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The Optimization and Improvement of MapReduce in Web Data Mining

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Journal of Software Engineering and Applications 2015年第8期8卷 395-406页

作者： Jun Qu Chang-qing yin Shangwei Song Logistics Department Tongji University Shanghai China School of Software Engineering Tongji University Shanghai China College of Design and Innovation Tongji University Shanghai China

Extracting and mining social networks information from massive Web data is of both theoretical and practical significance. However, one of definite features of this task was a large scale data processing, which remained to be a great challenge that would be addressed. MapReduce is a kind of distributed programming model. Just through the implementation of map and reduce those two functions, the distributed tasks can work well. Nevertheless, this model does not directly support heterogeneous datasets processing, while heterogeneous datasets are common in Web. This article proposes a new framework which improves original MapReduce framework into a new one called Map-Reduce-Merge. It adds merge phase that can efficiently solve the problems of heterogeneous data processing. At the same time, some works of optimization and improvement are done based on the features of Web data.

关键词： Cloud Computing Web Data MapReduce Map-Reduce-Merge

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多重分形谱及其计算

北京航空航天大学学报 2000年第3期26卷 256-258页

作者：王祖林周荫清北京航空航天大学电子工程系

多重分形理论是进行信号奇异性处理的有用工具 ,由于只有少数集合的多重分形谱可以有解析表达式 ,多重分形谱的计算是其中重要而又较难处理的问题 .简要介绍了多重分形理论的一种形式体系 ,提出了一种采用动态链表来进行多重分形谱计算... 详细信息

多重分形理论是进行信号奇异性处理的有用工具 ,由于只有少数集合的多重分形谱可以有解析表达式 ,多重分形谱的计算是其中重要而又较难处理的问题 .简要介绍了多重分形理论的一种形式体系 ,提出了一种采用动态链表来进行多重分形谱计算的方法 ,大幅度地降低了对存储器容量的要求 .用所提出的方法对康托集进行了计算 ,计算结果与理论结果相符 ,表明了算法的有效性 .

关键词：信息处理谱分析奇异性多重分形多重分形谱

一种干扰环境下的机载SAR慢动目标检测方法

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宇航学报 2009年第4期30卷 1620-1625,1646页

作者：史洪印周荫清陈杰北京航空航天大学电子信息工程学院北京100191 燕山大学信息科学与工程学院秦皇岛066004

在电磁干扰的环境下,经典的合成孔径雷达(SAR)的成像和地面动目标检测算法的性能将会变差甚至失效,因此研究存在干扰时的高效可行的SAR动目标检测方法具有重要的实际意义。提出一种将自适应波束形成技术和杂波抑制干涉(CSI)技术相结合... 详细信息

在电磁干扰的环境下,经典的合成孔径雷达(SAR)的成像和地面动目标检测算法的性能将会变差甚至失效,因此研究存在干扰时的高效可行的SAR动目标检测方法具有重要的实际意义。提出一种将自适应波束形成技术和杂波抑制干涉(CSI)技术相结合的阵列天线动目标检测方法。该方法首先采用自适应波束形成技术消除干扰,然后用CSI方法抑制地杂波并实现运动目标的检测。同时,采用不等间距偏置相位中心天线(DPCA)技术,消除了盲速区。从SAR天线结构和空间几何模型入手,详细分析了干扰抑制原理、杂波抑制和动目标检测原理并给出了其实现框图。最后通过计算机仿真,验证了该方法的可行性。

关键词：合成孔径雷达自适应波束形成抗干扰杂波抑制干涉地面动目标检测

Piezoresponse Force Microscopy Imaging of Ferroelectric Domains in Bi(Zn_(1/2)Ti_(1/2))O_(3)−Pb(Mg_(1/3)Nb_(2/3))O_(3)−PbTiO_(3) Piezoelectric Ceramics

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Chinese Physics Letters 2011年第8期28卷 297-299页

作者： LIU Li-Ming ZENG Hua-Rong CAO Zhen-Zhu LENG Xue ZHAO Kun-Yu LI Guo-Rong yin qing-Rui Shanghai Institute of Ceramics Chinese Academy of SciencesShanghai 200050 Kunming Institute of Physics Kunming 650223 College of Chemical Engineering Inner Mongolia University of TechnologyHuhhot 010051

Bismuth zinc titanate dopied lead magnesium niobate-lead titanate[Bi(Zn_(1/2)Ti_(1/2))O_(3)−Pb(Mg_(1/3)Nb_(2/3))O_(3)−PbTiO_(3)(BZT-PMN-PT)]piezoelectric ceramics are synthesized by the conventional solid state reaction *** domain structures and the evolutionary behavior of BZT-PMN-PT ceramics under an external in-plane electric field are investigated by piezoresponse force microscopy(PFM).It is found that the BZT doping has a significant effect on the domain configurations and the domain kinetic behavior of the piezoelectric BZT-PMN-PT solid solution *** embedded in the macrodomains,induced by the BZT dopant in the solid solution ceramics,are clearly observed by PFM and their volume increases with increasing amounts of BZT *** microdomains of BZT-PMN-PT piezoelectric ceramics exhibit better domain dynamic behavior stability than macrodomains under an external in-plane electric field.

