagehexagonality and positively correlated with mean cell area and coefficient of variation in cell size. Negative correlation was also found between central corneal thickness and age in Han, whereas no correlation was found in Maonan. CONCLUSION: There were no differences between Maonan and Han in corneal endothelial cell density and morphology and central corneal thickness. In these two nationalities, there were statistically significant decrease in endothelial cell density and percentage hexagonality with increasing age and statistically significant increase in cell area and coef

关键词： endothelial cell density morphology central corneal thickness Maonan

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HMFI分子筛Bronsted酸性位点与碱性分子的作用机制

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原子与分子物理学报 2025年第4期42卷 1-7页

作者：郑健秦康秦玉才宋丽娟中石化石油化工科学研究院有限公司北京100083 辽宁石油化工大学辽宁省石油化工催化科学与技术重点实验室抚顺113001

采用密度泛函理论(DFT)方法,以单铝、双铝和三铝酸性位点HMFI分子筛为模型分子筛,计算去质子化能考察HMFI分子筛的本征酸性,以NH_(3)分子作为模型分子,计算NH_(3)分子在HMFI分子筛中的吸附能与去质子化能进行关联性分析,并进一步考察NH_... 详细信息

采用密度泛函理论(DFT)方法,以单铝、双铝和三铝酸性位点HMFI分子筛为模型分子筛,计算去质子化能考察HMFI分子筛的本征酸性,以NH_(3)分子作为模型分子,计算NH_(3)分子在HMFI分子筛中的吸附能与去质子化能进行关联性分析,并进一步考察NH_(3)分子与HMFI分子筛的作用机制.研究表明分子筛Bronsted酸(简称B酸)强度与B酸数量没有强相关性,在考虑B酸位数量的同时须考虑B酸位的分布.酸性位点数量和分布的差异均可以调控NH_(3)分子的吸附构象,并且可以通过调节HMFI分子筛孔道对分子施加相互作用的模式,解析分子的结构和电子性质,精准调控分子的进一步转化.此项工作可以为未来高效多孔材料有效物种活性位的构建提供新思路.

关键词：密度泛函理论 HMFI分子筛 Bronsted酸性质吸附性能

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基于4G技术的工程结构无线振动测试系统节点设计

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太原学院学报（自然科学版） 2025年第1期43卷 38-46页

作者：秦乐余沛信阳学院土木工程学院河南信阳464000

结构振动测试是大型土木工程结构健康监测的有效保障,传统振动测试存在布线困难、低频率信号拾取困难、通信速率底、易受到测试现场条件限制等问题。以4G技术为研究对象,提出了一种基于4G技术的工程结构无线振动测试系统节点设计方案,... 详细信息

结构振动测试是大型土木工程结构健康监测的有效保障,传统振动测试存在布线困难、低频率信号拾取困难、通信速率底、易受到测试现场条件限制等问题。以4G技术为研究对象,提出了一种基于4G技术的工程结构无线振动测试系统节点设计方案,通过节点工作原理介绍及各个模块的功能特性分析,研究了标准振动台性能对比测试和基于有线及无线的结构振动对比试验。结果表明:节点传感器的线性度误差为0.29%,且在短距离以及超远距离测试条件下,试验结构的各阶频率测试结果均与有线加速度传感器的测试结果一致,表明节点在测试精度和数据高速率传输等方面具有较大优势,解决了中远及超远距离中工程数据传输问题,具有一定的工程实用性,在土木工程健康监测和工程强震观测领域具有广泛的应用前景。

关键词： 4G通信技术无线振动测试节点灵敏度脉动自由衰减

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A real-time multi-head mixed attention mechanism-based prediction method for tunnel boring machine disc cutter wear

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Science China Technological Sciences 2025年第1期 290-311页

作者： Haodi WANG Chengjin qin Honggan yu Zhinan ZHANG Guoqiang HUANG Zhengyang LIU Chengliang LIU State Key Laboratory of Mechanical System and Vibration School of Mechanical EngineeringShanghai Jiao Tong University

