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Impact of Assimilating Radiances with the WRFDA ETKF/3DVAR Hybrid System on Prediction of Two Typhoons in 2012

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Journal of Meteorological Research 2015年第1期29卷 28-40页

作者：许冬梅黄向宇王洪利 Arthur P.MIZZI 闵锦忠 Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science & Technology National Center for Atmospheric Research BoulderCO 80302USA Global Systems Division Earth System Research LaboratoryNOAABoulderCO 80302USA

The impacts of AMSU-A and IASI（Infrared Atmospheric Sounding Interferometer） radiances assimilation on the prediction of typhoons Vicente and Saola（2012） are studied by using the ensemble transform Kalman filter/three-dimensional variational（ETKF/3DVAR） Hybrid system for the Weather Research and Forecasting（WRF） model. The experiment without assimilating radiance data in 3DVAR is compared with two experiments using the 3DVAR and ETKF/3DVAR hybrid systems to assimilate AMSU-A radiance,respectively. The results show that AMSU-A radiance data have slight positive impacts on track forecasts of the 3DVAR system. When the ETKF/3DVAR hybrid system is employed, typhoon track forecast skills are greatly improved. For 36-h forecasts, the hybrid system has a lower root-mean-square error for wind and temperature at most levels, and specific humidity at low levels, compared to 3DVAR. It is also found that, on average, the use of the IASI radiance data along with AMSU-A radiance data in the hybrid system further increases the track, wind, and specific humidity forecast accuracy compared to the experiment without IASI radiance assimilation.

关键词： hybrid system ETKF ensemble spread radiance data typhoon tracks

Single-Crystal Seeds Inducing the Crystallization of High-performance α-FAPbI3 for Efficient Perovskite Solar Cells

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Single-Crystal Seeds Inducing the Crystallization of High-pe...

第十届新型太阳能材料科学与技术学术研讨会

作者： Jun He Junyan xiang hongli Liu Fei Zhang xianggao Li Shirong Wang Tianjin University School of Chemical Engineering and Technology Collaborative Innovation Center of Chemical Science and Engineering(Tianjin)

α-phase formamidine lead iodine(α-FAPbI) as the competitive candidates to pursue highperformance perovskite solar cells(PSCs) suffers the weakness of random nucleation and disordered growth in chasing high-grade polycrystalline ***,single-crystal seeds crystallization(SCSC) method is proposed to obtain high-quality α-FAPbI perovskite films for the first *** single-crystals seeds(CsPbBr,CsPbI,FAPbBr,FAPb,MAPbBr,MAPbI) are employed to regulate α-FAPbI perovskite *** seeds act as nucleation sites and allow perovskite to grow *** rapid crystallization significantly improves the crystallinity of perovskite films with uniform morphology,large grain size,and less ***,FAPbBr seed prefers to grow α-FAPbI epitaxially from FAPbBr@PbI heterostructure through halogen anions exchange *** average grain size of FAPbBr-perovskite film is boosted to 2.6 μm,and the trap density reduced by 11 *** FAPbBr-PSCs achieve the maximum power conversion efficiency(PCE) of 23.84% with a high opencircuit voltage of 1.18 *** unencapsulated PSC enables to retain 91% of the initial PCE after 3000 hours of storage at 30～50% relative humidity and preserves 98.5% of the original value after 155 hours illumination with maximum power point tracking.

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基于AR模型和谱熵的自适应小波包络检测

中国机械工程 2017年第3期28卷 348-352页

作者：何翔高宏力郭亮吴远昊西南交通大学机械工程学院成都610031

针对传统故障诊断的包络问题,提出了一种基于自回归(auto regressive,AR)模型和谱熵的自适应复解析小波包络检测方法。通过AR模型从数据内在规律性上剔除机械振动信号中可线性预测的平稳成分,提取共振衰减的非平稳成分,在不同频带下进... 详细信息

针对传统故障诊断的包络问题,提出了一种基于自回归(auto regressive,AR)模型和谱熵的自适应复解析小波包络检测方法。通过AR模型从数据内在规律性上剔除机械振动信号中可线性预测的平稳成分,提取共振衰减的非平稳成分,在不同频带下进行复解析小波包络,结合谱熵在频域内与通带滤波的相关性选定最佳包络。仿真和试验数据分析结果表明,该方法能有效地提取故障特征频率,较传统方法自适应性更强,鲁棒性更高,包络效果更好,在工程应用中具有良好的前景。

关键词：自回归预测小波变换谱熵包络检测

大数据背景下基于特征学习的机械设备剩余寿命预测

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西南交通大学学报 2021年第4期56卷 730-735,768页

作者：郭亮李长根高宏力董勋向守兵西南交通大学机械工程学院四川成都610031

传统数据驱动剩余寿命的预测方法是通过信号处理从监测数据中手动提取特征并构建健康指标,而在大数据背景下,手动提取特征需要特定专家知识并耗费大量人力,为解决该问题,提出了一种基于特征学习的机械设备剩余寿命预测方法——自适应特... 详细信息

