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基于DiffServ的自适应IP QoS管理框架研究

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系统仿真学报 2001年第3期13卷 394-399页

作者：汤庸杨学良区海翔李显济彭重嘉中国科学技术大学研究生院计算机系北京100039 广东工业大学计算机学院广州510090

IP QoS已成为IP网络的核心技术。目前实现IP QoS的机制主要包括有多种，例如子带宽管理、MPLS、IntServ、DiffServ等，可以结合起来实现更完善的IP QoS。目前，比较一致的看法是在网络边缘采用IntServ，在网络主干采用DiffServ。我们在... 详细信息

IP QoS已成为IP网络的核心技术。目前实现IP QoS的机制主要包括有多种，例如子带宽管理、MPLS、IntServ、DiffServ等，可以结合起来实现更完善的IP QoS。目前，比较一致的看法是在网络边缘采用IntServ，在网络主干采用DiffServ。我们在局域网自适应IP QoS基础上，进一步研究了基于DiffServ的IP QoS。本文给出一种DiffServ结合IntServ实现彻底的端到端的IP QoS网络框架，提出了DiffServ实现自适应IP QoS管理的框架与方案，讨论了内部路由节点自适应QoS控制策略。最后讨论基于网络仿真软件NS2.一个简单实验结果。

关键词： DiffServ IntServ 服务质量 IP网局域网 Internet

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滇西北高原湿地区土地利用变化特征

山地学报 2007年第3期25卷 265-273页

作者：张强马友鑫刘文俊李红梅中国科学院西双版纳热带植物园中国科学院西双版纳热带植物园云南昆明6502.3 中国科学院研究生院北京100039

湿地景观格局的动态变化与区域土地利用/覆盖格局的变化有着十分紧密的联系。以纳帕海、碧塔海和属都湖三块高原湿地所在的云南省香格里拉县建塘镇为例,在遥感和GIS技术的支持下,对该区域1974、1987和2.00三期Landsat TM(ETM)影像进行... 详细信息

湿地景观格局的动态变化与区域土地利用/覆盖格局的变化有着十分紧密的联系。以纳帕海、碧塔海和属都湖三块高原湿地所在的云南省香格里拉县建塘镇为例,在遥感和GIS技术的支持下,对该区域1974、1987和2.00三期Landsat TM(ETM)影像进行了解译,分析了2. a间的土地利用/覆盖变化规律,并结合景观格局动态分析的方法,借助FRAGSTATS软件定量分析了该区景观格局特征及其动态变化。结果表明:该区土地利用/覆盖状况变化显著,主要土地利用/覆盖类型有林地以82. hm2.a的速度在大面积减少,并主要转为灌木林地,使得后者在2. a间扩大高达17倍,变化幅度最大。建设用地和耕地的面积分别扩大了6倍和2.,而草地和雪地面积持续减少。相应地,该区景观格局定量分析显示,有林地的斑块密度增大而平均斑块面积减小迅速,呈破碎化趋势,灌木林地的斑块密度、平均斑块面积均增加,草地则与之相反均减小,耕地的斑块密度降低而平均斑块面积增加,在不断融合成大斑块,其余各景观单元斑块密度增大平均斑块面积减小,同时各斑块几何形状在1987年变化最剧烈,景观格局趋于复杂。

关键词：香格里拉高原湿地土地利用/土地覆盖景观格局

Iron speciation in cherts from the Laobao Formation,South china:Implications for anoxic and ferruginous deep-water conditions

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Science Bulletin 2010年第Z2期 3189-3196页

作者： CHANG HuaJin 1,2.3,CHU XueLei 3,FENG LianJun 3 &HUANG Jing 3 1School of Life and Geography Sciences,Qinghai Normal university,Xining 810008,china 2.Key Laboratory of Tibetan Plateau Environment and Resources,Ministry of Education,Xining 810008,china 3Institute of Geology and Geophysics,chinese academy of Sciences,beijing 10002.,china

Cherts in the Laobao Formation in the Silikou section,South china were deposited in terminal Ediacaran *** speciations of iron in cherts,such as pyrite Fe(FeP),HCl-extractable Fe(FeH),and total Fe(FeT),and their interrelationships,are proxies for distinguishing oxic,anoxic but ferruginous,and sulfidic conditions,which is an effective method for studying the terminal Ediacaran ocean *** chert samples from the Laobao Formation,pyrite concentrations are generally low(2. and 0.84 and most exceed 0.38,and most of FeT/Al ratios range from 0.55 to 5.87(averaging 1.1).Relatively high content of highly reactive Fe and low content of pyrite indicate a scarcity of H2. and Fe-enriched *** features suggested that the deposition setting of Laobao cherts was anoxic and *** Ediacaran deep-water in the South china Basin was most likely anoxic and ferruginous,which played a key role in the emergence and evolution of early multicellular life.

