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International Journal of Minerals,Metallurgy and Materials 2017年第2期24卷 171-178页

作者： ji-hong dong Chong Gao Yao Lu jian Han Xiang-dong jiao Zhi-xiong Zhu Mechanical and Electrical Engineering Institute Beijing University of Chemical TechnologyBeijing 100089China China Friction Stir Welding Center Beijing Aeronautical Manufacturing Technology Research InstituteBeijing 100024China Chinalco Research Institute of Science and Technology Beijing 100082China School of Mechanical Materials and Mechatronic EngineeringUniversity of WollongongNew South Wales 2522Australia Research Centre of Joining Technology in Ocean Engineering Beijing Institute of Petrochemical TechnologyBeijing 102617China

Cold-rolled 2024-T3 sheet alloy was subjected to bobbin-tool friction stir welding （BTFSW）. The microstructural characteristics and mechanical properties of the nugget zone in the as-welded state were investigated. The results show that the equiaxed grain size of BTFSW 2024-T3 alloy decreases from 7.6 to 2.8 μm as the welding speed is increased from 80 to 120 mm/min; in addition, fine grains are generated in the nugget zone and the size distribution is non-uniform. All A12CuMg （S＇） precipitates dissolve into the A1 matrix, whereas Mn-rich phases confirmed as T phases （Al20CuEMn3, A16Mn, or AlaMn） remain unchanged. The optimized parameters for BTFSW are veri- fied as the rotation speed of 350 r/min and the travel speed of 100 mm/min. The variations in precipitation and dislocation play more impor- tant roles than grain size in the nugget zone with respect to influencing the mechanical properties during the BTFSW process. After the BTFSW process, the fracture mode of base material 2024-T3 alloy transforms from ductile rupture to ductile-brittle mixed fi＇acture.

关键词： aluminum alloys friction stir welding mechanical properties microstructure

Functional Analysis of MYB73 of Arabidopsis thaliana Against Bipolaris oryzae

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Agricultural Sciences in China 2011年第5期10卷 721-727页

作者： jiA jiao XING ji-hong dong jin-gao HAN jian-min LIU Jun-sheng Laboratory of Molecular Plant Pathology Agricultural University of Hebei Baoding 071001 P.R.China

Bipolaris oryzae is a severe rice disease,resulting in significant economic ***73 gene of Arabidopsis was isolated based on T-DNA insertion mutants whose lose-of-function mutant increased susceptibility to *** of staining for H2O2 revealed that infection of incompatible *** caused much more strong brown patches on the leaves of myb73 mutant than those on the leaves of wild *** of MYB73 gene was induced by *** increased expression was severely impaired in the myb73 *** of MYB73 was severely decreased in the npr1,jar1,eds5,and sid2 mutants,suggesting MYB73 gene participates in the jasmonate （JA） and salicylic acid （SA） signaling *** of MYB73 who encoded an R2R3 MYB transcription factor was increased by SA,JA,and ethylene （ET） *** cDNA full-length sequence of MYB73 was 960 bp and a protein with 320 amino acids was *** predicted molecular weight of MYB73 was 34.85 *** expression of MYB73 gene was induced within 24 h of the inoculation,however,the expression of PR1,PDF1.2 and NPR1 weren＇t *** *** successfully infected myb73 mutant plants,the expression of PR1,PDF1.2 and NPR1 were ***,our results suggested that MYB73 is involved in NPR1-mediated SA and JA signaling pathways.

