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Sign language synthesis of individuation based on data model

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通讯和计算机（中英文版） 2008年第11期5卷 32-36页

作者： JIANG Feng yao Hong-xun WANG xiao-yu School of Computer Science and Technology Harbin Institute of Technology Harbin 150001 China College of Computer Science and Technology Harbin University of Science and Technology Harbin 150080 China

Kindergartens Reopening in the Period of Regular Epidemic Prevention and Control, Benefitial or Harmful?

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Current Medical Science 2020年第5期40卷 817-821页

作者： Qiao-qiao DONG Li-ru QIU Li-ming cheng Sai-nan SHU Yu CHEN Yue ZHAO Yan HAO Huan SHI xiao-ping LUO Department of Pediatrics Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Department of Laboratory Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

In the period of regular epidemic prevention and control of coronavirus disease 2019(COVID-19)in our country,work resumption has been fully *** there are still new sporadic local cases and imported cases across the *** this situation,whether kindergartens reopening will increase the risk of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)spread still remains *** reviewed two pediatric patients with moderate COVID-19,collected the epidemiologic information and monitored the cycle threshold value of rectal specimen and the viral loads,and discussed the transmission of SARS-CoV-2 in pediatric patients and the virulence of feces in children with moderate COVID-19,in order to analyze the risk of kindergartens reopening.

关键词： COVID-19 SARS-CoV-2 transmission children viral load

表征超大规模集成电路互连纳米薄膜硬度特性的声表面波的频散特性

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物理学报 2007年第4期56卷 2428-2433页

作者：肖夏尤学一姚素英天津大学电子信息工程学院天津300072 天津大学环境科学与工程学院天津300072

利用声表面波(SAW)的频散特性来表征超大规模集成电路(ULSI)互连系统中低介电常数(k)薄膜的物性具有准确、快速、对材料无损伤等突出优点.研究了Si(100)衬底上淀积低k薄膜的分层结构中,SAW沿任意方向传播的色散关系.引入坐标变换后,单... 详细信息

利用声表面波(SAW)的频散特性来表征超大规模集成电路(ULSI)互连系统中低介电常数(k)薄膜的物性具有准确、快速、对材料无损伤等突出优点.研究了Si(100)衬底上淀积低k薄膜的分层结构中,SAW沿任意方向传播的色散关系.引入坐标变换后,单层薄膜特征矩阵从9阶降到6阶,双层薄膜特征矩阵从15阶降到10阶,大幅度提高了计算速度,有利于生产ULSI过程中的在线监测.

关键词：超大规模集成电路声表面波传输方向频散特性

Epoxidation of styrene catalyzed by manganese (Ⅲ) porphyrins supported on chloromethylated polystyrene resin bearing crown ether groups

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Chinese Journal of Chemistry 1996年第4期14卷 303-309页

作者： YOU, Jing-Song xiao, You-Fa YU, xiao-Qi cheng, Ai-Xia LAN, Zhong-WeiDepartment of Chemistry, Sichuan University, chengdu, Sichuan 610064, China

Metalloporphyrins and crown ether groups were simultaneously supported on chloromethylated polystyrene resin to produce a series of polymer-supported catalysts. The synthesis of these catalysts has been studied. The influence of pH, concentrations of NaOCl and phase transfer catalysts on the epoxidation of styrene catalyzed by these catalysts has also been investigated. The experimental results show that manganese(Ⅲ) porphyrin bound to chloromethylated polystyrene which bears crown ether groups is effective catalysts for the epoxidation of styrene by sodium hypochlorite. The introduction of crown ether groups increases the catalytic efficiency of supported metalloporphyrins. The kinetics of epoxidation catalyzed by supported manganese(Ⅲ) porphyrins obeys Michaelis-Menten equation-the characteristic of enzyme-driven reaction.

关键词： Epoxidation crown ether manganese(Ⅲ) porphyrin styrene

非平衡样本下基于生成对抗网络过抽样技术的公司债券违约风险预测研究

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系统工程理论与实践 2022年第10期42卷 2617-2634页

作者：姚潇李可余乐安中央财经大学商学院北京100081 西南财经大学统计学院统计研究中心成都611130 西南财经大学金融安全协同创新中心成都611130 四川大学商学院成都610064

本文基于我国在公开市场发行过信用类债券的违约数据,利用了基于Wasserstein距离的生成对抗网络模型和SMOTE抽样技术对违约样本进行过抽样以提高非平衡样本下违约风险模型的预测效果.为检验过抽样技术对分类模型的改进效果,实证分析对... 详细信息