In the process of hard rock tunnel excavation, workers often need to enter the tunnel boring machine(TBM)cutterhead at regular intervals to measure cutter wear. However, this method is time-consuming and labor-intensive. Existing cutter prediction models primarily rely on geological parameters to predict overall cutter wear before construction, making it challenging to monitor real-time wear at different locations of the cutter and obtain accurate geological parameters. To address these challenges, this paper proposes a multi-head mixed attention mechanism-based method for real-time wear prediction of TBM disc cutter. First, a method of cutter wear normalization to eliminate measurement noise is explored. Then, considering the complex correlation of TBM operating parameters in feature and time dimensions, a new multi-head mixed attention mechanism model is designed to establish the dependency between different features and different moments, to better establish the mapping model between operating parameters and cutter wear. Finally, the current cutter wear state can be calculated by accumulating the wear amount of all previous small excavation sections. The effectiveness of the method is verified by using field data from the Mumbai tunnel. The results demonstrate that the method is capable of real-time prediction of front cutter and edge cutter wear on the test set, achieving an average accuracy rate of 95.75%. Moreover, the method can update the cutter wear status after every meter of excavation, which has good real-time performance. In addition, the average accuracy of cutter wear prediction of the proposed method is 11.75%, 10.375%, 3.875%, 3.625%, 1.375%, 3.125%, 2.25%, and 0.75%higher than that of LSTM, CNN, LSTM-CNN, CACNN, SACNN, MMADNN, MTACNN, and MFACNN. In summary, this approach offers an accurate prediction of cutter wear state while reducing inspection time and costs and has high application value.

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Fast-growing procedure for perovskite films in planar heterojunction perovskite solar cells

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Chinese Chemical Letters 2015年第12期26卷 1518-1521页

作者： Tang-Hao Liu Ke Chen qin Hu Jiang Wu De-Ying Luo Shuang Jia Rui zhua Qi-Huang Gong State Key Laboratory for Artificial Microstructure and Mesoscopic Physics School of Physics Peking University International Center for Quantum Materials School of Physics Peking University Collaborative Innovation Center of Quantum Matter

A fast-growing procedure（FGP） to fabricate perovskite films with large grain sizes is described in this article. In the FGP method, the perovskite precursor solution is coated onto the substrates at a temperature of 240 8C. The solvent in the precursor solution evaporates quickly in about 2 s, resulting in the rapid formation of a perovskite film without further annealing process. Millimeter-scale perovskite grain clusters are obtained in the film. Based on such perovskite films, fabricated planar heterojunction perovskite solar cells give a power conversion efficiency（PCE） above 8%.

关键词： perovskite planar annealing coated fabricate sizes micrograph quickly evaporation PEDOT

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Learning in games:a systematic review

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Science China(Information Sciences) 2024年第7期67卷 133-159页

作者： Rong-Jun qin Yang yu National Key Laboratory for Novel Software Technology Nanjing University Polixir Technologies

Game theory studies the mathematical models for self-interested individuals. Nash equilibrium is arguably the most central solution in game theory. While finding the Nash equilibrium in general is known as polynomial parity arguments on directed graphs(PPAD)-complete, learning in games provides an alternative to approximate Nash equilibrium, which iteratively updates the player's strategy through interactions with other players. Rules and models have been developed for learning in games, such as fictitious play and no-regret learning. Particularly, with recent advances in online learning and deep reinforcement learning,techniques from these fields greatly boost the breakthroughs in learning in games from theory to *** a result, we have witnessed many superhuman game AI systems. The techniques used in these systems evolve from conventional search and learning to purely reinforcement learning(RL)-style learning methods,gradually getting rid of the domain knowledge. In this article, we systematically review the above techniques,discuss the trend of basic learning rules towards a unified framework, and recap applications in large ***, we discuss some future directions and make the prospect of future game AI systems. We hope this article will give some insights into designing novel approaches.

关键词： non-cooperative games learning in games no-regret learning reinforcement learning superhuman AI

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Small signal stability region of power systems with DFIG in injection space

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Journal of Modern Power Systems and Clean Energy 2013年第2期1卷 127-133页

作者： Chao qin Yixin yu Key Laboratory of Smart Grid Tianjin UniversityTianjin 300072China

The modal analysis method is utilized to study the influence of doubly-fed induction generator(DFIG)on electromechanical *** this basis,the small signal stability region(SSSR)of power systems with DFIG in injection space is evaluated and the corresponding relationship between SSSR boundary and electromechanical oscillations is *** effects of the locations of DFIG on SSSR are *** is found that the boundary of SSSR consists of several smooth surfaces,which can be approximated with hyper-planes in engineering *** the integration of DFIG,SSSR becomes smaller,thus indicating the deterioration of the small signal stability of the *** 11-bus system with four generators is used to illustrate the proposed method.