关键词： Arabidopsis MYB73 RT-PCR Bipolaris oryzae

Quality assessment of friction-stir-welded aluminum alloy welds via three-dimensional force signals

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Advances in Manufacturing 2024年第1期12卷 61-75页

作者： ji-hong dong Yi-Ming Huang jia-Lei Zhu Wei Guan Xu-Kai Ren Huan-Wei Yu Lei Cui Beijing Institute of Petrochemical Technology Beijing102617People’s Republic of China Beijing Academy of Safety Engineering and Technology Beijing102617People’s Republic of China AVIC Manufacturing Technology Institute Beijing100024People’s Republic of China Tianjin Key Laboratory of Advanced Joining Technology School of Materials Science and EngineeringTianjin UniversityTianjin300350People’s Republic of China Shaoxing Special Equipment Testing Institute Shaoxing Key Laboratory of Special Equipment Intelligent Testing and EvaluationShaoxing312071ZhejiangPeople’s Republic of China

An online detection technology must be developed for realizing the real-time control of friction stir *** this study,the three-dimensional force exerted on a material during friction stir welding was collected synchronously and the relationship between the forces and welding quality was *** results indicated that the fluctuation period of the traverse force was equal to that of the lateral force during the stable welding *** phase difference between two horizontal forces wasπ/*** values of the horizontal forces increased with welding speed,whereas their amplitudes remained the *** proposed force model showed that the traverse and lateral forces conformed to an elliptical curve,and this result was consistent with the behavior of the measured *** variational mode decomposition was used to process the plunge *** intrinsic mode function that represented the real fluctuation in the plunge force varied at the same frequency as the spindle rotational *** tunnel defects occurred,the fluctuation period features were consistent with those obtained during normal welding,whereas the ratio parameter defined in this study increased significantly.

关键词： Friction stir welding(FSW) Three-dimensional force model Variational mode decomposition Tunnel defect

Clinical and electrophysiological profiles in early recognition of polyneuropathy, organomegaly, endocrinopathy, M-protein, and skin changes syndrome

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Chinese Medical Journal 2019年第14期132卷 1666-1672页

作者： Qin Wang Peng Liu Li-Li ji Shuai Wu Guo-dong Feng Xin Wang ji-hong dong Department of Neurology Zhongshan Hospital Fudan UniversityShanghai 200032China Department of Haematology Zhongshan Hospital Fudan UniversityShanghai 200032China

Background:The detection of polyneuropathy,organomegaly,endocrinopathy,M-protein,and skin changes (POEMS) syndrome at early stage is challenging for *** polyneuropathy could be the first manifestation,it could be misdiagnosed as chronic inflammatory demyelinating polyneuropathy (CIDP).The present study aimed to determine the clinical and electrophysiological features of POEMS syndrome to distinguish from ***:The data of a group of patients with POEMS (n =17) and patients with CIDP (n =17) in Zhongshan Hospital Fudan University from January 2015 to September 2017 were analyzed in this retrospective *** clinical features,neurological symptoms,and electrophysiological findings were compared between the two ***:Clinically,patients with POEMS demonstrated significantly more neuropathic pain in the lower extremities than patients with CIDP (58.8 % vs.11.8 %,P =0.01).Multisystem features like edema,skin change,organomegaly,and thrombocytosis were also pointed towards the diagnosis of POEMS ***,terminal latency index (TLI) was significantly higher in patients with POEMS than that in patients with CIDP (median nerve:0.39 [0.17-0.52] vs.0.30 (0.07-0.69),Z =-2.413,P =0.016;ulnar nerve:0.55 [0.23-0.78] vs.0.42 [0.12-0.70],Z =-2.034,P =0.042).Patients with POEMS demonstrated a higher frequency of absent compound muscle action potential of the tibial nerve (52.9% vs.17.6%,P =0.031),less conduction block (ulnar nerve:0 vs.35.3%,P =0.018),and less temporal dispersion (median nerve:17.6% vs.58.8%,P =0.032) than CIDP *** combination of positive serum monoclonal protein and high TLI (if either one or both were present) discriminated POEMS from CIDP with a sensitivity of 94.1% and 47.1% and specificity of 76.5% and 100.0%,***:POEMS syndrome could be distinguished from CIDP through typical clinical and electrophysiological characteristics in *** combination of serum monoclonal protei

关键词： Polyneuropathy Organomegaly Endocrinopathy M protein and skin changes syndrome Chronic inflammatory demyelinating polyradiculoneuropathy Terminal latency index