传统数据驱动剩余寿命的预测方法是通过信号处理从监测数据中手动提取特征并构建健康指标,而在大数据背景下,手动提取特征需要特定专家知识并耗费大量人力,为解决该问题,提出了一种基于特征学习的机械设备剩余寿命预测方法——自适应特征学习寿命预测方法(AFLRULP).该方法构建移动窗口数据矩阵解决单次采样中的数据波动问题,并建立了多层一维卷积神经网络将数据矩阵映射为机械设备的健康状态;根据失效阈值可以计算出机械设备的剩余寿命;采样轴承全寿命周期数据集合对提出的AFLRULP进行验证,并且与传统基于手动提取特征的方法进行寿命预测准确性的对比.研究结果表明:AFLRULP不需要人工提取特征,可从原始监测数据映射为机械设备的性能状态与剩余寿命,相对于现有的基于手动提取特征的寿命预测方法,提出的方法在轴承寿命预测累积相对准确率上平均提高了0.20.

关键词：工业大数据剩余寿命预测卷积神经网络轴承

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单通道全双工系统数字自干扰消除研究

半导体光电 2016年第3期37卷 404-407页

作者：马涛雷洪利向新空军工程大学航空航天工程学院西安710038

单通道全双工系统是一种在同时同频发送和接收信号的通信系统,因此本地接收机需要进行自干扰消除。文章对数字自干扰消除进行了研究,通过分析量化位数对误码率的影响得到ADC量化前的最大干信比;分析了解调后自干扰信号对期望信号的影响... 详细信息

单通道全双工系统是一种在同时同频发送和接收信号的通信系统,因此本地接收机需要进行自干扰消除。文章对数字自干扰消除进行了研究,通过分析量化位数对误码率的影响得到ADC量化前的最大干信比;分析了解调后自干扰信号对期望信号的影响,得到自干扰消除需要达到的消除量;最后给出了自干扰信道估计的模型,为数字自干扰消除的实现提供了理论依据。

关键词：单通道全双工数字自干扰消除模数转换信道估计频移键控

Transferable equivariant graph neural networks for the Hamiltonians of molecules and solids

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npj Computational Materials 2023年第1期9卷 446-458页

作者： Yang Zhong Hongyu Yu Mao Su Xingao Gong Hongjun xiang Key Laboratory of Computational Physical Sciences(Ministry of Education) Institute of Computational Physical SciencesState Key Laboratory of Surface Physicsand Department of PhysicsFudan UniversityShanghai 200433China Shanghai Qi Zhi Institute Shanghai 200030China

This work presents an E(3)equivariant graph neural network called HamGNN,which can fit the electronic Hamiltonian matrix of molecules and solids by a complete data-driven *** invariant models that achieve equivariance approximately through data augmentation,HamGNN employs E(3)equivariant convolutions to construct the Hamiltonian matrix,ensuring strict adherence to all equivariant constraints inherent in the physical *** contrast to previous models with limited transferability,HamGNN demonstrates exceptional accuracy on various datasets,including QM9 molecular datasets,carbon allotropes,silicon allotropes,SiO_(2) isomers,and BixSey *** trained HamGNN models exhibit accurate predictions of electronic structures for large crystals beyond the training set,including the Moirétwisted bilayer MoS2 and silicon supercells with dislocation defects,showcasing remarkable transferability and generalization *** HamGNN model,trained on small systems,can serve as an efficient alternative to density functional theory(DFT)for accurately computing the electronic structures of large systems.

关键词： Hamiltonian solids isomers

Apelin aggravates the migration and invasion of non-small cell lung cancer cells via YAP1

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Frigid Zone Medicine 2022年第1期2卷 53-64页

作者： Wenchao Ma Di Zhu Tong Yu Junwen Xue xiang Sun Guofang Zhang Yumeng Hou Jinrui Li Yingzhun Chen hongli Shan Haihai Liang State-Province Key Laboratories of Biomedicine-Pharmaceutics of China Key Laboratory of Cardiovascular ResearchMinistry of EducationDepartment of PharmacologyCollege of PharmacyHarbin Medical UniversityHarbin 150081China Northern Translational Medicine Research and Cooperation Center Heilongjiang Academy of Medical SciencesHarbin Medical UniversityHarbin 150081China Department of Pathology the 2nd Affiliated HospitalHarbin Medical UniversityHarbin 150081China Research Unit of Noninfectious Chronic Diseases in Frigid Zone(2019RU070) Chinese Academy of Medical SciencesHarbin 150081China

