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基于支撑矢量机的天体光谱自动分类方法 被引量:9
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作者 覃冬梅 胡占义 赵永恒 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2004年第4期507-511,共5页
天体光谱自动识别系统的主要目标是对天体进行分类和参数测量。文章提出一种新的基于支撑矢量机的非活动天体与活动天体的自动分类方法。在信噪比低的时候 ,由于红移值未知使得噪声与发射谱线难于辨别 ,因此不能单纯依靠寻找发射谱线来... 天体光谱自动识别系统的主要目标是对天体进行分类和参数测量。文章提出一种新的基于支撑矢量机的非活动天体与活动天体的自动分类方法。在信噪比低的时候 ,由于红移值未知使得噪声与发射谱线难于辨别 ,因此不能单纯依靠寻找发射谱线来确定是否为活动天体。据此 ,在低噪声情况下对非活动天体与活动天体的区分成为难点。本方法结合主分量分析法和支撑矢量机 ,能够对红移值未知的活动天体与非活动天体比较有效地进行自动光谱分类 ,对天文界的大型巡天计划中的海量观测数据自动处理有比较重要的应用价值。 展开更多
关键词 支撑矢量机 主分量分析 非活动天体 天体光谱自动识别系统
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一种基于主分量分析的恒星光谱快速分类法 被引量:30
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作者 覃冬梅 胡占义 赵永恒 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2003年第1期182-186,共5页
恒星光谱分类是天体光谱自动识别中的重要组成部分。本文主要介绍一种实用的基于主分量分析(PCA)法对恒星光谱进行快速自动的分类方法。该方法在恒星的主分量空间中对样本点进行投影 ,并利用最近邻分类器进行分类 ,获得与恒星MK分类标... 恒星光谱分类是天体光谱自动识别中的重要组成部分。本文主要介绍一种实用的基于主分量分析(PCA)法对恒星光谱进行快速自动的分类方法。该方法在恒星的主分量空间中对样本点进行投影 ,并利用最近邻分类器进行分类 ,获得与恒星MK分类标准的光谱型基本一致的结果。本文的主要工作有 :(1 )利用PCA方法构造恒星光谱的特征矩阵 ,建构恒星的主分量空间 ;(2 )对恒星光谱进行主分量投影 ,对投影点进行光谱型和光度级的分类器设计 ,利用最近邻法分类 ,最后得出恒星的分类树。该分类法速度快 ,分类准确率较高 ,对目前许多大型光谱巡天计划所获得的大量光谱数据的处理有着重要的意义。 展开更多
关键词 恒星 光谱分析 主分量分析 特征矩阵 最近邻法 天体识别 光谱识别
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Knowledge Graph Based Method for Tracing Quality of Aerospace Products
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作者 WANG Ning CAO Lijun +5 位作者 DING Siyi MENG Yan LIU Huan ZHENG Xiaohu HUANG Wenbin LIU Xiaojia 《Journal of Donghua University(English Edition)》 CAS 2024年第5期513-524,共12页
Nowadays,the internal structure of spacecraft has been increasingly complex.As its“lifeline”,cables require extensive manpower and resources for manual testing,and it is challenging to quickly and accurately locate ... Nowadays,the internal structure of spacecraft has been increasingly complex.As its“lifeline”,cables require extensive manpower and resources for manual testing,and it is challenging to quickly and accurately locate quality problems and find solutions.To address this problem,a knowledge graph based method is employed to extract multi-source heterogeneous cable knowledge entities.The method utilizes the bidirectional encoder representations from transformers(BERT)network to embed word vectors into the input text,then extracts the contextual features of the input sequence through the bidirectional long short-term memory(BiLSTM)network,and finally inputs them into the conditional random field(CRF)network to predict entity categories.Simultaneously,by using the entities extracted by this model as the data layer,a knowledge graph based method has been constructed.Compared to other traditional extraction methods,the entity extraction method used in this study demonstrates significant improvements in metrics such as precision,recall and an F1 score.Ultimately,employing cable test data from a particular aerospace precision machining company,the study has constructed the knowledge graph based method in the field to achieve visualized queries and the traceability and localization of quality problems. 展开更多
关键词 knowledge graph named entity recognition quality control aerospace product
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Roles of pattern recognition receptors in diabetic nephropathy 被引量:1
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作者 Zhi-feng ZHOU Lei JIANG +4 位作者 Qing ZHAO Yu WANG Jing ZHOU Qin-kai CHEN Jin-lei LV 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2020年第3期192-203,共12页
Diabetic nephropathy(DN)is currently the most common complication of diabetes.It is considered to be one of the leading causes of end-stage renal disease(ESRD)and affects many diabetic patients.The pathogenesis of DN ... Diabetic nephropathy(DN)is currently the most common complication of diabetes.It is considered to be one of the leading causes of end-stage renal disease(ESRD)and affects many diabetic patients.The pathogenesis of DN is extremely complex and has not yet been clarified;however,in recent years,increasing evidence has shown the important role of innate immunity in DN pathogenesis.Pattern recognition receptors(PRRs)are important components of the innate immune system and have a significant impact on the occurrence and development of DN.In this review,we classify PRRs into secretory,endocytic,and signal transduction PRRs according to the relationship between the PRRs and subcellular compartments.PRRs can recognize related pathogen-associated molecular patterns(PAMPs)and danger-associated molecular patterns(DAMPs),thus triggering a series of inflammatory responses,promoting renal fibrosis,and finally causing renal impairment.In this review,we describe the proposed role of each type of PRRs in the development and progression of DN. 展开更多
关键词 Diabetic nephropathy Innate immunity Pattern recognition receptor PATHOGENESIS
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