本文基于我国在公开市场发行过信用类债券的违约数据,利用了基于Wasserstein距离的生成对抗网络模型和SMOTE抽样技术对违约样本进行过抽样以提高非平衡样本下违约风险模型的预测效果.为检验过抽样技术对分类模型的改进效果,实证分析对不同的重抽样样本类别比例下分类模型的预测结果进行比较.研究结果表明过抽样技术能够显著地分类模型的预测精度,而且预测效果随着样本类别比例达到平衡而不断提高.和经典的SMOTE抽样技术相比,基于Wasserstein距离的生成对抗网络过抽样技术不仅可以提高分类模型的AUC指标,同时还能显著地改进F1得分.研究结果表明通过生成对抗网络对少数类样本进行过抽样能够显著地提升机器学习算法对债券违约风险的预测效果,为研究非平衡样本下的债券违约风险预测提供一种新的解决思路.

关键词：债券违约风险生成对抗网络非平衡样本分类过抽样技术

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基于像素差分神经网络的断层识别方法

地球物理学报 2023年第4期66卷 1649-1663页

作者：马啸姚刚张峰吴迪中国石油大学(北京)油气资源与探测国家重点实验室北京102249 中国石油大学(北京)地球物理学院北京102249 中国石油大学(北京)非常规油气科学与技术研究院北京102249

断层识别是地震解释的一项重要任务.相对传统的基于人工或半人工的断层检测方法,基于深度学习的断层检测方法具有自动化程度高等特点,近年来已经吸引了业界广泛兴趣.目前,大多数利用深度学习的断层识别方法都是基于语义分割或图像分类,... 详细信息

断层识别是地震解释的一项重要任务.相对传统的基于人工或半人工的断层检测方法,基于深度学习的断层检测方法具有自动化程度高等特点,近年来已经吸引了业界广泛兴趣.目前,大多数利用深度学习的断层识别方法都是基于语义分割或图像分类,但基于语义分割或图像分类的方法预测出的断层噪声较多.而边缘检测网络可以通过学习断层在地震剖面中不连续的特征,从而提高网络的抗噪能力.为了利用边缘检测网络的抗噪优点并提升其性能,本文采用基于像素差分的卷积运算构建出像素差分网络模型(Pixel Difference Networks,Pidinet).相较于传统的边缘检测网络,Pidinet将传统的边缘检测算子与深度学习网络结合,有效地提升了边缘检测的效果.为了使Pidinet网络更好地预测断层,本文对原始Pidinet网络进行了优化,去掉了相对断层识别任务而言多余的分支结构和卷积层.相对于传统的卷积运算,基于像素差分的卷积运算可以让神经网络更好地学习断层信息.为了让网络充分学习数据中的断层特征,本文将真实地震样本与合成地震样本混合得到训练所用数据集.实验证明Pidinet在交并比(Intersection over Union,IoU)方面较Holistically Nested Edge Detection(HED)边缘检测网络提升了10%左右.为了测试网络的迁移能力,本文只使用少量的数据样本对网络进行微调,迁移的结果较分类网络在F1分数(F1 Score)、灵敏度(sensitivity)等指标均提升了10%以上.最后,本文使用公开的实际地震数据进行测试,实验结果显示Pidinet识别出的断层连续且清晰,从而证明了基于边缘检测的深度学习算法在断层识别问题中的有效性.

关键词：边缘检测像素差分迁移学习断层识别

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Danshao Huaxian capsule in treatment of decompensated cirrhosis resulting from chronic hepatitis B

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Hepatobiliary & Pancreatic Diseases International 2006年第1期5卷 48-51页

作者： Ming-Liang cheng, Tong Lu, Yu-Mei yao and xiao-Xia Geng Department of Infectious Diseases, Affiliated Hospital of Guiyang Medical College, Guiyang 550004, China and Department of Internal Medicine, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA Department of Infectious Diseases Affiliated Hospital of Guiyang Medical College Guiyang 550004 China. chengml@***

BACKGROUND: The prognosis of decompensated cirrhosis resulting from chronic hepatitis B is poor, and the benefits of treatment with interferon are ourweight serious sideeffects and the risk of fatal exacerbation of disease. Danshao Huaxian capsule rapidly reduces hepatitis B virus(HBV)-DNA in serum to undetectable levels. METHODS: A total of 35 patients with chronic hepatitis B and decompensated cirrhosis were treated with Danshao Huaxian 1.2g. po. tid daily. Before the treatment, HBVDNA in serum was positive in all patients. Ten patients had Child-Pugh class B and 25, class C hepatitis B. Seven patients underwent liver transplantation within 6 months of initial treatment. Of the 10 patients of class B, 5 died within 6 months, and the other 5 did not complete the treatment for some reasons; the 25 patients of class C were treated for at least 6 months (mean =19 months). RESULTS: In most of the 25 patients, liver function was improved slowly but markedly after 9 months of treatment, showing a decreased level of serum bilirubin from 67±13 to 30±4μmol/L (P<0.05, baseline vs.6 months), an increased level of serum albumin from 27±1 to 34±1 g/L(P<0.05) and a decreased level of Child-Pugh score from 10.3±0.4 to 7.5+0.5 (P<0.05). Three patients developed resistance to Danshao Huaxian because of a mutation in the YMDD motif, but liver function was not deteriorated. Inhibition of viral replication with Danshao Huaxian resulted in a significant improvement of liver function in patients with decompensated HBV cirrhosis, but the long-term results remain uncertain. CONCLUSION: Danshao Huaxian capsule is effective in inhibiting viral DNA replication in patients with decompensated cirrhosis and making clinical improvement.

