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Hybrid-Traffic-Detour Based Load Balancing for Onboard Routing in LEO Satellite Networks

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china Communications 2018年第6期15卷 28-41页

作者： Peilong Liu Hongyu Chen Songjie Wei Limin Li Zhencai Zhu Shanghai institute of Microsystem and Information Technology Chinese Academy of SciencesShanghai 200050China university of Chinese Academy of sciences Beijing 100049China Innovative Academy for Microsatellites Chinese Academy of SciencesShanghai 201203China school of Computer science and Engineering Nanjing University of Science and TechnologyNanjing 210094China College of Physics and Electronic Information Engineering Wenzhou UniversityWenzhou 325035China

To deal with the dynamic and imbalanced traffic requirements in Low Earth Orbit satellite networks, several distributed load balancing routing schemes have been proposed. However, because of the lack of global view, these schemes may lead to cascading congestion in regions with high volume of traffic. To solve this problem, a Hybrid-Traffic-Detour based Load Balancing Routing(HLBR) scheme is proposed, where a Long-Distance Traffic Detour(LTD) method is devised and coordinates with distributed traffic detour method to perform self-adaptive load balancing. The forwarding path of LTD is acquired by the Circuitous Multipath Calculation(CMC) based on prior geographical information, and activated by the LTDShift-Trigger(LST) through real-time congestion perception. Simulation results show that the HLBR can mitigate cascading congestion and achieve efficient traffic distribution.

关键词： satellite networks load balancing cascading congestion traffic detour

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铝酸钠液体速凝剂性能及作用机理

沈阳建筑大学学报（自然科学版） 2009年第6期25卷 1125-1130页

作者：赵苏郭兴华夏义兵左明贺沈阳建筑大学材料科学与工程学院辽宁沈阳110168 北京市建筑工程研究院工程材料所北京100039

目的研究不同物质的量比铝酸钠液体速凝剂对水泥性能的影响规律,探讨其促凝机理及存在最佳掺量的原因.方法测试了不同物质的量比的铝酸钠液体速凝剂对水泥的凝结时间和强度,利用差热分析,X-射线衍射和扫面电镜手段分析其作用机理.结果... 详细信息

目的研究不同物质的量比铝酸钠液体速凝剂对水泥性能的影响规律,探讨其促凝机理及存在最佳掺量的原因.方法测试了不同物质的量比的铝酸钠液体速凝剂对水泥的凝结时间和强度,利用差热分析,X-射线衍射和扫面电镜手段分析其作用机理.结果物质的量比为1.2时,铝酸钠液体速凝剂放置1 d便产生大量的沉淀.增大物质的量比时,稳定性也增加.不同物质的量比的铝酸钠液体速凝剂均存在最佳掺量,其凝结时间和强度都符合JC477-2005标准.结论铝酸钠液体速凝剂并不是靠生成大量钙矾石相互搭接实现速凝,而是促进各水泥矿物的反应形成大量的凝胶,并有一定量的板状晶体氢氧化钙和柱状晶体钙矾石(AFt)分布在其中.当掺量过大时,形成大量的六方片状晶体水铝石和单硫型水化硫铝酸钙(AFm),C-S-H凝胶和柱状钙矾石相对较少,导致结构不密实,速凝效果减弱.

关键词：铝酸钠液体速凝剂作用机理最佳掺量

Crofer22 APU铁素体不锈钢的氧化行为研究

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钢铁 2011年第12期46卷 67-70页

作者：肖旭陈雯王立民杨钢刘正东昆明理工大学冶金与能源工程学院云南昆明650093 钢铁研究总院结构材料研究所北京100081

Crofer22APU铁素体不锈钢是固体燃料电池连接体的备选材料之一。通过增重法研究了Crofer22APU铁素体不锈钢在800℃空气中的抗高温氧化动力学,并结合X射线衍射(XRD)、扫描电镜(SEM)、能谱分析(EDS)等手段,对氧化膜的形貌和组成进行了分... 详细信息