关键词： cherts iron species paleoenvironment Ediacaran South china

Transitions among Mariana-,Japan-,Cordillera-and Alaska-type are systems and their final juxtapositions leading to accretionary and collisional orogenesis

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Transitions among Mariana-,Japan-,Cordillera-and Alaska-type...

Effect of Perched Water Tables on Aluminosilicate Stability and Soil Genesis

中国科学院地质与地球物理研究所第十届(2.10年度)学术年会

作者： WENJIAO XIAO~(1*),CHUNMING HAN~1,CHAO YUAN~2.MIN SUN~3, GUOCHUN ZHAO~3 & YEHUA SHAN~2.1 State Key Laboratory of Lithospheric Evolution,Institute of Geology and Geophysics, chinese academy of Sciences,{2. 10002.,china 2.Guangzhou Institute of Geochemistry,chinese academy of Sciences,Guangzhou 510640,china 3 Department of Earth Sciences,The university of Hong Kong,Hong Kong,china

’Arc system’ is used here as a collective term for a variety of arcs that occur along continental margins or in oceanic plates;it includes associated units from adjacent *** major arc systems(Mariana-,Japan-,Cordillera-and Alaska-type)can be distinguished along the Circum-Pacific *** Japan-type arc systems in ancient orogens(*** Altaids) may have been largely regarded as microcontinents because they have so-called Precambrian basement. Often the Cordillera-type arc systems can be very complicated,and if they are rifted away from the host continent they become more difficult to *** these arc systems interact mutually and with continental marginal sequences,leading to complicated accretionary and colhsional *** alternation between Western Pacific archipelagos and the Eastern Pacific active margin is the stereotype of accretionary and colhsional *** importantly, these four main types of arc systems can be juxtaposed into a final orogenic collage, which is another main expression of accretionary *** some parts of accretionary and colhsional orogens can be terminated by attachment of a continent-size craton such as Tarim or even India,and even so the accretionary and colhsional processes may continue elsewhere along *** significance of the interactions among these arc systems and their final juxtaposition has not been fully appreciated in ancient *** Altaids together with the Circum-Pacific orogens offers a good opportunity to study such accretionary-collisional orogenesis.

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Pedosphere 2000年第3期10卷 247-256页

作者： ZHANG MIN , GONG ZITONG and A. D. KARATHANASIS College of Resources and Environment, Shandong Agricultural university, Tai’an 2.1018 (china) Institute of Soil Science, the {2. academy of Sciences, Nanjing 2.0008 (china) College of Agriculture, U asteur.ivic.ve

The mineral stability and solute activities of soil solution extracted from selected horizons of seven studied pedons of Alfisols in Kentucky, USA, and the relationship between distribution of iron-manganese concretions and the restrictive layers were investigated. The results showed that the genesis and development of these soils and mineral weathering trends were strongly influenced by the depth of bedrock and the presence of perched water tables at lithic (limestone) interfaces due to the dissolution and buffering effect of limestone bedrock. The extractable Mg/Ca ratio as depth function and soil depth above bedrock could be used as indices of weathering and degree of soil development. Maximum iron-manganese concretion accumulation was found to occur in the horizon overlying clay horizon (>40% clay) with a sharp increase in clay content (>10%), which suggested that zones of Fe-Mn concretion accumulation in soils of the Inner Bluegrass Region appeared to be a sensitive genetic indicator of argillic horizons with restrictive permeability.

关键词： iron-manganese concretion perched water table soil environment soil genesD

Involvement of dopamine D1-like receptor in activity-induced long-term potentiation of GABAergic synapses in adult mouse dentate gyrus

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Involvement of dopamine D1-like receptor in activity-induced...

Operational Risk Assessment:An ERM-POT Approach

中国神经科学学会第四次会员代表大会暨第七届全国学术会议

作者： Hui-Kun WANG~(1,2.,Jian-Xia XIA~3,Shu-Min DUAN~1 1 Institute of Neuroscience and Key Laboratory of Neurobiology,Shanghai Institutes for Biological Sciences,chinese academy of Sciences,Shanghai 2.0031,{2. 2.graduate School of the chinese academy of Sciences,Shanghai 2.0031,{2. 3 Department of physiology,Third Military Medical university,Chongqing 400038,{2.