关键词： Danshao Huaxian capsule decompensated cirrhosis chronic hepatitis B prognosis

Exploring HONO formation and its role in driving secondary pollutants formation during winter in the North China Plain

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Journal of Environmental Sciences 2023年第10期132卷 83-97页

作者： Shaobin Zhang Guo Li Nan Ma yao He Shaowen Zhu Xihao Pan Wenlin Dong Yanyan Zhang Qingwei Luo Jeannine Ditas Uwe Kuhn Yuxuan Zhang Bin Yuan Zelong Wang Peng cheng Juan Hong Jiangchuan Tao Wanyun Xu Ye Kuang Qiaoqiao Wang Yele Sun Guangsheng Zhou Yafang cheng Hang Su Institute for Environmental and Climate Research Jinan UniversityGuangzhou 511443China Guangdong-Hongkong-Macao Joint Laboratory of Collaborative Innovation for Environmental Quality Guangzhou 511443China Max Planck Institute for Chemistry Mainz 55128Germany School of Atmospheric Sciences Nanjing UniversityNanjing 210023China Institute of Mass Spectrometry and Atmospheric Environment Jinan UniversityGuangzhou 510632China State Key Laboratory of Severe Weather&Key Laboratory for Atmospheric Chemistry Institute of Atmospheric CompositionChinese Academy of Meteorological SciencesBeijing 100081China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Gucheng Experimental Station of Ecological and Agricultural Meteorology Chinese Academy of Meteorological SciencesBeijing 100081China

Daytime HONO photolysis is an important source of atmospheric hydroxyl radicals(OH).Knowledge of HONO formation chemistry under typical haze conditions,however,is still *** the Multiphase chemistry experiment in Fogs and Aerosols in the North China Plain in 2018,we investigated the wintertime HONO formation and its atmospheric implications at a rural site *** different episodes based on atmospheric aerosol loading levels were classified:clean periods(CPs),moderately polluted periods(MPPs)and severely polluted periods(SPPs).Correlation analysis revealed that HONO formation via *** conversion of NO_(2)was more efficient on aerosol surfaces than on ground,highlighting the important role of aerosols in promoting HONO *** HONO budget analysis indicated a large missing source(with an average production rate of 0.66±0.26,0.97±0.47 and 1.45±0.55 ppbV/hr for CPs,MPPs and SPPs,respectively),which strongly correlated with photo-enhanced reactions(NO_(2)heterogeneous reaction and particulate nitrate photolysis).Average OH formation derived from HONO photolysis reached up to(0.92±0.71),(1.75±1.26)and(1.82±1.47)ppbV/hr in CPs,MPPs and SPPs respectively,much higher than that from O3 photolysis(i.e.,(0.004±0.004),(0.006±0.007)and(0.0035±0.0034)ppbV/hr).Such high OH production rates could markedly regulate the atmospheric oxidation capacity and hence promote the formation of secondary aerosols and pollutants.

关键词： HONO North China Plain Budget analysis OH radicals

人民币升值对股票收益率影响研究——基于中国制造业的面板数据分析

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财经理论与实践 2010年第2期31卷 30-34页

作者：姚小义肖燕湖南大学金融学院湖南长沙410079

基于2005年7月21日～2008年12月17日中国制造业上市公司的面板周数据，利用Jorion（1990）改进模型采探讨在这段时间内人民币升值对中国制造业上市公司股票收益率的影响。研究发现：人民币对美元的升值对制造业整体股票收益率有显著的... 详细信息

基于2005年7月21日～2008年12月17日中国制造业上市公司的面板周数据，利用Jorion（1990）改进模型采探讨在这段时间内人民币升值对中国制造业上市公司股票收益率的影响。研究发现：人民币对美元的升值对制造业整体股票收益率有显著的负向抑制作用，并且存在滞后效应；而在制造业各细分行业的影响存在差异。

关键词：人民币升值股票收益率制造业面板数据模型