一种基于以太网的网络存储协议

存储区域网（SAN）采用光纤通道协议,提供了一种性能优越但价格昂贵的网络存储技术方案.随着千兆以太网技术的发展和不断成熟,研究基于以太网的低成本网络存储技术具有十分重要的实用价值.在基于以太网TCP/IP的网络存储协议中,iSCSI最有可能代替光纤通道协议工作,但它存在协议层次多、协议处理开销大、通信效率低的缺点.而HyperSCSI是一种直接建立在以太网协议基础上的网络存储协议,具有协议层次少、通信效率高的优点.文中首先介绍了该协议的实现机制和性能分析结果,然后在以PC机构建的网络存储系统中进行了测试,分析和测试结果表明该协议适合于建立中小规模的基于廉价以太网技术的网络存储系统.     

网络管理技术应用探讨

从网络管理功能和网络管理实现两方面介绍计算机网络管理技术。阐述了网络管理技术的功能划分 ,即网络故障管理、网络配置管理、网络性能管理、网络计费管理和网络安全管理 ;着重介绍网络管理的实现方法 ,即SNMP协议、RMON技术和WBM技术     

一种面向SON的自组织行为管理协议

基于链路状态路由协议OSPFv3,提出一种面向自组织网络SON(self-organizing networks)的自组织行为管理协议,支持节点诞生、节点感知周围环境、节点关系建立/删除、节点迁移、节点克隆、节点休眠、节点苏醒、节点唤醒和节点死亡等生物行为.利用Quagga软件路由器,并修改其中的OSPFv3模块,对上述协议进行了原型实现,在参照CERNET2拓扑构建的网络平台上通过视频会议和视频直播应用进行了性能评价,结果表明,该协议是可行和有效的.     

Ad Hoc网络的实现与性能分析

提出了一种基于Linux系统的Ad Hoc网络实现方法.在现有的Ad Hoc协议中,选择以DSR(Dynamic RoutingProtocol)协议为基础,使用多个便携计算机组成了基于Linux系统的Ad Hoc网络.然后,构建一个网络会议测试环境,并以数据传输为基准对该网络的性能进行测试,并分析所得到的结果,给出该...     

物联网技术在网络移动节点资源能耗监测中的应用

移动节点资源能耗有效监测能提高节点寿命,提出基于物联网技术的网络移动节点资源能耗监测方法.采用物联网的优化组网方法进行网络移动节点资源能耗采集,构建网络移动节点资源采集的ZigBee物联网分布结构模型,构建随机链路检测协议下的移动节点分布路由探测协议,采用模糊关联特征检测方法进行网络移动节点资源能耗信息融合处理,构建网络移动节点测试功耗的衡量标准,采用能耗分簇调度协议实现网络移动节点资源能耗监测及最优化能耗管理,提高网络移动节点资源调度和能耗配置能力,实现节点的能耗可靠性监测.仿真结果表明,采用该方法进行网络移动节点资源能耗监测的实时性较好,监测输出的可靠性较高,检测结果准确.     

不同网络环境下大数据系统的测试与分析

为了研究网络架构和通讯协议对大数据处理与应用系统效率的影响,在介绍与分析不同网络架构和通讯协议的基础上,使用以太网和Infiniband网络连接,安装TCP/IP,IPoIB和RDMA协议,构建了Hadoop,Tachyon和Spark原型系统,使用通用测试工具和例程等进行了测试.测试结果表明相比使用TCP/IP,使用IPoIB能提高Hadoop的I/O性能4.6~5.6倍,减少Tachyon数据处理的时间开销达2%~27%,减少了Spark 90%~95%的时间开销,同时Spark性能提高了46倍.此外使用RDMA相比IPoIB减少了3%~15%的系统开销.最终分析得出,高速网络架构和高效通讯协议能有效提高大数据处理系统的I/O性能、处理效率和适应能力.     

以太网交换机TRILL协议设计和工程实现

该论文讨论了TRILL协议在以太网交换机上的设计和实现方法.首先简要介绍了数据中心网络的发展和所涉及的技术,并提出了使用TRILL来构建数据中心二层网络.再介绍了TRILL中相关概念、工作原理和优势.提出了交换机上实现TRILL协议功能的模块模型、以及各个模块的实现.该论文的研究为实现数据中心交换机的TRILL功能提供了启发性的解决方案.     

下一代远程网络配置管理系统的研究与实现

在全面分析成熟的SNMP技术、NETCONF协议和TR-069协议之后,实现了一种全新的基于XML的网络配置管理系统.该系统主体架构是基于NETCONF协议,通过转换SNMP 管理信息结构、管理信息库方式来实现NETCONF数据建模,并实现了TR-069协议中定义的自动网络配置功能,使得网络配置管理更智能化,并具有更高的安全性和稳定性.     

一种面向SON的单播路由协议

提出了一种面向自组织网络SON(self-organizing networks)的单播路由协议,支持应用服务质量QoS(quality of service)需求和路由器生物行为.基于OSPFv3/BGP4+,设计了自治域内和自治域间路由协议,包括报文格式与功能、链路状态描述结构、邻居信息表、单播路由表和协议工作流程等.基于Quagga软件路由器实现了提出的协议,并且在网络实验平台基于Iperf工具对其进行了性能评测.结果表明,该协议是有效的,具有较好的性能.     

低轨卫星通信系统仿真模型设计

本文提出一种低轨卫星通信系统仿真模型的设计方案,并在OPNET网络仿真软件的环境中搭建了低轨卫星通信系统的仿真劂络,实现了低轨卫星通信网络中的移动性管理协议,为加入多种移动性管理协议算法,进行分析比较,考察各自的性能构建了坚实的基础.     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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