＜正＞Activity-dependent long-term changes in synaptic efficacy are thought to be important in learning and memory *** studies have investigated plasticity of excitatory glutamatergic synapses,while studies on plasticity of inhibitory synapses are lag ***,using gramicidin-perforated patch recording on Dentate Gyrus（DG） granule cells of adult mouse hippocampus,we studied activity-induced long-term potentiation（LTP） of GABAergic synapses and the involvement of dopamine D1-like receptor in LTP *** GABAA and GABAB receptor mediated outwards currents exhibited LTP after theta burst stimulation（TBS）.Further observations showed that presynaptic release probability was increased,while reversal potential of chloride did not change after TBS *** D1-like receptor antagonist had an inhibitory effect on basal GABAA and GABAB receptor mediated responses,which may caused by decreased presynaptic GABA ***,D1-like receptor antagonist blocked TBS induced LTP of both GABAA and GABAB *** of the D1 -like receptor-dependent LTP of GABAergic transmission are still under *** study will provide some hints that inhibitory GABAergic synapses are also plastic in the adult brain,and this activity-induced long-term change dependent on some endogenous modulators,such as dopamine. This activity-dependent change of inhibition also gives us the insight how the external inputs are controlled and regulated in the first order of the hippocampal trisynaptic pathway.

关键词： GABAA GABAB LTP dopamine D1-like

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Operational Risk Assessment:An ERM-POT Approach

利用功能磁共振成像技术探讨针刺作用机制的研究现状

首届风险分析与危机反应国际学术研讨会

作者： LI Jianping~1 MENG Fanjun~2.GAO Lijun~3 ~1Institute of Policy & Management,chinese academy of Sciences,{2. 100080,P.R.china ~2.conomics school,Renmin university of china,{2. 100872.P.R.china ~3 Management School,Shandong university of Finance,Jinan 2.0014,P.R.china

＜正＞Extreme value theory （EVT） has been proposed to the finance field more recently as a useful toolkit for analyzing the nonstandard （more precisely abnormal） data *** on the characteristic of operational losses of chinese Commercial Banks, we presented an ERM-POT （Exponential Regression Model and the Peaks-Over-Threshold） method to measure the operational risk under the EVT framework As we know,it is important to choose the threshold in ***,selection of the threshold by Hill plot or mean excess function （MEF） may produce biased *** ERM-POT method can lead to bias-corrected estimators and techniques for optimal *** the ERM-POT,we select the optimal threshold,and then the value-at- risk （VaR） is obtained. The experiment results show the method is reasonable.

关键词： Operational risk EVT POT ERM VaR

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针刺研究 2009年第3期34卷 207-211页

作者：任秀君王保国北京中医药大学针灸学院北京100029 首都医科大学附属北京天坛医院麻醉科北京100050 北京三博脑科医院麻醉科北京100093

本文概述了近年来国内外利用功能磁共振成像(functional magnetic resonance imaging,fMRI)技术进行针刺作用机制研究的现状。主要包括以下5个方面:①关于经络的研究;②关于针灸作用影响因素的研究;③针刺治疗作用机制的研究;④核磁试... 详细信息

本文概述了近年来国内外利用功能磁共振成像(functional magnetic resonance imaging,fMRI)技术进行针刺作用机制研究的现状。主要包括以下5个方面:①关于经络的研究;②关于针灸作用影响因素的研究;③针刺治疗作用机制的研究;④核磁试验设计方法;⑤核磁试验数据分析方法。研究表明,fMRI技术是研究针刺作用机制的一个新方法。

关键词：功能磁共振成像针刺疗法针刺作用机制试验设计和分析

Modulation Instability in Non Kerr-like Optical Fibers near the Zero Dispersion Point

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chinese Journal of Lasers 2000年第1期 80-85页

作者： LIU Xiumin 1,2.ZHANG Xiaoguang LIN Ning 1,2.ZHANG Tao 1,2.YANG Bojun 1 ( 1 Department of Basic Science, 2.Department of Electronics Engineering, beijing university of Posts and Telecommunications, beijing 100876, china)

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1　Ｉｎｔｒｏｄｕｃｔｉｏｎ　　Ｍｏｄｕｌａｔｉｏｎｉｎｓｔａｂｉｌｉｔｙ（ＭＩ）ｉｎｓｉｌｉｃａｂａｓｅｄｇｌａｓｓｆｉｂｅｒ，ｆｉｒｓｔｐｒｏｐｏｓｅｄｂｙＨａｓｅｇａｗａ［1］，ｒｅｆｅｒｓｔｏａｐｒｏｃｅｓｓｉｎｗｈｉｃｈａｃｏｎｔｉｎｕｏｕｓ...

关键词： modulation instability non Kerr like optical fiber zero dispersion point fourth order dispersion self steepening