关键词： Doubly-fed induction generator(DFIG) Modal analysis Electromechanical oscillation Small signal stability region(SSSR)

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The good and evil of complement activation in HIV-1 infection

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Cellular & Molecular Immunology 2010年第5期7卷 334-340页

作者： Qigui yu Richard yu Xuebin qin Department of Microbiology and Immunology University School of Medicine635 Barnhill DriveIndianapolisINUSA Harvard Medical School Laboratory for Translational ResearchCambridgeMAUSA

The complement system,a key component of innate immunity,is a first-line defender against foreign pathogens such as *** role of the complement system in HIV-1 pathogenesis appears to be *** the complement system plays critical roles in clearing and neutralizing HIV-1 virions,it also represents a critical factor for the spread and maintenance of the virus in the infected *** addition,complement regulators such as human CD59 present in the envelope of HIV-1 prevent complement-mediated lysis of *** novel approaches are proposed to combat HIV-1 infection through the enhancement of antibody-dependent complement activity against *** this paper,we will review these diverse roles of complement in HIV-1 infection.

关键词： antibody complement HIV-1 human CD59

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Numerical investigation of flow separation behavior in an over-expanded annular conical aerospike nozzle

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Chinese Journal of Aeronautics 2015年第4期28卷 983-1002页

作者： He Miaosheng qin Lizi Liu yu School of Astronautics Beihang University

A three-part numerical investigation has been conducted in order to identify the flow separation behavior––the progression of the shock structure, the flow separation pattern with an increase in the nozzle pressure ratio（NPR）, the prediction of the separation data on the nozzle wall,and the influence of the gas density effect on the flow separation behavior are *** computational results reveal that the annular conical aerospike nozzle is dominated by shock/shock and shock/boundary layer interactions at all calculated NPRs, and the shock physics and associated flow separation behavior are quite *** abnormal flow separation behavior as well as a transition process from no flow separation at highly over-expanded conditions to a restricted shock separation and finally to a free shock separation even at the deign condition can be *** complex shock physics has further influence on the separation data on both the spike and cowl walls, and separation criteria suggested by literatures developed from separation data in conical or bell-type rocket nozzles fail at the prediction of flow separation behavior in the present asymmetric supersonic *** of flow separation with the gas density is distinct for highly overexpanded *** the gas density or reducing mass flow results in a smaller adverse pressure gradient across the separation shock or a weaker shock system, and this is strongly coupled with the flow separation *** computational results agree well with the experimental data in both shock physics and static wall pressure distribution at the specific NPRs, indicating that the computational methodology here is advisable to accurately predict the flow physics.

关键词： Aerodynamics Aerospike nozzle Flow simulation Flow separation Gas density effect Over-expanded flow Reynolds-averaged Navier-Stokes (RANS)

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Effective method for tracking multiple objects in real-time visual surveillance systems

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Journal of Systems Engineering and Electronics 2009年第6期20卷 1167-1178页

作者： Wang Yaonan Wan qin yu Hongshan Coll. of Electrical and Information Engineering Hunan Univ. Changsha 410082 P. R. China

An object model-based tracking method is useful for tracking multiple objects, but the main difficulties are modeling objects reliably and tracking objects via models in successive frames. An effective tracking method using the object models is proposed to track multiple objects in a real-time visual surveillance system. Firstly, for detecting objects, an adaptive kernel density estimation method is utilized, which uses an adaptive bandwidth and features combining colour and gradient. Secondly, some models of objects are built for describing motion, shape and colour features. Then, a matching matrix is formed to analyze tracking situations. If objects are tracked under occlusions, the optimal ＂visual＂ object is found to represent the occluded object, and the posterior probability of pixel is used to determine which pixel is utilized for updating object models. Extensive experiments show that this method improves the accuracy and validity of tracking objects even under occlusions and is used in real-time visual surveillance systems.

关键词： visual surveillance multiple object tracking object model matching matrix.

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