Crofer22APU铁素体不锈钢是固体燃料电池连接体的备选材料之一。通过增重法研究了Crofer22APU铁素体不锈钢在800℃空气中的抗高温氧化动力学,并结合X射线衍射(XRD)、扫描电镜(SEM)、能谱分析(EDS)等手段,对氧化膜的形貌和组成进行了分析。结果发现,Crofer22APU铁素体不锈钢在800℃下0～100h的平均氧化速率为0.032g/(m2.h);100～450h的平均氧化速率为0.0091g/(m2.h);450～550h的平均氧化速率为5.0×10-4g/(m2.h)。氧化膜分为内外两层,内层主要是含SiO2的氧化物,外层主要是含Cr2O3的氧化物。

关键词：固体燃料电池连接体氧化膜抗氧化

High-efficiency targeted modification of plant genomes using TALENs strategy

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High-efficiency targeted modification of plant genomes using...

Cloning and expression pattern of a dehydrin-like BDNI gene from drought-tolerant Boea crassifolia Hemsl.

从植物科学到农业发展——2012全国植物生物学大会

作者： Qiwei Shan~1,Yanpeng Wang~1,Zhen Liang~1,Jun Li,Yi Zhang~1,Kang Zhang~1,Jinxing Liu~1, Kunling Chen~1,Yong Zhang~2,Caixia Gao~(1*) 1 institute of Genetics and Developmental Biology,Chinese Academy of sciences,beijing 100101, china. 2 school of Life science and Technology,university of Electronic science and Technology of china, Chengdu 610054,china.

Recent advances in high-efficiency methods for targeted genome modification have equipped plant biologists with another powerful genetic tool to facilitate understanding gene functions and expedite translational research to develop crop varieties with higher productivity,enhanced nutrition and lower input *** genome modifications often require targeted cleavage of specific chromosomal sequences,which generates double strand DNA breaks(DSBs) and activates endogenous DNA repair *** have recently developed platforms to design and generate highly specific and active TALE nucleases(TALENs),for recognizing and cleaving desired DNA *** reagents and delivery methods have been optimized to achieve highly efficient targeted mutagenesis in a number of plant species,including rice,Brachypodium,wheat and *** have assembled specific TALENs designed to modify more than 20 genes from rice, Brachypodium and wheat,*** 35.2%of the transgenic rice resistant callus lines, TALENs introduced targeted mutations were *** high efficiencies make it possible to recover genome modifications even without enrichment regimes,As the results, our technology opens the door to make targeted genome modification of plants a routine practice and promises to facilitate creation of new crop varieties to meet burgeoning agricultural ***,the potential impact of targeted genome engineering technology on regulatory decisions will also be presented.

关键词： TALENs targeted genome modification

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Chinese science Bulletin 2000年第22期45卷 2072-2077页

作者： ZHAO Huiwu, LIU Han, YU Haiyuan, HU Yuanlei, GAO Yin, LI Zhenyu & LIN ZhongpingNational Laboratory of Protein Engineering and Plant Genetic Engineering , Peking university, beijing 100871, china Botanical institute, Chinese Academy of sciences, beijing 100093, china Correspondence should be addressed to Lin Zhongping

A 500-bp cDNA fragment was amplified via RT-PCR from drought-induced total RNA of the drought-tolerant B. crassifolia Hemsl. using primers based on the sequence of published dehydrin conserved region. By using 5’ RACE, full-length coding region (1 148 bp) of BDN1 gene was produced. It is a new member of the dehydrin gene family. Southern analysis indicated that BDN1 is present in the 6. crassifolia genome as a single-copy gene. Northern analysis revealed that its expression is inducible by drought and cold stresses as well as ABA application.

关键词： drought-tolerant plant Boea crassifolia Hemsl. dehydrin 5’ RACE BDN1 gene.