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融入事件知识的主题表示方法

计算机学报 2017年第4期40卷 791-804页

作者：孙锐郭晟姬东鸿武汉大学计算机学院武汉430072 乐山师范学院计算机科学学院四川乐山614000 武汉大学软件工程国家重点实验室武汉430072

主题模型已被广泛用于发现文档潜在主题.已有方法多采用词或短语来表示主题,然而这些方法生成的主题缺乏深层次的语义信息,可解释性比较差.文中提出使用结构化的事件来表示主题.一方面,事件包含比词或短语更丰富的语义;另一方面,一组相... 详细信息

主题模型已被广泛用于发现文档潜在主题.已有方法多采用词或短语来表示主题,然而这些方法生成的主题缺乏深层次的语义信息,可解释性比较差.文中提出使用结构化的事件来表示主题.一方面,事件包含比词或短语更丰富的语义;另一方面,一组相关的事件能更合理地解释并区分不同的主题.为解决事件作为基本单元所带来的稀疏性问题,该文在Biterm Topic Model(BTM)的基础上提出两种主题模型,采用两种不同的方式将事件的语义知识融入到主题生成过程中.其中,第1种模型利用Generalized Pólya Urn(GPU)模型天然的聚类效果加大语义相近的事件分配到同一主题的概率,而第2种模型则通过为每个biterm引入指示变量,合理地利用语义知识有效地解决同一个biterm中两个事件的主题分配问题.该文不仅从主题凝聚度和KL散度两个指标直接对主题模型进行评估,还通过将主题表示结果引入到文本分类任务中对模型进行了外部评估.实验结果表明文中提出的模型从共现和语义两个层面有效地解决了事件稀疏性问题.与基于词或短语的主题表示相比,事件结构所包含的语义信息提高了主题生成质量,使主题表示具有更强的可读性和主题判别性.

关键词：事件主题模型主题表示事件知识自然语言处理社交网络社会媒体

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基于图的半监督关系抽取

软件学报 2008年第11期19卷 2843-2852页

作者：陈锦秀姬东鸿厦门大学智能科学与技术系福建厦门361005 武汉大学计算机系湖北武汉430072

提出利用基于图的半监督学习算法,即标注传递算法,指导计算机从非结构化的文本中自动识别出实体之间的关系.该方法首先利用图策略来建立关系抽取的模型.在这个图模型中,各个有标签和未标签的样本被表示成图上的各个节点,而样本间的距离... 详细信息

提出利用基于图的半监督学习算法,即标注传递算法,指导计算机从非结构化的文本中自动识别出实体之间的关系.该方法首先利用图策略来建立关系抽取的模型.在这个图模型中,各个有标签和未标签的样本被表示成图上的各个节点,而样本间的距离则作为图上各边的权重.然后,关系抽取的任务就转化成在这个图上估计出一个满足全局一致性假设的标注函数通过对ACE(automatic content extraction)语料库的评测,结果显示,当只有少量的标签样本时,采用该标注传递的方法可以获得比基于SVM(support vector machine)的有监督关系抽取更好的性能,同时也明显优于基于Bootstrapping的半监督关系抽取的方法.

关键词：关系抽取基于图半监督学习标签传递

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基于基本要素的文摘内容连贯性评测模型

计算机学报 2008年第4期31卷 628-635页

作者：刘德喜姬东鸿江西财经大学信息管理学院武汉大学计算机学院武汉430079

文摘的自动化面临诸多因难,一个重要的原因是对文摘的内容缺乏有效的自动评测方法.文中提出了基于基本要素(BE)关系网格的文摘内容连贯性评测模型.模型以BE为内容单元,以BE中的"关系"为内容单元的语法角色,通过BE关系在BE关系网格中的... 详细信息

文摘的自动化面临诸多因难,一个重要的原因是对文摘的内容缺乏有效的自动评测方法.文中提出了基于基本要素(BE)关系网格的文摘内容连贯性评测模型.模型以BE为内容单元,以BE中的"关系"为内容单元的语法角色,通过BE关系在BE关系网格中的转移概率来表达文摘内容的连贯性.在DUC2005数据集上的评测结果显示,模型评测结果与人工评测结果的Pearson相关系数为0.408,比Lapata2005年提出的实体网格模型得到的结果提高了约66%.