关键词： ceramics piezoelectric behavior

The Larix kaempferi genome reveals new insights into wood properties

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Journal of Integrative Plant Biology 2022年第7期64卷 1364-1373页

作者： Chao Sun Yun-Hui Xie Zhen Li Yan-Jing Liu Xiao-Mei Sun Jing-Jing Li Wei-Peng Quan qing-yin Zeng Yves Van de Peer Shou-Gong Zhang State Key Laboratory of Tree Genetics and Breeding Chinese Academy of ForestryBeijing 100091China Key Laboratory of Tree Breeding and Cultivation of the State Forestry and Grassland Administration Research Institute of ForestryChinese Academy of ForestryBeijing 100091China Department of Plant Biotechnology and Bioinformatics Ghent UniversityGent B‐9052Belgium VIB Center for Plant Systems Biology Ghent B‐9052Belgium Nextomics Biosciences Co. LtdWuhan 430073China Department of Biochemistry Genetics and MicrobiologyPretoriaSouth Africa

Here,through single-molecule real-time sequencing,we present a high-quality genome sequence of the Japanese larch(Larix kaempferi),a conifer species with great value for wood production and ecological *** assembled genome is 10.97 Gb in size,harboring 45,828 protein-coding *** the genome,66.8%consists of repeat sequences,of which long terminal repeat retrotransposons are dominant and make up 69.86%.We find that tandem duplications have been responsible for the expansion of genes involved in transcriptional regulation and stress responses,unveiling their crucial roles in adaptive *** transcriptome analysis reveals that lignin content in *** is mainly determined by the process of monolignol *** expression values of six genes(LkC OMT7,LkC OMT8,LkL AC23,LkL AC102,LkP RX148,and LkP RX166)have significantly positive correlations with lignin *** results indicated that the increased expression of these six genes might be responsible for the high lignin content of the larches’***,this study provides new genome resources for investigating the evolution and biological function of conifer trees,and also offers new insights into wood properties of larches.

关键词： evolution gene expression genome Larix kaempferi wood properties

同步轨道星机双基地三通道SAR地面运动目标指示算法

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电子与信息学报 2009年第8期31卷 1881-1885页

作者：史洪印周荫清陈杰北京航空航天大学电子信息工程学院北京100191 燕山大学信息科学与工程学院秦皇岛066004

基于分数阶傅里叶变换(FrFT)和多通道杂波抑制干涉技术,提出一种同步轨道星机双基地SAR地面慢速运动目标检测和参数估计方法。首先根据同步轨道星机双基地SAR的特点,给出该模式下杂波对消的DPCA条件;然后从系统空间几何模型和回波信号入... 详细信息

基于分数阶傅里叶变换(FrFT)和多通道杂波抑制干涉技术,提出一种同步轨道星机双基地SAR地面慢速运动目标检测和参数估计方法。首先根据同步轨道星机双基地SAR的特点,给出该模式下杂波对消的DPCA条件;然后从系统空间几何模型和回波信号入手,详细推导了动目标聚焦成像、杂波抑制、动目标检测和参数估计的原理,最后通过计算机仿真,验证了该文算法的有效性。

关键词：合成孔径雷达双基地地球同步轨道杂波抑制地面动目标检测分数阶傅里叶变换

4-Selena-7-thiaoctyl Polystyrene-supported Platinum Complex as Hydrosilylation Catalyst

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Chemical Research in Chinese Universities 1998年第4期14卷 56-59页

作者： MENG Ling zhi KE Ai qing and CHEN Yuan yin (Department Chemistry, Wuhan University, Wuhan, 430072)

ＩｎｔｒｏｄｕｃｔｉｏｎＳｅｌｅｎｏｅｔｈｅｒｐｌａｔｉｎｕｍｃｏｍｐｌｅｘｅｓａｓａｎｅｗｋｉｎｄｏｆｈｙｄｒｏｓｉｌｙｌａｔｉｏｎｃａｔａｌｙｓｔｈａｖｅｂｅｅｎｄｒａｗｎｍｕｃｈａｔｅｎｔｉｏｎｒｅｃｅｎｔｌｙ... 详细信息