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高阶交换子在Hardy空间上的连续性

数学学报（中文版） 2005年第1期48卷 191-200页

作者：丁勇陆善镇张璞北京师范大学数学系北京100875 浙江工程学院信息与计算科学系杭州310018

本文研究了由齐性分数次积分和BMO函数生成的高阶交换子在某些Hardy空间、弱Hardy空间和Herz型Hardy空间上的连续性.

关键词： Herz型Hardy空间高阶交换子连续性分数次积分 BMO函数弱Hardy空间生成

Pollen Morphology and its Systematic and Ecological Significance in Rheum(Polygonaceae)from china

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Pollen Morphology and its Systematic and Ecological Signific...

Privilege Flow Oriented Intrusion Detection Based on Hidden Semi-Markov Model

第六届全国系统与进化植物学青年学术研讨会

作者： Yang Mei-Hua Zhang Da-Ming Zheng Jun-Hua Liu Jian-Quan(Laboratory of Systematic and Evolutionary Botany, institute of Botany, the Chinese Academy of science, beijing 100093 school of Pharmaceutical sciences, Peking university, beijing 100083 Northwest Plateau institute of Biology, the Chinese Academy of sciences, Qinghai 810001)

Pollen morphology of 40 species of Rheum *** to eight sections,was investigated under LM and *** new exine pattems were found in the species:a)microechinate-foveolate b)rugulate,c)verrucate-perforte,andd)verrucate-rugulate *** addition,two pattems,the Rheum-type pollens with microechinate-perforate andfine-reticulate,as previously described,were also confirmed in the present *** on above study the evolutiontrends of pollen morphology in the taxa involved were discussed phylogenetically as *** microechinate-foveloate/perforate exine pattem exist commonly,the pattem is,therefore,regarded as the most primitive type,deriving from thebasic microechinate-foveolate/perforate pattem,and followed by the rugulate and verrucate-perforate ***

关键词：

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Privilege Flow Oriented Intrusion Detection Based on Hidden ...

The Background of Regional Lead Isotopic Compositions and Its Application in the Lower and Middle Reaches of the Yangtze River and Neighbouring Areas

The 1st Chinese Conference on Trusted Computing and Information Security

作者： ZHONG An-ming, JIA Chun-fu College of Information Technology and sciences. Nankai university. Tianjin 300071 .china State Key Laboratory of Information Security, institute of Software of Chinese Academy of science, beijing 100039,china

＜正＞ A privilege flow oriented intrusion detection method based on HSMM （ Hidden semi-Markov Model） is discussed. The privilege flow model and HSMM are incorporated in the implementation of an anomaly detection IDS （Intrusion Detection System）. Using the data set of DARPA 1998, our experiment results reveal good detection performance and acceptable computation cost.

关键词： intrusion detection privilege flow model HSMM

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Acta Geologica Sinica(English Edition) 1997年第2期71卷 158-170页

作者： Ma Zhendong and Shan Guangxiang Geochemistry institute, china university of Geosciences, Wuhan, Hubei Geochemistry institute China University of Geosciences Wuhan Hubei [?]Ma Zhendong Born in 1943 graduated from beijing College of Geology in 1966 obtained M.S. Degree in geochemistry from beijing Graduate school of Wuhan College of Geology in 1981. He is now professor at china university of Geosciences (Wuhan) and mainly engages in teaching and research work on geochemistry and isotopic geochemistry.

The paper systematically deals with the background of regional isotopic compo-sitions in the lower and middle reaches of the Yangtze River and neighbouring areas. It isshown that the lead isotopic compositions of different geological formations and units are con-trolled by the primary mantle heterogeneity, dynamic process of crust-mantle interchange,abundances of uraninm, thorium and lead of various layers of the earth and timing. Studies onthe background of regional isotopic compositions may offer significant information forgeochemical regionalization, tracing of sources of ore-forming materials, and regionalprognosis of ore deposits.

关键词： background of regional lead isotopic compositions tracing action lower and middle reaches of the Yangtze River and neighbouring areas