关键词：自动文摘内容连贯性基本要素关系网格

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基于卷积网络的句子语义相似性模型

华南理工大学学报（自然科学版） 2017年第3期45卷 68-75页

作者：黄江平姬东鸿武汉大学计算机学院湖北武汉430072

句子间语义相似性的计算已成为自然语言处理领域的重要研究内容,如何有效地对句子建立语义模型已成为释义识别、文本相似性计算、问答和文本蕴涵等自然语言处理应用的基础任务.文中提出了一种并行的卷积神经网络模型,该模型的两个卷积... 详细信息

句子间语义相似性的计算已成为自然语言处理领域的重要研究内容,如何有效地对句子建立语义模型已成为释义识别、文本相似性计算、问答和文本蕴涵等自然语言处理应用的基础任务.文中提出了一种并行的卷积神经网络模型,该模型的两个卷积网络不仅对句子对中的单个句子建立句子向量表示,还对句子经卷积池化后的特征进行相似性度量,并获得句子间的相似性特征.采用释义识别及文本相似性两项任务进行模型性能的实验评测,结果显示,该模型能够较好地表示句子语义信息,其释义识别F1值相比基准实验提高了7.4个百分点,语义相似性评测的皮尔森相关系数比逻辑回归方法有7.1个百分点的提高.

关键词：卷积网络释义识别句子模型语义相似性

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面向产品评论分析的短文本情感主题模型

自动化学报 2016年第8期42卷 1227-1237页

作者：熊蜀峰姬东鸿武汉大学计算机学院武汉430072 平顶山学院平顶山467099

情感主题联合生成模型已经成功应用于网络评论分析.然而,随着智能终端设备的广泛应用,由于屏幕及输入限制,用户书写的评论越来越短,我们不得不面对短评论中的文本稀疏问题.本文提出了一个针对短文本的联合情感–主题模型SSTM(Short-text... 详细信息

情感主题联合生成模型已经成功应用于网络评论分析.然而,随着智能终端设备的广泛应用,由于屏幕及输入限制,用户书写的评论越来越短,我们不得不面对短评论中的文本稀疏问题.本文提出了一个针对短文本的联合情感–主题模型SSTM(Short-text sentiment-topic model)来解决稀疏性问题.不同于一般主题模型中通常采用的基于文档产生过程的建模方法,我们直接对整个语料集合的产生过程建模.在产生文档集的过程中,我们每次采样一个词对,同一个词对中的词有相同的情感极性和主题.我们将SSTM模型应用于两个真实网络评论数据集.在三个实验任务中,通过定性分析验证了主题发现的有效性,并与经典方法进行定量对比,SSTM模型的文档级情感分类性能也有较大提升.

关键词：情感分类情感主题模型主题模型短文本主题模型文本稀疏

Three Super Active Regions in the Descending Phase of Solar Cycle 23

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Chinese Journal of Astronomy and Astrophysics 2003年第6期3卷 491-494页

作者： hong-Qi Zhang, Xing-Ming Bao, Yin Zhang, ji-hong Liu, Shu-dong Bao, Yuan-Yong Deng, Wei Li, jie Chen, jin-Ping Dun, jiang-Tao Su, Juan Guo, Xiao-Fan Wang, Ke-Liang Hu, Gang-Hua Lin and dong-Guang WangNational Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 National Astronomical Observatories CAS NAOC Beijing 100012 China

We analyze the magnetic configurations of three super active regions, NOAA 10484, 10486 and 10488, observed by the Huairou Multi-Channel Solar Telescope (MCST) from 2003 October 18 to November 4. Many energetic phenomena, such as flares (including a X-28 flare) and coronal mass ejections (CMEs), occurred during this period. We think that strong shear and fast emergence of magnetic flux are the main causes of these events. The question is also of great interest why these dramatic eruptions occurred so close together in the descending phase of the solar cycle.

关键词： Sun: activity - Sun: flares - Sun: magnetic fields