ＩｎｔｒｏｄｕｃｔｉｏｎＳｅｌｅｎｏｅｔｈｅｒｐｌａｔｉｎｕｍｃｏｍｐｌｅｘｅｓａｓａｎｅｗｋｉｎｄｏｆｈｙｄｒｏｓｉｌｙｌａｔｉｏｎｃａｔａｌｙｓｔｈａｖｅｂｅｅｎｄｒａｗｎｍｕｃｈａｔｅｎｔｉｏｎｒｅｃｅｎｔｌｙ．Ａｓｅｒｉｅｓｏｆｓｅｌｅｎｏｅ...

关键词： Polystyrene bound catalyst platinum complex hydrosilylation β methylthioethyl β ′ hydroxyethyl selenoether

Olfactory ecto-mesenchymal stem cell-derived exosomes ameliorate murine Sjögren’s syndrome by modulating the function of myeloid-derived suppressor cells

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Cellular & Molecular Immunology 2021年第2期18卷 440-451页

作者： Ke Rui Yue Hong Qiugang Zhu Xiaofei Shi Fan Xiao Hailong Fu qing yin Yida Xing Xinfeng Wu Xiaodan Kong Huaxi Xu Jie Tian Shengjun Wang Liwei Lu Department of Laboratory Medicine Affiliated Hospital of Jiangsu UniversityZhenjiangChina Department of Immunology Jiangsu Key Laboratory of Laboratory MedicineSchool of MedicineJiangsu UniversityZhenjiangChina Department of Rheumatology The First Affiliated Hospital and College of Clinical MedicineHenan University of Science and TechnologyLuoyangChina Department of Pathology and Shenzhen Institute of Research and Innovation The University of Hong Kong Center for Clinical Laboratory The First Affiliated Hospital of Soochow UniversitySuzhouChina Department of Rheumatology The Second Affiliated Hospital of Dalian Medical UniversityLiaoningChina

Sjögren’s syndrome(SS)is a systemic autoimmune disease characterized by progressive inflammation and tissue damage in salivary glands and lacrimal *** previous studies showed that myeloid-derived suppressor cells(MDSCs)exhibited impaired immunosuppressive function during disease progression in patients with SS and mice with experimental Sjögren’s syndrome(ESS),but it remains unclear whether restoring the function of MDSCs can effectively ameliorate the development of *** this study,we found that murine olfactory ecto-mesenchymal stem cell-derived exosomes(OE-MSC-Exos)significantly enhanced the suppressive function of MDSCs by upregulating arginase expression and increasing ROS and NO ***,treatment with OE-MSC-Exos via intravenous injection markedly attenuated disease progression and restored MDSC function in ESS ***,OE-MSC-Exo-secreted IL-6 activated the Jak2/Stat3 pathway in *** addition,the abundant S100A4 in OE-MSC-Exos acted as a key factor in mediating the endogenous production of IL-6 by MDSCs via TLR4 signaling,indicating an autocrine pathway of MDSC functional modulation by *** together,our results demonstrated that OE-MSC-Exos possess therapeutic potential to attenuate ESS progression by enhancing the immunosuppressive function of MDSCs,possibly constituting a new strategy for the treatment of Sjögren’s syndrome and other autoimmune diseases.

关键词： mesenchymal stem cells exosomes MDSCs Sjögren’s syndrome autoimmune diseases

分布式小卫星SAR回波信号精确仿真方法研究

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宇航学报 2006年第5期27卷 909-914页

作者：文竹周荫清陈杰北京航空航天大学电子信息工程学院201教研室北京100083

针对分布式小卫星SAR回波信号仿真,建立了回波信号的数学模型,并基于空间坐标变换建立了分布式小卫星SAR回波信号仿真模型。通过计算机仿真,生成了一组Cartwheel构型的主星带伴随星群的分布式小卫星SAR回波信号,并通过成像及干涉处理,... 详细信息

针对分布式小卫星SAR回波信号仿真,建立了回波信号的数学模型,并基于空间坐标变换建立了分布式小卫星SAR回波信号仿真模型。通过计算机仿真,生成了一组Cartwheel构型的主星带伴随星群的分布式小卫星SAR回波信号,并通过成像及干涉处理,得到干涉相位图,验证了模型的有效性。仿真结果证明,本文提出的仿真模型能够精确的模拟分布式小卫星SAR回波信号,并能够灵活地注入各种误差,生成有效的回波仿真数据。

关键词：卫星合成孔径雷达仿真