Background:Apelin,an endogenous ligand of G-protein coupled receptor(GPCR),is a secreted peptide involved in the development of various ***,the relationship between apelin and non-small cell lung cancer(NSCLC)is not quite *** study was designed to investigate the effect and mechanism of apelin on cell proliferation,migration and invasion of NSCLC ***:Twelve NSCLC specimens were collected for hematoxylin-eosin(HE)staining and immunohistochemistry *** proliferation was examined by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT)and cell migration and invasion were assessed using wound-healing and transwell *** subcellular location of yes associated protein 1(YAP1)in A549 cells was determined by *** mRNA and protein levels in NSCLC tissues and cell lines were measured by qRT-PCR and western blot,***:Apelin was upregulated in tumor tissues compared with the adjacent *** promoted proliferation,migration,and invasion of A549 and H460 cells,which was reversed by competitive apelin receptor(APJ)antagonist ***,apelin upregulated YAP1 expression,whereas silence of YAP1 by small interfering RNA(siRNA)attenuated apelin-induced cell proliferation,migration and invasion and suppressed epithelial-mesenchymal transition ***:Apelin promotes NSCLC cells proliferation,migration,and invasion by modulating YAP1 and might be a potential therapeutic target for NSCLC treatment.

关键词： non-small cell lung cancer apelin yes associated protein 1 epithelial-mesenchymal transition

2012年春末昆明大暴雨的中尺度对流系统特征分析

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气象 2018年第11期44卷 1391-1403页

作者：梁红丽王曼李湘云南省气象台昆明650034 云南省气象科学研究所昆明650034

利用常规气象观测资料、NCEP/NCAR逐6 h1°×1°再分析资料、FY-2E红外云图TBB资料、昆明C波段多普勒雷达探测资料,结合中尺度数值模式的模拟结果,分析了2012年5月24日晚昆明大暴雨期间中尺度对流系统演变特征及形成机理。结果表明,此... 详细信息

利用常规气象观测资料、NCEP/NCAR逐6 h1°×1°再分析资料、FY-2E红外云图TBB资料、昆明C波段多普勒雷达探测资料,结合中尺度数值模式的模拟结果,分析了2012年5月24日晚昆明大暴雨期间中尺度对流系统演变特征及形成机理。结果表明,此次大暴雨是在高低空系统最佳配置下产生的。降水峰值出现时,低层增暖湿,从地面到500 hPa呈显著的对流性不稳定层结,700～500 hPa垂直风切变达14 m·s^(-1)。纬向结构上,暴雨中心低层东风增强,300 hPa以下纬向风辐合,中心强度为-28×10^(-5)s^(-1),150hPa以下上升气流中心强度为21 m·s^(-1),近地面水汽通量辐合为-20×10^(-5) g·hPa^(-1)·s^(-1)·cm^(-2);经向上,暴雨中心500 hPa以下南风风速辐合,上升气流增强,强度与纬向一致,低层水汽通量辐合中心强度为-30×10^(-5)g·hPa^(-1)·s^(-1)·cm^(-2),强于纬向水汽通量辐合。此外大暴雨中地形对南风的强迫也是显著的,抬升速度在0.4～1.0m·s^(-1)。这次强降水分为初始、加强、回落和衰减四个阶段,昆明近地层浅薄冷空气加强时,引发其东侧对流单体移向昆明,强降水发生;然后南风出现脉动,局地湿层增厚和垂直风切变加大,促使对流单体两度增强并出现降水峰值;第三次峰值则是弱南风脉动及对流单体合并所造成,由于移入的单体较之原地发展的单体弱得多,原地单体作用的降水峰值也明显小于前面两次。对流降水回波属于暖云性质的热带低质心降水回波。

关键词：局地大暴雨 γ中尺度对流系统结构特征触发因子地形

论艺术类专业在高等体育院校办学中的地位和作用

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成都体育学院学报 2017年第3期43卷 1-7页

作者：刘青邬红丽邱建钢李翔成都体育学院四川成都610041

我国高等体育院校作为行业特色型院校,如何通过艺术类专业的植入,提升体育院校的品位、精神内涵,发挥其在学校"立德树人"和"全环境育人"中的作用,意义十分重大。研究认为,体育院校办好艺术类专业是促进创"双一流"建设,提升学校品牌与影... 详细信息

我国高等体育院校作为行业特色型院校,如何通过艺术类专业的植入,提升体育院校的品位、精神内涵,发挥其在学校"立德树人"和"全环境育人"中的作用,意义十分重大。研究认为,体育院校办好艺术类专业是促进创"双一流"建设,提升学校品牌与影响力的需要;是促进大学校园文化建设、落实"立德树人"根本任务,形成"全环境育人"的需要;是促进体育文化建设,增强体育运动的表现价值与艺术修养的需要;是促进艺术学母学科发展,丰富其学科体系、提升其内涵的需要。在新形势下,高等体育院校办好艺术类专业应当科学定位专业的建设目标、发展方向;应当以体育运动实践为主体平台,深入挖掘"体育艺术"学科内涵,为实现"体艺融合"提供支撑;应当创造更多的、无愧于学校发展的作品,成为校园文化建设的主力军;应当发挥艺术教育实践功能,优化和提升各学科专业教育质量,积极构建多样性学术生态。

关键词：体育院校艺术类专业体艺融合专业建设 “双一流”建设发展走向